Abstract
Purpose :
We sought to determine whether preoperative anterior segment parameters could predict postoperative day 1 intraocular pressure (IOP) after cataract surgery (CS) in glaucoma patients.
Methods :
We used the Lenstar LS 900 Optical Biometer (Haag-Streit, Koeniz, Switzerland) to preoperatively measure axial length (AL), anterior chamber depth [(ACD), i.e. the distance between the posterior surface of the cornea and the anterior surface of the lens], crystalline lens thickness [(LT), i.e. the distance along the optical axis between the two surfaces of the lens], and white-to-white distance [(WTW), i.e. horizontal iris width] in glaucoma eyes scheduled for CS.
We used generalized estimating equations regression to determine the association of these parameters with IOP change from baseline on day 1 after CS, and to derive the odd ratios (OR) for the occurrence of an acute intraocular pressure elevation (IOP spike). We defined a “5 mmHg IOP spike” as a postoperative day 1 IOP ≥ 21 mmHg that was also ≥ 5 mmHg greater than preoperative IOP, and a “10 mmHg IOP spike” when the elevation was ≥ 10 mmHg. All calculations were adjusted for the number of preoperative ocular hypotensive agents.
Results :
Table 1 shows baseline characteristics of the eyes included.
The IOP on day 1 (22.2 mmHg, SD 8.4, range 11-54) was significantly higher than preoperatively (16.9 mmHg, 4.69, 7-31; p=.004). We found that 38.1% (16/42) of the eyes had a 5 mmHg IOP spike, and 14.3% (6/42) had a 10 mmHg IOP spike.
Patients with shallower ACD had a significantly higher increase in IOP on day 1 (0.64 mmHg per 0.1mm decrease in ACD, p=.023) (Fig. 1, top), and a higher risk of 10 mmHg IOP spike (OR 1.22, p=.013). Similarly, patients with thicker lens had a higher increase in IOP on day 1 (0.91 mmHg higher per 0.1mm increase in LT, p=.005) (Fig. 1, bottom), and were more likely to have a 5 mmHg IOP spike (OR 1.04, p<.001) or a 10 mmHg IOP spike (OR 1.19, p=.053). Patients with shorter AL were slightly more likely to suffer a 10 mmHg IOP spike (OR 1.04, p=.046). Bivariable models showed that AL and LT were significant predictors of a 5 mmHg IOP spike (p<.001 and p=.009, respectively).
Conclusions :
Shallower ACD, shorter AL, and thicker LT were associated with increased risk of IOP spikes on postoperative day 1 in glaucoma patients. This is in contrast to these same parameters being associated with a long-term decrease in postoperative IOP.
This is a 2021 ARVO Annual Meeting abstract.