Patients' radiation dose in computed tomography-fluoroscopy-guided percutaneous cryoablation for small renal tumors. Issue 144 (November 2021)

• Record Type: Journal Article
• Authors: Fukushima, Yasuhiro; Nakamura, Junpei; Seki, Yuko; Ando, Masashi; Miyazaki, Masaya; Tsushima, Yoshito
• Is Part Of: European journal of radiology. Issue 144(2021)
• Publication Date: 2021-11
• Subjects: Cryoablation -- Computed tomography-fluoroscopy -- Spiral scan -- Radiation dose -- Skin dose -- Renal tumour; CT computed tomography -- CTDIvol volume computed tomography index -- DLP dose-length product -- SSDE size-specific dose estimates -- ESD entrance skin dose; Medical radiology -- Periodicals; Radiology -- Periodicals; Radiologie médicale -- Périodiques; Medical radiology; Periodicals; 616.075705
• DOI: 10.1016/j.ejrad.2021.109972
• Languages: English
• ISSNs: 0720-048X

Abstract

Highlights: Patients' radiation dose in CT-guided cryoablation is mostly due to CT-fluoroscopy. The patient's dose should be assessed by SSDE, not CTDIvol. Hydro- and/or pneumodissection results in a higher patient's skin dose. The patient's skin dose increases with the number of cryoneedle punctures. The patient's skin dose is<1 Gy, and skin damage will not occur. Abstract: Purpose: This study aimed to evaluate patients' radiation dose in computed tomography (CT)-fluoroscopy-guided cryoablation for small renal tumors and assess the possible factors affecting it. Methods: In our institution, cryoablation was performed in 152 patients between 2013 and 2020. Procedures that were not for renal tumors and did not have radiation dose records and detailed information were excluded from the analysis. The size-specific dose estimates (SSDE), volume CT dose index (CTDIvol ), dose-length product (DLP), and entrance skin dose (ESD) were evaluated for both spiral scan and CT-fluoroscopy. The effects of the number of cryoneedle punctures; combined use of hydro- and/or pneumodissection procedures; patients' characteristics, such as body-mass index (BMI); and the tumor-related factors, such as tumor location, were determined by the univariate and multivariate analyses. Results: In the 72 included procedures, the median SSDE was 658 mGy and the median CTDIvol was 456 mGy. The median percentage dose of CT-fluoroscopy to the total procedure dose was estimated as 89.8% (591/658 mGy) with SSDE and 41.4% (611/1, 475 mGy cm) with DLP. The combined use of hydro- and/or pneumodissection and number of cryoneedle punctures were significantly associated with the total ESD, and the maximum total ESD was 863 mGy in our cases. Conclusions: Using SSDE as an index, 89.8% of patients' radiation dose was attributed to CT-fluoroscopy, and ESD for the total procedure did not exceed 1 Gy. The increased number of cryoneedle punctures and combined use of hydro- and/or pneumodissection increased the total ESD.