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G Lynn Mitchell

Publications and source records attributed to G Lynn Mitchell.

At least 55 records · Page 3Linked to original sources
PubMed2003

Reliability and validity of refractive error-specific quality-of-life instruments.

OBJECTIVE: To evaluate the reliability and validity of the National Eye Institute Refractive Error Quality of Life Instrument (NEI-RQL-42) and the Refractive Status and Vision Profile survey (RSVP). METHODS: Eighty-one participants with good visual acuity (better than 20/30 best-corrected acuity in each eye) completed the NEI-RQL-42 and RSVP on 2 occasions. Noncycloplegic, subjective refractions and high-contrast visual acuity assessments were also performed. Statistical analyses addressed internal consistency, test-retest reliability, and validity (ie, concurrent and construct validity) of the 2 instruments. OUTCOME MEASURES: The NEI-RQL-42, RSVP survey, subjective refraction, and visual acuity. RESULTS: The internal consistency for the overall NEI-RQL-42 was excellent (Cronbach alpha = 0.91); and for the overall RSVP, good (Cronbach alpha = 0.81). Likewise, the test-retest reliability for the overall NEI-RQL-42 was excellent (intraclass correlation coefficient [ICC], 0.91; 95% limits of agreement, -9.1 to 10.1); and for the RSVP, fair (ICC, 0.76; 95% limits of agreement, -12.1 to 12.5). The NEI-RQL-42 overall score showed good concurrent validity as it correlated significantly with subjective refraction, whereas the RSVP overall score did not. The NEI-RQL-42 and RSVP showed similar construct validity in terms of refractive error discrimination, but the NEI-RQL-42 showed better construct validity when discriminating by the type of refractive correction used by patients. Between-instrument convergent and divergent validity was good. CONCLUSIONS: The NEI-RQL-42 and RSVP generally have good reliability and validity in this sample of patients with refractive error. However, other factors such as content should be considered in choosing 1 of these instruments for studies of refractive error correction.

Adult↗
PubMed2003

Patient satisfaction and visual symptoms after laser in situ keratomileusis.

PURPOSE: To examine preoperative risk factors for decreased satisfaction and symptoms of glare, halos, and/or starbursts after laser in situ keratomileusis (LASIK). DESIGN: Retrospective, case-control study. PARTICIPANTS: Participants were 604 previously myopic patients who underwent LASIK at least six months prior to completing the questionnaire. METHODS: Questionnaires about satisfaction and night vision symptoms were mailed to 2100 patients from the Northeastern Eye Institute, UCLA, and the University of Pittsburgh. Preoperative and postoperative ocular variables were collected from the medical charts of the 841 subjects who returned the questionnaire. MAIN OUTCOME MEASURES: Responses to various satisfaction and night vision symptom questions were compared to demographic and preoperative ocular variables using multivariate logistic regression. RESULTS: The questionnaire return rate was 42.9%. The mean age for all subjects was 43.0 +/- 10.6 years, and 63% of the subjects were women. Overall, 97% of the subjects would recommend LASIK to a friend. Among subjects who would not recommend LASIK to a friend, a significantly larger percentage reported that they experienced glare, halos, or starbursts (13 of 16 (81.3%) vs. 206 of 388 (53.1%), chi(2) = 4.9, p = 0.03). Also, subjects with flatter preoperative minimum corneal curvature values were more likely to report that they would not recommend LASIK to a friend (OR = 0.71, 95% confidence interval (CI) = (0.52, 0.96), p = 0.03). The median score for satisfaction with vision was 100%, or the maximum value of 127 mm on the visual analog scale. Increasing age was significantly associated with dissatisfaction with vision after LASIK (OR = 1.68, 95% CI = (1.10, 2.56), P = 0.02). Halos were reported by 30%, glare by 27%, and starbursts by 25% of all subjects. Subjects who reported starbursts had a significantly flatter preoperative minimum corneal curvature (43.54 +/- 1.60 D versus 43.92 +/- 1.69 D, t = 2.15, p = 0.03). Also, subjects who had surgical enhancement were more likely to experience glare, halos, and/or starbursts (OR = 2.14, 95% CI = (1.33, 3.46), p = 0.002). CONCLUSIONS: Most subjects are satisfied with their vision after LASIK. Our study suggests, however, that certain factors are associated with decreased satisfaction and night vision symptoms after LASIK. Some of these factors include: increasing age, flatter preoperative minimum corneal curvature, and surgical enhancement.

Adult↗
PubMed2003

The relation between tear film tests in patients with dry eye disease.

PURPOSE: The purpose of this report was to investigate the relation between dry eye diagnostic tests. METHODS: Dry eye patients were enrolled to complete a clinical examination, including the following dry eye tests: a meibomian gland evaluation, tear meniscus height, fluorescein tear breakup time, fluorescein staining of the cornea, the Schirmer 1 test, the phenol red thread test, and rose bengal staining of the conjunctiva. Statistical analyses, including correlation coefficients, the Wilcoxon sign rank test, chi-square test, and logistic regression were used to address the relation between these clinical tests of dry eye. RESULTS: There was a strong relation between the Schirmer test and fluorescein staining in all four statistical analyses. Similarly, there was also a strong relation between the phenol red thread test and both fluorescein and rose bengal staining. Finally, the results of the Schirmer test were associated with the tear breakup time test in three of four analyses. CONCLUSIONS: The results indicate that tests of aqueous deficiency (volume or production) are associated with ocular surface desiccation. This important relation should be recognized when choosing dry eye tests as outcomes in clinical trials and epidemiological studies.

Coloring Agents↗
PubMed2003

Surveillance with duplex ultrasound in traumatic spinal cord injury on initial admission to rehabilitation.

OBJECTIVE: To determine the prevalence of deep vein thrombosis (DVT) by surveillance duplex ultrasound in the traumatic spinal cord injury (SCI) population on admission to rehabilitation. DESIGN: Retrospective sequential case series. SETTING: Midwest regional, university-based, Commission on Accreditation of Rehabilitation Facilities-accredited acute rehabilitation center. METHODS: Charts of all patients with traumatic SCI admitted and discharged from January 1, 1996 through December 31, 1998 were reviewed. Preadmission data were collected on demographics, severity of injury, and DVT prophylaxis information, along with rehabilitation duplex ultrasound results and incidence of thromboembolic events. RESULTS: Ninety-two participants met the inclusion criteria. There were 68 men and 24 women with a mean age on admission of 32.4 years. On admission, 45 participants (49%) were classified as tetraplegic and 47 (51%) were classified as paraplegic; 63 (69%) had motor-complete lesions and 29 (31%) had motor-incomplete lesions. Of all the participants, 8 (8.7%) were found to have DVT on admission to rehabilitation. There were no statistically significant differences among participants with regard to age, sex, level of injury, or completeness of injury, when comparing those participants with DVT on admission, those without DVT on admission, and those with thromboembolic events diagnosed later in their hospitalization. Of the 84 participants who had negative duplex ultrasounds on admission, 4 individuals (4.8%) were found to have DVT and 4 (4.8%) had pulmonary emboli subsequently. In these 84 participants, DVT prophylaxis with low-molecular-weight heparin was found to be more effective than was adjusted-dose heparin in preventing thromboembolic phenomenon. CONCLUSION: Incidence of DVT remains high despite prophylaxis in traumatic SCI patients. Two thirds of DVT diagnosed in rehabilitation was identified on admission and one third was diagnosed later. Duplex ultrasound is an effective and valuable tool that assists in the diagnosis of asymptomatic DVT in patients with traumatic SCI who are initiating in-patient rehabilitation.

Adolescent↗
PubMed2003

Nearpoint of convergence: test procedure, target selection, and normative data.

BACKGROUND: The purpose of this study was to help determine the most appropriate target to be used for the assessment of the nearpoint of convergence, normative data for the break and recovery in adults, and the diagnostic value of the red-glass modification and repetition of the nearpoint of convergence. METHODS: A total of 175 subjects with normal binocular vision and 38 subjects with convergence insufficiency were evaluated. The nearpoint of convergence was measured three ways, with an accommodative target, a penlight, and a penlight with red and green glasses. The nearpoint of convergence was also measured using a penlight for 10 repetitions. RESULTS: Results suggest a clinical cutoff value of 5 cm for the nearpoint of convergence break and 7 cm for the nearpoint of convergence recovery with either an accommodative target or a penlight with red and green glasses. CONCLUSION: This study establishes normative data for the nearpoint of convergence break and recovery in the adult population and supports the value of various test modifications when other testing is equivocal.

Accommodation, Ocular↗
PubMed2003

Ocular component data in schoolchildren as a function of age and gender.

PURPOSE: To describe the refractive error and ocular components of a large group of school-aged children as a function of age and gender. METHODS: In this report, we describe the refractive error and ocular components of 2583 school-aged children (49.3% girls, overall mean [+/-SD] age 10.0 +/- 2.3). Measurement methods included cycloplegic autorefraction, autokeratometry, videophakometry, and A-scan ultrasonography. For statistical comparisons across gender and age, a critical point of alpha = 0.005 was used to assess significance because of the large sample size and the large number of comparisons made. RESULTS: Of these 2583 children, 10.1% were myopic (-0.75 D or more myopia in both meridians), and 8.6% were hyperopic (+1.25 D or more hyperopia in both meridians). As would be expected, there was a significant effect of age on refractive error (spherical equivalent, p < 0.0001), toward less hyperopia/more myopia. There was no significant difference in the average refractive error between girls and boys (p = 0.0192). Girls had steeper corneas than boys (0.74 D steeper in the vertical meridian and 0.63 D steeper in the horizontal meridian, p < 0.0001). There were no significant differences in corneal power with age (p = 0.16). Both older age and male gender were significantly associated with deeper anterior chambers (p < 0.0001 for both). The crystalline lens showed significant thinning with age (p < 0.0001), however, there was no significant difference in the lens thickness between girls and boys (p = 0.66). Both Gullstrand lens power and calculated lens power showed significant effects of age and gender (p < 0.0001 for both). Girls, on average, had Gullstrand lens powers that were 0.28 D steeper and calculated lens powers that were 0.80 D more powerful than boys. Axial length also showed significant effects of age and gender (p < 0.0001 for both). Girls' eyes were, on average, 0.32 mm shorter than those of boys. CONCLUSIONS: These cross-sectional data show a general pattern of ocular growth, no change in corneal power, and crystalline lens thinning and flattening between the ages of 6 and 14 years. Girls tended to have steeper corneas, stronger crystalline lenses, and shorter eyes compared with boys.

Adolescent↗
PubMed2003

The reliability and validity of hand-held refractometry water content measures of hydrogel lenses.

PURPOSE: To investigate within- and between-examiner reliability and validity of hand-held refractometry water content measures of hydrogel lenses. METHODS: Nineteen lenses of various nominal water contents were examined by two examiners on two occasions separated by 1 hour. An Atago N2 hand-held refractometer was used for all water content measures. Lenses were presented in a random order to each examiner by a third party, and examiners were masked to any potential lens identifiers. Intraclass correlation coefficients (ICC), 95% limits of agreement, and Wilcoxon signed rank test were used to characterize the within- and between-examiner reliability and validity of lens water content measures. RESULTS: Within-examiner reliability was excellent (ICC, 0.97; 95% limits of agreement, -3.6% to +5.7%), and the inter-visit mean difference of 1.1 +/- 2.4% was not biased (p = 0.08). Between-examiner reliability was also excellent (ICC, 0.98; 95% limits of agreement, -4.1% to +3.9%). The mean difference between examiners was -0.1 +/- 2.1% (p = 0.83). The mean difference between the nominally reported water content and our water content measures was -2.1 +/- 1.7% (p < 0.001); the 95% limits of agreement for this difference were -5.4% to +1.1%. CONCLUSION: There is good reliability within and between examiners in measuring water content of hydrogel lenses. However, with our sample of lenses, examiners tended to overestimate the nominal water content of hydrogel lenses. As discussed, this bias may be associated with the Brix scale used in refractometry and is material dependent. Therefore, investigators may need to account for bias when measuring hydrogel lens water content via hand-held refractometry.

Contact Lenses, Hydrophilic↗
PubMed2003

Validity and reliability of the revised convergence insufficiency symptom survey in children aged 9 to 18 years.

PURPOSE: To assess the validity and reliability of the Convergence Insufficiency Symptom Survey (CISS) in children aged 9 to 18 years. The CISS is the primary outcome measure for a pilot study evaluating two different treatments for convergence insufficiency (CI). METHODS: Children with CI were given the CISS twice to assess reliability. CISS scores for the first administration were also compared with scores from children with normal binocular vision to assess the validity of the CISS. RESULTS: Forty-seven children with CI and 56 children with normal binocular vision participated in the study. Reliability was assessed using intraclass correlation and 95% limits of agreement for the children with CI. For children with CI, the intraclass correlation was 0.77 (95% confidence interval, 0.613 to 0.873), and the 95% limits of agreement were -10.2 to +12.1. The mean (+/-SD) CISS score was 30.8 +/- 8.4 for the children with CI and 8.4 +/- 6.4 for the children with normal binocular vision. These means were significantly different (p < 0.0001). Good discrimination (sensitivity, 96%; specificity, 88%) was obtained using a score of >/=16. CONCLUSIONS: Children with CI showed a significantly higher CISS symptom score than children with normal binocular vision. The results of the study indicate that the CISS is a valid and reliable instrument to use as an outcome measure for children aged 9 to 18 who are enrolled in clinical research concerning CI.

Adolescent↗
PubMed2003

Corneal thickness results in the Menicon Z 30-day continuous wear and ACUVUE 7-day extended-wear contact lens clinical trial.

PURPOSE: This study was conducted to measure the corneal thickness changes associated with wearing 30-day tisilfocon A (Dk = 163) and 6-day etafilcon A (Dk = 28) contact lenses. The probable cause of the outcomes is discussed. METHODS: Thirty subjects were fitted with Menicon Z rigid gas-permeable (RGP) contact lenses and a control group (n = 30) was fitted with ACUVUE hydrogel lenses, at two study sites. After a 2-week period of daily wear, subjects began prolonged wear. Measurements were performed at the dispensing visit, and then at the 2-week daily wear, the 1-week, 6-month, and 12-month extended- and continuous-wear visits. RESULTS: Repeated measures analysis of covariance was performed on mean corneal thickness. There was a significant increase in corneal thickness in the hydrogel lens extended-wear group compared to the RGP group (P = 0.03). The mean corneal thickness in the ACUVUE group was 2.58% higher at the 2-week daily wear visit, 2.38% higher at the 1-week extended-wear visit, 2.96% higher at the 6-month, and 2.97% higher at the 1-year visit compared to the RGP continuous-wear patients. DISCUSSION: Patients wearing high-Dk RGP contact lenses for continuous wear may have thinner corneas (within the normal thickness range) probably because of minimal hypoxia-induced corneal stromal swelling; RGP-induced reversible corneal epithelial compression; deceased epithelial sloughing; or long-term contact lens-induced keratocyte apoptosis. Patients wearing hydrogel contact lenses for extended wear may have thicker corneas because of hypoxia-induced corneal stromal swelling. Additional evidence of corneal hypoxic stress is seen in the higher prevalence of striae and epithelial microcysts in the hydrogel group and greater variability of corneal thickness measurements in the soft contact lens group in our results.

Adult↗
PubMed2003

Corneal endothelial morphology results in the Menicon Z 30-day continuous-wear contact lens clinical trial.

PURPOSE: This evaluation was conducted as part of a protocol entitled Evaluation of the Menicon Z Rigid Gas Permeable Contact Lens for up to 30 Days Extended Wear. The purpose of the protocol was to compare corneal endothelial morphology changes after wearing rigid gas-permeable (RGP) Menicon Z contact lenses, continuously for up to 30 days, with ACUVUE (Johnson & Johnson Vision Care) hydrogel contact lenses, worn for up to 6 nights of extended wear. METHODS: Sixty patients, who were adapted to RGP daily wear and soft contact lens daily wear, were recruited at two study sites. The thirty subjects who wore RGP daily wear lenses were fitted with the Menicon Z (tisilfocon A, oxygen permeablility [Dk] = 163) RGP contact lens comprised the test group. The control group subjects (n = 30 former users of daily wear soft contact lenses) were fitted with ACUVUE (etafilcon A, Dk = 28) hydrogel contact lenses. After a 2-week adaptation period of daily wear, subjects began extended wear. Endothelial imaging was performed at the two study sites in this multicenter study (University Hospitals of Cleveland/Case Western Reserve University Department of Ophthalmology [CWRU] and The Ohio State University [OSU]). The hydrogel lens group was instructed to wear their lenses for 7 days and 6 nights before discarding the lenses and to sleep with no lenses on the seventh night. The RGP group was permitted to wear the lenses for up to 30 days and 29 consecutive nights before removing the lenses for cleaning and overnight soaking. RESULTS: CWRU had 24 patients (12 soft contact lens and 12 rigid contact lens) and OSU had 21 patients (12 soft contact lens and 9 rigid contact lens) who completed the study and were included in the analyses. Patients who were withdrawn from the study at CWRU included one RGP patient dropped out because of pregnancy; one RGP patient developed vascularized limbal keratitis and discomfort; one could not be fitted with a bitoric RGP; two soft lens patients moved from the area, and one dropped out because of dry eyes. At OSU, four patients dropped out due to discomfort (two in each lens type);one moved from the study area; one decided not to participate soon after the consent visit; one had worries of reduced vision at 6 months; one subject's attitude changed prior to the 6 month visit; and one subject was withdrawn for reasons of poor study schedule compliance. CONCLUSION: The Menicon Z lens wearers in this study did not show significant endothelial cell morphology changes after 1 year of nearly continuous contact lens wear. This finding is particularly important considering the RGP wearers in this study were older by a average of 10 years (mean age approximately 40) and had worn their contact lenses an average of almost 10 years longer than the soft contact lens wearers.

Adult↗
PubMed2003

Tear exchange and oxygen reservoir effects in silicone hydrogel systems.

PURPOSE: The effects of oxygen reservoir and tear exchange are known for conventional hydrogel contact lenses. This study attempted to (1) confirm their presence in lenses of a silicone hydrogel (SH) material and (2) evaluate their individual and combined contributions to hypoxic relief of the cornea. METHODS: Corneal oxygen uptake rates were measured polarographically for 10 OD corneas immediately after 300-sec periods (equivalent to 60+ blink cycles) of: (1) nonblink wear of a 0 Dk/L polymethylmethacrylate (PMMA) cap lens; (2) nonblink wear of that cap lens with a SH lens inserted between it and the cornea; (3) regular blinked wear of that same lens combination; (4) nonblinked wear of the SH lens alone; and (5) normal open-eye, non-lens wear. The rates for each eye had a ratio with its own baseline (no lens) rate, and the total sample mean was calculated for each condition from those individual eye means. RESULTS: (1) Under nonblink conditions, a 28% reduction in corneal oxygen demand was observed when a SH lens was inserted under the PMMA cap lens versus without. (2) When regular blinking was added to that lens combination, corneal oxygen demand decreased another 8%, for a total of 36%. The combination of SH insertion and blinking did achieve a statistically significant difference (P<0.05 by the Dunnett test) from the nonblink, 0 Dk/L, maximum deprivation condition. CONCLUSION: The statistically significant hypoxia reduction observed with the SH lens insertion and blinking indicates the additive presence of two factors: (1) a lens reservoir effect caused by the SH lens and (2) a bulk-flow tear exchange effect caused by blinking. Their respective contributions to the reduction of corneal oxygen demand over the period studied were found to be in the ratio of 3.4:1.

Adult↗
PubMed2002

Levels of agreement between parents' and children's reports of near work.

PURPOSE: To assess whether parents and children report the same information regarding children's near vision activities when given similar questionnaires. METHODS: Data from questionnaires administered to 406 children and their parents were analyzed to evaluate the agreement between parent and child reports. The questionnaires were completed during the 1994 testing of the Orinda Longitudinal Study of Myopia. Each child and parent was asked to categorize how often the child reads for pleasure. In addition, each subject was asked to estimate how many hours per week were spent in each of five visual activities. The weighted kappa statistic, paired t-tests, and polytomous logistic regression were used for analyses. RESULTS: A weighted kappa = 0.42 (moderate agreement) was found in the comparison of child-reported vs. parent-reported classification of reading. Agreement between parent- and child-reported number of hours spent doing homework (0.21), reading for pleasure (0.31), watching television (0.31), playing video games (0.31), and engaging in sports/outdoor activities (0.26) was fair for each activity. CONCLUSIONS: Although the results indicate fair to moderate levels of agreement, better methods of reporting near-work activities are needed for future myopia research.

Adolescent↗
PubMed2002

The performance of the contact lens dry eye questionnaire as a screening survey for contact lens-related dry eye.

PURPOSE: The contact lens dry eye questionnaire (CLDEQ) is a self-administered survey developed to examine the distribution of dry eye symptoms among contact lens wearers. In this report, we examine the CLDEQ as a screening survey for contact lens-related dry eye and compare it with McMonnies' questionnaire. METHODS: The CLDEQ and McMonnies' questionnaire were administered to 367 unselected contact lens wearers at six clinics across the United States and Canada. After completion of the surveys, doctors unaware of the survey results completed a separate form indicating contact lens-related dry eye diagnosis at the end of a nondirected clinical examination. The CLDEQ is composed of nine habitual symptom subscales and a self-diagnosis question, which were tested for their predictive value for a diagnosis of contact lens-related dry eye. McMonnies' instrument was scored with use of the algorithm suggested in the literature. Sensitivity, specificity, and receiver operator characteristic (ROC) curve analyses were performed for each instrument on the basis of logistic regression results. RESULTS: The area under the ROC curve for the CLDEQ was 0.74, indicating moderate contact lens-related dry eye discrimination, and the Hosmer-Lemeshow goodness-of-fit test indicated that the CLDEQ was well calibrated (p = 0.84). The area under the ROC curve for McMonnies' questionnaire was 0.56, indicating poorer discrimination, and the Hosmer-Lemeshow goodness-of-fit test indicated it was also poorly calibrated (p = 0.08) for contact lens wearers. CONCLUSIONS: These analyses suggest that the CLDEQ is capable of discriminating contact lens-related dry eye and is accurate in doing so, especially in comparison with McMonnies' questionnaire. The CLDEQ is an efficient screening survey and may be used in future clinical research and epidemiologic studies of contact lens-related dry eye.

Adolescent↗
PubMed2002

Performance and repeatability of the NEI-VFQ-25 in patients with dry eye.

PURPOSE: The use of the National Eye Institute Visual Function Questionnaire (NEI-VFQ) has increased as a method of assessing patients' impressions of their vision-specific quality of life. The purpose of this study was to assess the performance and test-retest repeatability of the 25-question format of the NEI-VFQ in patients with dry eye. METHODS: The self-administered NEI-VFQ-25 was administered to 75 patients with dry eye on two occasions in a university-based optometry practice. Dry eye severity was assessed with use of the European criteria for dry eye. The weighted kappa statistic (kappa(w)) was used to evaluate test-retest repeatability of the NEI-VFQ-25 individual test questions, and the 95% limits of agreement and the intraclass correlation coefficients were calculated for the overall VFQ and subscale scores. RESULTS: With use of the European dry eye criteria, 21.9% of participants were classified with moderate to severe dry eye. For the sample, the ocular pain subscale score was lower (indicating more ocular pain) than published normative values. Repeatability of individual NEI-VFQ-25 questions ranged from moderate to substantial (kappa(w) values: 0.42 [pain and discomfort] to 0.90 [stay home because of vision]). The intervisit mean (+/- standard deviation) difference in the overall VFQ score was -0.66 +/- 4.26 (95% limits of agreement: -9.02, 7.69), and the intraclass correlation coefficient for the ocular pain subscale was 0.57. CONCLUSION: Patients with dry eye have lower ocular pain subscale scores. The repeatability of the overall NEI-VFQ score and the subscale scores was moderate to high, and it may be influenced by the number of questions in each subscale.

Adult↗
PubMed2002

Use of the dry eye questionnaire to measure symptoms of ocular irritation in patients with aqueous tear deficient dry eye.

PURPOSE: To demonstrate the ability of the Dry Eye Questionnaire (DEQ) to characterize the frequency of ocular surface symptoms and their diurnal intensity in patients with Sjögren's syndrome (SS), keratoconjunctivitis sicca (KCS), and age-matched controls. METHODS: One hundred patients with tear-deficient dry eye from Toronto Western Hospital were mailed the DEQ and the McMonnies' questionnaire (MQ). Age- and gender-matched controls were selected from an historical data set. The DEQ measured the habitual frequency, intensity, and impact of common ocular surface symptoms and asked questions about computer use, medications, and allergies. RESULTS: Sixty-two dry eye subjects responded; 30 with SS and 32 with KCS. Compared with controls, SS subjects consistently reported the highest frequency and intensity of symptoms, followed by non-KCS subjects. The intensity of symptoms was significantly greater in the evening than in the morning among SS subjects for all symptoms except dryness and light sensitivity (p < 0.05). Sixty percent of SS subjects reported the need to stop daily activities and close their eyes due to dryness, burning, and light sensitivity. CONCLUSIONS: Symptoms of ocular irritation were frequent and intense among SS and KCS subjects. These symptoms often increased in intensity over the day, suggesting that open-eye conditions affect the progression of symptoms. Measurement of symptom frequency and diurnal intensity by the DEQ provides a sensitive tool that may be useful in clinical treatment trials for dry eye.

Activities of Daily Living↗
PubMed2002

Corneal staining in hydrogel lens wearers.

PURPOSE: The purpose of this study was to determine the factors that contribute to corneal staining in hydrogel lens wearers by examining the following variables: type of lens worn, wearing time and lens replacement schedule, lens care system, and topical and systemic medication use. METHODS: Five hundred full-time, successful hydrogel contact lens wearers were evaluated for corneal fluorescein staining at 20 clinical sites. Corneal staining was evaluated in five regions and was graded on a scale of 0 (no staining) to 4 (severe staining) in 0.5 steps for severity. RESULTS: Corneal fluorescein staining was present in at least one eye in 55.7% of the hydrogel lens wearers examined in this study, and 8.0% had moderate-to-severe staining (defined as a cumulative staining score of > or = 3 with at least one quadrant score > or = 2). Staining was most severe for the inferior portion of the cornea (mean +/- SD; OD: 0.34 +/- 0.57, OS: 0.30 +/- 0.54). All other areas of the cornea showed lesser amounts of staining, all of which were approximately equal (mean range, 0.13 to 0.16). Staining was observed in two or more quadrants in 24% of right eyes and 22.4% of left eyes. When questioned about care system compliance, 81.1% of subjects reported compliance. Patients who were noncompliant with their lens care system (chi 2 p = 0.0037), used rewetting drops (chi 2 p = 0.0005), or wore conventional lenses without a planned replacement schedule (chi 2 p = 0.0008) were more likely to have some degree of corneal staining. Noncompliance with care system (chi 2 p = 0.0147), replacement schedule (chi 2 p = 0.0039), and lens power (chi 2 p = 0.0224) were associated with moderate-to-severe staining. The following factors were not significantly associated with corneal staining: patient age, gender, medication use including oral contraceptives, type of wear (extended, flexible, or daily), average wearing time, wearing time at the examination, lens type (spherical or toric), water content of lenses (high or low water content), type of care system, use of enzymes, and pinching the contact lens directly off the cornea. CONCLUSIONS: Staining occurs to some extent in many hydrogel contact lens patients, and is influenced by many factors. Moderate-to-severe staining, which may be more clinically significant, is associated with noncompliance with care system, a conventional replacement schedule, and lens power.

Adult↗
PubMed2002

A survey of treatment modalities for convergence insufficiency.

BACKGROUND: Convergence insufficiency (CI) is a common and distinct binocular vision disorder. However, there is a lack of consensus regarding the treatment most appropriate for Cl. Possible treatment modalities include base-in prism, pencil pushup therapy (PPT), reading glasses, home-based vision therapy/orthoptics (HBVT), and office-based vision therapy/orthoptics (OBVT). The purpose of this study was to investigate the care process for Cl by surveying eyecare professionals regarding the most common treatment modalities used by both optometrists and ophthalmologists across the United States. METHODS: Surveys requesting doctors to indicate which treatment(s) they prescribed and believed to be most effective for symptomatic CI patients were mailed to 863 optometrists and 863 ophthalmologists in the United States. RESULTS: Fifty-eight percent of the optometrists responded to the survey; the most common treatment prescribed was PPT (36%) followed by HBVT (22%) and OBVT (16%). For the ophthalmologists (who had a 23% response rate), the most common treatment prescribed was PPT (50%) followed by HBVT (21 %) and base-in prism (10%). CONCLUSIONS: This survey suggests that most eyecare practitioners prescribe PPT as the initial treatment for CI.

Data Collection↗