Potential acuity pinhole: A simple method to measure potential visual acuity in patients with cataracts, comparison to potential acuity meter☆
Presented in part at the American Academy of Ophthalmology annual meeting, New Orleans, Louisiana, November 1998.
Received 24 September 1998; accepted 22 March 1999.
Abstract
Objective
To describe the potential acuity pinhole (PAP) test and compare its accuracy to the potential acuity meter (PAM) in predicting visual outcome after cataract surgery.
Study design
Prospective case series.
Participants
A total of 56 preoperative patients with cataracts participated.
Main outcome measures
Accuracy of predicting postoperative distance visual acuity was measured.
Methods
Lines of inaccuracy were calculated by subtracting actual postoperative best-corrected distance visual acuity (BCVA) from predicted values. Variables analyzed were method of prediction, preoperative BCVA, and preoperative 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. The 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 inaccuracy for PAM predictions were 2.50, 2.68, and 6.22 lines for the same groups. 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, and III, respectively. There was no statistically significant correlation between 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 preoperative BCVA worse than 20/200. It appears to be more predictive than PAM.
Manuscript no. 98584.
1Center for Sight, Georgetown University Medical Center, Washington, DC, USA
2Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, USA
Address correspondence to Samir A. Melki, MD, PhD, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Harvard Medical School, 243 Charles Street, Boston, MA 02114, USA
☆ The authors have no proprietary interests in any material mentioned in this article.
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