Abstract
Purpose :
To compare the binocular vision status of patients 50 years of age and above pre- and post-cataract surgery, and to investigate the risk factors for patients who develop binocular vision anomalies after cataract surgery.
Methods :
In this prospective study, we enrolled patients (50 years or older) who were scheduled for bilateral cataract surgery from January to November 2019. A comprehensive binocular vision test battery was administered including measurement of eye alignment using the cover test, assessment of positive and negative fusional vergence (step vergence testing), vergence facility testing using 3BI/12BO prism, and the near point of convergence before the first surgery and the third visit after the second surgery. A detailed diagnostic classification protocol was applied to identify the presence of binocular vision anomalies pre- and post-surgery.
Results :
Seventy-three participants were included at baseline and 51 completed the postoperative evaluation. The mean age at baseline was 70.2±6.7 years and the mean follow-up time was 57.3±29.8 days after the second surgery. At baseline, 46 of 73 (63%) patients were diagnosed with non-strabismic binocular vision anomalies (NSBVA), including 40 (54.8%) with convergence insufficiency, 3 (4.1%) with basic exophoria , 2 (2.7%) with convergence excess, and 1 (1.4%) with fusional vergence dysfunction. One participant with convergence insufficiency also had a vertical phoria. Of the 51 participants who completed the postoperative evaluation, 60.8% had binocular vision disorders. There were a number of conversions from NSBVA to normal binocular vision and vice-versa (Table 1). Logistic regression showed that the adjusted odds ratio of preexisting NSBVA diagnosis for predicting risk of postoperative NSBVA was 8.8 (P<0.01).
Conclusions :
Binocular vision problems, especially convergence insufficiency, are prevalent in the elderly population with cataract. Cataract surgery does not seem to be a significant risk factor for the development of new binocular vision problems. The main risk factor for predicting a postoperative binocular vision problem is preexisting NSBVA. A limitation of the study is a lack of normative binocular vision data for the elderly population. This study suggests that normative data should be developed for patients 50 years of age and above.
This is a 2020 ARVO Annual Meeting abstract.