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✓ A 6-month-old child with an isolated oculomotor nerve palsy was found to have a papillary meningioma infiltrating the nerve along its intracranial course adjacent to the midbrain. The clinical implications of this unusual histological variant are discussed.

✓ Despite technical advances, the ability to restore motor function following a brachial plexus avulsion is limited. Twenty patients who suffered the loss of elbow flexion following a brachial plexus avulsion injury underwent a neurotization procedure in an attempt to restore that lost function. Of 16 patients who underwent intercostal to musculocutaneous nerve anastomosis, seven obtained good elbow flexion. Four patients who no longer had a viable biceps brachialis muscle underwent an anastomosis between transposed intercostal nerves and a free vascularized gracilis muscle grafted to the position of the biceps. Two of these patients obtained good elbow flexion. Although synkinesis between the biceps brachialis and the inspiratory muscles can be demonstrated during coughing and deep inspiration, the patients learn to flex their reinnervated biceps brachialis muscle and maintain flexion independent of respiration.

✓ Seventeen patients with recurrent gliomas were treated with the combination of cyclophosphamide and vincristine. All but one had previously received and failed chemotherapy. Cyclophosphamide was administered at doses ranging from 250 to 1000 mg/sq m by intravenous infusion on Days 1 and 2, and vincristine was given at a dose of 1.0 mg/sq m (2 mg maximal dose) intravenously on Day 1; cycles were repeated every 4 weeks. Clinical and radiographic improvement was observed in eight of 16 evaluable patients, and four other patients had stabilization of previously progressive disease. Four patients are alive and off treatment without evidence of recurrence for a median period of 37 months; these included an adult with a cerebral anaplastic astrocytoma now more than 51 months after therapy. Toxicity included moderately severe myelosuppression that required hospitalization in seven patients. These results indicate that the combination of cyclophosphamide and vincristine has activity in the treatment of recurrent gliomas, and warrant the use of these drugs in larger controlled studies, particularly if they can be used in conjunction with hematopoietic growth factors.

✓ The development of the Cavitron ultrasonic surgical aspirator (CUSA) has facilitated neurosurgical intervention for removal of central or peripheral nervous system tumors adjacent to or within vital structures. However, laboratory studies defining the phenotypic and genotypic properties of these tumors, both in cell culture and as xenografts in immunoincompetent animals, require viable tumor fragments free of microbial or red blood cell contamination. This report describes the use of a readily available sterile trap with the CUSA which, in conjunction with centrifugation and ammonium chloride lysis of the bloody aspirate, allowed collection of concentrated viable human medulloblastoma tumor cells. These cells were successfully established in cell culture and as transplantable xenografts in athymic mice.

✓ The treatment and subsequent developmental progress of six children with dorsal third ventricular cysts are described. This cystic malformation has a radiological appearance which is superficially similar to that of the dorsal cyst of alobar holoprosencephaly, especially when the third ventricular cyst is large. Indeed, previous reports have identified this abnormality as a form of holoprosencephaly. However, careful study reveals that the dorsal third ventricular cyst is a distinct entity both developmentally and clinically. The six patients in this series were effectively treated with shunts, and their subsequent developmental progress was assessed by means of the Prescreening Developmental Questionnaire-Revised as well as the Bayley Scales of Infant Development. The nomenclature and differences between this entity and the holoprosencephalies are reviewed. The authors conclude that dorsal third ventricular cysts have a developmental and clinical course more similar to that of arachnoid cysts than to that of the holoprosencephalies.

✓ Six patients with optic pathway gliomas who were previously managed with surgery and/or chemotherapy were treated with carboplatin (560 mg/sq m) after radiographic evidence of disease progression. The median age at diagnosis was 2 years (range 4 months to 7 years), and the interval between diagnosis and carboplatin therapy ranged between 7 months and 6.5 years (median 1.8 years). Treatment was given at 4-week intervals and continued until unacceptable toxicity supervened, the disease progressed, or the disease was stable for 12 months. All patients demonstrated disease stability at the outset of the third cycle and continued to do so at the time of this writing. Two patients are 16 and 32 months from initial carboplatin therapy and have been off treatment for 5 and 14 months, respectively; two patients are still receiving therapy at 7 and 11 months after their initial treatment. During the study, two patients developed hypersensitivity to the drug, requiring its discontinuation. Toxicity was minimal, consisting mainly of thrombocytopenia, requiring a one-dose reduction in four of the six treated patients. No platelet transfusions were needed. These results suggest that carboplatin can arrest growth of progressive optic pathway gliomas in children and can allow delay of radiotherapy. A larger trial will be required to define the optimal use of carboplatin in the treatment of low-grade gliomas in children.

Object. The management of tethered spinal cord syndrome with onset of symptomatology occurring in adulthood remains controversial, although the necessity of early surgery in the pediatric tethered cord syndrome population is well established. To ascertain the results of surgery in adult patients with this anomaly, the authors undertook a retrospective review of 34 cases.

Methods. The authors studied the hospital records of 34 consecutive patients who presented in adulthood with tethered cord syndrome and conducted follow-up phone interviews with 28 of them. The population consisted of 12 men and 22 women, ranging in age from 18 to 70 years (mean 34 years). The most common presenting feature was pain, followed by weakness and incontinence. All patients underwent surgery. The most common operative findings were tight filum terminale, split cord malformation, and lipomyelomeningocele, paralleling those observed in pediatric studies.

Long-term surgical results and patient outcome ratings were encouraging. After a mean clinical follow-up period of 4 years, significant improvement occurred in 22 of 27 patients presenting with pain, 13 of 27 patients with motor or sensory dysfunction, and 11 of 18 patients with bowel and bladder disturbance. In addition, telephone interviews were obtained after a period of 8.6 years. Twenty-two (79%) of 28 patients called the operation a long-term success; 21 (75%) of 28 patients believed that they had significant postoperative improvement (and not just stabilization) in pain and/or neurological function. Surgical complications were generally minor.

Nineteen (86%) of 22 employed patients returned to work after surgery. Two (33%) of six patients who were not employed before surgery worked full time postoperatively. Only two of the 28 patients interviewed had received Workers' Compensation benefits; both of these had good outcomes and returned to work.

Conclusions. Tethered spinal cord syndrome in adults is an uncommon entity that can become symptomatic. Although surgery in adults involves greater risk of neurological injury than in children, it is a low-risk procedure with encouraging results. Because neurological deficits are generally irreversible, early surgery is recommended.

Object. To provide more information about this rare condition, the authors describe five cases of syringohydromyelia without hindbrain herniation. Preoperative magnetic resonance imaging with and without gadolinium—diethylenetriamine pentaacetic acid revealed no evidence of spinal cord tumor, arachnoiditis, or spinal dysraphism.

Methods. Craniocervical decompression was performed in all patients, after which there was resolution of the symptoms in the four symptomatic patients, and all five showed marked reduction in the size of the syrinx.

Conclusions. The authors hypothesize the rare occurrence of syringohydromyelia resulting from a Chiari-like pathophysiological condition but lacking a hindbrain hernia. Patients with this condition may benefit from craniocervical decompression.

Object. The cisternal portion of the trochlear nerve (fourth cranial nerve) can easily be injured during intracranial surgical operations. To help minimize the chance of such injury by promoting a thorough understanding of the anatomy of this nerve and its relationships to surrounding structures, the authors present this anatomical study.

Methods. In this study, in which 12 cadaveric heads (24 sides) were used, the authors describe exact distances between the trochlear nerve and various surrounding structures. Also described are relatively safe areas in which to manipulate or enter the tentorium, and these are referenced to external landmarks.

Conclusions. This information will prove useful in planning and executing surgical procedures in and around the free edge of the tentorium cerebelli.