Category Archives: Operative Neurosurgery

Update: Falcotentorial meningioma treatment

Falcotentorial meningioma treatment

The primary aim of surgical treatment for falcotentorial meningiomas is gross total excision. The vital surrounding brain structures make this a complex task.

Several surgical approaches have been described to treat falcotentorial meningiomas. These include infratentorial supracerebellar approachsuboccipital approachoccipital transtentorial approach, and combined supratentorial and infratentorial approaches 1) 2) 3).

There are two main issues in treating falcotentorial meningiomas. One is selecting the surgical approach, which includes design of the bone flap. The other main issue is whether main venous structures will be sacrificed for a radical tumor resection.

In all of the cases, Hong et al. tried to make an adequately sized bone flap, even when the tumor was quite large. Some authors have insisted on performing wide craniotomies for large falcotentorial meningiomas 4).

Quiñones-Hinojosa, et al. 5) described a bilateral occipital transtentorial/transfalcine approach for large falcotentorial meningiomas. They ligated and cut the transverse sinus after checking the patency of the occluded sinus, and used permanent aneurysmal clips to ligate the vein of Galenwhen the straight sinus was occluded. The area above and below the tentorium can provide wide exposure and reduce occipital lobe retraction during prolonged operation times. Moreover, this approach may allow surgeons some form of intraoperative flexibility in terms of their surgical plan.

Hong et al. do not suggest routine application of wide craniotomies, such as the combined supratentorial and infratentorial approach. This is because wide craniotomies may increase the total amount of bleeding, prolong the operation time, and increase the risk of cerebral cortex injury. Moreover, it is possible to completely remove huge falcotentorial meningiomas without neurological deficit via relatively small craniotomies.

A catheter for CSF drainage was inserted into the ventricle or cisternal space through the safest area in each patient. They also designed small craniotomies through which the possible access area covered the entire tumor territory. Thus, if a CSF drain is possible, then appropriately designed small craniotomies are sufficient to achieve complete tumor resection without cortex injury 6).

There are some reports that have described usage of ligation and sectioning of the transverse sinus with or without reanastomosis 7) 8).

Although many authors have reported safe ligation of the transverse-sigmoid sinus, some complications have been described 9) 10).

Every venous structure should be preserved even if they seem to lack significant function. This will help prevent complications associated with delayed lobar parenchymal hemorrhage that can be attributed to venous infarction.

In conclusion, surgical approaches should be tailored to each patient according to the origin and direction of tumor growth, feeding arteries, and the surrounding venous drainage system.

Hong et al. found that a relatively small craniotomy was sufficient to completely remove each tumor. Moreover, they found that the most important factors for avoiding surgical complications were to preserve vital deep neurovascular structures, as well as flow through the venous sinuses.

The results showed that falcotentorial meningiomas could be cured via single-stage operations without complications by applying careful perioperative planning and a delicate microsurgical technique 11).

Videos


In this operative video, the authors demonstrate an illustrative step-by-step technique for endoscopic-assisted microsurgical resection of a falcotentorial meningioma using the posterior interhemispheric retrocallosal transfalcine approach for a superiorly positioned falcotentorial meningioma. The surgical nuances are discussed, including the surgical anatomy, gravity-assisted interhemispheric approach in the lateral position, retrocallosal dissection, transfalcine exposure, tumor removal, and preservation of the vein of Galen complex. In summary, the posterior interhemispheric retrocallosal transfalcine approach is a useful surgical strategy for select superiorly positioned falcotentorial meningiomas.

Case series

2009

From 2001 to 2005, 9 patients underwent operation for meningiomas arising from the falcotentorial junction, with some extending to and/or invading the torcula. All patients were assessed preoperatively with magnetic resonance neuroimaging and cerebral angiography. Furthermore, preoperative embolization was attempted in all cases. A supratentorial/infratentorial torcular craniotomy technique was used in all but 1 of these cases.

The average dimensions of the falcotentorial meningiomas were 5.1 x 4.4 x 4.2 cm. The angiograms revealed that these tumors were fed by branches of the internal carotid artery, choroidal arteries, branches of the meningohypophyseal trunk, and branches of the posterior cerebral artery. Preoperative embolization was achieved in only 2 patients. Five patients had gross total resection (Simpson grade 1), and 4 had subtotal resection (Simpson grade 4). Two of the tumors (22%) recurred during a mean follow-up period of 49 months (range, 17-88 months). The most common complication after surgery was cortical blindness, but all postoperative visual deficits had fully recovered at the last follow-up evaluation within several months.

An excellent outcome can be expected with detailed preoperative neuroimaging and knowledge of the nuances of the surgical technique that we describe in detail in the article 12).

2006

Goto et al. evaluated their surgical experience over 20 years with 14 treated falcotentorial meningiomas.

In the past 20 years, 14 patients with falcotentorial junction meningiomas were surgically treated. There were seven men and seven women, whose ages ranged from 34 to 79 years. On the basis of neuroimaging studies, the authors analyzed the influence of the anatomical relationship of the tumor to the vein of Galen, patency of the vein of Galen, tumor size, and the signal intensities on the magnetic resonance images to determine possible difficulties that might be encountered during surgery and to prognosticate the outcome of surgery. Depending on the relationship with the vein of Galen, tumors were labeled as either a superior or an inferior type. All tumors were resected via an occipital transtentorial approach. The surgical outcome in eight patients was excellent; in the remaining six patients, it was fair. Of the prognostic factors, tumor location especially seemed to be the most important (p < 0.01, Fisher exact test). The outcome associated with the inferior type of tumor was significantly less optimal probably due to the relationship to the deep veins and the brainstem. In this series, the occlusion of deep veins did not significantly influence outcome.

Classification of the tumor location by preoperative neuroimaging studies can be helpful in estimating the surgical difficulty that might be encountered in treating the falcotentorial junction meningioma 13).

2003

Meningiomas arising from the falcotentorial junction are rare. As a result, their clinical presentation and surgical management are not well described. During the past 3 years, the authors have treated six patients with falcotentorial meningiomas.

Most patients presented with symptoms related to raised intracranial pressure, including headaches, papilledema, and visual and gait disturbances. Magnetic resonance imaging revealed a smooth, oval, or round mass, which was typically homogeneously enhancing. Angiography was useful in evaluating arterial supply for embolization, when possible, and determining the status of venous collateral supply and sinus patency. The authors detail the surgical technique used in all six patients. Postoperatively, patients experienced transient cortical blindness, which in all cases spontaneously resolved during the course of several days to weeks. They provide a comprehensive description of the presentation and surgical management of falcotentorial meningiomas.

An excellent outcome can be expected when surgery is predicated on detailed preoperative neuroimaging and knowledge of the nuances of the surgical technique 14).

2001

Okami et al. present four surgical cases. An occipital transtentorial approach was used in three cases, and a combined midline occipital and suboccipital approach in one case. Total tumour excision was impossible in two cases because of engulfing deep venous structures including the great vein of Galen. Postoperative Gamma knife radiosurgery was performed in these two cases. On the other hand, a posteriorly located tumour was relatively easy to remove, and macroscopic total removal was accomplished. In conclusion, precise microvascular anatomical knowledge is indispensable to satisfactorily excise meningiomas in the falcotentorial area without significant morbidity 15).

1995

Asari et al. describe the clinical features, neuroimaging studies, and results of surgical treatment of meningiomas of the falcotentorial junction and clarify the characteristics of this lesion based on a review of the literature and seven patients treated at their institution. The most common symptoms resulted from intracranial hypertension. Upward-gaze palsy appeared in only one patient. Computerized tomography (CT) showed no specific findings, but there was no evidence of edema around the tumor. Magnetic resonance (MR) imaging revealed a round, smooth-bordered mass with a peritumoral rim, without edema, and showing marked contrast enhancement. The multiplanar capability of MR imaging delineated the relationship between the tumor and adjacent structures better than did CT. Detailed knowledge of the vascular structures, especially evidence of occlusion of the galenic venous system and the development of collateral venous channels, is critical for successful surgery; stereoscopic cerebral angiography is necessary to achieve this aim. The seven patients described developed five types of collateral venous channels: through the basal vein of Rosenthal to the petrosal vein, through the veins on the medial surface of the parietal and occipital lobes to the superior sagittal sinus, through superficial anastomotic veins, through veins of the posterior fossa to the transverse or straight sinus, and through the falcian veins to the superior sagittal sinus. The first three types mainly developed after occlusion of the galenic system. The tumors were removed through the occipital transtentorial approach with a large window at the posterior part of the falx. A favorable prognosis for patients undergoing surgical treatment of falcotentorial junction meningiomas can be expected if detailed neuroimaging studies and microsurgical techniques are used 16).


The tumors were removed subtotally or totally via an occipital interhemispheric transtentorial approach and/or infratentorial supracerebellar approach. The postoperative courses were uneventful, and no neurological deficit was detected postoperatively. Pineal region tumors with a maximum diameter of 5 cm or larger should be operated on via a unilateral or bilateral occipital interhemispheric transtentorial approach, regardless of the angiographic findings, because this permits a wide operative field and can be followed, if necessary, by an infratentorial supracerebellar approach. Selection of the operative approach for a relatively small pineal region tumor should depend on the angiographic findings: downward displacement of the bilateral internal cerebral veins and the great vein of Galen indicates an occipital interhemispheric transtentorial approach, whereas upward displacement indicates an infratentorial supracerebellar approach 17).

Case reports

2017

One representative case of falcotentorial meningioma treated through an anterior interhemispheric transsplenial approach is also described. Among the interhemispheric approaches to the pineal region, the anterior interhemispheric transsplenial approach has several advantages. 1) There are few or no bridging veins at the level of the pericoronal suture. 2) The parietal and occipital lobes are not retracted, which reduces the chances of approach-related morbidity, especially in the dominant hemisphere. 3) The risk of damage to the deep venous structures is low because the tumor surface reached first is relatively vein free. 4) The internal cerebral veins can be manipulated and dissected away laterally through the anterior interhemispheric route but not via the posterior interhemispheric route. 5) Early control of medial posterior choroidal arteries is obtained. The anterior interhemispheric transsplenial approach provides a safe and effective surgical corridor for patients with supratentorial pineal region tumors that 1) extend superiorly, involve the splenium of the corpus callosum, and push the deep venous system in a posterosuperior or an anteroinferior direction; 2) are tentorial and displace the deep venous system inferiorly; or 3) originate from the splenium of the corpus callosum 18).

2006

Kawashima et al. reported, in anatomic studies, a occipital transtentorial approach: the occipital bi-transtentorial/falcine approach, to treat such lesions. Gusmão et al. present a patient with a large falcotentorial meningioma, located bilaterally in the posterior incisural space. The occipital bi-transtentorial/falcine approach allowed an excellent surgical exposure and complete tumor removal with an excellent patient outcome 19).

References

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Okami N, Kawamata T, Hori T, Takakura K. Surgical treatment of falcotentorial meningioma. J Clin Neurosci. 2001 May;8 Suppl 1:15-8. Review. PubMed PMID: 11386819.
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Raco A, Agrillo A, Ruggeri A, Gagliardi FM, Cantore G. Surgical options in the management of falcotentorial meningiomas: report of 13 cases. Surg Neurol. 2004 Feb;61(2):157-64; discussion 164. PubMed PMID: 14751629.
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Sekhar LN, Goel A. Combined supratentorial and infratentorial approach to large pineal-region meningioma. Surg Neurol. 1992 Mar;37(3):197-201. PubMed PMID: 1536024.
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Hong CK, Hong JB, Park H, Moon JH, Chang JH, Lee KS, Park SW. Surgical Treatment for Falcotentorial Meningiomas. Yonsei Med J. 2016 Jul;57(4):1022-8. doi: 10.3349/ymj.2016.57.4.1022. PubMed PMID: 27189300; PubMed Central PMCID: PMC4951445.
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Quiñones-Hinojosa A, Chang EF, Chaichana KL, McDermott MW. Surgical considerations in the management of falcotentorial meningiomas: advantages of the bilateral occipital transtentorial/transfalcine craniotomy for large tumors. Neurosurgery. 2009 May;64(5 Suppl 2):260-8; discussion 268. doi: 10.1227/01.NEU.0000344642.98597.A7. PubMed PMID: 19287325.
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Hwang SK, Gwak HS, Paek SH, Kim DG, Jung HW. Guidelines for the ligation of the sigmoid or transverse sinus during large petroclival meningioma surgery. Skull Base. 2004 Feb;14(1):21-8; discussion 29. PubMed PMID: 16145581; PubMed Central PMCID: PMC1151668.
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Al-Mefty O, Fox JL, Smith RR. Petrosal approach for petroclival meningiomas. Neurosurgery. 1988 Mar;22(3):510-7. PubMed PMID: 3362317.
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Goto T, Ohata K, Morino M, Takami T, Tsuyuguchi N, Nishio A, Hara M. Falcotentorial meningioma: surgical outcome in 14 patients. J Neurosurg. 2006 Jan;104(1):47-53. PubMed PMID: 16509146.
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Quinones-Hinojosa A, Chang EF, McDermott MW. Falcotentorial meningiomas: clinical, neuroimaging, and surgical features in six patients. Neurosurg Focus. 2003 Jun 15;14(6):e11. Review. PubMed PMID: 15669786.
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Asari S, Maeshiro T, Tomita S, Kawauchi M, Yabuno N, Kinugasa K, Ohmoto T. Meningiomas arising from the falcotentorial junction. Clinical features, neuroimaging studies, and surgical treatment. J Neurosurg. 1995 May;82(5):726-38. Review. PubMed PMID: 7714596.
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Matsuda Y, Inagawa T. Surgical removal of pineal region meningioma–three case reports. Neurol Med Chir (Tokyo). 1995 Aug;35(8):594-7. PubMed PMID: 7566392.
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Yağmurlu K, Zaidi HA, Kalani MY, Rhoton AL Jr, Preul MC, Spetzler RF. Anterior interhemispheric transsplenial approach to pineal region tumors: anatomical study and illustrative case. J Neurosurg. 2017 Jan 13:1-11. doi: 10.3171/2016.9.JNS16279. [Epub ahead of print] PubMed PMID: 28084911.
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Gusmão S, Oliveira MM, Arantes A, Ulhoa TH, Morato EG. Occipital bi-transtentorial/falcine approach for falcotentorial meningioma: case report. Arq Neuropsiquiatr. 2006 Mar;64(1):136-8. Epub 2006 Apr 5. PubMed PMID: 16622571.

Update: Robotic neurosurgery

Robotic neurosurgery

Advances in robotic medicine have been adopted by various surgical subspecialties as the benefits of this technology become more readily apparent: precision in narrow operative windows, tremor controlled movements, and modestly improved outcomes, among others.

The use of robotics in neurosurgery and, particularly, in stereotactic neurosurgery, is becoming more and more adopted because of the great advantages that it offers.

Robotic manipulators easily allow to achieve great precision, reliability, and rapidity in the positioning of surgical instruments or devices in the brain. The aim of a work was to experimentally verify a fully automatic “no hands” surgical procedure. The integration of neuroimaging to data for planning the surgery, followed by application of new specific surgical tools, permitted the realization of a fully automated robotic implantation of leads in brain targets. An anthropomorphic commercial manipulator was utilized. In a preliminary phase, a software to plan surgery was developed, and the surgical tools were tested first during a simulation and then on a skull mock-up. In such a way, several tools were developed and tested, and the basis for an innovative surgical procedure arose. The final experimentation was carried out on anesthetized “large white” pigs. The determination of stereotactic parameters for the correct planning to reach the intended target was performed with the same technique currently employed in human stereotactic neurosurgery, and the robotic system revealed to be reliable and precise in reaching the target. The results of this work strengthen the possibility that a neurosurgeon may be substituted by a machine, and may represent the beginning of a new approach in the current clinical practice. Moreover, this possibility may have a great impact not only on stereotactic functional procedures but also on the entire domain of neurosurgery 1).


In the case of surgery of the skull base, it has just emerged from an experimental phase.

Neurosurgery is one of the first organ systems in which robotic surgery can play a role, due to the high precision that is required to localize and manipulate within the brain, and the relatively fixed landmarks of the cranial anatomy.

Robotic technology has been incorporated into stereotactic and endoscopic procedures 2) 3).

Interest in robotic endoscopic surgery is high because of the small size of the incisions, cosmetic advantages, less invasive surgical techniques, decreased scar tissue, shorter duration of hospitalization and increased cost-effectiveness 4).

Other key neurosurgical applications for robots include robotised microscope 5) , telepresence 6) , and tumor resection 7).

see Stereotactic robot

see Robotic forceps

see Robot assisted angiography


Vascular neurosurgery, in particular, remains open to newer and more cutting edge treatment options for complex pathologies, and robotics may be on the horizon for such advances.

Menaker et al. from the Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA. seeked to provide a broad overview of these innovations in vascular neurosurgery for both practitioners well acquainted with robotics and those seeking to become more familiar. Technologies under development for cerebrovascular and endovascular neurosurgery include robot assisted angiography, guided operative microscopes, coil insertion systems, and endoscopic clipping devices. Additionally, robotic systems in the fields of interventional cardiology and radiology have potential applications to endovascular neurosurgery but require proper modifications to navigate complex intracerebral vasculature. Robotic technology is not without drawbacks, as broad implementation may lead to increased cost, training time, and potential delays in emergency situations. Further cultivation of current multidisciplinary technologies and investment into newer systems is necessary before robotics can make a sizable impact in clinical practice 8).

1)

Mazzone P, Arena P, Cantelli L, Spampinato G, Sposato S, Cozzolino S, Demarinis P, Muscato G. Experimental new automatic tools for robotic stereotactic neurosurgery: towards “no hands” procedure of leads implantation into a brain target. J Neural Transm (Vienna). 2016 May 19. [Epub ahead of print] PubMed PMID: 27194228.
2)

Louw DF, Fielding T, McBeth PB, Gregoris D, Newhook P, Sutherland GR. Surgical robotics: A review and neurosurgical prototype development. Neurosurgery. 2004;54(3):525–537.
3)

Mc Beth PB, Louw DF, Rizun PR, Sutherland GR. Robotics in neurosurgery. Am J Surg. 2004;188(4):68–75.
4)

Ichihara S, Bodin F, Pedersen JC, Porto de Melo P, Garcia JC Jr, Facca S, Liverneaux PA. Robotically assisted harvest of the latissimus dorsi muscle: A cadaver feasibility study and clinical test case. Hand Surg Rehabil. 2016 Apr;35(2):81-4. doi: 10.1016/j.hansur.2016.01.002. Epub 2016 Feb 18. PubMed PMID: 27117120.
5)

Giorgi C, Eisenberg H, Costi G, Gallo E, Garibotto G, Casolina DS. Robot-assisted microscope for neurosurgery. J Image Guid Surg. 1995;1(3):158–163.
6)

Hongo K, Goto T, Kakizawa Y, Koyama J, Kawai T, Kan K, et al. Micromanipulator system (NeuRobot): Clinical application in neurosurgery. Int Congr Ser. 2003;1256:509–513.
7)

Benabid AL, Lavallee S, Hoffmann D, Cinquin P, Demongeot J, Danel F. Potential use of robots in endoscopic neurosurgery. Acta Neurochir Suppl (Wien) 1992;54:93–97.
8)

Menaker SA, Shah SS, Snelling BM, Sur S, Starke RM, Peterson EC. Current applications and future perspectives of robotics in cerebrovascular and endovascular neurosurgery. J Neurointerv Surg. 2017 Aug 18. pii: neurintsurg-2017-013284. doi: 10.1136/neurintsurg-2017-013284. [Epub ahead of print] Review. PubMed PMID: 28821626.

Update: Cervical arthroplasty

Cervical arthroplasty was developed with the goal of preserving mobility of the cervical segment in patients with cervical degenerative disc disease.

Cervical total disc replacement (TDR) has been shown in a number of prospective clinical studies to be a viable treatment alternative to anterior cervical discectomy and fusion (ACDF) for symptomatic cervical degenerative disc disease. In addition to preserving motion, evidence suggests that cervical TDR may result in a lower incidence of subsequent surgical intervention than treatment with fusion.

One reason for this trend is the observation that in clinical studies, patients with a history of cervical arthrodesis seem to have a higher incidence of adjacent segment degeneration 1) 2) 3).

Furthermore, in biomechanical investigations, most authors have reported an increase in the segmental range of motion (ROM) and the intradiscal pressure (IDP) in the levels proximal and distal to a simulated mono- or bisegmental arthrodesis 4) 5) 6) 7) 8) 9) 10) 11) 12) 13).

While anterior cervical discectomy and fusion (ACDF) has been the standard of care for 2-level disease, a randomized clinical trial (RCT) suggested similar outcomes.

There are also critical debates regarding the long-term effects of heterotopic ossification (HO) and the prevalence of adjacent-level degeneration.

Evidence

Several large-scale clinical trials demonstrate the efficacy of 1- and 2-level cervical disc arthroplasty (CDA) for degenerative disc disease (DDD) in the subaxial cervical spine, while other studies reveal that during physiological neck flexion, the C4-5 and C5-6 discs account for more motion than the C3-4 level, causing more degenerative disc disease (DDD).

The results of a observational study were in accordance with those of the published randomized controlled trials (RCTs), suggesting substantial pain reduction both after anterior cervical interbody fusion (AIF) and Cervical total disc replacement, with slightly greater benefit after arthroplasty. The analysis of atypical patients suggested that, in patients outside the spectrum of clinical trials, both surgical interventions appeared to work to a similar extent to that shown for the cohort in the matched study. Also, in the longer-term perspective, both therapies resulted in similar benefits to the patients 14).

The available evidence showed that most of the pre-selected factors had no effect on outcome after CTDR, and the range of motion (ROM) success rate, incidence of heterotopic ossification (HO) and radiographic adjacent segment degeneration (r-ASD)/adjacent segment disease (ASD), and surgery rate for ASD are acceptable. There is a lack of evidence for some factors 15).

With a significant exception of a Cochrane review, the methodological quality of systematic reviews evaluating the evidence of C-ADR versus ACDF has to be improved. 16).

Outcome

Cervical total disc replacement presented favorable functional outcomes, fewer adverse events, and fewer secondary surgical procedures. The efficacy and safety of cervical total disc replacement are superior to those of fusion. Longer-term, multicenter studies are required for a better evaluation of the long-term efficacy and safety of the two procedures.

Although cervical disc arthroplasty (CDA) at C3-4 was infrequent, the improved clinical outcomes of CDA were similar at C3-4 to that in the other subaxial levels of the cervical spine at the approximately 5-year follow-ups. In this Asian population, who had a propensity to have ossification of the posterior longitudinal ligament, there was more heterotopic ossification (HO) formation in patients who received CDA at the C3-4 level than in other subaxial levels of the cervical spine. While the type of artificial discs could have confounded the issue, future studies with more patients are required to corroborate the phenomenon 17).

Cost-effectiveness

A study is the first to report the comparative cost-effectiveness of cervical total disc replacement (cTDR) vs anterior cervical discectomy and fusion(ACDF) for 2-level degenerative disc disease at 5 years. Ament et al conclude that, because of the negative incremental cost-effective ratio (ICER), cTDR is the dominant modality 18)

Patients who underwent CTDR for single-level degenerative disease had lower readmission rates, lower reoperation rates, and reduced index and total costs than those treated with ACDF. Cervical disc arthroplasty (CDA) was effective in reducing the monthly cost of care compared with ACDF19).

Based on a modeling evaluation, CTDR was found to be more effective and less costly over a 7-year time horizon for patients with single-level symptomatic degenerative disc disease. These results are robust across a range of scenarios and perspectives and are intended to support value-based decision making 20).

The incremental cost-effectiveness ratio of CTDR compared with traditional ACDF is lower than the commonly accepted threshold of $50,000 per QALY. This remains true with varying input parameters in a robust sensitivity analysis, reaffirming the stability of the model and the sustainability of this intervention 21).

At the same time, while generating clinical results comparable to spinal fusion, TDR incurred significantly lower costs. Therefore, both from the medical and from the financial point of view, TDR is a viable choice in the treatment of DDP 22).

Results of the sensitivity analysis indicated that CDR must remain functional for at least 14 years to establish greater cost-effectiveness than ACDF. Since the current literature has yet to demonstrate with certainty the actual durability and long-term functionality of CDR, future long-term studies are required to validate the present analysis 23).


Although cervical total disc replacement (TDR) has shown equivalence or superiority to anterior cervical discectomy and fusion (ACDF), potential problems include nonphysiological motion (hypermobility), accelerated degeneration of the facet joints, particulate wear, and compromise of the mechanical integrity of the endplate during device fixation.

There is no definitive evidence that TDR has better intermediate-term results than anterior cervical discectomy and fusion (ACDF) 24).


3D motion analysis data comparing patients after ACDF and AD replacement in ten patients who underwent C5-6 ACDF and 7 who underwent C5-6 AD replacement were enrolled. Using biplanar fluoroscopy and a model-based track technique (accurate up to 0.6 mm and 0.6°), motion analysis of axial rotation and flexion-extension of the neck was performed. Three nonoperative segments (C3-4, C4-5, and C6-7) were assessed for both intervertebral rotation (coronal, sagittal, and axial planes) and facet shear (anteroposterior and mediolateral). Results There was no difference in total neck motion comparing ACDF and AD replacement for neck extension (43.3° ± 10.2° vs 44.3° ± 12.6°, p = 0.866) and rotation (36.0° ± 6.5° vs 38.2° ± 9.3°, p = 0.576). For extension, when measured as a percentage of total neck motion, there was a greater amount of rotation at the nonoperated segments in the ACDF group than in the AD group (p = 0.003). When comparing specific motion segments, greater normalized rotation was seen in the ACDF group at C3-4 (33.2% ± 4.9% vs 26.8% ± 6.6%, p = 0.036) and C6-7 (28.5% ± 6.7% vs 20.5% ± 5.5%, p = 0.009) but not at C4-5 (33.5% ± 6.4% vs 31.8% ± 4.0%, p = 0.562). For neck rotation, greater rotation was observed at the nonoperative segments in the ACDF group than in the AD group (p = 0.024), but the differences between individual segments did not reach significance (p ≥ 0.146). Increased mediolateral facet shear was seen on neck extension with ACDF versus AD replacement (p = 0.008). Comparing each segment, C3-4 (0.9 ± 0.5 mm vs 0.4 ± 0.1 mm, p = 0.039) and C4-5 (1.0 ± 0.4 mm vs 0.5 ± 0.2 mm, p = 0.022) showed increased shear while C6-7 (1.0 ± 0.4 mm vs 1.0 ± 0.5 mm, p = 0.767) did not.

This study illustrates increased motion at nonoperative segments in patients who have undergone ACDF compared with those who have undergone AD replacement. Further studies will be required to examine whether these changes contribute to adjacent-segment disease 25).

The data from a investigational device exemption (IDE) study through 48 months signify a number of clinically relevant benefits for total disc replacement (TDR) over anterior cervical discectomy and fusion (ACDF). Patients experienced improved clinical outcomes with TDR—including improvement in pain and function outcomes and superiority in overall primary endpoint success. Additionally, incidences of adjacent segment degeneration and subsequent surgeries were reduced with TDR. Perhaps future studies and also longer-term followup of this patient cohort may continue to establish 2-level cervical TDR as a superior surgical option for symptomatic degenerative disc disease 26).


Cervical artificial disc replacement (ADR) is indicated for the treatment of severe radiculopathy permitting neural decompression and maintenance of motion.

The clinical and radiographic outcomes in cervical ADR patients using the ProDisc-C device (DePuy Synthes, West Chester, PA, USA) with a 5-9 year follow-up were collected through a prospective registry, with retrospective analysis performed on 24 consecutive patients treated with cervical ADR by a single surgeon. All patients underwent single- or two-level ADR with the ProDisc-C device. Outcome measures included neck and arm pain (visual analogue scale), disability (neck disability index [NDI]), complications and secondary surgery rates. Flexion-extension cervical radiographs were performed to assess range of motion (ROM) of the device and adjacent segment disease (ASD). Average follow-up was 7.7 years. Neck and arm pain improved 60% and 79%, respectively, and NDI had an improvement of 58%. There were no episodes of device migration or subsidence. Mean ROM of the device was 6.4°. Heterotopic ossification was present in seven patients (37%). Radiographic ASD below the device developed in four patients (21%) (one single-level and three two-level ADR). No patient required secondary surgery (repeat operations at the index level or adjacent levels). Fourteen out of 19 patients (74%) were able to return to employment, with a median return to work time of 1.3 months. The ProDisc-C device for cervical ADR is a safe option for patients providing excellent clinical outcomes, satisfactory return to work rates and maintenance of segmental motion despite radiographic evidence of heterotopic ossification and ASD on long-term follow-up 27).

Types

Biomechanical analysis

Scarce references could be found and compared regarding the cervical ADR devices’ biomechanical differences that are consequently related to their different clinical results.

One fusion device (CJ cage system, WINNOVA) and three different cervical artificial discs (Prodisc-C Nova (DePuy Synthes), Discocerv (Scient’x/Alphatec), Baguera C (Spineart)) were inserted at C5-6 disc space inside the FE model and analyzed. Hybrid loading conditions, under bending moments of 1 Nm along flexion, extension, lateral bending and axial rotation with a compressive force of 50 N along the follower loading direction, were used in this study. Biomechanical behaviors such as segmental mobility, facet joint forces, and possible wear debris phenomenon inside the core were investigated.

The segmental motions as well as facet joint forces were exaggerated after ADR regardless of type of the devices. The Baguera C mimicked the intact cervical spine regarding the location of the center of rotation (COR) only during the flexion moment. It also showed a relatively wider distribution of the contact area and significantly lower contact pressure distribution on the core compared to the other two devices. A ‘lift off’ phenomenon was noted for other two devices according to the specific loading condition.

The mobile core artificial disc Baguera C can be considered biomechanically superior to other devices by demonstrating no ‘lift off’ phenomenon, and significantly lower contact pressure distribution on core 28).

Revision surgery and explantation

Between November 2008 and July 2016, 16 patients with prior implantation underwent removal of the Galileo-type disc prosthesis (Signus, Medizintechnik, Germany) due to a call back by industry. In 10 patients C-ADR was replaced with an alternative prosthesis, 6 patients received an ACDF. Duration of surgery, time to revision, surgical procedure, complication rate, neurological status, histological findings and outcome were examined in two institutions.

The C-ADR was successfully revised in all patients. Surgery was performed through the same anterior approach as the initial access. Duration of the procedure varied between 43 and 80min. Access-related complications included irritation of the recurrent nerve in one patient and mal-positioning of the C-ADR in another patient. Follow up revealed two patients with permanent mild/moderate neurologic deficits, NDI (neck disability index) ranged between 10 and 42%.

Anterior exposure of the cervical spine for explantation and revision of C-ADR performed through the initial approach has an overall complication rate of 18.75%. Replacements of the Galileo-type disc prosthesis with an alternative prosthesis or conversion to ACDF are both suitable surgical options without significant difference in outcome 29).

Case series

2017

As part of an FDA IDE trial, a single center collected prospective outcomes data on 47 patients randomized in a 1:1 ratio to ACDF or arthroplasty.

Success of both surgical interventions remained high at the 10-year interval. Both arthrodesis and arthroplasty demonstrated statistically significant improvements in neck disability index, visual analog scale neck and arm pain scores at all intervals including 7- and 10-year periods. Arthroplasty demonstrated an advantage in comparison to arthrodesis as measured by final 10-year NDI score (8 vs. 16, P = 0.0485). Patients requiring reoperation were higher in number in the arthrodesis cohort (32%) in comparison with arthroplasty (9%) (P = 0.055).

At 7 and 10 years, cervical arthroplasty compares favorably with ACDF as defined by standard outcomes scores in a highly selected population with radiculopathy 30).

2016

A total of 200 subjects underwent single-level activC® (Aesculap AG) implantation between C-3 and C-7 for the treatment of symptomatic degenerative disc disease. Clinical and radiographic assessments were performed preoperatively, intraoperatively, at discharge, and again at 6 weeks, 6 months, 1 year, 2 years, and 4 years. Radiographic evaluations were done by an independent core laboratory using a specific software for quantitative motion analysis.

Neck Disability Index (NDI) and visual analog scale (VAS) score for neck and arm pain decreased significantly from baseline to the 4-year follow-up. The mean improvement for NDI was 20, for VAS severity and frequency of neck pain 26.4 and 28, and for VAS severity and frequency of arm pain 30.7 and 35.1, respectively. The neurological situation improved for the majority of patients (86.4%); 76.1% of cases were asymptomatic. Subsequent surgical interventions were reported in 7% of the cases, including device removals in 3%. In 2.5% a subsidence greater than 3 mm was recorded; 1 of these cases also had a migration greater than 3 mm. No device displacement, expulsion, disassembly, loose or fractured device, osteolysis, or facet joint degeneration at the index level was observed. Segmental lordotic alignment changed from -2.4° preoperatively to -6.2° at 4 years, and postoperative height was maintained during the follow-up. Advanced HO (Grade III and IV) was present in 27.1% of the cases; 82.4% showed segmental mobility. A progression of radiographic adjacent-segment degeneration occurred in 28.2%, but only 4.5% required surgical treatment.

The activ C is a safe and effective device for cervical disc replacement confirming the encouraging results after cTDR. Clinical trial registration no.: NCT02492724 ( clinicaltrials.gov ) 31)


A total of 225 patients received the Mobi-C cervical total disc replacement device and 105 patients received ACDF. The Mobi-C and ACDF follow-up rates were 90.7% and 86.7%, respectively (p = 0.39), at 60 months. There was significant improvement in all outcome scores relative to baseline at all time points. The Mobi-C patients had significantly more improvement than ACDF patients in terms of Neck Disability Index score, SF-12 Physical Component Summary, and overall satisfaction with treatment at 60 months. The reoperation rate was significantly lower with Mobi-C (4%) versus ACDF (16%). There were no significant differences in the adverse event rate between groups.

Both cervical total disc replacement and ACDF significantly improved general and disease-specific measures compared with baseline. However, there was significantly greater improvement in general and disease-specific outcome measures and a lower rate of reoperation in the 2-level disc replacement patients versus ACDF control patients. Clinical trial registration no. NCT00389597 ( clinicaltrials.gov ) 32).


Twenty patients (12 females, 8 males; median age 45.6 ± 6.9 years) treated by ACDA (BryanDisc®, Medtronic, Minneapolis, USA) underwent plain functional radiography and kinematic MRI of the cervical spine at 3T before and 6 and 24 months after surgery.

A sagittal T2-weighted (T2w) 2D turbo spin echo (TSE) sequence and a 3D T2w dataset with secondary axial reconstruction were acquired. Signal intensity of all nonoperated discs was measured in regions of interest (ROI). Disc heights adjacent to the operated segment were measured. Range of motion (ROM) was evaluated and compared to plain functional radiographs. Clinical outcome was evaluated using the visual analog scale (VAS) for head, neck and radicular pain, and the neck disability index (NDI).

Mean ROM of the cervical spine on functional plain radiographs was 21.25 ± 8.19, 22.29 ± 4.82 and 26.0 ± 6.9 degrees preoperatively and at 6-month and 24-month follow-up, respectively. Mean ROM at MRI was 27.1 ± 6.78, 29.45 ± 9.51 and 31.95 ± 9.58 degrees, respectively. There was good correlation between both techniques. Follow-up examinations demonstrated no signs of progressive degenerative disc disease of adjacent levels. All patients had clinical improvement up to 24 months after surgery.

After ACDA, kinematic MRI allows evaluation of the ROM with excellent correlation to plain functional radiographs. Mid-term follow-up after ACDA is without evidence of progressive DDD of adjacent segments 33).


A prospective, multicenter, randomized, unblinded clinical trial. Patients with symptomatic degenerative disc disease were enrolled to receive 1- or 2-level treatment with either TDR as the investigational device or ACDF as the control treatment. There were 260 patients in the 1-level study (179 TDR and 81 ACDF patients) and 339 patients in the 2-level study (234 TDR and 105 ACDF patients). RESULTS At 5 years, the occurrence of subsequent surgical intervention was significantly higher among ACDF patients for 1-level (TDR, 4.5% [8/179]; ACDF, 17.3% [14/81]; p = 0.0012) and 2-level (TDR, 7.3% [17/234]; ACDF, 21.0% [22/105], p = 0.0007) treatment. The TDR group demonstrated significantly fewer index- and adjacent-level subsequent surgeries in both the 1- and 2-level cohorts.

Five-year results showed treatment with cervical TDR to result in a significantly lower rate of subsequent surgical intervention than treatment with ACDF for both 1 and 2 levels of treatment. Clinical trial registration no.: NCT00389597 ( clinicaltrials.gov ) 34).

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Update: Awake surgery

An awake craniotomy is a safe neurosurgical procedure that minimizes the risk of brain injury. During the course of this surgery, the patient is asked to perform motor or cognitive tasks, but some patients exhibit severe sleepiness.

For neurosurgery with an awake craniotomy, the critical issue is to set aside enough time to identify eloquentcortices by electrocortical stimulation (ECS). High gamma activity (HGA) ranging between 80 and 120 Hz on electrocorticogram (ECoG) is assumed to reflect localized cortical processing.

Indications

Gross total removal of glioma is limited by proximity to eloquent brain. Awake surgery allows for intraoperative monitoring to safely identify eloquent regions.


For a long time, the right hemisphere (RH) was considered as “non-dominant”, especially in right-handers. In neurosurgical practice, this dogma resulted in the selection of awake craniotomy with language mapping only for lesions of the left dominant hemisphere. Conversely, surgery under general anesthesia (possibly with motor mapping) was usually proposed for right lesions. However, when objective neuropsychological tests were performed, they frequently revealed cognitive and behavioral deficits following brain surgery, even in the RH. Therefore, to preserve an optimal quality of life, especially in patients with a long survival expectancy (as in low-grade gliomas), awake surgery with cortical and axonal electrostimulation mapping has recently been proposed for right tumors resection. Here, we review new insights gained from intraoperative stimulation into the pivotal role of the RH in movement execution and control, visual processes and spatial cognition, language and non-verbal semantic processing, executive functions (e.g. attention), and social cognition (mentalizing and emotion recognition). Such original findings, that break with the myth of a “non-dominant” RH, may have important implications in cognitive neurosciences, by improving our knowledge of the functional connectivity of the RH, as well as for the clinical management of patients with a right lesion. Indeed, in brain surgery, awake mapping should be considered more systematically in the RH. Moreover, neuropsychological examination must be achieved in a more systematic manner before and after surgery within the RH, to optimize the care by predicting the likelihood of functional recovery and by elaborating specific programs of rehabilitation 1).

Operations in eloquent areas

Awake craniotomy was introduced for surgical treatment of epilepsy, and has subsequently been used in patients with supratentorial tumors, intracranial arteriovenous malformationdeep brain stimulation, and mycotic aneurysms near critical regions of brain.

Patients are selected for awake craniotomy when the planned procedure involves eloquent areas of the brain, necessitating an awake, cooperative patient capable of undergoing neurocognitive testing, especially speech area, (Broca’s areaWernicke’s area) near motor stripthalamus, removal of brainstem tumors, some seizure surgery.

The critical issue is to set aside enough time to identify eloquent cortices by electrocortical stimulation (ECS). High gamma activity (HGA) ranging between 80 and 120 Hz on electrocorticogram (ECoG) is assumed to reflect localized cortical processing. In this report, we used realtime HGA mapping and functional magnetic resonance imaging (fMRI) for rapid and reliable identification of motor and language functions. Three patients with intra-axial tumors in their dominant hemisphere underwent preoperative fMRI and lesion resection with an awake craniotomy. All patients showed significant fMRI activation evoked by motor and language tasks. After the craniotomy, we recorded ECoG activity by placing subdural grids directly on the exposed brain surface. Each patient performed motor and language tasks and demonstrated realtime HGA dynamics in hand motor areas and parts of the inferior frontal gyrus. Sensitivity and specificity of HGA mapping were 100% compared to ECS mapping in the frontal lobe, which suggested HGA mapping precisely indicated eloquent cortices. The investigation times of HGA mapping was significantly shorter than that of ECS mapping. Specificities of the motor and language-fMRI, however, did not reach 85%. The results of HGA mapping was mostly consistent with those of ECS mapping, although fMRI tended to overestimate functional areas. This novel technique enables rapid and accurate functional mapping 2).

Awake craniotomy for glioma

Craniotomies for glioma resection under conscious sedation (CS) have been well-documented in the literature for gliomas that are in or adjacent to eloquent areas 3) 4) 5) 6) 7).

Awake surgery for glioma aims to maximize resection to optimize prognosis while minimizing the risk of postoperative deficits.

The oncological and functional results of awake glioma surgery during the learning curve are comparable to results from established centers. The use and utility of resection probability maps are well demonstrated. The return to work level is high 8).

AC with the input of the speech and language therapist (SLT) and an experienced neuro-physiotherapist (NP) is a key component in ensuring optimal functional outcomes for patients with gliomas in eloquently located areas 9).

5 aminolevulinic acid guidance during awake craniotomy

Corns et al. describe the case of a patient with recurrent left frontal GBM encroaching on Broca’s area (eloquent brain). Gross total resection of the tumour was achieved by combining two techniques, awake resection to prevent damage to eloquent brain and 5-ALA fluorescence guidance to maximise the extent of tumour resection.This technique led to gross total resection of all T1-enhancing tumour with the avoidance of neurological deficit. The authors recommend this technique in patients when awake surgery can be tolerated and gross total resection is the aim of surgery 10)

Contraindications

Uncooperative (very young or too old patient).

Confusion.

Speech deficit

Language barrier

Brain mapping

Electrocortical stimulation (ECS) is the gold standard for functional brain mapping during an awake craniotomy.

Awake craniotomy could be challenging because of unsecured airway with risks of vomitting, epileptic attacks or unstable level of consciousness. It is considered that the patient monitoring becomes more difficult when iMRI is performed because the patient’s face cannot be obsereved directly. We should remember that conscious level as well as respiration pattern may change during operation 11).

Awake craniotomy can be safely performed in a high-field (1.5 T) iMRI suite to maximize tumor resection in eloquent brain areas with an acceptable morbidity profile at 1 month 12).

The routine use of fMRI was not useful in identifying language sites as performed and, more importantly, practiced tasks failed to prevent neurological deficits following awake craniotomy procedures 13).

Management of anesthesia

The importance of minimizing pain and preparing patients thoroughly to reduce anxiety and maximize cooperation. Awake surgery is an excellent treatment modality for brain tumors with very positive perception by patients 14).

Different anesthetic combinations, including neurolept, propofol with or without opioid infusions, and asleep-awake-asleep techniques, have been reported for awake craniotomy. In all these techniques, respiratory depression has been reported as a complication.

see dexmedetomidine

Different protocols exist for anesthetic care during awake craniotomy based on monitored anesthesia care (MAC) or general anesthesia (asleep-awake-asleep technique). Nevertheless the administration of anesthetics, expectedly, is not without drawbacks, side effects and risks. A new approach for awake craniotomies emphasizes the need of adequate communication with patients 15).

Scalp block

see http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4236942/#ref11

Awake surgery with intraoperative brain mapping is highly recommended for patients with diffuse low grade gliomas in language areas, to maximise the extent of resection while preserving the integrity of functional networks and thus quality of life.

The picture naming test DO 80 is the gold standard for language assessment before, during, and after surgery.

Cognitive functioning is correlated with quality of life, itself linked with return to work.

The objective was to evaluate the significance of measuring naming speed, and its correlation with the return to professional activities. Two complementary studies are reported. In the first retrospective study, eleven patients were examined post-operatively. Five patients were selected because they were not able to resume their professional activities (“no return group 1”). They were compared with a control group of six patients who are working normally after surgery (“return group 1”). The eleven patients performed a global language and neuropsychological assessment, with a post-operative median follow-up of 35 months. In a subsequent prospective study, twelve patients were examined pre-operatively and post-operatively. Six patients who were not able to return to work (“no return group 2”) were compared with a control group of six patients who were working normally after the surgery (“return group 2”). The twelve patients performed a pre and post-operative language assessment, with a median follow-up of 9 months. Our results show, for the first time, that naming speed is significantly correlated with a major criterion of quality of life: the return to professional activities. There were no differences between the two groups regarding other measures of cognition. Assessing naming times, and not only naming accuracy, is essential in the management of low-grade glioma patients, before, during, and after surgery, to preserve their quality of life by resuming their previous professional activity. Our results have fundamental implications concerning the comprehension of language processing and its relationship with cognitive functioning 16).

Cost effectiveness

Retrospective analysis of a cohort of 17 patients with perirolandic gliomas who underwent an AC with DCS were case-control matched with 23 patients with perirolandic gliomas who underwent surgery under GA with neuromonitoring (ie, motor-evoked potentials, somatosensory-evoked potentials, phase reversal). Inpatient costs, quality-adjusted life years (QALY), extent of resection, and neurological outcome were compared between the groups.

Total inpatient expense per patient was ${\$}$ 34 804 in the AC group and ${\$}$ 46 798 in the GA group ( P = .046). QALY score for the AC group was 0.97 and 0.47 for the GA group ( P = .041). The incremental cost per QALY for the AC group was ${\$}$ 82 720 less than the GA group. Postoperative Karnofsky performance status was 91.8 in the AC group and 81.3 in the GA group (P = .047). Length of hospitalization was 4.12 days in the AC group and 7.61 days in the GA group ( P = .049).

The total inpatient costs for awake craniotomies were lower than surgery under GA. This study suggests better cost effectiveness and neurological outcome with awake craniotomies for perirolandic gliomas 17).

Case series

2017

Motomura et al. retrospectively reviewed the records of 33 consecutive patients with glial tumors in the eloquent brain areas who underwent awake surgery using iMRI. Volumetric analysis of MRI studies was performed. The pre-, intra-, and postoperative tumor volumes were measured in all cases using MRI studies obtained before, during, and after tumor resection. RESULTS Intraoperative MRI was performed to check for the presence of residual tumor during awake surgery in a total of 25 patients. Initial iMRI confirmed no further tumor resection in 9 patients (36%) because all observable tumors had already been removed. In contrast, intraoperative confirmation of residual tumor during awake surgery led to further tumor resection in 16 cases (64%) and eventually an EOR of more than 90% in 8 of 16 cases (50%). Furthermore, EOR benefiting from iMRI by more than 15% was found in 7 of 16 cases (43.8%). Interestingly, the increase in EOR as a result of iMRI for tumors associated mainly with the insular lobe was significantly greater, at 15.1%, than it was for the other tumors, which was 8.0% (p = 0.001).

This study revealed that combining awake surgery with iMRI was associated with a favorable surgical outcome for intrinsic brain tumors associated with eloquent areas. In particular, these benefits were noted for patients with tumors with complex anatomy, such as those associated with the insular lobe 18).

2016

Four illustrative cases demonstrate the efficacy of using a tablet computer platform for advanced language mapping testing with sophisticated language paradigms, and the spatial agreement between intraoperative mapping and preoperative fMRI results. The testing platform substantially improved the ability of the surgeon to detect and characterize language deficits. Use of a written word generation task to assess language production helped confirm areas of speech apraxia and speech arrest that were inadequately characterized or missed with the use of traditional paradigms, respectively. Preoperative fMRI of the analogous writing task was also assistive, displaying excellent spatial agreement with intraoperative mapping in all 4 cases. Sole use of traditional testing paradigms can be limiting during awake craniotomy procedures. Comprehensive assessment of language function will require additional use of more sophisticated and ecologically valid testing paradigms. The platform presented here provides a means to do so 19).

2015

Thirty-seven patients with brain tumor who underwent awake craniotomy were included in this study. Prior to craniotomy, the patient evaluated cognitive status, and during the surgery, each patient’s performance and attitude toward cognitive tasks were recorded by neuropsychologists.

The present findings showed that the construction and calculation abilities of the patients were moderately correlated with their sleepiness.

These results indicate that the preoperative cognitive functioning of patients was related to their sleepiness during the awake craniotomy procedure and that the patients who exhibited sleepiness during an awake craniotomy had previously experienced reduced functioning in the parietal lobe 20).

2009

From 1998 to 2007, 79 consecutive fully awake craniotomy (FAC)s for resection primary supratentorial brain tumors (PSBT) near or in eloquent brain areas (EBA), performed by a single surgeon, were prospectively followed. Two groups were defined based on time period and surgical team: group A operated on from March 1998 to July 2004 without a multidisciplinary team and group B operated on from August 2004 to October 2007 in a multidisciplinary setting. For both time periods, two groups were defined: group I had no previous history of craniotomy, while group II had undergone a previous craniotomy for a PSBT. Forty-six patients were operated on in group A, 46 in group B, 49 in group I and 30 in group II. Psychological assessment and selection were obligatory. The preferred anesthetic procedure was an intravenous high-dose opioid infusion (Fentanil 50 microg, bolus infusion until a minimum dose of 10 microg/kg). Generous scalp and periosteous infiltrations were performed. Functional cortical mapping was performed in every case. Continuous somato-sensory evoked potentials (SSEPs) and phase reversal localization were available in 48 cases. Standard microsurgical techniques were performed and monitored by continuous clinical evaluation.

Clinical data showed differences in time since clinical onset (p < 0.001), slowness of thought (p = 0.02) and memory deficits (p < 0.001) between study periods and also time since recent seizure onset for groups I and II (p = 0.001). Mean tumor volume was 51.2 +/- 48.7 cm3 and was not different among the four groups. The mean extent of tumor reduction was 90.0 +/- 12.7% and was similar for the whole series. A trend toward a larger incidence of glioblastoma multiforme occurred in group B (p = 0.05) and I (p = 0.04). Recovery of previous motor deficits was observed in 75.0% of patients, while motor worsening in 8.9% of cases. Recovery of semantic language deficits, control of refractory seizures and motor worsening were statistically more frequent in group B (p = 0.01). Satisfaction with the procedure was reported by 89.9% of patients, which was similar for all groups. Clinical complications were minimal, and surgical mortality was 1.3%.

These data suggest that FAC is safe and effective for the resection of PSBT in EBA as the main technique, and in a multidisciplinary context is associated with greater clinical and physiological monitoring. The previous history of craniotomy for PSBT did not seem to influence the outcome21).

1)

Vilasboas T, Herbet G, Duffau H. Challenging the myth of right “non-dominant” hemisphere: Lessons from cortico-subcortical stimulation mapping in awake surgery and surgical implications. World Neurosurg. 2017 Apr 15. pii: S1878-8750(17)30516-8. doi: 10.1016/j.wneu.2017.04.021. [Epub ahead of print] Review. PubMed PMID: 28419879.

2)

Kamada K, Ogawa H, Kapeller C, Prueckl R, Guger C. Rapid and low-invasive functional brain mapping by realtime visualization of high gamma activity for awake craniotomy. Conf Proc IEEE Eng Med Biol Soc. 2014 Aug;2014:6802-6805. PubMed PMID: 25571558.

3)

Bejjani GK, Nora PC, Vera PL, Broemling L, Sekhar LN. The predictive value of intraoperative somatosensory evoked potential monitoring: Review of 244 procedures. Neurosurgery 1998;43:491-8.

4)

De Benedictis A, Mortiz-Gasser S, Duffau H. Awake mapping optimizes the extent of resection for low-grade gliomas in eloquent areas. Neurosurgery 2010;66:1074-84.

5)

Peruzzi P, Bergese SD, Viloria A, Puente EG, Abdel-Rasoul M, Chiocca EA. A retrospective cohort-matched comparison of conscious sedation versus general anesthesia for supratentorial glioma resection. Clinical article. J Neurosurg 2011;114:633-9.

6)

Taylor MD, Bernstein M. Awake craniotomy with brain mapping as the routine surgical approach to treating patients with supratentorial intraaxial tumors: A prospective trial of 200 cases. J Neurosurg 1999;90:35-41.

7)

Wiedemayer H, Sandalcioglu IE, Armbruster W, Regel J, Schaefer H, Stolke D. False negative findings in intraoperative SEP monitoring: Analysis of 658 consecutive neurosurgical cases and review of published reports. J Neurol Neurosurg Psychiatry 2004;75:280-6.

8)

Mandonnet E, De Witt Hamer P, Poisson I, Whittle I, Bernat AL, Bresson D, Madadaki C, Bouazza S, Ursu R, Carpentier AF, George B, Froelich S. Initial experience using awake surgery for glioma: oncological, functional, and employment outcomes in a consecutive series of 25 cases. Neurosurgery. 2015 Apr;76(4):382-9. doi: 10.1227/NEU.0000000000000644. PubMed PMID: 25621981.

9)

Trimble G, McStravick C, Farling P, Megaw K, McKinstry S, Smyth G, Law G, Courtney H, Quigley G, Flannery T. Awake craniotomy for glioma resection: Technical aspects and initial results in a single institution. Br J Neurosurg. 2015 Jul 13:1-7. [Epub ahead of print] PubMed PMID: 26168299.

10)

Corns R, Mukherjee S, Johansen A, Sivakumar G. 5-aminolevulinic acid guidance during awake craniotomy to maximise extent of safe resection of glioblastoma multiforme. BMJ Case Rep. 2015 Jul 15;2015. pii: bcr2014208575. doi: 10.1136/bcr-2014-208575. PubMed PMID: 26177997.

11)

Kamata K, Wada K, Kinoshita M, Nomura M, Ozaki M. [A case of respiratory arrest during intraoperative magnetic resonance imaging (iMRI) for awake craniotomy]. Masui. 2014 Aug;63(8):907-10. Japanese. PubMed PMID: 25199330.

12)

Maldaun MV, Khawja SN, Levine NB, Rao G, Lang FF, Weinberg JS, Tummala S, Cowles CE, Ferson D, Nguyen AT, Sawaya R, Suki D, Prabhu SS. Awake craniotomy for gliomas in a high-field intraoperative magnetic resonance imaging suite: analysis of 42 cases. J Neurosurg. 2014 Oct;121(4):810-7. doi: 10.3171/2014.6.JNS132285.Epub 2014 Aug 8. PubMed PMID: 25105702.

13)

Trinh VT, Fahim DK, Maldaun MV, Shah K, McCutcheon IE, Rao G, Lang F, Weinberg J, Sawaya R, Suki D, Prabhu SS. Impact of Preoperative Functional Magnetic Resonance Imaging during Awake Craniotomy Procedures for Intraoperative Guidance and Complication Avoidance. Stereotact Funct Neurosurg. 2014 Sep 18;92(5):315-322. [Epub ahead of print] PubMed PMID: 25247627.

14)

Beez T, Boge K, Wager M, Whittle I, Fontaine D, Spena G, Braun S, Szelényi A, Bello L, Duffau H, Sabel M; European Low Grade Glioma Network. Tolerance of awake surgery for glioma: a prospective European Low Grade Glioma Network multicenter study. Acta Neurochir (Wien). 2013 Jul;155(7):1301-8. doi: 10.1007/s00701-013-1759-0. Epub 2013 May 21. PubMed PMID: 23689968.

15)

Hansen E, Seemann M, Zech N, Doenitz C, Luerding R, Brawanski A. Awake craniotomies without any sedation: The awake-awake-awake technique. Acta Neurochir (Wien) 2013;155:1417–24.

16)

Moritz-Gasser S, Herbet G, Maldonado IL, Duffau H. Lexical access speed is significantly correlated with the return to professional activities after awake surgery for low-grade gliomas. J Neurooncol. 2012 May;107(3):633-41. doi: 10.1007/s11060-011-0789-9. Epub 2012 Jan 24. PubMed PMID: 22270847.

17)

Eseonu CI, Rincon-Torroella J, ReFaey K, Quiñones-Hinojosa A. The Cost of Brain Surgery: Awake vs Asleep Craniotomy for Perirolandic Region Tumors. Neurosurgery. 2017 Mar 15. doi: 10.1093/neuros/nyx022. [Epub ahead of print] PubMed PMID: 28327904.

18)

Motomura K, Natsume A, Iijima K, Kuramitsu S, Fujii M, Yamamoto T, Maesawa S, Sugiura J, Wakabayashi T. Surgical benefits of combined awake craniotomy and intraoperative magnetic resonance imaging for gliomas associated with eloquent areas. J Neurosurg. 2017 Jan 6:1-8. doi: 10.3171/2016.9.JNS16152. [Epub ahead of print] PubMed PMID: 28059650.

19)

Morrison MA, Tam F, Garavaglia MM, Golestanirad L, Hare GM, Cusimano MD, Schweizer TA, Das S, Graham SJ. A novel tablet computer platform for advanced language mapping during awake craniotomy procedures. J Neurosurg. 2016 Apr;124(4):938-44. doi: 10.3171/2015.4.JNS15312. Epub 2015 Oct 16. PubMed PMID: 26473779.

20)

Itoi C, Hiromitsu K, Saito S, Yamada R, Shinoura N, Midorikawa A. Predicting sleepiness during an awake craniotomy. Clin Neurol Neurosurg. 2015 Oct 31;139:307-310. doi: 10.1016/j.clineuro.2015.10.033. [Epub ahead of print] PubMed PMID: 26571456.

21)

Pereira LC, Oliveira KM, L’Abbate GL, Sugai R, Ferreira JA, da Motta LA. Outcome of fully awake craniotomy for lesions near the eloquent cortex: analysis of a prospective surgical series of 79 supratentorial primary brain tumors with long follow-up. Acta Neurochir (Wien). 2009 Oct;151(10):1215-30. doi: 10.1007/s00701-009-0363-9. PubMed PMID: 19730779.

Update: Midline suboccipital subtonsillar approach

Marcos Tatagiba et al. described the surgical anatomy of the midline suboccipital subtonsillar approach to the hypoglossal canal. This approach includes a midline suboccipital craniotomy, dorsal opening of the foramen magnum and elevation of ipsilateral cerebellar tonsil to expose the hypoglossal nerve and its canal. The midline subtonsillar approach permits a straight primary intradural view to the hypoglossal canal. There is no necessity of condylar resections 1) 2).

It offers excellent access with a panoramic view of the cerebellomedullary cistern and its structures and therefore can be useful for a number of different pathologies in the lower petroclival region 3).


A study was performed on three alcohol (ETOH)-fixed specimens (6 sides), and the technique of the approach was highlighted. The tonsillar retraction needed to view the important structures was measured. Additionally, the records of 31 patients who underwent the STA procedure were evaluated and provide three clinical cases as examples.

Tonsillar retraction of 0.3cm (SD±0.1cm) exposed the PICA with its telo-velo-tonsillar and cortical branches. Retraction of 0.4cm (SD±0.2cm) exposed the spinal root of CN XI. Retraction of 0.9cm (SD±0.01cm) exposed the hypoglossal canal. Retraction of 1.3cm (SD±0.2cm) exposed the root exit zone of the glossopharyngeal nerve. Retraction of 1.6cm (SD±0.3cm) exposed the jugular foramen (JF), and retraction of 2.4cm (SD±0.2cm) exposed the inner auditory canal (IAC). In all of the selected cases, the pathology could be reached and exposed using the STA.

They recommend STA as a straightforward, easy-to-learn and therefore time-saving and safe procedure compared with other standard approaches to the cerebellomedullary cistern and its pathologies 4).

Indications

Glossopharyngeal neuralgia5).

Anterior, anterolateral, and posterior Foramen magnum meningioma6).

There was no significant postoperative complication in the remainder of the patientes, and their conditions improved after surgery 7).

Hypoglossal canal meningioma.

Case reports

2015

Two patients with exophytic or focal lesions in the inferior half of the medulla, who underwent surgery by suboccipital midline subtonsillar approach. This approach was not specifically described to reach MO before, and they found that the lesions produced a mild elevation of the tonsils providing a wide surgical view from the medulla to the foramen of Luchska laterally, and up to the middle cerebellar peduncle, offering a wide and safe access 8).

2010

A 36-year-old woman presented with increased intracranial pressure and cerebellar signs without hypoglossal nerve palsy. Magnetic resonance imaging showed a predominantly cystic mass with a fluid-fluid level in the foramen magnum region extending into the hypoglossal canal. The intracranial tumor was largely removed via a midline suboccipital subtonsillar approach, leaving only a tiny residue in the hypoglossal canal. Histology confirmed a schwannoma with relative hypervascularity. Twenty months later, the tumor recurred and presented as a multicystic dumbbell-shaped lesion, extending intra- and extracranially through the enlarged hypoglossal canal. A complete resection of the intracranial and intracanalicular parts of the tumor was achieved with a small extracranial remnant treated by radiosurgery. Histology revealed a focal increased K(i)67 proliferative index. In this report, we discuss the possible reasons for the absence of hypoglossal nerve palsy and the potential mechanism of the formation of the fluid-fluid level, and we consider the treatment of this lesion 9).

1)

Tatagiba M, Koerbel A, Roser F. The midline suboccipital subtonsillar approach to the hypoglossal canal: surgical anatomy and clinical application. Acta Neurochir (Wien). 2006 Sep;148(9):965-9. Epub 2006 Jul 5. Review. PubMed PMID: 16817032.
2)

Herlan S, Roser F, Ebner FH, Tatagiba M. The midline suboccipital subtonsillar approach to the cerebellomedullary cistern: how I do it. Acta Neurochir (Wien). 2017 Jul 22. doi: 10.1007/s00701-017-3270-5. [Epub ahead of print] PubMed PMID: 28735380.
3) , 4)

Herlan S, Ebner FH, Nitz A, Hirt B, Tatagiba M, Roser F. The midline suboccipital subtonsillar approach to the cerebellomedullary cistern and its structures: anatomical considerations, surgical technique and clinical application. Clin Neurol Neurosurg. 2014 Oct;125:98-105. doi: 10.1016/j.clineuro.2014.07.029. Epub 2014 Jul 27. PubMed PMID: 25113380.
5)

Roser F, Ebner FH, Schuhmann MU, Tatagiba M. Glossopharyngeal neuralgia treated with an endoscopic assisted midline suboccipital subtonsillar approach: technical note. J Neurol Surg A Cent Eur Neurosurg. 2013 Sep;74(5):318-20. doi: 10.1055/s-0032-1327447. Epub 2012 Oct 5. PubMed PMID: 23042141.
6)

Dogan M, Dogan DG. Foramen magnum meningioma: The midline suboccipital subtonsillar approach. Clin Neurol Neurosurg. 2016 Aug;147:116. doi: 10.1016/j.clineuro.2016.05.025. Epub 2016 Jun 6. PubMed PMID: 27321572.
7)

Dobrowolski S, Ebner F, Lepski G, Tatagiba M. Foramen magnum meningioma: The midline suboccipital subtonsillar approach. Clin Neurol Neurosurg. 2016 Jun;145:28-34. doi: 10.1016/j.clineuro.2016.02.027. Epub 2016 Apr 2. PubMed PMID: 27064859.
8)

Rabadán AT, Campero A, Hernández D. Surgical Application of the Suboccipital Subtonsillar Approach to Reach the Inferior Half of Medulla Oblongata Tumors in Adult Patients. Front Surg. 2016 Jan 13;2:72. doi: 10.3389/fsurg.2015.00072. eCollection 2015. PubMed PMID: 26793713; PubMed Central PMCID: PMC4710703.
9)

Li WC, Hong XY, Wang LP, Ge PF, Fu SL, Luo YN. Large cystic hypoglossal schwannoma with fluid-fluid level: a case report. Skull Base. 2010 May;20(3):193-7. doi: 10.1055/s-0029-1246219. PubMed PMID: 21318038; PubMed Central PMCID: PMC3037104.

11TH Hands-on Course on Neurosurgical Approaches

VALENCIA 2017
OCTOBER, 24th-27th
Inscripción on-line:
www.neurosurgeryvalencia.com

DIRECTOR DEL CURSO
José M. González Darder

GUEST FACULTY
Radim Lipina

FACULTY
José Hinojosa Mena-Bernal
Tomáš Hrbáč
Vicent Quilis-Quesada
Luis Real Peña
Javier Sendra Tello
Fernando Talamantes

Esteban Vega Torres

DESCARGAR PROGRAMA

Curso auspiciado por la Sociedad Española de Neurocirugía (SENEC)

Solicitado reconocimiento como “Actividad de Interés Sanitario” por la Consellería de Sanitat Universal y Salut Pública

ORGANIZA

Departamento de Neurocirugía
Hospital Clínico de Valencia

SEDE

PATROCINA