Opaque intraocular lens implantation

Correspondence: CK Patel The Oxford Eye Hospital, West Wing, John Radcliffe Hospital, Headley Way, Headington, Oxford, OX3 9DU, United Kingdom Tel +44 18 6523 4736 Fax +44 18 6524 0097 Email [email protected] We read with great interest the recent article by Lee et al, who described their clinical experience with three patients who underwent primary implantation of Morcher (Stuttgart, Germany) occlusive intraocular lenses (IOLs) across a variety of neuroophthalmic indications. We hope to offer some further insight into these clinical observations in the context of our ongoing research into occlusive IOLs. We feel such a discussion may be of benefit to ophthalmologists managing this group of patients. Lee et al describe a patient with intractable diplopia who underwent clear lens extraction with implantation of an 80D 6 mm Morcher occlusive IOL, followed by a second procedure to augment occlusion within the scotopic pupillary margin using two Morcher partial aniridia implants (50C) and a third procedure to implant a Morcher 80D occlusive IOL with a 10 mm optic. This patient was able to perceive light despite four anatomically continuous occlusive intraocular devices spanning the pupillary aperture. The authors interpret this to suggest the route of postoperative light entry into the eye must be across the intact sclera. Our research indicates a more likely mechanism to explain this perception of light, an understanding of which may be critical to a satisfactory outcome in this group of patients. We initially reported the serendipitous discovery of successful macular imaging using a combined confocal laser scanning ophthalmoscopy/optical coherence tomography imaging system through the Morcher 85F occlusive IOL implanted in a patient with visual confusion. We analyzed the transmission spectra of all Morcher occlusive IOLs to clarify the mechanism behind this observation, discovering that whilst wavelengths of light below 740 nm were occluded entirely by the occlusive IOL, there was an exponential increase in light transmission above 750 nm, with approximately 50% of light transmitted at 780 nm and 100% of light transmitted at wavelengths longer than 820 nm through the Morcher occlusive IOL. This explained the acquisition of high quality images with combined confocal laser scanning ophthalmoscopy/optical coherence tomography imaging systems which use a near infrared superluminescent diode as their light source. Near infrared light activates photopigments in long wavelength red cone photoreceptors, resulting in light perception, provided that the stimulus of light is sufficiently bright. Photopic conditions and sources of light with a rich near infrared component are likely to be perceived by patients with near infrared-transmitting occlusive IOLs produced by Morcher. This near infrared window of transmission is the likely primary mechanism underlying refractory light perception in patients implanted with Morcher Dovepress