ABSTRACT
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.
Subject(s)
Contact Lenses, Hydrophilic , Presbyopia/therapy , Adult , Aged , Contrast Sensitivity/physiology , Eyeglasses , Humans , Middle Aged , Patient Satisfaction , Presbyopia/physiopathology , Surveys and Questionnaires , Vision, Ocular/physiology , Visual Acuity/physiologyABSTRACT
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.
Subject(s)
Contact Lenses , Presbyopia/therapy , Consumer Behavior , Contrast Sensitivity , Evaluation Studies as Topic , Female , Humans , Male , Middle Aged , Prognosis , Prospective Studies , Prosthesis Design , Visual AcuityABSTRACT
Keratoconus is an ectatic corneal disorder that results in a central or inferior conelike anterior protrusion. This results in irregular myopic astigmatism, causing considerable visual impairment. We have completed a retrospective clinical study of keratoconus in the central Kentucky area. When compared to other national studies of keratoconus, our study patients generally had more severe disease at the time of diagnosis and had a higher rate of keratoplasty. Keratoconus treatment is highly successful, and early diagnosis is warranted to prevent unnecessary visual loss.
Subject(s)
Corneal Transplantation , Keratoconus/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Kentucky , Male , Middle Aged , Retrospective StudiesABSTRACT
Corneal and aqueous levels of topically applied trifluorothymidine (F3T) were compared with and without the collagen shield in normal and damaged rabbit eyes. Shields were presoaked in 1% F3T for 15 minutes prior to application. Rabbits received either a presoaked shield, 1% F3T drops every two hours, or both. Corneal and aqueous levels of F3T were measured at 30 minutes, two, four, and eight hours. If 5 mm epithelial defects were created, the collagen shield and topical F3T drops produced significantly higher levels of F3T than drops alone at all periods tested (P less than .05). A presoaked shield alone produced greater levels of F3T than drops alone at 30 minutes and two hours (P less than .05). Collagen shields did not enhance F3T levels in eyes with intact epithelium. Implications for treatment of herpetic keratouveitis are discussed.
