Benjamin H Ge1, Thomas J Guzzo2, Gregory J Nadolski1, Michael C Soulen1, Timothy W I Clark1, Stanley B Malkowicz2, Alan J Wein2, Stephen J Hunt1, S William Stavropoulos3. 1. Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce St., 1 Silverstein, Philadelphia, PA 19104. 2. Department of Urology, Hospital of the University of Pennsylvania, 3400 Spruce St., 1 Silverstein, Philadelphia, PA 19104. 3. Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce St., 1 Silverstein, Philadelphia, PA 19104. Electronic address: stav@uphs.upenn.edu.
Abstract
PURPOSE: To determine if CT characteristics of intraprocedural ice balls correlate with outcomes after cryoablation. MATERIALS AND METHODS: A retrospective review was performed on 63 consecutive patients treated with renal cryoablation. Preprocedural and intraprocedural images were used to identify the size and location of renal tumors and ice balls as well as the tumor coverage and ice-ball margins. Review of follow-up imaging (1 mo and then 3-6-mo intervals) distinguished successful ablations from cases of residual tumor. RESULTS: Patients who underwent successful ablation (n = 50; 79%) had a mean tumor diameter of 2.5 cm (range, 0.9-4.3 cm) and mean ice-ball margin of 0.4 cm (range, 0.2-1.2 cm). Patients with residual tumor (n = 13; 21%) had a mean tumor diameter of 3.8 cm (range, 1.8-4.5 cm) and mean ice-ball margin of -0.4 cm (range, -0.9 to 0.4 cm). Residual and undertreated tumors were larger and had smaller ice-ball margins than successfully treated tumors (P < .01). Ice-ball diameters were significantly smaller after image reformatting (P < .01). Ice-ball margins of 0.15 cm had 90% sensitivity, 92% specificity, and 98% positive predictive value for successful ablation. Success was independent of tumor location or number of cryoprobes. CONCLUSIONS: Ice-ball margin and real-time intraprocedural reformatting could be helpful in predicting renal cryoablation outcomes. Although a 0.5-cm margin is preferred, a well-centered ice ball with a short-axis margin greater than 0.15 cm strongly correlated with successful ablation.
PURPOSE: To determine if CT characteristics of intraprocedural ice balls correlate with outcomes after cryoablation. MATERIALS AND METHODS: A retrospective review was performed on 63 consecutive patients treated with renal cryoablation. Preprocedural and intraprocedural images were used to identify the size and location of renal tumors and ice balls as well as the tumor coverage and ice-ball margins. Review of follow-up imaging (1 mo and then 3-6-mo intervals) distinguished successful ablations from cases of residual tumor. RESULTS:Patients who underwent successful ablation (n = 50; 79%) had a mean tumor diameter of 2.5 cm (range, 0.9-4.3 cm) and mean ice-ball margin of 0.4 cm (range, 0.2-1.2 cm). Patients with residual tumor (n = 13; 21%) had a mean tumor diameter of 3.8 cm (range, 1.8-4.5 cm) and mean ice-ball margin of -0.4 cm (range, -0.9 to 0.4 cm). Residual and undertreated tumors were larger and had smaller ice-ball margins than successfully treated tumors (P < .01). Ice-ball diameters were significantly smaller after image reformatting (P < .01). Ice-ball margins of 0.15 cm had 90% sensitivity, 92% specificity, and 98% positive predictive value for successful ablation. Success was independent of tumor location or number of cryoprobes. CONCLUSIONS: Ice-ball margin and real-time intraprocedural reformatting could be helpful in predicting renal cryoablation outcomes. Although a 0.5-cm margin is preferred, a well-centered ice ball with a short-axis margin greater than 0.15 cm strongly correlated with successful ablation.
Authors: Matthew Seager; Shankar Kumar; Emma Lim; Graham Munneke; Steve Bandula; Miles Walkden Journal: Br J Radiol Date: 2020-09-22 Impact factor: 3.039
Authors: Christiaan G Overduin; Sjoerd F M Jenniskens; J P Michiel Sedelaar; Joyce G R Bomers; Jurgen J Fütterer Journal: Eur Radiol Date: 2017-04-13 Impact factor: 5.315