台中童綜合醫院 外科部 泌尿科
Hounsfield unit (HU) value and its correlation with Indocyanine Green (ICG) in patient receiving Robotic-assisted Adrenalectomy
Pin-Chun Liu, Yi-Sheng Lin, Wei-Chun Weng, Li-Hua Huang, Chao-Yu Hsu, Min-Che Tung, Yen-Chuan Ou
Division of Urology, Department of Surgery
Tungs’ Taichung MetroHarbor Hospital, Taichung, Taiwan
Purpose: The utility of indocyanine green (ICG) in guidance of surgery has been reported widely in recent years. ICG has been used for differentiation of tumor and parenchymal tissue during adrenalectomy. The purposes of this study is to evaluate the correlation between Hounsfield unit (HU) value and effectiveness of ICG fluorescence.
Materials and Methods: We retrospectively reviewed abdomen computed tomography performed in patients receiving ICG fluorescence guidance robotic-assisted unilateral adrenalectomy from 2016 to 2020 by single surgeon. Pre-contrast and post-contrast HU value were measured at the center of adrenal mass. The HU difference before and after contrast was calculated. If the tumor border can be visualized after ICG injection, it would belong to the ICG positive group. The others would be categorized to ICG negative group. Perioperative outcomes were collected and analyzed. Two groups were analyzed by Mann-Whitney U test under SPSS software. P<0.05 would be considered as significance.
Results: There were a total 8 patients received ICG fluorescence guidance robotic-assisted adrenalectomy. 7 patients can identify mass and adrenal tissue after ICG injection (ICG positive) and 1 patient reported failures to identify neoplastic tissue (ICG negative). There was no significant difference between the pre- and post-contrast HU value difference (27.28 vs 33, p=0.750).
Conclusions: This retrospective study suggested that the pre- and post-contrast difference of HU value cannot be used to predict the effectiveness of ICG fluorescence in adrenalectomy. However, more research is needed to identify the relationships between HU and ICG fluorescence.