Ultrasonically measured horizontal eye muscle thickness in XXXX : cross-sectional and longitudinal aspects in a Danish series.

@entity1 @entity227 @entity229 @entity205 @entity1374
PURPOSE: To analyse horizontal extraocular muscle findings by ultrasound and exophthalmometry in a tertiary endocrinology centre series of @entity1 with @entity1374 ( @entity1374 ). METHODS: The 90 thyroid @entity1 included underwent ultrasonic measurement of horizontal eye muscle thickness by a B-scan based technique carried out in addition to their general ophthalmic evaluation. As an indicator of mainly advanced @entity1374 , longterm @entity229 or @entity205 was given to many of the @entity1 , and drug-resistant @entity227 indicated decompression surgery in four of the 90 @entity1 . Thirty-four @entity1 underwent repeated muscle recordings over 15-49 months; this allowed for cross-sectional analysis and the outlining of longitudinal trends. RESULTS AND CONCLUSIONS: (A) Although marginally overlapping, all four muscle groups were significantly thicker in the study group than in normal control subjects. The mean of the sum of all four muscles was 16.8 mm (range 13.6-21.7 mm) in the control group versus 22.6 mm (range 15.5-36.4 mm) in the thyroid group. (B) Using the clinical NOSPECS grading, more advanced eye involvement was found to generally result in a higher exophthalmometric measurement of protrusion and eye muscle thickness. However, slender rectus muscles and/or normal exophthalmometric values might occur even in advanced orbitopathy. (C) Over a period of 2-4 years, only a few of 34 @entity1 with satisfactory serial ultrasonic measurements returned to their premorbid ophthalmic status. Typically, the extraocular muscles kept their abnormal size after having become clinically quiescent (fibrotic). (D) We found no safe indication regarding disease stage, active or late, from the ultrasonic appearance of the muscle tissue. (E) Discrepancies between various normative eye muscle studies are discussed with regard to computer tomography and magnetic resonance imaging.
