Prevalence of Preoperative Corneal Astigmatism in Patients Undergoing Cataract Surgery at Mettapracharak Hospital, Thailand
Nauljira Prakairungthong MD*, Puwat Charukamnoetkanok MD*, Saichin Isipradit MD*
Affiliation : * Mettapracharak Eye Center, Mettapracharak (Wat Raikhing) Hospital, Nakhon Pathom, Thailand
Objective : To describe and analyze the demography and distribution of preoperative corneal astigmatism in patients
undergoing cataract surgery at Mettapracharak Hospital.
Material and Method: The medical records of consecutive patients who had cataract surgery between October 1, 2010 and
September 30, 2011 at Mettapracharak Hospital were retrospectively reviewed and analyzed. Patient demographic and
keratometric data were collected and analyzed.
Results : The present study evaluated the keratometric data in 2,688 eyes of 2,671 patients who had cataract surgery with
the mean age of 66.2310.79 years. The mean corneal astigmatism was 1.09 D (range 0.00-8.50 D). Corneal astigmatism
was higher than 1.00 D in 36.6%, between 0.51 D and 1.00 D in 37.9% and 0.50 D or less in 25.5% of eyes. The mean steep
keratometry and flat keratometry values were 44.891.52 D and 43.811.57 D respectively. The magnitude of corneal
astigmatism was positively correlated with age (p<0.001) and there was a tendency for corneal astigmatism to increase
with age above 50 years. Female had significantly steeper corneas than male. Corneal astigmatism was mainly against-
the-rule (the steepest meridian at 18030 degrees). The type of corneal astigmatism was strongly correlated with age.
Against-the-rule astigmatism increased with older age. While aging decreased with-the-rule astigmatism.
Conclusion : The present report showed the pattern of corneal astigmatism before cataract surgery in Thai governmental
hospital, approximately one third of cataract patients had more than 1.00 D of astigmatism. This finding provide the important
normative reference and help ophthalmologists to plan and manage the cost-effective correction of preexisting corneal
astigmatism in cataract patients to achieve the best visual outcome.
Keywords : Preoperative corneal astigmatism, Cataract surgery
