Objective and subjective outcomes of strabismus surgery in Graves' orbitopathy: a prospective multicentre study.

Purpose: To assess the change and interrelationship of the field of binocular single vision (BSV) and the quality of life (QoL), tested with two different tools, after one or two strabismus surgeries in patients with Graves' orbitopathy (GO).

Methods: Prospectively, consecutive patients with GO who were scheduled for their first strabismus surgery were recruited from five centres specialized in the treatment of GO. One week preoperatively and 3 months after the last operation, a full ophthalmic and orthoptic examination was performed. Change in field of BSV, GO-QoL and thyroid eye disease-QoL (TED-QoL) was recorded.

Results: A total of 59 met all the eligibility criteria of whom 15 underwent two strabismus operations. The median (interquartile range) preoperative score of the field of BSV was 0 (0-0), which improved to 73 (53-85) after the correction(s) (p < 0.001). After the first surgery, a significant higher score of the field of BSV was found in the patients who underwent one operation (76; 60-86) compared with those who underwent two 0 (0-63) operations (p < 0.001). After the second surgery, this score increased to 62 (40-76; p = 0.05). A moderate correlation was found between the score of the field of BSV and the GO-QoL visual functioning (VF) questionnaires (r = 0.485; p < 0.001). Both the GO-QoL and TED-QoL for VF and appearance (AP) showed significantly higher scores after the treatment (p < 0.001).

Conclusion: After strabismus surgery in GO patients, both the field of BSV and quality of life questionnaires increase. In approximately 30% of the patients, an additional strabismus surgery is performed. This second surgery significantly expands the field of BSV and the quality of life.