Abstract:
Purpose: Analysis of the qualitative changes in the posterior eye segment structures – choroid
thickness (CT) and distance height of vitreous posterior hyaloid membrane (VPHM) from retina by
spectral optical coherence tomography (SOCT) method in femtosecond laser–assisted cataract
surgery (FLACS).
Methods and Materials: 46 eyes with immature cataract and retinal SOCT possibility before the
operation. Average corrected visual acuity – 0.3±0.05; eye length - 22.51±0.9 mm; IOP – 20 mm
Hg; age - 65 years. Before and after surgery (1, 3, 5 days), SOCT of vitreoretinal interface and
choroid was performed, RTVue XR 100 «Avanti», Optovue. Group 1, 24 patients, ultrasound FEM
of cataract, «Stellaris», B&L. Group 2, 22 patients – FLACS, LenSx, Alcon. Capsulorhexix
diameter – 4.9-5.2 mm (energy 12.5 μJ). Fragmentation of the lens nucleus by «chop», «cylinder»
methods (energy 10-15 μJ). The main corneal incision – 2.5 mm (energy 5 μJ). Phakoaspiration on
«Stellaris», elastic IOLs were implanted. FLACS duration – 9-10 minutes, femtolaser effect ≤
2 minutes.
Results: Before the surgery CT in Group 1 was 253.1±62.1 microns. In 1, 3, 5 days after FEM of
cataract CT were 310.4, 262.7, 258.1 microns. Distance height of VPHM before the surgery was
400.1 microns. In 1, 3, 5 days after surgery – 505.6, 492.7, 500.3 microns.
In Group 2 before the surgery CT was 256.4±60.3 microns. In 1, 3, 5 days after FLACS CT were
333.1, 279.4, 259.1 microns. Distance height of VPHM before the surgery – 366.2 microns. In 1, 3,
5 days after FLACS – 510.8, 506.2, 508.9 microns.
Reactive thickening of the choroid after surgery was determined in both groups. Group 1, 1th day –
57.3 microns (22.6%). By the 5th day CT became initial. Distance height of VPHM increased by
105.5microns. By the 5th day the situation was not changed. Group 2, FLACS, thickening of CT
per 1 day is 76.7 microns, (29.9%). By the 5th day CT returned to previous values. VPHM was
increased by 144.6 microns. By the 5th day the situation was not changed.
Conclusion: Increase of TC and distance height of VPHM in the early postoperative period was
noticed in the both groups. After FLACS big figures are conditioned apparently by intraoperative
vacuum effect and/or sudden IOP changes during femtolaser stage. Return of CT to initial state
indicates processes reversibility. Patients with vitreomacular adhesion when FLEC are highly risky
of vitreomacular traction.
