196 Gotoh et al. cerebral infarction in its territory of supply was demonstrated on CT angiography. The site of DVT and source of emboli was not established; – no DVT was identified in the calves on Doppler studies, but origin in the pelvic venous system is most likely. The presence of the ovarian carcinoma may theoretically have predisposed to the development of pelvic DVT by local mass and pressure effects, producing venous stasis, and by inducing a hypercoagulable state. One other case of paradoxical embolism with cerebral infarction arising in association with ovarian carcinoma has been reported.6 In that case, unlike the current case, a femoral deep vein thrombosis was demonstrated and the ovarian carcinoma was advanced and surgically unresectable. The current case therefore represents another example of the association between ovarian carcinoma and paradoxical embolism resulting in cerebral infarction. daily life. In our search only four reported cases involved the SCA. Clinical manifestation and treatment for patients with cerebellar arterial dissections are discussed. ª 2003 Elsevier Ltd. All rights reserved. Journal of Clinical Neuroscience (2004) 11(2), 196–199 0967-5868/$ - see front matter ª 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S0967-5868(03)00136-X Keywords: arterial dissection, cerebral infarction, posterior circulation, subarachnoid haemorrhage, superior cerebellar artery Received 10 February 2003 Accepted 15 April 2003 Correspondence to: Toshiyuki Takahashi, MD, Department of Neurosurgery, Kohnan Hospital, 4-20-1 Nagamachiminami, Taihaku-ku, Sendai 982-8523, Japan. Tel.: +81-22-248-3585; Fax: +81-22-304-1641; E-mail: toshi@nsg.med.tohoku.ac.jp REFERENCES 1. Webster MW, Chancellor AM, Smith DL et al. Patent foramen ovale in young stroke patients. Lancet 1988; 2: 11–12. 2. Hanna JP, Sun JP, Furlan AJ et al. Patent foramen ovale and brain infarct. Echocardiographic predictors, recurrence and prevention. Stroke 1992; 25: 782–786. 3. Lechat P, Mas JL, Lascault G et al. Prevalence of patent foramen ovale in patients with stroke. NEJM 1988; 5: 1148–1152. 4. d’Audiffret A, Pillai L, Dryjski M. Paradoxical emboli: the relationship between patent foramen ovale, deep vein thrombosis and ischaemic stroke. Eur J Vasc Endovasc Surg 1999; 17: 468–471. 5. Travis JA, Fuller SB, Ligush J. Diagnosis and treatment of paradoxical embolus. J Vasc Surg 2001; 34: 860–865. 6. Mitsui T, Aoki Y, Nagata Y, Kojima Y, Tanaka K. Patent foramen ovale complicated by paradoxical embolism and brain infarct in a patient with advanced ovarian cancer. Gynecol Oncol 83: 608–609. INTRODUCTION In the past two decades, intracranial arterial dissection has received attention as an uncommon but important cause of ischaemic stroke and subarachnoid haemorrhage (SAH). Major arterial trunks, particularly the vertebral arteries, are the most common sites of dissection; these account for more than 90% of reported cases.1;2 Nontraumatic dissection of more peripheral arteries such as the superior cerebellar artery (SCA) is extremely rare. To date, only four cases of SCA dissection have been reported.3–6 Here we report two additional patients and review previous reports of cerebellar artery dissection. CASE REPORTS Dissection of the superior cerebellar artery: a report of two cases and review of the literature Hisaharu Gotoh1, Toshiyuki Takahashi1, Hiroaki Shimizu1, Masayuki Ezura2, Teiji Tominaga1 1 Department of Neurosurgery, Kohnan Hospital, Sendai, Japan, 2Department of Neuroendovascular Therapy, Kohnan Hospital, Sendai, Japan Summary Arterial dissections frequently involve the main trunk of the posterior circulation and are recognised as an important cause of stroke in young individuals. However, dissection confined to cerebellar arteries is rare. We encountered two patients with superior cerebellar artery (SCA) dissection. A 37-year-old man presented with dysarthria, right limb ataxia, and severe headache. Magnetic resonance imaging revealed cerebellar infarction in the right SCA territory. Angiography demonstrated stenosis and fusiform dilation of the SCA in the anterior pontine segment. Recovery with antiplatelet treatment was nearly complete. A 45-year-old man was admitted with decreased consciousness after sudden onset of headache. Computed tomography demonstrated subarachnoid haemorrhage with hydrocephalus. Angiography revealed fusiform dilation of the left SCA in the anterior pontine segment. After ventricular drainage, endovascular embolisation was performed without ischaemic complications. The patient’s condition improved sufficiently to return to Journal of Clinical Neuroscience (2004) 11(2) Case 1 A 37-year-old man had a severe occipital headache accompanied by vertigo with onset early in the morning. On the next day the patient additionally noted dysarthria and right limb ataxia, and then presented to our hospital. On admission, cerebellar ataxia on the right side and dysarthria were both evident. Complaints included headache, vertigo, and nausea. The patient had a history of hypertension without medical treatment. On magnetic resonance (MR) images, an infarct was demonstrated in the right cerebellar hemisphere. MR angiography obtained 1 day after onset revealed stenosis and aneurysmal dilation of the right SCA in the anterior pontine segment. Digital subtraction angiography 12 days after onset showed findings similar to those of MR angiography. The patient received antiplatelet therapy and was discharged home with only slight cerebellar ataxia (cf. Fig. 1). Case 2 While driving, a 45-year-old man had a sudden onset of severe occipital headache. He became semicomatose during ambulance transport to the hospital. On admission, computed tomography revealed SAH predominantly involving the prepontine cistern. Bilateral miosis and ataxic respiration were noted. The neurologic condition was designated as Hunt and Kosnik grade 4. Angiography disclosed fusiform dilation of the left SCA in the anterior pontine segment. Arterial dissection was also found in the horizontal portion of the left anterior cerebral artery. Under general anaesthesia, we first placed an intraventricular drain to relieve hydrocephalus. Then the patient underwent embolisation of the ª 2003 Elsevier Ltd. All rights reserved. Dissection of the superior cerebellar artery 197 Fig. 1 Case 1. An axial FLAIR magnetic resonance image (A) shows infarcts in the territory of the right superior cerebellar artery (SCA). Vertebral angiography (B) demonstrates stenosis and fusiform dilation (arrow) in the anterior pontine segment of the right SCA. SCA proximal to the fusiform dilation using a Guglielmi detachable coil. After embolisation, the fusiform dilation disappeared from angiograms, while the peripheral SCA was filled by collateral flow from the left inferior cerebellar artery. Following the procedure, the patient’s neurologic condition showed a fair degree of improvement, permitting him to return to daily life. Seven months after the SAH, the aneurysmal dilation of the anterior cerebral artery was trapped surgically without neurologic complication (cf. Figs. 2 and 3). DISCUSSION Arterial dissection currently is recognised as an important cause of stroke, particularly in young adults. Idiopathic intracranial arterial dissections often involve the vertebral and basilar arteries but are rare in peripheral arteries. Isolated dissections arising from arterial branches of the posterior circulation appear to be particularly rare. Twenty-six dissections of the cerebellar arteries have been reported including our present cases (Table 1).3–24 Only four of Fig. 2 the previous dissections arose in the SCA, while 17 involved the posterior inferior cerebellar artery (PICA), and three involved the anterior inferior cerebellar artery (AICA). Dissections of the SCA occurred in relatively young patients (mean age, 42.5 years) as did dissections of other cerebellar arteries (mean age, 43.6 years). In contrast to male preponderance for dissections of vertebrobasilar arteries, 13 (50%) of the 26 patients with dissection of cerebellar arteries were female. Of 25 patients with cerebellar artery dissection, 22 had dissections arising from the proximal segment near the brainstem; only three cases had dissections arising from the distal segment. In our review, 15 cases (58%) of dissections of the cerebellar artery presented with SAH, while 11 cases (42%) presented with ischaemia. Headache was a major symptom even in patients with purely ischaemic consequences of cerebellar artery dissections and no SAH. Of 11 patients with ischaemia from cerebellar artery dissections, 10 presented with headache accompanied by neurologic deficits. Takagi25 reported that 81% of patients with ischaemia from vertebrobasilar artery dissections had headache; in these cases 45% showed headache preceding the Case 2. Computed tomography on admission shows a wide zone of subarachnoid haemorrhage in the prepontine cistern, as well as hydrocephalus. ª 2003 Elsevier Ltd. All rights reserved. Journal of Clinical Neuroscience (2004) 11(2) 198 Gotoh et al. Fig. 3 Case 2. Angiographic findings. Preoperative vertebral angiography (A) demonstrates fusiform dilation (arrow) in the anterior pontine segment of the left superior cerebellar artery (SCA). Repeat angiography after coil embolisation (B) demonstrates complete occlusion of the left SCA (arrow) and filling of the peripheral SCA by collateral flow from the left inferior cerebellar artery. Table 1 Summary of cases of dissection of the cerebellar arteries Authors Age/ gender Involved vessels Side/site Clinical manifestation Surgery Friedman and Drake (1984) Ueki et al. (1987) Komiya et al. (1988) Nishino et al. (1991) Yamaura et al. (1991) Takahashi et al. (1992) Nagahiro et al. (1993) Kawaguchi et al. (1993) Mizushima et al. (1994) Fransen and De Tribolet (1994) Tikkakoski et al. (1997) Jafer et al. (1998) Shinoda et al. (1998) Yamashita et al. (2001) Wakamoto et al. (2002) 46/M 47/F 37/M 51/F 68/F 47/M 59/F 22/F 31/M 29/M 29/F 44/F 34/F 48/M 47/M 34/M 32/M PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA PICA rt. ant. med. seg. rt. ant. med. seg. lt. ant. med. seg. lt. televelotonsi. seg. lt. tonsilohemi. seg. lt. ant. med. seg. lt. tonsilohemi. seg. lt. lat. med. seg. lt. ant. med. seg. lt. ant. med. seg. lt. ant. med. seg. lt. lat. med. seg. lt. post. med. seg. rt. ant. med. seg. bit. ant. med. seg. lt. lat. med. seg. lt. ant. med. seg. Headache, vertigo SAH Headache, Wallenberg syndrome SAH SAH Headache, vertigo SAH SAH Headache, Wallenberg syndrome Headache, Wallenberg syndrome Headache, Wallenberg syndrome SAH SAH SAH SAH Headache, consciousness disturbance Headache, Wallenberg syndrome Encasement Wrapping Proxymal clipping Clipping and resection Entrapment Conservative Clipping Trapping and resection Trapping and bypass Resection and bypass Proxymal clipping Trapping and resection Coil embolisation Wrapping Conservative Conservative Conservative GR GR GR GR GR GR GR GR GR GR GR GR GR GR D GR GR Saito et al. (2000) Hancock and Millar (2000) Matsuyama et al. (2002) 68/F 60/M 39/F AICA AICA AICA lt. lat. pontomed. seg. lt. lat. pontomed. seg. lt. ant. pont. seg. SAH Vertigo, facial palsy, hearing loss SAH Coil embolisation Conservative Coil embolisation MD GR GR Kalyan-Raman et al. (1983) Ikeda et al. (1999) Mizutani et al. (2001) Araki et al. (2002) Present cases 38/M 37/F 34/F 64/F 37/M 45/M SCA SCA SCA SCA SCA SCA rt. ant. pont. seg. rt. ant. pont. seg. INA lt. ant. pont. seg. rt. ant. pont. seg. lt. ant. pont. seg. Headache, vertigo SAH SAH SAH Headache, vertigo, ataxia SAH Conservative Clipping and wrapping Trapping and bypass Coating Conservative Coil embolisation D GR INA V GR GR Outcome The blank lines across the table separate the cases according the artery involved. AICA, anterior inferior cerebellar artery: PICA, posterior inferior cerebellar artery; SCA, superior cerebellar artery; ant.med.seg., anterior medullary segment; televelotonsi. seg., televelotonsillar segment; tonsilohemi. seg., tonsilohemispheric segment; lat. med. seg., lateral medullary segment; post. med. seg., posterior medullary segment; lat. pontmed. seg., lateral pontomedullary segment; ant. pont. seg., anterior pontine segment; INA, information not available; GR, good recovery; D, died; MD, moderate disability; V, vegetative state. ischaemic event and 53% showed headache at the time of the ischaemic event. An ischaemic event together with headache is an important diagnostic clue in patients with dissections of the cerebellar artery, as it is in other vertebrobasilar artery dissections. Based on histologic findings, intracranial arterial dissections can be classified into two types. The subintimal type occurs beJournal of Clinical Neuroscience (2004) 11(2) tween the internal elastic lamina and the media, while the subadventitial type develops between the media and the adventitia. Intradural arteries lack an external elastic lamina and have a thinner adventitia than systemic arteries. The vertebrobasilar system therefore may be predisposed to adventitial disruption with consequent SAH, although the subintimal type of dissection also ª 2003 Elsevier Ltd. All rights reserved. Ganglioglioma of the spinal cord 199 is common in the posterior circulation. Pathologic investigation by Mizutani et al. 5 suggested additional factors in haemorrhage: risk of bleeding was related to extent of disruption of the media and to an entry-only type of dissection. Optimal treatment of patients with cerebellar artery dissection has not been completely established. Management strategy differs between ischaemic and haemorrhagic presentations. For patients with ischaemic symptoms, surgical procedures such as proximal occlusion of the parent artery, trapping with bypass, and encasement had been favored until the early 1990s. Recently, however, several authors have advocated conservative therapy for management of patients with ischaemia. Wakamoto et al.22 and Yamashita et al.23 conservatively managed ischaemic patients with PICA dissection; their angiographic findings improved in association with a favourable clinical course. Of 11 patients with an ischaemic presentation, six were treated conservatively with good results except in one patient (Table 1). Currently conservative management may be the treatment of choice for dissections of the cerebellar arteries presenting with ischaemia. In contrast to patients with ischaemic symptoms, surgical management usually is required when SAH is present; 14 of 15 patients with SAH underwent surgery in the presently reviewed cases. Surgical procedures, however, varied among patients. Of 14 patients, four underwent surgical occlusion of the parent artery by trapping or entrapment of the site of dissection, with or without bypass surgery. Endovascular techniques of coil embolisation were applied in four recently reported patients, with favourable results. In six other patients, the parent arteries were preserved by clipping, coating, or wrapping techniques. Outcomes of these varied procedures ware favourable except in one patient who underwent coating of the dissected SCA. Selection of a surgical procedure to treat dissection of the SCA with SAH should be individualised depending on the neurologic condition, development of collateral circulation from the AICA, PICA, or contralateral SCA, and the configuration of the dissection. When sacrifice of the SCA is necessary, the perforating arteries supplying the brainstem from the anterior pontine segment of the SCA should be considered because dissection occurs most frequently in that segment. When the perforating arteries already are involved in the dissection, proximal occlusion will not cause brainstem infarction, but while these arteries still are intact great care must be taken to preserve them during occlusion of the parent artery. REFERENCES 1. Schievink WI. Spontaneous dissection of the carotid and vertebral arteries. N Engl J Med 2001; 344: 898–906. 2. Yamaura A, Watanabe Y, Saeki N. Dissecting aneurysms of the intracranial vertebral artery. J Neurosurg 1990; 72: 183–188. 3. Araki T, Fujiwara H, Murata H, Sampei T, Taki W. Subarachnoid hemorrhage due to ruptured dissecting aneurysm of peripheral superior cerebellar artery. No Shinkei Geka 2002; 30: 1345–1351. 4. Ikeda K, Shoin K, Taguchi H, Yamano J, Kawahara R. Postpartum dissecting aneurysm of the superior cerebellar artery: case report. Neurol Med Chir (Tokyo) 1999; 39: 852–857. 5. Mizutani T, Kojima H, Asamoto S, Miki Y. Pathological mechanism and threedimensional structure of cerebral dissecting aneurysms. J Neurosurg 2001; 94: 712–717. 6. Kalyan-Raman UP, Kowalski RV, Lee RH, Fierer JA. Dissecting aneurysm of superior cerebellar artery. Its association with fibromuscular dysplasia. Arch Neurol 1983; 40: 120–122. 7. Fransen P, de Tribolet N. Dissecting aneurysm of the posterior inferior cerebellar artery. Br J Neurosurg 1994; 8: 381–386. 8. Friedman AH, Drake CG. Subarachnoid hemorrhage from intracranial dissecting aneurysm. J Neurosurg 1984; 60: 325–334. 9. Hancock JH, Millar JS. Spontaneous dissection of the anterior inferior cerebellar artery. Neuroradiology 2000; 42: 535–538. 10. Jafer J, Kamiryo T, Chiles BW, Nelson PK. A dissecting aneurysm of the posteroinferior cerebellar artery: case report. Neurosurgery 1998; 43: 353–356. ª 2003 Elsevier Ltd. All rights reserved. 11. Matsuyama T, Okuchi K, Norimoto K, Ueyama T. Ruptured dissecting anterior inferior cerebellar artery aneurysm: case report. Neurol Med Chir (Tokyo) 2002; 42: 214–216. 12. Mizushima H, Sakaki K, Kunii N et al. Dissecting aneurysm in the proximal region of the posterior inferior cerebellar artery presenting as Wallenberg’s syndrome: case report. Neurol Med Chir (Tokyo) 1994; 34: 307–310. 13. Nagahiro S, Goto S, Yoshioka S, Ushio Y. Dissecting aneurysm of posterior inferior cerebellar artery: case report. Neurosurgery 1993; 33: 739–742. 14. Nishino A, Sakurai Y, Niizuma H, Satoh H, Kayama T. Dissecting aneurysm of distal posterior inferior cerebellar artery: case report and review of the literature. No To Shinkei 1991; 43: 381–386. 15. Kawaguchi S, Sakaki T, Kamada K, Iwanaga H, Takehashi K. Dissecting aneurysm of the posterior inferior cerebellar artery: case report. Neurol Med Chir (Tokyo) 1993; 33: 634–637. 16. Komiya H, Saeki N, Iwadate Y, Sunami K, Yamaura A. Posterior inferior cerebellar artery dissecting aneurysm presenting with Wallenberg’s syndrome: case report. Neuro Med Chir (Tokyo) 1988; 28: 404–408. 17. Saito M, Ezura M, Takahashi A, Yoshimoto T. An arterial dissection of the distal anterior inferior cerebellar artery treated by endovascular therapy. No Shinkei Geka 2000; 28: 269–274. 18. Shinoda S, Murata H, Waga S, Kojima T. Bilateral spontaneous dissection of the posteroinferior cerebellar arteries: case report. Neurosurgery 1998; 43: 357–359. 19. Takahashi I, Takamura H, Gotoh S et al. Dissecting aneurysm of posterior inferior cerebellar artery: a case report. No Shinkei Geka 1992; 20: 277–281. 20. Tikkakoski T, Leinonen S, Siniluoto T, Koivukangas J. Isolated dissecting aneurysm of the left posterior inferior cerebellar artery: endovascular treatment with a Guglielmi detachable coil. Am J Neuroradiol 1997; 18: 936–938. 21. Ueki K, Teraoka A, Yoshida S, Hori T. Dissecting aneurysm of the posterior inferior cerebellar artery: a case report. No Shinkei Geka 1987; 15: 1215–1219. 22. Wakamoto H, Orii M, Miyazaki H, Ishikawa N. A dissecting aneurysm of the posterior inferior cerebellar artery was reduced spontaneously during conservative therapy. No Shinkei Geka 2002; 30: 425–429. 23. Yamashita Y, Hayashi S, Saitou H, Teramoto A. Dissecting aneurysm of posterior inferior cerebellar artery-studied by serial angiography. No Shinkei Geka 2001; 29: 1057–1062. 24. Yamaura A, Isobe K, Karasudani H, Tanaka M, Komiya H. Dissecting aneurysms of the posterior inferior cerebellar artery. Neurosurgery 1991; 28: 894–898. 25. Takagi M. Clinical features and current status of diagnosis and management of vertebrobasilar artery dissections in Japan. Brain and Nerve 2002; 54: 203–211. Ganglioglioma of the spinal cord: Report of two cases and review of literature G.D. Satyarthee, V.S. Mehta, S. Vaishya Department of Neurosurgery, All India Institute of Medical sciences, New Delhi, India Summary Ganglioglioma can involve any part of the central nervous system. Mostly ganglioglioma occur in temporal lobe. Spinal cord ganglioglioma is a very rare entity. We report two cases of cervicodorsal region ganglioglioma, who underwent complete surgical excision. In the postoperative period they had transient deterioration of their neurological status that gradually recovered with follow-up. ª 2003 Elsevier Ltd. All rights reserved. Journal of Clinical Neuroscience (2004) 11(2),199–203 0967-5868/$ - see front matter ª 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S0967-5868(03)00124-3 Keywords: ganglioglioma, spinal cord, neurosurgery, management Journal of Clinical Neuroscience (2004) 11(2)