E1035. Collections of Characteristic Findings and Anatomic Locations of Intracranial Lipomas
Authors
Jeong Hyun Yoo;
Mokdong Hospital
Background
Intracranial lipomas are rare brain lesions and the incidence is variable from 0.06 - 0.46% among intracranial tumors. It is thought to be congenital malformation resulting from persistence and maldifferentiation of meninx primitiva. Lipomas show variable locations, but most commonly located at subarachnoid space because of meninx primitive origin, and tendency to locate at the midlines such as pericallosal, quadrigeminal, suprasellar areas. The purpose of study is to understand the embryologic pathogenesis of the intracranial development and to illustrate the typical intracranial lipomas located in the various typical sites, and to illustrate the associated with various congenital anomalies.
Educational Goals / Teaching Points
To understand the embryologic pathogenesis of the intracranial development, illustrate the typical intracranial lipomas located in the various typical sites, and illustrate the associated with various congenital anomalies.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
We retrospectively reviewed CT or MR images of intracranial lipomas in 45 patients. We classified according to their location and shapes. We also noted accompanied intracranial anomalies. There were 48 intracranial lipomas in 45 patients. All of those showed high SI on T1WI, low SI on T2WI MR, and noted as hypodensity on CT without contrast enhancement. The most common site was pericallosal (18 cases, 37.5%). And most of pericallosal lipomas <em>n</em> = 16) were found at posterior aspect, but only 2 were found at anterior aspect. Next most common location was quadrigeminal area (16 cases, 33.3%). Third most common site was suprasellar area (<em>n</em> = 9, 18.7%). Thirty one lipomas showed tubulonodular shapes, and 17 showed curvilinear shapes (35.4 %). Eight lesions showed flow voids in them. One lesion showed dark SI foci meant calcification existed. We found 23 associated other intracranial anomalies (47.9%). Corpus callosal anomalies were most common abnormalities, which were in 13 cases with variable findings from agenesis to hypogenesis. Seven of them were associated with pericallosal lipomas, and four of them with quadrigeminal lipomas, and last two of them with suprasellar lipomas. Associated posterior fossa anomalies included Chiari I malformation and hypoplasia of vermis or midbrain.
Conclusion
Intracranial lipomas are rare and they most frequently located in the midlines such as pericallosal, and quadrigeminal and suprasellar area. They showed tubulonodular or curvilinear shapes. They show high frequency of accompanied other brain malformations.