One-handed phacoemulsification with low settings

Comparative anatomical outcomes of high-flow vs. low-flow phacoemulsification cataract surgery: A systematic review and meta-analysis

Background

Phacoemulsification is an effective and widely performed technique in cataract surgery, but the comparative anatomical outcomes, including endothelial cell loss (ECL), central corneal thickness (CCT), and central macular thickness (CMT), between high-flow and low-flow phacoemulsification cataract surgery remain unclear.

Methods

This study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. Random-effects models were applied to measure pooled mean differences (MD) with 95% confidence intervals (CI) of anatomical outcomes between high-flow and low-flow phacoemulsification cataract surgery. We judged overall certainty of evidence (CoE) based on Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria.

Results

We included six randomized controlled trials (RCTs) totaling 477 participants. The meta-analysis showed similar changes associated with these two surgery types in both ECL at postoperative days 2–14 (MD: −1.63%; 95% CI: −3.73 to 0.47%; CoE: very low), days 15–42 (MD: −0.65%; 95% CI −2.96 to 1.65%; CoE: very low) and day 43 to month 18 (MD: −0.35%; 95% CI: −1.48 to 0.78%; CoE: very low), and CCT at postoperative day 1 (MD: −16.37 μm; 95% CI: −56.91 to 24.17 μm; CoE: very low), days 2–14 (MD: −10.92 μm; 95% CI: −30.00 to 8.16 μm; CoE: very low) and days 15–42 (MD: −2.76 μm; 95% CI: −5.75 to 0.24 μm; CoE: low). By contrast, low-flow phacoemulsification showed less increase in CMT at postoperative days 15–42 (MD, −4.58 μm; 95% CI: −6.3 to −2.86 μm; CoE: low).

Conclusions

We found similar anatomical outcomes, except in CMT, for both high-flow and low-flow phacoemulsification cataract surgery. Future head-to-head RCTs on visual outcomes should confirm our findings.

Systematic review registration

PROSPERO, identifier: CRD42022297036.

Effect of fluidics on corneal endothelial cell density, central corneal thickness, and central macular thickness after phacoemulsification with torsional ultrasound

Aim:

To study the relative effects of high and low fluidic parameters on endothelial cell density (ECD), central corneal thickness (CCT), and central macular thickness (CMT) after phacoemulsification with torsional ultrasound.

Settings and Design:

Prospective, randomized clinical trial based on a tertiary eye hospital.

Subjects and Methods:

The study included 65 patients in each group. Patients were randomized to either the high or the low flow group using a computerized random number table. The study was patient and examiner masked. All patients underwent phacoemulsification with torsional ultrasound. Visual acuity, ECD, CCT, and CMT were measured for all patients preoperatively at 2 weeks and 6 weeks postoperatively.

Statistical Analysis Used:

The Shapiro–Wilks test was used to assess the normality of the data. Mann–Whitney U-test with the P value set at 0.05 was used to compare the two groups.

Results:

Cumulative dissipated energy was significantly higher in the low flow group (16.44 ± 9.07 vs. 11.74 ± 6.68; P = 0.002). No statistically significant difference was noted between the two groups in the ECD, CCT, CMT, or corrected distance visual acuity at the end of 6 weeks.

Conclusions:

No significant difference was noted in the postoperative outcome between high and low flow groups. Parameters can be modified to suit the surgeon's preference, as both high and low flow parameters were found to have comparable postoperative outcomes.

Real-time dynamic intraocular pressure fluctuations during microcoaxial phacoemulsification using different aspiration flow rates and their impact on early postoperative outcomes: a randomized clinical trial

PURPOSE

To compare the impact of varying fluidic parameters on intraoperative intraocular pressure (IOP) fluctuations and postoperative outcomes.

METHODS

Prospective randomized study of 80 eyes undergoing cataract surgery that were randomly assigned to low (aspiration flow rate: 20 cc/min; bottle height: 90 cm; vacuum: 400 mm Hg) and high (aspiration flow rate: 40 cc/min; bottle height: 110 cm; vacuum: 400 mm Hg) fluidic parameter groups. Real-time dynamic intraoperative IOP was measured during nuclear fragment removal. Mean maximum and minimum IOP and percentage reduction in IOP from maximum were compared between groups. Postoperatively, the rate of change in central corneal thickness and anterior chamber inflammation at days 1 and 7, endothelial cell density at 3 months, and corneal clarity on day 1 were compared.

RESULTS

Minimum IOP in the low and high parameters groups was 35 ± 4.0 and 34.5 ± 6.8 mm Hg, respectively. Maximum IOP in the low and high parameters groups was 69 ± 3.0 and 85 ± 1.2 mm Hg, respectively (P < .002). Mean percent reduction from maximum was 59% in the high parameters group compared to 41% in the low parameters group, with the difference being statistically significant (P < .002). Rate of change in central corneal thickness was greater in the high parameters group at postoperative days 1 and 7 (P < .001). Anterior chamber inflammation and corneal clarity on the first postoperative day were significantly better in the low parameters group.

CONCLUSIONS

Higher aspiration flow rate and bottle heights are associated with high intraoperative IOPs of up to 85 mm Hg. Prolonged elevated IOP during cataract surgery was found to have more anterior segment inflammation and more edematous corneas.