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Karla Zadnik

Publications and source records attributed to Karla Zadnik.

At least 19 recordsLinked to original sources
PubMed2006

Baseline factors predictive of incident penetrating keratoplasty in keratoconus.

PURPOSE: To identify baseline demographic and clinical factors associated with undergoing penetrating keratoplasty (PK) in a prospective cohort of 1,065 keratoconus patients followed for eight years in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. DESIGN: Multicenter, prospective, observational cohort study. METHODS: We report the rate of PK over eight years and baseline factors predictive of PK in 1,065 patients who, at the time of study enrollment, had not undergone PK in either eye. RESULTS: Eighty-two percent of patients completed the eight-year close-out visit. Twelve percent (126 of 1,065) had PK in one (9.3%) or both eyes (2.5%). Baseline factors associated with increased likelihood of PK included younger age, steeper keratometric values, worse visual acuity, corneal scarring, poorer contact lens comfort, and poorer vision-related quality of life. The percent of eyes undergoing PK was 15% for patients 40 years old and younger, 28% for eyes with a steep keratometric value greater than 52 diopters, 33% for visual acuity less than 20/40, and 24% for eyes with corneal scarring. CONCLUSIONS: The CLEK Study confirmed previous reports of the increased likelihood of PK associated with corneal scarring, steeper keratometry values, poorer visual acuity, and poorer contact lens comfort. The CLEK Study is among the first to report an increased risk of PK associated with younger age, worse vision-related quality of life, and flatter contact lens fits. Knowledge of these factors is beneficial to clinicians in patient education and may be useful in disease management.

Adolescent↗
PubMed2006

Estimation of the incidence and factors predictive of corneal scarring in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study.

PURPOSE: The multicenter Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study is a prospective, observational study of 1209 keratoconus patients. We report methods to define incident corneal scarring and baseline factors predictive of incident corneal scarring in nonsurgical eyes of CLEK Study keratoconus patients through their fifth year of follow-up. METHODS: Of the 1,209 patients, 878 patients with at least one unscarred cornea at baseline were included in this study. The cumulative 5-year incidence of scarring is defined as the proportion of patients who developed central corneal opacification as detected by a clinician examining the patient with a slit-lamp biomicroscope and by masked readings of corneal photographs at the CLEK Photography Reading Center. Logistic regression analysis was used to test for relationships between baseline factors and incident corneal scarring. Baseline factors analyzed included age, sex, race, atopic disease, contact lens wear, family history of keratoconus, corneal curvature, and central corneal fluorescein staining, among others. RESULTS: The 5-year incidence of corneal scarring was 13.7% (120 of 878) overall, 16.7% (102 of 609) for contact lens-wearing eyes, and 38.0% (46 of 121) for contact lens-wearing eyes with corneal curvature greater than 52 D. Baseline factors predictive of incident scarring included corneal curvature greater than 52 D (odds ratio [OR] = 4.79; 95% confidence interval [CI], 3.08, 7.45; P < 0.001), contact lens wear (OR = 2.50; 95% CI, 1.40, 4.76; P = 0.003), marked corneal staining (OR = 2.38; 95% CI, 1.49, 3.76; P = 0.0002), and age less than 20 years (OR = 6.34; 95% CI, 2.57, 15.00; P < 0.0001). CONCLUSIONS: Multivariate analyses of 5-year prospective data from the CLEK Study cohort showed that baseline corneal curvature, contact lens wear, corneal staining, and younger age were predictive of the development of corneal scarring. The 5-year incidence of scarring is 13.7% for the overall sample and 38.0% for those eyes with corneal curvature greater than 52 D that wore contact lenses. Contact lens wear increased the risk of incident scarring more than 2-fold. These findings suggest a causal contribution of contact lens wear to corneal scarring in keratoconus and imply that corneal scarring might be reduced by modifying the contact lens fit.

Adult↗
PubMed2006

The Adolescent and Child Health Initiative to Encourage Vision Empowerment (ACHIEVE) study design and baseline data.

PURPOSE: The purpose of this study was to describe the baseline characteristics of subjects and methods for a multicenter, randomized clinical trial to compare the effects of contact lens wear and spectacle wear on children's self-perception. METHODS: Eligible subjects are randomly assigned to wear glasses or contact lenses throughout the 3-year study. Self-perceptions are measured 1 month after randomization and every 6 months using the Self-Perception Profile for Children (SPPC). Children's satisfaction with spectacles and refractive error-related visual quality of life are also measured using surveys developed for the study. Visual acuity, cycloplegic autorefraction, corneal curvature, and axial dimensions are measured annually. RESULTS: Five clinical sites enrolled 484 subjects with a mean (+/- standard deviation [SD]) age of 10.4 +/- 1.1 years. Approximately three-fifths of the subjects are girls, 47.1% of the subjects are white, 21.5% are black, and 21.5% are Hispanic. The mean (+/- SD) cycloplegic spherical equivalent autorefraction of the right eye is -2.38 +/- 1.04 D, and the average (+/- SD) axial length of the right eye is 24.32 +/- 0.77 mm. The average (+/- SD) Global Self-Worth score on the SPPC is 3.20 +/- 0.62 on a scale from one (low perceived competence) to 4 (high perceived competence). The average (+/- SD) spectacle satisfaction is 59.1 +/- 26.6 on a scale from zero (no satisfaction) to 100 (perfect satisfaction). The average refractive error-related quality of life score is 63.5 +/- 12.8 on a scale from zero (poor quality of life) to 100 (excellent quality of life). CONCLUSIONS: Subjects enrolling in the ACHIEVE Study are an ethnically diverse group of young myopic children. Ocular characteristics of the sample are consistent with data presented in other randomized clinical trials evaluating treatments for myopic children. The data reported here represent the baseline data for a 3-year randomized clinical trial to investigate the effects of contact lens vs. spectacle wear on children's self-perceptions.

Adolescent↗
PubMed2006

Comparison of multifocal and monovision soft contact lens corrections in patients with low-astigmatic presbyopia.

PURPOSE: The purpose of this study was to assess visual performance and patient satisfaction with two presbyopic soft contact lens modalities. METHODS: A crossover study of 38 patients with presbyopia was conducted. Patients were randomized first into either multifocal (Bausch & Lomb SofLens Multifocal) or monovision (SofLens 59) for 1 month. Visual performance was measured with high- and low-contrast visual acuity at distance and near and near stereoacuity. Patients' satisfaction was measured by the National Eye Institute Refractive Error Quality of Life Instrument questionnaire and by recording the patient's final lens preference. RESULTS: Patients maintained at least 20/20 binocular vision with both multifocal (MF) and monovision (MV) contact lenses under high-contrast conditions at distance and near. Under low-contrast conditions, patients lost less than a line of vision from the best spectacle correction to either multifocal or monovision contact lens correction at distance (pMF = 0.001, pMV = 0.006). Under low-contrast conditions at near, multifocal wearers lost five to six letters and monovision wearers lost two letters of vision (pMF < 0.001, pMV = 0.03, pMF/MV = 0.005). The average stereoacuity decreased by 79 s arc with monovision vs. multifocal contact lenses (p = 0.002). On the NEI-RQL, patients reported worse clarity of vision (pMF = 0.01, pMV < 0.001), more symptoms (pMF = 0.09, pMV = 0.01), and an improvement in their appearance with contact lens wear (pMF < 0.001, pMV < 0.001). Seventy-six percent of patients reported that they preferred multifocal contact lenses, and 24% preferred monovision contact lenses (p = 0.001). CONCLUSION: The majority of our patients preferred multifocals to monovision, most likely because the Bausch & Lomb SofLens Multifocal provides excellent visual acuity without compromising stereoacuity to the same degree as monovision.

Adult↗
PubMed2006

Comparison of the experience sampling method and questionnaires to assess visual activities in pre-teen and adolescent children.

AIM: A study was conducted to assess the feasibility of the experience sampling method (ESM) to quantify the daily visual tasks of children. METHODS: Thirty-one children (9-14 years old, 39% male) were randomly paged after school (four times per day) and on weekends (eight times per day) for seven consecutive days. When paged, the children completed a voicemail survey regarding the nature, duration, working distance and type of visual correction worn during the activity. Responses of the subjects were grouped into 14 categories. Before beginning the paging, each child and one parent also reported, via survey, the number of hours and working distance for several visual activities. RESULTS: The usable (complete voicemail responses) response rate was 87.1%. The most commonly reported activity category was watching television (17.8%). Other common responses included distance activities (12.5%), reading/studying (12.2%) and sports/outdoor activities (12.0%). Of the total number of responses, 25% were near work activities (reading/studying, computer use, near hobbies and playing Game Boy). The mean working distance (+/-S.D.) reported was 40.4 +/- 36.9 cm for reading/studying, 232.9 +/- 127.1 cm for watching television, 354.7 +/- 345.8 cm for distance activities and 438.5 +/- 421.0 cm for sports/outdoor activities. When comparing the ESM to surveys, the only significant difference was for the amount of time estimated to be spent in talking/conversation (p < 0.0001). No differences were found for any of the near work activities. CONCLUSIONS: The ESM provides a feasible way to quantify daily near work tasks in children.

Adolescent↗
PubMed2006

Longitudinal changes in visual acuity in keratoconus.

PURPOSE: The present investigation aimed to identify factors that predict reduced visual acuity in keratoconus from a prospective, longitudinal study. METHODS: This report from the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study used 7 years of follow-up data from 953 CLEK subjects who did not have penetrating keratoplasty in either eye at baseline and who provided enough data to compute the slope of the change over time in high- or low-contrast best-corrected visual acuity (BCVA). Outcome measures included these slopes and whether the number of letters correctly read decreased by 10 letters or more in at least one eye in 7 years. RESULTS: Mean age of the subjects at the first follow-up visit was 40.2 +/- 11.0 years (mean +/- SD). Overall, 44.4% were female, and 71.9% were white. The slope of the change in high- and low-contrast BCVA (-0.29 +/- 1.5 and -0.58 +/- 1.7 letters correct/year, respectively) translated into expected 7-year decreases of 2.03 high- and 4.06 low-contrast letters correct. High- and low-contrast visual acuity decreases of 10 or more letters correct occurred in 19.0% and 30.8% of subjects, respectively. Independent predictors of reduced high- and low-contrast BCVA included better baseline acuity, steeper first definite apical clearance lens (FDACL), and fundus abnormalities. Each diopter of steeper baseline FDACL predicted an increased deterioration of 0.49 high- and 0.63 low-contrast letters correct. CONCLUSIONS: CLEK Study subjects with keratoconus exhibited a slow but clear decrease in BCVA during follow-up, with low-contrast acuity deteriorating more rapidly than high-contrast. Better baseline BCVA, steeper FDACL, and fundus abnormalities were predictive of greater acuity loss with time.

Adult↗
PubMed2006

Accommodative lag before and after the onset of myopia.

PURPOSE: To evaluate accommodative lag before, during the year of, and after the onset of myopia in children who became myopic, compared with emmetropes. METHODS: The subjects were 568 children who became myopic (at least -0.75 D in each meridian) and 539 children who were emmetropic (between -0.25 D and +1.00 D in each meridian at all visits) participating between 1995 and 2003 in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study. Accommodative lag was measured annually with either a Canon R-1 (Canon USA., Lake Success, NY; no longer manufactured) or a Grand Seiko WR 5100-K (Grand Seiko Co., Hiroshima, Japan) autorefractor. Subjects wore their habitual refractive corrections while viewing a letter target accommodative stimulus of 4 D (either in a Badal system or at 25 cm from the subject, designated Badal and near, respectively) or of 2 D (Badal only). Refractive error was measured with the same autorefractor in subjects under cycloplegia. Accommodative lag in children who became myopic was compared to age-, gender-, and ethnicity-matched model estimates of emmetropic values for each annual visit from 5 years before, through 5 years after, the onset of myopia. RESULTS: In the sample as a whole, accommodative lag was not significantly different in children who became myopic compared with model estimates in emmetropes in any year before onset of myopia for either the 4-D or 2-D Badal stimulus. For the 4-D near target, there was only a greater amount of accommodative lag in children who became myopic compared with emmetropes 4 years before onset (difference, 0.22 D; P = 0.0002). Accommodative lag was not significantly elevated during the year of onset of myopia in any of the three measurement conditions (P < 0.82 for all three). A consistently higher lag was seen in children after the onset of their myopia (range, 0.13-0.56 D; P < 0.004 for all comparisons). These patterns were generally followed by each ethnic group, with Asian children typically showing the most, African-American and white children showing the least, and Hispanic children having intermediate accommodative lag. CONCLUSIONS: Substantive and consistent elevations in accommodative lag relative to model estimates of lag in emmetropes did not occur in children who became myopic before the onset of myopia or during the year of onset. Increased accommodative lag occurred in children after the onset of myopia. Elevated accommodative lag is unlikely to be a useful predictive factor for the onset of myopia. Increased hyperopic defocus from accommodative lag may be a consequence rather than a cause of myopia.

Accommodation, Ocular↗
PubMed2005

Differences in keratoconus as a function of gender.

PURPOSE: To characterize gender differences in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. DESIGN: Observational, longitudinal study. METHODS: A total of 1209 subjects at 16 clinics. For eye-specific categorical variables, the number of eyes per subject with the characteristic was counted. For eye-specific continuous variables, the mean of both eyes was calculated. Multivariate linear (for continuous outcomes) and logistic (for categorical outcomes) regression models were created for each baseline characteristic with statistically significant (P < or = .05) differences between men and women. Age, race, education, and corneal curvature were covariates. RESULTS: The women were older, more likely to report a family history of keratoconus, more likely to be nonwhite, and less likely to complete college than men. Vogt's striae and monocular and binocular high-contrast entrance acuity were the only visual characteristics that varied between men and women in the multivariate model. Women were more likely than men to report ocular symptoms of dryness and complaints based upon a composite score of ocular symptoms. Women reported more hours per day of near work and were less likely to report the ability to wear contact lenses for enough hours to permit reading at home in the evening. Women reported more visits to their eye care practitioner during the previous 12 months. NEI-VFQ results revealed differences in self-reported difficulty with distance activities and driving. CONCLUSIONS: Gender differences exist in patient history, vision, and ocular symptoms in keratoconus patients.

Adult↗
PubMed2005

Personality in keratoconus in a sample of patients derived from the internet.

PURPOSE: Keratoconus is a corneal disease that manifests itself in young adulthood and decreases vision. Anecdotally, keratoconus patients are commonly described as having unusual personality characteristics; however, previous researchers have not been able to define a unique keratoconus personality profile. We sought to better define the personality of patients with keratoconus. METHODS: The Millon Behavioral Health Inventory (MBHI) is a psychological instrument designed for use with physically ill patients to assess factors relevant to their medical care. The MBHI may aid in the evaluation of keratoconus patients and provide information relevant to the doctor-patient relationship. Patients with keratoconus were recruited through the World Wide Web. Surveys were conducted by mail, with all responses returned anonymously. One hundred fifty-three keratoconus patients were compared with the MBHI age-matched norms, generated from medical and nonmedical samples of adults. Subgroups of keratoconus patients were compared based on their self-reported rating of the daily burden of keratoconus. RESULTS: Keratoconus patients scored significantly lower (chi, P <0.05) compared with the normative population on the respectful coping style scale, and their scores were not significantly associated with a history of penetrating keratoplasty or their rating of the effect of keratoconus on their lives. This suggests that keratoconus patients are less respectful of practitioners, uncooperative, and noncompliant with treatment plans. Practitioners may look unfavorably on patients who exhibit these characteristics. This would also explain why the clinical perception of keratoconus patients persists, but other personality inventories have not defined a distinct keratoconus profile. CONCLUSIONS: These data from the MBHI, showing that keratoconus patients score lower on the respectful coping style scale, may explain eye care practitioners' perceptions about these patients' personality characteristics.

Adolescent↗
PubMed2005

Comparison of flat and steep rigid contact lens fitting methods in keratoconus.

PURPOSE: The purpose of this article is to compare the safety and efficacy of flat- and steep-fitting rigid contact lenses in keratoconus. METHODS: The Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study is a 16-center observational study. Cross-sectional results at baseline were generated for 1091 subjects with longitudinal results from the 871 subjects who completed 8 years of follow up. RESULTS: Of the 761 rigid contact lens-wearing patients at baseline, 41% had a scar at baseline compared with 24% of the nonrigid contact lens wearers (odds ratio [OR], 2.15; 95% confidence interval [CI], 1.35-3.43; p = 0.001). Eighty-seven percent were fitted with flat-fitting lenses, whereas 13% were fitted with steep-fitting lenses. Rigid lens fitting method was also associated with incident corneal scarring. A greater proportion of the corneas wearing flat-fitting contact lenses were scarred (43% compared with 26% for the steep-fitted eyes; OR,= 2.19; 95% CI, 1.37-3.51; p = 0.001). After controlling for corneal curvature, the association of rigid contact lens fit and corneal scarring at baseline did not persist (adjusted OR, 1.20; 95% CI, 0.70-2.06; p = 0.52). Thirty-two percent of unscarred eyes at baseline fitted flat had developed an incident corneal scar by the eighth year follow-up visit compared with 14% of eyes fitted steep (OR, 2.93; 95% CI, 1.34-6.42; p = 0.007). CONCLUSIONS: The data reported here indicate that, after controlling for disease severity in the form of corneal curvature, keratoconic eyes fitted with a rigid contact lens resulting in an apical touch fluorescein pattern did not have an increased risk of being scarred centrally at baseline. This "natural history" sample cannot determine causal proof that one method of fitting lenses is safer than another. To achieve this, a randomized clinical trial is needed.

Contact Lenses↗
PubMed2005

Corneal asphericity and apical curvature in children: a cross-sectional and longitudinal evaluation.

PURPOSE: The contour of the human cornea is closely modeled by a conic section, which is fully described by asphericity (Q) and apical radius of curvature (r(o)). The relationship between corneal shape and other ocular dimensions in children, including anterior and vitreous chamber depths, axial length, and spherical equivalent refractive error, was investigated. METHODS: Corneal asphericity and r(o) were calculated by using corneal topography data on 643 children (72 myopes, 370 emmetropes, and 201 hyperopes), ages 6 to 15 years, who participated in the Orinda Longitudinal Study of Myopia (OLSM) during 1991. Measurements from a younger subset of these children, including 8 myopes, 92 emmetropes, and 75 hyperopes, ages 6 to 9 years in 1991, were compared to 1996 data for longitudinal analysis. RESULTS: Mean +/- SD Q of the 1991 study sample was -0.346 +/- 0.101, representing a prolate corneal shape. Almost all (99.7%) of the corneas examined were prolate. Corneal asphericity was less prolate among myopes than in emmetropes and hyperopes (P = 0.010). Less prolate corneas were related to deeper anterior chamber depths among emmetropes (r = 0.324, P < 0.0001) and hyperopes (r = 0.275, P < 0.0001), but not among myopes (r = 0.230, P = 0.0515). Flatter values of r(o) were related to longer vitreous chamber depth (r = 0.607, P < 0.0001) and axial length (r = 0.606, P < 0.0001) in all refractive error groups. Initial corneal shape was unrelated to change in refractive error over a 5-year period. CONCLUSIONS: Most corneas examined in this study were prolate in contour. Deeper anterior chamber depths were related to less prolate corneas among emmetropes and hyperopes, which is probably the result of mechanical influences on the peripheral cornea as the anterior chamber elongates during ocular growth. Longitudinal results suggest initial corneal shape is of little or no value in predicting refractive error progression.

Adolescent↗
PubMed2005

Comparison of ocular component growth curves among refractive error groups in children.

PURPOSE: To compare ocular component growth curves among four refractive error groups in children. methods Cycloplegic refractive error was categorized into four groups: persistent emmetropia between -0.25 and +1.00 D (exclusive) in both the vertical and horizontal meridians on all study visits (n = 194); myopia of at least -0.75 D in both meridians on at least one visit (n = 247); persistent hyperopia of at least +1.00 D in both meridians on all visits (n = 43); and emmetropizing hyperopia of at least +1.00 D in both meridians on at least the first but not at all visits (n = 253). Subjects were seen for three visits or more between the ages of 6 and 14 years. Growth curves were modeled for the persistent emmetropes to describe the relation between age and the ocular components and were applied to the other three refractive error groups to determine significant differences. results At baseline, eyes of myopes and persistent emmetropes differed in vitreous chamber depth, anterior chamber depth, axial length, and corneal power and produced growth curves that showed differences in the same ocular components. Persistent hyperopes were significantly different from persistent emmetropes in most components at baseline, whereas growth curve shapes were not significantly different, with the exception of anterior chamber depth (slower growth in persistent hyperopes compared with emmetropes) and axial length (lesser annual growth per year in persistent hyperopes compared with emmetropes). The growth curve shape for corneal power was different between the emmetropizing hyperopes and persistent emmetropes (increasing corneal power compared with decreasing power in emmetropes). conclusions Comparisons of growth curves between persistent emmetropes and three other refractive error groups showed that there are many similarities in the growth patterns for both the emmetropizing and persistent hyperopes, whereas the differences in growth lie mainly between the emmetropes and myopes.

Adolescent↗
PubMed2005

Axial growth and changes in lenticular and corneal power during emmetropization in infants.

PURPOSE: To evaluate the contribution made by the ocular components to the emmetropization of spherical equivalent refractive error in human infants between 3 and 9 months of age. METHODS: Keratophakometry in two meridians was performed on 222 normal-birthweight infant subjects at 3 and 9 months of age. The spherical equivalent refractive error was measured by cycloplegic retinoscopy (cyclopentolate 1%). Anterior chamber depth, lens thickness, and vitreous chamber depth were measured by A-scan ultrasonography over the closed eyelid. RESULTS: Both the mean and SD for spherical equivalent refractive error decreased between 3 and 9 months of age (+2.16 +/- 1.30 D at 3 months; +1.36 +/- 1.06 D at 9 months; P < 0.0001, for the change in both mean and SD). Average ocular component change was characterized by increases in axial length, thinning, and flattening of the crystalline lens, increases in lens equivalent refractive index, and decreases in lens and corneal power. Initial refractive error was associated in a nonlinear manner with the change in refractive error (R(2) = 0.41; P < 0.0001) and with axial growth (R(2) = 0.082; P = 0.0005). Reduction in hyperopia correlated significantly with increases in axial length (R(2) = 0.16; P < 0.0001), but not with changes in corneal and lenticular power. Decreases in lenticular and corneal power were associated with axial elongation (R(2) = 0.40, R(2) = 0.12, respectively; both P < 0.0001). CONCLUSIONS: Modulation in the amount of axial growth in relation to initial refractive error appeared to be the most influential factor in emmetropization of spherical equivalent refractive error. The associations between initial refractive error, subsequent axial growth, and change in refractive error were consistent with a visual basis for emmetropization. The cornea and crystalline lens lost substantial amounts of dioptric power in this phase of growth, but neither appeared to play a significant role in emmetropization.

Accommodation, Ocular↗
PubMed2004

A randomized trial of the effects of rigid contact lenses on myopia progression.

OBJECTIVE: To compare the effects of rigid gas-permeable contact lenses (RGPs) and soft contact lenses (SCLs) on myopia progression in children. METHODS: We randomly assigned 116 subjects to wear RGPs or SCLs. Subjects underwent cycloplegic autorefraction, keratometry, and A-scan ultrasonographic axial length measurements at each annual visit. All analyses were conducted according to the original randomization assignment. The primary outcome measure was the 3-year change in spherical equivalent cycloplegic autorefraction. RESULTS: The mean +/- SD spherical equivalent cycloplegic refractive error progressed -1.56 +/- 0.95 diopters (D) for RGP wearers and -2.19 +/- 0.89 D for the SCL wearers during the 3 years of the study (analysis of covariance [ANCOVA], P<.001). The axial growth of the eyes was not significantly different between treatment groups (ANCOVA, P = .57). The steep corneal meridian of the RGP wearers steepened 0.62 +/- 0.60 D, and that of the SCL wearers steepened 0.88 +/- 0.57 D during the 3 years (ANCOVA, P = .01). CONCLUSIONS: The RGP wearers' myopia progressed less than that of the SCL wearers. The corneal curvature of the SCL wearers steepened more than that of the RGP wearers, but the axial growth was not significantly different between the groups. Most refractive error treatment effect was limited to the first year of the trial. The results of the study provide information for eye care practitioners to share with their patients, but they do not indicate that RGPs should be prescribed primarily for myopia control.

Child↗
PubMed2004

Quality of life in keratoconus.

PURPOSE: Keratoconus is a chronic, noninflammatory disease of the cornea with onset in early adulthood. As these years are important to financial and social health, keratoconus may have more severe impact on quality of life than would be expected given its clinical severity. We examined the vision-related quality of life of patients in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. DESIGN: Cross-sectional study. METHODS: The National Eye Institute-Visual Function Questionnaire (NEI-VFQ) was administered to 1166 CLEK Study patients at their first annual follow-up examination. Associations between clinical and demographic factors and NEI-VFQ scale scores were evaluated. RESULTS: Binocular entrance visual acuity worse than 20/40 was associated with lower quality of life scores on all scales except General Health and Ocular Pain. A steep keratometric reading (average of both eyes) >52 diopters (D) was associated with lower scores on the Mental Health, Role Difficulty, Driving, Dependency, and Ocular Pain scales. Scores for CLEK patients on all scales were between patients with category 3 and category 4 age-related macular degeneration (AMD) except General Health, which was better than AMD patients, and Ocular Pain, which was worse than AMD patients. CONCLUSIONS: Keratoconus is a disease of relatively low prevalence that rarely results in blindness, but because it affects young adults, the magnitude of its public health impact is disproportionate to its prevalence and clinical severity.

Adult↗
PubMed2004

Reasons patients recommend laser in situ keratomileusis.

PURPOSE: To evaluate the reasons patients who have had laser in situ keratomileusis (LASIK) recommend it to others and examine the disparity between high levels of satisfaction and patient reports of night-vision symptoms and/or dry eye after LASIK. SETTING: Northeastern Eye Institute, Scranton, and the University of Pittsburgh, Pittsburgh, Pennsylvania, and the University of California at Los Angeles, Los Angeles, California, USA. METHODS: Questionnaires assessing symptoms and satisfaction after LASIK were mailed to 2,100 patients. The questionnaires included items about night-vision symptoms and satisfaction and an open-ended question for patients to give their reasons for recommending LASIK to others. The open-ended responses were categorized and tabulated. RESULTS: Four hundred thirty-four patients provided reasons for recommending LASIK to others. Sixteen categories of reasons were identified. "No more spectacles/contact lenses" was listed by 180 patients (42%), followed by "better vision" (21%) and "convenience" (15%). Women were significantly more likely to cite "better comfort" (27 women versus 3 men; chi square = 8.99, P =.003) and "better quality of life" (41 women versus 9 men; chi square = 7.36, P =.007) as a reason for recommending LASIK. Of the 35 patients who reported dissatisfaction with post-LASIK vision, 20 (57%) would recommend LASIK to a friend because "LASIK helps others." CONCLUSIONS: Categories of reasons for recommending LASIK to others were similar to reasons given by patients for seeking LASIK. Some patients who reported dissatisfaction with their vision said they would recommend LASIK, suggesting that recommendation of LASIK to others is not necessarily a measurement of the quality of a patient's vision after LASIK.

Adult↗
PubMed2004

The repeatability of clinical measurements of dry eye.

PURPOSE: The repeatability of individual dry eye diagnostic tests has been reported in the literature on normal samples of patients and to a lesser degree in dry eye patients. In this study, the repeatability of a battery of clinical diagnostic tests for dry eye was assessed on mild to moderate dry eye patients. METHODS: A dry eye examination was performed on 75 patients on two occasions by a single examiner. The battery of dry eye tests included symptom assessment, contact lens and medical history, slit-lamp biomicroscopic evaluation of the eyelids, evaluation of Meibomian glands, assessment of tear film quality, tear meniscus height, assessment of blink quality, fluorescein tear breakup time (TBUT), fluorescein and rose bengal staining of the cornea and conjunctiva, phenol red thread test, and Schirmer test. RESULTS: The repeatability of subjective report of dryness (kappaW = 0.62) and grittiness (kappaW = 0.73) was moderate to high. In contrast, the repeatability of Meibomian gland disease classification (kappaW = 0.20), presence or absence of inferior corneal fluorescein staining (kappa = 0.25), and inferior conjunctival rose bengal staining (kappa = 0.21) was poor. When a summed staining score of corneal and conjunctival regions was evaluated, weighted kappa reliability was fair. The repeatability of tear breakup time was substantial [95% limits of agreement -5.71 to 5.83 seconds; intraclass coefficient coefficient (ICC) 0.65], and improved when the two timed readings were averaged. Repeatability of the Schirmer test is more variable as wetting scores increase. When the average Schirmer scores </= 10 mm were evaluated, moderate repeatability was demonstrated, indicating that the test performs better with more advanced disease. CONCLUSION: Although patient-reported symptoms are moderately repeatable from visit to visit, many of the procedures clinically used to diagnose and monitor dry eye syndromes are largely unrepeatable.

Adult↗