Bak Jinoh, Kang Hyun Wook
Department of Biomedical Engineering, Pukyong National University, 45 Yongso-ro Nam-gu, Busan, 48513, Republic of Korea.
Center for Marine-Integrated Biomedical Technology (BK21 Plus), Pukyong National University, Busan, South Korea.
Lasers Med Sci. 2017 Jul;32(5):993-999. doi: 10.1007/s10103-017-2199-5. Epub 2017 Mar 29.
Esophageal stricture occurs in 7-23% of patients with gastroesophageal reflux disease. However, the current treatments including stent therapy, balloon dilation, and bougienage involve limitations such as stent migration, formation of the new strictures, and snowplow effect. The purpose of the current study was to investigate the feasibility of structural expansion in tubular tissue ex vivo during temperature-monitored photothermal treatment with a diffusing applicator for esophageal stricture. Porcine liver was used as an ex vivo tissue sample for the current study. A glass tube was used to maintain a constant distance between the diffuser and tissue surface and to evaluate any variations in the luminal area after 10-W 1470-nm laser irradiation for potential stricture treatment. The 3D goniometer measurements confirmed roughly isotropic distribution with less than 10% deviation from the average angular intensity over 2π (i.e., 0.86 ± 0.09 in arbitrary unit) from the diffusing applicator. The 30-s irradiation increased the tissue temperature up to 72.5 °C, but due to temperature feedback, the interstitial tissue temperature became saturated at 70 °C (i.e., steady-state error = ±0.4 °C). The irradiation times longer than 5 s presented area expansion index of 1.00 ± 0.04, signifying that irreversible tissue denaturation permanently deformed the lumen in a circular shape and secured the equivalent luminal area to that of the glass tube. Application of a temperature feedback controller for photothermal treatment with the diffusing applicator can regulate the degree of thermal denaturation to feasibly treat esophageal stricture in a tubular tissue.
食管狭窄发生在7%至23%的胃食管反流病患者中。然而，目前的治疗方法，包括支架治疗、球囊扩张和探条扩张，存在诸如支架迁移、新狭窄形成和雪犁效应等局限性。本研究的目的是探讨在温度监测的光热治疗过程中，使用扩散式 applicator 对食管狭窄进行管状组织体外结构扩张的可行性。猪肝被用作本研究的体外组织样本。使用玻璃管来保持扩散器与组织表面之间的恒定距离，并评估在10瓦1470纳米激光照射后管腔面积的任何变化，以用于潜在的狭窄治疗。三维测角仪测量证实了大致各向同性分布，与来自扩散式 applicator 的2π 上平均角强度的偏差小于10%（即，以任意单位计为0.86 ± 0.09）。30秒的照射将组织温度升高至72.5°C，但由于温度反馈，间质组织温度在70°C时达到饱和（即，稳态误差 = ±0.4°C）。照射时间超过5秒时，面积扩张指数为1.00 ± 0.04，这表明不可逆的组织变性使管腔永久变形为圆形，并确保了与玻璃管等效的管腔面积。对使用扩散式 applicator 的光热治疗应用温度反馈控制器可以调节热变性程度，以可行地治疗管状组织中的食管狭窄。
