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Show f. Clill. NClIro-0l'hthll/ll/ol. 5: 105-108, 1Y85 " IYH5 Ravl'1l Prl'ss, Nl'W York Unilateral Pupillary Distortion: A Case Report ROSA A. TANG, M.D. TERRIA L. WINN, M.D. K. FRANCIS LEE, M.D. GUILLERi\10 MARROQUIN, M. D. LARRY PATCHELL, M.D. JOEL W. YEAKLEY, M.D. Abstract A 29-year-old white man who complained of episodic pupillary distortion in his right eye brought on by strenuous exercise was found to have a segmental Horner's syndrome in association with a hypoplastic internal carotid artery. There is a rare but interesting phenomenon that has been reported in which intermittent pupillary abnormalities occur in some patients. One segment of the iris appears to be pulled into a peak for a brief time and then returns to normal. Thompson, I in 1983, reported on 26 patients with these symptoms, 11 of whom had a Horner's sYndrome, and summarized the liter-ature. 2 - 6 . We describe a 29-vear-old white man who came to our neuro-ophthalmic clinic with a history of episodic pupillary distortion brought on by strenuous exercise. We believe this case represents an example of a segmental Horner's syndrome. Case Report A 29-year-old, blue-eyed Caucasian man came to our clinic with a 2-3 month history of episodic blurred vision in the right eye brought on when he was lifting weights. The patient reported that his vision would return to normal with cessation of the exercise. Several days prior to our evaluation, the patient had observed his pupils during one of these episodes and found From the Departments of Ophthalmology ([tA.T., T.L.W., G.M.) and Radiology (K.F.L., L.P., ).W.K.), Thl' University of Texas Health Science Center, Houston, Tl'xas. Write for reprillts to: R. A. Tang, M.D., Hl'rm,lnn Eye Center, 1203 Ross Sterling Avenue. Houston. IX 77ll:1tl. U.S.A. that the right pupil was "distorted." He drew it as an updrawn pupil in the superotemporaI quadrant. These episodes were not reported by the patient to be associated with pain, headache, or paresthesia. The patient also reports that his left pupil has been larger than his right pupil since childhood. On examination, the patient's corrected visual acuity was 20/20 in each eye. The pupillary exam revealed round pupils that measured 4 mm in the right eye and 5 mm in the left eye in semidark conditions; there was no anisocoria in the lighted environment. Direct, consensual, and near pupillary reflexes were normal. The patient's palpebral fissures measured 9 mm 00 and 10 mm as, and the near point of accommodation measured 36 cm in the right eye and 27 cm in the left eye. Slit lamp examination was normal without evidence of heterochromia. During the course of the examination, the patient experienced an episode of right pupillary distortion induced by exercise (Fig. 1). This episode lasted 30-40 s and then the right pupil returned to a normal round configuration (Fig. 2). A 1'k Paredrine (hydroxvamphetamine) test was positive (i.e., the involved right pupil dilated poorly, suggesting a partial postganglionic Horner's syndrome). The remainder of the ocular examination and the visual fields were normal. The patient's workup included blood chemistries, epinephrine blood levels before and after stress, and 24-h urinary YMA, met,lI1ephrine, and catechol,lmine levels, which were all normal. Radiographs of tl1l' chest, skull, thoracic spine, and sternum were all normal. The computed tomographic scan of the brain showed prominence of the left cavernous sinus and a slightly slanted sella from right to left (Fig. 3). Digital subtraction angiography of the carotid arteries and cavernous sinuses showed prominence of the left cavernous sinus and a poorly identified right carotid artery. 105 Unilatl"\11 I'upill,uy Distortion Figure 1. Episudic segmental right pupillary disturtiun 111 the supl'rlltemporal quadrant. Because of the poor identification of the right carotid artery, the patient underwent cerebral arteriography, which showed a hypoplastic right internal carotid artery with hypertrophy of several branches of the right external carotid artery. The right ophthalmic artery was reconstituted by hypertrophy of the posterior ethmoidal branch from the middle meningeal artery, with a normal-appearing choroidal blush in the right eye (Fig. 4), Discussion We theorize that focal spasm of the iris dilator muscle produced the distorted pupil in the patient described. Sympathetic innervational abnormalities to the dilator muscle are probably the causal factor in our patient. as abnormalities of innervation are often segmental. Thompsonl feels that the abnormalit~·causing pupillary distortion is of neural origin. He mentioned the possibility that the "peaked segments are supersensitive to catecholamines that reach the muscle via the aqueous" but dismissed it because, in many patients. the pupillary distortions occurred in different segments of the iris with different episodes. Howe\'er, in our patient, the same segment of the pupil distorted with each episode and it was this very same 106 Normal right pupil contIguration. Journal of Clinical Neuro-ophthalmology Tang et al. Figure 3. Cllmpult>d tlln1Llgraphic scan Llt the sellar regiLln in axial plant' with cLlntrast enhancement showing considerable asymmetry lli the ca\'ernuus sinuses, the leit side being markedly prominent (asterisk), Figure 4. A.: Reconstitution of thL' sl'gmental intL'rn,ll carotid ,utL'rI' via thL' hypL'rtruphic Vidi,1I1 artL'ry (brgt' ,lnu\Vs), B: Multiple small collateral channL'ls arL' still SL'l'n dt thL' sill' ut thL' sL'gmL'nt,]1 ocdusiun ut till' intl'rndl carutid (arrow) in the intermediate phase, C: The left cdrotid artL'riogrdm shows ,1 l'russ-tilling ul thL' right dntL'l'illl' ,1I1d middle cerebr,]I arteries via the anterior communicating drtL'ry, June 1985 107 Ullil,lll'r,ll l'upill'H\' l)iS[llrlillll Figure S. I'.Hl'dnnl' ll'st sho\\'lI1g sl'gnwnl,ll nghl HlIrnl'r', '\'ndwflle In the ,uperlllell1pUrdl pupdldr\' yuadrant. area that failed to dilate with hydroxyamphetamine administration. In another argument against the hypersensitivity denervation theon', Thompson1 reported that his patients did not describe the signs and symptoms usually associated with a sudden increase in levels of circulating catecholamines, i.e., tachycardia, tachypnea, anxiety, and piloerector activity, Interestingly, strenuous exercise was the precipitating factor in our patient's episodes. If the involved segment was truly hypersensitive, it would explain the focal dilation of the pupil with increased levels of circulating catecholamines during strenuous exercise. We agree with Thompson's statement that a Horner's pupil that does not dilate at all to hydroxyamphetamine is not likely to be supersensitive to aqueous norepinephrine only in a small segment of the iris sphincter. However, our patient does not fit into this category, as his pupils did dilate to hydroxyamphetamine except in the involved segment (Fig. 5). In summary, we feel that our patient had a segmental postganglionic Horner's syndrome, The damage to part of the sympathetic innervation to the pupillary dilator muscle may have occurred when the right carotid artery s~ffered its hypoplastic change. We feel that the area of 108 the right pupil that dilates with exercise represents a denervation hypersensitivity response to increased levels of circulating catecholamines. Acknowledgment We wish to thank H, Stanle\' Thompson, 11.1,0" for his critical re\'iew of the manuscript. References 1. Thompson,S,: Tadpole-shaped pupils caused by segmental spasm of the iris dilator muscle. Am, I. Opt/1Il11/1Ll1 96: -167--177, 1983, 2, Lowenstein, 0" and Levine, A. 5,: Pupillographic studies. Arch Ophthallllol, 31: 7-1-94, 195-1, 3. Walsh, F. B" and Hovt, \Y, F,: Clinical NCl/roOphthall/ lLl"\\.11 \'01. 1 (e~i. 3). Williams & Wilkins, Baltimore, 1%4, chap. -1, p, 523. -1, Smolin, G.: L'nilateral intermittent pupillary dilation. ,Ar"'1. Ophthl1/II/[1/. 81: 705-706, 1969. 5, Hallett, 11.1" and Cogan, O. G.: Episodic unilateral I1wdriasis in otherwise normal patients. Arch Ophthl1ll1lo/. 84: 130-136, 1970. 6. Edelson, R. N., and Len', O. L: Transient benign unilateral pupillary dilation in young adults. An"/r. NCliro/. 31: 12-14, 197-1. Journal of Clinical Neuro-ophthalmology |