Ice ball size and temperature change during cryoablation in a lard and an ethiodized-oil tissue phantom

Nai-Wen Chang; Shu-Huei Shen; Chien-An Liu; Felix Antony Halim; Jia-An Hong; Chih-Chien Li; Ping-Lang Yen

doi:10.1016/j.cryobiol.2025.105274

Ice ball size and temperature change during cryoablation in a lard and an ethiodized-oil tissue phantom

Cryobiology. 2025 Jun 4:120:105274. doi: 10.1016/j.cryobiol.2025.105274. Online ahead of print.

Authors

Nai-Wen Chang¹, Shu-Huei Shen², Chien-An Liu¹, Felix Antony Halim³, Jia-An Hong¹, Chih-Chien Li¹, Ping-Lang Yen³

Affiliations

¹ Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.
² Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan. Electronic address: shshen2003@gmail.com.
³ Department of Biomechatronics Engineering, National Taiwan University, Taipei, Taiwan.

PMID: 40472720
DOI: 10.1016/j.cryobiol.2025.105274

Abstract

This in vitro study evaluates the effects of varying concentrations of lard and ethiodized-oil (Lipiodol) on temperature changes and ice ball diameters during cryotherapy. A phantom was constructed using six glass bottles, one filled with 0.9 % normal saline (NS) and the others containing agar phantoms mixed with different proportions of lard and NS (0 %, 10 %, 40 %, 70 %, and 100 % lard). Similarly, a phantom was prepared with ethiodized-oil. Six cryoprobes were inserted into the bottles, and freezing was initiated simultaneously, with temperature readings recorded every 10 s over a 9-min freezing period. CT scans were performed before freezing and at 3, 6, and 9 min post-freezing to measure ice ball diameters, with each phantom undergoing a single freezing cycle. Phantoms with lard or ethiodized-oil showed increased freezing rates with higher concentrations, stabilizing at approximately -140 to -150 °C. The largest ice ball diameters were observed in the 0 % and 10 % lard and ethiodized-oil phantoms. Negative correlations were identified between ice ball diameter and lard concentration at 3, 6, and 9 min (R² = 0.910, 0.838, 0.778; p = 0.008, 0.019, 0.030), as well as between ice ball diameter and ethiodized-oil concentration at 6 min (R² = 0.881; p = 0.040). These results suggest that distinct concentrations of lard and ethiodized-oil significantly influence the temporal temperature changes and ice ball dimensions during cryotherapy.

Keywords: Cryotherapy; Ethiodized-oil; Ice ball size; Lard; Temperature change.