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EDTA chelation for calcific band keratopathy: results and long-term follow-up
Dany M Najjar1, Elisabeth J Cohen, Christopher J Rapuano
1Cornea Service, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Purpose:
To determine the etiologies and management of calcific band keratopathy (CBK), and assess the results and long-term follow-up after ethylenediamine-tetraacetic acid (EDTA) chelation.
Design:
Retrospective interventional case series.
Methods:
Two hundred thirty patients with clinically significant CBK were included from January 1996 to July 2002. Among these, 54 patients (65 eyes) underwent EDTA chelation. Outcome measures included symptomatic relief, visual improvement, and recurrences. The improvement or worsening of the number of lines of Snellen best-corrected visual acuity was determined at 1 month and at last follow-up visit.
Results:
The most common causes of CBK were chronic corneal edema in 80 eyes (28%) and idiopathic in 74 eyes (25.9%). The mean follow-up time after EDTA chelation was 36.6 months (range, 1 month to 29.6 years). Forty-four of 45 patients (98%) reported partial or complete symptomatic relief. Seventeen eyes (33.3%) improved 2 or more lines at 1 month and 18 eyes (35.2%) at last follow-up visit (P =.0001). In patients with an initial visual acuity between 20/50 and 20/400, 15 eyes (47%) improved 2 or more lines at 1 month and 16 eyes (50%) at last follow-up visit. Ten of 56 eyes (17.8%) had a recurrence at a mean time of 17.7 years (range, 1 month to 26 years). The highest number of recurrences was in three of five eyes with uveitis (60%; P =.03).
Conclusion:
Chelation with EDTA is an effective treatment of CBK. Visual acuity improves most in eyes with acuity between 20/50 and 20/400. This treatment can be used as the initial surgical intervention after conservative measures fail.
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