Acrel’s “ganglion” is a controversial structure found towards the dorsum of the wrist. It is thought to be either the distal swelling of the posterior interosseous nerve or even a cystic tumour on an extensor tendon of the wrist named after the Swedish surgeon Olof af Acrel in the 18th century. The function and exact location of this swelling remain a mystery within published literature. It has been in the past a target for anaesthetic blocks; however histological studies suggest it to be devoid of nerve cell bodies; hence it is deemed to be a 'pseudoganglion'. This study aims to determine the possibility of identifying Acrel’s “ganglion” using ultrasound. Ten wrists were examined and compared using a GE LOGIQ e ultrasound system with a 12L-RS transducer. A hypoechoic structure was found within the fourth extensor compartment in all the wrists investigated. Our findings suggest that a structure located in the described site of Acrel’s “ganglion” appears to be hypoechoic, contrary to the typical hyperechoic appearance of a nerve. It is possible to visualize Acrel’s “ganglion” using ultrasound. Our findings also back up histological studies indicating it is not the termination of the posterior interosseous nerve. Documentation of the exact location of this pseudoganglion has clinical implications. Future studies should focus on the benefits of introducing an aesthetic agent in a precise location rather than distal part of interosseous nerve as there are probably no cell bodies at this location.