In biometric photographs of 13 patients, we quantified the iris contour in eyes with central anterior chamber depths ranging from 1.9 to 3.4 mm (epithelium to lens surface). This actual profile was compared to that predicted by a theoretical analysis of the forces acting on the iris. The average discrepancy between the calculated actual and the theoretically predicted iris position was only -0.01 to +0.03 mm. The close agreement validates the model under normal conditions and in the presence of relative (nonsynechial) pupillary block. The theoretical iris shape may not occur under conditions that violate the underlying physical assumptions of the mathematical model, such as when iridectomy eliminates the pressure difference between the anterior and posterior chamber or when synechiae introduce additional forces on the iris other than the ones included in the analysis.
Bibliographical noteFunding Information:
From the Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, Florida. This study was supported in part by National Glaucoma Research, a program of American Health Assistance Foundation, Rockville, Maryland and by the U.S. Public Health Service core center grant P30-EY-02180 and National Research Service Award T32-EY-07021 from the National Institutes of Health.