title: A method of measuring pupil-blocking force in the human eye.
abstract: A new method of measuring pupil-blocking force in the human eye is reported. The anterior segment of the eye was photographed using a slit-lamp apparatus and the color photographs then analyzed with a digitizer for converting the optical image of the anterior eye segment into the true image using a computer. This technique permits precise estimation of the relative positions of the anterior chamber, such as pupil margins, iris root insertions, and central anteroposterior pupillary axis. Pupil-blocking force was calculated from these data according to Hook's law. There was a statistically significant difference in pupil-blocking force between normal subjects (mean +/- SD, -0.027 +/- 0.029 lambda; lambda = Young's module) and patients with primary angle-closure glaucoma (mean +/- SD, +0.134 +/- 0.068 lambda) (P less than 0.001). In patients with primary angle-closure glaucoma, during an acute attack the pupil-blocking force was markedly high. This technique for measuring pupil-blocking force will provide valuable data for the analysis of the mechanism of primary angle-closure glaucoma.
authors: Department of Ophthalmology, Kobe City General Hospital, Japan.
authors: T
authors: T
authors: Kondo
authors: M
authors: M
authors: Miura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D005260:Female; D005901:Glaucoma / Q000209:etiology; D006801:Humans; D007499:Iris Diseases / Q000150:complications / Q000503:physiopathology; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D011680:Pupil; D012016:Reference Values