Goldberg S N, Hahn P F, Halpern E F, Fogle R M, Gazelle G S
Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
Radiology. 1998 Dec;209(3):761-7. doi: 10.1148/radiology.209.3.9844671.
To determine whether vasoactive pharmacologic agents can alter radio-frequency (RF)-induced coagulation necrosis by modulating hepatic blood flow.
RF ablation was performed in normal, in vivo porcine liver with 1.5-cm internally cooled electrodes and a standardized RF application (i.e., 500 mA for 10 minutes). Ablation was performed without (n = 9) and with pharmacologic modulation of blood flow with halothane (n = 7), vasopressin (n = 6), or epinephrine (n = 7). Laser Doppler techniques were used to quantify changes in hepatic blood flow. Remote thermometry was also performed. Blood flow was correlated with both induced coagulation necrosis and tissue temperatures.
Halothane reduced mean blood flow (+/- SD) to 46.1% +/- 8.5 of normal, and vasopressin increased mean blood flow to 132.7% +/- 13.9. Epinephrine caused increased hepatic blood flow centrally (171.1% +/- 31.7) but not peripherally (102.8% +/- 15.4). Mean coagulation diameter was 1.4 cm +/- 0.3 with vasopressin, 2.2 cm +/- 0.4 with normal blood flow, and 3.2 cm +/- 0.1 with halothane (P < .01). After epinephrine infusion, mean coagulation measured 2.3 cm +/- 0.3 peripherally and 1.4 cm +/- 0.5 centrally (P < .01). A linear correlation between coagulation diameter and blood flow was demonstrated (r2 = 0.78). Temperatures 10 and 15 mm from the electrode correlated with both blood flow and coagulation diameter (r2 = 0.65 and 0.60, respectively).
The coagulation necrosis achieved for a standardized RF application correlates with relative tissue perfusion. Pharmacologic reduction of blood flow during thermally mediated percutaneous ablation may induce greater coagulation necrosis.
通过调节肝血流来确定血管活性药物是否能够改变射频（RF）诱导的凝固性坏死。
采用1.5厘米内部冷却电极及标准化射频应用（即500毫安，持续10分钟），在正常的活体猪肝中进行射频消融。在未进行血流药理学调节（n = 9）以及使用氟烷（n = 7）、血管加压素（n = 6）或肾上腺素（n = 7）进行血流药理学调节的情况下进行消融。使用激光多普勒技术量化肝血流的变化。还进行了远程温度测量。血流与诱导的凝固性坏死及组织温度相关。
氟烷将平均血流（±标准差）降至正常的46.1%±8.5%，血管加压素将平均血流增加至132.7%±13.9%。肾上腺素使肝脏中心血流增加（171.1%±31.7%），但外周血流未增加（102.8%±15.4%）。血管加压素作用下的平均凝固直径为1.4厘米±0.3厘米，正常血流时为2.2厘米±0.4厘米，氟烷作用下为3.2厘米±0.1厘米（P <.01）。输注肾上腺素后，外周平均凝固直径为2.3厘米±0.3厘米，中心为1.4厘米±0.5厘米（P <.01）。凝固直径与血流之间呈线性相关（r2 = 0.78）。距电极10毫米和15毫米处的温度与血流及凝固直径均相关（分别为r2 = 0.65和0.60）。
标准化射频应用所实现的凝固性坏死与相对组织灌注相关。热介导经皮消融过程中血流的药理学减少可能会诱导更大范围的凝固性坏死。
