Prospective study on exclusive, nonsurgical strontium-/yttrium-90 irradiation of pterygia.

PURPOSE: Prospective study to evaluate consecutive treatment results and to demonstrate safety and efficacy of nonsurgical, exclusive strontium-/yttrium-90 beta-irradiation of nonoperated pterygia.

PATIENTS AND

METHODS

Between November 1999 and March 2002, 20 patients with 21 primary pterygia and six patients with recurrent pterygia after former surgery were treated with exclusive strontium-/yttrium-90 irradiation up to a total dose of 3,600 cGy (six fractions) and 4,800 cGy (eight fractions), respectively. All patients were referred from a single institution. The mean follow-up is 35.6 +/- 7.3 months (range 24-48 months).

RESULTS

Prior to irradiation the mean horizontal diameter of all pterygia was 2.6 mm and shrank to a mean diameter of 1.6 mm after treatment (p = 0.0011, Student's t-test). The treatment led to a reduction in size of all 21 primary and all six recurrent pterygia. Visual acuity reached a value of 0.73 before and 0.82 after treatment. This improvement was not significant in Student's t-test (p = 0.12). The visual acuity did not decrease in any patient, complications were not observed, and in none of the 27 pterygia a recurrence developed

CONCLUSION

Exclusive strontium-/yttrium-90 irradiation of the early and moderately advanced pterygium is a very efficient and very well-tolerated method of treatment. As to the therapeutic management, it is suggested to apply beta-irradiation prior to the development of an astigmatism-relevant pterygium, which requires excision.