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Show 14. Reference: Sadun, A. A, and Le~.,ell, S.: Brightness- sense and optic nerve disease. Arch. Ophthalmol. 103: 39-43, 1985. Reprints: A A Sadun, M.D., Ph.D., Department of Ophthalmology, University of Southern California, School of Medicine, Estelle Doheny Eye Institute, 1355 San Pablo St., Los Angeles, CA 90033. A "new" test for optic nerve dysfunction is described that subjectively tests the patient's sense of "brightness" binocularly using a glossy photograph of a white disc on a black background. A pair of polarized filters was rotated monocularly to equalize perceived brightness of this target. The test was used on 29 normal subjects, 13 patients with factitious visual loss, 5 patients with unilateral maculopathy, 4 with monocular cataract, and approximately 50 patients with optic neuropathy, monocular or binocular. Data are presented fully and clearly for patients with optic neuritis; many patients demonstrated an interesting persistence of reduction in brightness sense while showing resolution of color and acuity problems as well as a relative afferent pupillary defect. Data comparing normal subjects and optic neuritis, cataract, maculopathy, and factitiousloss patients are summarized in a slightly confusing table. Taken alone, these data seem to confirm that normal subjects and cataract patients have no intereye differences in brightness whereas all others do to a greater or lesser extent. The authors further refine this information by observing that patients with organic visual disorders consistently gave the same response, but those with factitious loss tended to vary their responses with repeated testing for brightness. They conclude that this is an easy, rapid test for monitoring optic nerve dysfunction and may be helpful in detection of malingering as well. In a less quantitative fashion, one probably gathers similar data when inquiring about the brightness of the testing light while performing the "swinging flashlight test" for a relative afferent pupillary defect. Lyn A. Sedwick, M.D. • • • 15. Reference: O'Keefe, M., Morley, K. D., Haining, W. M., and Smith, A.: Penicillamine-induced ocular myasthenia gravis. Am. J. Ophthalmol. 99: 66-67, 1985. Reprints: K. D. Morley, F.R.C.A.P., Department of Medicine, Ninewells Hospital and Medical School, Dundee 002 lUB, Scotland. Two patients with rheumatoid arthritis who were treated with penicillamine developed ocular myasthenia gravis that eventually resolved with cessation of penicillamine therapy. Both patients underwent histocompatability testing that showed HLADR1. The authors cite studies that show that patients with nonpenicillamine-induced myasthenia gravis have a HLA-DR3 in a 50% frequency. Also in a previous report on four patients with myasthenia induced by penicillamine, three had HLA-DR1 and one a HLA-DR3. The authors conclude that these patients with penicillamine-induced myasthenia have a ge- September 1985 Literature Abstracts netic background different from those of patients with idiopathic myasthenia gravis. This conclusion seems to be unwarranted, not only because of the small sample size but also because even by using the very report to which the authors refer, which shows a 50% incidence of DR3 with idiopathic myasthenia gravis, one notes that rheumatoid arthritis patients should have a similarly strong (50%) association with a specific 0 group, namely DR4, which neither of the two reported patients had. Lyn A. Sedwick, M.D. • • • 16. Reference: Trobe, J. D.: Isolated pupil-sparing third nerve palsy. Ophthalmology 92: 58-61, 1985. Reprints: J. D. Trobe, M.D., Department of Ophthalmology, College of Medicine, University of Florida, Box J-284, JHMHC, Gainesville, FL 32610. In an excellent effort to make diagnostic sense out of disturbing recent literature about "pupilsparing" third-nerve palsies in association with internal carotid and posterior communicating artery aneurysm, Dr. Trobe has devised three new categories into which to place patients for appropriate workup. Group 1 patients have a normal pupil but otherwise complete third-nerve palsy and do not need arteriography if they are over the age of 50; group 2 patients have a normal pupil with incomplete thirdnerve palsy and need arteriography, especially if the inferior division of the third nerve is spared; group 3 patients have partial pupil involvement with otherwise complete third-nerve palsy and need arteriography if a vasculopathic etiology (i.e., diabetes or hypertension) seems unlikely. The studies on which these categories are based are generally either retrospective reviews of neurosurgical charts, an informal survey of neurosurgical memory, or individual case reports. Although the small percentages of neurosurgical patients who have "pupil-sparing" thirdnerve palsies associated with an aneurysm seem irrefutable, the practicing ophthalmologist, neuroophthalmologist, and neurologist are left wondering whether slightly different overall percentages would be forthcoming from a nonneurosurgical review of isolated third-nerve palsies as, in many cases, referral to a neurosurgeon indicates that signs or symptoms of subarachnoid hemorrhage are present in addition to third-nerve palsy. Nevertheless, the message of this terse report is clear: Not every patient with an aneurysm will "blow" his pupil and arteriography should be considered case by case, pupil involvement or no. Lyn A. Sedwick, M.D. • • • 17. Reference: Feldon, S. E., Lee, C. P., Muramatsu, S. K., and Weiner, J. M.: Quantitative computed tomography of Graves' ophthalmopathy. Arch. Ophthalmol. 103: 213-215, 1985. Reprints: S. E. Feldon, M.D., Estelle Doheny Eye 203 |