The IOL-Vip System: a double intraocular lens implant for visual rehabilitation of patients with macular disease.

PURPOSE: To investigate the efficacy of a new surgical and rehabilitative procedure designed to improve vision in patients with central scotoma due to macular diseases. DESIGN: Case series of 40 consecutive surgical and rehabilitative procedures. PARTICIPANTS: Forty eyes of 35 consecutive patients with a stable central scotoma due to macular disease underwent phacoemulsification cataract surgery with the implant of the IOL-Vip System. METHODS: The IOL-Vip System consists of a biconcave high minus-power intraocular lens (IOL) in the capsular bag and a biconvex high plus-power IOL in the anterior chamber, reproducing an intraocular Galilean telescope with x1.3 magnification for distance. Selection of the candidate patients was carried out by means of a low-vision diagnostic and rehabilitative program (IOL-Vip software) that evaluates the residual visual function of patients and prognosis for visual improvement based on simulation of the postoperative condition. The software also designs the rehabilitation strategies based on preoperative and postoperative training of the preferred retinal locus. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA), evaluated by means of the Early Treatment Diabetic Retinopathy Study charts and procedure; reading magnification; and reading distance. RESULTS: All patients showed an improvement of visual acuity (VA) due to the surgical and rehabilitative procedure, confirming or exceeding the preoperative expected results. Mean postoperative BCVA was 0.77 (logarithm of the minimum angle of resolution), compared with 1.28 preoperatively. The mean postoperative best reading magnification gain was x6.2, and the mean postoperative reading distance gain was 7.66 cm. No cases of intraoperative or postoperative complications were detected, and the implant was subjectively well tolerated in both monocular and binocular procedures. CONCLUSION: In this pilot study, the IOL-Vip System was shown to be effective and apparently well tolerated in improving the vision of patients with macular disease. Best-corrected VA, reading magnification, and reading distance improved in all cases of this low-vision patient series.

CRB1 mutation spectrum in inherited retinal dystrophies.

Mutations in the Crumbs homologue 1 (CRB1) gene have been reported in patients with a variety of autosomal recessive retinal dystrophies, including retinitis pigmentosa (RP) with preserved paraarteriolar retinal pigment epithelium (PPRPE), RP with Coats-like exudative vasculopathy, early onset RP without PPRPE, and Leber congenital amaurosis (LCA). We extended our investigations of CRB1 in these retinal dystrophies, and identified nine novel CRB1 sequence variants. In addition, we screened patients with "classic" RP and classic Coats disease (without RP), but no pathologic sequence variants were found in the CRB1 gene. In total, 71 different sequence variants have been identified on 184 CRB1 alleles of patients with retinal dystrophies, including amino acid substitutions, frameshift, nonsense, and splice site mutations, in-frame deletions, and large insertions. Recent studies in two animal models, mouse and Drosophila, and in vivo high-resolution microscopy in patients with LCA, have shed light on the role of CRB1 in the pathogenesis of retinal dystrophies and its function in the photoreceptors. In this article, we provide an overview of the currently known CRB1 sequence variants, predict their effect, and propose a genotype-phenotype correlation model for CRB1 mutations.