Technique of area measurement of epithelial defects.
OBJECTIVE
To compare two commonly used methods of area measurement of corneal epithelial defects, namely, estimation of the area of an equivalent rectangle and use of image analysis software, the gold standard.


METHODS
Thirty-eight patients with corneal epithelial defects were evaluated. The largest linear dimension of the epithelial defect and its largest possible perpendicular within the confines of the epithelial defect were measured using a slit lamp. The area was then measured using digital photographs and image analysis software. A paired sample t test was used to compare the results.


RESULTS
The two measurements of area correlated well (P = 0.84); their difference was insignificant (P = 0.063) and a linear regression relation between the two could be derived with an r2 value of 0.71, which was significant.


CONCLUSIONS
Accurate slit-lamp measurements with estimation of the area of an equivalent rectangle can safely be used as a measure of the epithelial defect size when sophisticated image analysis software is not available.
Mukerji
Nitin
N
Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.
Vajpayee
Rasik B
RB
Sharma
Namrata
N
D000328:Adult; D003316:Corneal Diseases / Q000473:pathology*; D003936:Diagnosis, Computer-Assisted; D003941:Diagnostic Techniques, Ophthalmological / Q000592:standards; D019573:Epithelium, Corneal / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D010781:Photography