Kim Hyejin, Pyo Hanjae, Kim Hyeonsoo, Kang Hyun Wook
Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea.
Department of Biomedical Engineering, Pukyong National University, Busan 48513, Korea.
Cancers (Basel). 2021 Mar 8;13(5):1146. doi: 10.3390/cancers13051146.
Conventional photothermal therapy (PTT) for cancer typically employs an end-firing flat fiber (Flat) to deliver laser energy, leading to the incomplete treatment of target cells due to a Gaussian-shaped non-uniform beam profile. The purpose of the current study is to evaluate the feasibility of multi-lens arrays (MLA) for enhanced PTT by delivering laser light in a fractional micro-beam pattern. Computational and experimental evaluations compare the photothermal responses of gelatin phantoms and aqueous dye solutions to irradiations with Flat and MLA. In vivo colon cancer models have been developed to validate the therapeutic capacity of MLA-assisted irradiation. MLA yields 1.6-fold wider and 1.9-fold deeper temperature development in the gelatin phantom than Flat, and temperature monitoring identified the optimal treatment condition at an irradiance of 2 W/cm for 180 s. In vivo tests showed that the MLA group was accompanied by complete tumor eradication, whereas the Flat group yielded incomplete removal and significant tumor regrowth 14 days after PTT. The proposed MLA-assisted PTT spatially augments photothermal effects with the fractional micro-beams on the tumor and helps achieve complete tumor removal without recurrence. Further investigations are expected to optimize treatment conditions with various wavelengths and photosensitizers to warrant treatment efficacy and safety for clinical translation.
传统的癌症光热疗法（PTT）通常采用端射扁平光纤（Flat）来传递激光能量，由于高斯形状的非均匀光束轮廓，导致靶细胞治疗不完全。本研究的目的是评估多透镜阵列（MLA）通过以分数微束模式传递激光来增强PTT的可行性。计算和实验评估比较了明胶模型和水性染料溶液对Flat和MLA照射的光热响应。已建立体内结肠癌模型以验证MLA辅助照射的治疗能力。与Flat相比，MLA在明胶模型中产生的温度升高范围宽1.6倍，深度深1.9倍，温度监测确定在2 W/cm的辐照度下照射180 s为最佳治疗条件。体内试验表明，MLA组实现了肿瘤完全根除，而Flat组在PTT后14天肿瘤切除不完全且出现明显的肿瘤复发。所提出的MLA辅助PTT通过肿瘤上的分数微束在空间上增强光热效应，并有助于实现肿瘤完全切除且无复发。预计进一步的研究将优化使用各种波长和光敏剂的治疗条件，以确保临床转化的治疗效果和安全性。
