Response to 'Opaque intraocular lens implantation'.

Abstract

Sir, We thank Professor MacEwen and coauthors1 for responding to our letter describing the factors influencing primary black intraocular lens (IOL) selection.2 They present the first study describing the clinical outcomes following primary implantation of a large (>7 mm optic) black IOL within the capsular bag. The Ophtec Black Ani II IOL (Ophtec BV, Groningen, The Netherlands) is a novel device produced from a material that is identical to the Artisan 201 iris-claw IOL, which has been proven to be occlusive to near infra-red (NIR) light.3 This series adds to the growing experience with black IOL implantation, and several observations warrant further comment. The mechanism of light perception following black IOL implantation is a curious phenomenon and its identification is critical to minimize the risk of treatment failure.4, 5 High rates of postoperative satisfaction are reported in patients with NIR-transmitting black IOLs,6 despite near universal postoperative light perception.5 We have suggested previously that trans-optical NIR light transmission across NIR-transmitting black IOLs may underlie intractable ghosting and treatment failure.4, 5 Such symptoms are extinguished by secondary NIR-blocking Ophtec black iris-claw IOL implantation.4, 7 Postoperative light perception in this series suggests para-optical light leakage despite a 9 mm occlusive optic, exceeding the scotopic pupil diameter. It is unlikely that formed, foveal images would result as a consequence: perceptions of ‘ghosting' following Ophtec Ani II Black IOL implantation are unlikely. Numerous black IOLs are available for clinical use, each with specific dimensions and properties that must be tailored to lens status/pupil size and the risk of retinal or optic nerve disease in each individual patient.2 We have recently described ultra-widefield imaging in a patient with a NIR-transmitting black IOL using the Heidelberg Spectralis Scanning Laser Ophthalmoscope (Heidelberg Engineering, Heidelberg, Germany). This novel discovery may drive primary implantation of NIR-transmitting black IOLs to achieve a balance of efficacy and safety – permitting detection of retinal and optic nerve pathology across the life of the implant. All black IOLs are likely to alleviate symptoms in patients with intractable diplopia and represent valid treatment modalities. However, it is essential that both patient and surgeon are informed of the risks of treatment failure and the possibility of ultra-widefield retinal imaging when a primary black IOL is selected.