Effects of Femtosecond Laser-Assisted Cataract Surgery on Macular and Choroidal Thickness in Diabetic Patients

Comparative study of FLACS vs conventional phacoemulsification for cataract patients with high myopia

PURPOSE

To compare the short-term changes in cornea, retina, and choroid of femtosecond laser-assisted cataract surgery (FLACS) with conventional phacoemulsification (CPS) in high myopia patients with cataract.

SETTING

Affiliated Hospital of Nantong University, Jiangsu Province, China.

DESIGN

Prospective single-center study.

METHODS

Demographics, ocular clinical features, ultrasound power, absolute phacoemulsification time, and effective phacoemulsification time were recorded for each patient. Endothelial cell density (ECD), central corneal thickness (CCT), corrected distance visual acuity (CDVA), intraocular pressure (IOP), center foveal thickness (CFT), subfoveal choroidal thickness (SFCT), and choroidal vascularity index (CVI) were evaluated preoperatively and at 1 week, 1 month, and 3 months postoperatively. Intraoperative parameters and intraoperative/postoperative complications were recorded.

RESULTS

97 eyes (46 eyes and 51 eyes in the FLACS and CPS groups, respectively) were included and analyzed. Effective phacoemulsification time was lower in the FLACS group compared with the CPS group ( P < .05). The increase in CCT was significantly lower in the FLACS group compared with the CPS group at 1 week and 1 month ( P < .05). CDVA and IOP were similar in both groups at the final visit ( P > .05). The ECD decreased was lower among CPS patients compared with FLACS patients. CFT, SFCT, and CVI increase in both groups but were increased more in the CPS group with high myopia patients. No serious complications occurred in either group.

CONCLUSIONS

FLACS is a more safety and effective in cataract patients with high myopia. It has advantages in effectively reducing EPT and promoting faster recovery of the cornea, macular, and choroidal thickness.

Anterior chamber cytokine production and postoperative macular edema in patients with diabetes undergoing FLACS

PURPOSE

To evaluate the effect of femtosecond laser-assisted cataract surgery (FLACS) and manual cataract surgery (MCS) on proinflammatory cytokine expression in patients with diabetes vs nondiabetic patients.

SETTING

Outpatient surgical center in Vaughan, Ontario, Canada.

DESIGN

Prospective cohort study.

METHODS

Patients with diabetes and nondiabetic patients undergoing noncomplicated MCS or FLACS were assigned into 4 cohorts: MCS nondiabetic (n = 30), FLACS nondiabetic (n = 42), MCS diabetic (n = 40), and FLACS diabetic (n = 40). Aqueous humor inflammatory mediator concentrations were evaluated at MCS onset and after femtosecond laser treatment. The presence of cystoid macular edema, anterior chamber (AC) inflammation, central retinal thickness, macular volume, and retinal microvascular changes (through optical coherence tomography angiography) were evaluated preoperatively and on postoperative day 1, week 1, month 1 (POM1), and month 3 (POM3).

RESULTS

Patients with diabetes receiving FLACS had a higher concentration of interleukin (IL)-7, IL-13, and interferon-induced protein-10 than MCS diabetic patients; they also demonstrated higher levels of vascular endothelial growth factor and lower levels of interferon (IFN)-γ, granulocyte colony-stimulating factor, and IFN-α2 compared with MCS nondiabetic patients. Macular volume appeared to be significantly higher in MCS diabetic vs MCS non-diabetic patients at POM1 and between FLACS diabetic vs FLACS nondiabetic patients at POM3. There were no other significant differences between the cohorts for any parameter.

CONCLUSIONS

FLACS use in patients with diabetes demonstrated some differences in AC cytokine expression compared with non-diabetic FLACS or diabetic patients undergoing MCS; however, there was no increase in clinical inflammatory biomarkers. FLACS seems to be a safe technique to use in patients with diabetes.

The Effects of Uneventful Phacoemulsification on Subfoveal Choroidal Thickness

INTRODUCTION

To evaluate the impacts of phacoemulsification preoperative and intraoperative factors on postoperative subfoveal choroidal thickness (SFCT).

METHODS

This prospective interventional study was conducted on patients undergoing uneventful phacoemulsification with posterior chamber intraocular lens (IOL) implantation at the private clinic Ophthalmica Eye Institute, in Thessaloniki, Greece. Forty-six eyes of 46 patients were included in the study. Operative time (OT), phacoemulsification time (PT), effective phacoemulsification time (EPT) and phacoemulsification power (PP) were recorded for each patient. All patients received dexamethasone and nepafenac drops for 4 weeks postoperatively. Choroidal thickness (CT) at five anatomical locations was measured preoperatively and at 1 week, 1 month and 3 months postoperatively.

RESULTS

Subfoveal choroidal thickness significantly increased over baseline thickness at 1 week postoperatively, returned to preoperative levels at 1 month and increased again at 3 months. Changes at 1 week and 3 months postoperatively correlated to baseline choroidal thickness (p = 0.023 and p = 0.011, respectively). Spherical equivalent (SE) inversely correlated to SFCT throughout the entire follow-up period (baseline p = 0.044, 1-week p = 0.011, 1-month p = 0.013, 3-month p = 0.018). EPT was the most significant determinant of increased SFCT at all time points (1-week p = 0.011, 1-month p = 0.01, 3-month p = 0.015). PT and PP significantly correlated to the SFCT increase at 3 months postoperatively (p = 0.033 and p = 0.043, respectively). OT was not associated with a change in SFCT at any time point (p > 0.05).

CONCLUSION

Phacoemulsification can alter choroidal thickness until at least 3 months after surgery. Preoperative and intraoperative factors, notably SE, baseline SFCT, PT, PP and especially EPT, can influence postoperative CT increase.

Effect of Phacoemulsification on Sub Foveal Choroidal and Central Macular Thickness as measured by Swept Source Optical Coherence Tomography

Objectives

To study the effect of Phacoemulsification on Sub Foveal Choroidal Thickness (SFCT) and Central Macular Thickness (CMT) as measured by Swept Source Optical Coherence Tomography (OCT).

Methods

This experimental study was conducted at Armed Forces Institute of Ophthalmology (AFIO), Rawalpindi from April 2021 to February 2022. One hundred eyes of 100 patients with age related cataract underwent uneventful phacoemulsification surgery. Pre-operative SFCT and CMT was measured and compared with SFCT and CMT at one week, one month and three months after surgery using swept source OCT.

Results

Mean age of study population was 56.76±8.31 years. Out of 100 patients, 46 (46%) were males and 54 (54%) were females. Mean pre-operative CMT, one week, one month and three months post-operative CMT was 233.95±9.46 μm, 232.88±8.59 μm, 230.38±10.62 μm and 230.67±7.55 μm respectively. Mean pre-operative SFCT, one week, one month and three months post-operative SFCT was 337.14±8.41 μm, 339.14±9.63 μm, 339.39±11.96 μm and 351.39±9.19 μm respectively. The difference of mean change in CMT from baseline at one week, one month and three months post-operatively was not statistically significant. The difference of mean change in SFCT from baseline at one week and one month post-operatively was not statistically significant. However, the difference of mean change in SFCT from baseline at three months post-operatively was statistically significant (p<0.05).

Conclusion

Uneventful phacoemulsification surgery does not have any effect on central macular thickness, however there is a significant increase in subfoveal choroidal thickness at three months after surgery.

Dexamethasone intravitreal implant along with femtosecond laser assisted cataract surgery in patients with diabetic macular edema and cataract

PURPOSE

To assess the safety and efficacy of intraoperative dexamethasone intravitreal (DEX) implant in patients with diabetic macular edema (DME) undergoing femtosecond laser assisted cataract surgery (FLACS).

METHODS

In this single-center retrospective study, the charts of patients who underwent combined FLACS and DEX implant in the previous three months were reviewed. Primary outcome measures were ocular complications; secondary outcome measures were the change of best-corrected visual acuity (BCVA) and central retinal thickness (CRT).

RESULTS

20 eyes of 20 patients were included. None developed intraoperative or postoperative complications. Mean BCVA was 20/120 (logMAR, 0.78 ± 0.31) at baseline and improved significantly to 20/63 (logMAR, 0.52 ± 0.24; p = 0.01), 20/58 (LogMAR, 0.48 ± 0.28; p < 0.001) and to 20/58 (LogMAR, 0.48 ± 0.31; p < 0.001) at month 1,2 and 3, respectively. A mean improvement of 0.30 LogMAR was recorded at month 1 and 3. Mean CRT decreased significantly from 416.6 ± 76.1 μm at baseline to 322.4 ± 46.4 μm (p < 0.001), to 300.7 ± 29.7 μm (p < 0.001), and to 319.8 ± 54.7 μm (p < 0.001) at month 1,2 and 3, respectively. Comparing to the 1-month follow-up, the largest mean reduction in CRT (112.4 ± 68.9 µm) was observed at month 2 (p = 0.001). Fourteen patients (70%) had an improvement of CRT over the first 2 months followed by a recurrence of edema at month 3.

CONCLUSION

DEX implant following FLACS seems to be a safe and effective approach for patients with coexisting cataract and DME.

Corneal Endothelial Cell Changes After Femtosecond Laser-Assisted Cataract Surgery in Diabetic and Nondiabetic Patients

OBJECTIVE

To compare corneal endothelial cell changes after femtosecond laser-assisted cataract surgery (FLACS) in diabetic and nondiabetic patients.

METHODS

This retrospective study included patients with cataract who underwent FLACS performed by a single surgeon between August 2018 and November 2020. Changes in corneal endothelial cell density (ECD), hexagonality, coefficient of variation in cell size (CV), and central corneal thickness (CCT) at baseline and at the 1-month and 3-month postoperative follow-ups were investigated by dividing the patients into diabetic and nondiabetic groups.

RESULTS

We included 75 patients (60% men, mean age: 57.7±11.4 years, range: 27-80 years) in the analysis: 31 diabetic patients (64% men, mean age: 58.7±11.9 years, range: 27-79 years) and 44 nondiabetic patients (56% men, mean age: 57.1±11.3 years, range: 34-80 years). No differences were observed between the two groups as regards preoperative and intraoperative parameters, the mean postoperative ECD, hexagonality, and CV. At 1 month postoperatively, the CCT was significantly greater in the diabetic group (P=0.034); however, at 3 months, there was no significant difference between the two groups (P=0.927).

CONCLUSIONS

Changes in postoperative corneal endothelial cells were comparable between patients with and without diabetes after FLACS. Femtosecond laser-assisted cataract surgery seems to cause less damage to the corneal endothelium in diabetic patients because it uses less phacoemulsification energy.

Low-Intensity Femtosecond Radiation Activates the Natural Defenses of Mice in vivo

The possibility of induction of cytogenetic damage in the bone marrow, changes in the cellularity of lymphoid organs and blood composition in mice irradiated with low-intensity femtosecond laser radiation at a power flux density of 5.1, 10.4, and 52 mJ/cm2 (0.5 mW for 5, 10, and 50 s) in vivo was shown. Using the radiation adaptive response test (0.1 Gy + 1.5 Gy), it was found that, when mice were exposed to femtosecond laser radiation in high doses, the body's natural defenses were activated in the same narrow range of energy flux density (2-16 mJ/cm2) as in the case of X-ray irradiation in a dose of 0.1 Gy (4 mJ/cm2). The data obtained suggest a similar mechanism of activation of the body's natural defense upon exposure to low doses of both ionizing and non-ionizing radiation.