| OCR Text |
Show Journal of Clinical Neuro- ophthallllology 9< 3J: 165- 168, 1989 Arteriovenous Malformation of the Posterior Ethmoidal Artery as an Unusual Cause of Amaurosis Fugax The Ophthalmic Steal Syndrome W. Fritz, M. D., H.- J. Klein, M. D., and K. Schmidt, M. D. © 1989 Raven Press, Ltd" New York Summary: We report the case of a patient with arteriovenous malformation fed by a posterior ethmoidal artery, The pre- operative amaurotic attacks on the diseased eye subsided after removal of the malformation, Doppler sonographic examination of the peripheral ophthalmic artery showed an inversion of the blood flow direction postoperatively, We describe a concept of an ophthalmiC steal syndrome treated in this patient by removal of an ateriovenous malformation. Key Words: Ophthalmic steal syndrome- Arteriovenous malformation- Amaurosis fugax- Doppler sonography, From the Department of Neurosurgery, University of Ulm, District Hospital, Guenzburg, ERG. Address correspondence and reprint requests to Dr. Wolfram L Fritz, Department of Neurosurgery, UniversIty of Ulm, Bezirkskrankenhaus, 0- 8870 Guenzburg, ERG, 165 Amaurosis fugax, a common complaint of patients harboring internal carotid occlusive disease, presages increased morbidity and mortality from a major stroke ( 1- 4), Much rarer is monocular blindness based on other causes such as Moya Moya disease ( 5), temporal arteritis ( 4), or a drop in systemic blood pressure ( 6). We report an unusual case of transient amaurosis caused by a dural arteriovenous malformation located in the anterior fossa. CASE REPORT This 57- year- old white man reported repetitive attacks of blurred vision in his right eye. The first attack, which lasted for - 3 min, occurred 2 years previously. Thereafter, his vision cleared completely. He did not remember any previous ocular disease. One year later, because of neck pain radiating to his arms, a cervical myelogram was performed showing osteophytic spurs in the lower cervical area and cervical disc prolapses in C5- 6, C6- 7, and C7- Thl. Assuming that this was not only the cause of his pain, but also of impingement on the vertebral arteries with transient intracranial hypoperfusion, a Cloward procedure was performed in the lower three cervical levels ( 7). The intervertebral discs between C5- 6, C6- 7, and C7Th1 were removed by using an anterior approach, and autologous bone was interposed in each intervertebral space to create a bony fusion from C5 to Thl. Thereafter, his pain subsided, but ocular symptoms persisted. Two more amaurotic attacks occurred in the right eye, one lasting for 5 min and another, several months later, lasting - 30 s. Subsequently, he suffered decreasing vision for which 166 W. FRITZ ET AL. FIG. 1. Angiogram showing a right frontopolar dural arteriovenous malformation fed by an anterior ethmoidal artery ( arrow): ( a) preoperative image and ( b) postoperative image. two pairs of spectacles were prescribed by an ophthalmologist. This did not improve his vision. The intraocular pressure was mentioned to have been elevated, but subsequent measurements failed to substantiate this. He also complained of vertigo that occurred upon arising from bed, but subsided after some seconds. No hearing impairment was reported. He underwent angiography so that the cervical vascular tree could be visualized. Incidentally, an arteriovenous malformation was discovered that had its blood supplied through an anterior ethmoidal artery and drained to a bridging vein ( Fig. 1). On an enhanced computed tomographic scan, two small high- density areas were seen in the frontopolar region that were believed to be consistent with the arteriovenous malformation ( Fig. 2). Ophthalmologic examination before the operation showed a distant acuity of 20/ 20 in both eyes with hyperopia and presbyopia in both eyes. Goldmann perimetry revealed a right superior quadrantanopia in the right eye ( Fig. 3). Ocular mobility was unimpeded in all directions on both sides. Alternative (' ) ver test:" showed an exophoria, but I Clin Neuro- ophthalmol, Vol. 9, No. 3. 1989 prism diopters were not used. Fundoscopy revealed drusen on the right macula and a normal fundus on the left. We totally removed the angioma. Figure 4 presents the operative aspect. Except for hyposmia on the right, the patient's recovery was uneventful. FIG. 2. Enhanced computed tomographic scan showing two small, round, high- density areas contiguous with the inner table of the frontal base bone. This possibly reflects the arteriovenous malformation. AN UNUSUAL CASE OF AMAUROSIS FUGAX 167 .'~ FIG. 4. Operative aspect of the arteriovenous malformation ( arrows). 2 .. / .• s -' · U- · ~'_.':':.:.~- · - '' T' __ . ttl. ..:' ..... / ...~- -- l b /'" a I II. IJII ILJ U', ~~.. . " . ~ ... J;. v I FIG. 3. Goldmann perimetry of the left ( a) and right ( b) eye, Postoperative ophthalmologic evaluation showed a persistent right superior quadrant defect in the right eye. The blurring attacks had disappeared, Control angiography 2 months later showed no more arteriovenous shunt vessels ( Fig. 1b). Doppler sonographic examination preoperatively demonstrated a retrograde flow in the distal branches of the ophthalmic artery. Postoperatively, this flow reverted to its normal outward direction ( Fig. 5). The pattern of flow changed in that, preoperatively, the end- diastolic flow was 22 cmls, whereas, postoperatively, the diastolic baseline dropped to 12 cm/ s. DISCUSSION Amaurosis fugax normally presages atherosclerotic disease ( 1,3,4,6,8,9), which may lead to complete stroke in up to 10% of untreated cases ( 10). Other causes are rare ( 14- 16). When both eyes are involved, it can be the result of intrinsic vessel disease like Moya Moya ( 5), postprandial systemic hypoperfusion ( 6), or increased blood viscosity as in polycythemia ( 11). Our case is remarkable in that amaurosis fugax was the result of a steal phenomenon in the ophthalmic artery. To our knowledge, only two similar cases have been reported. One was a middle fossa arteriovenous malformation ( 12), and the other was a contralateral intracerebral arteriovenous malformation [ Kosary, cited in Bogousslavsky et ai. ( 12)]. In these cases, the exact anatomic link is missing and a systemic steal phenomenon probably caused the symptoms. We demonstrated in our patient a direct connection from the ophthalmic artery via an anterior ethmoidal artery to the malformation. Removal of the malformation abolished the obscurations. The Doppler sonographic examination showed a change in the flow of distal branches of the ophthalmic artery from a pathologically centripetal to a normal centrifugal direction. The initial diastolic flow, in our opinion, rep- I Clin Neuro- ophthalmol, Vol, 9, No. 3, 1989 168 W. FRITZ ET AL. a REFERENCES resents what Buedingen et a1. called a " brain supplying type of flow" ( 13) founded on the increased intracranial outflow resistance. The reduction of this elevated diastolic level after the operation could be the result of the complete removal of the angioma. FIG. 5. Doppler sonographic signals of distal branches of the ophthalmic artery, ( a) Preoperative image shows flow away from the probe toward the interior. The direction of flow is marked by the small arrow in upper right corner. Elevated diastolic baseline ( large arrow), ( b) Postoperative image shows reversed flow marked by small arrow in upper right corner. 1. Adams HP, Putman SF, Corbett JJ, Sires BP, Thompson HS. Amaurosis fugax: the results of arteriography in 59 patients. Stroke 1983; 14: 742- 4. 2. Gloor B, Mueller HR, Vozenilek E. Arterielle Verschlul3krankheiten im Augenbereich: Diagnostischer Beitrag der Dopplersonographie. Klin Monatsbl Augenheilkd 1985; 186: 161- 71. 3. Ringelstein ED, Koerber N, Zeumer H, Hunold W. Arterielle retinale Durchblutungstoerungen: eine dringliche 1ndikation zur dopplersonographischen Untersuchung des Carotisstromgebietes. Klin Monatsbl Augenheilkd 1983; 182: 133- 40. 4. Sorensen PN. Amaurosis fugax: an unselected material. Acta Ophthalmol 1983; 61: 583- 8. 5. Noda S, Nayesaka S, Setogawa T, Matsumoto S. Ocular symptoms of Moya Moya disease. Am J Ophthalmol 1987; 103: 812- 6. 6. Eisenberg E, Bental E. Postprandial transient painful amaurosis fugax. I Neurol 1986; 233: 209- 11. 7, Cloward RB. The anterior approach for removal of ruptured cervical discs. JNeurosurg 1958; 15: 602- 17. 8. Bogousslavsky J, Regli F. Cerebro- retinal ischemia after bilateral occlusion of internal carotid artery. Neuroradiology 1985; 27: 238- 47. 9. Harrison MJG, Marshall J. Arteriographic comparison of amaurosis fugax and hemispheric transient ischemic attacks. Stroke 1985; 16: 795-- 7. 10. Lethlean AK. Amaurosis fugax. Aust JOphthalmol 1983; 11: 34G-- 1. 11. Berdel WE, Theiss W, Fink U, Rastetter J. Peripheral arterial occlusion and amaurosis fugax as the first manifestation of polycythemia vera. Blut 1984; 48: 177- 80. 12. Bogousslavsky ], Vinuela F, Barnett HJM, Drake CG. Amaurosis fugax as the presenting manifestation of dural arteriovenous malformation, Stroke 1985; 16: 891- 3. 13, Buedingen H], von Reutern GM, Freund HJ. Oopplersonographie der extracraniellen Hirnarterien. Stuttgart: Thieme, 1982: 53- 84. 14. Hampton GR, Krohel GB. Gaze evoked blindness. Ann OphthalmoI1983; 15: 73- 6. 15. Kosmorsky GS, Rosenfeld SI, Burde RM. Transient monocular obscuration-? amaurosis fugax: a case report. Br J Ophthalmol 1985; 69: 688- 90. 16. Manor RS, Ben Sira J. Amaurosis fugax at downward gaze. Sun' OphthalmoI1987; 31: 411---< i. -[ 30 DFPTH 40 CURSOR 20 MEAH 101 PI 4MHz E ME JC2B ! Il' ... I ".:?~~~ 44 (: tI H: ~ j fl R ~ r"" t '- L.. Mf H .... lOt;. • ' I -, l~ o I Clin Neuro- ophthalmol, Vol. 9, No. 3, 1989 |
