INTERVENTIONAL Florian Streitparth & Tony Hartwig & Thula Walter & Maximilian De Bucourt & Michael Putzier & Patrick Strube & Tina Bretschneider & Patrick Freyhardt & Martin Maurer & Diane Renz & Bernhard Gebauer & Bernd Hamm & Ulf K. M. Teichgräber Received: 3 December 2012 / Revised: 17 March 2013 / Accepted: 21 March 2013 / Published online: 9 May 2013 # European Society of Radiology 2013 Abstract Objectives To assess the feasibility, safety and efficacy of real-time MR guidance and thermometry of percutaneous laser disc decompression (PLDD). Methods Twenty-four discs in 22 patients with chronic low- back and radicular pain were treated by PLDD using open 1.0- T magnetic-resonance imaging (MRI). A fluoroscopic proton- density-weighted turbo spin-echo (PDw TSE) sequence was used to position the laser fibre. Non-spoiled gradient-echo (GRE) sequences were employed for real-time thermal mon- itoring based on proton resonance frequency (PRF). Radicular pain was assessed over 6 months with a numerical rating scale (NRS). Results PLDD was technically successful in all cases, with adequate image quality for laser positioning. The PRF-based real-time temperature monitoring was found to be feasible in practice. After 6 months, 21 % reported complete remission of radicular pain, 63 % at least great pain relief and 74 % at least mild relief. We found a significant decrease in the NRS score between the pre-intervention and the 6-month follow-up assess- ment (P <0.001). No major complications occurred; the single adverse event recorded, moderate motor impairment, resolved. Conclusions Real-time MR guidance and PRF-based ther- mometry of PLDD in the lumbar spine under open 1.0-T MRI appears feasible, safe and effective and may pave the way to more precise operating procedures. Key Points • Percutaneous laser disc decompression (PLDD) is in- creasingly used instead of conventional surgery . • Open 1.0-T MRI with temperature mapping seems techni- cally successful in monitoring PLDD. • Pain relief was at least ‘great’ in 64 % of patients. • No major complications occurred. • Open 1.0-T MRI appears a safe and effective option for patient-tailored PLDD. Keywords Low back pain . Radiculopathy . Spine . PLDD . Open MRI Abbreviations FOV Field of view FSE Fast spin echo GRE Gradient echo NRS Numerical rating scale NSA Number of signal averages PDw Proton-density-weighted PLDD Percutaneous laser disc decompression PRF Proton resonance frequency SD Standard deviation F. Streitparth (*) : T. Walter : M. De Bucourt : P. Freyhardt : M. Maurer : D. Renz : B. Gebauer : B. Hamm : U. K. M. Teichgräber Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin, Germany e-mail: florian.streitparth@charite.de T. Hartwig : M. Putzier : P. Strube Center for Musculoskeletal Surgery, Charité, Humboldt-University, Berlin, Germany T. Bretschneider Department of Radiology, University of Magdeburg, Magdeburg, Germany Eur Radiol (2013) 23:2739–2746 DOI 10.1007/s00330-013-2872-4 MR guidance and thermometry of percutaneous laser disc decompression in open MRI: an initial clinical investigation