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Purpose: To evaluate visual outcome and corneal shape change during the first month of wearing corneal refractive therapy (CRT) reshaping contact lenses to correct myopia in otherwise healthy eyes., Methods: Twenty-nine eyes were fit with Paragon CRT contact lenses, which were worn nightly. Before and after CRT fitting, uncorrected visual acuity was measured, and corneal topography was performed and evaluated with the Holladay Diagnostic Summary EyeSys 2000 Videokeratoscope. To evaluate the visual outcome, refractive yield (achieved/attempted correction) was calculated and accounted for distance or monovision., Results: Uncorrected visual acuity improved in all patients. In 1 month, refractive yield was 96.7%. Corneal uniformity index and predicted corneal acuity index were maintained, and the Q value changed from -0.08 to +0.38 (P < 0.05)., Conclusions: CRT lenses are effective in improving visual acuity. They significantly changed the corneal from prolate to oblate while maintaining corneal quality.

Purpose: A direct mail survey of residents and young practitioners in ophthalmology was undertaken to assess the extent and effectiveness of residency training relating to contact lenses., Methods: The respondents, 135 residents and 124 young practitioners, represented 117 of the 128 residency programs in the United States. The questionnaire dealt with issues including respondents' sources of information about contact lenses during and after residency, the residency years in which they received contact lens training, the frequency and length of clinic sessions dealing with contact lenses, the number and types of patients they saw, and the number and training of their clinic supervisors. In addition, the questionnaire elicited respondents' ratings of their total residency programs and their specific training with regard to contact lenses and their degree of confidence in dealing with lens-related problems., Conclusions: The results of this survey indicate that residency programs take no consistent approach to contact lens training and are not adequately preparing ophthalmologists to deal with the fitting and management of contact lenses or problems relating to their wear.

We evaluated a new integrated contact lens care system that combines fluid turbulence for lens cleaning with ultraviolet (UV) light for solution sterilization. The ultraviolet light system was used to clean and disinfect 42 soft contact lenses (water contents: 38.6%, 43%, 55%, and 70%) and two rigid gas permeable lenses. Test lenses were contaminated with 10(6) cells/mL of Bacillus pumilus, Aspergillus niger, Pseudomonas aeruginosa, and Acanthamoeba castellanii and subjected to a 15-minute cleaning-disinfection cycle. Bathing solutions and contact lenses were cultured at various time intervals and at the end of the cycle. All bathing solutions and all lenses but one were found to be sterile after one cycle. All units effectively disinfected solutions and contact lenses. This device may be an effective alternative to existing contact lens care systems.

The intraocular pressure (IOP) of nine cadaver eyes was set by a manometer at 10 mm Hg increments from 10 to 50 mm Hg. Pressure measurements at each of these settings were taken using the Digilab Pneumatonometer and Tono-Pen to determine the accuracy of these instruments. In addition, four brands of therapeutic contact lenses were placed on the eyes, and IOPs were measured through them to determine whether or not comparable IOPs could be obtained through a range of bandage contact lenses. We found a significant difference (p < or = 0.0000) between the measurements obtained by the two instruments at a given manometric setting. Digilab Pneumatonometer's pressures correlated well with manometric pressures. Tono-Pen consistently underestimated manometric pressures. At 50 mm Hg, Digilab Pneumatonometer's mean measurement was 47.5 mm Hg, whereas Tono-Pen's mean was only 38.9 mm Hg. IOPs assessed through all contact lenses were comparable to the measurements without lenses. Multiple regression of score showed that the measured pressure was explained by manometric pressure (81%), the choice of instrument used (5.5%), and the lens thickness (0.09%). The Pierson correlation coefficient was 0.93. This study showed that Pneumatonometer could accurately measure IOP with and without a therapeutic contact lens, but Tono-Pen was equally inaccurate with and without lenses, giving false low measurements.

We conducted a retrospective assessment of the fitting characteristics obtained with the Boston Envision rigid gas permeable contact lens to determine the best parameter for selecting an initial base curve. We fit 13 subjects (11 successfully) with the Envision lens, using computerized videokeratoscopy to evaluate prefitting corneal topography. The selected base curve of the lenses fit most closely to the flattest K at the 5 mm zone. This value may be the best parameter for selection of an initial base curve, especially in eyes with keratoconus. Using topographic information may give quicker and more accurate initial fits than keratometry alone.

It has been difficult to document the subjective complaint of glare. Devices to quantify this problem include the Miller-Nadler glare tester (MNGT) and the brightness acuity tester (BAT). We used these devices to evaluate a group of pseudophakic subjects (15 eyes with posterior-chamber intraocular lenses) and a group of normal subjects (32 low myopic eyes). A subject's ability to discern contrast with a background glare source is measured as a percentage with the MNGT. The number of lines lost on the Snellen chart as a light is brightened progressively over the line of vision is the BAT score. A Wilcoxon signed-ranks test showed no significant change without correction (SC) to with correction (CC) with the BAT but was significant at P less than .001 with the MNGT. The BAT scores for the normal group CC (mean, 0.59) compared with the intraocular lens group CC (mean, 3.0) with the Mann-Whitney U test showed a statistically significant difference (P less than .001). There also was a difference with the MNGT between normal group CC (mean, 5.1%) and pseudophakic group CC (mean, 8.9%) at P less than .001). These results suggest that pseudophakic subjects have marked visual dysfunction secondary to glare. The BAT, however, showed a more easily quantifiable change unaffected by spectacle correction.

The incidence of corneal infections among the almost 20 million Americans who wear contact lenses, while still small, is rising rapidly. Patient non-compliance with instructions for proper lens care is partly at fault. The general phenomenon of patient non-compliance has been widely studied, most often by using the Health Belief Model (HBM). We report here on 50 consecutive patients fit with contact lenses by one ophthalmologist who were questioned by telephone regarding their lens care practices and beliefs. Forty-four percent of this group wore contact lenses for therapeutic reasons; the remainder wore them for either cosmetic reasons (34%) or convenience (22%). Adherence to published lens care guidelines was used as a basis for segregating patients into a compliant and a non-compliant group. By the criteria selected, 46% of the sample was non-compliant in their lens care. An analysis of responses from each group was structured in terms of HBM dimensions. Our aim was to determine whether there were differences in the beliefs held by compliant vs. non-compliant patients. Age under 30 and obtaining lenses for cosmetic or convenience reasons were the two variables statistically associated with non-compliant behavior. At least one undesirable belief representing each of the four HBM dimensions was found to be positively correlated with non-compliant lens use. The HBM is an effective model with which to investigate the relationship between non-compliant behavior and the rise in contact lens-related complications.