Safety and efficacy of cataract surgery performed with a low-energy femtosecond laser compared with conventional phacoemulsification in Chinese patients: a randomized clinical trial.

BACKGROUND: To compare the safety and efficacy of femtosecond laser-assisted cataract surgery (FLACS) performed with the low-energy FEMTO LDV Z8 (Ziemer Ophthalmic Systems AG, Port, Switzerland) laser compared with conventional phacoemulsification (CP) in Chinese patients. METHODS: This prospective, multicenter, interventional study included 126 patients who were randomized (1:1) to undergo either FLACS or CP followed by intraocular lens (IOL) implantation between January 2019 and April 2020. The primary endpoint included the comparison of the endothelial cell loss (ECL) between the two groups at 3 months. Secondary endpoints included the comparison of cumulative dissipated energy (CDE), change in central corneal thickness (CCT) from baseline, and postoperative uncorrected and corrected distance visual acuities (UDVA and CDVA) in the two groups. RESULTS: At all postoperative time points, the FLACS group was found to be non-inferior to CP for the mean ECL (- 409.3 versus - 436.9 cells/mm2 at 3 months) and mean CDE (4.1 versus 4.5 percent-seconds). The increase in CCT was significantly lower in the FLACS group compared with the CP group at Day 7 (4.9 versus 9.2 µm; P = 0.04); however, the difference was not statistically significant at 1 and 3 months. Postoperatively, mean UDVA and CDVA were comparable between the two groups. No intraoperative complications occurred. CONCLUSIONS: Cataract surgery performed with a low-energy femtosecond laser was non-inferior to CP; however, the FLACS group had a statistically significantly lower increase in CCT at Day 7 compared with CP. Trial registration This trial is registered at ClinicalTrials.gov on May 15, 2019, with trial registration number: NCT03953053.

A novel ophthalmic viscosurgical device-free phakic intraocular lens implantation makes myopic surgery safer.

PURPOSE: To assess the efficacy and safety of a novel ophthalmic viscosurgical device-free (OVD-free) method for posterior chamber phakic intraocular lens (PIOL) implantation in myopic eyes. METHODS: In this retrospective cohort study, the medical records of myopic eyes that underwent PIOL (Implantable Collamer Lens, ICL) implantation for myopia correction at the Eye Hospital of Wenzhou Medical University between May 2015 and March 2017 were reviewed. A total of 49 eyes with complete data that met follow up requirements (2 h, 1 day, 1 week, 3 months postoperatively) were recruited. Based on the surgical techniques used, the eyes were divided into the OVD-free method group and the standard method group. The clinical data, including intraocular pressure (IOP), corrected distance visual acuity (CDVA) and spherical equivalent (SE), at each follow-up were collected for comparison. Endothelial cell loss and complications were also investigated. RESULTS: Twenty-one eyes received the standard method, and 28 eyes received the OVD-free method. A rise in IOP > 22 mmHg at 2 h was noted in 14 eyes (66.7%) in the standard group and none (0%) in the OVD-free group (p < 0.001). The rise in IOP from baseline was significantly higher at 2 h in the standard group (10.5 ± 5.2 mmHg vs. 2.2 ± 3.3 mmHg, difference: 8.3, 95% CI 5.8 to 10.8; p < 0.001). There was a significant difference in the time course of LogMAR CDVA changes between the two groups (p = 0.047). The LogMAR CDVA was significantly better in the OVD-free method group compared to the standard group at 1 day (- 0.076, 95% CI - 0.134 to - 0.018; p = 0.012), 1 week (- 0.071, 95% CI - 0.135 to - 0.007; p = 0.03), but not at 3 months (- 0.046, 95% CI - 0.107 to 0.015; p = 0.134). There was no significant difference in the time course of SE changes between the two groups (p = 0.471; p = 0.705). In the OVD-free group, mean endothelial cell loss was 4.6% at 3 months (2522 ± 281 vs. 2407 ± 226 cells/mm2, difference: -115, 95% CI - 295 to 65; p = 0.187). No complications were reported in both groups except for the early IOP elevation in the standard group during the observation period. CONCLUSIONS: The OVD-free method is safe and efficient for ICL implantation. It can be a safer method of ICL implantation compared to the standard method in that it completely eliminates ophthalmic viscoelastic devices-related complications without causing additional complications.

Age-Related Changes in Corneal Spherical Aberration.

PURPOSE: To analyze the age-related changes in corneal spherical aberration (CSA) and higher order aberrations (HOAs) and to develop a novel model to estimate the change in CSA with age. METHODS: This was a cross-sectional study of the right eyes of 3,769 patients. Anterior corneal spherical aberration (ASA), posterior corneal spherical aberration (PSA), total corneal spherical aberration (TSA), and the root mean square of corneal HOAs were measured using a Scheimpflug tomographer. Smoothed fitting curves were plotted as a function of age and the average change in spherical aberration was calculated for different ages. RESULTS: The mean magnitude of ASA, PSA, TSA, and HOAs (6 and 4 mm) were 0.270 ± 0.111, -0.144 ± 0.031, 0.228 ± 0.120, 0.453 ± 0.194, and 0.141 ± 0.075 µm, respectively. All parameters showed a statistically significant non-linear change with age. The age after which the aberrations increased at a faster rate, namely the turning points of age, were 39 years for ASA, PSA, TSA, and 6-mm HOAs (95% confidence interval [CI]: 35 to 42, 36 to 41, 36 to 42, and 35 to 56 years, respectively) and 46 years for 4-mm HOAs (95% CI: 36 to 56 years). There were significant increases in increment rates after the turning points. The average change of TSA was -0.013 µm/10 years from 18 to 39 years and 0.057 µm/10 years after 39 years. There were statistically significant correlations between ASA and TSA (r = 0.976, P < .001) and PSA and TSA (r = 0.192, P < .001), but not between ASA and PSA (r = -0.003, P = .835). CONCLUSIONS: CSA and HOAs increased non-linearly with age and became more positive after 39 and 46 years of age, respectively. Based on the increment rates and turning points of age, a novel model is provided to help calculate the value required to compensate for the increasing CSA associated with the aging cornea. [J Refract Surg. 2018;34(11):760-767.].

Posterior scleral reinforcement using genipin-cross-linked sclera for macular hole retinal detachment in highly myopic eyes.

BACKGROUND/AIMS: To investigate the surgical outcomes of posterior scleral reinforcement (PSR) using genipin-cross-linked sclera to treat macular hole retinal detachment (MHRD) in highly myopic eyes. METHODS: Nineteen patients with high myopia (19 eyes) with MHRD were treated sequentially with genipin-cross-linked PSR and were followed at least for 1 year after the surgery. The best corrected visual acuity (BCVA), axial length (AL), optical coherence tomography (OCT) outcomes and the complications were evaluated. RESULTS: Macular hole was closed in 73.7% of the eyes, foveal reattachment rate was 100%. The mean logMAR BCVA improved from 1.27±0.55 preoperatively to 0.88±0.55 postoperatively. The preoperative AL (29.88±1.97 mm) was decreased (27.73±1.84 mm) after the operation (p<0.001). CONCLUSIONS: For at least a 1-year period of follow-up, PSR with genipin-cross-linked sclera should be considered as a preferred surgical approach to treat MHRD in highly myopic eyes, especially when foveal retinoschisis is also documented.

Age-Related Changes in Corneal Astigmatism.

PURPOSE: To analyze the changes in corneal astigmatism as a function of age and develop a novel model to estimate corneal astigmatic change according to age. METHODS: This was a cross-sectional study of right eyes of 3,769 individuals. Total corneal astigmatism, keratometric astigmatism, anterior corneal astigmatism, and posterior corneal astigmatism were measured by a Scheimpflug tomographer. Smoothing fitting curves of polar values of corneal astigmatism as a function of age were drawn and average changes in corneal astigmatism at different ages were calculated. RESULTS: Two turning points of age on total corneal astigmatism were 36 and 69 years. The average change of total corneal astigmatism toward against-the-rule astigmatism was 0.13 diopters (D)/10 years from 18 to 35 years, 0.45 D/10 years from 36 to 68 years, and decreased after 69 years, mainly caused by anterior corneal astigmatism. The mean magnitude of posterior corneal astigmatism was -0.33 D and exceeded 0.50 D in 14.27% of eyes. The vectorial difference between total corneal astigmatism and keratometric astigmatism was correlated with posterior corneal astigmatism, polar value of anterior corneal astigmatism, age, and corneal higher order aberrations (r = 0.636; standard partial regression coefficients were 0.479, -0.466, 0.282, and 0.196, respectively; all P < .001). Based on the non-linear model to estimate corneal astigmatic change with age, a formula was developed to calculate recommended correction of astigmatism according to age and astigmatic type. CONCLUSIONS: The rate of change of total corneal astigmatism showed a non-linear trend toward against-the-rule astigmatism, which was low at young and old age, high at middle age, and should be taken into account when performing surgery to correct astigmatism. [J Refract Surg. 2017;33(10):696-703.].

The efficacy and safety of posterior scleral reinforcement using genipin cross-linked sclera for macular detachment and retinoschisis in highly myopic eyes.

BACKGROUND/AIMS: To evaluate the efficacy and safety of posterior scleral reinforcement (PSR) using genipin cross-linked sclera as the material to treat macular detachment and retinoschisis, both without macular hole, in highly myopic eyes. METHODS: Twenty-one patients with highly myopic eyes (24 eyes) with macular detachment and retinoschisis were treated sequentially with genipin cross-linked PSR and were followed for at least 1 year after surgery. The best-corrected visual acuity (BCVA), spherical equivalent (SE) power, axial length (AL), optical coherence tomography, and the complications were evaluated. RESULTS: The mean SE decreased from -13.81±4.67 D preoperatively to -9.64±4.86 D postoperatively, while the improvement in the logMAR BCVA values was from 1.24±0.57 before surgery to 1.03±0.57 after surgery. The preoperative AL (29.73±2.31 mm) was decreased (28.08±2.08 mm) after the operation. The retina in 21 eyes (87.5%) was successful reattached and the macular detachment was significantly decreased in two eyes; a macular hole occurred in one eye. CONCLUSIONS: For at least a 1 year period of follow-up, PSR with genipin cross-linked sclera was safe and effective to treat macular detachment and retinoschisis in high myopia when a macular hole was not present. The reinforcement effect tended to be stabilised and maintained for 6 months after treatment.