Study shows use of new index accurately diagnoses keratoconus
NEW ORLEANS — Bowman’s ectasia index showed a highly significant correlation to keratometric astigmatism in a study of 40 patients, a speaker reported here.
“Bowman’s layer inferior thinning index has a very high predictive accuracy for the diagnosis of keratoconus,” Mohamed Abou Shousha, MD, PhD, FRCS, said at Refractive Surgery Subspecialty Day preceding the American Academy of Ophthalmology meeting. “But can we improve the sensitivity and specificity of Bowman’s layer index?”
Mohamed Abou Shousha
Shousha and colleagues looked at 20 patients with keratoconus and 20 controls, comparing the inferior thinnest point of Bowman’s layer to the patient’s own normal Bowman’s layer thickness.
He said the Bowman’s ectasia index (BEI) is computed as Bowman’s minimum inferior thickness divided by average thickness of the superior Bowman’s layer, multiplied by 100.
“We found it is very descriptive,” Shousha said.
He said that Bowman’s layer vertical topographic thickness maps of keratoconus patients disclose characteristic localized relative inferior thinning.
“BEI showed accuracy and sensitivity and specificity in the diagnosis of keratoconus,” Shousha said, “and correlates with keratometric astigmatism.”
Disclosure: Shousha has no relevant financial disclosures.