A Different Perspective After Brain Injury: A Tilted Point of View (After Brain Injury: Survivor Stories)

A Different Perspective After Brain Injury: A Tilted Point of View (After Brain Injury: Survivor Stories)
By Christopher Yeoh

A Different Perspective After Brain Injury: A Tilted Point of View (After Brain Injury: Survivor Stories)

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Whilst preparing for his travel adventures into a world he had yet to explore, Christopher Yeoh was involved in a road traffic accident and experienced something few others would be “privileged” to witness. Eight days in a coma, more than a year in and out of hospital and a gradual re-introduction to the world of work.

A Different Perspective After Brain Injury: A Tilted Point of View is written entirely by the survivor, providing an unusually introspective and critical personal account of life following a serious blow to the head. It charts the initial insult, early rehabilitation, development of understanding, the return of emotion, moments of triumph and regression into depression, the exercise of reframing how a brain injury is perceived and a return to work. It also describes the mental adjustments of awareness and acceptance alongside the physical recovery process.

Readily accessible to the general public, this book will also be of particular interest to professionals involved in the care of people who have had significant brain injuries, brain injury survivors, their families and friends and also those who fund and organise health and social care. This unique author account will provide a degree of understanding of what living with a hidden disability is really like.


Product Details

  • Published on: 2017-06-20
  • Original language: English
  • Binding: Hardcover
  • 154 pages

Editorial Reviews

Review

‘This very engaging book, written by a high functioning survivor of a traumatic brain injury, gives an introspective and critical account of what it actually feels like to suffer a brain injury and ‘come through the other side’. Christopher Yeoh integrates his phenomenological experience of brain injury with science, literature, autobiography, and philosophy, resulting in an extremely readable account of his experience. It provides a real ‘insider’s view’ of brain injury not possible to capture in a purely academic textbook. For this reason, the book will be of huge importance not only to the individuals and their families affected by brain injury, but also the clinicians involved in their care and rehabilitation.’ Rudi Coetzer, Consultant Neuropsychologist, North Wales Brain Injury Service, Betsi Cadwaladr UHB NHS Wales and Senior Lecturer in Clinical Neuropsychology, School of Psychology, Bangor University.

‘Christopher’s poignant narrative of his recovery and rehabilitation shows how personal characteristics and social resources interact to overcome the serious aftermath of severe traumatic brain injury. This is a balanced and insightful account of loss, challenge and triumph. He writes with humility and humour, whilst never masking the devastation the injury caused for him and his loved ones. Many inspiring books are written by survivors; A Different Perspective After Brain Injury will strike a chord with people grappling with changes to self in the context of ANY major life change. This is also an invaluable resource for clinicians, researchers and educators who seek a deeper understanding of the experience of brain injury.’ – Professor Tamara Ownsworth, School of Applied Psychology, Griffith University, Australia

About the Author

Christopher Yeoh is a holder of an LLB and LLM from the London School of Economics. He continues to practice securities law as a solicitor of England and Wales at a major global law firm.

After his adventure he now runs a multi award winning food and travel blog at quieteating.com and is a featured photographer in the Telegraph and Sunday Times newspapers. His photos have also been featured in brochures by the luxury travel company, Audley Travel.

As an action man he was previously an avid triathlete and a national award winning karateka. Now he prefers a slower pace of life by writing and irritating people with his camera.

Life after brain injury is not something less but just something different.

The Broca-Wernicke Doctrine: A Historical and Clinical Perspective on Localization of Language Functions

The Broca-Wernicke Doctrine: A Historical and Clinical Perspective on Localization of Language Functions
By Geert-Jan Rutten

The Broca-Wernicke Doctrine: A Historical and Clinical Perspective on Localization of Language Functions

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This book discusses theories that link functions to specific anatomical brain regions. The best known of these are the Broca and Wernicke regions, and these have become synonyms for the location of productive and receptive language functions respectively. This Broca-Wernicke model has proved to be such a powerful concept that is remains the predominant view in modern clinical practice. What is fascinating, however, is that there is little evidence for this strictly localist view on language functions. Modern neuroscience and numerous clinical observations in individual patients show that language functions are represented in complex and ever-changing neural networks. It is fair to say that the model is wrong, and that Broca’s and Wernicke’s areas in their classic forms do not exist.

This is a fascinating paradox: why do neurologists and neurosurgeons continue to use these iconic language models in everyday decision-making? In this book, the author uses his background as a neurosurgeon and a neuroscientist to provide some answers to this question.

The book acquaints clinicians and researchers with the many different aspects of language representation in the brain. It provides a historical overview of functional localisation, as well as insights into the misjudgements that have kept the localist doctrine alive. It creates an awareness of the need to integrate clinical observations and neuroscientific theories if we want to progress further in clinical language research and patient care.


Product Details

  • Published on: 2017-06-19
  • Original language: English
  • Number of items: 1
  • Dimensions: 9.30″ h x .0″ w x 6.10″ l,
  • Binding: Hardcover
  • 306 pages

Update: Cervical laminoplasty

Cervical laminoplasty is an established treatment for cervical myelopathy.

Fields et al., 1) observed in their randomized study comparing the effects of cervical laminectomy and laminoplasty in the rabbit, that laminectomized animals had poorer clinical outcome at 3 months post-operatively, associated with statistically significant angular deformity.

Similarly, Baisden et al., 2) , using a goat model, concluded that laminoplasty is superior to laminectomy in maintaining sagittal cervical alignment and preventing spinal deformities. The removal of bony and ligamentous structures of the posterior cervical spine might alter the biomechanics of the vertebral column and predispose to instability.

History

The first laminoplasty technique was the modification of Kirita’s technique for laminectomy, in which the laminae were thinned and then partially removed in the midline using an air drill. The lateral edges of the laminae close to the pedicles were further thinned until the laminae could be bent and lifted up. It was considered important to lift multiple laminae expeditiously so that multiple segments of the cord could be simultaneously decompressed. The laminae were then removed with scissors 3)).

Based on this technique, Oyama et al. developed z-plasty method of laminoplasty. After thinning the laminae, z-shaped cuts were made in each laminae, which were lifted and then fixed with sutures to reconstruct the expanded spinal canal. They reported that all the 15 cases were neurologically improved after the operation 4)).

Tsuji reported a variation of en bloc laminectomy in which laminae were cut bilaterally along the imaginary line separating laminar arches and articular processes and made completely free from their bony attachments. The lamiae were reflected as a flap and then permitted to float on the cord without fixing sutures or bone grafting 5).

Expansive open-door laminoplasty was devised by Hirabayashi et al. in 1977, as relatively easier, safer, and better than the ordinary cervical laminectomy from the standpoint of structural mechanics of the cervical spine.

Operative results in the patients with cervical OPLL, spondylosis, and canal stenosis were satisfactory, and optimal widening of the AP diameter of the spinal canal is considered to be over 4 mm. From this procedure a bilateral, open-door laminoplasty has been devised for extensive exploration at the intradural space.

Cervical laminoplasty was devised to avoid problems associated with laminectomy such as postoperative segmental instability, kyphosis, perineural adhesions, and late neurological deterioration 6).

Kurokawa et al. developed spinous process splitting laminoplasty, in which the spinous processes and laminae are split in the midline and hinges are made bilaterally along the lateral borders of the laminae, which are lifted bilaterally 7)).

This is also called double-door laminoplasty 8), French-window 9) or French door laminoplasty 10)

There are multiple variations, many advocating the use of allograft, but for the best technique controversy persists.

Complications

Neck pain

Axial neck pain after C3-6 laminoplasty has been reported to be significantly lesser than that after C3-7 laminoplasty because of the preservation of the C-7 spinous process and the attachment of nuchal muscles such as the trapezius and rhomboideus minor, which are connected to the scapula. The C-6 spinous process is the second longest spinous process after that of C-7, and it serves as an attachment point for these muscles. The effect of preserving the C-6 spinous process and its muscular attachment, in addition to preservation of the C-7 spinous process, on the prevention of axial neck pain is not well understood. The purpose of the current study was to clarify whether preservation of the paraspinal muscles of the C-6 spinous process reduces postoperative axial neck pain compared to that after using nonpreservation techniques.

Montano et al. studied 60 patients who underwent C3-6 double-door laminoplasty for the treatment of cervical spondylotic myelopathy or cervical ossification of the posterior longitudinal ligament; the minimum follow-up period was 1 year. Twenty-five patients underwent a C-6 paraspinal muscle preservation technique, and 35 underwent a C-6 nonpreservation technique. A visual analog scale (VAS) and VAS grading (Grades I-IV) were used to assess axial neck pain 1-3 months after surgery and at the final follow-up examination. Axial neck pain was classified as being 1 of 5 types, and its location was divided into 5 areas. The potential correlation between the C-6/C-7 spinous process length ratio and axial neck pain was examined.

The mean VAS scores (± SD) for axial neck pain were comparable between the C6-preservation group and the C6-nonpreservation group in both the early and late postoperative stages (4.1 ± 3.1 vs 4.0 ± 3.2 and 3.8 ± 2.9 vs 3.6 ± 3.0, respectively). The distribution of VAS grades was comparable in the 2 groups in both postoperative stages. Stiffness was the most prevalent complaint in both groups (64.0% and 54.5%, respectively), and the suprascapular region was the most common site in both groups (60.0% and 57.1%, respectively). The types and locations of axial neck pain were also similar between the groups. The C-6/C-7 spinous process length ratios were similar in the groups, and they did not correlate with axial neck pain. The reductions of range of motion and changes in sagittal alignment after surgery were also similar.

The C-6 paraspinal muscle preservation technique was not superior to the C6-nonpreservation technique for preventing postoperative axial neck pain 11).

Case series

2017

Thirty-two consecutive patients (19 male, 13 female, average age 66 yr) from a prospective outcome registry that underwent cervical laminoplasty between 2009 and 2013 were reviewed. Computed tomography (CT) scan was performed immediately postoperatively and at 6-mo follow-up. Parameters included patient perception of outcome, Nurick score, Neck Disability Index (NDI), visual analog scale for neck pain, and SF-36.

On retrospective analysis, all patients felt improved at 3 mo postoperatively; at 2 yr, this rate was 91%. Improvements were seen in Nurick scores, from 3.16 ± 0.9 preoperatively to 1.94 ± 0.8 at 2 yr; NDI score from 28.7% ± 9% preoperatively to 20.8% ± 9.6% at 2 yr; visual analog scale from 2.8 ± 1.2 preoperatively to 1.7 ± 0.9 at 2 yr; and SF-36 physical component summary from 27.9 ± 10 preoperatively to 37.8 ± 11.9 at 2 yr. All values reached significance at all follow-up points ( P < .05) with the exception of 6-mo NDI values ( P = .062). No C5 palsy, graft complications, or reclosure was observed in any patient during the follow-up period.

Laminoplasty with autograft is a safe and effective method to treat cervical myelopathy, with good medium-term clinical outcome. No reclosures were observed. Bony fusion was seen in all cases on CT scan. The study found good outcomes in the performance of open door laminoplastywithout hardware, in the treatment of cervical stenosis 12).

2016

Sakaura et al., reported that the presence of chronic kidney disease (CKD) and/or extended abdominal aortic calcification was associated with significantly worse clinical outcomes after posterior lumbar interbody fusion. CKD is one of the highest risk factors for systemic atherosclerosis. Therefore, impaired blood flow due to atherosclerosis could exacerbate degeneration of the cervical spine and neural tissue. However, there has been no report of a study evaluating the deleterious effects of CKD and atherosclerosis on the outcomes after decompression surgery for cervical spondylotic myelopathy.

They analyzed data from 127 consecutive cases involving patients who underwent cervical laminoplasty for CSM and met their inclusion criteria. Stage 3-4 CKD was present as a preoperative comorbidity in 44 cases. Clinical status was assessed using the Japanese Orthopaedic Association (JOA) cervical myelopathy evaluation questionnaire before surgery and 2 years postoperatively. As a marker of systemic atherosclerosis, the presence of aortic arch calcification (AoAC) was assessed on preoperative chest radiographs.

AoAC was found on preoperative chest radiographs in 40 of 127 patients. Neither CKD nor AoAC had a statistically significant deleterious effect on preoperative JOA score. However, CKD and AoAC were significantly associated with reductions in both the JOA score recovery rate (mean 36.1% in patients with CKD vs 44.7% in those without CKD; 26.0% in patients with AoAC vs 48.9% in those without AoAC) and the change in JOA score at 2 years after surgery (mean 2.3 points in patients with CKD vs 3.1 points in those without CKD; 2.1 points for patients with AoAC vs 3.2 points for those without AoAC). A multivariate regression analysis showed that AoAC was a significant independent predictor of poor outcome with respect to both for the difference between follow-up and preoperative JOA scores and the JOA score recovery rate.

CKD and AoAC were associated with increased rates of poor neurological outcomes after laminoplasty for CSM, and AoAC was a significant independent predictive factor for poor outcome 13).

1)

Fields MF, Hoshijima K, Feng AHP, et al. A biomechanical, radiologic, and clinical comparison of outcome after multilevel cervical laminectomy or laminoplasty in the rabbit. Spine. 2000;25(22):2925–2931. doi: 10.1097/00007632-200011150-00015.
2)

Baisden J, Voo LM, Cusick JF, Pintar FA, Yoganandan N. Evaluation of cervical laminectomy and laminoplasty. A longitudinal study in the goat model. Spine (Phila Pa 1976). 1999 Jul 1;24(13):1283-8; discussion 1288-9. PubMed PMID: 10404568.
3)

Kirita Y, Miyazaki K, Hayashi T, Nosaka K, Shima M, Yamamura H, Tamaki S: [Ossification of posterior longitudinal ligament of the cervical spine]. Rinsho Seikeigeka 10: 1077– 1085, 1975. (Japanese
4)

Oyama M, Hattori S, Moriwaki N, Nitta S: [A new method of cervical laminectomy]. Chuubu Nippon Seikeigeka Gakkai Zasshi 16: 792– 794, 1973. (Japanese
5)

Tsuji H. Laminoplasty for patients with compressive myelopathy due to so-called spinal canal stenosis in cervical and thoracic regions. Spine (Phila Pa 1976). 1982 Jan-Feb;7(1):28-34. PubMed PMID: 7071659.
6)

Hirabayashi K, Watanabe K, Wakano K, Suzuki N, Satomi K, Ishii Y. Expansive open-door laminoplasty for cervical spinal stenotic myelopathy. Spine (Phila Pa 1976). 1983 Oct;8(7):693-9. PubMed PMID: 6420895.
7)

Kurokawa T, Tsuyama N, Tanaka H, Kobayashi M, Machida H, Nakamura K, Iizuka T, Hoshino Y: [Enlargement of spinal canal by the sagittal splitting of spinous processes]. Bessatsu Seikeigeka 2: 234– 240, 1982. (Japanese
8)

Seichi A, Takeshita K, Ohishi I, Kawaguchi H, Akune T, Anamizu Y, Kitagawa T, Nakamura K. Long-term results of double-door laminoplasty for cervical stenotic myelopathy. Spine (Phila Pa 1976). 2001 Mar 1;26(5):479-87. PubMed PMID: 11242374.
9)

Hukuda S, Ogata M, Mochizuki T, Shichikawa K. Laminectomy versus laminoplasty for cervical myelopathy: brief report. J Bone Joint Surg Br. 1988 Mar;70(2):325-6. PubMed PMID: 3346317.
10)

Nakama S, Nitanai K, Oohashi Y, Endo T, Hoshino Y. Cervical muscle strength after laminoplasty. J Orthop Sci. 2003;8(1):36-40. PubMed PMID: 12560884.
11)

Mori E, Ueta T, Maeda T, Yugué I, Kawano O, Shiba K. Effect of preservation of the C-6 spinous process and its paraspinal muscular attachment on the prevention of postoperative axial neck pain in C3-6 laminoplasty. J Neurosurg Spine. 2015 Mar;22(3):221-9. doi: 10.3171/2014.11.SPINE131153. Epub 2014 Dec 19. PubMed PMID: 25525962.
12)

Stamates MM, Cui MX, Roitberg BZ. Clinical Outcomes of Cervical Laminoplasty: Results at Two Years. Neurosurgery. 2017 Jun 1;80(6):934-941. doi: 10.1093/neuros/nyw058. PubMed PMID: 28329252.
13)

Sakaura H, Miwa T, Kuroda Y, Ohwada T. Surgical outcomes after laminoplasty for cervical spondylotic myelopathy in patients with renal dysfunction and/or aortic arch calcification. J Neurosurg Spine. 2016 Oct;25(4):444-447. PubMed PMID: 27231811.

Update: Chiari type 1 deformity

Chiari type 1 deformity is a hindbrain disorder associated with elongation of the cerebellar tonsils, which descend below the foramen magnum into the spinal canal.

The hindbrain is not malformed but deformed. Accordingly, “Chiari type 1 deformity,” not “Chiari type 1 malformation” is the correct term to characterize primary tonsillar herniation.

Defined as cerebellar tonsillar herniation ≥ 5 mm below the foramen magnum 1).

Classification

Chiari malformation Type 1.5 (CM 1.5) was defined as the association of Chiari malformation Type I (CM I) and brainstem herniation.

Although CM 1.5 patients presented with brainstem herniation and more severe tonsillar herniation, other clinical and imaging features and surgical outcomes were similar with CM I patients. Liu et al. think CM 1.5 is just a subtype of CM I, rather than a unique type of Chiari malformations 2).


Taylor et al. identifies two subtypes, crowded and spacious, that can be distinguished by MRI appearance without volumetric analysis. Earlier age at surgery and presence of syringomyelia are more common in the crowded subtype. The presence of the spacious subtype suggests that crowdedness alone cannot explain the pathogenesis of Chiari I malformation in many patients, supporting the need for further investigation 3).

Epidemiology

Chiari type 1 deformity is commonly seen in pediatric neurology, neuroradiology, and neurosurgery and may have various clinical presentations depending on patient age. In addition, Chiari type 1 deformity is increasingly found by neuroimaging studies as an incidental finding in asymptomatic children 4).

In the past, it was estimated that the condition occurs in about one in every 1,000 births. However, the increased use of diagnostic imaging has shown that CM may be much more common. Complicating this estimation is the fact that some children who are born with the condition may not show symptoms until adolescence or adulthood, if at all. CMs are more prevalent in certain groups, including people of Celtic descent.

A statistically significant (P = .03) female predominance of the malformation was observed, with a female: male ratio of approximately 3:2.

Associated skeletal anomalies were seen in 24% of patients.

Syringomyelia was detected in 40% of patients, most commonly between the C-4 and C-6 levels. Of the 25 patients who presented with spinal symptoms, 23 (92%) proved to have a syrinx at MR imaging. When the syrinx extended into the medulla (n = 3), however, brainstem symptoms predominated. Patients with objective brain stem or cerebellar syndrome had the largest mean tonsillar herniations. Patients with tonsillar herniations greater than 12 mm were invariably symptomatic, but approximately 30% of patients with tonsils herniating 5-10 mm below the foramen magnum were asymptomatic at MR imaging. “Incidental” Chiari I malformations are thus much more common than previously recognized, and careful clinical assessment remains the cornerstone for proper diagnosis and management 5).

Etiology

The innate bony dysontogenesis in patients with CMI contributes to tonsilar ectopia and exacerbates CSF flow obstruction. A pressure gradient that existed between syringomyelia(SM) and SAS supports the perivascular space theory that is used to explain SM formation. Our findings demonstrate that phase-contrast magnetic resonance imaging (PCMR) maybe a useful tool for predicting patient prognosis 6).

In adult CIM, most tonsillar herniations are asymmetrical and most syringomyelia is eccentrical. The dominant side of tonsillar herniation determines the side of syrinx deviation, which in turn determines the main side of clinical presentations and the convex side of scoliosis. The results suggest that the more the descended tonsil tilts to one side, the more the syrinx tilts to the same side 7).

Syndromic craniosynostosis

Chiari malformation Type I (CM-I) related to syndromic craniosynostosis in pediatric patients has been well-studied. The surgical management consists of cranial vault remodeling with or without posterior fossa decompression. There were also cases, in whom CM-I was diagnosed prior to the craniosynostosis in early childhood.

A 16-year-old boy who admitted with symptoms related to CM-I. With careful examination and further genetic investigations, a diagnosis of Crouzon syndrome was made, of which the patient and his family was unaware before. The patient underwent surgery for posterior fossa decompression and followed-up for Crouzon’s syndrome.

This is the only case report indicating a late adolescent diagnosis of Crouzon syndrome through clinical symptoms of an associated CM-I 8).

Familial clustering

A population-based genealogical resource with linked medical data was used to define the observed familial clustering of Chiari malformation Type I (CM-I). METHODS All patients with CM-I were identified from the 2 largest health care providers in Utah; those patients with linked genealogical data were used to test hypotheses regarding familial clustering. Relative risks (RRs) in first-, second-, and third-degree relatives were estimated using internal cohort-specific CM-I rates; the Genealogical Index of Familiality (GIF) test was used to test for an excess of relationships between all patients with CM-I compared with the expected distribution of relationships for matched control sets randomly selected from the resource. Pedigrees with significantly more patients with CM-I than expected (p < 0.05) based on internal rates were identified. RESULTS A total of 2871 patients with CM-I with at least 3 generations of genealogical data were identified. Significantly increased RRs were observed for first- and third-degree relatives (RR 4.54, p < 0.001, and RR 1.36, p < 0.001, respectively); the RR for second-degree relatives was elevated, but not significantly (RR 1.20, p = 0.13). Significant excess pairwise relatedness was observed among the patients with CM-I (p < 0.001), and borderline significant excess pairwise relatedness was observed when all relationships closer than first cousins were ignored (p = 0.051). Multiple extended high-risk CM-I pedigrees with closely and distantly related members were identified. CONCLUSIONS This population-based description of the familial clustering of 2871 patients with CM-I provided strong evidence for a genetic contribution to a predisposition to CM-I 9).

Pathophysiology

The pathophysiology of CMI is poorly understood and it remains unknown how ICP alterations relate to symptoms and radiological findings.

There is some evidence of impaired intracranial compliance as an important pathophysiological mechanism 10).

Magnetic resonance imaging measurement of transcranial CSF flow and blood flow may lead to a better understanding of the pathophysiology of Chiari malformations and may prove to be an important diagnostic tool for guiding for the treatment of patients with Chiari I malformation 11).

The pathogenesis of a Chiari I malformation of the cerebellar tonsils is grouped into 4 general mechanisms. 12).

It appears that the pathogenesis of Chiari malformation with or without associated basilar invagination and/or syringomyelia is primarily related to atlantoaxial instability. The data suggest that the surgical treatment in these cases should be directed toward atlantoaxial stabilization and segmental arthrodesis. Except in cases in which there is assimilation of the atlas, inclusion of the occipital bone is neither indicated nor provides optimum stability. Foramen magnum decompression is not necessary and may be counter-effective in the long run 13). It occurs in children and adults. Clinical symptoms mainly develop from alterations in CSF flow at the foramen magnum and the common subsequent development of syringomyelia.


Patients with Chiari malformation type 1 (CMI) often present with elevated pulsatile and static intracranial pressure (ICP).

Several lines of evidence suggest common pathophysiological mechanisms in Chiari malformation Type I (CMI) and idiopathic intracranial hypertension (IIH). It has been hypothesized that tonsillar ectopy, a typical finding in CMI, is the result of elevated intracranial pressure (ICP) combined with a developmentally small posterior cranial fossa (PCF).

The study of Frič and Eide showed comparable and elevated pulsatile intracranial pressure, indicative of impaired intracranial compliance, in both CMI and IIH cohorts, while static ICP was higher in the IIH cohort. The data did not support the hypothesis that reduced PCFV combined with increased ICP causes tonsillar ectopy in CMI. Even though impaired intracranial compliance seems to be a common pathophysiological mechanism behind both conditions, the mechanisms explaining the different clinical and radiological presentations of CMI and IIH remain undefined14).

Natural history

Chiari malformation Type I was incidentally detected on MR images in 11 of 22 patients. The remaining 11 patients had minimal clinical signs at presentation that were not regarded as necessitating immediate surgical treatment. Seventeen patients (77.3%) showed progressive improvement in their symptoms or remained asymptomatic at the last follow-up whereas 5 patients (22.7%) experienced worsening, which was mild in 2 cases and required surgical correction in the remaining 3 cases. On MR imaging a mild reduction in tonsillar herniation was appreciated in 4 patients (18.18%), with complete spontaneous resolution in 1 of these. In 16 patients, tonsillar herniation remained stable during follow-up.

Data confirm the common impression that in both asymptomatic and slightly symptomatic patients with CM-I, a conservative approach to treatment should be adopted with periodic clinical and radiological examinations 15).

Clinical Features

Although the most common presentation is occipital headache, the association of audio-vestibular symptoms is not rare.

The headache is commonly aggravated by Valsalva and sensory and motor deficits.

In a series of 71 patients, pain was the commonest symptom (69% of patients); other symptoms included weakness (56%), numbness (52%), and unsteadiness (40%). The presenting physical signs consisted of a foramen magnum syndrome (22%), central cord syndrome (65%), or a cerebellar syndrome (11%) 16).

Audio-vestibular manifestations

The appearance of audio-vestibular manifestations in CM-I makes it common to refer these patients to neurotologists. Unsteadiness, vertiginous syndromes and sensorineural hearing loss are frequent. Nystagmus, especially horizontal and down-beating, is not rare. It is important for neurotologists to familiarise themselves with CM-I symptoms to be able to consider it in differential diagnosis 17).


Feinberg et al present a case of Chiari malformation manifesting as isolated trismus, describe the typical symptoms associated with Chiari malformation, and discuss the potential anatomical causes for this unique presentation. A 3-year-old boy presented with inability to open his jaw for 6 weeks with associated significant weight loss. The results of medical and radiological evaluation were negative except for Chiari malformation type 1 with cerebellar tonsils 12 mm below the level of the foramen magnum. The patient underwent Chiari decompression surgery. Postoperatively, his ability to open his mouth was significantly improved, allowing resumption of a regular diet. Postoperative MRI revealed almost complete resolution of the syringobulbia. To the best of the authors’ knowledge, this is the first reported case of isolated trismus from Chiari malformation with syringobulbia 18).

Diagnosis

Along with tonsillar herniation, imaging studies have documented additional abnormalities, including smaller and overcrowded posterior cranial fossa 19) 20) 21) 22) 23).

MRI Findings After Surgery for Chiari Malformation Type I is important when evaluating postoperative changes 24).


Sagittal MRI overestimates the degree of tonsillar ectopia. Misdiagnosis may occur if sagittal imaging alone is used. The cerebellar tonsils are paramedian structures, and this should be kept in mind when interpreting midline sagittal MRI.

Treatment

An accurate and reliable selection of patients based on clinical and neuroimaging findings is paramount for the success of neurosurgical treatment25).

see Posterior fossa decompresion for Chiari type 1 deformity.

Outcome

Efforts to guide preoperative counseling and improve outcomes research are impeded by reliance on small, single-center studies.

Approximately 1 in 8 pediatric CM-I patients experienced a surgical complication, whereas medical complications were rare. Although complex chronic conditions (CCC) were common in pediatric CM-I patients, only hydrocephalus was independently associated with increased risk of surgical events. These results may inform patient counseling and guide future research efforts 26).

CM-I in children is not a radiologically static entity but rather is a dynamic one. Radiological changes were seen throughout the 7 years of follow-up. A reduction in tonsillar herniation was substantially more common than an increase. Radiological changes did not correlate with neurological examination finding changes, symptom development, or the need for future surgery. Follow-up imaging of asymptomatic children with CM-I did not alter treatment for any patient. It would be reasonable to follow these children with clinical examinations but without regular surveillance MRI 27).

Outcome assessment for the management of Chiari malformation type 1 is difficult because of the lack of a reliable and specific surgical outcome assessment scale. Such a scale could reliably correlate postoperative outcomes with preoperative symptoms.

Chicago Chiari Outcome Scale (CCOS)

Outcome is poor in approximately 3 in 10 patients 28).

The degree of tonsillar herniation has not been a reliable predictor of either symptom severity 29) or surgical outcome 30).

Arnautovic et al. identified 145 operative series of patients with CM-I, primarily from the United States and Europe, and divided patient ages into 1 of 3 categories: adult (> 18 years of age; 27% of the cases), pediatric (≤ 18 years of age; 30%), or unknown (43%). Most series (76%) were published in the previous 21 years. The median number of patients in the series was 31. The mean duration of the studies was 10 years, and the mean follow-up time was 43 months. The peak ages of presentation in the pediatric studies were 8 years, followed by 9 years, and in the adult series, 41 years, followed by 46 years. The incidence of syringomyelia was 65%. Most of the studies (99%) reported the use of posterior fossa/foramen magnum decompression. In 92%, the dura was opened, and in 65% of these cases, the arachnoid was opened and dissected; tonsillar resection was performed in 27% of these patients. Postoperatively, syringomyelia improved or resolved in 78% of the patients. Most series (80%) reported postoperative neurological outcomes as follows: 75% improved, 17% showed no change, and 9% experienced worsening. Postoperative headaches improved or resolved in 81% of the patients, with a statistical difference in favor of the pediatric series. Postoperative complications were reported for 41% of the series, most commonly with CSF leak, pseudomeningocele, aseptic meningitis, wound infection, meningitis, and neurological deficit, with a mean complication rate of 4.5%. Complications were reported for 37% of pediatric, 20% of adult, and 43% of combined series. Mortality was reported for 11% of the series. No difference in mortality rates was seen between the pediatric and adult series 31).

Complications

Patients treated for Chiari I malformation (CM-I) with posterior fossa decompression (PFD) may occasionally and unpredictably develop postoperative hydrocephalus. The clinical risk factors predictive of this type of Chiari-related hydrocephalus (CRH) are unknown.

Younger patients, those with extensive intraoperative blood loss, and those found during surgery to have a fourth ventricular web were at higher risk for the development of CRH. Clinicians should be alert to evidence of CRH in this patient population after PFD surgery 32).

Sports

There is currently no consensus on the safety of sports participation for patients with Chiari I malformation (CM-I).

A prospective survey was administered to 503 CM-I patients at 2 sites over a 46-month period. Data were gathered on imaging characteristics, treatment, sports participation, and any sport-related injuries. Additionally, 81 patients completed at least 1 subsequent survey following their initial entry into the registry and were included in a prospective group, with a mean prospective follow-up period of 11 months.

Of the 503 CM-I patients, 328 participated in sports for a cumulative duration of 4641 seasons; 205 of these patients participated in contact sports. There were no serious or catastrophic neurological injuries. One patient had temporary extremity paresthesias that resolved within hours, and this was not definitely considered to be related to the CM-I. In the prospective cohort, there were no permanent neurological injuries.

No permanent or catastrophic neurological injuries were observed in CM-I patients participating in athletic activities. The authors believe that the risk of such injuries is low and that, in most cases, sports participation by children with CM-I is safe 33).

Case series

2017

Brock et al., analyzed prospectively 49 patients with CM operated at the Hospital das Clinicas, College of Medicine, University of São Paulo. Patients underwent decompressive surgery with or without opening of the duramater after intraoperative ultrasonography measuring flow rate. A value of 3cm/s was considered a cut-off. Quality of life before and after surgery and the improvement of neck pain and headache were evaluated.

Among 49 patients enrolled, 36 patients (73%) had CSF flow above 3 cm/s and did not undergo duraplasty. In 13 (27%) patients with initial flow <3 cm/s, a dural opening was performed together with duraplasty. All patients improved comparing pre and post operative scores and all clinical parameters evaluated did not differ between both surgical groups. Patients submitted to bone decompression alone had fewer complication rate.

Intraoperative USG with measurement of CSF allows the proper selection of patients with CM that can have a less invasive surgery with bone decompression without duraplasty 34).

2015

A retrospective cohort study was performed for patients 0-18 years of age who underwent surgical correction for Chiari Type I malformation with syrinx between 1995 and 2013. Basic demographic information was collected as well as data for preoperative symptoms, prior surgical history, perioperative characteristics, and postsurgical outcomes. Descriptive statistics were performed in addition to bivariate analyses. Candidate predictor variables were identified based on an association with tonsillar cautery with p < 0.10. Forward stepwise likelihood ratio was used to select candidate predictors in a binary logistic regression model (Pin = 0.05, Pout = 0.10) most strongly associated with the outcome. RESULTS A total of 171 patients with Chiari Type I malformation with syrinx were identified, and 43 underwent tonsillar cautery. Patients who underwent tonsillar cautery had 6.11 times greater odds of improvement in their syrinx (95% CI 2.57-14.49, p < 0.001). There was no effect of tonsillar cautery on increased perioperative complications as well as the need for repeat decompressions. CONCLUSIONS Tonsillar cautery is safe and effective in the treatment of Chiari Type I malformation with syrinx and may decrease time to syrinx resolution after cervicomedullary decompression. Tonsillar cautery does not increase postoperative complications in pediatric Chiari Type I malformation patients 35)


156 consecutive pediatric patients in whom the senior authors performed PFD without dural opening from 2003 to 2013. Patient demographics, clinical symptoms and signs, radiographic findings, intraoperative ultrasound results, and neuromonitoring findings were reviewed. Univariate and multivariate regression analyses were performed to determine risk factors for recurrence of symptoms and the need for reoperation. RESULTS Over 90% of patients had a good clinical outcome, with improvement or resolution of their symptoms at last follow-up (mean 32 months). There were no major complications. The mean length of hospital stay was 2.0 days. In a multivariate regression model, partial C-2 laminectomy was an independent risk factor associated with reoperation (p = 0.037). Motor weakness on presentation was also associated with reoperation but only with trend-level significance (p = 0.075). No patient with < 8 mm of tonsillar herniation required reoperation.

The vast majority (> 90%) of children with symptomatic CM-I will have improvement or resolution of symptoms after a PFD without dural opening. A non-dural opening approach avoids major complications. While no patient with tonsillar herniation < 8 mm required reoperation, children with tonsillar herniation at or below C-2 have a higher risk for failure when this approach is used 36).


Thirty-nine cases of CM-1 with and without syringomyelia (SM) were included. There were 18 patients in the nonduraplasty and 21 in the duraplasty group. Syringomyelia, tonsillar herniation (TH), preoperative symptom duration, and postoperative SM size were compared.

No significant difference was found between improvement in the duraplasty group (81%) and the non-duraplasty group (61.1%). In cases whose symptom duration was 0-36 months, improvement in the duraplasty group (93%) was significantly better than in the nonduraplasty group (50%) (p < 0.01). The rate of syrinx regression was 92.3% in the duraplasty group and 12.5% in the non-duraplasty group (p < 0.05). In cases with SM, the improvement was 21.4% in the non-duraplasty group compared to 78.6% in the duraplasty group (p=0.056). In cases with TH greater than 10 mm, the improvement was 66.7% in the non-duraplasty group, whereas all six cases (100%) in the duraplasty group had improved.

In SM associated cases, cases with TH greater than 10 mm, and whose symptom duration is less than 36 months, duraplasty is a more reliable choice despite a slightly higher rate of complications 37).

2014

In 21 patients, 12 cases had osteo-compression on the cerebellar hemisphere, 18 cases had thickened adhered fabric ring that stretched from arachnoid membrane to cerebellar hemisphere, and 15 cases with syringomyelia. The patients were followed up for 6 months to 3 years after the surgery. All patients showed a remarkable recovery of syringomyelia. There were no morbidity or death related to the surgery. Most of ACM-1 patients, the osteo- and membrane compression on cerebellar hemisphere and tonsil were observed during the operation. Therefore, decompression of foramen magnum and posterior craniocervical combined with the removal of cerebellomedullary fissure arachnoid membrane and placement of an artificial dural graft should be considered as a comprehensive option of minimally invasive surgery and rational and radical treatment of ACM-1. Our experience showed that, by using our procedure, shunting becomes no longer necessary in the treatment of ACM-1-associated syringomyelia 38).

1992

Of the 25 patients who presented with spinal symptoms, 23 (92%) proved to have a syrinx at MR imaging. When the syrinx extended into the medulla (n = 3), however, brain stem symptoms predominated. Patients with objective brain stem or cerebellar signs had the largest mean tonsillar herniations. Patients with tonsillar herniations greater than 12 mm were invariably symptomatic, but approximately 30% of patients with tonsils herniating 5-10 mm below the foramen magnum were asymptomatic at MR imaging. “Incidental” Chiari I malformations are thus much more common than previously recognized, and careful clinical assessment remains the cornerstone for proper diagnosis and management 39).

1983

In a series of 71 patients, pain was the commonest symptom (69% of patients); other symptoms included weakness (56%), numbness (52%), and unsteadiness (40%). The presenting physical signs consisted of a foramen magnum compression syndrome (22%), central cord syndrome (65%), or a cerebellar syndrome (11%). Myelography was performed in 69 patients, and was the most useful investigation. Only 23% of plain radiographs were abnormal. In addition to tonsillar descent, the operative findings included arachnoid adhesions (41%) and syringomyelia (32%). All patients underwent suboccipital craniectomy and C1-3 laminectomy. Respiratory depression was the most frequent postoperative complication (14%), and one patient died from sleep apnea. Early postoperative improvement of both symptoms (82%) and signs (70%) was followed by later relapse in 21% of patients, showing an initial benefit following surgery. None of the patients with a cerebellar syndrome deteriorated, whereas 56% of patients with evidence of foramen magnum compression and 66% of those with a central cord syndrome maintained their initial improvement. The authors conclude that posterior fossa decompression appears to benefit some patients, although a significant proportion might be expected to relapse within 2 to 3 years after operation, depending upon the presenting syndrome 40).

Case reports

2007

A 13-year-old obese boy with a 3-week history of headaches, neck pain, torticollis and progressive visual deterioration was admitted. Bilateral chronic papilledema and decrease in visual acuity were found in the presence of a previously diagnosed CMI.

Intracranial pressure monitoring demonstrating increased pressure levels was followed by a suboccipital decompression, C1 laminectomy and duroplasty. Post-operatively, the boy improved markedly, the 6 months follow-up opthalmological examination demonstrated resolution of papilloedema, but consecutive bi-lateral optic nerve atrophy.

IH with progressive visual deterioration represents one of the varying clinical presentations of CMI and may be classified as a secondary form of idiopathic intracranial hypertension (IH). Neuro-ophthalmological examination in all patients with CMI is recommended to identify the real incidence of this presentation. Altered CSF dynamics, venous hypertension and obesity as co-factors may be causative pathophysiologic factors 41).

Books

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International Gamma Knife Research Foundation

Upcoming Meetings

ASSFN 2016

IGKRF Biennial Scientific Session
University of Pennsylvania
Philadelphia, Pa.
June 23, 2017
Meeting Brochure

http://www.igkrf.org/

The International Gamma Knife Research Foundation consists of academic and clinical centers of excellence where brain Stereotactic Radiosurgery is performed using the Leksell Gamma Knife. All participating centers have a track record of outcomes research and participation in clinical trials.

The primary goal of the IGKRF is to facilitate retrospective and prospective clinical trials and outcomes analysis that evaluate the role of Gamma Knife radiosurgery in a wide spectrum of clinical indications.

Because individual centers may evaluate only a small number of patients with rare conditions, pooling of information is critical to evaluate and to improve outcomes. Each center has a professional team consisting of one or more neurological surgeons, radiation oncologists, and medical physicists. Participation is by invitation of the Board of Directors. ​ The IGKRF is a non-profit scientific, educational, and research entity incorporated in the state of Pennyslvania.​

Case series

2017

Ding et al. evaluated and pooled AVM radiosurgery data from 8 institutions participating in the International Gamma Knife Research Foundation. Patients with unruptured AVMs and ≥12 mo of follow-up were included in the study cohort. Favorable outcome was defined as AVM obliteration, no postradiosurgical hemorrhage, and no permanently symptomatic radiation-induced changes.

The unruptured AVM cohort comprised 938 patients with a median age of 35 yr. The median nidus volume was 2.4 cm 3 , 71% of AVMs were located in eloquent brain areas, and the Spetzler-Martin grade was III or higher in 57%. The median radiosurgical margin dose was 21 Gy and follow-up was 71 mo. AVM obliteration was achieved in 65%. The annual postradiosurgery hemorrhage rate was 1.4%. Symptomatic and permanent radiation-induced changes occurred in 9% and 3%, respectively. Favorable outcome was achieved in 61%. In the multivariate logistic regression analysis, smaller AVM maximum diameter ( P = .001), the absence of AVM-associated arterial aneurysms ( P = .001), and higher margin dose ( P = .002) were found to be independent predictors of a favorable outcome. A margin dose ≥ 20 Gy yielded a significantly higher rate of favorable outcome (70% vs 36%; P < .001).

Radiosurgery affords an acceptable risk to benefit profile for patients harboring unruptured AVMs. These findings justify further prospective studies comparing radiosurgical intervention to conservative management for unruptured AVMs 1).

2016

Data from a cohort of 2236 patients undergoing GKRS for cerebral AVMs were compiled from the International Gamma Knife Research Foundation. Favorable outcome was defined as AVM obliteration and no posttreatment hemorrhage or permanent symptomatic radiation-induced complications. Patient and AVM characteristics were assessed to determine predictors of outcome, and commonly used grading scales were assessed.

The mean maximum AVM diameter was 2.3 cm, with a mean volume of 4.3 cm3. A mean margin dose of 20.5 Gy was delivered. Mean follow-up was 7 years (range 1-20 years). Overall obliteration was 64.7%. Post-GRKS hemorrhage occurred in 165 patients (annual risk 1.1%). Radiation-induced imaging changes occurred in 29.2%; 9.7% were symptomatic, and 2.7% had permanent deficits. Favorable outcome was achieved in 60.3% of patients. Patients with prior nidal embolization (OR 2.1, p < 0.001), prior AVM hemorrhage (OR 1.3, p = 0.007), eloquent location (OR 1.3, p = 0.029), higher volume (OR 1.01, p < 0.001), lower margin dose (OR 0.9, p < 0.001), and more isocenters (OR 1.1, p = 0.011) were more likely to have unfavorable outcomes in multivariate analysis. The Spetzler-Martin grade and radiosurgery-based AVM score predicted outcome, but the Virginia Radiosurgery AVM Scale provided the best assessment.

GKRS for cerebral AVMs achieves obliteration and avoids permanent complications in the majority of patients. Patient, AVM, and treatment parameters can be used to predict long-term outcomes following radiosurgery 2). ​

1)

Ding D, Starke RM, Kano H, Lee JYK, Mathieu D, Pierce J, Huang P, Missios S, Feliciano C, Rodriguez-Mercado R, Almodovar L, Grills IS, Silva D, Abbassy M, Kondziolka D, Barnett GH, Lunsford LD, Sheehan JP. Radiosurgery for Unruptured Brain Arteriovenous Malformations: An International Multicenter Retrospective Cohort Study. Neurosurgery. 2017 Jun 1;80(6):888-898. doi: 10.1093/neuros/nyx181. PubMed PMID: 28431024.
2)

Starke RM, Kano H, Ding D, Lee JY, Mathieu D, Whitesell J, Pierce JT, Huang PP, Kondziolka D, Yen CP, Feliciano C, Rodgriguez-Mercado R, Almodovar L, Pieper DR, Grills IS, Silva D, Abbassy M, Missios S, Barnett GH, Lunsford LD, Sheehan JP. Stereotactic radiosurgery for cerebral arteriovenous malformations: evaluation of long-term outcomes in a multicenter cohort. J Neurosurg. 2016 Mar 4:1-9. [Epub ahead of print] PubMed PMID: 26943847.