M. Beatriz S. Lopes
Roy C. Selby and Nilo M. Lopes
✓ Three new cases of cryptococcal granuloma of the central nervous system are reported and compared with 37 previously described cases. The lesion may appear with or without evidence of meningitis. Resection of the granuloma followed by prophylactic or therapeutic chemotherapy is recommended as the treatment of choice. Serial lumbar punctures and blood and CSF antigen levels are of value in determining response to treatment.
M. Beatriz S. Lopes
The majority of patients with acromegaly harbor a functioning growth hormone (GH) pituitary adenoma. Growth hormone–secreting adenomas correspond to about 20% of all pituitary adenomas. From the histopathological point of view, a variety of adenomas may present with clinical signs and symptoms of GH hypersecretion including pure GH cell adenomas (densely and sparsely granulated GH adenomas), mixed GH and prolactin cell adenomas, and monomorphous adenomas with primitive cells able to secrete GH and prolactin including the acidophilic stem cell adenoma and the mammosomatotroph cell adenoma. In this article, the author reviews the main pathological features of the GH-secreting adenomas and some of the molecular genetics mechanisms involved in their pathogenesis.
Melike Mut, M. Beatriz S. Lopes and Mark Shaffrey
Dr. Lucien Rubinstein is best remembered for his significant contributions to the field of neuropathology, particularly in the classification of nervous system tumors. His accomplishments in basic neuro-oncology and in the formulation of diagnostic principles reflected a unique talent for synthesizing fundamental clinicopathological concepts based on skillful diagnostic investigation and a thorough understanding of neurobiology. Dr. Rubinstein was the leader in the establishment of cell cultures from central nervous system (CNS) tumors. He meticulously analyzed both light and electron microscopic features of CNS tumors, recorded his findings, and patiently drew sketches to be shared generously with his colleagues and students. As a pioneer in neuropathology, in his work Dr. Rubinstein set the foundation for many enduring concepts in neurosurgery, neuro-oncology, neurology, and basic tumor biology.
Veetai Li, Demetrius K. Lopes and Gregory J. Bennett
✓ Commercially available anterior cervical internal fixation devices are designed for placement in adults and older children. Use of these systems in preschool-aged children is precluded due to the small size of their cervical vertebral bodies (VBs). The authors describe a 2-year-old boy who suffered a C3–4 injury, resulting in complete ligamentous disruption. Because of the gross cervical instability, they elected to perform surgery via posterior and anterior approaches, supplemented with internal fixation, during the same operation. The purpose of the anterior internal fixation device is to deliver compressive forces onto the interbody graft and keep it in place, thus optimizing the potential for a successful fusion. Because of the discrepancy in size between the VBs and the plate and screws, however, the authors were unable to use any of the standard anterior cervical fixation devices. Instead, they implanted a craniofacial miniplate, and the patient was required to wear an external halo brace. The miniplate provided enough stability to allow for a solid fusion. The authors believe that this technique is a reasonable option in young children who require anterior cervical fixation.
Amos O. Dare, Demetrius K. Lopes and Walter Grand
Arnaldo Neves Da Silva, Maria Beatriz Lopes and David Schiff
✓ Primary central nervous system lymphoma (PCNSL) is a rare form of primary brain neoplasm, accounting for less than 3% of all primary brain tumors. Ninety percent of cases involve a large B-cell lymphoma that presents as a homogeneously enhancing lesion or lesions, typically deep-seated in the brain parenchyma. The authors describe unusual pathological forms of PCNSLs, including low-grade, T-cell, and Burkitt types, and also rare presentations such as neurolymphomatosis and pituitary lymphomas.
M. Beatriz S. Lopes and Edward R. Laws Jr.
Low-grade tumors of the central nervous system constitute 15 to 35% of primary brain tumors. Although this category of tumors encompasses a number of different well-characterized entities, low-grade tumors constitute every tumor not obviously malignant at initial diagnosis. In this brief review, the authors discuss the pathological classification, diagnostic procedures, treatment, and possible pathogenic mechanisms of these tumors. Emphasis is given in the neu-roradiological and pathological features of the several entities.
A prospective 6-month study
Sepehr Sani, Kirk W. Jobe and Demetrius K. Lopes
Until recently, wide-necked aneurysms were not considered amenable to treatment with coil embolization. The recent introduction of intracranial stents has provided a method of preventing coil migration out of wide-necked aneurysms. The Neuroform2 Treo is a modification of the Neuroform stent; the new version has a higher metal/artery ratio. The authors' initial experience with the use of this stent in combination with coil embolization to treat wide-necked intracranial aneurysms is reported and technical considerations are discussed.
The authors' first 10 consecutive patients with wide-necked intracranial aneurysms were included in this study. Inclusion criteria restricted the group to adult patients with wide-necked intracranial aneurysms (ruptured and unruptured lesions). A wide neck was defined as a dome/neck ratio of less than 2 or a neck that was 4 mm or wider as measured on angiograms. Immediate postprocedure angiography studies were performed to determine successful coil occlusion of the aneurysm as well as patency of the parent vessel. Six-month follow-up angiograms were obtained in all patients.
Ten aneurysms with poor dome/neck ratios (< 2) were studied in 10 patients. In all cases the stent was delivered to the aneurysm site and positioned without difficulty. No branch artery compromise was observed. A technical difficulty occurred in one case, with prolapse of a coil into the parent vessel, which was successfully corrected with no adverse clinical effects. There were no clinical or neurological complications associated with endovascular treatment of aneurysms in this series. One patient required further coil embolization because of findings on the 6-month follow-up cerebral angiogram.
The Neuroform2 Treo navigates similarly to the Neuroform2, with the advantage of increased aneurysm neck coverage. This feature may lower the retreatment rates for wide-necked cerebral aneurysms.