Ultrasound findings of carpal tunnel syndrome in a hunter syndrome patient

We read with great interest the study by Alkhachroum and Preston about ultrasonographic (US) findings of carpal tunnel syndrome (CTS) in the case of a 40-yearold patient affected by mucopolysaccharidosis II. 1 The patient was evaluated by clinical, neurophysiological, and US examinations. He presented with pain and electric shocks in the fingers since childhood, with worsening during the preceding year. Neurophysiological study showed severe involvement of the median nerve at the wrist with absence of the compound muscle action potential from abductor pollicis brevis and absent sensory nerve action potential. This assessment could not localize the precise site of the lesion. US revealed median nerve involvement (i.e., marked enlargement of cross-sectional area) at the distal wrist. Another notable US finding was the hyperechoic US pattern of the nerve between forearm and wrist.