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Show Journal of Neuro- Ophthalmology 14( 1); 49- 51, 1994. © 1994 Raven Press, Ltd., New York Internuclear Ophthalmoplegia in Sickle Cell Trait Jacqueline A. Leavitt, M. D., and Salim I. Butrus, M. D. An 8- year- old boy presented with symptoms compatible with a right internuclear ophthalmoplegia. Magnetic resonance imaging showed a high- intensity signal on T2- weighted images at the level of the medial longitudinal fasciculus. Laboratory evaluation was positive only for sickle cell trait. Sickle cell trait is an uncommon cause for brainstem infarction. Key Words: Cerebrovascular infarction- Internuclear ophthalmoplegia- Magnetic resonance imaging- Medial longitudinal fasciculus- Sickle cell trait. From the Department of Ophthalmology, George Washington University Medical Center, Washington, D. C., U. S. A. Address correspondence and reprint requests to Dr. Jacqueline A. Leavitt, Department of Ophthalmology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, U. S. A. Sickle cell trait is associated with cerebral ischemic events but rarely with brainstem infarctions. We present a case of an 8- year- old black boy with sickle cell trait and internuclear ophthalmoplegia with skew deviation. CASE REPORT An 8- year- old boy presented to Children's Hospital National Medical Center for evaluation of his eyes. He had been poked in the right eye 1 day before admission. He rubbed the right eye and complained that it itched. He was referred by his teacher who noted disconjugate gaze. He denied any diplopia, pain, headache, head trauma, seizure history, or previous history of crossed eyes. On examination he was afebrile, well-developed, well- nourished, alert, and oriented. Cranial nerves IV through VIII and X through XII were intact. A slightly decreased gag reflex was noted. The remainder of the neurologic examination was normal. His head turned to the left. His uncorrected vision was 20/ 40 in each eye. Cyclo-plegic refraction was + 4.50 + 0.50 X 90 on the right and + 3.50 + 0.50 x 90 on the left. Minimal ptosis was present, more on the right than the left. Pupils were 4 mm on the right and 3 mm on the left and briskly reactive without an afferent pupil defect. Motility examination revealed marked underaction of the right medial rectus, with 60 A right exotropia and 30 A right hypertropia. Abduction nystagmus was present on the left. Slit- lamp examination revealed only + 1 injection of the in-feronasal conjunctiva on the right. Fundus examination was normal. Normal studies included Lyme disease antibody titer, cryptococcal antibody, urinalysis, urine drug screen, thyroid functions, clotting studies, throat culture for streptococcus, electrolytes, purified protein derivative and anergy panel, Monospot 49 50 }. A. LEAV1TT AND S. 1. BUTRUS screen, chest radiograph, antithrombin III, fibrinogen, cholesterol, triglycerides, antinuclear antibody, anti- DNA, protein C, and protein S. Rhino-virus was cultured from a specimen from his nasopharynx. Spinal tap revealed 100 erythrocytes; 14 leukocytes ( 87% lymphocytes, 13% mononuclear cells); protein, 34 mg/ dl; and glucose, 56 mg/ dl. Results of the Gram stain were negative. Cultures for bacteria, acid- fast bacilli, fungi, and virus were negative. The concentration of IgE in cerebrospinal fluid was less than 5 mg/ dl ( IgG was lost). Hemoglobin electrophoresis demonstrated 39.6% hemoglobin S; the remainder was hemoglobin A. Magnetic resonance imaging ( Fig. 1) showed a recent infarction of the central pons on the right, just below the level of the oculomotor nucleus. Recent infarction of the right medial thalamus and scattered periventricular white matter lesions were also seen on magnetic resonance images ( Figs. 2 and 3). Nine days after presenting with right- sided in-ternuclear ophthalmoplegia, the patient was readmitted because of 3 days of ataxia and two episodes of aphasia. His ocular examination was unchanged except that the conjunctival injection had cleared. Neurologic examination revealed intact reflexes without clonus, negative Romberg test, poor heel- to- shin response on the right, dysmetria, and FIG. 1. Axial T2- weighted magnetic resonance image shows high- signal intensity lesion ( arrow) to the right of midline at the level just inferior to the oculomotor nucleus. / Neum- Ophlhnlmol, Vol. 14, No. 1, 1994 FIG. 2. Axial T2- weighted magnetic resonance image shows high- signal intensity lesion ( arrow) in the right thalamus. grossly normal gait. Left vertebral angiography revealed normal filling of the entire vertebrobasilar system, with the left posterior inferior cerebellar artery supplying both sides of the posterior cerebellum. He was dismissed from the hospital and lost to follow- up. DISCUSSION Cerebrovascular complications occur in up to 17% of patients with sickle cell anemia ( HbSS) ( 1). The majority of these events are vaso- occlusive. Cerebral infarcts account for a 4% to 13% mortality FIG. 3. Axial T2- weighted magnetic resonance image shows multiple high- signal intensity lesions ( arrows) in the periventricular white matter. INTERNUCLEAR OPHTHALMOPLEGIA 51 rate and a 50% to 70% morbidity rate. Most of the strokes occur in patients younger than age 15 years. The incidence of stroke in sickle SC disease ( HbSC) was reported in 1972 by Portnoy and Herion ( 2) to be 1.7% in a study of 227 patients. Central nervous system infarcts in HbSS occur most often and most extensively in the areas supplied by the distal branches of the internal carotid artery. Few cases of spinal cord infarction have been noted in HbSS; rarer still are brainstem infarcts. Adams and colleagues ( 3) studied 25 patients with HbSS and cerebral infarction by computed tomography or magnetic resonance imaging. They concluded that large- vessel disease was the cause for infarction in 72% of infarcts in HbSS. Pavlakis and colleagues ( 4) performed magnetic resonance imaging in 18 HbSS cases with stroke and found both large- and small- vessel disease contributed to the cerebral infarction. The arteriographic study of 14 HbSS patients with cerebral infarction by Gerald and coworkers ( 5) was normal in 4 of 14. Posterior circulation was studied in only 5 of 14 and was normal. The vascular appearance was not pathognomonic for HbSS, and they recommended that posterior circulation need not be examined. Similar studies have not been reported in sickle cell trait disease. There are many causes for ischemic internuclear ophthalmoplegia: basilar artery disease, diabetes mellitus, systemic hypertension, systemic lupus erythematosus, migraine headache, brainstem angioma, arteriovenous malformation and aneurysm, and Fabry's disease ( 6). To our knowledge, this is the first case of a patient with sickle cell trait who presented with an internuclear ophthalmoplegia. Head trauma has also been reported as the cause of internuclear ophthalmoplegia in 18 cases ( 7), but those cases involved major blows to the head and not a simple poke to an eye, as in our patient. Multiple white matter lesions may also be consistent with demyelinating disease. The Poser classification defines definite multiple sclerosis as two attacks lasting 24 hours with clinical evidence of separate lesions and separated by 1 month ( 8). By this classification, our patient is outside the definition of definite multiple sclerosis. Magnetic resonance imaging is sometimes helpful in distinguishing ischemic changes from demyelinating changes. Changes that are hypointense on Tl- weighted images and hyperintense on T2- weighted images can be either ischemic or demyelinating. Distribution of these changes may distinguish the two entities. Lesions at the gray- white interface are consistent with small- vessel infarction. The thalamic lesion on magnetic resonance imaging is also an unusual location for demyelina-tion and is more consistent with ischemia. Also in the differential diagnosis of ischemic changes on magnetic resonance imaging would be moya moya disease, systemic lupus erythematosus, and neurofibromatosis. Our patient's angiogram was not consistent with the diagnosis of Moya Moya disease. His clinical examination and laboratory evaluations eliminated the consideration of the other two entities. REFERENCES 1. Grotta JC, Manner C, Pettigrew LC, Yatsu FM. Red blood cell disorders and stroke. Stroke 1986; 17: 811- 7. 2. Portnoy BA, Herion JC. Neurological manifestations in sickle- cell disease: with a review of the literature and emphasis on the prevalence of hemiplegia. Ann Intern Med 1972; 76: 643- 52. 3. Adams RJ, Nichols FT, McKie V, McKie K, Milner P, Gam-mal TE. Cerebral infarction in sickle cell anemia: mechanism based on CT and MRI. Neurology 1988; 38: 1012- 7. 4. Pavlakis SG, Bello J, Prohovnik I, et al. Brain infarction in sickle cell anemia: magnetic resonance imaging correlates. Ann Neurol 1988; 23: 125- 30. 5. Gerald B, Sebes JI, Langston JW. Cerebral infarction secondary to sickle cell disease: arteriographic findings. AjR 1980; 134: 1209- 12. 6. Miller NR ( ed). Walsh and Hoyt's clinical neuro- ophthalmology, 4th ed., Vol. 2. Baltimore: Williams & Wilkins; 1985: 710. 7. Keane JR. Traumatic internuclear ophthalmoplegia. / Clin Neuro- ophthalmol 1987; 7: 165- 6. 8. Poser CM, Paty DW, Scheinberg L, et al. New diagnostic criteria for multiple sclerosis: guidelines for research protocols. Ann Neurol 1983; 13: 227- 31. / Neuro- Ophthalmol, Vol. 14, No. 1, 1994 |
