Ultrasound of peripheral nerves in acromegaly: Changes at 1-year follow-up

Context We have previously demonstrated peripheral nerve enlargement in acromegaly. Objective The aim of this study was to use ultrasound (US) to assess any changes in the peripheral nerves of patients with acromegaly 1 year after the first evaluation. Patients We prospectively examined the median and ulnar nerve cross-sectional area (CSA) in 34 non-diabetic, patients with acromegaly (18 females and 16 males; 18-79 years) and 34 age-, sex-, BMI-matched controls, using a 17-5 MHz US probe. Intervention The median nerve was examined at the mid-forearm (MN-f) and at the carpal tunnel (MN-Ct) levels; the ulnar nerve at mid-forearm (UN-f) and at distal arm (UN-a). Patients were grouped according to the clinical control of the disease: 'improved'; 'always controlled'; 'always uncontrolled'; and 'worsened'. Results The median nerve at mid-forearm (MN-f), the ulnar nerve at mid-forearm (UN-f) and at distal arm (UN-a) were significantly reduced after 1-year follow-up in all patients (P <0·001, P <0·008, P <0·012, respectively). In the 'improved' group, there was a significant reduction of median nerve CSA examined at mid-forearm (MN-f) (P = 0·02), and distal arm ulnar nerve CSA (UN-a) (P = 0·002). In the other groups no statistically significant differences in ultrasound parameters were recorded. However, UN-a, UN-f, MN-f, MN-ct were still significantly higher in all groups compared with controls (P <0·001). Conclusion These data demonstrate that median and ulnar nerves CSA are reduced after 1 year follow-up, in line with the reduction of GH/IGF-I levels. However, as the control of the disease incompletely reverts nerve enlargement, this phenomenon could be only partially reversible.