Eyebrow tissue expansion: an underappreciated entity in thyroid-associated orbitopathy.

Objectives: To report photographic evidence of eyebrow tissue expansion in patients with thyroid-associated orbitopathy (TAO) and to demonstrate consistency in grading through the use of standardized photographs.

Methods: A retrospective cohort study of patients referred for evaluation of TAO in an orbitofacial tertiary care center between January 1, 2000, and December 31, 2010. A grading key was produced with representative views of each of 4 grades (0 [no expansion] to 3 [severe expansion]), corresponding to increasing severity of eyebrow tissue expansion. Photographs of each study patient, including both premorbid and morbid photographs, were retrieved from an electronic medical record system and graded by 6 independent, masked observers using this 4-point system.

Results: Seventy-five patients with TAO were identified for inclusion. The average grade was 0.3 for premorbid eyes and 1.1 for morbid eyes. Intraclass correlation coefficients for the premorbid photographs were 0.705 and 0.632 for the right and left eyes, respectively. Intraclass correlation coefficients for the morbid photographs were 0.921 and 0.916 for the right and left eyes, respectively.

Conclusions: Eyebrow tissue expansion is a common manifestation in TAO. Comparison of premorbid and morbid photographs is a useful means to identify and characterize the extent of brow involvement. The use of a grading key improves the consistency of identifying and grading eyebrow tissue expansion. Recognition of the eyebrow tissue as distinct anatomically in TAO may be crucial to rehabilitation of these patients, which may entail multiple surgical procedures.