Purpose: To determine the accuracy of manufacturer models and difference in ice ball dimensions from the first to second freeze cycles during cryoablation of renal cell carcinoma (RCC). Methods: All patients who underwent cryoablation for RCC and had either a uniform type of needle placed in a pattern consistent with manufacturer provided data (n = 48) or computed tomography performed during the first and second freeze cycles (n = 28) were retrospectively reviewed. Ice ball measurements were made in relationship to the cryoablation probes. Factors which may affect the manufacturer prediction or change in the size of the ice ball from first to second freeze cycles were evaluated. Results: The visualized ice ball was significantly smaller than predicted in the long axis (LA) (Visualized: 29 mm ± 8; Predicted: 54 mm ± 7; p < 0.001), perpendicular transverse (PTR) (Visualized: 31 mm ± 7; Predicted: 52 mm ± 6; p < 0.001) and perpendicular craniocaudal (PCC) (Visualized: 30 mm ± 8; Predicted: 50 mm ± 7; p < 0.001). Furthermore, in the LA, PTR and PCC directions the achieved ice ball size was significantly closer to the predicted size as the total number of probes increased (p = 0.006, p = 0.048 and p = 0.023, respectively). The ice ball was significantly larger in the LA (3 mm (range: −7, 14 mm), p < 0.001), PTR (3 mm (range: −4, 11 mm), p < 0.001), and PCC (3 mm (range: 0, 26 mm), p < 0.001) dimensions on the second as compared to the first freeze cycle. Conclusion: The manufacturer provided model overestimates the size of the visualized Ice ball and Ice balls formed on the second freeze are significantly larger (median 3 mm) than those formed on the first freeze.
Bibliographical noteFunding Information:
Research reported in this publication was supported by NIH grant P30 CA77598 utilizing the Biostatistics and Bioinformatics Core shared resource of the submitting institution and by the National Center for Advancing Translational Sciences of the National Institutes of Health Award Number UL1TR000114 . The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
© 2022 Elsevier Inc.
- Ablation zone
- Renal cell carcinoma
PubMed: MeSH publication types
- Journal Article