Typical Clinical Scenarios Research Articles

A phantom for verification of dwell position and time of a high dose rate brachytherapy source

Accuracy of dwell position and reproducibility of dwell time are critical in high dose rate (HDR) brachytherapy. A phantom was designed to verify dwell position and dwell time reproducibility for an Ir-192 HDR stepping source using Computed Radiography (CR). The central part of the phantom, incorporating thin alternating strips of lead and acrylic, was used to measure dwell positions. The outer part of the phantom features recesses containing different absorber materials (lead, aluminium, acrylic and polystyrene foam), and was used for determining reproducibility of dwell times. Dwell position errors of < 1 mm were easily detectable using the phantom. The effect of bending a transfer tube was studied with this phantom and no change of clinical significance was observed when varying the curvature of the transfer tube in typical clinical scenarios. Changes of dwell time as low as 0.1 s, the minimum dwell time of the treatment unit, could be detected by choosing dwell times over the four materials that produce identical exposure at the CR detector.

Treatment algorithm for moderate to severe ulcerative colitis

The care for a patient with ulcerative colitis (UC) remains challenging despite the fact that morbidity and mortality rates have been considerably reduced during the last 30 years. The traditional management with intravenous corticosteroids was modified by the introduction of ciclosporin and infliximab. In this review, we focus on the treatment of patients with moderate to severe UC. Four typical clinical scenarios are defined and discussed in detail. The treatment recommendations are based on current literature, published guidelines and reviews, and were discussed at a consensus meeting of Swiss experts in the field. Comprehensive treatment algorithms were developed, aimed for daily clinical practice.

The ELDER Project: Educational Model and Three-Year Outcomes of a Community-Based Geriatric Education Initiative

The purpose of the ELDER (Expanded Learning and Dedication to Elders in the Region) Project was to address the needs of underserved older adults by providing worksite education to individuals who provide nursing care to older adults in community health centers, home health agencies, and long-term care facilities. Four agencies located in a Health Professional Shortage and Medically Underserved Area participated. Project staff conducted separate focus groups with administrators and staff at each agency to determine educational needs and preferences. Curricula from the Hartford Institute, End-of-Life Nursing Education Consortium, and Geriatric Education Centers were adapted to design unique curricula for each agency and level of personnel (licensed nurse or unlicensed caregiver). Activities included focus group meetings to tailor content to the needs of each agency, on-site educational sessions, and identification of an agency champion to sustain the program after the funding ended. A case-based simulation-learning approach was used in the final year to validate application of knowledge and to facilitate teamwork and interprofessional communication. Over 100 nurses and nursing assistants and eight administrators and allied health professionals participated over the three-year period of the project. Retention over this period, independent evaluations, and simulations demonstrated participants' ability to integrate best practices into typical clinical scenarios and revealed improved communication among care providers. Tailored on-site education incorporating simulation was an effective model for translating gerontological knowledge into practice and improving the care of older adults in these multiple settings.

Central nervous system tumors of childhood and adolescence: The rehabilitation challenge of survival and "true cure"

We have described four typical clinical scenarios involving management of children and young people presenting with central nervous system (CNS) tumors. We identify the biological stages of brain development and describe the tumor-related and treatment-related late consequences faced by those travelling along the rehabilitation pathway. The long term clinical challenges for these young people extend from monitoring for tumor recurrence, second tumor development, endocrine deficits and the need for a co-ordinated approach to rehabilitation during their transition from pediatric to adult services. This is the main focus for this series, the conversion of a 'cancer cure' to a 'true cure'.

EDITORIAL: Addiction medicine: a new medical specialty in a new age of medicine

EDITORIAL: Addiction medicine: a new medical specialty in a new age of medicine

Interventional 4D motion estimation and reconstruction of cardiac vasculature without motion periodicity assumption

Anatomical and functional information of cardiac vasculature is a key component in the field of interventional cardiology. With the technology of C-arm CT it is possible to reconstruct static intraprocedural 3D images from angiographic projection data. Current approaches attempt to add the temporal dimension (4D). In the assumption of periodic heart motion, ECG-gating techniques can be used. However, arrhythmic heart signals and slight breathing motion are degrading image quality frequently. To overcome those problems, we present a reconstruction method based on a 4D time-continuous B-spline motion field. The temporal component of the motion field is parameterized by the acquisition time and does not assume a periodic heart motion. The analytic dynamic FDK-reconstruction formula is used directly for the motion estimation and image reconstruction. In a physical phantom experiment two vessels of size 3.1mm and 2.3mm were reconstructed using the proposed method and an algorithm with periodicity assumption. For a periodic motion both methods obtained an error of 0.1mm. For a non-periodic motion the proposed method was superior, obtaining an error of 0.3mm/0.2mm in comparison to 1.2mm/1.0mm for the algorithm with periodicity assumption. For a clinical test case of a left coronary artery it could be further shown that the method is capable to produce diameter measurements with an absolute error of 0.1mm compared to state-of-the-art measurement tools from orthogonal coronary angiography. Further, it is shown for three different clinical cases (left/right coronary artery, coronary sinus) that the proposed method is able to handle a large variability of vascular structures and motion patterns. The complete algorithm is hardware-accelerated using the GPU requiring a computation time of less than 3min for typical clinical scenarios.

SU-GG-T-54: A Phantom for Physics QA to Check the Accuracy of an Ir-192 Stepping Source Dwell Position and Reproducibility of Dwell Time in HDR Brachytherapy

Purpose: To determine the accuracy of dwell position, reproducibility of dwell time and effect of bending a transfer tube for Ir‐192 high‐dose rate (HDR) brachytherapy stepping source using an in‐house made phantom. Method and Materials: Experiments were performed using a Nucletron microselectron V3 (30) HDR after loading device with Ir‐192 single stepping source, Fuji Capusla XL computed radiography(CR) cassette and its reader and an in‐house made phantom. The central part of the phantom, which has alternating strips of lead and Perspex was used to check the accuracy of dwell positions while the outer part of the phantom, which consists of four different materials, namely perspex, copper,aluminium and Styro‐foam, was used to measure reproducibility of dwell time. Images were exported via network as DICOM images for further analysis by ImageJ.Results: Positional error of an HDR source smaller than 1.0 mm can be detected. Hence, it is possible to regularly check dwell positions for selected transfer tubes of a treatment plan as a quick verification of dwell positions. Reproducibility of dwell time within 0.1 second could be verified. No effect of bending a transfer tube was observed for normal clinical situations. However, under extreme cases in which the transfer tube was highly bent, the source dwell position was changed by less than 0.5mm. Conclusion: The phantom was capable of detecting dwell positional error of 1.0 mm and reproducibility of dwell time of 0.1 second. For typical clinical scenarios in which transfer tubes are bent, no effect on dwell position was observed. The phantom can be used with radiographic films or CR cassette with the latter being a preferred tool, as hospitals are phasing out film processors in favour of digital technology. The method is simple and robust for routine use.

Goals of Therapy in Common Bleeding Emergencies

Acute hemorrhage is a medical emergency requiring immediate attention, regardless of whether it manifests as blood volume lost and inadequate oxygen delivery, or as a pathologic space-occupying lesion capable of exerting elevated organ-damaging pressures. The most commonly encountered and challenging hemorrhagic emergencies to manage include bleeding secondary to traumatic injury, intracranial hemorrhage, severe gastrointestinal bleeding, and diffuse intraoperative bleeding. The critical steps taken to locate, assess, and arrest bleeding in each of these circumstances can take various paths. For all of them, the basic principles of treatment are the same: identify and correct the anatomic source and restore normal hemostatic function. The agents used to accomplish these goals, however, may differ. Several typical clinical scenarios and the evidence-based approaches used to manage such cases are presented.

Electron-beam CT as a diagnostic modality in pediatric nephrology and renal transplant surgery

Electron-beam computed tomography is an imaging technology with a variety of medical applications, primarily in cardiology due to its sub-second acquisition time enabling visualization of a beating heart. Recently, this technique has also been introduced into other fields because of lower radiation exposure compared to traditional computed tomography, as well as the strengths of post-procedural three-dimensional visualization. This report evaluates electron-beam computed tomography as a diagnostic modality in pediatric nephrology patients. Seven patients reflecting typical clinical scenarios in pediatric nephrology were reviewed with regard to the value of electron-beam computed tomography and its contribution to the diagnostic workup. Electron-beam computed tomography is noninvasive and allows three-dimensional post-processing, enabling highly accurate images while requiring less radiation and acquisition time. It is very useful for clinical questions that require a detailed description of vascular and renal anatomy.

Multi-professional Foundation Programme Simulation Training – The FAST Course.

Postgraduate medical training in the UK has recently been modified with the introduction of the Foundation Programme. Key aims of the foundation curriculum include care of acutely ill patients, with specific inclusion of non-technical skills such as communication, multi-professional teamworking and reflection. Effective, multi-professional teamworking optimises management, and therefore safety, of the acutely ill patient. Traditionally, however emphasis has not been placed upon multi-professional training in the UK. Foundation Advanced Simulation Training (FAST) is a one-day course for Foundation doctors and ward nurses, developed with support from the Trent Multi-professional Deanery. Aims and objectives are derived from the Foundation Programme curriculum. Each day accommodates 8 doctors and 4 nurses, who all receive pre-course information advising them of typical clinical scenarios, encouraging emphasis on non-technical skills, reflection and multi-professional teamworking as key objectives of the day. Candidates manage two acutely ill ward patients, and, through facilitated debriefing, reflect upon their performance and teamwork. Participants are mentored throughout the day, and aided in their production of a personal development plan, which they subsequently reflect on with their workplace educational supervisors. The aim is for the participants to develop these competences when back in their clinical environments. The participants also complete a questionnaire, exploring, inter alias, the foundation curriculum, practical competences, non-technical skills and course feedback. We will describe our experience of delivering this programme to 224 doctors and 112 nurses, highlighting its’ impact on the areas described above, and explore how well it has linked to their respective professional development needs.

Imatinib mesylate as a novel treatment option for hypereosinophilic syndrome: two case reports and a comprehensive review of the literature

Hypereosinophilic syndromes (HES) are a heterogenous group of rare disorders characterized by sustained and otherwise unexplained overproduction of eosinophils with organ involvement and consecutive dysfunction. Recent reports document the efficacy of imatinib mesylate in a large proportion of HES patients (65%). Rearrangements involving the platelet-derived growth factor receptor genes (PDGFRA and PDGFRB), both tyrosine kinase receptors, have been demonstrated to be pathogenetically linked to the dysregulated clonal overproduction of eosinophils. This refined hypothesis has been confirmed by the discovery of the novel FIP1L1-PDGFRA fusion gene, which is a gain-of-function gene on chromosome 4q12. Its product is an imatinib-sensitive tyrosine kinase, which can be found in a subset of patients with HES, particularly in those responding to treatment with imatinib mesylate. Here, we sum up recent knowledge of clinical features, pathophysiology and novel treatment aspects of HES by performing a comprehensive search of the available literature and report on 94 patients. We particularly address the issue of organ involvement and specific characteristics of the variable clinical pictures. In addition, two cases will be presented, which illustrate typical clinical scenarios and treatment outcome.