Abstract: Objective To evaluate the effects of rigid gas permeable contact lens (RGPCL) on aphakic infants with nystagmus and strabismus after congenital cataract surgery. Design Retrospective cohort study. Participants 120 cases (176 eyes) of aphakic infants with nystagmus and strabismus after congenital cataract surgery were enrolled. Methods The treatment modality was determined by parents.67 cases (108 eyes) were fitted with spectacles and 53 cases (68 eyes) were fitted with RGPCL. Best corrected visual acuity, eye position, strabismus degree, and nystagmus of the two groups were reviewed at baseline and every 6 months for up to 3 years. Main Outcome Measures Best corrected visual acuity (LogMAR), with nystagmus or not, strabismus degree. Results The LogMAR visual acuity of the spectacles group and RGPCL group was (1.345±0.339) and (1.406±0.361) at the baseline, and improved to (1.106±0.342) and (0.547±0.270) at 3 years respectively. Best corrected visual acuity in RGPCL group at 3 years was better than the spectacles group (z=5.155, P<0.001)．There were 67 cases with nystagmus in the spectacles group at the baseline, and 67 patients remained after 3 years. In RGPCL group, there were 53 cases at the first time and 42 cases after 3 years. There was significant difference in the number of cases with nystagmus between the two groups at 3 years (P<0.001). In addition, the strabismus degree at 33 cm was also examined. In the spectacles group, 60(89.6%) cases had strabismus with degree < 15°, 7(10.4%) cases had 15°~30°strabismus degree and no cases had strabismus ＞30°. After 3 years, the cases with different strabismus degree were reviewed 37(55.2%), 26(38.8%) and 4(6.0%) respectively.  In RGPCL group, 49(92.5%) cases had strabismus with degree <15° and 4(7.5%) cases had 15°~30° strabismus degree. After 3 years, the cases became to 51(96.2%) and 2(3.8%) respectively. No cases had strabismus ＞30° before and after RGPCL  treatment. There was significant difference in the improvement of strabismus degree between the two groups (P<0.001). Conclusions Best corrected visual acuity (LogMAR) of the patients with RGPCL treatment for 36 months was better than those with spectacles. After wearing RGPCL for 3 years, nystagmus disappeared in about 20% patients, and the ratio of strabismus with degree <15° increased. The mechanism needs to be further studied. (Ophthalmol CHN, 2023, 32: 154-159)

Key words:  infantile aphakia, rigid gas permeable contact lens, nystagmus, strabismus