Potential acuity pinhole - A simple method to measure potential visual acuity in patients with cataracts, comparison to potential acuity meter

Objective: To describe the potential acuity pinhole (PAP) test and compare its accuracy to the potential acuity meter (PAM) in predicting visual outco me after cataract surgery, Study Design: Prospective case series. Participants: A total of 56 preoperative patients with cataracts participat ed. Main Outcome Measures: Accuracy of predicting postoperative distance visual acuity was measured. Methods: Lines of inaccuracy were calculated by subtracting actual postoper ative best-corrected distance visual acuity (BCVA) from predicted values. V ariables analyzed were method of prediction, preoperative BCVA, and preoper ative spherical equivalent, Results: The PAP test predicted visual outcomes within 2 lines in 100%, 100 %, and 56% of eyes with preoperative BCVA of 20/50 and better (group I), 20 /60 to 20/100 (group II), and 20/200 and worse (group III), respectively, T he PAM predictions within 2 lines for the same groups were 42%, 47%, and 0% , respectively. Mean lines of inaccuracy of PAP predictions were 0.83, 1,11 , and 3.50 lines for groups I, II, and III, respectively. Mean lines of ina ccuracy for PAM predictions were 2.50, 2.68, and 6.22 lines for the same gr oups. Differences in lines of prediction between PAM and PAP were 1.67 (P = 0.004), 1.58 (P = 0.0002), and 2.72 lines (P = 0.0001) for groups I, II, a nd III, respectively, There was no statistically significant correlation be tween PAP predictions and preoperative myopic spherical equivalent. Conclusions: The PAP test is a simple, inexpensive, and relatively reliable method to estimate visual outcome after uncomplicated cataract surgery in eyes with no coexisting disease. It is less accurate in patients with preop erative BCVA worse than 20/200. It appears to be more predictive than PAM.