Effect of COX-2 inhibitor meloxicam against traumatic brain injury-induced biochemical, histopathological changes and blood-brain barrier permeability.

OBJECTIVE: The overproduction of reactive oxygen species and resultant damage to cellular proteins or lipids of cell membranes and DNA by free radicals are the underlying mechanisms of many neuropathologies. Cyclooxygenase-2 (COX-2) inhibitors have been suggested to be neuroprotective by reducing prostanoid and free radical synthesis, or by directing arachidonic acid metabolism through alternate pathways. This study investigated the putative neuroprotective effect of the COX-2 inhibitor, meloxicam, in a rat model of diffuse brain injury. METHODS: Sprague-Dawley rats were subjected to traumatic brain injury with a weight-drop device using 300 g(-1) m weight-height impact. The groups were: control, meloxicam (2 mg/kg, i.p.), trauma and trauma + meloxicam (2 mg/kg, i.p.). Forty-eight hours after the injury, neurological examination scores were measured, the animals were decapitated and brain tissues were taken. Brain edema and blood-brain barrier (BBB) permeability were evaluated by wet-dry weight method and Evans blue (EB) extravasation respectively. In brain tissues, malonedialdehyde, glutathione, myeloperoxidase and Na/K-ATPase levels were measured. RESULTS: The neurological examination scores mildly increased in trauma groups 48 hours after the induction of trauma. Meloxicam treatment improved the altered neurological status. The trauma caused a significant increase in brain water content that was partially reversed by meloxicam. Meloxicam also reduced the EB extravasation indicating the preservation of the BBB integrity. Meloxicam treatment also significantly reduced the increase in malondialdehyde and myeloperoxidase levels and restored glutathione content of the brains that had been significantly increased after trauma. CONCLUSION: Meloxicam exerts neuroprotective effect by preserving BBB permeability and by reducing brain edema (probably by its anti-inflammatory properties) in the diffuse brain injury model.

Imaging features of unusual intracranial cystic meningiomas.

OBJECTIVE: To describe the imaging features of unusual intracranial cystic meningiomas in infants and adults. METHODS: We retrospectively reviewed the magnetic resonance and computed tomography findings for 2 female patients and 3 male patients, ranging in age from 1 to 73 years (median 41 years), with histopathologically proven cystic meningioma. RESULT: Although cystic meningiomas usually appear as solid and cystic masses, they may present as a mainly multicystic lesion. The wall of a cystic part of the meningioma may include both enhancing and unenhancing areas at imaging. The cystic portion of a meningioma is hypointense on diffusion-weighted images and markedly hyperintense on corresponding apparent diffusion coefficient maps. CONCLUSION: Cystic meningiomas may vary in appearance at imaging. They can be very challenging when present in infants. Knowledge of imaging findings and awareness of variability in the differential diagnosis can help to avoid preoperative diagnostic pitfalls.

Pineal germinoma associated with multiple congenital melanocytic nevi: a unique presentation.

Intracranial germ cell tumors are rarely seen and typically localize in the pineal or suprasellar region. The largest category of germ cell tumors is the germinoma. There have been reported associations of malignant tumors and chromosomal abnormalities in germ cell tumors. In this study, we present a 22-year-old man with multiple congenital melanocytic nevi in association with pineal tumor. Congenital melanocytic lesions greater than 2 cm were counted to be 54 in number, and those smaller than 1 cm in diameter were found to be 25 in number. The pathological diagnosis of the pineal tumors was germinoma, and the lesions located in the occipital region and trunk were compound congenital nevi. To our knowledge, a relationship between multiple congenital melanocytic nevi and germ cell tumors has not been reported before. The connection between them remains to be clarified.

Accuracy and diagnostic yield of stereotactic biopsy in the diagnosis of brain masses: comparison of results of biopsy and resected surgical specimens.

The aim of this retrospective study was to investigate the diagnostic yield and accuracy of stereotactic biopsy in patients harboring brain mass. Stereotactic biopsy was performed in 130 patients between 1995 and 2000 in an educational and research hospital in Turkey. The results of histological analysis were compared to the resected specimens in 23 patients. The lesions were lobar in 62% of cases and deep-seated in 38% of cases. During the biopsy procedures, the pathologist was in the operating theatre and a very small fragment was used for cytological examination. No frozen section was used in any of the cases. Samples were diagnostic in 122 cases. The overall diagnostic yield of the procedure was 94%. A definitive histological diagnosis was not made in eight patients. The histological diagnoses of the two procedures were identical (complete agreement) in 16 cases. In three cases, the histological diagnoses between the two procedures were slightly different without impact on patient care (minor disagreement). The diagnosis of the stereotactic biopsy was completely changed after craniotomy in four cases (major disagreement). The accuracy of the histological diagnosis was 83%. There was only one major complication, which involved intracerebral hemorrhage. Despite the limited number of patients who underwent resection, our data suggest that stereotactic biopsy of brain masses is a safe and accurate technique that can obtain adequate tissue for histological diagnosis, thus providing the best avaible treatment for patients. Cytological evaluation of the streotactic biopsy also is a highly effective tool for obtaining sufficient material during the procedure in many cases.

Primary anaplastic large cell lymphoma of the central nervous system: prognostic effect of ALK-1 expression.

Anaplastic large cell lymphoma (ALCL) rarely occurs in the central nervous system. Although defined by its composition of large, pleomorphic, CD30-positive lymphocytes, ALCL is heterogeneous. Most are T cell but some are null cell. Most but not all have a characteristic 2:5 translocation producing the fusion protein ALK-1, which is reliably detected by immunohistochemistry. In systemic ALCL, ALK-1 expression correlates with young patient age and a favorable prognosis. Herein we report four new cases of primary central nervous system ALCL from the Mayo Clinic and incorporate additional data from five previously published cases. ALK-1 expression was determined in all nine tumors. Patient age was 4-66 years (mean 29 years) with a bimodal distribution: 6 < or = 22 years, 3 > or = 50 years. Six were female. Tumors were mostly supratentorial, five were multifocal, and seven had involvement of dura or leptomeninges. Seven tumors were T cell, two were null cell, and five of nine were ALK-1 immunopositive. Total mortality was six of nine. Three patients, 4-18 years of age (mean 13 years), were alive at 4.8-6.1 years postdiagnosis; these tumors were all ALK positive. Five patients, 13-66 years of age (mean 43 years), died of tumor 4 days to 11 weeks postdiagnosis; four of five of these tumors were ALK negative. One 10-year-old child with an ALK-positive tumor died of sepsis, but in remission. Central nervous system ALCL is aggressive. Our study suggests that a better outcome may be associated with young age and ALK-1 positivity, prognostic parameters similar to systemic ALCL.