scholarly journals Optical Quality after Posterior Chamber Phakic Implantation of an Intraocular Lens with a Central Hole (V4c Implantable Collamer Lens) under Different Lighting Conditions

2019 ◽  
Author(s):  
Tianrui He ◽  
Yi Zhu ◽  
Jibo Zhou

Abstract Background The current study compared optical quality before and after implantation of a posterior chamber phakic intraocular lens with a central hole [V4c implantable collamer lens (ICL)] under bright and dark lighting conditions by means of the Optical Quality Analysis System™ (OQAS; Visiometrics, Terrassa, Spain). Methods This prospective study involved 91 eyes of 46 consecutive patients undergoing implantation of a V4c ICL (15 males and 31 females). The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and predicted visual acuities (PVAs; 100%, 20%, and 9%), under different lighting conditions, were measured before and 1 week, 1 month, and 3 months after surgery. Results All optical parameters showed significant improvements, at all time points, under dark condition after surgery. We observed no significant changes in PVA 9% at 1 week (P=0.12) or 1 month after surgery (P=0.08) under light condition; but all other postoperative parameters improved significantly. Comparing the two lighting conditions, the OSI decreased more under dark conditions at 1 week (P=0.02), 1 month (P=0.004), and 3 months (P=0.002), but there was no significant difference in any other parameter. In addition, patients were divided into a high myopia group (group H) and a super-high myopia group (group S), the group S improved significantly more than group H in all parameters, under both bright and dark conditions. Conclusions V4c ICL implantation improved optical quality under both bright and dark lighting conditions, and had a better ability to reduce the extent of scattering in the dark. Furthermore, group S achieved greater improvement in visual quality, which should be considered by physicians before surgery.

2019 ◽  
Author(s):  
Tianrui He ◽  
Yi Zhu ◽  
Jibo Zhou

Abstract Background The current study compared optical quality before and after implantation of a posterior chamber phakic intraocular lens with a central hole [V4c implantable collamer lens (ICL)] under bright and dark lighting conditions by means of the Optical Quality Analysis System™ (OQAS; Visiometrics, Terrassa, Spain). Methods This prospective study involved 91 eyes of 46 consecutive patients undergoing implantation of a V4c ICL (15 males and 31 females). The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and predicted visual acuities (PVAs; 100%, 20%, and 9%), under different lighting conditions, were measured before and 1 week, 1 month, and 3 months after surgery. Results All optical parameters showed significant improvements, at all time points, under dark condition after surgery. We observed no significant changes in PVA 9% at 1 week (P=0.12) or 1 month after surgery (P=0.08) under light condition; but all other postoperative parameters improved significantly. Comparing the two lighting conditions, the OSI decreased more under dark conditions at 1 week (P=0.02), 1 month (P=0.004), and 3 months (P=0.002), but there was no significant difference in any other parameter. In addition, patients were divided into a high myopia group (group H) and a super-high myopia group (group S), the group S improved significantly more than group H in all parameters, under both bright and dark conditions. Conclusions V4c ICL implantation improved optical quality under both bright and dark lighting conditions, and had a better ability to reduce the extent of scattering in the dark. Furthermore, group S achieved greater improvement in visual quality, which should be considered by physicians before surgery.


2020 ◽  
Author(s):  
Tianrui He ◽  
Yi Zhu ◽  
Jibo Zhou

Abstract Background: The current study compared optical quality before and after implantation of a posterior chamber phakic intraocular lens with a central hole [V4c implantable collamer lens (ICL)] under bright and dark lighting conditions by means of the Optical Quality Analysis System™ (OQAS; Visiometrics, Terrassa, Spain). Methods: This prospective study involved 91 eyes of 46 consecutive high myopia patients (15 males and 31 females, average spherical equivalent -10.50±0.33D) undergoing implantation of a V4c ICL. The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and predicted visual acuities (PVAs; 100%, 20%, and 9%), under different lighting conditions, were measured before and 1 week, 1 month, and 3 months after surgery. Results: All optical parameters showed significant improvements, at all time points, under dark condition after surgery. We observed no significant changes in PVA 9% at 1 week (mean value 0.539, P=0.12) or 1 month after surgery (mean value 0.573, P=0.08) under bright condition; but all other postoperative parameters improved significantly. Comparing the two lighting conditions, the OSI decreased more under dark conditions at 1 week (P=0.02), 1 month (P=0.004), and 3 months (P=0.002), but there was no significant difference in any other parameter. In addition, patients were divided into super high myopia (group S, spherical equivalent greater than -10 D) and high myopia (group H, spherical equivalent from -6 D to -10 D), the group S improved significantly more than group H in all parameters, under both bright and dark conditions. Conclusions: V4c ICL implantation improved optical quality under both bright and dark lighting conditions, and had a better ability to reduce the extent of scattering in the dark. Furthermore, group S achieved greater improvement in visual quality, which should be considered by physicians before surgery.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xiao-ling Jiao ◽  
Jun Li ◽  
Zhe Yu ◽  
Ping-hui Wei ◽  
Hui Song

Abstract Background To compare visual performance between the iris-fixated phakic intraocular len (pIOL) and implantable collamer len (ICL) to correct high myopia. Methods Twenty-four eyes underwent iris-fixated pIOL implantation and 24 eyes underwent ICL implantation. At the 6-month follow-up, the best-corrected visual acuity (BCVA) and uncorrected distance visual acuity (UDVA) were compared between the iris-fixated pIOL and ICL groups. The objective scatter index (OSI), modulation transfer function (MTF) cutoff, and ocular aberrations were performed to evaluate postoperative visual quality between the two groups. Results No significant difference was found in UDVA, BCVA, and spherical equivalent between the iris-fixated pIOL and ICL groups (P > 0.05). Six months after surgery, the following values were significantly higher in the ICL group than in the iris-fixated pIOL group: MTF cutoff, strehl ratio and optical quality analysis system values at contrasts of 9 %, 20 %, and 100 % (P < 0.01). The OSI in the iris-fixated pIOL group was higher than in the ICL group 6 months after surgery (P < 0.01). All high-order aberrations were slightly more severe in the iris-fixated pIOL group than in the ICL group 6 months after surgery, although only trefoil (P = 0.023) differed significantly in this regard. Conclusions Both iris-fixated lenses and ICLs can provide good visual acuity. ICLs confer better visual performance in MTF-associated parameters and induce less intraocular light scattering than iris-fixated pIOLs.


Medicine ◽  
2016 ◽  
Vol 95 (36) ◽  
pp. e4641 ◽  
Author(s):  
Xinfang Cao ◽  
Weiliang Wu ◽  
Yang Wang ◽  
Chen Xie ◽  
Jianping Tong ◽  
...  

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Ying Tang ◽  
Jian Ye

Purpose. To evaluate the efficacy of phakic posterior chamber intraocular lens with a central hole (ICL V4c) in treating patients with moderate to high myopia. Methods. PubMed, Embase, Cochrane Library, Clinical Trial, China Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), and China Science Periodical Database (CSPD) were searched online. The search included publications from the building of the library until December 2018. All randomized controlled trials containing moderate to high myopia treated by phakic posterior chamber intraocular lens with a central hole were collected. Literature search, screening literature, data extraction, and quality evaluation were independently performed by two reviewers. Meta-analysis was performed using RevMan 5.3 software. Results. Meta-analysis results based on five randomized controlled trials showed that ICL V4c and ICL without a central hole had similar UCVA results (SMD = 0.08, 95% CI (−0.71, 0.88), P=0.84), SE (SMD = −0.18, 95% CI (−0.52, 0.15), P=0.29), BCVA (SMD = −0.27, 95% CI (−0.93, 0.40), P=0.43), and IOP (SMD = 0.03, 95% CI (−0.24, 0.30), P=0.84), and the difference was not statistically significant. In addition, no complications that could jeopardize vision occurred. Conclusions. Implanting ICL V4c in patients with moderate to high myopia is safe and effective.


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