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Light Scatter Causes the Grayness of Detached Retinas
Implications for Vision Loss in Retinal Detachment
Shizhuo Yin, PhD;
Thomas W. Gardner, MD, MS;
Tanu O. Thomas, MD;
Keith Kolanda, COT
Arch Ophthalmol. 2003;121:1002-1008.
Objective To investigate the cause of the gray appearance of the detached retina.
Methods The effects of ex vivo bovine retinas and Scotch (3M, Minneapolis, Minn) tape on light scattering were predicted based on mathematical modeling and examined empirically on an optical bench. Images were collected with a CCD [charged-coupling device] camera connected to a microcomputer with an image grabber. The clarity of the image was calculated as the standard deviation,  .
Results Calculations predicted a gaussian distribution of laser light scattering with increased diffusion with increasing distance from the medium to the target. The image clarity, , increased rapidly in the first 50 µm of separation of the retina and tape from the test target and the rate of increase diminished thereafter. Removal of the outer retina with an excimer laser improved retinal transparency.
Conclusions Data explain that the gray appearance of the detached retina results from light scattering. This phenomenon likely results, at least in part, because of the irregular outer retinal surface at the level of the photoreceptors.
Clinical Relevance The findings suggest that visual loss in retinal detachment may result, in part, from optical properties of the detached retina and have implications for visual recovery and subretinal surgery.
From the Department of Electrical Engineering, Pennsylvania State University, University Park (Dr Yin); Departments of Ophthalmology and Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey (Drs Gardner and Thomas); and the Memorial Eye Institute, Harrisburg, Pa (Mr Kolanda). The authors have no relevant financial interest in this article.
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