The aftermath of orbital radiotherapy for graves’ ophthalmopathy☆
Received 29 October 2001; accepted 3 May 2002.
Abstract
Objective
To determine whether long-term improvement could be observed after orbital radiotherapy for Graves’ disease; in addition, to evaluate ancillary treatments needed for those who have received radiotherapy, to search for late-emerging adverse consequences of radiotherapy, and to relate orbital changes to serum levels of thyroid-stimulating immunoglobulin (TSI).
Design
Three-year follow-up of noncomparative interventional case series.
Participants
Forty-two patients.
Intervention
All patients had received orbital radiotherapy within 6 months of study entry. Twelve months after study entry, patients were free to select any additional treatment for their ophthalmopathy.
Main outcome measures
Need for surgery, steroid therapy, volume of extraocular muscles and fat, proptosis, area of diplopia fields and range of extraocular muscle motion, volume changes after decompression and correlations of eye findings with serum TSI levels, retinal status.
Results
Half of the patients elected to have a surgical procedure on their eyes or orbits. Among patients who were not decompressed, we found only slight improvement in some of the main outcome measures. TSI did not positively correlate with baseline status or with any observed change in major outcome measures. After orbital decompression, the volumes of both muscle and fat increase, but bony orbital volume increases more and proptosis diminishes. Retinal microvascular abnormalities consistent with radiation retinopathy developed de novo in five eyes of three patients within 3 years of radiation therapy.
Conclusions
In this 3-year uncontrolled follow-up phase, limited evidence for a clinically significant improvement was observed, which may be the result of treatment or of natural remission. In either case, the changes are of little clinical significance. Because it is neither effective nor innocuous, radiotherapy does not seem to be indicated for treatment of mild to moderate ophthalmopathy.
Manuscript no. 210911.
1Department of Medicine, Mayo Clinic, Rochester, Minnesota. USA
2Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
3Division of Endocrinology, Mayo Clinic, Rochester, Minnesota, USA
4Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA
5Department of Diagnostic Radiology, Mayo Clinic, Rochester, Minnesota, USA
Reprint requests to Colum Gorman, MB, PhD, Mayo Clinic, Department of Medicine, 200 First Street Southwest, Rochester, MN 55905.
☆ Supported in part by NIH RO1 grant number 188-92, by a General Clinical Research Center grant to Mayo Foundation from the National Institutes of Health (MO1-RR00585) awarded to the Mayo Clinic, Rochester, Minnesota and by Research to Prevent Blindness, Inc., New York, New York.
JD Earle, MD, is now at Mayo Clinic, Jacksonville.
ABSTRACT