Ultrasound image of the carpal tunnel in the axial plane during Step 7 of the hydrodissection. The median nerve is fully dissected from the flexor retinaculum. The anechoic fluid (on this image a layer of approximately 4 mm) between the retinaculum and the median nerve is the injected solution. Legend: circle in dotted line: median nerve; void arrows: flexor retinaculum or transverse carpal ligament