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Show ! Olmw[ o( Ch,""," Nellro- oplttltallllo[ ogy 11( 3): 181- 182. 1991. If;, 1991 Raven Press, Ltd., New York Editorial Comment: Papillopathies Associated with Calcification In the Retrolaminar Optic Nerve Dr. Sadun and his colleagues report the cases of three patients with optic disc swelling and peripapillary hemorrhages who by standard echography were found to have calcified nodules within the optic nerves. Unlike optic nerve drusen, which are located anterior to the lamina cribrosa ( even when " buried"), the lesions detected by Sadun et a1. were posterior to the lamina. The authors suggest that the calcifications may be thrombi within the central retinal artery or vein and that these lesions may be responsible for the papillopathy. We have seen a case at the Wilmer Institute that possibly supports this conclusion. A 33- year- old healthy woman was referred to us with a 3- year history of transient loss of vision in the left eye only. The patient had first experienced the episodes beginning 2 weeks after the birth of her third child and had subsequently experienced hundreds of episodes without any permanent visualloss. Each episode lasted about 30 seconds or less and occurred at various times of the day, regardless of activity or posture. They did not develop when the patient looked in a particular position of gaze, but they seemed to resolve as soon as she moved her eye. During an episode, the patient could still see well enough to read, but the entire field of vision became gray, and colors seemed to fade. Before being examined by us, she had undergone multiple studies, including fluorescein angiography, CT scanning with orbital views, lumbar puncture, oculoplethysmography, and testing of visual evoked responses. These studies all gave normal results. When examined by us, the patient had a normal examination except that both optic discs were somewhat small, with no significant cupping ( Fig. 1). The patient experienced an episode of visual loss during the examination, during which time the visual acuity remained 20/ 20 in the left eye, but there developed a mild left relative afferent pupillary defect associated with mild red desaturation in the left eye. The attack resolved before we could examine the ocular fundus. Ultrasound examination revealed a moderately 181 large, calcified lesion within the substance of the left optic nerve just posterior to the lamina cribrosa ( Figs. 2- 4). We postulated that the lesion was a calcified thrombus of the central retinal artery or vein that was producing intermittent vascular obstruction affecting the function of the optic nerve, retina, or both. The patients reported by Sadun et a1. and the patient seen by us suggest that there may be some patients who, for reasons that are unclear, develop calcified lesions ( thrombi?) in the retrolaminar portion of the optic nerve that may cause transient or permanent visual loss, in some cases associated with optic disc swelling. The true nature of these lesions remains to be elucidated, as does the mechanism by which they produce visual symptoms and signs. It is possible that color- coded Doppler flow studies may be of help in addressing these issues. Neil R. Miller, M. D. Andrew P. Schachal, M. D. Culver Boldt, M. D. Baltimore, Maryland I FIG. 1. Photograph of the left optic disc shows a small, somewhat anomalous disc with no significant cup. 182 FIG. 2- 4. B- scan ultrasonography of the left optic nerve shows a small, calcified lesion in the immediate retrolaminar portion of the nerve. The calcified nature of the lesion becomes increasingly evident as the gain is decreased from Fig. 2 through Fig. 4. EDITORIAL COMMENT os |