Abstract
Purpose:
The optical density of the cornea could be quantitatively evaluated as “densitometry” by a Scheimplug rotating camera, Pentacam®. Previous investigations showed that densitometry was useful to quantify stromal opacity aflter excimer laser refractive keratectomy and from mucopolysaccharideosis, or healing processes of the infectious corneal ulcers. In addition, the densitmetry was also used as an indicator for corneal epithelial edema due to bullous keratopathy. In the present investigation, we tried to detect subclinical corneal edema shortly after uneventful cataract surgery.
Methods:
Twenty-seven eyes of 17 patients (age 71 +/- 8.4 years-old, 8 females and 9 males), who underwent cataract surgery at Deparment of Ophthalmology, National Defense Medical College between April 2013 and October 2013, were enrolled. Eight eyes revealed posterior subcapsular type cataract, and 17 eyes revealed cortical opacity. Two revealed mature cataract. The eyes that showed dry eye or superficial punctate keratopathy preoperatively were excluded. Cataract surgery was performed by phacoemulsification and aspiration through small incision (2.4mm). Measurement of corneal density was performed using the scheimplug rotating camera, Pentacam® system before, and 1, 3, and 7 days after the surgery. Densitometry readings at corneal center between 0 to 120 µm in depth was recorded, and JMP software version 9 was used for statistical analysis.
Results:
Densitometry score that was 18.15 +/- 1.78 before cataract surgery, increased to 20.89 +/- 3.88 at 1 day (p = 0.0003) and 19.78 +/- 2.42 at 3 days (p = 0.02), but decreased to 19.71 +/- 2.15 at 7 days (p = 0.05) after the surgery. Total corneal thickness at the corneal apex that was 547.1 +/- 32.3 µm preoperatively increased to 588.8 +/- 55.1 µm at the next day of surgery (p=0.0002), however, recovered to 563.4 +/- 32.5 µm at 3 days (p = 0.13) and 565.6 +/- 29.0 µm at 7 days (p = 0.15) after the surgery. Densitometry readings was positively correlated with the corneal thickness (correlation coefficient was -0.10, p = 0.001)
Conclusions:
The present results showed that the densitometry is useful to detect minimum subclinical corneal edema that is usually not identified by slit-lamp examination.
Keywords: 445 cataract •
482 cornea: epithelium