Ventral "spinal epidural meningeal cysts"--not epidural and not cysts? Case series and review of the literature.

BACKGROUND: Ventral spinal epidural meningeal cysts are rare entities for which the pathogenesis is poorly understood. OBJECTIVE: We present the clinical, radiographic, surgical, and pathologic findings of 4 patients with extensive ventral spinal epidural meningeal cysts and review the relevant literature. In addition, we discuss a suspected mechanism for pathogenesis. METHODS: Four patients with anterior spinal epidural meningeal cysts are retrospectively reviewed. RESULTS: Ventral spinal epidural meningeal cysts are often large, extending on average from C2 to L1 in our series. Patients typically present with a prolonged course of symptoms and signs, including segmental muscle weakness and atrophy, subtle myelopathy, mild to moderate spinal pain, and headache. Histopathologic analysis of the cyst wall demonstrates collagenous tissue consistent with dura but without arachnoid features. Dynamic computed tomographic myelography is the study of choice for localization of the primary dural defect. Patient symptoms and neurological deficits routinely improve after appropriate surgical intervention. CONCLUSION: Diverse signs and symptoms herald the presentation of ventral spinal meningoceles. Intraoperative, radiographic, and pathological findings are all suggestive of an intradural dissection as the etiology. Hence, they may be more appropriately named "ventral spinal intradural dissecting meningoceles." Definitive treatment involves identification and obliteration of the dural defect.

Anomalous vertebral artery compression of the spinal cord at the cervicomedullary junction.

BACKGROUND: Myelopathy from ectatic vertebral artery compression of the spinal cord at the cervicomedullary junction is a rare condition. CASE DESCRIPTION: A 63-year-old female was originally diagnosed with occult hydrocephalus syndrome after presenting with symptoms of ataxia and urinary incontinence. Ventriculoperitoneal shunting induced an acute worsening of the patient's symptoms as she immediately developed a sensory myelopathy. An MR scan demonstrated multiple congenital abnormalities including cervicomedullary stenosis with anomalous vertebral artery compression of the dorsal spinal cord at the cervicomedullary junction. The patient was taken to surgery for a suboccipital craniectomy, C1-2 laminectomy, vertebral artery decompression, duraplasty, and shunt ligation. Intraoperative findings confirmed preoperative radiography with ectactic vertebral arteries deforming the dorsal aspect of the spinal cord. There were no procedural complications and at a 6-month follow-up appointment, the patient had experienced a marked improvement in her preoperative signs and symptoms. CONCLUSION: Myelopathy from ectatic vertebral artery compression at the cervicomedullary junction is a rare disorder amenable to operative neurovascular decompression.

Opticochiasmatic apoplexy in a five-year-old.

A 5-year-old female presented to the emergency department with a 24-hour history of nausea, vomiting and mental status changes. Imaging demonstrated hemorrhage from a suprasellar mass consistent with an optic nerve glioma. The patient was taken to surgery for an open biopsy and hematoma evacuation. Pathology revealed a grade 3 fibrillary astrocytoma. She was subsequently treated with carboplatin and vincristine and is now 2 years out without evidence of recurrence. Apoplexy is a rare presentation for an optic pathway glioma. To the authors' knowledge, this is the first reported case in the pediatric population. Clinical presentation appears similar to the symptoms observed in pituitary apoplexy. Timely surgery should be directed at obtaining diagnostic tissue, prevention of long-term nervous system damage and evacuation of the hematoma where feasible.

The neurosteroid allopregnanolone promotes proliferation of rodent and human neural progenitor cells and regulates cell-cycle gene and protein expression.

Our previous research demonstrated that the neuroactive progesterone metabolite allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one) rapidly induced hippocampal neuron neurite regression (Brinton, 1994). We hypothesized that allopregnanolone-induced neurite regression was a prelude to mitogenesis initiated by a rise in intracellular calcium. Supporting this hypothesis, the current data demonstrate that allopregnanolone, in a dose-dependent manner, induces a significant increase in proliferation of neuroprogenitor cells (NPCs) derived from the rat hippocampus and human neural stem cells (hNSCs) derived from the cerebral cortex. Proliferation was determined by incorporation of bromodeoxyuridine and [3H]thymidine, fluorescence-activated cell sorter analysis of murine leukemia virus-green fluorescent protein-labeled mitotic NPCs, and total cell number counting. Allopregnanolone-induced proliferation was isomer and steroid specific, in that the stereoisomer 3beta-hydroxy-5beta-pregnan-20-one and related steroids did not increase [3H]thymidine uptake. Immunofluorescent analyses for the NPC markers nestin and Tuj1 indicated that newly formed cells were of neuronal lineage. Furthermore, microarray analysis of cell-cycle genes and real-time reverse transcription-PCR and Western blot validation revealed that allopregnanolone increased the expression of genes that promote mitosis and inhibited the expression of genes that repress cell proliferation. Allopregnanolone-induced proliferation was antagonized by the voltage-gated L-type calcium channel (VGLCC) blocker nifedipine, consistent with the finding that allopregnanolone induces a rapid increase in intracellular calcium in hippocampal neurons via a GABA type A receptor-activated VGLCC (Son et al., 2002). These data demonstrate that allopregnanolone significantly increased rat NPC and hNSC proliferation with concomitant regulation in mitotic cell-cycle genes via a VGLCC mechanism. The therapeutic potential of allopregnanolone as a neurogenic molecule is discussed.