RESUMO
PRCIS: Femtosecond laser-assisted cataract surgery leads to an increase in intraocular pressure (IOP) during the procedure and subsequent IOP reduction after surgery, with greater magnitude in eyes with higher preoperative IOP. PURPOSE: To evaluate the effect of femtosecond laser-assisted cataract surgery (FLACS) using the LDVZ8 laser on intraocular pressure (IOP) during and after surgery, and to compare the IOP-lowering effect of FLACS and conventional phacoemulsification cataract surgery (CPCS). PATIENTS AND METHODS: This prospective cohort study enrolled 395 healthy eyes (395 patients) scheduled for FLACS (n=245) and CPCS (n=150). FLACS was performed using the LDVZ8 laser. During FLACS, IOP was assessed before and immediately after docking. IOP reduction during a six-month postoperative period was evaluated following FLACS and CPCS. Multivariate analyses were performed. RESULTS: Mean IOP increase after docking was 2.3±4.1 mmHg (P<0.0001); maximum increase 17.6 mmHg, peak 38 mmHg. Sixty-one (61) eyes (25.1%) demonstrated an increase of ≥5 mmHg and 10 (3.7%) showed an increase of ≥10 mmHg; pre-docking IOP was associated with an IOP increase of ≥5 mmHg (P-0.029). IOP reduction over six months post-surgery was similar for FLACS and CPCS (P>0.05),-1.33±3.12 mmHg for FLACS (P<0.001) and -1.4±2.87 mmHg for CPCS (P<0.001). Preoperative IOP correlated statistically significantly with IOP reduction in both FLACS (ß -0.742, P<0.001) and CPCS (ß -0.743, P<0.001). CONCLUSIONS: Although the LDVZ8 laser procedure causes an increase in IOP in some healthy eyes, a subsequent decrease in IOP is observed after FLACS. The IOP-lowering effect of FLACS is similar to CPCS, and tends to be more pronounced in eyes with higher preoperative IOP. Eyes with higher preoperative IOP are prone to IOP elevation during FLACS, a critical consideration for glaucoma patients.
RESUMO
PRCIS: Femtosecond laser-assisted cataract surgery (FLACS) may cause thinning of the peripapillary retinal nerve fiber layer (pRNFL) in healthy eyes. PURPOSE: This prospective cohort study aimed to compare changes of pRNFL after FLACS using a liquid patient interface and conventional phacoemulsification cataract surgery (CPCS). PATIENTS AND METHODS: Included were 261 eyes (261 patients) with age-related cataracts and no ocular diseases scheduled either for FLACS (222 eyes) or CPCS (39 eyes). FLACS was performed using a Ziemer LDV Z8 laser. Average and quadrant pRNFL thickness was measured using optical coherence tomography before surgery and at 1, 3, and 6 months postoperatively. Postoperative changes in pRNFL thickness were compared within and between groups. RESULTS: Mean quadrant and average pRNFL thicknesses significantly increased after both surgeries (P<0.001). However, pRNFL thinning occurred after FLACS and CPCS (17% vs. 5.1%, respectively, P>0.05). FLACS eyes showed a significant and stable decrease of average pRNFL thickness (P=0.057) and a gradual decrease in pRNFL thickness of all quadrants (P≤0.018). CPCS eyes showed an initial increase of pRNFL thickness, followed by a decrease only in the nasal quadrant and average pRNFL. Preoperative pRNFL thickness was associated with thinning of the temporal quadrant (P=0.04). CONCLUSIONS: Both FLACS and CPCS demonstrated pRNFL thinning in some healthy eyes. Although the higher rate of pRNFL thinning after FLACS compared with CPCS lacked statistical significance, a consistent decrease in pRNFL thickness occurred in all quadrants and average pRNFL of FLACS eyes, suggesting that FLACS may lead to pRNFL thinning. Eyes with thinner preoperative pRNFL may be prone to temporal quadrant thinning after FLACS.