Interhemispheric osteolipoma with agenesis of the corpus callosum

Abstract

Osteolipoma is an ossified lipoma with distinct components of fat and bone. We present a case of interhemispheric osteolipoma associated with total agenesis of the corpus callosum. A 20-year-old man complained of severe headache, nausea and vomiting. Brain computed tomography showed a low-density mass in an interhemispheric fissure, with high T1 and T2 magnetic resonance signals compatible with fat. The mass measured 4.9 x 2.9 cm in size and showed peripheral calcifications. There was another small piece of same signal mass within the lateral ventricular choroid plexus. The interhemispheric lesion was removed by an interhemispheric approach. Osteolipoma is rare in interhemispheric region, however, it should be a differential diagnosis of lesions with fat intensity mass and calcifications.

Keywords: Agenesis; Corpus callosum; Intracranial; Lipoma; Osteolipoma.

Fig. 1

Computed tomography (A) shows a fatty mass with peripheral calcification in the interhemispheric fissure (white arrow), and a separate lipoma in the left lateral ventricle (black arrow). Magnetic resonance T1-non-enhanced sagittal (B) and coronal (C) images show corpus callosal agenesis and vascular voids.

Fig. 2

Microscopic view of the tumor showing lobules of mature adipose tissue separated by strands of fibrous connective tissue and lamellar bone islands (H & E, ×100).