Corneal biomechanical properties changes after coaxial 2,2-mm microincision and standard 3,0-mm phacoemulsification

AIM: To compare the changes in corneal biomechanics measured by ocular response analyzer(ORA) after 2.2-mm microincision cataract surgery and 3.0-mm standard coaxial phacoemulsification.· METHODS: The prospective nonrandomized study comprised eyes with cataract that had 2.2-mm coaxial microincision or 3.0-mm standard incision phacoemulsification. The corneal hysteresis(CH), corneal resistance factor(CRF), corneal-compensated intraocular pressure(IOPcc) and Goldmann-correlated intraocular pressure(IOPg) were measured by ORA preoperatively and at 1d, 1-, 2-, 3- and 4-week postoperatively. Results were analyzed and compared between groups.· RESULTS: In both groups, CH decreased in the immediate postoperative period(P <0.05), returned to the preoperative level at one week(P =0.249) in the 2.2-mm group, and at two weeks in the 3.0-mm group(P =0.264);there was no significant change in CRF values. In 2.2-mm group, mean IOPcc and IOPg increased at 1d postoperatively(both P <0.05), and returned to preoperative level at one week(P =0.491 and P =0.923, respectively).In 3.0-mm group, mean IOPcc and IOPg increased at 1d and 1wk postoperatively(P =0.005 and P =0.029,respectively), and returned to preoperative level at 2wk(P =0.347 and P =0.887, respectively).· CONCLUSION: Significant differences between preoperative and postoperative corneal biomechanical values were found for CH, IOPcc and IOPg. But the recovery time courses were different between the twogroups. The 2.2-mm coaxial microincision cataract surgery group seemed recovery faster compared to the3.0-mm standard coaxial phacoemulsification group.

Evaluation of macular vessel density changes after vitrectomy with silicone oil tamponade in patients with rhegmatogenous retinal detachment

AIM:To evaluate macular microvasculature changes in eyes after pars plana vitrectomy(PPV)and intraocular silicone oil(SO)tamponade for macula-off rhegmatogenous retinal detachment(RRD)using optical coherence tomography angiography(OCTA).METHODS:Totally 19 eyes(19 patients)with maculaoff RRD who underwent PPV and intraocular SO tamponade were retrospectively reviewed.The parafoveal superficial capillary plexus(SCP)vessel density(VD),deep capillary plexus(DCP)VD,choriocapillaris plexus(CCP)VD,and foveal macular thickness were evaluated using OCTA throughout 16 wk postoperatively.The values of healthy fellow eyes were used as control.RESULTS:The parafoveal SCP,DCP,and CCP VDs were significant increased over time in RRD eyes during the 12 wk postoperatively,then decreased at 16 wk postoperatively(all P<0.01).The ratios of RRD eyes and fellow healthy eyes(r/f ratios)of the SCP and DCP VDs were lower than those of the CCP VD postoperatively(all P<0.05).There were not significant differences in the r/f ratios between SCP and DCP VDs postoperatively(all P>0.05).CONCLUSION:The parafoveal SCP,DCP,and CCP VDs gradually recover over time after PPV surgery with SO tamponade.Long-time SO tamponade might decrease postoperative macular VDs.Compared to parafoveal CCP VD,the parafoveal SCP and DCP VDs were more vulnerable in RRD eyes postoperatively.