Abstract
Purpose :
Densitometry is the quantitative measurement of optical density. It is known that densitometry readings was increased corneal opacity and corneal edema diseases. Corneal epithelial edema was usually seen by slit lamp examination, but when epithelial edema was slightly, we cannot looked. So we reported that evaluation of slight corneal epithelial edema by using densitometry in cataract surgery, small invasive surgery.
Methods :
Fifty-four eyes of 34 patients (aged 71 ± 8.4 years, 18 males and 16 females) who underwent cataract surgery between April 2013 and October 2013 were enrolled. Dry eye or superficial punctate keratopathy was excluded. Measurement of corneal density was performed using Pentacam® before and on days 1, 3 and 7 after surgery. The cornea is divided into 6 portions according to the zone and the depth; 2 zones in concentric circles from the corneal apex (central 2 mm zone, surrounding 2–6 mm annulus) and 3 depths (anterior layer: from the corneal surface to a depth of 120 µm, center layer: between the anterior and posterior layers, and posterior layer: the deepest 60 µm). The densitometry value is expressed as the average score in each portion.
Results :
Densitometry readings in the central 2 mm zone within the anterior layer was increased from 18.1 ± 1.8 before cataract surgery to 21.0 ± 3.8 on day 1 (P < 0.001) and 19.9 ± 2.5 on day 3 (P = 0.018), but recovered to 19.4 ± 1.6 on day 7. Densitometry readings in the 2–6 mm annulus within the anterior layer was 19.1 ± 4.7 before surgery and increased significantly to 22.2 ± 7.4 on day 1 (P = 0.046) but declined to 20.7 ± 4.6 on day 3. In the center layer, the densitometry readings showed no significant changes both in the central 2 mm zone and the 2–6 mm annulus throughout the study period. In the posterior layer, densitometry readings in the central 2 mm zone increased significantly only on day 1 (10.8 ± 1.3 to 12.4 ± 2.9, P = 0.003), but returned to preoperative value on day 3. Total corneal thickness was 549.1 ± 32.7 µm before surgery and increased to 582.7 ± 46.3 µm on day 1 (P = 0.001), but recovered to 566.4 ± 29.7 µm on day 3. Densitometry reading in the central 2 mm zone for the anterior layer was only correlated positively with corneal thickness (P = 0.003).
Conclusions :
Densitometry is useful to detect corneal edema that is not detectable by slit-lamp examination.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.