Abstract
Purpose: :
To evaluate the standard visual acuity and visual acuity with different contrast targets in patients with retinitis pigmentosa (RP) after cataract surgery.
Methods: :
Nine eyes of eight patients with RP (3 men and 5 women) who underwent cataract surgery and implantation of a yellow intraocular lens were examined prospectively. The average age was 59.8±13.9 years. The best-corrected visual acuity (BCVA) in logMAR units, and the visual acuities under photopic and mesopic conditions with 100% and 10% contrasts were measured (CAT-CP, NEITZ) before and after cataract surgery.
Results: :
Under photopic conditions, the mean BCVA improved from 0.57 to 0.31 logMAR units (P=0.002), from 0.73 to 0.47 logMAR units with100% contrast (P=0.029), and from 1.1 to 0.8 logMAR units with10% contrast (P=0.006). Under mesopic conditions, the BCVA improved from 0.87 to 0.59 logMAR units with 100% contrast (P=0.02), but no significant improvement was found with 10% contrast (P=0.18). The mean improvement of the BCVA (0.26 logMAR units), both the 100% contrast BCVA under photopic (0.26 logMAR units) and mesopic conditions (0.28) vision and 10% contrast BCVA under photopic (0.3) were not significantly different. The improvement of the BCVA with the 10% contrast under mesopic conditions was significantly weaker (0.12) than that of others.
Conclusions: :
The BCVA,100% and 10% contrast visual acuity under photopic conditions and 100% contrast visual acuity under mesopic vision were significantly improved in patients with RP after cataract surgery with approximately the same degree of improvement . The lack of a significant improvement with 10% contrast under mesopic conditions was probably because of the disruption of the rod photoreceptors in RP patients.
Keywords: retinal degenerations: hereditary • cataract • contrast sensitivity