Confounding sizing in posterior chamber phakic lens selection due to white-to-white measurement bias

Purpose: To assess the agreement in the white-to-white (WTW) measurement with two different devices, the reproducibility and the probability of confusing sizing (PCS) in selecting a different implantable collamer lens (ICL). Study Design: Retrospective observational case series. Methods: Images of 192 eyes were captured with both devices. The WTW was measured automatically (OA) and manually (OM) with the Orbscan and Keratograph (KA and KM) by one examiner who repeated a total of four measures. A second examiner conducted a single manual measure for each device over the same image. The ICL sizing was computed for each measure of WTW and the PCS was calculated as the percentage of cases for which the confronted or repeated measure resulted in a different size of the ICL. The critical WTWs with highest PCS were identified. Results: KM overestimated the WTW versus OM in 0.13 ± 0.18 mm (P < 0.001) but not in the automated method comparison, 0.01 ± 0.19 mm (P = 0.58). Inter-examiner reproducibility (R) was higher with OM than with KM, and the intra-examiner R decreased with the average of two measures in both cases. The PCS was higher with the increase of mean differences, the limits of agreement (LoAs), and R. WTWs from 11.1 to 11.2 mm, 11.6 to 11.7 mm, and 12.3 to 12.4 mm resulted in higher PCS. Conclusion: The mean difference is not enough to apply conversions between devices and the LoAs and R should be considered. Special attention should be taken for WTWs with higher PCS.

Modified technique and clinical application of central hole ICL implantation for 2a / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To explore the application of improved skills in central hole ICL V4c implantation and its clinical efficacy. <p>METHODS: This study included 141 eyes of 72 patients with myopia from September 2015 to August 2016. An implantable contact lens with a central hole(ICL V4c)was inserted by improved surgical skills including single 2.8mm clear corneal incision, no anterior chamber viscoelastics before ICL implantation. The intraocular pressure(IOP)was measured at the early stage within 6h after operation. The visual acuity, diopter, intraocular pressure and corneal endothelial cell density were observed after operation and follow up 2a. <p>RESULTS: ICL V4c was implanted successfully in all patients by this improved skills and fine clinical results were achieved. Elevated IOP is possible at early stage post-operation, especially within 2h after operation. 95.7% had normal IOP 6h after operation. The postoperative IOP was stable within 2a follow-up period. The cumulative corneal endothelial loss rates of 6mo, 1a and 2a were 4.70%, 7.59% and 9.63% respectively. There was no complications such as subcapsular cataract during the 2a follow-up period.<p>CONCLUSION: The improved skills used in our study is safe and feasible.

Visual quality in posterior chamber phakic intraocular lens implantation / 国际眼科杂志(Guoji Yanke Zazhi)

@#Posterior chamber intraocular lens implantation was effective for correcting refractive errors. More scientific studies about subjective visual quality(visual acuity, contrast sensitivity)and objective visual quality(wave front aberration, point spread function, Strehl ratio, modulmion transfer function)had showed that the improvement of subjective visual acuity was accompanied with the improvement of objective visual acuity after phakic intraocular lens implantation. However, the complications, such as anterior subcapsular cataract, glaucoma and decomposition of corneal endothelium needed to be long-term followed up. This article summarized the visual quality research after posterior chamber phakic intraocular lens implantation.

Short-term efficacy of posterior chamber phakic intraocular lens implantation for moderate to high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To evaluate the short-term efficacy of posterior chamber phakic intraocular lens implantation for moderate to high myopia.METHODS:Fifty-three eyes of 27 patients with moderate to high myopia (-3.25 to-21.5D) were received posterior chamber phakic intraocular lens implantation with 2.8mm clear corneal incision.Changes of visual acuity, intraocular pressure(IOP), counts of endothelial cells and surgically induced astigmatism at 1mo after surgery were observed.RESULTS:The preoperative best corrected visual acuity (BCVA LogMAR) were 0.05±0.18, the postoperative BCVA at 1d were 0.02±0.14, the postoperative BCVA at 1wk were-0.05±0.11, the postoperative BCVA at 1mo were-0.07±0.10.The postoperative BCVA were statistically significant differences in different time(P<0.05).The preoperative endothelial cell count was 2932.5±270.8/mm2, the postoperative endothelial cell count at 1d was 2917.1±299.0/mm2;the postoperative endothelial cell count at 1wk was 2902.5±288.6/mm2;the postoperative endothelial cell count at 1mo was 2855.3±284.2/mm2.The postoperative endothelial cell count was not statistically significant differences in different time.The preoperative IOP was 15.8±2.5mmHg;the postoperative IOP at 1d was 15.3±2.9mmHg;the postoperative IOP at 1wk was 17.4±5.8mmHg;the postoperative IOP at 1mo were 15.8±2.6mmHg.The preoperative IOP was significantly different compared with postoperative IOP at 1d, 1wk and 1mo.The postoperative IOP at 1d and 1wk were statistically significant differences (P<0.05).The surgically induced astigmatism at 1d was 0.74±0.39D;the surgically induced astigmatism at 1wk was 0.57±0.28D;the surgically induced astigmatism at 1mo was 0.44±0.21D.The postoperative IOP were statistically significant differences in different time (P<0.05).The preoperative anterior chamber depth was 3.26±0.25mm;the postoperative central vault at 1d were 654.5±345.2μm;the postoperative central vault at 1mo were 683.0±211.7μm.The postoperative central vault were significantly different between that at 1d and 1mo after operations.Operations went without serious complications.CONCLUSION:Posterior chamber phakic intraocular lens implantation for moderate to high myopia were safe, effective and predictability.But long-term effect remains needed to be further follow-up.

Clinical observation of implantable collamer lens in treatment of super high myopia / 局解手术学杂志

Objective To investigate the clinical effect of implantable collamer lens ( ICL) in the treatment of super high myopia. Methods 20 patients with high myopia were given ICL,and changes in patients with visual acuity,intraocular pressure and corneal endothe-lial cells,and surgery-related complications and outcome were observed. Results Before surgery,the visual acuity of patients was (0. 10±0. 05),and postoperative (0. 60±0. 20),the difference was statistical significance(P<0. 05);the intraocular pressure and corneal endothe-lial cells of patients did not change significantly after surgery,with less postoperative complications. Conclusion The ICL has a very signifi-cant effect in the treatment of super high myopia,which can help to improve the patient's quality of life,and it is worthy of wide promotion and application.