Pharmocological Intervention to Improve Distance and Near Vision in Uncomplicated Pseudophakia
To determine if a) uncorrected distance (UDVA) and near acuity (UNVA) and, b) clinical depth of field (DoF) can be improved by topical administration of drops inducing changes in pupil size in pseudophakic eyes with low distance prescriptions.
UDVA was measured using a standard LogMAR, UNVA was measured using near chart at 40cm. DoF, at distance was measured by asking the patient to look at smallest letter with the best correction. Plus (a) lenses were racked up on the refractor head until quality of vision was unacceptable. This was repeated using minus lenses (b). Irrespective of lens sign, DoF = a+b. Mesopic pupil size was measured by infra-red pupillometry. Two drops of a custom made topical medication were instilled and measurements were repeated 30-45 minutes later. Subjects were complication free pseudophakes (33 eyes). Acuity converted to decimal notation.
Reporting just the significant association (p=<0.001) encountered in the 33 cases (eyes). The mean (±sd) before (i) and after (ii) findings were 1) Depth of Field (i) 1.48D(0.52), (ii) 2.69D (0.52). 2) Pupil size (i) 3.04mm(0.43), (ii) 1.98mm (0.29). 3) UDVA (i) 0.67 (0.18), (ii) 0.90 (0.15). 4) UNVA (i) 0.30 (0.17), (ii) 0.74 (0.14).
Near and distance UDVA improved after drop instillation, equivalent to one line of improvement. UNVA improved and the results show that intervention improved near vision from J6 to J3. One mm reduction in pupil size was associated with an increase in depth of field of 1.0D in the pseudophakic eyes.