Discussion
Image-guided muscle biopsy is performed at multiple institutions globally, utilising either MRI or sonographic guidance \cite{Lindequist_1990} \cite{Lassche_2014}. However, current evidence demonsrates that sonographic-guidance is associated with fewer bleeding complications and is more cost-effective than utilisation of MRI due to the longer procedure time and use of disposable materials \cite{Lassche_2014}. Current studies have not utilised a modified Bergström needle technique in combination with ultrasound guidance, and therefore our data set is the first to evaluate the use of this approach with ultrasound.
Ultrasound-guided per cutaneous muscle biopsy has been demonstrated to provide diagnostic rates comparable to open biopsy in the assessment of acute muscle disease but less successful for chronic disease \cite{O_Sullivan_2006} . Furthermore, this technique conveys further practical benefits : the modified Bergström needle and suction technique is best utilised for difficult to access muscle groups that cannot be targeted using an open approach , requires a smaller incision and reduces use of surgical theatre time. The procedure is also rapid and can be performed in an outpatient setting under local anaesthesia. Visualisation of key structures minimises the risk of post procedural bleeding. Additionally, the procedure is better tolerated by patients in comparison to surgical methods.
Furthermore, from a operational perspective, it is more feasible to allocate these procedures on an ultrasound list without impacting modality demand, in comparison to utilising MRI, when most departmental MRI scanners are used to near maximal capacity, and therefore this could create additional patient back-logs.