Comparison of Ziemer LDV Z8 femtosecond laser pretreatment of cataract and conventional phacoemulsification in primary angle closure disease (PACD).

PURPOSE: Determine if FLACS in PACD is safe and if predicted IOP rise would lead to long-term sequelae.

SETTING

Singapore National Eye Centre.

DESIGN

Prospective randomised control study.

METHODS

Subjects with stable PACD and pre-existing LPIs were randomised to FLACS, or conventional phacoemulsification (control). The former underwent pre-treatment using the Ziemer LDVZ8 docking system. Supine IOP was measured at 4 time-points using an applanation tonometer - prior to speculum insertion, with speculum in-situ, with suction on, and 1 minute after suction off. The control group had IOP measured at the first 2 time points. HVF and OCT RNFL measurements were performed preoperatively, 6- and 12-months post-operatively.

RESULTS

57 eyes successfully treated. In both groups, mean IOP prior to and after speculum placement was similar. In the FLACS group, mean IOP during suction was 78.67mmHg (SD 12.07) and 1 minute post release of suction was 16.92mmHg (SD 3.68). Mean preoperative VF mean deviation (MD) for both groups was similar, -5.07 ± 3.17 SD in the FLACS group and -5.68 ± 4.77 in the control group, with improvement in both at 1 year, to -4.15 ± 5.49 and -2.25 ± 6.08 respectively. In the FLACS group, the average RNFL thickness pre- and post-operatively was 73.2 ± 25.1 SD and 87.9 ± 9.9 SD. In the controls, the average RNFL thickness pre- and post-operatively was 81.9 ± 21.4 SD and 81.5 ± 20.8 SD.

CONCLUSIONS

The transient increase in IOP induced by FLACS did not increase glaucomatous damage in PACD eyes after 1 year.