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Show Literature Abstracts (Reprint requests to P. S. O'Connor, M.D., Department of Ophthalmology, University of Texas Health Science Center, San Antonio, TX 78284.] A time-honored caveat in the characterization of glaucomatous visual loss is that papillomacular fibers are normally spared, leaving acuity intact until the late stages. This caveat is disputed effectively by Pickett et at. in their presentation of 10 patients with monocular decrease in visual acuity and asymmetric glaucomatous loss. Eight of the patients had visual field defects in the contralateral eye, and all but one had documented pressures of at least the low 20s. A variety of ancillary tests-CT, skull radiographs, FTA-ABS, sedimentation rate, noninvasive carotid studies-were done, but only in certain patients, and one presumes that history-taking precluded other diagnoses (e.g., shock-induced optic neuropathy). These patients are seen not infrequently in neuroophthalmic referral, and the authors are not overemphatic when they conclude that "this is a relatively rare finding in glaucoma, and other possible etiologies of optic disc cupping and central visual field defects should be ruled out, with special attention given to the possibility of compressive lesions." Lyn A. Sedwick, M.D. • • • Occipital Lobe Dysplasia. Tychsen, L. and Hoyt, W. F. Arch. Ophthalmol. 103: 680-682, 1985. (Reprint requests to Room M-876, University of California, San Francisco, CA 94143 (Dr. Hoyt).] Tychsen and Hoyt present two cases in which history and ocular findings are consistent with congenital left hemianopia. Computed tomography scan ~as normal in one ~ase, a~d in the other was suggestive of decreased tissue In the right occipital pole. 280 Magnetic resonance imaging demonstrated dysplasia of the right occipital lobe in both patients. As the authors note, this "represents a milestone in diagnostic cerebral imaging that will be extended in the future as methods improve." Lyn A. Sedwick, M.D. • • • Color Contrast Perimetry: The Spatial Distribution of Color Defects in Optic Nerve and Retinal Diseases. Hart, W. M., Jr. and Burde, R. M. Ophthalmology 92(6): 768-776, 1985. [Reprint requests to William M. Hart, Jr., M.D., Department of Ophthalmology, Washington University School of Medicine, 51. Louis, MO 63110.] Hart and Burde used color contrast perimetry and compared this to standard Goldmann perimetry and/or Octopus computerized perimetry (luminance contrast perimetry) in 28 patients with visual loss from optic nerve or retinal disease. As Dr. Joel Glaser notes in his cogent discussion following this paper, "(1) aU central field defects demonstrated by luminance contrast were also detected by color contrast testing; (2) no defects found by color contrast could not also be found by conventional automated (i.e., Octopus) perimetry; (3) Keillner's celebrated rule does not (again) stand up; and (4) optic neuropathies tend to depress color and luminance contrast sensitivity across the entire field, while retinal disease usually produces scotomatous holes." Dr. Glaser goes on to note that "the authors have demonstrated that their technique works but ... it is still not absolutely clear that Traquair's 1927 statement requires revision." Lyn A. Sedwick, M.D. • • • Journal of Clinical Neuro-ophthalmology |