Path planning for robot-assisted active flexible needle using improved Rapidly-Exploring Random trees.

In robot-assisted needle-based medical procedures, path planning for a flexible needle is challenging with regard to time consumption and searching robustness for the solution due to the nonholonomic motion of the needle tip and the presence of anatomic obstacles and sensitive organs in the intended needle path. We propose a novel and fast path planning algorithm for a robot-assisted active flexible needle. The algorithm is based on Rapidly-Exploring Random Trees combined with reachability-guided strategy and greedy heuristic strategy.

Novel irradiated axial rotational flap model in the rodent.

Importance: Patients who require extensive surgical resection of head and neck tumors often have a history of treatment with radiation and chemotherapy. Chemoradiation-induced damage to the skin and soft tissues can cause complications following surgical reconstruction.

Objective: To design an easily reproducible rodent rotational skin flap and to evaluate the effects of radiation exposure on flap viability.

Investigation of acoustic radiation force for radio-protecting normal tissues during radiation therapy.

Radiation therapy (radiotherapy) is the medical use of ionizing radiation as part of cancer treatment to erradicate malignant cells. Normal tissue tolerance is currently a major dose-limiting factor. As molecular oxygen plays a critical role in creating the radiation damage, we propose a novel approach, that is, the use of acoustic radiation force (ARF) to suppress the normal tissue oxygenation, for the purpose of protecting the normal tissue and increasing its tolerance during radiotherapy.

Geant4 estimation model of high Z atom concentration for tumor vessel ablation.

In our novel technique of tumor vessels treatment, High Z (HZ) contrast atoms are injected into the blood vessel and the tumor region is irradiated with "narrowband" fluorescence photon (FP) beam tuned to the "resonance energies". Theoretically, this technique guarantees a dose 10(2) - 10(3) higher than that achieved in conventional radiation therapy (RT). Meanwhile, this high dose is confined to a region of tens of micrometers.

Acoustic radiation force and optical spectroscopy for assessing tumor vessel normalization during anti-angiogenic therapy.

Molecular oxygen is the best known mediator of radiation damage during radiation therapy. This paper investigates techniques for enhancing tumor oxygenation by use of anti-angiogenic therapy for better radiosensitivity. A noninvasive monitoring technique, Acoustic radiation force (ARF)-induced optical spectroscopy, was proposed in this paper to track tumor oxygen changes during anti-angiogenic therapy.

Hazard analysis of EUCLIDIAN: an image-guided robotic brachytherapy system.

Robotic assistance can help clinicians to improve the flexibility of needle insertion and accuracy of seed deposition. However, the robotic platform is a safety critical system for its automated operational mode. Thus, it is important to perform Hazard Identification & Safety Insurance Control (HISIC) for securing the safety of a medical robotic system.

'Smart' needle for percutaneous surgery: influential factor investigation.

Precise needle insertion is important for a number of percutaneous interventions. Yet it is difficult to achieve in practice due to target movement and needle deflection. Preliminary design and simulation of 'Smart Needle' are presented in this paper for active needle steering.