Can I drive after those drops, doctor?

Phentolamine Eye Drops Reverse Pharmacologically Induced Mydriasis in a Randomized Phase 2b Trial

SIGNIFICANCE

After a dilated eye examination, many patients experience symptoms of prolonged light sensitivity, blurred vision, and cycloplegia associated with pharmacological mydriasis. Phentolamine mesylate ophthalmic solution (PMOS) may expedite the reversal of mydriasis in patients, potentially facilitating return to functional vision and reducing barriers to obtaining dilated eye examinations.

PURPOSE

The protracted reversal time after pharmacologically induced pupil dilation impairs vision. We tested the hypothesis that PMOS rapidly reduces pupil diameter in this acute indication.

METHODS

In this double-masked placebo-controlled, randomized, two-arm crossover phase 2b trial, we evaluated the effects of one drop of 1% PMOS applied bilaterally in subjects who had their pupils dilated by one of two common mydriatic agents: 2.5% phenylephrine or 1% tropicamide. End points included change in pupil diameter, percent of subjects returning to baseline pupil diameter, and accommodative function at multiple time points.

RESULTS

Thirty-one subjects completed the study (15 dilated with phenylephrine and 16 with tropicamide). Change in pupil diameter from baseline at 2 hours after maximal dilation with 1% PMOS was -1.69 mm and was significantly greater in magnitude compared with placebo for every time point beyond 30 minutes (P < .05). At 2 hours, a greater percentage of study eyes given 1% PMOS returned to baseline pupil diameter compared with placebo (29 vs. 13%, P = .03), which was this also seen at 4 hours (P < .001). More subjects treated with PMOS in the tropicamide subgroup had at least one eye returning to baseline accommodative amplitude at 2 hours (63 vs. 38%, P = .01). There were no severe adverse events, with only mild to moderate conjunctival hyperemia that resolved in most patients by 6 hours.

CONCLUSIONS

Phentolamine mesylate ophthalmic solution at 1% reversed medically induced pupil dilation more rapidly than placebo treatment regardless of which mydriatic was used (adrenergic agonists and cholinergic blockers) with a tolerable safety profile.

[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.

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.

Pupil dilatation does affect some aspects of daytime driving performance

AIMS

To examine the effects of pupil dilatation on driving performance and determine whether this was related to changes in standard measures of visual function.

METHODS

The driving and vision performance of 16 young, visually normal participants was measured with both normal and dilated pupils. Pupils were dilated with 1% tropicamide. Driving performance was measured under daytime conditions on a closed road circuit that was free of other vehicles and has been used in previous studies of driving performance. Measures included road sign detection and recognition, hazard detection and avoidance, gap perception and negotiation, driving reaction times and time to complete the circuit. Visual performance measures included high contrast visual acuity, Pelli-Robson letter contrast sensitivity, and glare sensitivity.

RESULTS

Pupil dilatation significantly (p<0.05) decreased the ability of participants to recognise low contrast hazards and avoid them, decreased their visual acuity and contrast sensitivity and increased glare sensitivity. The decreases in vision performance were not, however, significantly related to the decrement in driving performance.

CONCLUSION

Pupil dilatation can impair selected aspects of driving and vision performance and patients should be cautioned about these possible effects.

Driving ability after pupillary dilatation

BACKGROUND

The Royal College of Ophthalmologists' guidelines and Driver and Vehicle Licensing Agency (DVLA) recommend that a patient should not drive with dilated pupils based on the rationale that vision may be compromised in acuity and ability to tolerate glare. Arguments exist against these recommendations suggesting that pupillary dilatation does not have any real bearings on driving ability. Aim To determine the effects of pupillary dilatation on the ability to drive.

METHODS

The study was randomised and prospective. A total of 28 patients had their visual parameters (distance vision, near vision, licence plate reading at 20 m or shorter, and glare) measured and analysed pre- and post-tropicamide 1% dilatation. Paired two-tailed Student's t-test and chi(2)-test were used in the analysis.

RESULTS

At 20 min, following instillation of one drop of tropicamide 1% there is a significant reduction in visual acuity (VA), for distance Snellen and near. There is a significant reduction in the number of people who could read the licence plate at 20 m. Subjective glare assessment changed from 'none' (average score) in the undilated state to 'mild' in the dilated states. The overall patient feedback indicated that a significant 14% believed they would find it difficult to drive postdilatation.

CONCLUSION

This study demonstrates the rationale behind disallowing driving following pupillary dilatation. The risks to safe driving are proved significant as a result of significant reduction in visual quality and quantity after dilatation.

Mydriasis and glaucoma: exploding the myth. A systematic review

AIMS

To investigate the risk of inducing acute glaucoma following mydriasis.

METHODS

Systematic review of published research 1933-1999.

RESULTS

The risk of inducing acute glaucoma following mydriasis with tropicamide alone is close to zero, no case being identified. The risk with long-acting or combined agents is between 1 in 3,380 and 1 in 20,000. The presence of chronic glaucoma constitutes no additional risk.

CONCLUSIONS

Mydriasis with tropicamide alone is safe even in people with chronic glaucoma. It should be advised in all patients when thorough retinal examination is indicated.

The effect of pupil dilation with tropicamide on vision and driving simulator performance

PURPOSE

To assess the effect of pupil dilation on vision and driving ability.

METHODS

A series of tests on various parameters of visual function and driving simulator performance were performed on 12 healthy drivers, before and after pupil dilation using guttae tropicamide 1%. A driving simulator (Transport Research Laboratory) was used to measure reaction time (RT), speed maintenance and steering accuracy. Tests of basic visual function included high- and low-contrast visual acuity (HCVA and LCVA), Pelli-Robson contrast threshold (CT) and Goldmann perimetry (FIELDS). Useful Field of View (UFOV--a test of visual attention) was also undertaken. The mean differences in the pre- and post-dilatation measurements were tested for statistical significance at the 95% level using one-tail paired t-tests.

RESULTS

Pupillary dilation resulted in a statistically significant deterioration in CT and HCVA only. Five of 12 drivers also exhibited deterioration in LCVA, CT and RT. Little evidence emerged for deterioration in FIELDS and UFOV. Also, 7 of 12 drivers appeared to adjust their driving behaviour by reducing their speed on the driving simulator, leading to improved steering accuracy.

CONCLUSIONS

Pupillary dilation may lead to a decrease in vision and daylight driving performance in young people. A larger study, including a broader spectrum of subjects, is warranted before guidelines can be recommended.

Vision impairment and driving

Driving is the primary mode of travel in many countries. It facilitates the performance of routine daily activities and is thus integral with the concept of quality of life. Vision is inarguably a fundamental component of safe driving. Drivers with certain eye conditions reduce their driving exposure and restrict their driving to the safest times, yet there is preliminary evidence that some eye conditions increase the risk of crashes. Visual acuity is only weakly related to crash involvement, whereas peripheral vision appears to play a more critical role. Color vision deficiency by itself is not a threat to safe driving. Based on the current literature, it is unclear whether other types of visual sensory impairment have a significant impact on driving safety and performance. Tests of visual attention and processing speed show great promise as methods of identifying high-risk drivers. There is a serious need for well-designed studies in key practical areas, such as the safety of low-vision drivers who use bioptic telescopes, the impact of monocular vision impairment on safety, and the effectiveness of vision rescreening policies after initial licensure. For ophthalmologists to guide patients about driving fitness, valid and reliable assessment tools must be developed and made widely available.