Normal retina thickness11/3/2023 ![]() Glaucomatous (open angle) eyes had a measured IOP of 24 mm Hg or more on at least 2 occasions. Test eyes were classified as glaucomatous, OHT, or normal based on the following criteria. Informed consent was obtained from all participants and the methods were approved by the University of California San Diego Human Subjects Committee. All test eyes had a best-corrected visual acuity of at least 20/40. One eye of each subject was randomly selected for study. 81, respectively).Īll subjects had a complete ophthalmologic examination including direct and indirect ophthalmoscopy, intraocular pressure (IOP) measurement, stereoscopic photographs of the optic disc, and visual field testing prior to OCT image acquisition. Correlations were weak between age and RNFL thickness in the nasal and inferior quadrants ( r = −0.02, P =. 01), and a trend toward a significant correlation between age and RNFL thickness in the superior quadrant ( r = −0.23, P =. Subjects were age-matched because preliminary analysis of OCT data from 61 normal eyes (from patients aged 23-80 years mean age, 53.4 ± 14.6 years) revealed a significant correlation between age and RNFL thickness in the temporal quadrant ( r = −0.32, P =. Three age-matched groups, classified as ocular hypertensive (OHT) (n = 28), normal (n = 30), and glaucomatous (n = 29), were recruited from the Glaucoma Center of the University of California, San Diego. In this study, we assessed RNFL thickness in ocular hypertensive eyes using the commercially available Optical Coherence Tomograph (OCT 2000, software version A4X1 Humphrey Instruments, San Leandro, Calif). 8Īs there is considerable evidence that RNFL loss precedes visual field loss 11 - 14 and optic nerve head defects 15, 16 in patients with glaucoma, it is of interest to quantify this loss in patients with ocular hypertension who are at risk for developing glaucoma. 8 - 10 Finally, visual field loss correlated with RNFL thickness as determined by this OCT prototype in glaucomatous eyes. 7 Reproducibility studies using an OCT prototype have shown SDs of measurement of RNFL and retinal thicknesses of approximately 10 to 20 µm (10%-20%) in normal and glaucomatous eyes. 6 This instrument also performed well in detecting induced RNFL lesions in monkeys. 3, 5 With a prototype instrument, OCT data were reported to correlate with the known topography of human retinas. 2 - 4 Optical coherence tomography has been demonstrated to detect changes in tissue thickness with micrometer-scale sensitivity. 1 Early biological uses of this technology involved imaging of the human anterior chamber, peripapillary retina, and coronary artery. This technology was initially designed for fiberoptic use. OPTICAL COHERENCE tomography (OCT) is one promising technology that has been developed to assess tissue thickness in vivo, such as that of the retinal nerve fiber layer (RNFL). Retinal nerve fiber layer was significantly thinner in glaucomatous eyes than in ocular hypertensive and normal eyes throughout 360° and in all quadrants.Ĭonclusion These findings suggest that quantitative differences in RNFL thickness exist between age-matched ocular hypertensive, normal, and glaucomatous eyes. More specifically, RNFL was significantly thinner in ocular hypertensive eyes than in normal eyes in the inferior quadrant, 84.8 µm (75.6-94.0 µm) vs 107.6 µm (99.3-115.9 µm) and in the nasal quadrant, 44.1 µm (37.5-51.7 µm) vs 61.8 µm (53.0-65.6 µm). Results Mean (95% confidence interval) RNFL was significantly thinner in ocular hypertensive eyes than in normal eyes, 72.8 µm (66.4-78.1 µm) and 85.8 µm (80.2-91.7 µm), respectively. A single index of average RNFL thickness throughout 360° also was obtained. In each eye, average RNFL thickness measurements were obtained in temporal, superior, nasal, and inferior quadrants. Three circular scans were obtained for each eye at a diameter of 3.4 mm around the optic disc. Subject eyes were classified into diagnostic groups based on intraocular pressure, stereoscopic disc photographs, and standard automated perimetry. Methods The mean RNFL thickness of ocular hypertensive (n = 28) eyes was compared with age-matched normal (n = 30) and glaucomatous (n = 29) eyes. Objective To quantitatively assess and compare the thickness of the retinal nerve fiber layer (RNFL) in ocular hypertensive eyes with normal and glaucomatous eyes using the Optical Coherence Tomograph (OCT 2000, software version A4X1 Humphrey Instruments, San Leandro, Calif). Shared Decision Making and Communication.Scientific Discovery and the Future of Medicine.Health Care Economics, Insurance, Payment.Clinical Implications of Basic Neuroscience.Challenges in Clinical Electrocardiography.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |