J Korean Ophthalmol Soc.  2009 Mar;50(3):353-358. 10.3341/jkos.2009.50.3.353.

Comparisons of Corneal Topographic Change Between 20-Gauge and 23-Gauge Pars Plana Vitrectomy

• Park YM
• Lee JE
• Oum BS

• KMID: 2111244
• DOI: http://doi.org/10.3341/jkos.2009.50.3.353

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.
CONCLUSIONS
PPV with the 23 G system is a sutureless transconjunctival surgery, which appears to be more effective due to insignificant corneal surface and astigmatic changes in the early postoperative period.

Keyword

Corneal topography; Vector analysis; 23 G Vitrectomy

MeSH Terms

Astigmatism
Corneal Topography
Eye
Humans
Postoperative Period
Vitrectomy

Figure

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  Figure 1. Changes in mean astigmatism (in 5-mm zone) after 20-gauge and 23-gauge pars plana vitrectomy.* Statistically significant change between preoperative and each postoperative periods; † Statistically significant change between Group I and Group II at each time interval.

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  Figure 2. Changes in mean astigmatism (in 3-mm zone) after 20-gauge and 23-gauge pars plana vitrectomy. Significant changes of mean astigmatism were not found in both groups postoperatively.

Reference

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