Opaque intraocular lens implantation

Abstract

Sir, Methodological remarks concerning the recent metaanalysis on the effect of intravitral bevacizumab in central serous chorioretinopathyWe read with great interest the recent meta-analysis by Chung et al, 1 which reached important conclusions about the effect of intravitral bevacizumab in central serous chorioretinopathy; nevertheless, some methodological issues need to be addressed concerning this meta-analysis. 1 Specifically, the authors state that 'The mean difference and SD at the 6-month follow-up were calculated from the data in the included studies.' This seems an intriguing statement that should be further clarified by the authors to substantiate the validity of the meta-analysis and guarantee the reproducibility of their results. The included studies presented mean ± SD at baseline and at the 6-month time point; the SD of the difference (with the latter representing a new measure) was not provided by the included articles.Given that the variance of a an A-B difference inherently necessitates knowledge about the covariance (A, B), any attempt to estimate the SD of the difference would imply assumptions about the covariance; the latter is not negligible and seems of corollary importance in light of the longitudinal nature of the baseline-6-month comparison. Therefore, the authors should disclose their assumptions regarding the calculation of covariance and provide the relevant formulas with the corresponding statistical references supporting their approach; critical discussion of any limitations potentially stemming from such assumptions would be of interest.An alternative way would be contact with the authors of each study, asking them to calculate de novo the difference and provide the meta-analysts with the exact SD data. Nevertheless, Chung et al did not provide any statement disclosing contact with the authors of individual studies.In conclusion, thorough clarification of the methods used by Chung et al 1 seems desirable, so as to further solidify the validity of their approach. Reliable calculation of variance often represents a challenging notion in the field of meta-analysis. Conflict of interestThe authors declare no conflict of interest. We appreciate the interest of Sergentanis and Chatziralli in our published manuscript, 'Lack of positive effect of intravitreal bevacizumab in central serous chorioretinopathy: meta-analysis and review.' 1 They have addressed methodological issues concerning metaanalysis because the SD of difference was not provided in the manuscript. We absolutely agree that it would have been more meaningful meta-analysis if we contacted the authors of each study, asking them to calculate de novo the difference as Sergentanis and Chatziralli have rightly pointed out. Alternatively, Hedges g formula for pooled SD was used to estimate difference SD. And then, paired SD was calculated, as follows, pooled SD × sqrt(2 × 1 − r)).Although our meta-analysis failed to verify the positive effect of IVB in CSC, the outcome of this treatment is still unknown owing to many limitations,...

Implantation of the Black Artisan Iris-Claw Intraocular Lens: A Case Series

“…Our results compare with a recent case series described by Gong et al [10] of 5 (of 6) patients being implanted with a custom-made Ophtec 0,0 dpt black polycarbonate Ani II (no hole; 9 mm optic diameter) IOL into the capsular bag. This IOL has the same near-infrared-blocking properties as the black Artisan iris-claw IOL used in our series and provides total light occlusion; regardless, 4 patients had variable light perception postoperatively [10].…”

Don't be afraid of the dark - OCT angiography through a black intraocular lens

“…The lens Ani II (Ophtec BV), manufactured on the same material as the Artisan® 201, is currently the only IOL on the market without a near-infrared window and has a mixed record of eliminating light perception. 10 Refractory light perception in the presence of an near-infrared light blocking IOL may be based on para-optical light leakage 11 or transmission of light through the intact sclera. 2 In the present case of a Morcher IOL with a near-infrared window, all three mechanisms discussed for light perception would be conceivable in principle.…”