聚焦激光消融（FLA）是前列腺癌（PCa）的靶向治疗。临床研究表明，在纤维配置一致的情况下，消融体积存在显着差异。因此，需要一个预测模型来安全应用 FLA 治疗 PCa。本研究旨在使用临床激光治疗方案在受控离体实验中评估 FLA 诱导的温度分布的可重复性。此外，它还试图检验 CEM43 模型在预测不可逆损伤区 (ZID) 方面的有效性，并将这些结果与 Arrhenius 模型得出的结果进行比较。新鲜切除的死后人类前列腺和猪肝脏标本用于受控离体消融。将组织固定在有机玻璃样品架中，以精确放置激光光纤和热电偶。 FLA 使用 1064 nm Nd:YAG 激光器在 3 W 下以连续波模式进行 10 分钟。获得 FLA 之前和之后的 3D T1 加权 7 T MRI 扫描来评估治疗区域。制备全封固苏木精和曙红组织学载玻片并数字化。在组织学上，ZID 被定义为汽化、碳化和凝固组织的总和。使用双三次插值根据温度数据创建二维热发展图。应用 43°C 分钟累积等效热等效应剂量 (CEM43) 模型来预测 ZID，并使用 240 当量分钟 (240-CEM43) 作为损伤阈值。此外，还使用阿伦尼乌斯热模型来比较 CEM43 结果。将预测的 ZID 与 MRI 和组织学进行比较。对离体人前列腺样本 (n = 2) 和猪肝脏样本 (n = 5) 进行 FLA 处理。对于人类前列腺组织，FLA 不会导致组织学肉眼检查或 MRI 损伤时可识别的 ZID。在 FLA MRI 上，离体猪肝脏样本显示激光光纤尖端周围有一个界限清晰的椭圆形高信号病变。 MRI 病变（范围 1.6-2.1cm2）与组织学上 ZID 的形状和位置相对应，但较小（中位数 1.7 vs. 3.2，p= 0.02）。猪肝脏样本的组织学检查显示 ZID 范围为 2.1 至 4.1 cm2，而 240-CEM43 预测的 ZID 范围为 3.3 至 3.8 cm2。尽管 240-CEM43 预测的 ZID 中位数并不显着大于组织学 ZID（3.8 vs. 3.2cm2，p=0.22），但在大多数实验中它倾向于高估组织学结果。阿伦尼乌斯预测的 ZID 中位数与组织学 ZID 相似（3.2 vs. 3.2 cm2，p = 0.56），但在比较各个实验时大小有所不同（范围 2.5-3.2 cm2）。离体人类前列腺上的 FLA 未显示出热损伤组织病理学或 MRI。离体猪肝 FLA 导致组织学上可识别的 ZID 和 MRI 上的病变。 240-CEM43 通常高估了 ZID，并且与组织学相比变异性较小。阿伦尼乌斯模型的结果与组织学结果更加一致，但仍然无法预测个体 FLA 引起的组织学热损伤。实验间 ZID 变异性强调需要为 PCa 治疗中的 FLA 开发更全面的预测剂量测定模型。© 2024 作者。 《激光在外科和医学中的应用》由 Wiley periodicals LLC 出版。

Focal laser ablation (FLA) serves as a targeted therapy for prostate cancer (PCa). Clinical studies have demonstrated significant variations in ablation volumes with consistent fiber configurations. Consequently, a prediction model is needed for the safe application of FLA in treating PCa.This study aimed to evaluate the reproducibility of FLA-induced temperature profiles in controlled ex vivo experiments using clinical laser treatment protocols. Additionally, it sought to examine the effectiveness of the CEM43 model in predicting the zone of irreversible damage (ZID) and to compare these findings with outcomes derived from the Arrhenius model.Freshly excised postmortem human prostate and porcine liver specimens were used for controlled ex vivo ablation. Tissues were secured in a Perspex sample holder for precise placement of the laser fiber and thermocouples. FLA was conducted with a 1064-nm Nd:YAG laser at 3 W in continuous-wave mode for 10 min. Pre- and post-FLA 3D T1-weighted 7 T MRI scans were obtained to assess the treatment area. Whole-mount hematoxylin and eosin histological slides were prepared and digitized. On histology, the ZID was defined as the total of vaporized, carbonized, and coagulated tissue. A 2D thermal development map was created from temperature data, using bi-cubic interpolation. The cumulative equivalent thermal isoeffect dose at 43°C in minutes (CEM43) model was applied to predict the ZID, with 240 equivalent minutes (240-CEM43) used as the damage threshold. Additionally, the Arrhenius thermal model was used for comparison of CEM43 results. Predicted ZIDs were compared to MRI and histology.FLA treatment was performed on ex vivo human prostate samples (n = 2) and porcine liver specimens (n = 5). For human prostate tissue, FLA did not result in an identifiable ZID upon histological macroscopic examination or a lesion on MRI. Ex vivo porcine liver samples showed a clearly demarcated oval-shaped hyperintense lesion surrounding the laser fiber tip on post-FLA MRI. The MRI lesion (range 1.6-2.1 cm2) corresponded with the shape and location of the ZID on histology, but was smaller (median 1.7 vs. 3.2, p = 0.02). Histological examination of porcine liver samples revealed ZIDs ranging from 2.1 to 4.1 cm2, whereas 240-CEM43-predicted ZIDs ranged from 3.3 to 3.8 cm2. Although the median 240-CEM43-predicted ZID was not significantly larger than the histology ZID (3.8 vs. 3.2 cm2, p = 0.22), it tended to overpredict the histological results in most experiments. The median Arrhenius-predicted ZID was similar to the histological ZID (3.2 vs. 3.2 cm2, p = 0.56), but varied in size when comparing individual experiments (range 2.5-3.2 cm2).FLA on ex vivo human prostate showed no thermal damage on histopathology or MRI. Ex vivo porcine liver FLA resulted in identifiable ZID on histology and lesions on MRI. 240-CEM43 generally overestimated the ZID and had less variability compared to histology. Results from the Arrhenius model were in better agreement with the histology findings, but still did not predict the individual FLA-induced histological thermal damage. Inter-experiment ZID variability underlines the need for developing a more comprehensive predictive dosimetry model for FLA in PCa treatment.© 2024 The Author(s). Lasers in Surgery and Medicine published by Wiley Periodicals LLC.