Ct somatom sensation open

All cryoablation procedures were performed, or supervised, by an expert interventional radiologist with 4 to 12 years of experience in thermal ablation. General or epidural anesthesia was administered, and computed tomography (CT) guidance (CT Somatom Sensation Open, Siemens®, Munchen, Germany) was used for realtime evaluation of the procedure. Cryoablation was performed using the Visual ICE™ system (Boston Scientific, USA) with IceForce® or IcePearl® cryoprobes. The number of cryoprobes was determined by the size of the lesion, and inserted with 1 to 2 cm spacing. If deemed necessary, air- or hydrodissection was applied to protect adjacent structures using room air or 5% glucose solution combined with iodine contrast. At least two cycles of freezing, passive thawing, and active thawing were completed with a minimum time of 10 min, 2 min, and 2 min, respectively. Technical success was achieved if the ice-ball had a minimum margin of 10 mm in three dimensions on the periprocedural CT images. Patients stayed overnight for monitoring and were discharged the day after the cryoablation procedure.

All patients were first discussed in a multidisciplinary tumour board, consisting of urologists, radiologists and medical oncologists to decide patients eligibility for MWA. The MW procedures were performed computed tomography (CT) guided (CT Somatom Sensation Open, Siemens^®, Munchen, Germany). Patients were treated with two different MW systems (2012–2014: Evident^® MW system (Covidien^®, Dublin, Ireland), 2014–2018: Emprint^® MW system (Medtronic^®, Dublin, Ireland)). Dissection was performed with 5% glucose solution plus 10% iodinated contrast, CO2 and room air for tumours adjacent to vulnerable structures. Ureteric perfusion with cooled saline was used for tumours close to the collection system and the proximal ureter. Antenna placement was performed with CT fluoroscopy, and optimal position was verified by CT before start of the ablation. After antenna placement, biopsy was performed. In principle, a power of 100 W was used for 2–10 min according to tumour size. A margin of 5–10 mm was attempted to achieve complete ablation. Fluoroscopic CT check was performed to monitor the procedure. In larger tumours, the ablation was repeated with different antenna positions to achieve a complete ablation zone. With the Evident^® MW system, multiple antennas were placed in the tumour according to physicians choice.