[Lipoma of the temporal region with cortical malformation and epilepsy. Clinicopathological study (author's transl)]

Cerebral lipoma and the underlying cortex of the temporal lobe: pathological features associated with the malformation

Intracranial lipomas are believed to be congenital malformations rather than true neoplasms, resulting from the abnormal differentiation of the meninx primitiva, the undifferentiated mesenchyme. We report here the surgical pathological features of a lipoma that was located on the cerebral surface of an abnormally formed fissure, and the underlying cortex of the middle temporal gyrus of a 20-year-old woman. The mass was composed of typical adipose tissue in which a large number of blood vessels were present. Thick connective tissue associated with the arachnoid membrane covered the cortical surface. The cortex exhibited a polymicrogyric configuration in which the cortical ribbon was abnormally undulated and excessively folded. Reelin-immunolabeled Cajal-Retzius-cell-like cells were observed frequently in the fused molecular layer. The cortical lamination underlying the molecular layer was poorly defined. Along the border between the connective tissue and cortical surface, there was a narrow zone in which the mesenchymal and neuronal tissues were intermingled, and where immunohistochemical and ultrastructural investigations disclosed disruption of the basal lamina, prominent astrocytosis, and abundant axonal and synaptic profiles. These findings suggest that focal disturbances in cerebral cortical development occur in association with the development of lipomas.

Intracranial lipoma of the sylvian fissure. Case report and review of the literature

The authors present a rare case of lipoma of the sylvian fissure found in a 34-year-old man who presented with seizures. The patient underwent craniotomy and an attempted resection of the lesion, which was initially believed to be a dermoid tumor. The imaging characteristics of dermoids and lipomas are extremely similar. Given the difference in the natural history and resectability of these lesions, lipomas should be included in the differential diagnosis of lesions with imaging characteristics similar to dermoids. Currently, tumor location, density of the lesion or computerized tomography scans, and signal homogeneity of the lesion on magnetic resonance images can help one to distinguish these radiographically similar, but pathologically different, entities. As this case confirms, resection of a sylvian fissure lipoma is extremely difficult and potentially dangerous; in addition it is unlikely to improve symptoms. A short review of 10 cases reported in the literature and therapeutic options for these lesions are also discussed.

Multiple intracranial lipoma: a case report

We report on a male epileptic patient, presently 27 years old, who has suffered complex-partial attacks for 19 years. Under treatment with carbamazepine the seizures were completely controlled. In addition, the patient exhibited partial hypopituitarism. CT and MRI revealed the presence of 2 lipomas, one located within the optico-chiasmatic cistern and the other one in the medial temporal lobe. To our knowledge, this combination of the generally rare lesions has not been described yet.

Lipomas of the frontal lobe

An extremely rare case of lipomas on the cerebral surface in a 65-year-old female is reported. The tumors were located both in an unusual fissure of the right frontal convexity and under the right frontal lobe associated with and surrounded by areas of focal cortical dysplasia. Angiograms revealed dilated branches of the right anterior cerebral artery associated with angiomatous tumor blushes. The etiology of the combination of the lipomas and the anomalies, and the angiographic features, are briefly discussed.

Lipoma of the sylvian region

An exceptional case of lipoma of the sylvian region is described and the other seven reported cases are reviewed. The sylvian fissure is the most rare site of intracranial lipomas. Sylvian lipomas may be asymptomatic or present with epileptic seizures due to irritation of the cortex of the sylvian fissure. Only two previous cases have been diagnosed during life by computerized tomography and operated on; the deep location of these lipomas and their adherences to the sylvian cortex and the branches of the middle cerebral artery make radical removal impossible and dangerous.

Lipoma of the insula. Case report

The authors present a case of lipoma of the insula. This 20-year-old man with grand mal seizure was diagnosed by computerized tomography, and improved satisfactorily following surgical intervention.