Effect of Anterior Chamber Instability during Phacoemulsification Combined with Intraocular Lens Implantation

Vitreous-lens interface changes after cataract surgery using active fluidics and active sentry with high and low infusion pressure settings

PURPOSE

To determine whether the infusion pressure used during phacoemulsification may have a detrimental effect on the anterior hyaloid membrane barrier (AHMB) in a pressure fluctuation-free environment using diagnostic spectral-domain optical coherence tomography (SD-OCT) postoperatively.

SETTING

Tandil Eye Clinic, Tandil, Buenos Aires, Argentina, and Centro Oftalmológico Dr. Charles, CABA, Buenos Aires, Argentina.

DESIGN

Prospective, randomized, multicenter, experimental, and double-masked study.

METHODS

Phacoemulsification with intraocular lens implantation was performed in all patients with the Centurion Vision System equipment with active fluidics and active sentry. Patients were randomly assigned to configuration 1 or 2. Configuration 1 had intraocular pressure (IOP) 30 mm Hg and configuration 2 IOP 80 mm Hg. Inclusion criteria were axial length >22 mm and <25 mm, age older than 50 and younger than 70 years, and complete adhesion of AHMB.

RESULTS

80 eyes of 80 patients were included. Berger space was identified in 17 cases (42.5%) of group 2 and 3 cases (7.5%) of group 1 postoperatively using SD-OCT. A statistically significant relationship was established using Fisher exact test ( P = .0003). Postoperatively, we observed posterior vitreous detachment changes in only 1 patient (1.25%) during the 3 months of follow-up ( P = .5). According to the Wong-Baker FACES Scale, the patient's subjective perception was better for the low infusion pressure group ( P = .0001, Fisher exact test).

CONCLUSIONS

Phacoemulsification with high infusion pressure can change the vitreous-lens interface. Positive Berger space after phacoemulsification is a biomarker of this change and can occur in eyes without risk factors. Incidence is directly related to the infusion pressure used.

Swab Pressing vs Stromal Hydration to Prevent Incision Leakage and Transient Collapse of Anterior Chamber in Phacoemulsification: A Randomized Clinical Trial

Importance

During phacoemulsification, incision leakage and the subsequent anterior chamber collapse often occur after the withdrawal of the handpiece, which cannot be prevented by current sealing techniques. A new technique called swab pressing is proposed here to apply pressure with a cotton swab to seal the incision immediately, but efficacy remains unknown.

Objective

To determine if swab pressing is noninferior to stromal hydration, the current practice, in sealing incisions in phacoemulsification for age-related cataract.

Design, Setting, and Participants

This noninferiority randomized controlled clinical trial was conducted between February 2022 and September 2022 at the Zhongshan Ophthalmic Center, Guangzhou, China. Patients aged 60 to 90 years with age-related cataract were enrolled.

Interventions

Participants were randomly assigned (1:1) to receive swab pressing or stromal hydration. All surgeries were performed by a single experienced surgeon who was unmasked to the assignment.

Main Outcomes and Measures

The proportion of closed clear corneal incisions evaluated using intraoperative optical coherence tomography.

Results

A total of 126 eyes of 126 participants were randomized into the swab pressing group (63 [50%]) and stromal hydration group (63 [50%]). The mean (SD) age of participants was 69.2 (6.14) years and 70.1 (7.67) years in the pressing and stromal hydration groups, respectively. A total of 39 participants (61.9%) in the pressing group and 35 (55.6%) in the modified group were female. The proportion of closed incisions was 96.8% (61 of 63) in the swab pressing group and 93.7% (59 of 63) in the stromal hydration group. Noninferiority was met, as the lower 95% CI of -5.83 percentage points was greater than the prescribed noninferiority margin of -6.60 percentage points (difference, 3.17 percentage points; 95% CI, -5.83 to 12.18 percentage points). The rate of anterior chamber collapse (pressing: 0 of 63 vs stromal hydration: 35 of 63 [55.6%]; P < .001) was lower in the swab pressing group. There were no differences between the 2 groups in the proportion of closed incisions and central anterior chamber depth at postoperative hour 1 and day 1.

Conclusions and Relevance

In this study, swab pressing was noninferior to stromal hydration in sealing clear corneal incisions in phacoemulsification for age-related cataract. While this trial involved only 1 surgeon who was not masked to the interventions, the results suggest that swab pressing is feasible and further investigations would be warranted to determine if it prevents the intraoperative transient collapse of anterior chamber or affects visual acuity outcomes.

Trial Registration

ClinicalTrials.gov Identifier: NCT05242653.

Twist Technique to Stop Fluid Leakage and Fixate the Eye During Bimanual Cortex Removal in Phacoemulsification

Leakage of fluid through the side port during aspiration of the cortex leads to instability of the anterior chamber. In addition, eye movement may cause an unintended pulling of the irrigation probe out of the corneal wound resulting in collapsing of the anterior chamber. Both situations could pose a challenge to the surgeon and increase the risk of serious intraoperative complications. Therefore, we describe a simple effective maneuver to avoid these conditions during bimanual cortex removal and viscoelastic washout. In Khaled technique, rotating the irrigation probe outwards causes complete occlusion of the lumen of the side port and a simultaneous stabilization of the anterior chamber. Twisting the incision by the irrigation probe also offers better fixation of the eye at the edge of the side port and a subsequent reduction of eye movement.