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Byline: Nabanita. Barua, Chitra. Sitaraman, Sonu. Goel, Chandana. Chakraborti, Sonai. Mukherjee, Hemandra. Parashar Context: Analysis of diagnostic ability of macular ganglionic cell complex and retinal nerve fiber layer (RNFL) in [...]

* PURPOSE: To determine whether patients with primary open-angle glaucoma have an increase in size thresholds, prolongation of reaction times, and greater localization errors to random dot motion stimuli than normal subjects. * METHODS: Motion perimetry, a computer graphics method of visual field testing, quantitates a subject's ability to detect a correlated shift in position of dots within a defined circular area against a background of fixed dots. We measured motion thresholds, the smallest detectable circular dot motion target, at the Humphrey 24-2 test loci. By using the subject's light-pen responses to the location of the targets, we computed motion size threshold, reaction times, and localization errors (number of pixels from where the subject touched the monitor to the target center). With motion perimetry and conventional automated perimetry, we tested one eye in each of 25 patients with primary open-angle glaucoma and 25 age-matched control subjects. We then generated total deviation pointwise probability plots for the patients with primary open-angle glaucoma. * RESULTS: Patients with primary open-angle glaucoma had increased mean motion size threshold (P < .0001) and increased localization errors (P < .002), compared with the control subjects. With the probability plot analysis, there was good correlation of the visual field defects between the two perimetry tests. Additionally, motion perimetry identified nerve fiber bundle-like defects in 12 patients that were not detected with conventional automated perimetry. * CONCLUSIONS: Patients with primary open-angle glaucoma had abnormal motion perception with an increase in spatial localization error.

Glaucoma is an abnormal condition of elevated pressure within the eye. Glaucoma results in gradual loss of peripheral vision, followed later by loss of central vision and blindness due to atrophy of the optic nerve. One of the most frequently seen early signs of glaucoma is the development of paracentral scotomas, which are areas of decreased vision involving the central point of fixation of vision. Defects in the field of vision due to glaucoma are most often found in the superior rather than inferior half of the visual field. However, the inferior rather than the superior field of vision may be more affected in some patients who have both glaucoma and diabetes. A study was undertaken to determine the qualitative differences in visual field defects between 87 diabetic and 110 non-diabetic patients with glaucoma. Patients with retinal abnormalities were excluded from the study. Forty of the non-diabetic patients (36.4 percent) had vision defects mainly in the inferior field of vision, whereas 56 (64.4 percent) of the diabetic patients showed this pattern; the difference between groups was significant. It is suggested that a vascular (blood vessel-related) element, as may occur in diabetic patients, may influence the damage to the optic nerve from glaucoma. This could cause the different pattern of loss of visual field in diabetic patients. (Consumer Summary produced by Reliance Medical Information, Inc.)

Objective: To determine whether there is a difference in central corneal thickness between African American and Caucasian patients. If present, a difference might alter the measurement of intraocular pressure and potentially the assessment and management of glaucoma in these populations. Methods: Central corneal thickness was measured by means of ultrasound pachymetry in African American (n=56) and Caucasian (n=32) patients with suspected or confirmed glaucoma and control populations of African American (n=26) and Caucasian (n=51) subjects in whom there was no evidence of elevated intraocular pressure or glaucomatous optic nerve damage. Measurements of central corneal thickness were then compared between different subpopulations by means and population distribution analysis. Results: A statistically significant difference was noted between the mean ([+ or -] SD) central corneal thickness of all African American (including those with and without glaucoma) (right eye, 531.0 [+ or -] 36.3 [micro]m; left eye, 530.0 [+ or -] 34.6 [micro]m) and all Caucasian (including those with and without glaucoma) (right eye, 558.0 [+ or -] 34.5 [micro]m; left eye, 557.6 [+ or -] 34.5 [micro]m) patients. Similar results were found when subpopulations were tested. Distribution analysis of central corneal thickness measurements noted the largest cluster of African American patients around 520 to 540 [micro]m, whereas the largest cluster of Caucasian patients was between 580 and 600 [micro]m. Conclusions: African Americans were found to have thinner central cornea thickness measurements than Caucasians. This finding in African Americans may lead to lower applanation intraocular pressure readings compared with those of Caucasians, potentially resulting in an underestimation of the actual level of intraocular pressure. Arch Ophthalmol. 2001;119:23-27

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ajo.2007.01.031 Byline: Madeleine Zetterberg (a)(b), Gunnar Tasa (c), Mona Seibt Palmer (d), Erkki Juronen (c), Pait Teesalu (e), Kaj Blennow (d)(f), Henrik Zetterberg (d)(f) Abstract: To investigate apolipoprotein E (APOE) polymorphisms, which are known to influence the risk of Alzheimer disease (AD), in patients with primary open-angle glaucoma (POAG). Author Affiliation: (a) Institute of Neuroscience and Physiology, Department of Clinical Neuroscience and Rehabilitation, Section of Ophthalmology, The Sahlgrenska Academy at Goteborg University, Molndal, Sweden (b) Institute of Biomedicine, Department of Medical Chemistry and Cell Biology, The Sahlgrenska Academy at Goteborg University, Goteborg, Sweden (c) Department of Human Biology and Genetics, University of Tartu, Tartu, Estonia (d) Institute of Biomedicine, Department of Clinical Chemistry and Transfusion Medicine, The Sahlgrenska Academy at Goteborg University, Goteborg, Sweden (e) Department of Ophthalmology, University of Tartu, Tartu, Estonia (f) Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at Goteborg University, Molndal, Sweden. Article History: Accepted 17 January 2007