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AIM: To evaluate the postoperative refractive prediction error (PE) and determine the factors that affect the refractive outcomes of combined pars plana vitrectomy (PPV) or silicone oil removal (SOR) with cataract surgery. METHODS: The study is a retrospective, case-series study. Totally 301 eyes of 301 patients undergoing combined PPV/SOR with cataract surgery were enrolled. Eligible individuals were separated into four groups according to their preoperative diagnoses: silicone oil-filled eyes after PPV (group 1), epiretinal membrane (group 2), macular hole (group 3), and primary retinal detachment (RD; group 4). The variables affecting postoperative refractive outcomes were analyzed, including age, gender, preoperative best-corrected visual acuity (BCVA), axial length (AL), keratometry average, anterior chamber depth (ACD), intraocular tamponade, and vitreoretinal pathology. The outcome measurements include the mean refractive PE and the proportions of eyes with a PE within ±0.50 diopter (D) and ±1.00 D. RESULTS: For all patients, the mean PE was -0.04±1.17 D, and 50.17% of patients (eyes) had a PE within ±0.50 D. There was a significant difference in refractive outcomes among the four groups (P=0.028), with RD (group 4) showing the least favorable refractive outcome. In multivariate regression analysis, only AL, vitreoretinal pathology, and ACD were strongly associated with PE (all P<0.01). Univariate analysis revealed that longer eyes (AL>26 mm) and a deeper ACD were correlated with hyperopic PE, and shorter eyes (AL<26 mm) and a shallower ACD were correlated with myopic PE. CONCLUSION: RD patients have the least favorable refractive outcome. AL, vitreoretinal pathology, and ACD are strongly associated with PE in the combined surgery. These three factors affect refractive outcomes and thus can be used to predict a better postoperative refractive outcome in clinical practice.
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BACKGROUND: The USH2A gene encodes usherin, a basement membrane protein that is involved in the development and homeostasis of the inner ear and retina. Mutations in USH2A are linked to Usher syndrome type II (USH II) and non-syndromic retinitis pigmentosa (RP). Molecular diagnosis can provide insight into the pathogenesis of these diseases, facilitate clinical diagnosis, and identify individuals who can most benefit from gene or cell replacement therapy. Here, we report 21 pathogenic mutations in the USH2A gene identified in 11 Chinese families by using the targeted next-generation sequencing (NGS) technology. METHODS: In all, 11 unrelated Chinese families were enrolled, and NGS was performed to identify mutations in the USH2A gene. Variant analysis, Sanger validation, and segregation tests were utilized to validate the disease-causing mutations in these families. RESULTS: We identified 21 pathogenic mutations, of which 13, including 5 associated with non-syndromic RP and 8 with USH II, have not been previously reported. The novel variants segregated with disease phenotype in the affected families and were absent from the control subjects. In general, visual impairment and retinopathy were consistent between the USH II and non-syndromic RP patients with USH2A mutations. CONCLUSIONS: These findings provide a basis for investigating genotype-phenotype relationships in Chinese USH II and RP patients and for clarifying the pathophysiology and molecular mechanisms of the diseases associated with USH2A mutations.