gms | German Medical Science

Purpose: Intraocular lens (IOL) calcification can only be treated by removing the clouded lens. Since explantation bears the risk of complications, it is often deferred until the patient finds the symptoms intolerable. Visual acuity may be only minimally affected, though. In this study, we assessed the impact of homogeneous opacification on optical quality.

Methods: We analyzed 10 explanted IOLs (Oculentis GmbH) with homogenous (primary) opacification. Wavefront aberrations were obtained with a SHSOphthalmic device (Optocraft GmbH), which features a Hartmann-Shack sensor. We detected light scattering with a C-Quant instrument (Oculus GmbH) and expressed it as a straylight parameter. The Root-Mean-Square (RMS) of higher-order aberrations was compared. The effect of homogeneous calcification on image quality was assessed through the Strehl ratio (SR).

Results: At 2mm, 3mm, and 4mm, the mean RMS (±standard deviation) was 0.033μm (±0.026μm), 0.044μm (±0.027μm), and 0.087μm (±0.049μm), respectively. The mean SR value was 0.81 (±0.15) at 3mm, with 4 IOLs showing a nearly diffraction-limited performance. By contrast, increased straylight was found in all opacified IOLs with a mean value of 150.2 ±56.3 deg2/sr at 3mm.

Conclusion: We demonstrated that homogeneous opacification induces higher-order aberrations. However, the RMS remained low, which resulted only in a slight reduction of the optical quality. On the other hand, we found a severe straylight elevation, which may result in photic phenomena, such as glare and subjective complaints, despite good visual acuity.