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Show Journal of Neuro- Ophthalmology 16( 1): 7- 8, 1996. 1996 Lippincott- Raven Publishers, Philadelphia Feature Photo Anterior Ischemic Optic Neuropathy Associated with Disc Drusen William D. Newman, M. R. c. ophth., and E. David Dorrell, F. R. C. S., F. R. c. ophth. Anterior ischemic optic neuropathy ( AION) is a condition more commonly found in later life. We present a case of unilateral AION in a 13- year- old boy with small discs and ipsilateral optic nerve head drusen. Key Words: Anterior ischemic optic neuropathy- Small optic disc- Optic disc drusen. A 13- year- old boy presented to the Ophthalmic Casualty Department ( Westbourne Eye Hospital, Westbourne, England) with blurred vision in the left eye. CASE REPORT The patient was emmetropic and had a visual acuity of 20/ 15 in both eyes. He had a left afferent pupil defect and complained that colours were not as bright with his left eye; arcuate defects were found on perimetry in the left visual field. Examination of the fundus revealed a small disc on the right with spontaneous venous pulsation. The left optic disc was pale and swollen with dilated capillaries, splinter hemorrhages ( Fig. 1), and no venous pulsation. There were no visible drusen nor From Westbourne Eye Hospital, Westbourne, Bournemouth, Dorset, England. Address correspondence and reprint requests to Mr. E. David Dorrell, Westbourne Eye Hospital, R. V. H.- Westbourne, Poole Road, Westbourne, Bournemouth, Dorset, BH4 9DG, England. FIG. 1. Left optic disc at presentation. 7 8 W. D. NEWMAN AND E. D. DORRELL FIG. 2. CT scan. any inflammatory activity within the vitreous. A computed tomography ( CT) scan revealed only bright deposits in the vicinity of the left optic disc ( Fig. 2); they were confirmed by ultrasound B- scan ( Fig. 3). Fluorescein angiography was performed 20 days after presentation. Autofluorescence was demonstrated in the left optic disc ( Fig. 4) before the dye was injected, and bright irregular spots were seen in the same position as the autofluorescence in the later pictures. However, in the later pictures, leakage of dye from the disc could not be found and the hemorrhages seen earlier had been reabsorbed. The clinical picture and test results indicated a diagnosis of anterior ischemic optic neuropathy ( AION) in a small disc containing drusen. The visual acuity remained unchanged during the fol- FIG. 3. B- scan of the left eye: log mode 36 dB. FIG. 4. Autofluorescence at the left optic disc. lowing year, but the visual field loss and the afferent pupil defect persisted. Venous pulsation on the left optic disc was noted 20 days after the disorder was first discovered. DISCUSSION Drusen of the optic disc have been extensively described in the literature; such discs can simulate papilledema and are often associated with field defects or hemorrhages on the disc or beneath the retina in the juxtapapillary area. True swelling, as opposed to elevation of the disc containing drusen, has been described by Beck et al. ( 1) and Gittinger et al. ( 2). Each group reported five cases of AION in discs with optic disc drusen in people younger than expected for this condition. AION is rare in children but Taylor et al. ( 3) found two cases in children with malignant hypertension. Spencer ( 4) commented that drusen occur in small discs and Beck et al. ( 5) reported a significantly greater number of discs with no cups in fellow eyes of a group with AION. The mechanical affect of drusen in the nerve head may give rise to damage to axons and also hinder perfusion, causing more acute ischemic swelling and field loss in a disc prone to the formation of drusen and AION by its small size. REFERENCES 1. Beck RW, Corbett JJ, Thompson HS, Sergott RC. Decreased visual acuity from optic disc drusen. Arch Ophthalmol 1985; 103: 1155- 9. 2. Gittinger JW, Lessell S, Bondar RL. Ischemic optic neuropathy associated with optic disc drusen. / Clin NeuroOphthal-mol 1984; 4: 79- 84. 3. Taylor D, Ramsey J, Day S, Dillon M. Infarction of the optic nerve head in children with accelerated hypertension. Br J Ophthalmol 1981; 65: 153- 60. 4. Spencer WH. Drusen of the optic disc and aberrant axo-plasmic transport. Am } Ophthalmol 1978; 85: 1- 12. 5. Beck RW, Servais GE, Hayreh SS. Anterior ischemic optic neuropathy: cup to disc ratio and its role in pathogenesis. Ophthalmology 1987; 94: 1503- 8. J Neuro- Ophthalmol, Vol 16, No. 1, 1996 [KBDdcadrusendiscswithcomplications] |