Accuracy of Corneal Thickness Measurement with Ultrasound Pachymeter in Thin Corneas.
- Author:
Jun Heon KIM
1
;
Jong Suk SONG
;
Hyo Myung KIM
;
Hai Ryun JUNG
Author Information
1. Department of Ophthalmology, Korea University College of Medicine, Seoul, Korea. hyomkim@ns.kumc.or.kr
- Publication Type:Original Article
- Keywords:
Residual stromal bed thickness;
Thin cornea;
Ultrasound pachymeter
- MeSH:
Cornea*;
Corneal Pachymetry*;
Dilatation, Pathologic;
Keratomileusis, Laser In Situ;
Rabbits;
Refractive Surgical Procedures;
Ultrasonography*
- From:Journal of the Korean Ophthalmological Society
2004;45(7):1168-1173
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: Accurate assessment of corneal thickness is important in order to prevent iatrogenic corneal ectasia after laser in situ keratomileusis (LASIK). More accurate measurement is needed in LASIK enhancement because the cornea becomes thin after previous refractive surgery. We evaluated the reliability of corneal thickness measurement with ultrasound pachymeter (USP) in the thin corneas. METHODS: The corneal thickness was measured in the 22 eyes of 11 rabbits. The corneal flap was made with an Automated Corneal Shaper microkeratome (Bausch and Lomb, USA) with 130 micro meter plate and the flap was removed in order to make the cornea thin. Residual stromal bed (RSB) thickness was measured with USP and thickness gauge, and the two measurements were compared. RESULTS: Mean corneal thickness was 404.69 +/- 11.01 micro meter with USP and 133.23 +/- 15.66 micro meter with thickness gauge. RSB thickness measured with thickness gauge was 269.05 +/- 24.19 micro meter and this was not significantly different from the expected RSB thickness, although RSB thickness measured with USP was 388.14 +/- 10.17 micro meter, which was significantly different from the expected RSB thickness (p=0.00). CONCLUSIONS: In the thin corneas, corneal thickness measurement with ultrasound pachymeter is not reliable.
