Feasibility of MR Imaging– guided Percutaneous Drainage of Pancreatic Fluid Collections Juho Kariniemi, MD, Roberto Blanco Sequeiros, MD, Risto Ojala, MD, and Osmo Tervonen, MD PURPOSE: To assess the feasibility and safety of magnetic resonance (MR) imaging– guided percutaneous drainage of pancreatic fluid collections in an open configuration low field MR imaging system. MATERIALS AND METHODS: Ten patients with pancreatic fluid collections were examined prospectively. Five of the fluid collections were symptomatic pseudocysts and five were pancreatic abscesses. All percutaneous drainages were performed solely under MR imaging guidance with a 0.23-T open configuration C-arm shaped MR imaging scanner with interventional optical tracking. Every step of the procedure was monitored using balanced fast field echo sequences. In each case, the drainage of the fluid collection was performed with a MR imaging– compatible drainage kit using the Seldinger technique. The kit included an 18-gauge needle, a 0.035-inch stiff guide wire, 6-F and 8-F dilators, and an 8-F pigtail drainage catheter. RESULTS: All drainage catheters could successfully be placed into the pancreatic fluid collections under MR imaging guidance. Visualization of the needle, dilator, and drainage catheter was excellent. However, visualization of the guide wire was suboptimal. The mean time needed for the MR– guided drainage procedure was 44 minutes. No immediate complications occurred. The clinical success rate of the percutaneous drainage was 70%; three patients were subse- quently treated surgically. There were no deaths. The average duration of catheterization was 40 days. CONCLUSION: MR imaging– guided percutaneous drainage of pancreatic fluid collections is feasible and safe. The presented technique has limitations—lack of real-time imaging control and small selection of MR imaging– compat- ible devices—that necessitate further technical developments before the procedure can be recommended for routine clinical use. J Vasc Interv Radiol 2006; 17:1321–1326 Abbreviation: b-FFE = balanced fast field echo DEVELOPMENT of a pancreatic fluid collection is a common complication of either acute or chronic pancreatitis. There are many different types of pan- creatic fluid collections, and their management depends on a number of factors, but the main principle is that all fluid collections that are symptom- atic must be drained. The interven- tional options include endoscopic (1– 3), percutaneous (4 –7), and surgical (8 –10) drainage, as well as a combina- tion of these (11–13). The choice of treatment is based on several factors concerning both the patient and the fluid collection; however, in selected patients percutaneous drainage is the procedure of choice (6,14 –16). The standard imaging modalities used for guiding percutaneous drain- age of pancreatic fluid collections are computed tomography (CT) and ultra- sonography (US), the latter sometimes combined with x-ray fluoroscopy (6,17–20). Magnetic resonance (MR) imaging with its superior soft tissue contrast, multiplanarity, and lack of ionizing radiation already has a vari- ety of well-established percutaneous interventional applications (21–28), but experience in MR imaging– guided drainage is very limited. Three pre- liminary reports in a small number of patients with heterogeneous fluid col- lections, including one pancreatic pseudocyst, have demonstrated the initial feasibility of MR imaging– guid- ance alone (29,30) or in conjunction with fluoroscopy (31) in percutaneous drainages. The purpose of this study was to test the feasibility and safety of MR imaging– guided percutaneous drainage of pancreatic fluid collections in an open-configuration, low-field MR imaging system. From the Department of Radiology, Oulu University Hospital, 90029, P.O. Box 50, Oulu, Finland (J.K., R.B.S, R.O., O.T.), and the Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA (R.B.S). Re- ceived December 13, 2005; revision requested March 26, 2006; final revision received and accepted May 29. Address correspondence to J.K.; E-mail: juho. kariniemi@oulu.fi None of the authors have identified a conflict of interest. © SIR, 2006 DOI: 10.1097/01.RVI.0000231957.91785.63 1321