Ray Chu

Spinal manifestations of spontaneous intracranial hypotension.

OBJECT The goal of the study was to elucidate the spinal manifestations of spontaneous intracranial hypotension. METHODS The authors reviewed the medical records and imaging studies of 338 consecutive patients with spontaneous intracranial hypotension who were evaluated at their institution between 2001 and 2010. RESULTS Twenty patients (6%; mean age 35.8 [range 16 to 60 years]; 5 males and 15 females) had convincing signs or symptoms referable to the spinal cord or spinal nerve roots. The spinal manifestations consisted of radiculopathy in 11 patients (unilateral in 8 and bilateral in 3), myelopathy in 8 patients, and bibrachial amyotrophy in 1 patient. The cervical spine was involved in 12 patients, the thoracic spine in 5, and the lumbosacral spine in 3. The spinal symptoms were positional in only 3 patients. The spinal manifestations occurred around the time of the headache onset in 16 patients, and months to years after the positional headache had resolved in 4 patients. A large extrathecal CSF collection causing compression of the spinal cord or nerve root was responsible for the spinal manifestations in the majority of patients. Treatment of the spinal CSF leak resulted in resolution of the spinal manifestations along with the headache, except for those in the patient with bibrachial amyotrophy. CONCLUSIONS Spinal manifestations are uncommon in cases of spontaneous intracranial hypotension, occurring in about 6% of patients, but myelopathy and radiculopathy involving all spinal segments do occur. Unlike the headache, the spinal manifestations usually are not positional and are caused by mass effect from an extradural CSF collection.

Comparative analysis of outcomes following craniotomy and expanded endoscopic endonasal transsphenoidal resection of craniopharyngioma and related tumors: a single-institution study

OBJECTIVE Craniopharyngiomas and similar midline suprasellar tumors have traditionally been resected via transcranial approaches. More recently, expanded endoscopic endonasal transsphenoidal approaches have gained interest. Surgeons have advocated for both approaches, and at present there is no consensus whether one approach is superior to the other. The authors therefore compared surgical outcomes between craniotomy and endoscopic endonasal transsphenoidal surgery (EETS) for suprasellar tumors treated at their institution. METHODS A retrospective review of patients undergoing resection of suprasellar lesions at Cedars-Sinai Medical Center between 2000 and 2013 was performed. Patients harboring suspected craniopharyngioma were selected for extensive review. Other pathologies or predominantly intrasellar masses were excluded. Cases were separated into 2 groups, based on the surgical approach taken. One group underwent EETS and the other cohort underwent craniotomy. Patient demographic data, presenting symptoms, and previous therapies were tabulated. Preoperative and postoperative tumor volume was calculated for each case based on MRI. Student t-test and the chi-square test were used to evaluate differences in patient demographics, tumor characteristics, and outcomes between the 2 cohorts. To assess for selection bias, 3 neurosurgeons who did not perform the surgeries reviewed the preoperative imaging studies and clinical data for each patient in blinded fashion and indicated his/her preferred approach. These data were subject to concordance analysis using Cohens kappa test to determine if factors other than surgeon preference influenced the choice of surgical approach. RESULTS Complete data were available for 53 surgeries; 19 cases were treated via EETS, and 34 were treated via craniotomy. Patient demographic data, preoperative symptoms, and tumor characteristics were similar between the 2 cohorts, except that fewer operations for recurrent tumor were observed in the craniotomy cohort compared with EETS (17.6% vs 42.1%, p = 0.05). The extent of resection was similar between the 2 groups (85.6% EETS vs 90.7% craniotomy, p = 0.77). An increased rate of cranial nerve injury was noted in the craniotomy group (0% EETS vs 23.5% craniotomy, p = 0.04). Postoperative CSF leak rate was higher in the EETS group (26.3% EETS vs 0% craniotomy, p = 0.004). The progression-free survival curves (log-rank p = 0.99) and recurrence rates (21.1% EETS vs 23.5% craniotomy, p = 1.00) were similar between the 2 groups. Concordance analysis of cases reviewed by 3 neurosurgeons indicated that individual surgeon preference was the only factor that determined surgical approach (kappa coefficient -0.039, p = 0.762) CONCLUSIONS: Surgical outcomes were similar for tumors resected via craniotomy or EETS, except that more CSF leaks occurred in the EETS cohort, whereas more neurological injuries occurred in the craniotomy cohort. Surgical approach appears to mostly reflect surgeon preference rather than specific tumor characteristics. These data support the view that EETS is a viable alternative to craniotomy, providing a similar extent of resection with less neurological injury.

Association of Intracranial Aneurysms with Meningiomas, Pituitary Adenomas, and Gliomas: Review of Possible Interrelationships

Asymptomatic intracranial abnormalities are increasingly becoming a focus of attention with the utilization of high-resolution imaging. The concurrence of tumor and aneurysm has been described, largely, by case reports and single-surgeon experiences. Recent papers have outlined the ethics of incidental findings and possible treatment algorithms. Incidental finding of an aneurysm occurs most commonly in patients with meningiomas, pituitary adenomas, and gliomas. Such an association may explain the mechanisms of aneurysm formation, growth, and rupture in acromegalic patients; however, insufficient data are available to link aneurysm with either glioma or meningioma.

False localizing sign of cervico-thoracic CSF leak in spontaneous intracranial hypotension

Objective: Spontaneous spinal CSF leaks are an important cause of new-onset headaches. Such leaks are reported to be particularly common at the cervico-thoracic junction. The authors undertook a study to determine the significance of these cervico-thoracic CSF leaks. Methods: The patient population consisted of a consecutive group of 13 patients who underwent surgery for CSF leak repair based on CT myelography showing CSF extravasation at the cervico-thoracic junction but without any evidence of an underlying structural lesion. Results: The mean age of the 9 women and 4 men was 41.2 years. Extensive extrathecal longitudinal CSF collections were demonstrated in 11 patients. At surgery, small leaking arachnoid cysts were found in 2 patients. In the remaining 11 patients, no clear source of CSF leakage could be identified at surgery. Resolution of symptoms was achieved in both patients with leaking arachnoid cysts, but in only 3 of the 11 patients with negative intraoperative findings. Postoperative spinal imaging was performed in 9 of the 11 patients with negative intraoperative findings and showed persistence of the longitudinal intraspinal extradural CSF. Further imaging revealed the site of the CSF leak to be ventral to the thoracic spinal cord. Five of these patients underwent microsurgical repair of the ventral CSF leak with resolution of symptoms in all 5 patients. Conclusions: Cervico-thoracic extravasation of dye on myelography does not necessarily indicate the site of the CSF leak. Treatment directed at this site should not be expected to have a high probability of sustained improvement of symptoms.

Incidental Finding of Tumor While Investigating Subarachnoid Hemorrhage: Ethical Considerations and Practical Strategies

High-resolution neuroimaging modalities are used often in studies involving healthy volunteers. Subsequently, a significant increase in the incidental discovery of asymptomatic intracranial abnormalities raised the important ethical issues of when follow-up and treatment may be necessary. We examined the literature to establish a practical set of criteria for approaching incidental findings. Our objective is to develop an algorithm for when follow-up may be important and to provide recommendations that would increase the likelihood of follow-up. A systematic literature search was performed using the PubMed and MEDLINE databases to identify articles describing brain tumors and intracranial aneurysms. The treatment algorithm we present suggests that incidental intracranial masses suspicious for glioma should be biopsied or resected, while other masses are to be followed with serial imaging based on the expected growth pattern. Lack of follow-up can result in adverse outcomes that can be mitigated by using technology to facilitate communication and improve follow-up care. The importance of training physicians to be good communicators is also stressed. New technology including automated telephone systems, texting and email will improve access to patients and hopefully encourage compliance and follow-up.

Intraoperative optical biopsy for brain tumors using spectro-lifetime properties of intrinsic fluorophores

We have developed and tested a system for real-time intra-operative optical identification and classification of brain tissues using time-resolved fluorescence spectroscopy (TRFS). A supervised learning algorithm using linear discriminant analysis (LDA) employing selected intrinsic fluorescence decay temporal points in 6 spectral bands was employed to maximize statistical significance difference between training groups. The linear discriminant analysis on in vivo human tissues obtained by TRFS measurements (N = 35) were validated by histopathologic analysis and neuronavigation correlation to pre-operative MRI images. These results demonstrate that TRFS can differentiate between normal cortex, white matter and glioma.