Contact lens fitting in keratoconus.
ABSTRACT The treatment of keratoconus can be implemented by the use of spectacle lenses, contact lenses of various kinds, and surgery. In this article, we deal with the procedures of contact lens fitting in patients diagnosed with keratoconus. The different types of specific contact lenses and the methodology of fitting these contact lenses for keratoconus are described. To select a contact lens for the individual patient depends upon the severity of keratoconus and the amount of corneal ectasia. Pending these criteria, a contact lens is chosen, which will give the best visual acuity and tolerance. At present, many designs of special contact lenses exist in oxygen-permeable materials; in addition, other systems, such as piggy-back, SoftPerm, semi-scleral, and scleral contact lens types are used. Contact lens fitting on a conical cornea will smooth out the highly irregular optical surface of the cornea and improve visual acuity considerably. Contact lenses are one of the better solutions to correct refractive errors induced by pathology, and they should be prescribed as soon as the keratoconus is detected to avoid development of amblyopia. The quality and quantity of vision is far better than with spectacle lens correction.
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ABSTRACT: Purpose. The purpose of this study is to evaluate the vision related quality of life in patients with keratoconus by using the National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25). Methods. Thirty patients presented with keratoconus (keratoconus group) and 30 healthy patients (control group) were included in this study. Twenty patients were using rigid gas permeable and 10 patients were not using contact lenses in keratoconus group. High and low contrast visual acuity and mean K values of the patients were recorded. Each subject completed the 25-item NEI-VFQ-25. Results. All subscales of NEI-VFQ-25 were lower in the keratoconus patients. The difference was more evident in the subscales of general vision, ocular pain, near vision, vision-specific mental health, vision-specific role difficulties, and peripheral vision . Overall composite score was 75.2 +/- 17.2 in the keratoconus group and 93.2 +/- 5.6 in the control group . Contact lens wearers had higher best corrected visual acuity in comparison with noncontact lens wearers . Patients with low visual acuity (logMAR > 0.4) in the better eye had lower distance vision, social functioning, mental health, and role difficulties. Meanwhile, patients with low visual acuity (logMAR > 0.4) in the worse eye had lower general health scores . Conclusions. Vision related quality of life was worse in keratoconus patients. Success in the contact lens usage and maintaining higher visual acuity may improve vision related quality of life.Journal of Ophthalmology 04/2014; 2014. · 1.37 Impact Factor
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ABSTRACT: PURPOSE: To report the long-term refractive and optical quality outcomes of patients with intrastromal corneal ring segments (ICRS) to treat keratoconus and to analyze the results according to the patients' age. SETTING: Vissum Instituto Oftalmologico de Alicante, Alicante, Spain. DESIGN: Case series. METHODS: The uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, corneal topography, and aberrometry were evaluated before and after ICRS implantation in eyes with keratoconus. The follow-up was 5 years in all cases. RESULTS: The study comprised 51 eyes (35 patients; age range 15 to 56 years). After 6 months, the improvement in the UDVA, CDVA, spherical equivalent, and mean keratometry (K) value was statistically significant (P<.05). Five years postoperatively, these parameters remained unchanged (P=.31). Slight regression (0.97 diopter [D]) was observed in the mean K between 6 months and 5 years; the regression was not statistically significant (P=.39). Anterior corneal aberrometric values decreased; however, the changes were not statistically significant (P≥.10). Linear regression analysis showed no correlation between the age of the patients and the changes observed in the mean K throughout the follow-up (P>.05, r(2) = 0.001). CONCLUSIONS: Intrastromal corneal ring segment implantation in keratoconus patients provided long-term improvement of the refractive and topographic status. There was no correlation between the amount of individual changes in the mean K reading and patient age. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.Journal of Cataract and Refractive Surgery 06/2013; · 2.75 Impact Factor
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ABSTRACT: OBJECTIVES: To evaluate the utility of the Rose K2 XL semi-scleral contact lens (Menicon Co. Ltd., Nagoya, Japan) in the management of the irregular cornea. METHODS: Twenty-seven subjects (34 eyes) with irregular corneas referred for contact lens fitting were evaluated. A diagnostic trial set was used in the fitting process. Once the trial lens was considered optimal, a final lens was ordered from the manufacturer with the necessary changes in power, edge lift and diameter. We analyzed visual acuity, number of lenses ordered and patients' ability to wear and handle lenses. RESULTS: Twenty-three subjects (30 eyes) were fitted with the Rose K2 XL lens. Four subjects (4 eyes) decided not to conclude the fitting process for different reasons. Average logMAR visual acuity without correction and with the lens was 0.82 and 0.09, respectively (p<0.001). An average of 1.4 ordered lenses (range 1-3) were necessary to achieve the optimal fit. Nineteen eyes (63%) were fitted with the first lens ordered. Three subjects (13%) had problems with lens handling, and three subjects (4 eyes) abandoned the wear of the lenses after three months due to discomfort (3 eyes) and unsatisfactory visual acuity (1 eye), respectively. Follow-up ranged from 6 to 9 months. CONCLUSION: Rose K2 XL semi-scleral contact lens provides good visual acuity and comfort in patients with irregular corneas.Contact lens & anterior eye: the journal of the British Contact Lens Association 01/2013;