Vascular Tentorial dural arteriovenous fistula presenting symptoms due to mass effect on the dilated draining vein: case report Yasushi Iwamuro, MD T , Ichiro Nakahara, MD, Toshio Higashi, MD, Mitsutoshi Iwaasa, MD, Yoshihiko Watanabe, MD, Eishu Hirata, MD, Kenzo Tsunetoshi, MD, Mahmoud Taha, MD Department of Neurosurgery, Kokura Memorial Hospital, Kitakyushu, Fukuoka 802-003, Japan Received 16 May 2005; accepted 19 July 2005 Abstract Background: Tentorial dural arteriovenous fistula (AVF) presented symptoms due to mass effect on the dilated draining vein. We report a patient presenting left hemisensory disturbance because of compression of the midbrain by a dilated draining vein of the AVF. The AVF has disappeared completely by drainer clipping after feeder embolization. Case Description: A 66-year-old woman presented with left hemisensory disturbance due to compression of the midbrain by a dilated draining vein with tentorial dural AVF. On admission, she complained of left hemisensory disturbance. Enhanced computed tomography (CT), magnetic resonance imaging, and magnetic resonance angiogram revealed the midbrain compressed by a mass lesion, which was a draining vein with AVF fed by numerous feeding arteries neighboring the right tentorial edge. The single-photon emission CT (SPECT) did not depict any laterality. Conclusion: This is a rare case of a tentorial dural AVF which caused left hemisensory disturbance not by venous congestion, but by a compression of the midbrain by the dilated draining vein, because SPECT showed no laterality. In this case, magnetic resonance angiogram, 3-dimensional CT angiography, and SPECT were useful in the diagnosis and planning the strategy for treatment. D 2006 Elsevier Inc. All rights reserved. Keywords: Tentorial dural arteriovenous fistula; Mass effect; Draining vein 1. Introduction Tentorial dural AVF is a rare situation [1]. This type of AVF is often accompanied by varix of the leptomeningeal draining vein and presents neurological disturbances be- cause of venous congestion visible by SPECT. Feeder embolization and/or drainage clipping is often selected as treatment of tentorial dural AVF. We report a case of a 66-year-old woman who complained of left heminumbness because of a dilated venous pouch compressing the brainstem. We diagnosed the case as tentorial dural AVF via findings of MRI and conventional angiography. As with most tentorial dural AVF, the venous drainage in this case appeared in the dilated leptomeningeal vein. However, the SPECT did not depict any laterality; therefore, we conclud- ed that the symptom was caused not by venous congestion, but by a compression of the midbrain by the dilated draining vein. The treatment of this case was a 2-stage operation: first, an endovascular feeder embolization and, second, a lateral suboccipital craniotomy, clipping the draining vein. Postoperative angiogram revealed disappearance of the AVF, and the patient left the hospital with mild ataxia. 2. Case report A 66-year-old woman without a history of disease became conscious of left heminumbness in July 2003 and consulted our institution. At the first medical examination, she was alert and complained of heminumbness on the left 0090-3019/$ – see front matter D 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.surneu.2005.07.076 Abbreviations: 3D-CT, 3-dimensional computed tomography; AVF, arteriovenous fistula; CT, computed tomography; MRI, magnetic resonance imaging; MRA, magnetic resonance angiogram; SPECT, single-photon emission computed tomography. T Corresponding author. Tel.: +81 93 921 2231; fax: +81 093 921 8497. E-mail address: yiwamuro@tc4.so-net.ne.jp (Y. Iwamuro). Surgical Neurology 65 (2006) 511 –515 www.surgicalneurology-online.com