Abstract
Purpose: :
To study long term effect of phacoemulsification on intraocular pressure (IOP), anterior chamber depth, specular count and number of glaucoma medications in glaucoma patients.
Methods: :
Records of one hundred and thirty consecutive patients with glaucoma and visually significant cataract, who had undergone phacoemulsification with intraocular lens implantation in bag, were reviewed. All surgeries had been performed by a single surgeon, and were uncomplicated. Pre-operative and post-operative data (1 year) regarding intra-ocular pressure, anterior chamber depth, specular count and number of medications were noted and values statistically analysed.
Results: :
The mean pre-operative IOP were 15.02+/-2.8 mm Hg , 16.8+/-2.5 mm Hg, 12.58+/-3.14 mmHg, in Primary Angle Closure Glaucoma (PACG) (n=67), Primary Open Angle Glaucoma (POAG) (n=24) and operated trabeculectomy patients (n=39) respectively (p=0.001). Mean postoperative IOP were 14.47+/-2.6 mm Hg, 16.4+/-2.45 mm Hg and 12.98+/-3.2 mm Hg, in same order (p=0.02). The percentage change in IOP was not significantly different between the PACG and POAG eyes, with a 2.4% (mean 0.55+/- 2.74 mm Hg), decrease in IOP in the PACG group and 1.76 % (mean 0.4+/- 2.49 mm Hg), fall in the POAG group (p= 0.76). The operated trabeculectomy patients showed a 3.17 % (mean 0.4+/- 3.16mm Hg), rise in post-operative IOP, which was statistically significant when compared to PACG (p =0.023) and POAG eyes, (p=0.03). The number of eyes showing a change of ≥ 2 mm Hg pressure in postoperative IOP measurements was 24 out of 67 (35.8%) of PACG eyes , 17 out of 24 (70.8%) of POAG eyes, and 8 out of 39 (20.5%) of operated trabeculectomy eyes (p = 0.04). Specular counts showed a decline in all three categories by 7.6%, 6.13% and 7.2% respectively (p=0.755). Percentage increase in anterior chamber depth in the 3 categories was 51.7%, 29.3% and 60.4%, (p=.002), and highest in operated trabeculectomy eyes. There was no significant change in the number of anti-glaucoma medications before and after surgery amongst the 3 categories.
Conclusions: :
: Phacoemulsification does not result in a clinically significant fall in IOP in POAG, PACG or operated glaucoma eyes in the long term, but leads to a significant loss of endothelial cells. Therefore phacoemulsification should be undertaken only for clinically significant cataracts, not for control of IOP.
Keywords: intraocular pressure • intraocular lens • cornea: endothelium