Aligarh Muslim University, Jawaharlal Nehru Medical College, Department of Radiotherapy, Aligarh, India.
University of Massachusetts at Boston, Boston, Massachusetts, United States.
J Biomed Opt. 2020 Apr;25(6):1-10. doi: 10.1117/1.JBO.25.6.063813.
India has one of the highest rates of oral cancer incidence in the world, accounting for 30% of reported cancers. In rural areas, a lack of adequate medical infrastructure contributes to unchecked disease progression and dismal mortality rates. Photodynamic therapy (PDT) has emerged as an effective modality with potential for treating early stage disease in resource-limited settings, while photosensitizer fluorescence can be leveraged for treatment guidance.
Our aim was to assess the capability of a simple smartphone-based device for imaging 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence for treatment guidance and monitoring as part of an ongoing clinical study evaluating low-cost technology for ALA-based PDT treatment of early oral cancer.
A total of 29 subjects with <2 cm diameter moderately/well-differentiated microinvasive ( < 5 mm depth) oral squamous cell carcinoma lesions (33 lesions total, mean area ∼1.23 cm2) were administered 60 mg / kg ALA in oral solution and imaged before and after delivery of 100 J / cm2 total light dose to the lesion surface. Smartphone-based fluorescence and white light (WL) images were analyzed and compared with ultrasound (US) imaging of the same lesions.
We present a comparative analysis of pre- and post-treatment fluorescence, WL, and US images of oral lesions. There was no significant difference in the distribution of lesion widths measured by fluorescence and US (mean widths of 14.5 and 15.3 mm, respectively) and linear regression shows good agreement (R2 = 0.91). In general, PpIX fluorescence images obtained prior to therapeutic light delivery are able to resolve lesion margins while dramatic photobleaching (∼42 % ) is visible post-treatment. Segmentation of the photobleached area confirms the boundaries of the irradiated zone.
A simple smartphone-based approach for imaging oral lesions is shown to agree in most cases with US, suggesting that this approach may be a useful tool to aid in PDT treatment guidance and monitoring photobleaching as part of a low-cost platform for intraoral PDT.
印度是世界上口腔癌发病率最高的国家之一，占报告癌症的 30%。在农村地区，缺乏足够的医疗基础设施导致疾病不受控制地发展和死亡率居高不下。光动力疗法（PDT）已成为一种有效的治疗方法，具有在资源有限的环境中治疗早期疾病的潜力，而光敏剂荧光可用于治疗指导。
我们的目的是评估一种简单的基于智能手机的设备对 5-氨基酮戊酸（ALA）诱导的原卟啉 IX（PpIX）荧光成像的能力，作为正在进行的临床研究的一部分，该研究评估了用于治疗早期口腔癌的基于 ALA 的 PDT 的低成本技术。
共 29 名直径 <2cm 的中/高分化微侵袭性（<5mm 深度）口腔鳞状细胞癌病变患者（共 33 个病变，平均面积约为 1.23cm2）接受 60mg/kg/公斤的 ALA 口服溶液，并在病变表面给予 100J/cm2 总光剂量前后进行成像。对基于智能手机的荧光和白光（WL）图像进行分析，并与同一病变的超声（US）图像进行比较。
我们展示了口腔病变的治疗前和治疗后荧光、WL 和 US 图像的对比分析。荧光和 US 测量的病变宽度分布无显著差异（分别为 14.5 和 15.3mm 的平均宽度），线性回归显示良好的一致性（R2=0.91）。一般来说，在给予治疗性光之前获得的 PpIX 荧光图像能够分辨病变边界，而在治疗后可以看到明显的光漂白（~42%）。光漂白区域的分割确认了辐照区域的边界。
一种简单的基于智能手机的口腔病变成像方法与 US 基本一致，表明该方法可能是一种有用的工具，可用于 PDT 治疗指导和监测光漂白，作为用于口腔内 PDT 的低成本平台的一部分。
