Absence of a Sphenoid Wing in Neurofibromatosis Type 1 Disease: Imaging with Multidetector Computed Tomography Omer Onbas, MD1 Cihangir Aliagaoglu, MD2 Cagatay Calikoglu, MD3 Mecit Kantarci, MD1 Mustafa Atasoy, MD4 Fatih Alper, MD1 Index terms : Neurofibromatosis Computed tomography Korean J Radiol 2006;7:70-72 Received October 6, 2004; accepted after revision March 16, 2005. 1Ataturk University, School of Medicine, Department of Radiology, Erzurum, Turkey; 2Erzurum Numune Hospital, Department of Dermatology, Erzurum, Turkey; 3Erzurum Numune Hospital, Department of Neurosurgery, Erzurum, Turkey; 4Ataturk University, School of Medicine, Department of Dermatology, Erzurum, Turkey Address reprint requests to: Omer Onbas, MD,Terminal mah. Somunoglu cad Esatpasa Apt B Blok No: 3/7 Erzurum, Turkey. Tel. +90 442 2361212-1521 Fax. +90(442) 2361301 e-mail: oonbas@hotmail.com 70 Neurofibromatosis type 1 disease is characterized by pigmented cutaneous lesions and generalized tumors of a neural crest origin and it may affect all the systems of the human body. Sphenoid dysplasia is one of the characteristics of this syndrome and it occurs in 5-10% of the cases; further, abnormalities of the sphenoid wings are often considered pathognomonic. However, complete agene- sis of a sphenoid wing is very rare. We report here on an unusual case of neurofi- bromatosis type 1 disease with the associated absence of a sphenoid wing that was diagnosed by using multidetector computed tomography. N eurofibromatosis type 1 (NF-1) is a relatively common autosomal dominant disorder that occurs in one in 3,000 live births. It is a hamartomatous disorder that originates in the neural crest and is charac- terized by neural tumors, cafe-au-lait spots, and Lisch nodules. Skeletal signs include scoliosis, sphenoid wing dysplasia, bony distortion and local cystic and erosive change. Although sphenoid wing dysplasia has been observed in between seven to 12.8 percent of patients with neurofibromatosis, the absence of a sphenoid wing is very rare (1 3). We report here an unusual case of NF-1 with an associated absence of a sphenoid wing by using multidetector computed tomography (MDCT). CASE REPORT A 31-year-old white man was admitted to our hospital with complaints of severe head pain and cross-eyed right globe. Physical examination revealed a normotensive man with cafe-au-lait spots on his chest and abdomen (Fig. 1). An ophthalmic examination revealed that his vision was normal except his right cross-eyed towards out paralysis and enophthalmos. Another notable finding was the discovery of a family history of neurofibromatosis. The patient was accepted for radiological evalua- tion in our clinic. MDCT was performed using an Aquilion scanner (Toshiba Medical Systems, Tokyo, Japan) with 16 high-resolution detectors. The images were obtained to define the caudocranial extent of the neck to the head region, by using a collimation of 1 mm 16 rows, with a helical pitch of 3, a gantry rotation speed of 0.75 sec per round, voltage of 120 kV and current of 300 mA. Three-dimensional images were reconstructed using maximum intensity projection (MIP) and 3D rendering algorithms on a Vitrea 2 (Vital Image Inc) workstation. The anterior volume rendered 3D CT image showed details of a bony defect in the right orbital region (Fig. 2A). Thick multiplanar axial reconstructions (MPR) revealed the absence of the right sphenoid wing, and the intracranial and orbital contents were separated only by dura mater (Fig. 2B). In addition, the transverse bone window Korean J Radiol 7(1), March 2006