Clinical and radiological features of pediatric cerebellar anaplastic oligodendrogliomas.

Oligodendrogliomas constitute 4-7% of primary intracranial gliomas in adult and 1% of primary central nervous system tumours in children. The authors report two unusual pediatric cases of anaplastic oligodendroglioma occurring in the cerebellum. The patient with a well-circumscribed lesion with 1p/19q co-deletion had a favorable outcome in comparison with the patient with a diffuse lesion and intact 1p/19q. The discussion elucidates the surgical outcome of such pediatric cerebellar anaplastic oligodendrogliomas in relation to their radiological findings.

Isolated sellar tuberculoma presenting with panhypopituitarism: clinical, diagnostic considerations and literature review.

Tuberculosis, a common cause for chronic intracranial infections can mimic varied intracranial pathologies including tumours. Pituitary tuberculomas are rare lesions and are often diagnosed pre-operatively as pituitary tumours. We report a case of a 31-year-old lady with a sellar-suprasellar lesion who presented with panhypopituitarism. The patient underwent a trans-nasal, trans-sphenoidal surgical decompression of the lesion. Histopathology revealed a tuberculous lesion in the pituitary. The characteristic radiological features of sellar tuberculomas are discussed along with a review of literature. Atypical sellar radiology in the presence of a thickened pituitary stalk could point to pathology other than pituitary adenoma, possibly a chronic inflammatory condition like tuberculoma.

Invasive sphenocavernous aspergilloma complicating an operated case of acromegaly.

There is a surge in fungal infections of the central nervous system due to an increase in the incidence of immunocompromised state and widespread use of antimicrobials. Despite myriad clinical presentations and skull base syndromes associated with Aspergillus infections, aspergilloma in the sella is relatively rare. We report a rare case of aspergilloma of the sella and parasellar region in a patient operated for acromegaly. A 30-year-old diabetic patient underwent two surgeries for a growth hormone-secreting pituitary adenoma, which included a transsphenoidal approach. During his last admission, magnetic resonance imaging revealed a heterogeneous mass in the sella, suprasellar region, sphenoid sinus, and cavernous sinus with multiple areas of necrosis. His presentation, surgical treatment, and response to antifungal therapy are discussed. The role of prior surgery and related comorbidities in developing the invasive granuloma are highlighted.

Coexisting intracranial tumors with pituitary adenomas: genetic association or coincidence?

The co-occurrence of two or more brain tumors with different histological features is rare. The authors report three rare cases of intracranial tumors associated with pituitary adenomas. Two of the pituitary tumors were functioning adenomas: a prolactinoma and a thyrotropin secreting adenoma. Two of the associated intracranial neoplasms were gliomas and one was a meningioma. Radiological and clinical examination for syndromal association was negative in all cases. We briefly discuss the presentation and treatment options of these cases and review the 19 previous publications in the literature of pituitary tumors occurring in association with other neoplasms and explore the possible links underlying these co-occurring neoplasms. Our three cases represent 0.86% of all pituitary tumors operated at our institute over a 9-year period.

Paradoxical embolus across atrial septal defect and posterior circulation infarct in neurosurgical patients.

Paradoxical embolism through a patent foramen ovale or atrial septal defect is increasingly recognized in association with embolic strokes, with the advent of modern echocardiography. The authors describe two neurosurgical cases with such an anomaly that suffered nonfatal embolic stroke in the cerebellum. The patients developed posterior inferior cerebellar artery infarcts, which were managed conservatively and had no neurological deficits. They evaluate possible factors for emboli to occur in a perioperative neurosurgical setting and provide a brief review of literature on preoperative management of patients with this cardiac defect. Closure of cardiac shunts is warranted before non-emergent neurosurgical operations. During emergency craniotomies, proper precautions should be taken to reduce the incidence of venous air embolism and paradoxical embolism.

Chronic brain abscess secondary to a retained wooden foreign body: diagnostic and management dilemmas.

A four-year-old child presented with recent onset generalized tonic clonic seizures. She was operated for a suspected intracranial tuberculoma and was found to harbor an intra-parenchymal retained wooden foreign body with a chronic abscess. The foreign body had entered the brain parenchyma after a minor head injury, sustained three years earlier. She was asymptomatic for the intervening three years. The initial diagnosis was missed by several physicians. A retained wooden fragment via a transtemporal apparently closed head injury is an extremely rare event. The present study reveals the diagnostic and therapeutic challenges and stresses the importance of high degree of suspicion to diagnose retained intracranial foreign bodies and the need for early surgical exploration, to avoid chronic and potentially life threatening neurological complications.

Diagnostic and clinical implications of pituicytoma.

Pituicytoma is a rare, indolent, benign tumor of the sellar and suprasellar region arising from pituicytes of the neurohypophysis. It is most often diagnosed pre-operatively as a pituitary adenoma. We report two patients with pituicytoma operated on at our Institute over 8 years. Imaging of one patient showed a parasellar and medial temporal extension, which has not been reported to our knowledge. The radiological features that help distinguish this low-grade tumor from other sellar and parasellar tumors are discussed along with its distinct histological findings. The authors also review the literature on its clinical presentation, diagnosis, surgical management and outcome.

Neurological complications and surgical outcome in patients with anterior choroidal segment aneurysms.

INTRODUCTION: Choroidal segment aneurysms occur in close relation to terminal internal carotid branches and concomitant anatomical variations in the anterior choroidal artery. The authors evaluate the demographics, presentation, operative techniques, and surgical outcome in 13 patients with this aneurysm. METHODS: After identifying the study group from a retrospective review of all supraclinoid ICA aneurysms operated in our institution over an 8-year period, analysis was done with respect to the radiological and operative findings and clinical follow-up. Statistical significance for outcome was analyzed using two-tailed Fisher's exact test (p < 0.05). RESULTS: The incidence of choroidal segment aneurysm was 3.02%. Six (46%) patients had Fisher grade III bleed on imaging. Nine (69%) patients had a good surgical outcome. Three patients had ischemic stroke in the anterior choroidal territory. Patient demographics, Hunt and Hess score at presentation, Fisher score on computed tomogram scan, aneurysm characteristics and clip configuration had no bearing on surgical outcome. CONCLUSIONS: In patients with anterior choroidal artery aneurysms managed surgically, meticulous surgical exposure, identification of anatomical variations of parent artery, appropriate clip selection and usage of intra-operative Doppler limit ischemic complications, and allay the development of the morbid clinical syndrome associated with anterior choroidal territory infarction.

Dipyridamole enhances ischaemia-induced arteriogenesis through an endocrine nitrite/nitric oxide-dependent pathway.

AIMS: Anti-platelet agents, such as dipyridamole, have several clinical benefits for peripheral artery disease with the speculation of angiogenic potential that could preserve ischaemic tissue viability, yet the effect of dipyridamole on ischaemic arteriogenesis or angiogenesis is unknown. Here we test the hypothesis that dipyridamole therapy augments arteriolar vessel development and function during chronic ischaemia. METHODS AND RESULTS: Mice were treated with 200 mg/kg dipyridamole twice daily to achieve therapeutic plasma levels (0.8-1.2 microg/mL). Chronic hindlimb ischaemia was induced by permanent femoral artery ligation followed by measurement of tissue perfusion using laser Doppler blood flow along with quantification of vascular density, cell proliferation, and activation of nitric oxide (NO) metabolism. Dipyridamole treatment quickly restored ischaemic hindlimb blood flow, increased vascular density and cell proliferation, and enhanced collateral artery perfusion compared with control treatments. The beneficial effects of dipyridamole on blood flow and vascular density were dependent on NO production as dipyridamole did not augment ischaemic tissue reperfusion, vascular density, or endothelial cell proliferation in endothelial NO synthase (eNOS)-deficient mice. Blood and tissue nitrite levels were significantly higher in dipyridamole-treated mice compared with controls and eNOS(-/-) mice, verifying increased NO production that was regulated in a PKA-dependent manner. CONCLUSION: Dipyridamole augments nitrite/NO production, leading to enhanced arteriogenesis activity and blood perfusion in ischaemic limbs. Together, these data suggest that dipyridamole can augment ischaemic vessel function and restore blood flow, which may be beneficial in peripheral artery disease.

Morphometric analysis of foramen magnum dimensions and intracranial volume in pediatric Chiari I malformation.

PURPOSE: Foramen magnum dimensions and intracranial volume in Chiari I malformations in children were studied, and the statistical relationship between patient demographics, radiological features and foramen magnum morphometry was investigated. METHODS: Linear measurements were used to calculate the intracranial volume using preoperative magnetic resonance images and computed tomogram images. The area of the foramen magnum was obtained independently using computer imaging software and a regression formula. The result of 21 pediatric patients was compared with a matched control group. RESULTS: The area of the foramen magnum was within the range of the expected value deduced using a formula based on the intracranial volume. There was no statistical difference in the area and linear dimensions of the foramen magnum in the study and control groups. Six patients (28%) had a foramen magnum in close proximity to a spherical shape. CONCLUSION: The authors provide a simple, accurate and reproducible method of estimating foramen magnum area in the pediatric Chiari I group. The irregular shape of the foramen magnum is accentuated by developmental bony and soft tissue anomalies at the cranio-vertebral junction in Chiari malformation. Consequently, an individualized cross-sectional assessment of the foramen magnum in relation to the hindbrain tissue in the same plane is required to study the initiation and propagation of the Chiari I symptomatology.

Adult medulloblastoma and the "dural-tail" sign: rare mimic of a posterior petrous meningioma.

The authors describe clinical and radiological features of a 32-year-old male patient with a posterior fossa lesion. The radiological characteristics resembled an extra-axial lesion; a meningioma, with attachment to the tentorium and petrous bone. The histological diagnosis was classical medulloblastoma. We review literature of this atypical presentation of medulloblastoma and "dural-tail" sign, which can be associated with other benign or malignant lesions. The role of magnetic resonance spectroscopy in the diagnosis of primitive neuroectodermal tumors is discussed.

Increased expression of p53 protein correlates with the extent of myocyte damage in cardiac allograft rejection.

Acute cardiac allograft rejection (ACAR) has been associated with a poor prognosis. The early diagnosis of ACAR necessitates the accurate detection of myocyte damage. Nuclear damage activates p53, a transcription factor that initiates apoptosis and repair. Endomyocardial biopsies (n=25) from 10 cardiac allograft recipients were stained for nuclear p53. The biopsies were divided into rejection groups based on the grading of ACAR: group 1, grade 0; group 2, grade Ia and Ib; group 3, grades II and III. While clinical indices did not correlate with myocyte damage, significantly more myocytes in group 3 stained for nuclear p53 (2.48+/-0.60/mm(2)) compared with group 1 (0.22+/-0.12/mm(2)) and group 2 (0.43+/-0.18/mm(2)). Increased expression of p53 in cardiac myocytes with grade II or grade III rejection provides an objective quantification as an aid in the diagnosis of ACAR.

Therapies to increase high-density lipoprotein cholesterol and their effect on cardiovascular outcomes and regression of atherosclerosis.

Epidemiological studies have shown that decreased level of high-density lipoprotein (HDL) cholesterol (C) is an independent inverse predictor of coronary artery disease (CAD) even in patients with normal levels of low-density lipoprotein (LDL)-C. There is an abundance of evidence in favor of statins and aggressive LDL-C lowering therapy for both primary and secondary prevention of CAD. In contrast, the evidence for reduction of CAD risk with HDL-C raising therapy is relatively thin, partly due to the paucity of effective and safe drugs for increasing HDL-C level. However, there are emerging new therapies for raising HDL-C level and growing evidence in favor of pharmacologic therapies to raise HDL-C level. We present in this article a review of pharmacologic therapies that are currently available to increase HDL-C level, their safety and efficacy in relation to cardiovascular endpoints.