MR-guided percutaneous drainage of abdominal fluid collections in combination with X-ray fluoroscopy: initial clinical experience

The aim of this study was to examine the feasibility of a hybrid interventi onal MR system, which combines a closed bore magnet with a C-arm fluoroscop y unit for percutaneous drainage of abdominal fluid collections. During the past 2 years, we have performed four drainage procedures in four patients (mean age 47 years). Three patients had abscesses (psoas muscle, kidney, su bphrenic location) and the fourth patient had a recurrent splenic cyst. All procedures were performed on an interventional MR system consisting of a 1 .5-T ACS-NT scanner combined with a specially shielded C-arm. The drainages were guided by T1-weighted fast gradient-echo images, T2-weighted single-s hot turbo spin-echo images or both. A standard 18 G (1.2 mm) nonferromagnet ic stainless steel needle with a Teflon sheath was used for the punctures f ollowing which a 0.89 mm nitinol guidewire was inserted into the fluid coll ection. Thereafter, the patient was positioned in the immediate adjacent fl uoroscopy unit and a drainage catheter was placed under fluoroscopic contro l. All drainage catheters were successfully placed into the fluid collectio ns, as proven by fluid aspiration and resolution of the collection. The mea n time needed for the entire drainage procedure (MR and fluoroscopy) was 11 0 min. No procedure-related complications occurred. It is feasible to perfo rm drainage procedures on a closed-bore MR scanner. The multiplanar imaging capabilities of MR are particularly helpful for fluid collections in the s ubphrenic location.