Patients with posterior microphthalmos prefer soft silicone hydrogel contact lenses used in keratoconus treatment to rigid gas permeable (RGP) lenses due to their enhanced comfort, according to data reported in Eye & Contact Lens. RGPs, however, provide significantly better vision correction, according to the report.
Investigators retrospectively reviewed data from 11 patients (36% men; mean age, 20.9 years) with posterior microphthalmos who were fit with both silicone hydrogel and RGP lenses. All participants underwent axial length (AL), topographic keratometry, and best-corrected visual acuity (BCVA) measurements and rated subjective comfort levels for both lenses using a 5-point Likert scale (0, very uncomfortable; 4, very comfortable).
Mean AL was 16.01 and 15.9 mm for the right and left eyes, respectively, and flattest (K1) and steepest (K2) keratometry values were 48.6 and 49.4 diopters (D), respectively. Mean BCVA was 0.63 logarithm of the minimum angle of resolution (logMAR) prior to contact lens fitting, which improved to 0.43 logMAR with silicone hydrogel lenses (P =.018) and 0.35 logMAR with RGPs (P <.001). The RGPs provided participants with a significantly better visual acuity correction compared with the silicone hydrogel lenses (P =.008), according to the report.
However, patients reported better comfort with the silicone hydrogel lenses. Overall, 27% of study participants reported RGPs as being either comfortable or fairly comfortable compared with 96% of participants who rated silicone hydrogel lenses as either comfortable or very comfortable.
“[S]pectacles with specially designed high-index lens materials and aspheric lens is the primary choice in correction of high hyperopia, but they have many disadvantages such as increased lens thickness, increased weight because of high plus-power lenses, aniseikonia, and magnification,” according to the study authors. “Therefore, soft and rigid contact lenses are excellent choice[s] in [posterior microphthalmos], especially, in patients who are unwilling to wear spectacle for cosmesis and cannot adapt to spectacles.”
Study limitations include a small sample size, lack of a control group, and retrospective nature.
Ozcelik F, Erdogdu E, Altan C. The comparison of soft hydrocone (toris k) silicone hydrogel and rigid gas-permeable contact lenses in patients with posterior microphthalmos. Published online February 22, 2023. doi:10.1097/ICL.0000000000000978