Radiation Protection and Occupational Exposure on 68Ga-PSMA-11-Based Cerenkov Luminescence Imaging Procedures in Robot-Assisted Prostatectomy

Innovations in dedicated PET instrumentation: from the operating room to specimen imaging

This review casts a spotlight on intraoperative positron emission tomography (PET) scanners and the distinctive challenges they confront. Specifically, these systems contend with the necessity of partial coverage geometry, essential for ensuring adequate access to the patient. This inherently leans them towards limited-angle PET imaging, bringing along its array of reconstruction and geometrical sensitivity challenges. Compounding this, the need for real-time imaging in navigation systems mandates rapid acquisition and reconstruction times. For these systems, the emphasis is on dependable PET image reconstruction (without significant artefacts) while rapid processing takes precedence over the spatial resolution of the system. In contrast, specimen PET imagers are unburdened by the geometrical sensitivity challenges, thanks to their ability to leverage full coverage PET imaging geometries. For these devices, the focus shifts: high spatial resolution imaging takes precedence over rapid image reconstruction. This review concurrently probes into the technical complexities of both intraoperative and specimen PET imaging, shedding light on their recent designs, inherent challenges, and technological advancements.

Current clinical applications of Cerenkov luminescence for intraoperative molecular imaging

BACKGROUND

Cerenkov luminescence imaging (CLI) is a new emerging technology that can be used for optical imaging of approved radiotracers, both in a preclinical, and even more recently, in a clinical context with rapid imaging times, low costs, and detection in real-time (Grootendorst et al. Clin Transl Imaging 4(5):353-66, 2016); Wang et al. Photonics 9(6):390, 2022). This brief review provides an overview of clinical applications of CLI with a focus on intraoperative margin assessment (IMA) to address shortcomings and provide insight for future work in this application.

METHODS

A literature review was performed using PubMed using the search words Cerenkov luminescence imaging (CLI), intraoperative margin assessment (IMA), and image-guided surgery. Articles were selected based on title, abstract, content, and application.

RESULTS

Original research was summarized to examine advantages and limitations of CLI compared to other modalities for IMA. The characteristics of Cerenkov luminescence (CL) are defined, and results from relevant clinical trials are discussed. Prospects of ongoing clinical trials are reviewed, along with technological advancements related to CLI.

CONCLUSION

CLI is a proven method for molecular imaging and shows feasibility for determining intraoperative margins if future work involves establishing quantitative approaches for attenuation and scattering, depth analysis, and radiation safety for CLI at a larger scale.

Surgical radioguidance with beta-emitting radionuclides; challenges and possibilities: A position paper by the EANM

Radioguidance that makes use of β-emitting radionuclides is gaining in popularity and could have potential to strengthen the range of existing radioguidance techniques. While there is a strong tendency to develop new PET radiotracers, due to favorable imaging characteristics and the success of theranostics research, there are practical challenges that need to be overcome when considering use of β-emitters for surgical radioguidance. In this position paper, the EANM identifies the possibilities and challenges that relate to the successful implementation of β-emitters in surgical guidance, covering aspects related to instrumentation, radiation protection, and modes of implementation.

Modified low-dose second window indocyanine green technique improves near-infrared fluorescence image-guided dermatofibrosarcoma protuberans resection: A randomized control trial

Objective

Conventional second window indocyanine green (SWIG) technique has been widely attempted in near-infrared fluorescence (NIRF) imaging for intraoperative navigation of tumor radical resection. Nevertheless, the overuse of indocyanine green (ICG) led to an increased risk of drug lethal allergy and high medical cost. This prospective study was to explore clinical application of modified low-dose SWIG technique in guiding dermatofibrosarcoma protuberans (DFSPs) radical resection.

Method

Patients with DFSPs were randomly assigned to control and experimental group. The ICG was injected intravenously 24 h before surgery, at a dose of 3.5 mg/kg in the control group and 25 mg/patient in the experiment group, respectively. Intraoperative NIRF imaging included serial views of gross tumor, tumor bed and cross-sectional specimen.

Results

Although NIRF imaging of gross tumor and tumor bed in the experimental group demonstrated similar sensitivity and negative predictive value, the specificity and positive predictive value were obviously higher compared to control group. The tumor-to-background ratios of cross-sectional specimens in the experimental group was significantly higher than in the control group (P = 0.000). Data in both groups displayed that there was a positive correlation of tumor size in cross-sections between integrated histopathologic photomicrographs and NIRF imaging of specimen views (P = 0.000). NIRF imaging of cross-sectional specimens had a significant decrease in time cost, and an increase in the ability of examining more surgical margins (P = 0.000).

Conclusion

This is the first study to demonstrate that a low-dose SWIG technique could improve the accuracy of near-infrared fluorescence image-guided dermatofibrosarcoma protuberans resection.

Clinical Trial Registration: ChiCTR2100050174; date of registration: August 18, 2021 followed by “retrospectively registered”