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Jan 2019 DOI 10.14302/issn.2470-0436.jos-18-2494
Stonecipher KarlCorresponding author
Clinical Associate Professor of Ophthalmology, University of North Carolina, Medical Director, The Laser Center, Greensboro, North Carolina, Medical Director, Physicians Protocol, Medical Director, Laser Defined Vision
This review is designed to look at a prospective evaluation of the use of the femtosecond laser and manual incision standard cataract surgery in one center with one surgeon focusing on visual outcomes and complications. Multiple studies support both benefits, risks, alternatives, and differences between manual capsulotomy combined with standard manual incision cataract surgery and cataract surgery employing the femtosecond laser in conjunction with routine phacoemulsification. The purpose of this study was to evaluate early postoperative outcomes using a prospective evaluation of cases from one surgeon over the course of two years from 2015-2017. The first group of cases involves 2134 eyes comparing phacoemulsification time in seconds (PT), ultrasound time in seconds (UT), and cumulative delivered energy (CDE). The second group of cases involves 1913 eyes that were Lens Opacification Classification III similar and without other ocular or lenticular abnormalities. Finally, a subgroup from the latter group (n=150) were evaluated over the course of two days and postoperative 3-hour examinations (visual acuity) were compared.
Sep 2017
Toto LisaCorresponding author
Department of Medicine and Science of Aging
Background: To evaluate cumulative dissipated energy (CDE), laser time, central corneal thickness and endothelial cell loss after two different fragmentation pattern by means of femtosecond laser-assisted cataract surgery (FLACS). Methods: Eighty eyes of 80 patients that underwent FLACS were randomized in two groups: mixed chop and dice lens fragmentation pattern (group 1 with 40 eyes) and mixed chop and cylindrical lens fragmentation pattern (group 2 with 40 eyes). Results: Cumulative dissipated energy was significantly lower in group 1 compared to group 2 (p<0.001). Postoperatively there was a decrement of endothelial cells count at the centre of the cornea in both groups compared with preoperative values with greater decrease in Group 2 (p<0.001). The thickness at the tunnel site showed a greater increase in group 2 compared to group 1 immediately after surgery (p<0.001) The thickness measured at the center of the cornea increased slightly immediately after surgery and showed a similar decrease in both groups. The increase was greater in Group 2 (p<0.001). Conclusions: Both lens fragmentation patterns were effective in nucleus disassembly. Nevertheless dice pattern was related with a lower amount of CDE and induced lower central endothelial cell loss and lower increase of corneal thickness.
May 2017 DOI 10.14302/issn.2470-0436.jos-17-1453
Zhang JieCorresponding author
Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland 1142, New Zealand.
Purpose: High intraocular pressure (IOP) is known to result in retinal ganglion cell (RGC) loss, both with chronically raised intraocular pressure (such as with glaucoma) and with acute raises in pressure (due to injury or acute angle closure). Because IOP is often raised during ocular surgery, the purpose of this study was to evaluate the effect of transient moderate IOP on retinal function, RGC survival and the expression of Connexin 43 (Cx43) and glial fibrillary acidic protein (GFAP), ubiquitously expressed central nervous system (CNS) proteins that are known to be elevated during the retinal inflammatory response to injury. Materials and Methods: Wistar rats were exposed to transient IOP at 40 mmHg for 5 or 30 minutes, and 60 mmHg for 5 minutes (via cannulation of the anterior chamber with a saline reservoir raised to a height corresponding to the desired IOP), mimicking potential IOP rises during surgery such as DSAEK and some laser procedures (LASIK and femtosecond laser cataract surgery). Separate groups of animals had IOP maintained at 10 mmHg for 5 or 30 minutes as cannulation controls, or 120 mmHg for 60 minutes as positive controls. Changes in the optic nerve and retina were assessed immunohistochemically for GFAP and Cx43 expression. Retinal function was assessed using electroretinography (ERG) recorded at baseline and 14 days after the IOP rise and compared with RGC counts. Results: Results showed that there was a differential GFAP labelling pattern observed in the anterior optic nerve in the 40 mmHg 30 minute and 60 mmHg 5 minute groups 4 hours after manipulation. Gap junction protein Cx43 was minimally up-regulated in the retina in the short-term. There was, however, minimal long-term effect on retinal function and no RGC loss. Conclusions: n conclusion, elevations of IOP that are short in duration such as those occurring during surgical procedures, do not cause significant changes long-term in retinal function or RGC survival. Key Messages: Cx43 and GFAP are known to be elevated during the retinal inflammatory response to injury. No previous study has explored the effect of moderate and relatively short increases in IOP on the initial inflammatory response. We observed a mild glial inflammatory response in the anterior optic nerve, but only a minimal up-regulation of Cx43. However, transient and moderate IOP rises did not induce long term disruption to RGC function or number as measured by electrophysiology and RGC counts, respectively. This is applicable to clinical practice, as it means the IOP elevations that occur during some surgical procedures are unlikely to be causing long term damage in retinal function or RGC survival.