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Open-source software packages have been extensively used in the past three decades in medical imaging and diagnostics, aiming to study the feasibility of the application ex vivo. Unfortunately, most of the existing open-source tools require some software engineering background to install the prerequisite libraries, choose a suitable computational platform, and combine several software tools to address different applications.To facilitate the use of open-source software in medical applications, enabling computational studies of treatment outcomes prior to the complex in-vivo setting.FullMonteWeb, an open-source, user-friendly web-based software with a graphical user interface for interstitial photodynamic therapy (iPDT) modeling, visualization, and optimization, is introduced. The software can perform Monte Carlo simulations of light propagation in biological tissues, along with iPDT plan optimization. FullMonteWeb installs and runs the required software and libraries on Amazon Web Services (AWS), allowing scalable computing without complex set up.FullMonteWeb allows simulation of large and small problems on the most appropriate compute hardware, enabling cost improvements of 10 × versus always running on a single platform. Case studies in optical property estimation and diffuser placement optimization highlight FullMonteWeb's versatility.The FullMonte open source suite enables easier and more cost-effective in-silico studies for iPDT.

Background Isolated lung metastases in sarcoma and colorectal cancer patients are inadequately treated with current standard therapies. In Vivo Lung Perfusion, a novel platform, could overcome limitations to photodynamic therapy treatment volumes by using low cellular perfusate, removing blood, theoretically allowing greater light penetration. To develop personalized photodynamic therapy protocols requires in silico light propagation simulations based on optical properties and maximal permissible photodynamic threshold dose of lung tissue. This study presents quantification of optical properties for two perfusates and the photodynamic threshold for 5-ALA and Chlorin e6. Methods Porcine and human lungs were placed on Ex Vivo Lung Perfusion, and perfused with acellular solution or blood. Isotropic diffusers were placed within bronchi and on lung surface for light transmission measurements, from which absorption and light scattering properties were calculated at multiple wavelengths. Separately, pigs were injected with 5-ALA or Chlorin e6, and lung tissue was irradiated at increasing doses. Resultant lesion sizes were measured by CT and histology to quantify the photodynamic threshold. Results Low cellular perfusate reduced the tissue absorption coefficient significantly, increasing penetration depth of light by 3.3 mm and treatment volumes 3-fold. The photodynamic threshold for lung exposed to 5-ALA was consistent with other malignancies. Chlorin e6 levels were undetectable in lung tissue and did not demonstrate photodynamic-induced necrosis. Conclusions Light penetration with low cellular perfusate is significantly greater and could enable treatments for diffuse disease. This data aids photodynamic treatment planning and will guide clinical translation of photodynamic therapy protocols in the lung, especially during lung perfusion.

This study presents numerical simulations of UVC light propagation through seven different filtered face respirators (FFR) to determine their suitability for UV germicidal inactivation (UVGI). UV propagation was modelled using the FullMonte program for two external light illuminations. The optical properties of the dominant three layers were determined using the inverse adding doubling method.The resulting fluence rate volume histograms and the lowest fluence rate recorded in the modelled volume, sometimes in the nW cm-2, provide feedback on a respirator’s suitability for UVGI and the required exposure time for a given light source. While UVGI can present an economical approach to extend an FFR’s useable lifetime, it requires careful optimization of the illumination setup and selection of appropriate respirators.Abstract Figure

Significance: Photodynamic therapy (PDT) could become a treatment option for nonmuscle invasive bladder cancer when the current high morbidity rate associated with red light PDT and variable PDT dose can be overcome through a combination of intravesical instillation of the photosensitizer and the use of green light creating a steep PDT dose gradient. Aim: To determine how a high PDT selectivity can be maintained throughout the bladder wall considering other efficacy determining parameters, in particular, the average optical properties of the mucosal layer governing the fluence rate multiplication factor, as well as the bladder shape and the position of the emitter in relationship to the bladder wall. Approach: We present three irradiance monitoring systems and evaluate their ability to enable selective bladder PDT considering previously determined photodynamic threshold values for the bladder cancer, mucosa and urothelium in a preclinical model, and the photosensitizer’s specific uptake ratio. Monte Carlo-based light propagation simulations performed for six human bladders at the time of therapy for a range of tissue optical properties. The performance of one irradiance sensing device in a clinical phase 1B trial is presented to underline the impact of irradiance monitoring, and it is compared to the Monte Carlo-derived dose surface histogram. Results: Monte Carlo simulations showed that irradiance monitoring systems need to comprise at least three sensors. Light scattering inside the bladder void needs to be minimized to prevent increased heterogeneity of the irradiance. The dose surface histograms vary significantly depending on the bladder shape and bladder volume but are less dependent on tissue optical properties. Conclusions: We demonstrate the need for adequate irradiance monitoring independent of a photosensitizer’s specific uptake ratio.

While the prevalence of central bronchial tumours is declining, that of peripheral lung tumours is increasing. Peripheral lung tumours present either as individual index lesion or as field cancerization, requiring for the former targeting of particular confined volumes of lung tissue versus a therapy for an entire lung or particular lobes thereof. Using FullMonte, a Monte Carlo code; the ability to achieve a tumour selective PDT by transbronchial light source placement was simulated for 525, 665 and 808 nm wavelength. Simulations were executed utilizing in silica models with up to 10 generations of the bronchial tree, tissue photosensitizer concentrations taken from literature or measure in preclinical model systems and tissue optical properties measured with alive ex vivo pig and human lungs perfused with either blood or a transparent low cellular (STEEN) fluid. The measured effective attenuation coefficients [cm-1] at the three wavelengths for ventilated lungs with either blood 1.26±1.07, 1.93±0.534, 1.09±0.93 or STEEN fluid 1.01±0.873, 0.901±0.318, 0.641±0.31 used as perfusate. When modelling the PDT dose distribution in the lung’s the bronchial air ducts up to the eight generations perturb the fluence considerably. In all simulations, a dose sufficient to cause necrosis in 98% of the target volume placement of 3 source fibres albeit with various extent of normal lung tumour damage. Full coverage of an entire lung lobe with only three source fibres placed does not provide for effective coverage of the diffuse disease unless a very high selective uptake of the photosensitizer in malignant tissues can be achieved.

Recurrent Non-Muscle Invasive Bladder Cancer (NMIBC) is a diffuse disease, and patients have failed standard BCG therapy face prophylactic cystectomy. PDT fell out of favour due to its variable outcome, and high morbidity. To overcome PDT associate toxicity to the bladder’s muscle layer, the use of shorter wavelength and instillation of the photosensitizer were suggested. While either approach was shown to improve the outcome in animal models they have not previously combined in human studies. Additionally, the effects of highly variable tissue optical properties of the bladder and its shape have not been studied. Here, we present surface dose histograms derived from light propagation simulation in 6 human bladders using CT images for anatomical detail and the FullMonte software package. The ability of a single light sensor versus 3 or 12 light sensors to measure the average irradiance on the bladder surface was evaluated as a function of the bladder wall’s tissue optical properties. Results show that the irradiance in non-spherical bladders can vary over an order of magnitude, but the irradiance histograms are affected little by displacement of the emitter inside the bladder void. As the surface area monitored by a single sensor depends strongly on the bladder shape, the responsivity of a single sensor to the average bladder irradiance can vary equally. Twelve light sensors monitor the entire bladder surface almost complete and hence their average responsivity is constant to the average irradiance on the bladder largely independent of shape. The dependency of the sensor’s response on the tissue optical properties is also lower.

The utility to perform treatment planning for transbronchial light delivery is investigated using Monte Carlo simulations. Optical properties of pig and human lungs were determined, and dose volume histograms determined. These dose volume histograms indicate for example the minimum photosensitizer specific uptake ratio required to achieve selective tumour destruction.

Determining the light propagation in heterogeneous media is a challenging task which can only be approximated by solving the Boltzmann transport equation via diffusion theory. However, diffusion theory becomes very inaccurate at interfaces, boundaries, sources, and sinks, which are present in heterogeneous media. Monte Carlo methods are able to converge to the correct solution by simulating a sufficiently high number of photons, at the cost of increased runtime. Therefore, it is important to optimize the Monte Carlo simulator, thereby allowing more photons to be simulated and a more accurate solution within a given runtime. FullMonte is a full-featured simulator that uses processor-optimized operations to achieve the highest performance of any 3D tetrahedral Monte Carlo light propagation software to date. This paper presents two medical use cases which benefit from FullMonte, highlights new features and explains the optimizations that lead to its high performance.

Spinal bone metastases often present as a diffuse combination of osteolytic and osteoblastic disease. Photodynamic therapy (PDT) is a minimally invasive therapy that has been shown to locally ablate cancer cells within the bony spine. To optimize patient-specific treatment protocols and ensure safety of critical neural structures, the responsivities of the heterogenous tissues to PDT must be known. This work derives a PDT threshold value for the spinal cord using a benzoporphyrin derivative monoacid (BPD-MA) photosensitizer.

Median survival for Glioblastoma patients remains at around 15 months after surgery, radiation, and chemotherapy but varies widely between surgeons and centres. Interstitial Photodynamic Therapy (iPDT) mediated by ALA induced PpIX or other photosensitizers is investigated at various clinics. To enable iPDT treatment planning, photosensitizer transport characteristics needs to be known in order to optimize photoactivation. A method using contrast enhanced, functional magnetic resonance imaging, compartment modelling, spatial frequency domain imaging (SFDI) and inductively coupled plasma mass spectrometry (ICP-MS) is proposed to predict and validate the localization characteristics of two photosensitizers in murine Glioblastoma models.

Significance: Photodynamic therapy (PDT) could become a treatment option for nonmuscle invasive bladder cancer when the current high morbidity rate associated with red light PDT and variable PDT dose can be overcome through a combination of intravesical instillation of the photosensitizer and the use of green light creating a steep PDT dose gradient. Aim: To determine how a high PDT selectivity can be maintained throughout the bladder wall considering other efficacy determining parameters, in particular, the average optical properties of the mucosal layer governing the fluence rate multiplication factor, as well as the bladder shape and the position of the emitter in relationship to the bladder wall. Approach: We present three irradiance monitoring systems and evaluate their ability to enable selective bladder PDT considering previously determined photodynamic threshold values for the bladder cancer, mucosa and urothelium in a preclinical model, and the photosensitizer’s specific uptake ratio. Monte Carlo-based light propagation simulations performed for six human bladders at the time of therapy for a range of tissue optical properties. The performance of one irradiance sensing device in a clinical phase 1B trial is presented to underline the impact of irradiance monitoring, and it is compared to the Monte Carlo-derived dose surface histogram. Results: Monte Carlo simulations showed that irradiance monitoring systems need to comprise at least three sensors. Light scattering inside the bladder void needs to be minimized to prevent increased heterogeneity of the irradiance. The dose surface histograms vary significantly depending on the bladder shape and bladder volume but are less dependent on tissue optical properties. Conclusions: We demonstrate the need for adequate irradiance monitoring independent of a photosensitizer’s specific uptake ratio.

The EU-funded project RADIO brings forward a new healthcare paradigm according to which a mobile robotic platform can act as an assistant to an elderly person in his/her domestic environment. The main goal of the robot is to detect ADL (Activities of Daily Life) related to basic self-care tasks, such as sleeping and taking medications, as well as instrumental ADL related to housework. ADL detection is based on visual, depth, and audio signal analysis as well as their fusion. However, robot assistance in everyday living suffers from limited autonomy dictated by the robot battery, e.g., the robot has to constantly know where the person is and to be able to move if the person moves to a new location or another room. In this chapter, we present the line of research followed in the RADIO project in order to reduce the usage of the power-hungry processing components and, consequently, the need for revisiting, to the extent possible, the robot charging station. Our approach is based on building specialized, hardware acceleration units on a Zynq-based FPGA of Xilinx. Moreover, a hardware–software partitioning approach is performed base on the HLS (high-level synthesis) paradigm. In this way, the robot will be able to perform computation-intensive tasks in a power-efficient manner.

In the context of RADIO project, seamless integration of Robotic platform, heterogenous home automation technologies and diverse back infrastructures comprised an integral challenge to the success of the overall endeavor. This observation gave the involved partners the chance to explore difference technological and design approaches in order to yield the optimum implementation. At the same time, it highlighted the need to follow a structured, multifaceted approach in order to tackle efficiently all requirements. Based on this process, the main objective of this chapter is to present the most important lessons learned as well as emphasize on the key aspects where enhancements and novel contributions were achieved in RADIO. Therefore, in the first section, after the conceptual communication architecture defined in RADIO is presented, critical communication requirements of the RADIO platform are identified focusing on local area ultra-low power communication technologies deployed in the home premises as well as efficient cloud infrastructure utilized. Then the second section highlights the actual state-of-the-art communication technologies explored, deployed, and integrated in the context of RADIO platform emphasizing on bridging and coexistence critical challenges encountered and addressed. Focusing on the integration problem the RADIO Gateway entity represented one of the most important cornerstones for the overall RADIO platform performance effectively comprising a highly complex compound entity, adequately analyzed in Sect. 5.3. Then in Sect. 5.4 important research activities based on BLE communication technology are presented, enabling, on one hand, accurate indoor localization and, on the other hand, extended coverage area capabilities through multi-hop communication. Finally, Sect. 5.5 presents all development and integration effort devoted by RADIO partners to the backend infrastructure. Although, many times, not highlighted adequately, backend infrastructure is a critical part of the overall architecture since it effectively comprises the bases for key services such as, data storage, data processing, data representation, network management, network configuration, etc.

This paper presents an acceleration method for an image processing algorithm from the RADIO EU project. The algorithm was profiled and the compute intensive tasks were then mapped on programmable hardware. The accelerator design was done with Vivado HLS. The accelerator implements the image processing algorithm as OpenCL kernel and optimizes its performance based on the analysis of the generated hardware. However, the OpenCL code does not reach acceptable speedups when implemented as is. For better performance, several optimizations steps have to be exceuted. The results show that software generated as hardware on programmable hardware can reach a speedup of up to 1.32. For this, further knowledge of the underlying hardware is required.

In industrial robotics, most robotic arms are designed to enable an analytic solution for motion control tasks. This design restricts the movement flexibility of robotic arms. Numerical methods are able to fulfill the motion control tasks without requiring design restrictions on the robotic arm. However, they require more processing time to acquire a solution. In this paper, we analyze and accelerate the inverse Jacobian, pseudo inverse Jacobian, gradient descent, and the Newton method through an FPGA design using high-level synthesis (HLS). The final hardware implementations were designed in order to provide a good balance between high performance and acceptable FPGA resource utilization.

International audience; The FlexTiles Platform has been developed within a Seventh Framework Programme project which is co-funded by the European Union with ten participants of five countries. It aims to create a self-adaptive heterogeneous many-core architecture which is able to dynamically manage load balancing, power consumption and faulty modules. Its focus is to make the architecture efficient and to keep programming effort low. Therefore, the concept contains a dedicated automated tool-flow for creating both the hardware and the software, a simulation platform that can execute the same binaries as the FPGA prototype and a virtualization layer to manage the final heterogeneous many-core architecture for run-time adaptability. With this approach software development productivity can be increased and thus, the time-to-market and development costs can be decreased. In this paper we present the FlexTiles Development Platform with a many-core architecture demonstration. The steps to implement, validate and integrate two use-cases are discussed.

Demographic and epidemiologic transitions have brought forward a new health care paradigm with the presence of both growing elderly population and chronic diseases. Recent technological advances can support elderly people in their domestic environment assuming that several ethical and clinical requirements can be met. This paper presents an architecture that is able to meet these requirements and investigates the technical challenges introduced by our approach.