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

We have previously demonstrated peripheral nerve enlargement in acromegaly.

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.

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.

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'.

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).

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.