Interhemispheric lipoma: Interval development of an associated cyst

Abstract

We report a case of an 11-year-old patient who underwent CT imaging for complications of sinusitis, and showed incidental development of an interhemispheric cyst in association with an intracranial lipoma over a 10-year interval. Cysts and lipomas are well described in association with dysgenesis of the corpus callosum. We present an uncommon association, of a new cyst in association with an intracranial lipoma, in a patient with a normal corpus callosum.

Keywords: CT, computed tomography; MRI, magnetic resonance imaging.

Figure 1

11-year-old male with interhemispheric lipoma. Axial postcontrast CT image shows left ethmoid opacities and a thin, rim-enhancing fluid collection along the lamina papyracea of the medial left orbit, consistent with a subperiosteal abscess (arrow).

Fig. 2

11-year-old male with interhemispheric lipoma. Axial postcontrast CT images obtained at a level superior to the lateral ventricles (A at standard brain window, and B at expanded windows at levels) show a fluid-density, bilobed simple cyst along the falx, without rim enhancement, and without obvious extension into the lateral ventricles. There is a lipoma associated with the cyst (B, arrow) that extends from the right atrium of the lateral ventricle (C, arrow), adjacent to the choroid, to superiorly along the falx.

Figure 3

11-year-old male with interhemispheric lipoma. Midline, sagittal, T1-weighted image (A) from an MRI obtained 10 years before demonstrates a normal-appearing corpus callosum and a high-signal intensity band, consistent with an intracranial lipoma. Axial T1-weighted image (B) above the level of the corpus callosum, at approximately the level of the CT images shown in Figs. 2A-B, shows no cyst.