Driving ability after pupillary dilatation

Comparison of experiences and preferences following non-invasive cardiovascular risk procedures: a cross-sectional survey in participants with and without diabetes mellitus

Aims

Endothelial dysfunction is an early risk marker of cardiovascular disease in diabetes mellitus. Timely screening is important in reducing cardiovascular disease-associated morbidity and mortality. This cross-sectional study investigates the acceptability and preferability of non-invasive cardiovascular risk procedures (EndoPAT2000 system and the ECG-gated fundoscope) in participants with diabetes mellitus compared to controls.

Methods

A self-administered Likert scale-based questionnaire was completed by 106 controls and 117 participants with diabetes mellitus, identified through stratified random sampling, upon conclusion of an Australian Heart Eye sub-study conducted at Westmead Hospital, NSW, Australia from 2012 to 2014. Pearson’s χ² test, independent-samples t-test and regression analysis were performed.

Results

Study participants who responded to the questionnaire had no preference for procedures (controls: 2.4 ± 1.1 vs diabetes mellitus: 2.5 ± 0.9, p = 0.38) but had an overall more negative experience with most aspects of the ECG-gated fundoscope than the EndoPAT2000 system. Of those with diabetes mellitus, participants who provided poorer self-rated health expressed discomfort with the mydriatic drops (ß 0.27, 95%CI 0.001 - 0.54, p = 0.049) and the fundoscope’s green light filter (ß 0.27, 95%CI 0.07 - 0.47, p = 0.009), as well as maintaining still (ß 0.40, 95%CI 0.08 - 0.72, p = 0.02) and not blinking (ß 0.38, 95%CI 0.07 - 0.70, p = 0.02) during photo acquisition. These participants were also less willing to repeat the ECG-gated fundoscope procedure (ß 0.29, 95%CI 0.07 - 0.52, p = 0.01).

Conclusions

Participants with diabetes mellitus, especially with poorer self-rated health, had a more negative experience with the ECG-gated fundoscope than the EndoPAT2000 system. Difficulties experienced under examination by the ECG-gated fundoscope appear related to the procedural design, which requires amendments improving patient comfort and compliance.

Prediction for Cycloplegic Refractive Error in Chinese School Students: Model Development and Validation

Purpose

To predict cycloplegic refractive error using measurements obtained under noncycloplegic conditions.

Method

Refractive error was measured in 5- to 18-year-old Chinese students using a NIDEK autorefractor before and after administration of 0.5% tropicamide. Spherical equivalent (SER) in diopters (D) was calculated as sphere plus half cylinder. A multivariable prediction model for cycloplegic SER was developed using data from students in Jinyun (n = 1938) and was validated using data from students in Hangzhou (n = 1498). The performance of the prediction model was evaluated using R², mean difference between predicted and measured cycloplegic SER, and sensitivity and specificity for predicting myopia (cycloplegic SER ≤ −0.5 D).

Results

Among 3436 students (mean age, 9.7 years; 51% female), the mean (SD) noncycloplegic and cycloplegic SER values were −1.12 (1.97) D and −0.20 (2.19) D, respectively. The prediction model that included demographics, noncycloplegic SER, axial length/corneal curvature radius ratio, uncorrected visual acuity (UCVA), and intraocular pressure predicted cycloplegic SER with R² of 0.93 in the development dataset and 0.92 in the validation dataset. The mean (SD) differences between predicted and measured cycloplegic SER were 0.0 (0.55) D in the development dataset and 0.06 (0.64) D in the validation dataset. In both the development and validation datasets, the combination of predicted SER and UCVA yielded high sensitivity (91.4% and 91.9%, respectively) and specificity (95.0% and 90.1%, respectively) for detecting myopia.

Conclusions

Cycloplegic refractive error can be predicted using measurements obtained under noncycloplegic conditions. The prediction model could potentially be used to correct the myopia prevalence in epidemiological studies in which administering cycloplegic agent on all participants is not feasible.

Translational Relevance

The prediction model may provide a tool for correcting the overestimation of myopia from noncycloplegic refractive error in future epidemiological studies in which administering cycloplegic agent on all participants is not feasible.

Effect of Cycloplegia on Refractive Error Measure in Chinese School Students

PURPOSE

To determine differences in cycloplegic vs. non-cycloplegic refractive error and factors associated with these differences in Chinese school students.

METHOD

In this cross-sectional school-based study, refractive error was measured in school students using a NIDEK autorefractor before and after administration of 0.5% tropicamide. Spherical equivalent (SER) in diopters (D) was calculated as sphere plus half cylinder. SER differences before vs. after cycloplegia were evaluated using mean, standard deviation (SD), 95% limits of agreement. Univariable and multivariable regression models were used to determine factors associated with SER differences.

RESULTS

Among 3604 students, 3450 (95.7%) provided data for analysis. Mean age (SD) was 9.7 (3.6) years. The mean SER (SD) was -1.12 (1.97) D before cycloplegia, and -0.20 (2.19) D after cycloplegia, with a mean difference of 0.92 D (95% limits of agreement: -0.93 to 2.78 D). Among 196 eyes with non-cycloplegic SER -6.0 D or worse (e.g., met high myopia definition), 71.4% had cycloplegic SER -6.0 D or worse, and among 3607 eyes with non-cycloplegic SER -0.5 D or worse (e.g., met myopia definition), 62.1% eyes had cycloplegic SER -0.5 D or worse. Cycloplegic SER was more correlated with axial length than non-cycloplegic SER (Pearson r = 0.82 vs. 0.72, p < .0001). In multivariable analysis, larger SER differences were associated with more hyperopic refractive error and smaller axial length (all p < .0001).

CONCLUSION

Non-cycloplegic refractive error overestimates myopia by approximately one diopter. This overestimation increases with more hyperopic refractive error and smaller axial length. Non-cycloplegic refractive error should not be used for evaluating pediatric myopia.

ABBREVIATIONS

BCVA = best corrected visual acuity; D = diopter; SD = standard deviation; SE = standard error; SER = spherical equivalent; CI = confidence interval.

Long-Term Effect on HbA1c in Poorly Controlled Diabetic Patients Following Nonmydriatic Retinal Image Review at the Time of Endocrinology Visit

Background: Patient education demonstrates variable benefits on diabetes control. Introduction: To examine the effect of discussing nonmydriatic retinal imaging findings during a single endocrinology visit on HbA1c levels after 6, 12, and 60 months. Materials and Methods: Patients with HbA1c >8.0% and diabetic retinopathy were previously recruited for a prospective study looking at the change in HbA1c at 3 months between those assigned to a session of nonmydriatic imaging with discussion of retinal findings and those assigned to routine endocrinology evaluation alone. The patients were subsequently evaluated at 6, 12, and 60 months after the initial intervention. Results: Fifty-three of the 57 originally recruited intervention subjects (93%) and 48 of 54 subjects in the original control group (89%) were evaluated at 6 and 12 months and 44 patients in each group (75% and 81%, respectively) at 60 months. At 6 months, the intervention group maintained larger decreases in median HbA1c compared to control (-1.1 vs. -0.3, respectively, p = 0.002) with a trend persisting at 12 months (-0.6 vs. -0.2, respectively, p = 0.07). After 60 months, there was no significant difference in the median change in HbA1c between treatment and control groups (0.3 vs. 0.1, respectively, p = 0.54). Discussion: The short-term improvement in HbA1c resulting from discussion of retinal findings persists throughout the first year in this diabetic cohort, but its magnitude declines with time and becomes statistically insignificant at some point between 6 and 12 months. Conclusions: In patients with poorly controlled diabetes, retinal imaging review may help improve glycemic control but may require repetition periodically for benefit beyond 6 months.

[Impact of mydriatic eyedrops on distance visual acuity in patients with exudative age-related macular degeneration]

PURPOSE

To demonstrate a decrease in distance visual acuity (VA) following instillation of mydriatic eyedrops in eyes with exudative age-related macular degeneration (AMD).

MATERIALS AND METHODS

A prospective assessment in clinical practice was conducted in our ophthalmology department at the University Hospital of Tours from 7/19/2018 to 8/29/2018. Distance (ETDRS) and near (Parinaud) VA were assessed before and after instilling one drop each of tropicamide 0.5% and phenylephrine 10% in the 40 included eyes with exudative AMD.

RESULTS

The mean difference in distance VA before and after pupillary dilation (PD) was 0.06 LogMAR (SD=0.14) (P<0.01), i.e. -3.05 letters read (SD=7.52) on the ETDRS chart (P=0.01). For near VA, the mean difference was 0.16 LogMAR (SD=0.16) (P<0.001), i.e. -1.58 paragraphs read (SD=1.63) on the Parinaud chart (P<0.001).

DISCUSSION

The absence of a clinically significant loss in post-dilation distance VA for exudative AMD could be explained by negligible glare coming from the ETDRS chart, milder photophobia, low pre-dilation VA's and a balance between higher order optical aberrations and diffraction. The opposite result for near VA could essentially be explained by greater glare induced by the light illuminating the Parinaud chart.

CONCLUSION

Our primary goal was not achieved. A study presuming the absence of a clinically significant decrease in post-dilation distance VA would be necessary to consider directly measuring post-dilation VA in eyes with exudative AMD in our daily practice.

Diabetic Retinopathy Screening Ratio Is Improved When Using a Digital, Nonmydriatic Fundus Camera Onsite in a Diabetes Outpatient Clinic

OBJECTIVE

To evaluate the effect of onsite screening with a nonmydriatic, digital fundus camera for diabetic retinopathy (DR) at a diabetes outpatient clinic.

RESEARCH DESIGN AND METHODS

This cross-sectional study included 502 patients, 112 with type 1 and 390 with type 2 diabetes. Patients attended screenings for microvascular complications, including diabetic nephropathy (DN), diabetic polyneuropathy (DP), and DR. Single-field retinal imaging with a digital, nonmydriatic fundus camera was used to assess DR. Prevalence and incidence of microvascular complications were analyzed and the ratio of newly diagnosed to preexisting complications for all entities was calculated in order to differentiate natural progress from missed DRs.

RESULTS

For both types of diabetes, prevalence of DR was 25.0% (n = 126) and incidence 6.4% (n = 32) (T1DM versus T2DM: prevalence: 35.7% versus 22.1%, incidence 5.4% versus 6.7%). 25.4% of all DRs were newly diagnosed. Furthermore, the ratio of newly diagnosed to preexisting DR was higher than those for DN (p = 0.12) and DP (p = 0.03) representing at least 13 patients with missed DR.

CONCLUSIONS

The results indicate that implementing nonmydriatic, digital fundus imaging in a diabetes outpatient clinic can contribute to improved early diagnosis of diabetic retinopathy.

Comparison between Early Treatment Diabetic Retinopathy Study 7-field retinal photos and non-mydriatic, mydriatic and mydriatic steered widefield scanning laser ophthalmoscopy for assessment of diabetic retinopathy

AIMS

To compare non-mydriatic, mydriatic and steered mydriatic widefield retinal images with mydriatic 7-field Early Treatment Diabetic Retinopathy Study (ETDRS)-standards in grading diabetic retinopathy (DR).

METHODS

We examined 95 patients (190 eyes) with type 1 diabetes. A non-mydriatic, a mydriatic and four steered mydriatic 200° widefield retinal images were captured (Optos 200Tx, Optos plc, Dunfermline, Scotland) and compared to mydriatic 7-field 45° ETDRS images (Topcon 3D OCT-2000, Topcon, Tokyo, Japan). Images were graded for DR according to ETDRS-protocol by a trained and certified grader masked to the results of the corresponding grading. For agreement kappa-statistics were used.

RESULTS

Exact level agreement with 7-field images was found in 76.3%, 76.1% and 70.7% for non-mydriatic, mydriatic and steered mydriatic widefield images, respectively. Corresponding values for one-level agreement were 99.0%, 98.9% and 99.5%, respectively. Non-mydriatic matched mydriatic widefield images almost fully with exact and one-level agreement of 96.8% and 100.0%, respectively. Mydriatic steered images resulted in higher grading in 24 eyes.

CONCLUSIONS

Widefield images matched 7-field images favorably. Widefield images can be captured without pupil-dilation and only one image is needed. However, because of overlapping eyelashes and distortion some lesion might be missed. Mydriatic steered images in selected cases may solve some of these problems.

Targeted mydriasis strategies for diabetic retinopathy screening clinics

PURPOSE

To examine factors necessitating pupil dilation to achieve gradable diabetic screening photographs using a digital non-mydriatic camera and to establish techniques to predict the need for dilation and to validate them.

METHODS

Prospective clinic-based cross-sectional study with follow-up validation study. The participants' involved consecutive patients attending the diabetic retinopathy screening clinic at a University Hospital. Best corrected visual acuity, age, sex, pupil size, mean spherical equivalent, cataract grade and the requirement for dilation to achieve gradable photographs in 90 patients were recorded. Data analysis using principal component analysis and multivariate analysis of variance derived a set of equations to predict the requirement for dilation. The predictive powers of these equations were validated in an independent group of 51 patients.

RESULTS

Smaller pupil size, denser nuclear colour, older age, poorer best-corrected visual acuity, cortical lens opacity and posterior subcapsular lens opacity were associated with the need for dilation (P<0.001 in all). Single variables used in isolation had a poorer predictive value than combining variables. Dilating patients with either a pupil size>3.75 mm or age>59 years correctly allocates 83 and 78% of patients, respectively to dilation or not. Combining pupil size with age produces a decision table that improves the predictive value to 84%. In the validation study this table had a predictive value of 80%.

CONCLUSION

We have produced and validated criteria based on a range of clinical variables for application in a clinical setting that allows for the development of targeted mydriasis.

Patients' attitudes towards mydriasis for diabetic eye disease screening

AIMS

The purpose of the questionnaire was to explore attitudes of patients towards mydriasis for diabetic retinopathy screening.

METHODS

Two groups of patients were invited to take part: group 1 comprised patients attending the diabetic clinic and had previous experience of mydriasis, group 2 patients attending the mobile screening unit for non-mydriatic digital retinal photograph and who were not previously used to receiving mydriatic eye drops. Basic demographic data was recorded and the volunteers invited to complete a questionnaire.

RESULTS

292 patients were recruited into group 1 (median age 63 years range 20-94) and 103 into group 2 (median age 68 years range 29-96). 42% of patients in group 2 indicated that they were unhappy with the use of dilating eye drops and 26% of this group reported that they may be discouraged from attending screening for diabetic retinopathy if drops were introduced. These figures were statistically lower in group 1 at 8% and 1-8% respectively (p < 0.001). Blurring of vision was identified as the most troublesome feature of the use of mydriasis for patients. A large proportion of patients drove themselves to their last screening appointment; 58% in group 2 and 39% in group 1. A third of all patients (33%) indicated that they worked outside the home.

CONCLUSIONS

Many patients attending diabetic eye screening return to driving and work immediately after the appointment. Introduction of the use of routine drops may discourage attendance. Education and experience may have an important role in improving acceptability of mydriatic eye drops. Retinal screeners need to have clear guidelines with which to advise patients.

Can we predict which patients are at risk of having an ungradeable digital image for screening for diabetic retinopathy?

PURPOSE

We aimed to determine the reasons for, and variables which predicted, ungradeable retinal photographs during screening patients for diabetic retinopathy.

MATERIALS AND METHODS

Age, duration of diabetes, visual acuity, and HbA1c were recorded. Following dark adaptation, a single 45 degrees nonmydriatic photograph was taken of each fundus. The pupils were then dilated and the photograph repeated. Using slit lamp biomicroscopy, lenticular changes (LOCS III), and fundus appearance were recorded.

RESULTS

In ungradeable photographs the fovea could not be visualised in 98% of cases of images from nonmydriatic photography, and in 88% if mydriasis was used. Poor definition in the nonmydriatic image was associated with a subsequent ungradeable mydriatic photograph (P=0.001), however, the positive predictive value was poor (34%). Age, posterior subcapsular cataract, and near vision predicted ungradeable status of nonmydriatic photographs (P<0.001, P=0.004, P=0.006, respectively; regression analysis). Nuclear colour and poor definition of the nonmydriatic photograph predicted ungradeable status of mydriatic photographs (P=0.006 & P=0.001, respectively).

CONCLUSION

Inability to visualise the fovea is the commonest cause of an ungradeable image from digital retinal photography. Age and posterior subcapsular cataract were best predictors of ungradeable status of nonmydriatic fundus photographs. Nuclear colour was the strongest predictor for ungradeable mydriatic photography.

Change in dynamic visual acuity (DVA) by pupil dilation

OBJECTIVE

This study was conducted to assess dynamic visual acuity (DVA) under pupil dilation.

BACKGROUND

Pupil dilation may negatively affect driving performance.

METHODS

Thirty healthy young adults (mean age 29.4 years) with pupil dilation participated in this study as the Mydrin P group. In addition to them, 15 healthy young adults (mean age 28.5 years) without pupil dilation were enrolled as the control group. DVA was measured binocularly with free-head viewing at 0, 30, 60, 120, and 360 min after mydriatic drop instillation in both eyes. Pupil size was measured at each time.

RESULTS

In the Mydrin P group, DVA significantly improved at 30, 60, and 120 min (ANOVA; p < .01) but returned to the predilation level at 360 min (ANOVA; p = .61). Pupil size changed from 4.1 to 7.8 mm (ANOVA; p < .01) at 30 min after the instillation, and this level was maintained up to 120 min but returned to normal within 360 min. In the control group, DVA did not significantly change at all measured times (ANOVA; p > .9). DVA was significantly (p < .05) correlated with the pupil size at all measured times.

CONCLUSION

The improvement in DVA was related to the enlargement of the pupil. This study suggests that the pupil size is one factor that may affect DVA.

APPLICATION

Potential applications of this study include useful information to assess the effect of pupil dilation on driving performance.