Strabismus surgery among aged medicare beneficiaries

OBJECTIVES: The purpose of this study was to investigate the incidence of strabismus surgery among aged patients in the United States. METHODS: The Medicare Part B claims experience (physician professional fee billing) for 1995 was reviewed for the number of times each strabismus surgical procedure recognized in Physicians' Current Procedural Terminology (CPT) was performed. To determine the indications for the procedures that were performed, a 5% sample of claims was reviewed for the pertinent International Classification of Diseases, Ninth Revision, Clinical Modification, diagnostic codes. RESULTS: There were 27 million aged Medicare beneficiaries eligible for Part B benefits in 1995 in a fee-for-service setting. During that year physicians reported 9497 strabismus physician services. These represented 6585 separate procedures (CPT codes 67311 to 67343) and 277 botulinum toxin (Botox) injections for strabismus (CPT 67345) performed during 1995. Sixty-nine percent of the surgical procedures were for horizontal correction and 28% were for vertical correction. Adjustable sutures were used for only 1240 cases (1 9%). The add-on procedural code for reoperation surgery or surgery in the presence of restriction of the extraocular muscles was used in just 930 cases (14%). The most common diagnosis for horizontal surgery was exotropia. Paralytic strabismus and thyroid disease were identified for 17% of cases. Three percent of the diagnoses were inappropriate for the procedures performed and may have been reported in error. CONCLUSIONS: These data confirm a very low incidence of strabismus surgical procedures (2/10,000) and injections (1/100,000) among aged Medicare beneficiaries. The strabismus surgery was most often performed to repair a horizontal deviation. The adjustable suture technique was used infrequently. These data may be extrapolated into the future to aid in determining the strabismus services that will be needed early in the next century.