J Neurosurg / Volume 113 / November 2010 J Neurosurg 113:1053–1058, 2010 1053 A ngiolipomAs of the CNS are rare, benign tumors originating in mesenchymal tissue and are con- stituted by a proliferation of mature fat cells and endothelial cells. 1,17,23,33 They most frequently develop in the epidural space of the spine, the cavernous spaces, and more rarely in the orbit. 2,5,8,10,12,13,15,16,18,22,24,26,28,31,35–37 Few publications have reported them outside of these locations, in particular at the level of the tectal lamina and the thalamus. 21,25 Angiolipomas represent an ana- tomopathological entity distinct from lipomas, and their anatomopathological substratum and localizations are different (they mainly develop along the midline: the cor- pus callosum, the quadrigeminal plate, and the interhemi- spheric fssure). 6,32,38 This new case of angiolipoma of the LSC and an extensive review of the literature (Table 1) prompted us to use a novel anatomical technique and ap- ply it to the LSC and its contents. This technique allowed us to soften the bony structures without altering the fat tissue and thus determine whether fat tissue was present in the LSC. The operative fndings in this case combined with the anatomical study we performed and a critical review of the published literature lead us to suggest that angiolipomas are a pathological illustration of the inter- periosteal dural concept. Case Report History and Examination. This 56-year-old woman with no signifcant medical history presented with head- ache and partial ophthalmoplegia that had been present for 2 months. Neurological examination revealed an in- complete extrinsic paralysis of CN III with ptosis and diplopia. Facial sensitivity was normal and visual acuity was 6/10° on the right and 10/10° on the left. Lateral sellar angiolipoma: a tumor illustrative of the extradural compartment of the neural axis Case report P atrick François, M.D., Ph.D., 1 ilyess ZeMMoura, M.D., 1 anne Marie BergeMer Fouquet , M.D., 2 Michel Jan, M.D., 1 anD stéPhane Velut , M.D., Ph.D. 1,3 Services de 1 Neurochirurgie et 2 d’Anatomie et Cytologie Pathologiques, Centre Hospitalier Régional Universitaire de Tours; and 3 Laboratoire d’Anatomie, Université François Rabelais de Tours, France Angiolipomas are rare tumors of the CNS that most frequently develop in the orbit, the cavernous space, and the epidural space of the spine. The authors report the case of a patient who presented with an angiolipoma of the cavern- ous space. Using data from the published literature and an experimental anatomical approach, they demonstrate that the cavernous space contains adipose tissue. Consequently, they suggest that angiolipomas constitute a characteristic tumor illustrating the interperiosteo-dural concept. The authors report the clinical, radiological, and histological data of a patient who presented with a tumor of the cavernous space. In addition, they prepared 2 encephalic extremities (4 cavernous spaces) using a special anatomical preparation consisting of an injection of colored neoprene latex followed by a 6-month immersion in a formaldehyde solution enriched with hydrogen peroxide to soften the bone structures (coronal sections) while leaving the fat in the cavernous space intact. This case report corroborates previously published clinical data and shows that the tumor was a hamartoma comprising mature fat cells associated with vascular proliferation. The tumor developed in the cavernous space, which is an interperiosteo-dural space extending from the sphenoid periosteum (osteoperiosteal layer) to the superior and lateral walls of the cavernous space (encephalic layer). This space represents an anatomical continuum extending from the coccyx to the orbit: the interperiosteo-dural concept. It contains fat tissue that is abundant at the level of the orbit and the epidural spinal space and sparser at the level of the cavernous spaces, as was shown in our anatomical study. The authors suggest that angiolipomas represent a characteristic tumor that illustrates the interperiosteo-dural con- cept because they essentially develop in the fat tissue contained in these spaces. (DOI: 10.3171/2010.1.JNS091031) key WorDs • anatomy • angiolipoma • cavernous sinus • fat • skull base surgery 1053 Abbreviations used in this paper: CN = cranial nerve; LSC = lateral sellar compartment. See the corresponding article in this issue, pp 1045–1052.