Abstract
Purpose :
To determine postoperative one-hour intraocular pressure spikes (IOP) in patients
undergoing MLT or SLT, and to compare the long-term efficacy of two modalities.
Methods :
A retrospective chart review of patients diagnosed with glaucoma or increased
intraocular pressure at Cook County Health Hospital Systems was performed. Demographic
information, medications, co-morbidities, laser settings, and intraocular pressures were
recorded. IOP spikes were defined per the American Academy of Ophthalmology as pressures
>5mm from baseline.
Results :
A total of 37 eyes were analyzed, 15 undergoing SLT and 22 undergoing MLT. Of the
15 patients undergoing SLT, 1 patient had a post-operative 1 hour IOP spike of 5mm (23%
increase), 5 patients had no IOP changes, and 9 patients had decreased IOP. 2 out of 15 patients (14%) had to increase the number of IOP lowering drops within 6 months of SLT while 13 patients(86%) remained on the same number of drops. The average number of drops was 2.2
preoperatively, 2.6 at 6 months postoperatively, and 2.8 at 1 year postoperatively.
Of the 22 patients undergoing MLT, 0 patients had a post-operative 1 hour IOP spike, 17
patients had no IOP changes, and 5 patients had decreased IOP. All 22 patients (100%)
remained on the same number of IOP lowering drops within 6 months of MLT while 2 required additional IOP lowering drops by 1 year postoperatively. The average number of drops was 1.5 preoperatively, 1.5 at 6 months postoperatively, and 1.9 at 1 year postoperatively.
Of the 22 MLT verses 15 SLT treated patients, there were 0 vs 1 pressure spikes at 1 hour and 0 vs 2 pressure spikes at 1 week post-operatively respectively (p<0.05). There was no significant difference in IOP change from baseline between the two modalities at 1 month (p=0.07), 3 months (p=0.40), 6 months (p=0.20), 9 months (p=0.48), 12 months (p=0.20), or18 months (P=0.08).
The rate of additional surgical intervention at 1 year was similar between the groups (SLT 20%, MLT 18%).
Conclusions :
Intraocular pressure spikes at 1 hour and 1 week post operatively were only seen in SLT treated patients. Long term pressure changes were similar amongst the 2 modalities showing similar long term efficacy. Further study is needed to determine the association between MLT and acute pressure changes postoperatively.
This is a 2020 ARVO Annual Meeting abstract.