Quantitative Evaluation Of Berger Space Expansion: Oct-Based Volume Analysis Following Repeated Hydroseparation In Femtosecond Laser-Assisted Cataract Surgery

Primary posterior capsulotomy (PPLC) in femtosecond laser assisted cataract surgery (FLACS), is effective in preventing posterior capsule opacification (PCO), provided that Berger’s Space (BS) is adequately visualized. Transzonular capsulo-hyaloidal hydroseparation facilitates this visualization by detaching the anterior hyaloid membrane (AHM) from the posterior capsule (PC). In this study, we extend our previous qualitative evaluation by incorporating quantitative volumetric analysis using intraoperative OCT imaging, comparing BS volumes at three stages: native (immediately after FLACS), after hydroseparation with balanced salt solution (BSS), and following an additional hydroseparation enhanced with triamcinolone.

In this prospective study, 180 eyes of 96 patients with age-related cataract undergoing FLACS at the Medical University of Vienna were evaluated.

Berger Space was assessed intraoperatively using the integrated OCT of the femtosecond laser (LDV-Z8) and classified into three categories:

Category A: Complete AHM attachment to the PC

Category B: Partial attachment

Category C: No attachment

Measurements were performed at three distinct stages:

Native (Immediately after FLACS): Baseline OCT imaging before any hydroseparation

BSS Hydroseparation: After initial hydroseparation using balanced salt solution

Triamcinolone-Enhanced Hydroseparation: After a second hydroseparation using triamcinolone

In addition to categorical assessment, volumetric measurements of BS were analyzed. 

Native (Immediately after FLACS):

Qualitative: 45% showed detachment, with 40% complete (= Category C).

Quantitative: Mean BS volume = 0.15 ± 0.04 mm³.

After BSS Hydroseparation:

Qualitative: Detachment increased to 58%, with 59% complete.

Quantitative: Mean BS volume = 0.28 ± 0.06 mm³ (p < 0.01 vs. native).

After Triamcinolone-Enhanced Hydroseparation:

Qualitative: Complete detachment rose to 67%, overall to 64%.

Quantitative: BS volume = 0.42 ± 0.08 mm³ (p < 0.01 vs. native and BSS), a 1.87-fold increase post-BSS and 2.8-fold post-triamcinolone versus native.

Repeated hydroseparation leads to a significant expansion of Berger’s Space. The combination of this technique with triamcinolone not only further increases the BS volume but also enhances intraoperative visualization, thereby facilitating a more effective PPLC. This combined approach represents a valuable advancement in optimizing cataract surgery outcomes.