Stereoacuity and foveal fusion in adults with long-standing surgical monovision.

PURPOSE: Although binocular vision deficits occur in children who have a constant esotropia onset following significant maturation of stereopsis, it is uncertain whether adults are susceptible to changes to binocular vision. We examined binocular vision in adults with longstanding surgical monovision (> or =6 month's duration) to determine whether the binocular visual system remains susceptible to change. METHODS: Participants included 32 adults with longstanding monovision through laser-assisted in situ keratectomy or photorefractive keratectomy and 20 age-matched control subjects. After full binocular correction, binocular function was measured by using the Randot Stereoacuity Test, the Randot Preschool Stereoacuity Test, and the Worth 4-dot test at near and distance. Monovision patients were grouped as having low anisometropia (<1.5 spherical D) or moderate anisometropia (> or =1.5 spherical D). RESULTS: Non-parametric analysis of variance revealed a significant difference between group median stereoacuity (H = 16.062; P <.001). Pairwise multiple comparisons indicated both groups with monovision had significantly worse stereoacuity compared with control subjects (P <.05). Median stereoacuity values were 100 seconds of arc for patients with low anisometropia, 150 seconds of arc for patients with moderate anisometropia, and 40 seconds of arc for control subjects. A larger proportion of patients with moderate anisometropia failed the Worth-4 dot test at distance than control subjects (z = 2.619; P =.009). CONCLUSIONS: Reduced stereoacuity and an absence of foveal fusion in adults with longstanding surgical monovision suggest continued susceptibility of the binocular visual system to anomalous binocular experience.

The relationship between rod perimetric thresholds and full-field rod ERGs in retinitis pigmentosa.

Dark-adapted static perimetric fields and rod full-field electroretinograms (ERGs) were measured in normal subjects and 15 patients with retinitis pigmentosa. Psychophysical thresholds for short-wavelength stimuli were obtained from 76 locations across the retina on a modified Octopus 201 perimeter; threshold differences to short- and long-wavelength stimuli were used to determine whether rods were mediating threshold at each retinal location. Full-field rod ERG peak-to-peak amplitude as a function of retinal illuminance was analyzed by determining the parameters of the best-fit Naka-Rushton equation. Rod ERG thresholds and mean rod perimetric thresholds were significantly correlated with a slope of approximately 1.0. Log k was positively correlated with threshold elevation in the region of peak field sensitivity and log Vmax was positively correlated with log rod visual field area. These results demonstrate correspondence between parameters derived from rod visual fields and parameters derived from the Naka-Rushton analysis of the full-field rod ERG.

Management of the posterior capsule before and after the YAG laser.

A retrospective chart review of 2,514 consecutive posterior chamber implants was carried out to assess the management of the posterior capsule when vision loss dictated intervention. The capsulotomy technique used between May 1977 and March 1983 was pars plana posterior capsulotomy (227 eyes). All posterior capsulotomies performed after April 1, 1983 were with the YAG laser (342 eyes). Comparison of the complications with the two methods showed considerable differences. Anterior segment problems appear greater following YAG laser posterior capsulotomy than pars plana posterior capsulotomy, whereas posterior segment complications appear similar in both techniques. Comparison of CME following both techniques indicates that a delay of 6 months or more between cataract surgery and posterior capsulotomy is advisable.

Conjunctival autograft transplantation for unilateral ocular surface diseases.

Rehabilitation of the diseased ocular surface by autologous conjunctival transplantation as first described by Thoft has expanded the possibilities for eventual visual restoration of patients with severe ocular surface disease. This paper will introduce a new surgical technique for diseased ocular surface preparation and for the acquisition, transfer, and placement of a 360 degrees ring of autologous conjunctiva in patients with unilateral surface pathology. Patients representing different unilateral surface diseases with up to 2 years follow-up are presented and discussed.

Pupil capture: prevention and management.

Pupil capture occurs in a small percentage of patients following posterior chamber lens implantation. We noted a 3% incidence in 100 patients using sulcus fixated planar J-loop lenses, a 1% incidence using sulcus fixated angulated J-loop lenses, and a 1% incidence in capsular bag fixated flexible Y-loop lenses. No patients lost vision from pupil capture, and no clinically significant late complications were observed. Pupil capture may be successfully treated in the early postoperative period in some patients by mydriasis and a noninvasive loop compression technique using Q-tips.