Alan M. Scarrow

Radiosurgery for childhood intracranial arteriovenous malformations.

OBJECTIVEThe optimal management of intracranial arteriovenous malformations (AVMs) in children remains controversial. Children with intracranial AVMs present a special challenge in therapeutic decision-making because of the early recognition of their future life-long risks of hemorrhage if they are treated conservatively. The goals of radiosurgery are to achieve complete AVM obliteration and to preserve neurological function. We present long-term outcomes for a series of children treated using radiosurgery. METHODSThe findings for 53 consecutive children who underwent at least 36 months of imaging follow-up monitoring after radiosurgery were reviewed. The median age at the time of treatment was 12 years (range, 2–17 yr). Thirty-one children (58%) presented after their first intracranial hemorrhaging episodes, two (4%) after their second hemorrhaging episodes, and one (2%) after five hemorrhaging episodes. Nineteen children (36%) presented with unruptured AVMs, and a total of 25 children (47%) exhibited neurological deficits. AVMs were graded as Spetzler-Martin Grade I (2%), Grade II (23%), Grade III (36%), Grade IV (9%), or Grade VI (30%). The median AVM volume was 1.7 ml (range, 0.11–10.2 ml). The median marginal dose was 20 Gy (range, 15–25 Gy). RESULTSResults were stratified according to AVM volumes (Group 1, ≤3 ml; Group 2, >3 ml to ≤10 ml; Group 3, >10 ml). Twenty-eight patients (80%) in Group 1 and 11 (64.7%) in Group 2 achieved complete obliteration. The only patient in Group 3 did not achieve obliteration. Complications included brainstem edema (n = 1) and transient pulmonary edema (n = 1). Four patients experienced hemorrhaging episodes, 30, 40, 84, and 96 months after radiosurgery. Multivariate logistic regression analysis demonstrated that only volume was significantly correlated with obliteration rates (P = 0.0109). CONCLUSIONRadiosurgery is safe and efficacious for selected children with AVMs. The obliteration rates and the attendant low morbidity rates suggest a primary role for stereotactic radiosurgery for pediatric AVMs.

Recurrent trigeminal neuralgia attributable to veins after microvascular decompression.

OBJECTIVE To demonstrate the cause of and optimal treatment for recurrent trigeminal neuralgia (TN) in cases where veins were observed to be the offending vessels during the initial microvascular decompression (MVD) procedure. METHODS An electronic search of patient records from 1988 to 1998 revealed that 393 patients were treated with MVD for TN caused by veins. The pain recurred in 122 patients (31.0%). Thirty-two (26.2%) of these patients underwent reoperations. Clinical presentations, recurrence intervals, surgical findings, and clinical outcomes were analyzed. RESULTS Analysis of 32 consecutive cases of recurrent TN initially attributable to veins revealed a female predominance (female/male = 26:5), with one female patient exhibiting bilateral TN caused by venous compression. Patient ages ranged from 15 to 80 years, with a prevalence in the seventh decade. The V2 distribution of the face was involved more frequently than other divisions. For 24 patients (75%), recurrence occurred within 1 year after the initial operation. At the time of the second MVD procedure, development of new veins around the nerve root was observed in 28 cases (87.5%). After successful subsequent MVD procedures, the pain was improved in 81.3% of the cases. CONCLUSION The recurrence rate for TN attributable to veins is high. If pain recurs, it is likely to recur within 1 year after the initial operation. The most common cause of recurrence is the development and regrowth of new veins. Even fine new veins may cause pain recurrence; these veins may be located beneath the felt near the root entry zone or distally, near Meckels cave. Because of the variable locations of vein recurrence, every effort must be made to identify recollateralized veins. Given the high rate of pain relief after a second operation, MVD remains the optimal treatment for the recurrence of TN attributable to vein regrowth.

Microvascular decompression in the treatment of hypertension: review and update.

BACKGROUND Neurogenic hypertension in association with vascular compression of the left rostral ventrolateral medulla has been documented. A recent group of these clinical reports has raised great interest in decompression of this area of the brainstem as a definitive therapy for essential hypertension. METHODS To further clarify the mechanism by which decompression of the left rostral ventrolateral medulla relieves neurogenic hypertension, we describe in detail the basic science, animal models, human studies, and most recent clinical trials regarding surgical decompression of this area. CONCLUSION Multi-disciplinary evidence supports the hypothesis that a sub-population of hypertensive patients achieve significant relief of their hypertension after microvascular decompression. A multi-institutional, prospective, randomized study is necessary to determine the efficacy of microvascular decompression for neurogenic hypertension.

Outcome analysis of endoscopic III ventriculostomy.

Abstract A retrospective chart review was performed on 54 patients who had undergone endoscopic III ventriculostomy (E3V) in the past 6 years. Patient charts were reviewed to establish age at the time of operation, sex, preoperative diagnosis, preoperative shunt procedures, success or failure of the E3V, duration of success, and complications. Success of an E3V was determined by the resolution of preoperative symptoms and avoidance of a CSF shunt. The most recent clinic visit with adequate documentation of signs and symptoms of hydrocephalus was used as the last date of follow-up. The overall success rate was 74%. Children over the age of 3 years with an acquired CSF obstruction had a significantly greater probability of successful treatment (P=0.05). Younger children, especially those with hydrocephalus attributable to obstruction of the arachnoid villi, as in intraventricular hemorrhage (IVH), were less likely to benefit from E3V.

Cervical spine evaluation in obtunded or comatose pediatric trauma patients: A pilot study.

A uniformly accepted protocol for evaluation and clearance of the cervical spine of pediatric trauma patients with altered mental status does not currently exist. We sought to detect cervical spine injuries in this group with minimal risk. Patients were evaluated with standard three-view cervical spine radiographs and CT when necessary. Those patients without radiographic abnormality and altered mental status underwent flexion-extension of the cervical spine using fluoroscopy with somatosensory evoked potential (SSEP) monitoring. Those with abnormal movement by fluoroscopy or changes in SSEP underwent MRI. Fifteen patients were evaluated with this protocol. Two patients had movement on flexion-extension of the cervical spine and 5 had SSEP changes. Three patients had an MRI with only 1 showing injury. Five patients had residual hemiparesis. Evaluation of the cervical spine in obtunded or comatose pediatric trauma patients can be done safely with flexion-extension under fluoroscopy and SSEP monitoring. Further prospective studies are required to determine the efficacy of SSEP monitoring for cervical spine clearance in this select population.

Epidermoid cyst of the thoracic spine: case history

Epidermoid cysts of the spinal cord are very rare tumors. We report a 31 year-old female who presented with a 5 months history of progressive lower extremity weakness and spasticity. Magnetic resonance imaging of the thoracic spine revealed a 2 cm intradural, extramedullary mass at the T4-5 level. A T4 and T5 osteoplastic laminotomy with complete removal of the intradural mass was performed. Intraoperative and final histological examination revealed an epidermoid cyst. Epidermoid cysts must be a consideration for intradural, extramedullary lesions of the spinal cord. Complete surgical resection offers the patient an opportunity for good neurologic outcome.

Remote Effects of Acute Ischemic Stroke: A Xenon CT Cerebral Blood Flow Study

Objective: The purpose of this study was to verify transhemispheric diaschisis in the early hours after an ischemic event. Methods: XeCT cerebral blood flow (CBF) studies within 8 h of stroke were studied in 23 patients. Mean CBF was evaluated in the ischemic area, contralateral hemisphere and ipsilateral cerebellum. Results: A severe CBF reduction was found in the ischemic area (mean 9 ± 3 ml/100 g/min). The mean CBF in the unaffected hemisphere (33 ± 10 ml/100 g/min) was 35% less compared to the normal mean value. CBF was decreased in the cerebellum ipsilateral to the stroke (mean 31 ± 12 ml/100 g/min) suggesting a blood flow depression of the whole brain. Conclusions: During the initial hours of cerebral ischemia, the asymptomatic hemisphere demonstrated CBF depression that was part of the global flow reduction.

Thyroid carcinoma with isolated spinal metastasis: case history and review of the literature.

An unusual case of metastatic follicular thyroid cancer presenting with symptoms of a radiculopathy at C6 is presented. The patient underwent a laminectomy and removal of tumor with resolution of his symptoms. He was found to have a well differentiated follicular thyroid carcinoma and subsequently had total thyroidectomy and 131I treatment. This patients presentation raised questions about appropriate preoperative evaluation in this clinical scenario. This case highlights the importance of a thorough pre-operative work up for metastatic spine tumors. This should include evaluation of the thyroid consisting of thorough clinical history with particular attention to prior radiation exposure. Palpation of the thyroid also should be included as part of a routine pre-operative physical in cases of metastatic lesions of unknown origin. Thyroid function studies should not be utilized unless a clinical suspicion for thyroid cancer is raised during the examination.

Medical Management of Eosinophilic Granuloma of the Cervical Spine

We report a case of eosinophilic granuloma involving the vertebral bodies of the cervical spine in a 33-month-old girl. This lesion was diagnosed by needle biopsy and treated with prednisone and vinblastine therapy along with immobilization in a Minerva brace. The child has done well over a 9-month follow-up and has shown MRI evidence of resolution of the lesion, reestablishment of structural integrity within the cervical spine and potential reconstitution of the involved vertebral bodies.

Communicating Hydrocephalus Secondary to Diffuse Meningeal Spread of Wegener's Granulomatosis: Case Report and Literature Review

OBJECTIVE AND IMPORTANCE We present a very unusual case of diffuse spread of Wegeners granulomatosis causing hydrocephalus. CLINICAL PRESENTATION A 53-year-old man presented in 1985 with bilateral middle ear infections requiring myringotomies. During the next 18 months, he went on to develop a left Bells palsy. The patient then began to develop recurrent occipital headaches along with left sixth and seventh nerve palsies and a green nasal discharge requiring hospitalization. Workup included magnetic resonance imaging showing pronounced enhancement of the tentorium and meninges in the occipital region with normal ventricle size. An x-ray of the chest showed multiple pulmonary nodules. A regimen of prednisone and cyclophosphamide was initiated. The patient did well for 2 years until he again developed middle ear infections and headache. Serial lumbar punctures showed increased pressures. A circulating antineutrophil cytoplasmic antibody was positive. Cyclophosphamide was administered, with acetazolamide added for treatment of the elevated intracranial pressure. The patient stabilized for another 2 years but then presented in 1994 with recurrent headache, bilateral papilledema, and mild left arm and right leg weakness. A lumbar puncture was performed with an opening pressure of 52 cm H2O. Computed tomography of the head revealed moderate enlargement of the lateral third and fourth ventricles, consistent with communicating hydrocephalus. INTERVENTION A right frontal ventriculoperitoneal shunt was placed. A leptomeningeal biopsy performed at the side of catheter placement (far away from any meningeal enhancement revealed by magnetic resonance imaging) showed chronic meningitis and multinucleated giant cells. Cyclophosphamide therapy was begun again. The patient has not experienced recurrence of headache, cranial nerve deficits, or papilledema for more than 3 years. CONCLUSION This is the first reported case of diffuse involvement of the meninges from Wegeners granulomatosis. Fortunately, this patient responded well to shunting and sustained medical management. Although rare, Wegeners granulomatosis should be included in the differential diagnosis of chronic aseptic meningitis, communicating hydrocephalus, and papilledema.