[Acceptance analysis of a digital picture distribution in a filmless university hospital].

Purpose: A prospective evaluation before and after the introduction of PACS should evaluate the level of acceptance by the referring physicians and indicate possible weaknesses.

Materials And Methods: In a hospital with 816 beds, questionnaires were sent to all referring physicians before and after the introduction of PACS to inquire how the physicians deal with radiological images.

Results: Without PACS, 62 % of the referring physicians spent up to one hour per day searching for radiological images.

Alterations of cerebral metabolism in patients with diabetes mellitus studied by proton magnetic resonance spectroscopy.

To evaluate possible pathophysiologic links between cerebral changes in diabetic patients detected by proton magnetic resonance spectroscopy and clinical as well as laboratory parameters. The brains of 30 patients with diabetes mellitus and 30 healthy volunteers were examined using a STEAM sequence (TR 1500 ms, TE 20 ms). We measured in occipital gray matter and parietal white matter in a 1.

MRI of the abnormal cervical spinal cord using 2D spoiled gradient echo multiecho sequence (MEDIC) with magnetization transfer saturation pulse. A T2* weighted feasibility study.

Objectives: The aim of this study was to assess the potential of heavily T2* weighted 2D spoiled gradient echo multiecho sequence MEDIC (multi echo data image combination) with magnetization transfer saturation pulse (MTS) for detecting abnormality of the cervical spinal cord.

Methods: 11 patients, 5 women and 6 men aged from 14 to 79 years (mean age 51.18 years), with traumatic, hemolytic-hemorrhagic or neoplastic diseases of the cervical spinal cord were examined with MRI.

[Cost analysis of radiological interventional procedures and reimbursement within a clinic].

Purpose: Analysis of costs for vascular radiological interventions on a per patient basis and comparison with reimbursement based on GOA (Gebührenordnung für Arzte) and DKG-NT (Deutsche Krankenhausgesellschaft-Nebenkostentarif).

Material And Methods: The ten procedures most frequently performed within 12 months were evaluated. Personnel costs were derived from precice costs per hour and estimated procedure time for each intervention.

Routine chest radiography using a flat-panel detector: image quality at standard detector dose and 33% dose reduction.

Objective: The purpose of this study was to evaluate the effectiveness of a large-area, flat-panel X-ray detector for performing routine chest radiography at two different detector doses.

Materials And Methods: The chest radiographs of 50 patients (age range, 16-79 years; mean age, 57 years) were obtained at two different detector dose levels. Digital images were taken from the same patients in posteroanterior and lateral views with detector doses of 2.

Comparison of 2D and 3D MRI of the optic and oculomotor nerve anatomy.

A total of 30 healthy volunteers underwent magnetic resonance imaging (MRI) with T1 weighted (w.) 3D magnetization prepared rapid gradient echo (MP-RAGE), T2 w. 2D turbo spin echo (TSE) and T2* w.

[The PACS concept of the University of Regensburg].

Aim: Planning a PACS (Picture Archiving and Communication System) with the aim of a filmless hospital. The service for the referring physicians should be optimised.

Methods: Statistical analysis of data from the RIS (Radiological Information System), customer survey, workflow analysis and cost effectiveness analysis was the basis for planning the PACS.

Visualization of the IXth to XIIth cranial nerves using 3-dimensional constructive interference in steady state, 3-dimensional magnetization-prepared rapid gradient echo and T2-weighted 2-dimensional turbo spin echo magnetic resonance imaging sequences.

The purpose of this study was to evaluate the visibility of the IXth to XIIth cranial nerves using different magnetic resonance sequences. Thirty healthy volunteers underwent magnetic resonance imaging at 1.5 T using 3-dimensional constructive interference in steady state (CISS) sequence (TR = 17 ms, TE = 8.

Comparison of two-dimensional gradient echo, turbo spin echo and two-dimensional turbo gradient spin echo sequences in MRI of the cervical spinal cord anatomy.

The aim of this study was to assess the detectability and distinguishability of the cervical spinal cord, the anterior and posterior spinal roots and of the internal anatomy of the cord (distinction of grey and white matter). For this purpose 20 healthy volunteers were examined using a 1.5 T MR unit with 20 mT/m gradient strength and a dedicated circular polarized neck array coil.

Comparison of 2-D turbo spin echo and 3-D gradient echo sequences for the detection of the trigeminal nerve and branches anatomy.

The aim of this study was to assess the detectability of the trigeminal nerve and its branches using T1 weighted (w.) 3-D magnetization prepared rapid gradient echo (MP-RAGE), T2* w. 3D CISS and T2 w.

Comparison of a T2* w. 3D CISS and a T2 w. 3D turbo spin echo sequence for the anatomical study of facial and vestibulocochlear nerves.

Thirty healthy volunteers were examined with a T2* w. 3D CISS and a T2 w. 3D turbo spin echo (TSE) sequence in order to compare the facial and vestibulocochlear nerve detectability in the cerebellopontine angle and the internal auditory canal.

MRI detection of olfactory bulb and tract.

Thirty healthy volunteers underwent MRI with 3D MP-RAGE, 3D CISS and 2D turbo spin echo sequences to compare the detectability of olfactory fibers, bulb, tract, and sulcus. The overall detectability was slightly better using MP-RAGE compared with CISS. Both 3D sequences were superior to 2D turbo spin echo.

Solid-state spectroscopic analysis of lignins from several Austral hardwoods.

In order to gain information about lignin molecular characteristics with a direct bearing on the remarkable susceptibility of some Austral hardwoods to biological delignification, milled-wood lignins were isolated and analyzed by spectroscopic techniques in the solid state. Cross polarization and magic-angle spinning 13C nuclear magnetic resonance (13C CPMAS NMR) and Fourier-transform infrared (FTIR) spectra of the lignin preparations were obtained. The most diagnostic peaks were assigned and quantified as percentages of the total spectral area, and the differences observed discussed in terms of lignin composition.

Analysis of the availability and completeness of previous radiological examinations related to plain films.

Purpose: To evaluate the availability and completeness of previous radiological examinations.

Material And Methods: Seven different types of examinations were analysed separately: 1) chest examinations, 2) bedside chest examinations, 3) skeletal examinations, 4) angiographic examinations, 5) mammographic examinations, 6) CT examinations, and 7) MR examinations. A retrospective part of the study covered the calendar year 1997, while a prospective part referred to 1998.

[Digital flat image detector technique based on cesium iodide and amorphous silicon: experimental studies and initial clinical results].

Purpose: Experimental and clinical evaluation of a digital flat-panel X-ray system based on cesium iodide (CsI) and amorphous silicon (a-Si).

Methods: Performance of a prototype detector was compared with conventional screen-film radiography (SFR) using several phantom studies. Foreign bodies, fractures, osteolyses, and pulmonary lesions were analyzed.

Clinical application of a flat-panel X-ray detector based on amorphous silicon technology: image quality and potential for radiation dose reduction in skeletal radiography.

Objective: The purpose of this study was to compare images obtained with a self-scanning, flat-panel X-ray detector based on amorphous silicon technology with conventional screen-film radiographs and to evaluate the possibility of radiation dose reduction in skeletal radiography.

Subjects And Methods: One hundred twenty patients were examined prospectively using a conventional screen-film system (speed, 400; detector dose, 2.5 microGy) and a prototype digital amorphous silicon detector (simulated speed, 400 and 800, n = 120; simulated speed, 1600, n = 40).

Detection of simulated chest lesions with normal and reduced radiation dose: comparison of conventional screen-film radiography and a flat-panel x-ray detector based on amorphous silicon.

Rationale And Objectives: The authors compared a solid-state amorphous silicon (a-Si) detector and screen-film radiography (SFR) with regard to the detection of simulated pulmonary lesions. Evaluation of the impact of a dose reduction of 50% with this digital flat-panel detector was of special interest.

Methods: A self-scanning flat-panel detector, based on a-Si technology with 143 x 143 microm pixel size, 1 k x 1 k matrix and 12-bit digital output was used.

Amorphous silicon, flat-panel, x-ray detector versus screen-film radiography: effect of dose reduction on the detectability of cortical bone defects and fractures.

Rationale And Objectives: The purpose of this phantom study was to assess the diagnostic performance of a self-scanning, solid-state amorphous silicon (a-Si) detector in skeletal radiography using different exposure parameters.

Methods: A flat-panel detector (15 cm x 15 cm), based on a-Si technology with 143 microm x 143 microm pixel size, 1k x 1k matrix, and 12 bit digital output was used. State-of-the-art screen-film radiography (SFR; speed 400, detector dose 2.

Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) of intracranial lipomas.

We show a detailed magnetic resonance (MR) examination of two rare pericallosa lipomas with a fat suppression imaging sequence and proton MR spectroscopy. For comparison, subcutaneous fat and lipids in glioblastomas were examined with H MR spectroscopy in vivo and ex vivo. Fat suppression makes the identification of lipomas simple.

Auditory event-related cerebral potentials (P300) in hepatic encephalopathy--topographic distribution and correlation with clinical and psychometric assessment.

Background/aims: Early cognitive disturbances in patients with cirrhosis (Ci) are difficult to assess. Therefore, we evaluated the role of topographic auditory evoked cerebral potentials (P300-EP).

Methodology: Prospective longitudinal study.

Flat-panel x-ray detector using amorphous silicon technology. Reduced radiation dose for the detection of foreign bodies.

Rationale And Objectives: The authors evaluate a new flat-panel x-ray detector (FD) with respect to foreign body detection and reduction of radiation dose compared with screen-film radiography.

Methods: Flat-panel x-ray detector is based on amorphous silicon technology and uses a 1 k x 1 k photo-detector matrix with a pixel size of 143 x 143 microns and 12-bit digital output. A thallium-dotted cesium iodide scintillation layer converts x-rays into light.

Cerebral abnormalities in patients with cirrhosis detected by proton magnetic resonance spectroscopy and magnetic resonance imaging.

Hepatic encephalopathy is a common problem in cirrhosis. The pathogenesis of this complication of advanced liver disease still remains unclear. Magnetic resonance spectroscopy was used to assess prospectively cerebral metabolism in 51 patients with histologically proven cirrhosis (Child-Pugh classes A, B, and C, 18, 18, and 15, respectively) and 36 healthy volunteers.

Cerebral metabolite patterns in dialysis patients: evaluation with H-1 MR spectroscopy.

Purpose: To analyze metabolic changes in the brain of patients undergoing dialysis.

Materials And Methods: Sixteen patients undergoing hemodialysis, 10 patients undergoing continuous ambulatory peritoneal dialysis (CAPD), and 42 healthy volunteers underwent magnetic resonance (MR) spectroscopy and MR imaging. Spectra were obtained from one occipital gray matter voxel and one parietal white matter voxel.

Stereochemistry and size of sugar head groups determine structure and phase behavior of glycolipid membranes: densitometric, calorimetric, and X-ray studies.

The role carbohydrate moieties play in determining the structure and energetics of glycolipid model membranes has been investigated by small- and wide-angle X-ray scattering, differential scanning densitometry (DSD), and differential scanning microcalorimetry (DSC). The dependence of a variety of thermodynamic and structural parameters on the stereochemistry of the OH groups in the pyranose ring and on the size of the sugar head group has been studied by using an homologous series of synthetic stereochemically uniform glyceroglycolipids having glucose, galactose, mannose, maltose, or trimaltose head groups and saturated ether-linked alkyl chains with 10, 12, 14, 16, or 18 carbon atoms per chain. The combined structural and thermodynamic data indicate that stereochemical changes of a single OH group in the pyranose ring can cause dramatic alterations in the stability and in the nature of the phase transitions of the membranes.