Improving efficacy and efficiency through the implementation of a new organisational model in a Radiation Oncology Department

Background. To evaluate a new organisational model, "process management" (PM), implemented in the Hospital Universitario Virgen de la Victoria (HUVV) compared with traditional models used in other Radiation Oncology Departments (RODs), in terms of efficacy and efficiency. Methods. The study period ranged from September 2011 to August 2012. Efficacy was assessed, comparing the number of patients attended in first consultation and treated per month, average waiting time from referral to first visit and average waiting time from first visit to treatment. Data were collected from two public hospitals in Andalusia: the HUVV and another Public Hospital in Andalusia (PHA1). Efficiency was assessed comparing the costs per patient attended in first visit and treated at HUVV in 2012 compared with those of a second Public Hospital in Andalusia (PHA2) for 2008. The number of sessions saved using hypofractionation versus classical schemes during the year 2012 in HUVV was estimated, and the money saved was calculated. Results. In the efficacy analysis, we found significant differences in the average waiting time for first visit, start of treatment, and the number of patients seen and treated annually. After calculating the total cost generated in the ROD, the efficiency analysis showed a lower cost per patient attended in first visit (EUR 599.17) and per patient treated (EUR 783.50), with a saving of 6035 sessions using hypofractionated schemes. Conclusions. Process management in an ROD reduces time, both to first medical visit and to treatment initiation, allowing an optimisation of linear accelerator (LINAC) capacity (AU)

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Improving efficacy and efficiency through the implementation of a new organisational model in a Radiation Oncology Department.

BACKGROUND: To evaluate a new organisational model, "process management" (PM), implemented in the Hospital Universitario Virgen de la Victoria (HUVV) compared with traditional models used in other Radiation Oncology Departments (RODs), in terms of efficacy and efficiency. METHODS: The study period ranged from September 2011 to August 2012. Efficacy was assessed, comparing the number of patients attended in first consultation and treated per month, average waiting time from referral to first visit and average waiting time from first visit to treatment. Data were collected from two public hospitals in Andalusia: the HUVV and another Public Hospital in Andalusia (PHA1). Efficiency was assessed comparing the costs per patient attended in first visit and treated at HUVV in 2012 compared with those of a second Public Hospital in Andalusia (PHA2) for 2008. The number of sessions saved using hypofractionation versus classical schemes during the year 2012 in HUVV was estimated, and the money saved was calculated. RESULTS: In the efficacy analysis, we found significant differences in the average waiting time for first visit, start of treatment, and the number of patients seen and treated annually. After calculating the total cost generated in the ROD, the efficiency analysis showed a lower cost per patient attended in first visit (EUR 599.17) and per patient treated (EUR 783.50), with a saving of 6035 sessions using hypofractionated schemes. CONCLUSIONS: Process management in an ROD reduces time, both to first medical visit and to treatment initiation, allowing an optimisation of linear accelerator (LINAC) capacity.

Modular multipin electrodes for comfortable dry EEG.

Electrode and cap concepts for continuous and ubiquitous monitoring of brain activity will open up new fields of application and contribute to increased use of electroencephalography (EEG) in clinical routine, neurosciences, brain-computer-interfacing and out-of-the-lab monitoring. However, mobile and unobtrusive applications are currently hindered by the lack of applicable convenient and reliable electrode and cap systems. We propose a novel modular electrode concept based on a flexible polymer substrate, coated with electrically conductive metallic films. The overall concept enables design adaptation to different head regions and cap designs. We describe the single modules of the system and investigate the influence of electrode pin number, coating material and adduction force on electrode-skin impedance and perceived wearing comfort. Our results contribute to rapid and comfortable multichannel dry EEG.

Novel Multipin Electrode Cap System for Dry Electroencephalography.

Current usage of electroencephalography (EEG) is limited to laboratory environments. Self-application of a multichannel wet EEG caps is practically impossible, since the application of state-of-the-art wet EEG sensors requires trained laboratory staff. We propose a novel EEG cap system with multipin dry electrodes overcoming this problem. We describe the design of a novel 24-pin dry electrode made from polyurethane and coated with Ag/AgCl. A textile cap system holds 97 of these dry electrodes. An EEG study with 20 volunteers compares the 97-channel dry EEG cap with a conventional 128-channel wet EEG cap for resting state EEG, alpha activity, eye blink artifacts and checkerboard pattern reversal visual evoked potentials. All volunteers report a good cap fit and good wearing comfort. Average impedances are below 150 kΩ for 92 out of 97 dry electrodes, enabling recording with standard EEG amplifiers. No significant differences are observed between wet and dry power spectral densities for all EEG bands. No significant differences are observed between the wet and dry global field power time courses of visual evoked potentials. The 2D interpolated topographic maps show significant differences of 3.52 and 0.44% of the map areas for the N75 and N145 VEP components, respectively. For the P100 component, no significant differences are observed. Dry multipin electrodes integrated in a textile EEG cap overcome the principle limitations of wet electrodes, allow rapid application of EEG multichannel caps by non-trained persons, and thus enable new fields of application for multichannel EEG acquisition.

Novel flexible Dry multipin electrodes for EEG: Signal quality and interfacial impedance of Ti and TiN coatings.

Conventional Silver/Silver-Chloride electrodes are inappropriate for routine high-density EEG and emerging new fields of application like brain computer interfaces. A novel multipin electrode design is proposed. It enables rapid and easy application while maintaining signal quality and patient comfort. The electrode design is described and impedance and EEG tests are performed with Titanium and Titanium Nitride coated electrodes. The results are compared to conventional reference electrodes in a multi-volunteer study. The calculated signal parameters prove the multipin electrode concept to reproducibly acquire EEG signal quality comparable to Ag/AgCl electrodes. The promising results encourage further investigation and can provide a technological base for future preparation-free multichannel EEG systems.

Novel flexible dry PU/TiN-multipin electrodes: first application in EEG measurements.

Dry biosignal electrodes for electro-encephalography (EEG) are an essential step for realization of ubiquitous EEG monitoring and brain computer interface technologies. We propose a novel electrode design with a specific shape for hair layer interfusion and reliable skin contact. An electrically conductive Titanium-Nitride (TiN) thin layer is deposited on a polyurethane substrate using a multiphase DC magnetron sputtering technique. In the current paper we describe the development and manufacturing of the electrode. Furthermore, we perform comparative EEG measurements with conventional Ag/AgCl electrodes in a 6-channel setup. Our results are promising, as the primary shape of the EEG is preserved in the signals of both electrodes sets, according to recordings of spontaneous EEG and visual evoked potentials. The variance of both signals is in the same order of magnitude. The Wilcoxon-Mann-Whitney two-sample rank-sum test revealed no significant differences for 25 of the 28 compared signal episodes. Hence, our novel electrodes show equivalent signal quality compared to conventional Ag/AgCl electrodes.

[The value of spiral-CT in primary and secondary liver neoplasms]. / Wertigkeit der Spiral-CT bei primären und sekundären Lebermalignomen.

Sixty-one patients in whom primary or secondary malignomas of the liver were suspected on the basis of ultrasound examination were examined with spiral CT and sequential CT during i.v. administration of contrast medium. In four further cases spiral CT-angiography (spiral-CTA) was performed. Advantages and disadvantages of spiral volume CT are described.

[Value of neuroradiologic procedures in preoperative assessment of cervical myelopathy]. / Wertigkeit neuroradiologischer Verfahren bei der präoperativen Beurteilung der zervikalen Myelopathie.

The diagnostic value of computed tomography (CT), myelography, myelo-CT and magnetic resonance imaging (MRI) was retrospectively investigated in 94 patients in whom Cloward's operation had been performed due to symptoms of cervical myelopathy (CM). In 55 patients with "classical" cervical spondylotic myelopathy all investigated diagnostic procedures demonstrated a comparably high degree of sensitivity and specificity, thus proving comparable for diagnosing pathological alterations of the cervical spine. In 39 patients with CM as a consequence of an acute cervical disk prolapse, however, MRI was superior and offered the highest diagnostic accuracy. The following general diagnostic strategy in patients with CM can be suggested: Conventional plain film radiography of the cervical spine, axial CT of the involved segments and MRI of the cervical spine in sagittal and transversal orientation, using T1 and T2 weighted pulse sequences. The combined use of these techniques allows the exact evaluation of any relevant structure alterations of the cervical spine that determine differential therapeutic approaches.

[Interpretation of MR tomography findings in trauma surgery]. / Zur Interpretation kernspintomographischer Befunde in der Unfallchirurgie.

MR-Imaging is well established as the most sensitive method for the diagnosis of avascular necrosis of the femoral head. In this paper preliminary results are analyzed in an attempt to clarify whether as in a vascular necrosis of the femoral head. MR changes after trauma or surgery allow conclusions concerning the vitality of the bone. Comparison of clinical, MR and histological findings revealed that we cannot yet differentiate between fibrosis of the bone marrow with sustained vitality of the osteocytes and bone necrosis. Therefore, conclusions with implications for therapy should be drawn with extreme care.

[A simple method for MRI-assisted radiotherapy planning in brain tumors]. / Eine einfache Methode zur MRT-gestützten Bestrahlungsplanung von Hirntumoren.

A simple method for radiation therapy planning of brain tumors is presented. Therapy portals of midline tumors can easily be determined by comparing sagittal MRI scans with the lateral simulator radiograph. By addition of appropriately processed MR-tomograms a similar planning is possible for parasagittal tumors. Digital data exchange between different operating systems is not necessary with our simple method, problems with varying input/output standards and expensive hardware requirements are thus avoided.

[Magnetic resonance tomography using gadolinium-DTPA in the diskectomy syndrome--a reliable method of identifying a recurrent prolapse in scar tissue]. / Die Kernspintomographie mit Gadolinium-DTPA beim Diskektomie-Syndrom--eine zuverlässige Methode zur Identifizierung eines Rezidivprolapses im Narbengewebe.

The non invasive diagnostic possibilities of MR have resulted in better diagnosis of degenerative spinal diseases. Twenty-one patients with failed back surgery syndrome (postdiscectomy syndrome) were studied to evaluate the possibility of 1-Tesla magnetic resonance (MR) imaging with gadolinium diethylene triamine pentaacetic acid (Gd-DTPA) in differentiating post operative scar tissue from recurrent disc herniation. The enhanced MR studies correctly depicted the character of abnormal epidural tissue in all patients. We conclude that MR with GD-DTPA might be the method of choice to differentiate reliably postoperative epidural fibrosis from recurrent disc prolapse.

[Intracranial hemorrhage in MRT]. / Die kranielle Blutung in der MRT.

About 10% of all intracranial findings in cranial MRI were hemorrhages, or findings associated with bleeding. There was great variation in the hemorrhages as a result of their location and their age, and this could disguise the underlying lesions. Therefore a knowledge of the typical appearance of spontaneous bleeding and tumor bleeding is necessary for interpretation of the MRI findings. During its course, cerebral bleeding shows all of the known interactions between biochemical and histological factors and MRI signal. Thus, an understanding of the variations during the clinical course of bleeding is helpful for a better understanding of contrast mechanisms in MRI.

[Transient osteoporosis or femur head necrosis? Early diagnosis using MRT]. / Transitorische Osteoporose oder Femurkopfnekrose? Frühdiagnose mit der MRT.

Transient osteoporosis of the hip is a syndrome that does not seem to be widely known; this is also true for its radiological appearance. It is often mistaken for avascular necrosis of the femoral head, metastatic or inflammatory disease. These differential diagnoses lead to more or less invasive procedures, although transient osteoporosis does not require more than immobilisation for complete remission. MRI was done in 38 patients with acute hip pain, 13 had femoral head necrosis and 8 transient osteoporosis. Follow-up studies via MRI in patients with transient osteoporosis revealed 3 stages (diffuse, focal, residual) during the clinical course of which stage II is similar to femoral head necrosis but always without the typical sclerotic rim.

Bone grafting in total hip replacement. Preliminary results with MRI.

MRI of ten hip joints in nine patients with total hip replacement and reconstruction of the acetabulum with autologous bone grafts, were reviewed. The viability of inserted bone grafts was clearly documented by MRI. Characteristic differences in signal intensity between autologous and homologous bone grafts are discussed. Despite extended metallic artifacts in the operated region, sufficient diagnostic information was available in most cases. No side effects were reported.

[MR tomography of astrocytic tumors (I-III)]. / MR-Tomographie astrozytärer Tumoren (I-III).

Magnetic resonance (MR) imaging was performed on 37 patients with histologically confirmed astrocytomas (I-III). In addition, the MR tissue parameters T1, T2 and proton density (RHO) were analysed by an interlaced CPMG spin echo sequence. Characteristic morphologic tumour patterns which subdivide astrocytomas into each different tumour grade are presented. Quantitative analysis of MR tissue parameters provides a statistically proven classification of each tumour grade and allows differentiation between "semibenign" astrocytomas (II) and "relatively malignant" astrocytomas (III), with high accuracy.

MR imaging of cerebral tumors: state of the art and work in progress.

MR imaging of the brain has made tremendous progress during the last years. This technique is generally superior to computed tomography (CT) in brain tumors, due to its capability for direct imagining in various planes and its high tissue contrast. Moreover, the detectability and differentiation of extraaxial tumors, previously the domain of CT, has been improved with paramagnetic contrast agents (PCA). Although, the sensitivity of MRI for intracranial tumors is unchallenged, the specificity for such tumors is not remarcably greater than that of CT. Differentiation between high grade glioma, abscess and metastasis still requires biopsy for definitive diagnosis. Methods for improvement of specificity--tissue characterization--are currently being evaluated in a clinical setting. Further development in this field is necessary before such methods can be applied on a routine basis.

[Results of nuclear magnetic resonance tomography studies in endocrine orbitopathy]. / Ergebnisse kernspintomographischer Untersuchungen bei endokriner Orbitopathie.

Magnetic resonance imaging (T1- and T2-weighted) was performed in 65 patients with Graves' disease. In addition, T2 relaxation times of each ocular muscle were measured. Of the muscles thus studied, 54.8% showed a thickening in coronary tomograms. An interaction between the optic nerve and the thickened ocular muscles at the apex of the orbit was suspected in 30.1%. It could not be confirmed that the thickening of the muscles and the T2 value were related. However, there was a high correlation between the rise in intraocular pressure and the T2 relaxation time. These results imply that the T2 relaxation time is extremely useful in interpreting the activity of Graves' disease and provide a diagnostic tool of prognostic value in monitoring and treating this disease.