The Comparison of Soft HydroCone (Toris K) Silicone Hydrogel and Rigid Gas-Permeable Contact Lenses in Patients With Posterior Microphthalmos.

Objective: To evaluate and compare soft HydroCone (Toris K) silicone hydrogel and rigid gas-permeable contact lenses (RGPCLs) in patients with posterior microphthalmos (PMs), for visual rehabilitation and comfort.

Methods: The records of 11 patients who were followed up in our hospital with the diagnosis of PM and were fitted with both Toris K and RGPCLs in our contact lens department were reviewed retrospectively. Patient age, gender, axial length (AL), topographic keratometry (K) values and best-corrected visual acuity (BCVA) with both lens types and subjective lens comfort status were recorded.

Results: A total of 22 eyes of 11 patients with a mean age of 20.9±11.1 years were included in the study. The mean AL were 16.01±0.1 and 15.9±0.2 mm in the right and left eyes, respectively. Mean K1 and K2 were 48.6±2.2 and 49.4±2.2 D, respectively. Mean logMAR BCVA of the 22 eyes before contact lens fitting was 0.63±0.56 with spectacle. After Toris K and RGPCLs fitting, mean logMAR BCVA were 0.43±0.20 and 0.35±0.25, respectively. Both lenses provided better visual acuity than spectacles; RGPCLs also provided significantly better visual acuity than HydroCone lens ( P <0.05). Eight of 11 patients (73%) had ocular discomfort with RGPLs, and there was no complaint with Toris K.

Conclusions: The corneal surfaces are steeper in patients with PMs than in normal population. For that reason, their vision should be rehabilitated by special design keratoconus lenses like Toris K and RGPCLs. Although vision rehabilitation seems better with RGPCLs, these patients prefer Toris K more because of discomfort.