An unusually bright, or hyperechoic, deltoid muscle on ultrasound may be a result of insulin resistance and thus a sign of diabetes, according to a new study. In patients without diabetes, the deltoid is typically hypoechoic relative to the underlying supraspinatus tendon, researchers noted in a presentation November 26 at the Radiological Society of North America (RSNA) 2018 Scientific Assembly and Annual Meeting in Chicago.

"These findings may allow us to diagnose diabetes and even prediabetes earlier," Dr. Steven Soliman of the Henry Ford Health System in Detroit told Reuters Health by email.

Dr. Soliman and colleagues reviewed shoulder ultrasounds from 137 patients with type 2 diabetes whose average BMI was 34.7 kg / m2, including 13 patients with prediabetes confirmed by hemoglobin A1c levels and medications.

Three musculoskeletal radiologists reviewed the deltoid images and rated them as normal, suspected diabetes, or defined diabetes. They compared the findings with 49 ultrasounds from obese nondiabetic patients.

Seventy-seven percent of the diabetic patients were classified as " suspected diabetes " or "defined diabetes," and 89% of the "defined diabetes" classifications were accurate.

A hyperechoic deltoid was also a predictor of pre-diabetes, with all pre-diabetics classified as "suspected diabetes" or "defined diabetes," and 77% given to "definite diabetes" designation. 82% of the non-diabetic patients were identified as having "definite diabetes."

"It was important to do this study to confirm that the bright deltoid muscle on the shoulder ultrasound that we have been seeing for years in diabetic patients corresponded with prediabetes and diabetes," Dr. Soliman explained.

"With the increased utilization of shoulder ultrasound, this appearance may be used as an opportunity to diagnose prediabetic and diabetic patients who may otherwise go undiagnosed."

Co-author Dr. Kelli A. Rosen, also at Henry Ford, added, " Radiologists have a new opportunity to catch otherwise undiagnosed prediabetes and type 2 diabetes and positively impact patient outcome."

"This potential to diagnose prediabetes or diabetes in real time via low-cost ultrasound may allow for earlier intervention, treatment, and potentially decreased morbidity," Dr. Rosen told Reuters Health by email.

"This technique may be especially useful in regions where traditional methods for diagnosis or detection are less readily available," Dr. Rosen. Dr. Soliman and his team have unanswered questions to explore.

Methods for diagnosis

"Many of the diabetic patients we see with this bright appearance of the deltoid muscle during shoulder ultrasound are not being medicated for diabetes." Could these findings suggest they should be treated earlier? " I have asked

"Also, could this appearance correspond to functional changes in the muscles or tendons resulting in known problems in diabetics, including being more prone to injury or having difficulty healing?"