Abstract
Purpose
To compare the changes in corneal topography between 23 gauge (G) pars plana vitrectomy (PPV) and 20 G PPV.
Methods
Forty-three eyes of 42 patients who underwent PPV were divided into 2 groups: 20G PPV (Group I, n=18) and 23 G PPV (Group II, n=25). Both groups were followed up over 3 months postoperatively. ORBSCAN II was performed to compare the corneal topographic change of 20 G PPV and 23 G PPV.
Results
In a 5 mm zone, significant postoperative change in the mean corneal surface cylinder was found between the 1st day and the 1st month in Group I, while no significant change was found in Group II. Postoperatively, the increase in the mean corneal surface cylinder in Group I was significantly higher than in Group II between the 1st day and the 1st month. Clinically significant astigmatism, induced by surgery, was found only in Group I one week after the operation. In a 3 mm zone, there was no significant change in the mean corneal surface cylinder in both groups postoperatively. The difference in the mean corneal surface cylinder between the 2 groups at the postoperative periods showed no significant change. Surgically induced astigmatism was significantly higher in Group I than in Group II between the 1st day and the 1st month postoperatively.
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Table 1.
No. of eyes | ||
---|---|---|
Group I | Group II | |
PPV* | 0 | 14 |
PPV+Silicone oil injection | 2 | 2 |
PPV+Gas (C3 F8 or SF6) injection | 5 | 9 |
Silicone oil removal | 11 | 0 |
Total | 18 | 25 |
Table 2.
Preoperative (D*) | Postoperative (D) | |||||
---|---|---|---|---|---|---|
1 day | 1 week | 1 month | 3 months | 6 months | ||
Group I | 43.10±3.25 | 43.57±2.60 | 43.55±3.03 | 43.17±2.09 | 43.53±1.91 | 43.33±2.60 |
Group II | 42.92±1.56 | 42.95±1.27 | 42.95±1.19 | 42.79±1.40 | 42.62±1.80 | 42.54±1.43 |
p value | > 0.05 | > 0.05 | > 0.05 | > 0.05 | > 0.05 | > 0.05 |
Table 3.
Table 4.
Surgically induced astigmatism (D*) | |||||
---|---|---|---|---|---|
1 day | 1 week | 1 month | 3 months | 6 months | |
Group I | 1.56±1.58 | 1.48±1.73 | 1.30±1.07 | 0.33±1.07 | 0.45±2.41 |
Group II | 1.25±1.16 | 0.02±1.38 | 0.29±1.45 | 0.00±0.79 | 0.21±0.89 |
p value | < 0.05 | < 0.05 | < 0.05 | > 0.05 | > 0.05 |