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C Keohane

Publications and source records attributed to C Keohane.

45 records · Page 3Linked to original sources

Chondroblastoma of the skull.

A case of chondroblastoma of the temporal bone is reported, and the pathology of the lesion outlined. The rarity of these neoplasms in the skull makes accurate prognosis impossible.

Adult↗

Massive retroperitoneal ganglioneuroma presenting with small bowel obstruction 18 years following initial diagnosis.

BACKGROUND: Ganglioneuroma is a rare tumour of neural crest origin, which arises from maturation of a neuroblastoma. While previously considered to be non-functioning, they are now known to be frequently endocrinologically active. AIMS AND METHODS: We report a case of a massive retroperitoneal ganglioneuroma presenting with small bowel obstruction in an adult, 18 years after initial diagnosis. Urinary dopamine levels were elevated, but other catecholamines were within normal limits. This is the first report in the English-language literature of a retroperitoneal ganglioneuroma presenting with or causing intestinal obstruction. We also review the metabolic, radiological, and histological features of these tumours. Relevant publications were identified from a Medline search using the MeSH headings 'ganglioneuroma', 'retroperitoneal neoplasms' and 'intestinal obstruction', and also from the reference lists of retrieved articles. CONCLUSIONS: Ganglioneuroma can grow to a massive size and present in a varied manner. It should be included in the differential diagnosis of any large retroperitoneal or mediastinal mass, including those causing bowel obstruction.

Adult↗

Pathology of the central nervous system in 40 cases of acquired immune deficiency syndrome (AIDS).

The central nervous system was examined in 40 AIDS patients who died between August 1982 and 1987. The cases included two children born to intravenous drug abusers and 38 male adults. The brains of eight patients who had no clinical or radiological evidence of central nervous system involvement showed non-specific changes which included microglial nodules, perivascular mononuclear cuffs, mineralization of blood vessels and granular ependymitis. In 32 brains from patients with neurological symptoms, toxoplasmosis was the most frequent finding (19 cases) manifested by multifocal, necrotic lesions or a diffuse pseudo-encephalitic process. Other opportunistic infections included cytomegalovirus (eight cases), progressive multifocal leucoencephalopathy (two cases), cryptococcosis (one case), aspergillosis (one case), multiple bacterial microabscesses (one case) and Mycobacterium avium intracellulare (one case). Two patients had cerebral lymphoma. Subacute encephalitis with white matter lesions and multinucleated giant cells characteristic of HIV infection was present in 15 cases. Various combinations of all these infections were encountered in the same brain, sometimes in the same area and, occasionally, in the same cell.

Acquired Immunodeficiency Syndrome↗

Neuropathology and neurodegeneration in human immunodeficiency virus infection. Pathogenesis of HIV-induced lesions of the brain, correlations with HIV-associated disorders and modifications according to treatments.

A variety of HIV-induced lesions of the central nervous system (CNS) have been described, including HIV encephalitis, HIV leukoencephalopathy, axonal damage, and diffuse poliodystrophy with neuronal loss of variable severity resulting, at least partly, from an apoptotic process. However, no correlation could be established between these changes and HIV dementia (HIVD). From our study of HIV infected patients, it appeared that neuronal apoptosis is probably not related to a single cause. Microglial and glial activation, directly or indirectly related to HIV infection, plays a major role in neuronal apoptosis possibly through the mediation of oxidative stress. In our patients with full-blown AIDS, this mechanism predominated in the basal ganglia and correlated well with HIVD. Axonal damage, either secondary to microglial activation, or to systemic factors also contributes to neuronal apoptosis. Although massive neuronal loss may be responsible for HIVD in occasional cases, we conclude that neuronal apoptosis is a late event and does not represent the main pathological substrate of HIVD. The dementia more likely reflects a specific neuronal dysfunction resulting from the combined effects of several mechanisms, some of which may be reversible. Introduction of highly active antiretroviral therapy dramatically improved patient survival, however, its impact on the incidence and course of HIVD remains debatable. In our series, the incidence of HIVE has dramatically decreased since the introduction of multitherapies, but a number of cases remain whose cognitive disorders persist, despite HAART. The poor CNS penetration of many antiretroviral agents is a possible explanation, but irreversible "burnt out" HIV-induced CNS changes may also be responsible.

AIDS Dementia Complex↗

Pseudoaneurysm of the occipital artery: an unusual cause of persisting headache after minor head injury.

Post-traumatic pseudoaneurysms of the extracranial arteries in the scalp are uncommon sequelae of head injury. We report on a patient who presented four weeks after a minor head injury with a tender, pulsating and enlarging mass in the course of the left occipital artery. There was associated headache radiating to the vertex. Computed tomographic angiography confirmed the lesion to be a pseudoaneurysm of the occipital artery. The lump was resected with complete resolution of symptoms.

Adolescent↗