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PURPOSE: Evaluate the ZEBRA 2000 (Z-10) bifocal contact lens on presbyopic and aphakic patients. METHODS: Thirty-eight patients, 37 presbyopes and one aphake, were fit in the Z-10 and evaluated for 6 months. RESULTS: Twenty patients (53%) completed 6 months of contact lens wear. Ten (26%) discontinued due to lens related problems, three (8%) discontinued due to other health problems, and five (13%) were lost to follow-up. Average refits per eye were 1.75. Average distance visual acuity was 20/25; average near visual acuity was J1.6; average wear time, 11 hours. Patient satisfaction was rated good in comfort and vision and fair in nighttime glare by patients' subjective evaluation. CONCLUSIONS: The ZEBRA 2000 (Z-10) can be a useful addition in fitting the general presbyopic patient population.

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PURPOSE: We performed a qualitative and quantitative assessment of contact lens performance at 1 and 6 months among 24 patients enrolled in the Piggyback Bifocal Contact Lens Study. METHODS: We fit 24 presbyopic patients with the Piggyback Bifocal Contact Lens System (i.e., a plano soft lens with a 9.4 mm cutout portion on which a bifocal RGP lens rides or "piggybacks"). Patients were evaluated prior to inclusion in the study and then at one month and six months after obtaining their lenses. Evaluations included slit lamp examination, evaluation of visual acuity at near and distance, and subjective rating of the patients' comfort. RESULTS: At one month, 61% of patients had Snellen acuities of 20/30 or better, 79% had near acuities of J2 or better, and 60% rated their comfort as good or very good. At six months, 100% of patients had Snellen acuities of 20/30 or better, 90% had near acuities of J2 or better, and 86% of patients rated their comfort as good or better. Twelve patients did not complete the study due to their decision to drop the study. CONCLUSIONS: The Piggyback Bifocal Contact Lens System is a well-tolerated, satisfactory means of optical correction for the motivated presbyope.

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PURPOSE: We prospectively evaluated the NOVAWET-Perception multifocal contact lens for comfort and performance. METHODS: We fit 28 presbyopic patients with this multifocal contact lens. This multifocal rigid gas permeable lens has a multiaspheric back surface and multiple eccentricity values, allowing for a natural field of vision at all angles. Patients were evaluated prior to inclusion in the study and then at 1,3, and 9 months. Evaluations included slit lamp examination, visual acuity, contrast sensitivity, and completion of a questionnaire regarding comfort and overall satisfaction. RESULTS: At the end of the study, 14 of 28 patients (50%) were successfully wearing the NOVAWET-Perception lenses. Of these, 12 (86%) achieved J2 or better near vision and 13 (93%) achieved 20/25 or better distance vision. Fourteen patients failed to complete the study. CONCLUSIONS: We believe the NOVALENS multifocal contact lens is a viable option for the correction of many presbyopic patients.

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We fit the SimulVue bifocal contact lens, a soft lens with a simultaneous vision design, in 30 presbyopic patients. The lens has a central near correction surrounded by a concentric peripheral distance correction. Patients were evaluated prior to inclusion in the study and followed for a period of 1 year. The evaluation included visual acuity and contrast sensitivity at both distance and near with and without lenses. In addition, patients completed a questionnaire at the end of the study. At the end of 1 year, 16 of 30 (53%) patients were successfully wearing the contact lenses. Of these, 13 of 16 patients (81%) achieved J2 or better near vision, and 10 of 16 (63%) achieved 20/25 or better distance vision in both eyes. Greater reduction of contrast sensitivity occurred at near, with only 38% of patients (6/16) retaining their normal contrast sensitivity; whereas at distance, 81% of patients (13/16) retained normal contrast sensitivity. Fourteen patients failed to complete the study. The most common reasons cited were poor vision at distance (6/14, 43%), poor vision at near (6/14, 43%), and ghosting of images (4/14, 29%). We believe that the SimulVue contact lens is a viable option for the correction of many presbyopic patients.

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We performed qualitative and quantitative assessments of contact lens performance at 1 and 6 months among 23 patients enrolled in the Solitaire Bifocal Contact Lens Study. Overall satisfaction and comfort at 6 months was rated good to excellent in 83% and 84% of patients, respectively. Daytime acuity at distance and near were rated very good to excellent in 75% and 83% of subjects. Quantitative measurements of distance and near acuities at 1 month revealed 83% and 88% of subjects, respectively, seeing better than or equal to 20/25 or J1. At 6 months there was a moderate decrease in the measured distance acuity. A disparity in glare disability was noted, with 53% of subjects indicating significant glare problems but only 21% of glare tested patients having acuities worse than 20/40. Attrition from the study was highest in the first month and was more common among first-time contact lens users. Overall, this segmented bifocal contact lens is well-tolerated and provides good distance and near vision for presbyopic patients.

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We conducted a study of 25 post-penetrating keratoplasty (PK) patients (28 eyes) fit with Quintasphere PK rigid gas permeable contact lenses. Using the Quintasphere PK trial set, 96% of patients were successfully wearing the lens at 6 months; at 1 year 93% were successfully wearing the lens. Eighty-two percent of eyes fit achieved at least 20/40 visual acuity, and 93% achieved at least 20/50. The average number of lenses fit per eye was 1.29. The design basis of the Quintasphere PK lens was predicated on a plateau-shaped corneal graft.

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We evaluated the distance and near vision of 33 presbyopic patients who wore the Anterior Constant Focus (ACF) rigid gas permeable (RGP) bifocal lens. Twenty-seven patients (82%) wore the lenses for one year; the six patients who quit the study complained of unacceptable vision (four patients) and discomfort (two patients). Twenty-five patients (76%) obtained 20/25 or better distance vision, and 28 patients (85%) obtained J2 or better near vision. Contrast sensitivity was within normal limits in 24 of 33 (73%) patients. We feel the ACF lens provides good bifocal vision in a non-translating RGP design.

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We fit two multifocal soft contact lenses, Bausch & Lomb's Bi-Tech and the Unilens contact lens from Unilens Corporation, in two separate populations of presbyopes. Most patients (24/42, 57%) had no prior contact lens experience. Patients were evaluated at 6 and 12 months for comfort, visual acuity, lens fit, and corneal findings. Both distance and near vision were found to be slightly decreased with each contact lens when compared to best corrected visual acuity with spectacles. Seventy-seven percent (14/18) of the Unilens wearers and 67% (16/24) of the Bi-Tech wearers continued to wear their lenses for at least 1 year. Those who discontinued lens wear did so because they were dissatisfied with their vision. Presbyopes who seek correction with soft contact lenses appear to be more tolerant of a decrease in distance vision than a decrease in near vision. Both lenses were comfortable and no corneal pathology was induced. Our results suggest that the Unilens (simultaneous vision design) provides more predictable correction of presbyopic symptoms than the Bi-Tech (alternating vision design) because it is independent of lower lid position and translation. Both of these lenses are viable options for the correction of presbyopic symptoms.

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To evaluate the efficacy of multifocal contact lenses in the correction of presbyopic symptoms we fit six young monocular aphakic patients with four different bifocal contact lenses (ACC, Tangent Streak, VFL, and Constavu). Each patient had 20/20 uncorrected vision and normal accommodation in the other eye. We evaluated both subjective and objective parameters of comfort and vision for all four lenses. We found no significant overall performance advantage among the four lenses based on comfort, visual satisfaction, visual acuity, contrast sensitivity, or wear-related corneal complications.

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The Tangent Streak trifocal is a rigid gas permeable contact lens with horizontal segments for distance, intermediate, and near correction. We undertook a prospective clinical evaluation of the Tangent Streak trifocal to determine the efficacy of this lens in correcting presbyopic symptoms. Distance, intermediate, and near corrections were compared using visual acuity and contrast sensitivity charts in 25 presbyopic ametropes. Compared to the original bifocal correction, the Tangent Streak trifocal provided 21 of 25 of study patients (84%) with subjectively improved intermediate vision, while maintaining distance and near vision. Twelve of 16 dissatisified bifocal contact lens wearers (75%) were successfully fit with the Tangent Streak trifocal. This study shows that the Tangent Streak trifocal lens can effectively provide multifocal vision to presbyopic ametropes.

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Over a one-year period we evaluated subjective and objective factors associated with extended wear of Boston IV rigid gas permeable contact lenses. Patients wore the lens on an extended wear schedule, with removal at 2-week intervals for cleaning. We performed keratometry and endothelial cell counts and measured visual acuity, contrast sensitivity, refraction, and corneal thickness at the initial visit (with patients wearing their former glasses or soft or hard lenses) and again at 6 and 12 months (with patients wearing the Boston IV lens). Twenty-four of 31 patients (77%) completed the study. All measured parameters were checked for statistically significant change over time. Contrast sensitivity increased at all spatial frequencies tested, with the largest increments occurring at higher frequencies (P less than .001). The other parameters showed no significant changes (P greater than .05). Our data support the use of contrast sensitivity for qualitative assessment of visual function among contact lens wearers and suggest that contrast sensitivity testing may prove to be a more effective means of evaluating visual acuity in contact lens wearers over time than Snellen acuity.

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The ACC, Alges, and Tangent Streak bifocal contact lenses were fit in separate populations of presbyopic patients, some of whom had not previously worn contact lenses. Complete eye examinations were performed on fitting and at 6 and 12 months after fitting to determine how effectively the lenses corrected presbyopic symptoms. Patients were examined for subjective comfort, visual acuity, contrast sensitivity, and by slit lamp. Sixteen of the 24 ACC lens wearers (67%), 23 of 31 Alges lens wearers (74%), and 25 of 27 Tangent Streak lens wearers (93%) wore their lenses comfortably after 12 months. Nine of 18 failures (50%) were successfully refit in one of the other bifocal lenses. Most patients read 20/25 and J1 with contrast sensitivity in the normal range at distance and near. Twelve of 16 patients (75%) with no prior contact lens experience continued to wear the lenses at 12 months. We believe that bifocal contact lenses provide an acceptable alternative for the correction of presbyopia. Lens fitting requirements and patient selection are discussed.

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