Abstract
Purpose::
To evaluate long-term intraocular pressure control after clear corneal phacoemulsification in patients with primary open angle glaucoma, ocular hypertension, glaucoma suspects and normal eyes.
Methods::
A retrospective chart review of 426 charts of patients who had uncomplicated clear corneal phacoemulsification, by a single surgeon, between the years of 2000 and 2002 was conducted. Of these patients, those with primary open angle glaucoma (POAG), ocular hypertension (OHT), glaucoma suspects (GS) and normal eyes (N) were identified. This revealed 151 patients (226 eyes) who had an average of least 4 years of follow up. Patients who had secondary glaucoma (i.e. pigment dispersion, pseudoexfoliation, angle recession), previous ocular trauma or surgery were excluded. Kaplan-Meier analysis and two-tailed paired student t tests were applied to evaluate trends in pre- and post-operative IOP and medication usage.
Results::
Thirty-one patients (45 eyes) in the POAG group, thirty-one patients (51 eyes) in the OHT group, twenty-seven patients (42 eyes) in the GS group and sixty-two (88 eyes) in the N group met criteria.Intraocular pressure in all groups was significantly decreased 1 year after surgery. This was maintained at 4 years: -3.7 ±; 3.1 mm Hg (P < 0.0001) in POAG, -2.8 ±; 2.9 mm Hg (P < 0.0001) in OHT, -2.7 ±; 2.6 mm Hg (P < 0.0001) in GS and -2.5 ±; 2.5 mm Hg (P < 0.0001) in N.Intraocular pressure at 4 years versus 1 year after surgery was not significantly different in the POAG, GS or N groups: +0.3 ±; 2.8 mm Hg (P= 0.52) , +0.5 ±; 1.9 mm Hg (P= 0.15) and -0.7 ±; 2.3 mm Hg (P= 0.26) respectively. There was a significant increase in intraocular pressure between year 1 and 4 in the OHT group: +1.3 ±; 2.5 mm Hg (P= 0.00055).Although the number of medications needed for intraocular pressure control significantly decreased 6 months postoperatively in the POAG group, -0.27 ±; 0.66 (P= 0.0089), this difference did not persist 4 years after surgery, +0.10 ±; 0.74 (P=0.40).Survival analysis revealed that 82% of POAG, 83% of OHT, 88% of GS and 89% of N eyes maintained an IOP at or below preoperative levels with the same or less number of glaucoma medications at 1 year. The percentages were 78%, 78%, 84% and 88% respectively at year 4.
Conclusions::
Patients in all groups had a significantly decreased IOP after clear corneal phacoemulsification that is maintained 4 years postoperatively. Although the majority of POAG eyes maintained an IOP below preoperative levels, there was no significant long-term decrease in the number of glaucoma medications used.
Keywords: intraocular pressure • cataract