Passively scanned, single-fiber optical coherence tomography probes for gastrointestinal devices

A thin cryobiopsy device compatible with transnasal endoscopy for the gastrointestinal tract

Luminal organ biopsies are critical for disease diagnosis and are obtained using single-bite forceps inserted through the working channel of large endoscopes. Procedures using these endoscopes frequently require patient sedation or anesthesia and may not be feasible for use in pediatric patients. Additionally, forceps-derived biopsies can suffer from difficulty maintaining tissue orientation, crush artifacts, and lack of precise control of biopsy depth. The high cost and risks of anesthesia and sedation have driven the development of smaller endoscopes for unsedated procedures. However, reduced endoscope size limits working-channel dimensions, restricting biopsy forceps to sizes that may yield insufficient or nondiagnostic samples. To address these limitations, we developed an image-guided, depth-controlled, ultrasmall-diameter (1.2-millimeters) cryobiopsy device (μCryoProbe). We optimized the coolant flow profile into the device to enhance tissue freezing, optimizing device-tissue contact time and freezing depth. We tested the device for gastrointestinal biopsy collection in ex vivo preclinical tissues, in an in vivo porcine model, and in sedated human participants. Dimensions and quality of mucosal cryobiopsies from esophagus, stomach, and duodenum were compared with those of forceps-derived biopsies, and it was found that the μCryoProbe device consistently produced high-quality biopsies with optimal tissue orientation and no evidence of crush artifacts. We also demonstrated the ability to capture gastrointestinal biopsies from sedated human participants. By capturing large, well-oriented samples using a small-diameter biopsy tool, this technology has the potential to shift procedures from large to small endoscopes, reducing the need for sedation and improving patient diagnosis through the acquisition of tissue samples with better quality.

The LMIT: Light-mediated minimally-invasive theranostics in oncology

Minimally-invasive diagnosis and therapy have gradually become the trend and research hotspot of current medical applications. The integration of intraoperative diagnosis and treatment is a development important direction for real-time detection, minimally-invasive diagnosis and therapy to reduce mortality and improve the quality of life of patients, so called minimally-invasive theranostics (MIT). Light is an important theranostic tool for the treatment of cancerous tissues. Light-mediated minimally-invasive theranostics (LMIT) is a novel evolutionary technology that integrates diagnosis and therapeutics for the less invasive treatment of diseased tissues. Intelligent theranostics would promote precision surgery based on the optical characterization of cancerous tissues. Furthermore, MIT also requires the assistance of smart medical devices or robots. And, optical multimodality lay a solid foundation for intelligent MIT. In this review, we summarize the important state-of-the-arts of optical MIT or LMIT in oncology. Multimodal optical image-guided intelligent treatment is another focus. Intraoperative imaging and real-time analysis-guided optical treatment are also systemically discussed. Finally, the potential challenges and future perspectives of intelligent optical MIT are discussed.

Study on the application of optical coherence microscopy in Hirschsprung's disease

To explore the clinical application value of optical coherence microscopy (OCM) in Hirschsprung's disease. 109 HSCR patients were recuited in a Chinese hospital from January 2018 to July 2021. All the recruited patients underwent barium enema angiography preoperatively and the resected diseased intestinal tubes were evaluated intraoperatively. The OCM and the histopathological examination were performed successively on the surgical specimens, and the OCM images were compared with the relevant tissue sections to characterize different lesions. 10 non-HSCR fetal colorectal tissues at the same period were retained for OCM, the characteristics of which with and without HSCR under OCM imaging were analyzed. In the OCM images of in vitro tissue, it can be clearly observed that the scattering degree of HSCR narrow segment mucosal is high, glands and crypt structures are reduced or even atrophy, and the scattering degree of submucosal and intermuscular is low; In the dilated segment, the low scattering and high scattering are complex, and the muscle layer is obviously hypertrophy and structural disorder. Compared with the pathological findings, the OCM sensitivity, Kappa value, and AUC area reached 92.66%, 0.63, and 0.91, respectively. OCM can quickly and clearly display the structure of all layers of colorectal tissue, which is highly consistent with the corresponding histopathological examination results and has high sensitivity. which will provide a more reliable basis for OCM diagnosis of early HSCR, targeted biopsy and location of operative treatment, and has a certain potential for clinical application.