Indocyanine green fluorescence image processing techniques for breast cancer macroscopic demarcation

Photonics-powered augmented reality skin electronics for proactive healthcare: multifaceted opportunities

Rapid technological advancements have created opportunities for new solutions in various industries, including healthcare. One exciting new direction in this field of innovation is the combination of skin-based technologies and augmented reality (AR). These dermatological devices allow for the continuous and non-invasive measurement of vital signs and biomarkers, enabling the real-time diagnosis of anomalies, which have applications in telemedicine, oncology, dermatology, and early diagnostics. Despite its many potential benefits, there is a substantial information vacuum regarding using flexible photonics in conjunction with augmented reality for medical purposes. This review explores the current state of dermal augmented reality and flexible optics in skin-conforming sensing platforms by examining the obstacles faced thus far, including technical hurdles, demanding clinical validation standards, and problems with user acceptance. Our main areas of interest are skills, chiroptical properties, and health platform applications, such as optogenetic pixels, spectroscopic imagers, and optical biosensors. My skin-enhanced spherical dichroism and powerful spherically polarized light enable thorough physical inspection with these augmented reality devices: diabetic tracking, skin cancer diagnosis, and cardiovascular illness: preventative medicine, namely blood pressure screening. We demonstrate how to accomplish early prevention using case studies and emergency detection. Finally, it addresses real-world obstacles that hinder fully realizing these materials' extraordinary potential in advancing proactive and preventative personalized medicine, including technical constraints, clinical validation gaps, and barriers to widespread adoption.

Fluorescence guided surgery imaging systems for breast cancer identification: a systematic review

Significance

Breast-conserving surgery (BCS) is limited by high rates of positive margins and re-operative interventions. Fluorescence-guided surgery seeks to detect the entire lesion in real time, thus guiding the surgeons to remove all the tumor at the index procedure.

Aim

Our aim was to identify the optimal combination of a camera system and fluorophore for fluorescence-guided BCS.

Approach

A systematic review of medical databases using the terms "fluorescence," "breast cancer," "surgery," and "fluorescence imaging" was performed. Cameras were compared using the ratio between the fluorescent signal from the tumor compared to background fluorescence, as well as diagnostic accuracy measures, such as sensitivity, specificity, and positive predictive value.

Results

Twenty-one studies identified 14 camera systems using nine different fluorophores. Twelve cameras worked in the infrared spectrum. Ten studies reported on the difference in strength of the fluorescence signal between cancer and normal tissue, with results ranging from 1.72 to 4.7. In addition, nine studies reported on whether any tumor remained in the resection cavity (5.4% to 32.5%). To date, only three studies used the fluorescent signal for guidance during real BCS. Diagnostic accuracy ranged from 63% to 98% sensitivity, 32% to 97% specificity, and 75% to 100% positive predictive value.

Conclusion

In this systematic review, all the studies reported a clinically significant difference in signal between the tumor and normal tissue using various camera/fluorophore combinations. However, given the heterogeneity in protocols, including camera setup, fluorophore studied, data acquisition, and reporting structure, it was impossible to determine the optimal camera and fluorophore combination for use in BCS. It would be beneficial to develop a standardized reporting structure using similar metrics to provide necessary data for a comparison between camera systems.

Deciphering the Role of H-Ferritin Nanocages in Improving Tumor-Targeted Delivery of Indocyanine Green: Combined Analysis of Murine Tissue Homogenates with UHPLC-MS/MS and Fluorescence

We investigated the relevance of encapsulation in H-ferritin nanocages (HFn) in determining an improved tumor-targeted delivery of indocyanine green (ICG). Since from previous experiments, the administration of HFn loaded with ICG (HFn-ICG) resulted in an increased fluorescence signal of ICG, our aim was to uncover if the nanoformulation could have a major role in driving a specific targeting of the dye to the tumor or rather a protective action on ICG's fluorescence. Here, we took advantage of a combined analysis involving ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) on murine tissue homogenates matched with fluorescence intensities analysis detected by ex vivo optical imaging. The quantification of ICG content performed on different organs over time combined with the fluorescent signal detection confirmed the superior delivery of ICG thanks to the nanoformulation. Our results showed that HFn-ICG drives a real accumulation at the tumor instead of only having a role in the preservation of ICG's fluorescence, further supporting its use as a delivery system of ICG for fluorescence-guided surgery applications in oncology.

Design of a Miniature Observation Robot for Light Emitting Diode Irradiation and Indocyanine Green Fluorescence-emission Guided Lymph Node Monitoring in Operating Rooms

MOTIVATION

Typical surgical microscopes used for fluorescence-based lymph node detection experience limitations such as weight and restricted adjustability of the integrated light emitting diode (LED) and camera. This restricts the capture of detailed images of specific regions within the lesion.

RESEARCH GOAL

This study proposes a miniature observation robot design that offers adjustable working distance (WD) and rotational radius, along with zoom-in/zoom-out functionality.

METHODS

A five-degree-of-freedom manipulator was designed, with the end effector incorporating an LED and concave lens to widen the beam width for comprehensive lesion illumination. Additionally, a long-pass filter was integrated into the camera system to enhance image resolution.

EXPERIMENTAL RESULTS

Experiments were conducted using a fluorescence-expressing phantom to evaluate the performance of the robot. Results demonstrated a captured image resolution of 9600 × 3240 pixels and a zoom-in/zoom-out capacity of up to 3.68 times.

CONCLUSION

The proposed robot design is cost-effective and highly adjustable, enabling suitability for rapid and accurate detection of fresh lymph nodes during surgeries. The robot's capability to detect small lesions (<1 cm), as validated by phantom tests, holds promise for the detection of minute lymph nodes.

Indocyanine Green Fluorescence Imaging in the Surgical Management of Skin Squamous Cell Carcinoma

Introduction

Indocyanine green (ICG) fluorescence imaging has been used in the resection surgery and sentinel lymph node biopsy of many tumors. The aim of the present study is to verify the feasibility and effectiveness of ICG fluorescence imaging used for guiding the biopsy and resection of skin squamous cell carcinoma (SSCC).

Methods

Sixty patients were enrolled, including 18 patients of suspected SSCC and 42 patients of diagnosed SSCC on admission. The ICG fluorescence imaging-guided skin biopsy was performed preoperatively in the 18 cases of suspected SSCC. Fifty-three patients underwent ICG fluorescence imaging-guided radical excision.

Results

The results showed that 138 skin tissue samples in 60 patients with preoperative or intraoperative ICG fluorescence imaging-guide biopsy were collected. For a total number of 138 biopsies, 122 specimens were squamous cell carcinoma, and the accuracy rate was 88.4%, which was significantly higher than that of the group without preoperative ICG fluorescence imaging (41/62, 66.1%, P < 0.05). Fifty-three patients underwent surgery guided with ICG fluorescence imaging. Residual fluorescent signals in 24 patients were intraoperatively found and the excision was then expanded until the signals disappeared. Follow-up to November 2022, 12 patients died, of which 5 cases died from the tumor recurrence, and the others died due to advanced ages or other reasons. The recurrence rate was 9.4%, which was not significantly different from that of the group received routine radical resection (4/35, 11.4%, P > 0.05). Moreover, sentinel lymph nodes were successfully detected under ICG fluorescence imaging in the 4 patients with suspected lymph node metastases, and the location of lymph nodes can be precisely identified.

Conclusion

ICG fluorescence imaging technique can guide the pathology biopsy to improve the accuracy of pathological examination, and help to identify the boundaries of tumor tissues and sentinel lymph nodes to resect tumor radically during operation.

Contrast-Enhanced Multispectral Optoacoustic Tomography for Functional Assessment of the Gastrointestinal Tract

Real-time imaging and functional assessment of the intestinal tract and its transit pose a significant challenge to conventional clinical diagnostic methods. Multispectral optoacoustic tomography (MSOT), a molecular-sensitive imaging technology, offers the potential to visualize endogenous and exogenous chromophores in deep tissue. Herein, a novel approach using the orally administered clinical-approved fluorescent dye indocyanine green (ICG) for bedside, non-ionizing evaluation of gastrointestinal passage is presented. The authors are able to show the detectability and stability of ICG in phantom experiments. Furthermore, ten healthy subjects underwent MSOT imaging at multiple time points over eight hours after ingestion of a standardized meal with and without ICG. ICG signals can be visualized and quantified in different intestinal segments, while its excretion is confirmed by fluorescent imaging of stool samples. These findings indicate that contrast-enhanced MSOT (CE-MSOT) provides a translatable real-time imaging approach for functional assessment of the gastrointestinal tract.

Recent advances in optical imaging through deep tissue: imaging probes and techniques

Optical imaging has been essential for scientific observations to date, however its biomedical applications has been restricted due to its poor penetration through tissues. In living tissue, signal attenuation and limited imaging depth caused by the wave distortion occur because of scattering and absorption of light by various molecules including hemoglobin, pigments, and water. To overcome this, methodologies have been proposed in the various fields, which can be mainly categorized into two stategies: developing new imaging probes and optical techniques. For example, imaging probes with long wavelength like NIR-II region are advantageous in tissue penetration. Bioluminescence and chemiluminescence can generate light without excitation, minimizing background signals. Afterglow imaging also has high a signal-to-background ratio because excitation light is off during imaging. Methodologies of adaptive optics (AO) and studies of complex media have been established and have produced various techniques such as direct wavefront sensing to rapidly measure and correct the wave distortion and indirect wavefront sensing involving modal and zonal methods to correct complex aberrations. Matrix-based approaches have been used to correct the high-order optical modes by numerical post-processing without any hardware feedback. These newly developed imaging probes and optical techniques enable successful optical imaging through deep tissue. In this review, we discuss recent advances for multi-scale optical imaging within deep tissue, which can provide reseachers multi-disciplinary understanding and broad perspectives in diverse fields including biophotonics for the purpose of translational medicine and convergence science.

Overview of Biofluids and Flow Sensing Techniques Applied in Clinical Practice

This review summarizes the current knowledge on biofluids and the main flow sensing techniques applied in healthcare today. Since the very beginning of the history of medicine, one of the most important assets for evaluating various human diseases has been the analysis of the conditions of the biofluids within the human body. Hence, extensive research on sensors intended to evaluate the flow of many of these fluids in different tissues and organs has been published and, indeed, continues to be published very frequently. The purpose of this review is to provide researchers interested in venturing into biofluid flow sensing with a concise description of the physiological characteristics of the most important body fluids that are likely to be altered by diverse medical conditions. Similarly, a reported compilation of well-established sensors and techniques currently applied in healthcare regarding flow sensing is aimed at serving as a starting point for understanding the theoretical principles involved in the existing methodologies, allowing researchers to determine the most suitable approach to adopt according to their own objectives in this broad field.