We propose a new and complementary approach to image guidance for monitoring medical interventional devices (MID) with human tissue interaction and surgery augmentation by acquiring acoustic emission data from the proximal end of the MID outside the patient to extract dynamical characteristics of the interaction between the distal tip and the tissue touched or penetrated by the MID. We conducted phantom based experiments (n = 955) to show dynamic tool/tissue interaction during tissue needle passage (a) and vessel perforation caused by guide wire artery perforation (b). We use time-varying auto-regressive (TV-AR) modelling to characterize the dynamic changes and time-varying maximal energy pole (TV-MEP) to compute subsequent analysis of MID/tissue interaction characterization patterns. Qualitative and quantitative analysis showed that the TV-AR spectrum and the TV-MEP indicated the time instants of the needle path through different phantom objects (a) and clearly showed a perforation versus other generated artefacts (b). We demonstrated that audio signals acquired from the proximal part of an MID could provide valuable additional information to surgeons during minimally invasive procedures.

Radioguided surgery (RGS) is the use of radiation detection probes and handheld gamma cameras in surgery rooms to identify radioactively labeled lesions inside the body with an aim to improve surgical outcome. In today’s surgery, application of these devices is a well-established practice, which provides surgeons with real-time information to guide them to the site of a lesion. In recent years, there have been several major improvements in the technology and design of gamma probes and handheld gamma cameras, enhancing their applications in surgical practices. Handheld gamma cameras, for example, are now moving from single-modality to dual-modality scanners that add anatomical data to the physiologic data, and with that provide more clinical information of the tissue under study. Also, in the last decade, a radioguided surgical technique based on the Cerenkov radiation was introduced, with more improved sensitivity in identifying radioactively labeled lesions. Additionally, recent advances in hybrid tracers have led to more efficient detection of lesions labeled with these tracers. Besides, it seems that combining medical robotics and augmented reality technology with current radioguided surgical practices potentially will change the delivery and performance of RGS in the near future. The current paper aims to give an overview of the physics of RGS and summarizes recent advances in this field that have a potential to improve the application of radioguided surgical procedures in the management of cancer.

Background: Brachytherapy of thin skin tumors using beta particles can protect underlying sensitive structures such as the bone because of the rapid dose falloff of this type of radiation in tissue. The current work describes a skin brachytherapy applicator, based on beta radiation, that can provide the needed cell‐killing radiation dose matched to the shape of individual skin tumors.Materials and methods: The applicator and its template were fabricated using 3D printing technology. Any clinically approved beta‐emitting isotope in the form of a radioactive gel could theoretically be used in this applicator. Monte Carlo simulations were employed to study the capability of the applicator in conforming dose distribution based on the shape of the tumor. Dose profile in the shallow depth, transverse dose profiles at different depths, and the percent depth dose from this applicator were calculated. The radioisotope of choice for our calculations was Yttrium‐90 (Y‐90).Results: Using the proposed applicator, it is possible to create a desired dose profile matching the tumor surface shape.Conclusion: The short‐range of the beta radiation, together with the dose conforming capability of the applicator, may lead to minimal interactions with the healthy tissue around the skin lesion.

Radiation therapy is a valuable option for treatment of skin cancer. In order to deliver the radiation dose to the superficial skin tumor, an X-ray source, electron beam radiation therapy or a radioisotope is applied. The effectiveness of these procedures is well established in the literature. Findings of some recent studies have indicated that beta particles can be of particular interest in suppressing skin tumor growth. Betaemitting radioisotopes are favorable because of the short penetration depth of their emitted particles. Beta radiation can induce significant damage in superficial skin tumor, and at the same time, result in enhanced protection of the underlying healthy tissues. In this study, we propose the design of a patch that can be used in beta radiation therapy of skin cancer patients. For that, we describe the components of this radioactive patch, as well as a proposal for the subsequent clinical application procedure. A scaffold was used as a substrate for embedding the desired beta-emitting radioisotope, and two layers of hydrogel to provide protection and shielding for the radioactively labelled scaffold. The proposed design could provide a universal platform for all beta-emitting radioisotopes. Depending on the depth of the tumor spread, a suitable beta emitter for that specific tumor can be selected and used. This is of particular and critical importance in cases where the tumor is located directly on top of the bone and for which the depth of penetration of radiation should be limited to only the tumor volume. The proposed design has the mechanical flexibility to adapt to curved body regions so as to allow the use in anatomically challenging areas of the body.

Zusammenfassung: Klinisch-methodisches Problem: Die Bildgebung von Strukturen im Körperinneren erfordert oft den Einsatz ionisierender Strahlung, die grundsätzlich ein Gesundheitsrisiko darstellt. Eine Reduktion der Strahlendosis kann zu verrauschten Bildern führen, die klinisch weniger aussagekräftig sind. Radiologische Standardmethoden: Das Problem tritt bei häufig verwendeten medizinischen Bildgebungsmodalitäten wie Computertomographie (CT), Positronen-Emissions-Tomographie (PET), Einzelphotonen-Emissions-Computertomographie (SPECT), Angiographie, Fluoroskopie und allen Modalitäten auf, bei denen ionisierende Strahlung zur Bildgebung eingesetzt wird. Methodische Innovationen: Die künstliche Intelligenz (KI) könnte die Qualität von Niedrigdosisbildern verbessern und dazu beitragen, die erforderliche Strahlung zu minimieren. Mögliche Anwendungen werden untersucht, und es erfolgt eine kritische Bewertung der Rahmenbedingungen und Verfahren. Bewertung: Die Leistung der KI-Modelle variiert. Hochleistungsmodelle könnten in naher Zukunft im klinischen Umfeld eingesetzt werden. Für eine optimale Leistung und eine breite Einführung dieser Technologie in der medizinischen Bildgebung müssen noch einige Herausforderungen (quantitative Genauigkeit, unzureichende Trainingsdaten etc.) angegangen werden. Praktische Empfehlungen: Um das Potenzial von KI und Deep Learning (DL) in der medizinischen Bildgebung voll auszuschöpfen, müssen Forschung und Entwicklung intensiviert werden. Insbesondere muss die Qualitätskontrolle der KI-Modelle sichergestellt werden, und die Trainings- und Testdaten müssen unkorreliert und qualitätsgesichert sein. Bei hinreichender wissenschaftlicher Absicherung und rigorosem Qualitätsmanagement könnte die KI zu einem sicheren Einsatz von Niedrigdosistechniken in der medizinischen Bildgebung beitragen.