Comparison of peripheral iridectomy methods for posterior chamber phakic intraocular lens implantation in patients with brown irides

Safety and efficacy of implantable phakic contact lens versus implantable collamer lens in myopia correction

Background

Phakic intraocular lenses (pIOLs) have proven to be excellent substitutes for excimer laser keratorefractive surgery in certain situations. We aimed to assess the efficacy and safety of two pIOLs, the implantable collamer lens (ICL V4c) versus the implantable phakic contact lens (IPCL V2), for myopic correction.

Methods

In this prospective randomized clinical trial, we allocated eligible eyes with myopia > - 6 diopters into IPCL or ICL implantation groups, each including 100 eyes of 100 individuals. Preoperative and postoperative assessments at 3, 6, and 12 months included measurements of the spherical equivalent (SE), uncorrected distance visual acuity (UCDVA), best-corrected distance visual acuity (BCDVA), intraocular pressure (IOP), maximum keratometry (K1), minimum keratometry (K2), mean keratometry (Kmean), anterior chamber depth (ACD), anterior chamber angle (ACA), and endothelial cell density (ECD).

Results

The groups had comparable demographic characteristics and baseline visual and anatomical values (all P > 0.05). The UCDVA, BCDVA, and SE of the two groups were comparable at baseline and at all postoperative follow-up examinations (all P > 0.05). Both groups experienced significant improvements in UCDVA, BCDVA, and SE at three months postoperatively (all P = 0.001), and measurements remained stable for up to 12 months. Keratometry readings were comparable between the groups over the follow-up period and remained unchanged at all visits (all P > 0.05). The ACA in the ICL group was significantly decreased at three months postoperatively (P = 0.001) and then widened significantly at 6 and 12 months (both P = 0.001). In the IPCL group, the postoperative ACA was significantly decreased at three months (P = 0.001) and was comparable to that in the ICL group (P > 0.01). However, at the 6- and 12-month postoperative visits, the ACA was significantly narrower in the IPCL group than in the ICL group (both P = 0.001). The ACD in both groups was decreased at three months postoperatively (both P = 0.001) and remained stable until the end of the study. The ECD remained comparable between the groups at all postoperative visits (all P > 0.05). We did not observe a significant ECD reduction in either group at any postoperative follow-up visit (all P > 0.05). We encountered no serious complications in either group.

Conclusions

ICL and IPCL had comparable safety and efficacy outcomes in terms of anterior chamber morphometrics, visual and refractive results, and corneal parameters. Further multicenter randomized clinical trials with longer follow-up periods, larger sample sizes, and measurement of additional anterior chamber and corneal morphometrics, vault, and other vision parameters are needed to verify these findings.

Surgical peripheral iridotomy creation during intraocular surgery by intraocular diathermy probe-a novel technique

A novel technique for the creation of surgical iridotomies using a bipolar diathermic probe is described. In a cohort comprising 19 eyes of 18 patients, a 100% patency rate was achieved, with no intra- or postoperative complications.

Preclinical Evaluation of a Cell-Based Gene Therapy Using the Sleeping Beauty Transposon System in Choroidal Neovascularization

Age-related macular degeneration (AMD) is a progressive retinal disorder characterized by imbalanced pro- and antiangiogenic signals. The aim of this study was to evaluate the effect of ex vivo cell-based gene therapy with stable expression of human pigment epithelium-derived factor (PEDF) release using the non-viral Sleeping Beauty (SB100X) transposon system delivered by miniplasmids free of antibiotic resistance markers (pFAR4). Retinal pigment epithelial (RPE) cells and iris pigment epithelial (IPE) cells were co-transfected with pFAR4-inverted terminal repeats (ITRs) CMV-PEDF-BGH and pFAR4-CMV-SB100X-SV40 plasmids. Laser-induced choroidal neovascularization (CNV) was performed in rats, and transfected primary cells (transfected RPE [tRPE] and transfected IPE [tIPE] cells) were injected into the subretinal space. The leakage and CNV areas, vascular endothelial growth factor (VEGF), PEDF protein expression, metalloproteinases 2 and 9 (MMP-2/9), and microglial/macrophage markers were measured. Injection with tRPE/IPE cells significantly reduced the leakage area at 7 and 14 days and the CNV area at 7 days. There was a significant increase in PEDF and the PEDF/VEGF ratio with tRPE cells and a reduction in the MMP-2 activity. Our data demonstrated that ex vivo non-viral gene therapy reduces CNV and could be an effective and safe therapeutic option for angiogenic retinal diseases.