Clinical evaluation of surgery-induced astigmatism in cataract surgery using 2.2 mm or 1.8 mm clear corneal micro-incisions.
OBJECTIVE
To evaluate corneal astigmatism after phacoemulsification using 2.2 mm or 1.8 mm clear corneal micro-incisions and its effects on visual function.


METHODS
Sixty cases (60 eyes) with cataract were randomly divided into groups A (n=30) and B (n=30) respectively underwent 2.2 mm and 1.8 mm clear corneal tunnel incision phacoemulsification combined with folding intraocular lens implantation from the time direction of 11:00. On day 1 and at 1, 4, and 6wk after operation, patients' vision was measured and both the corneal curvature and corneal thickness (CT) were recorded using Pentacam.


RESULTS
The measured surgery-induced astigmatism (SIA) in both groups A and B peaked on day 1 after operation, and then gradually decreased and eventually stabilized in week 4. No statistically significant difference was found in corneal astigmatism between two groups (P>0.05). The measured corneal astigmatism at 4wk and 6wk postoperatively were 0.28±0.09 D and 0.27±0.10 D for groups A and 0.27±0.09 D and 0.25±0.10 D for groups B without statistically significant difference (P>0.05). In addition, no significant differences in visual acuity and CT were found between groups A and B before or after operation.


CONCLUSIONS
Both 2.2 mm and 1.8 mm micro-incision cataract surgeries result in relatively small SIA with no difference in visual function and corneal astigmatism between two surgery approaches. Thus, the two types of surgical systems are safe and efficient for cataract treatment, by which satisfactory uncorrected visual acuity can be regained early postoperatively.
Cornea & Refractive surgery, Tianjin Medical University Eye Hospital, Tianjin 300384, China.
Jun
J
Yang
Cornea & Refractive surgery, Tianjin Medical University Eye Hospital, Tianjin 300384, China.
Xiu
X
Wang
Cataract Surgery, Tianjin Medical University Eye Hospital, Tianjin 300384, China.
Hong
H
Zhang
Associate Dean for Research, Illinois College of Optometry, 3241 S, Michigan Ave, Chicago, IL 60616, USA.
Yi
Y
Pang
Cornea & Refractive surgery, Tianjin Medical University Eye Hospital, Tianjin 300384, China.
Rui-Hua
RH
Wei
corneal astigmatism; phacoemulsification; surgery-induced astigmatism