Transitioning from interventional radiology: ideas for the inevitable.

BACKGROUND: Interventional Radiology (IR) is a highly rewarding specialty, both for its salutary effects for patients, as will as the satisfaction it provides for the operating radiologists. Nonetheless, arduous work and long hours have led to numerous reports of burnout amongst interventional radiologists (IRs). MATERIALS AND METHODS: Six long-term academic radiologists in leadership positions briefly chronicle their becoming IRs, their type of transitioning from IR, and the pros and cons of those respective transitions. RESULTS: The specific transitions include reduced time in IR, switching to diagnostic radiology, becoming involved in medical school education, ceasing IR leadership, and retirement. Pros and cons of the various transition strategies are highlighted. CONCLUSION: As the taxing work and long hours are so ubiquitous for IRs, and as burnout is so common, transitioning from IR is highly likely eventually for IRs. The varied transition experiences highlighted in this report hopefully will be helpful for current and aspiring IRs.

The clinical day at CARS: philosophy, strategy, and the future.

PURPOSE: For over three decades, the Computer-Assisted Radiology and Surgery (CARS) International Congress and Exhibition has provided a forum for the presentation of innovations in computer applications in radiology, medicine, and surgery. A unique feature of the CARS meetings is the interplay between scientists, engineers, and physicians. Since 2007, a Clinical Day program was introduced to the Congress highlighting the practical applications of new technology within the context of clinical medical and surgical practice. METHODS: The Clinical Day of the CARS Congress allows cross-fertilization of ideas between technologically oriented engineers and clinically oriented physicians; two groups who typically have little interaction. Activities of the Clinical Day include presentations by invited speakers, presentations of Innovative Clinical Investigations, a Panel Discussion and Open Forum, and, most recently, real-time clinical presentations with professionally prepared scholarly videos. Special consideration is given to young researchers and students. There has been an explosion of interest in the Clinical Day with continued and growing interest in Artificial Intelligence, Computer-Assisted Surgery, and new scientific breakthroughs as they become linked to clinical applications. RESULTS: Success of the Clinical Day is emphasized by increased participation and efforts to expand the scope and depth of Clinical Day activities. The Open Forum has proven to be highly effective in identifying important new technologic challenges in medicine and promoting discussion among those whose expertise likely can lead to solutions. CONCLUSIONS: The original goal of the Clinical Day, to provide an effective means to "bridge the gap" between the engineering community and practicing physicians and surgeons, has been realized through the presentation and discussion of real-life, clinical material that utilizes advanced technology. The program has served to inspire young researchers by allowing them to see the end results of their laboratory investigations, thereby gaining a greater appreciation of the importance of their work.

Case report: Atypical polycystic kidney disease.

Atypical or unilateral polycystic kidney disease is a rare entity that is found incidentally and is characterized on imaging as asymmetric or unilateral distribution of cysts confined to the kidneys. We present a case of an incidental finding of atypical polycystic kidney disease in a 72-year-old male. Computed tomography imaging showed asymmetric distribution of cysts only in the kidneys and the patient had no genitourinary symptoms, had normal renal function, and did not have a family history of renal disease. Although considered to be benign, rare cases of progression of atypical polycystic kidney disease to bilateral polycystic kidney disease has been documented in the literature, which portends a worse prognosis. It is important for clinicians to be aware of this entity so that patients can be monitored periodically for progression of disease.

Liquid biopsy and multiparametric analysis in management of liver malignancies: new concepts of the patient stratification and prognostic approach.

BACKGROUND: The annually recorded incidence of primary hepatic carcinomas has significantly increased over the past two decades accounting for over 800 thousand of annual deaths caused by hepatocellular carcinoma (HCC) alone globally. Further, secondary liver malignancies are much more widespread compared to primary hepatic carcinomas: almost all solid malignancies are able to metastasise into the liver. The primary tumours most frequently metastasising to the liver are breast followed by colorectal carcinomas. Given the increased incidence of both primary and metastatic liver cancers, a new, revised approach is needed to advance medical care based on predictive diagnostics, innovative screening programmes, targeted preventive measures, and patient stratification for treatment algorithms tailored to individualised patient profile. ADVANTAGES OF THE APPROACH TAKEN: The current pilot study took advantage of systemic alterations characteristic for liver malignancies, utilising liquid biopsy (blood samples) and specific biomarker patterns detected. Key molecular pathways relevant for pathomechanisms of liver cancers have been considered opening a perspective for both-individualised diagnostics and targeted treatment. Systemic alterations have been analysed prior to the therapy application avoiding molecular biological effects potentially diminishing predictive power of the biomarker-panel proposed. Multi-omics at DNA and protein (both expression and activity) levels has been applied. An established biomarker panel is considered as a powerful tool for individualised patient profiling and improved multi-level diagnostics-both predictive and prognostic ones. RESULTS AND CONCLUSIONS: Biomarker panels have been created for the patient stratification, prediction of a more optimal therapy and prognosis of survival based on the individualised patient profiling. Although there are some limitations of the pilot study performed, the results are encouraging, as it may be possible, through further research along these lines, to find a clinically and cost-effective means of stratifying liver cancer patients for personalised care and therapy. The benefits to the patient and society of accurate treatment stratification cannot be overemphasised.

Validation workflow for a clinical Bayesian network model in multidisciplinary decision making in head and neck oncology treatment.

PURPOSE: Oncological treatment is being increasingly complex, and therefore, decision making in multidisciplinary teams is becoming the key activity in the clinical pathways. The increased complexity is related to the number and variability of possible treatment decisions that may be relevant to a patient. In this paper, we describe validation of a multidisciplinary cancer treatment decision in the clinical domain of head and neck oncology. METHOD: Probabilistic graphical models and corresponding inference algorithms, in the form of Bayesian networks, can support complex decision-making processes by providing a mathematically reproducible and transparent advice. The quality of BN-based advice depends on the quality of the model. Therefore, it is vital to validate the model before it is applied in practice. RESULTS: For an example BN subnetwork of laryngeal cancer with 303 variables, we evaluated 66 patient records. To validate the model on this dataset, a validation workflow was applied in combination with quantitative and qualitative analyses. In the subsequent analyses, we observed four sources of imprecise predictions: incorrect data, incomplete patient data, outvoting relevant observations, and incorrect model. Finally, the four problems were solved by modifying the data and the model. CONCLUSION: The presented validation effort is related to the model complexity. For simpler models, the validation workflow is the same, although it may require fewer validation methods. The validation success is related to the model's well-founded knowledge base. The remaining laryngeal cancer model may disclose additional sources of imprecise predictions.

Patients with hepatic breast cancer metastases demonstrate highly specific profiles of matrix metalloproteinases MMP-2 and MMP-9 after SIRT treatment as compared to other primary and secondary liver tumours.

BACKGROUND: Patients with primary and metastatic liver malignancies represent a highly heterogeneous patient pool characterised by some of the shortest life expectancies amongst oncology patients. Investigation and better understanding of liver malignancies is an emerging field which requires high-quality multidisciplinary research and collaboration. METHODS: A study of 158 patients with primary hepatic carcinomas and secondary liver metastases, altogether 15 cancer types of different origin, who underwent selective internal radiation therapy (SIRT) with Yttrium(90) or transarterial chemoembolisation, was undertaken in an effort to detect distinguishing features with respect to activity profiles of both blood matrix metalloproteinase (MMP-2 and MMP-9). RESULTS: Noteworthy, stratification of all hepatic cancer groups with respect to MMP-2 and MMP-9 activities revealed characteristic patterns specifically in patients with hepatic breast cancer metastases who had undergone SIRT. In contrast to all other groups, these patients demonstrated well-consolidated profiles of both MMPs, reflecting a common feature, namely an immediate and durable increase of their activity after the SIRT treatment. Although the total number of patients in the breast cancer group is relatively small (15 patients), since increased activities of MMP-2 and MMP-9 are well known prognostic factors for poor outcomes of oncologic patients, the significance and clear group-specificity (from 15 ones investigated here) of this previously unanticipated finding requires particular attention and further investigations. Particularly important is to determine, whether this increase of the metalloproteinase activity was provoked by SIRT, as well as whether special selection criteria are required for patients with breast cancer metastases to the liver who are being considered for SIRT. CONCLUSIONS: It is recommended that a more focused, multidisciplinary and large-scaled investigations of the possible adverse effects of SIRT in patients with advanced metastatic disease of breast cancer be undertaken, with an appropriate patients' stratification, set-up of the relevant patient profiles and disease modelling.

Model-guided therapy for hepatocellular carcinoma: a role for information technology in predictive, preventive and personalized medicine.

Predictive, preventive and personalized medicine (PPPM) may have the potential to eventually improve the nature of health care delivery. However, the tools required for a practical and comprehensive form of PPPM that is capable of handling the vast amounts of medical information that is currently available are currently lacking. This article reviews a rationale and method for combining and integrating diagnostic and therapeutic management with information technology (IT), in a manner that supports patients through their continuum of care. It is imperative that any program devised to explore and develop personalized health care delivery must be firmly rooted in clinically confirmed and accepted principles and technologies. Therefore, a use case, relating to hepatocellular carcinoma (HCC), was developed. The approach to the management of medical information we have taken is based on model theory and seeks to implement a form of model-guided therapy (MGT) that can be used as a decision support system in the treatment of patients with HCC. The IT structures to be utilized in MGT include a therapy imaging and model management system (TIMMS) and a digital patient model (DPM). The system that we propose will utilize patient modeling techniques to generate valid DPMs (which factor in age, physiologic condition, disease and co-morbidities, genetics, biomarkers and responses to previous treatments). We may, then, be able to develop a statistically valid methodology, on an individual basis, to predict certain diseases or conditions, to predict certain treatment outcomes, to prevent certain diseases or complications and to develop treatment regimens that are personalized for that particular patient. An IT system for predictive, preventive and personalized medicine (ITS-PM) for HCC is presented to provide a comprehensive system to provide unified access to general medical and patient-specific information for medical researchers and health care providers from different disciplines including hepatologists, gastroenterologists, medical and surgical oncologists, liver transplant teams, interventional radiologists and radiation oncologists. The article concludes with a review providing an outlook and recommendations for the application of MGT to enhance the medical management of HCC through PPPM.

3D++ Visualisation of MEBN Graphs and Screen Representations of Patient Models (PIXIE II).

The aim of this study is to investigate modelling- and visualisation methods and tools for transparent, reproducible and comprehensible information management of patient probabilistic graphical models such as Multi-Entity Bayesian Networks (MEBN). In therapy planning environments, models provide the knowledge base to assist physicians in their decision making process and are typically at the heart of a networked information system. The topic of user interface design (UID) and specifically GUIs needs to be addressed in this context in a very creative manner, if the aim is to make complex models easier for the user to understand and to manage. As a basis for preparing a demonstration to show a proof of concept for the visualisation of MEBNs, the visualization tool called "ANTz" is being proposed here and used as the preferred visualisation tool.

PACS for surgery and interventional radiology: features of a Therapy Imaging and Model Management System (TIMMS).

Appropriate use of information and communication technology (ICT) and mechatronic (MT) systems is viewed by many experts as a means to improve workflow and quality of care in the operating room (OR). This will require a suitable information technology (IT) infrastructure, as well as communication and interface standards, such as specialized extensions of DICOM, to allow data interchange between surgical system components in the OR. A design of such an infrastructure, sometimes referred to as surgical PACS, but better defined as a Therapy Imaging and Model Management System (TIMMS), will be introduced in this article. A TIMMS should support the essential functions that enable and advance image guided therapy, and in the future, a more comprehensive form of patient-model guided therapy. Within this concept, the "image-centric world view" of the classical PACS technology is complemented by an IT "model-centric world view". Such a view is founded in the special patient modelling needs of an increasing number of modern surgical interventions as compared to the imaging intensive working mode of diagnostic radiology, for which PACS was originally conceptualised and developed. The modelling aspects refer to both patient information and workflow modelling. Standards for creating and integrating information about patients, equipment, and procedures are vitally needed when planning for an efficient OR. The DICOM Working Group 24 (WG-24) has been established to develop DICOM objects and services related to image and model guided surgery. To determine these standards, it is important to define step-by-step surgical workflow practices and create interventional workflow models per procedures or per variable cases. As the boundaries between radiation therapy, surgery and interventional radiology are becoming less well-defined, precise patient models will become the greatest common denominator for all therapeutic disciplines. In addition to imaging, the focus of WG-24 is to serve the therapeutic disciplines by enabling modelling technology to be based on standards.

Super-resolution variable-dose imaging in digital radiography: quality and dose reduction with a fluoroscopic flat-panel detector.

PURPOSE: Super-resolution (SR) image processing produces a high-resolution image from a series of low-resolution images. The aim of this study was to evaluate SR-images based on fluoroscopic flat-detector (FD) acquisition at different frame rates. METHODS: Fluoroscopic FD-sequences with 20 frames were obtained with varying pulse frequencies of (1) a line pair resolution phantom; (2) a low-contrast resolution phantom, and (3) a human knee specimen. Super-resolution digital radiographs (SR-Radiographs) were generated from each sequence. Variable-dose images were simulated by constructing SR-Radiographs using 6 and 12 frames from the corresponding fluoroscopic sequence. "Single Shot" and Computed Radiography (CR) images were obtained for comparison based on dynamic range and sharpness of bone detail structures. Patient-derived SR-Radiographic images were constructed to demonstrate clinical examples. RESULTS: The spatial resolution of SR-radiographs obtained at 12.5 frames per second (fps) and 6 fps were comparable with CR and "Single Shot" images, providing ~3.5 line pairs per mm (l p/mm). Similarly, low-contrast resolution of SR-radiographs obtained at 12.5, 6, and 30 fps were equivalent to CR and "Single Shot" images. The human knee specimen SR-radiograph obtained using 12 FD images at 12.5 fps was superior to a CR image in overall image quality, with a dose reduction of 75%. Variable-dose SR-radiographic simulations suggest a dose saving potential of 90-95% when using 6 FD images at 12.5 fps or 6 fps, respectively. CONCLUSIONS: The phantom testing images and simulation results demonstrate that diagnostic quality SR-radiographic images of skeletal extremities can be synthesized using a flat-panel detector system designed primarily for angiography. SR-images obtained with substantially reduced radiation dose are feasible, and this technology may improve digital radiography for pediatric, neonatal radiography, or mammography applications. Further testing is needed to validate super-resolution techniques in other body regions and for different flat-detector systems.

Improved Diagnosis and Navigation for CT Colonography.

The goal of this research project is to develop a fast, accurate, and patient-friendly computer-aided diagnosis (CAD) component of CT colonography, that improves the robustness and accuracy of current colon wall segmentation and achieves earlier colorectal cancer diagnoses through an improved polyp detection method. Many advanced image processing techniques are applied to clearly outline the colon wall in the CT data set of human abdomen, and subtract the colon portion from the entire data set. After the subtraction, the detailed information and the surface curvature information on the colon wall is analyzed. The active contour model is assisted by presegmentation steps including mathematical morphology filtering, edge detection and other image processing techniques.

Scoliosis evaluation by direct digital radiography and computerized post-processing.

With the introduction of direct digital radiography into clinical practice, there are opportunities to provide faster and more reliable ways of performing traditional radiological tasks. A technique was developed for evaluating and measuring scoliosis, which involves the computerized stitching of a radiograph of the thoracic spine with a radiograph of the lumbar spine. A technique is provided for real-time, graphic feedback during the stitching process, as well as during calculation and display of the Cobb angle to ensure accuracy. Initial data indicates an accuracy within 1 to 2 degrees. The time required to stitch the two images and measure the Cobb angle is on the average of 5 minutes per case. Using computerized techniques of image stitching and angle calculation, with real-time graphical feedback, the task of scoliosis evaluation is more accurate, less time consuming, and prone to fewer human errors. The requirement for special film cassettes is also eliminated.