Muscle magnetic resonance imaging shows distinct diagnostic patterns in Welander and tibial muscular dystrophy.

Objectives: This is a report on a retrospective muscle magnetic resonance imaging (MRI) study on 11 patients affected by Welander distal myopathy (WDM) and 22 patients with tibial muscular dystrophy (TMD) carried out in order to define the pattern and characteristics of muscle involvement.

Results: WDM patients showed involvement of gastrocnemius, soleus, tibial anterior (TA) and extensor digitorum longus (EDL), as well as hamstrings and hip adductor muscles. TMD patients showed involvement of the TA and EDL muscles, and in some patients also hamstring and posterior compartment muscles of the legs.

Association between pleural plaques and coronary heart disease.

Objective: The aim of this study was to verify a clinical impression that patients with coronary heart disease disproportionately frequently have calcified pleural plaques.

Methods: Chest X-rays were collected from 148 patients referred consecutively to the Helsinki University Central Hospital for coronary angiography and from 100 consecutive lung cancer patients seen at the same hospital. The radiographs were analyzed for the presence of calcified pleural plaques according to the classification the International Labour Office.

The efficacy of a continuous quality improvement (CQI) method in a radiological department. Comparison with non-CQI control material.

Objective: To study the efficacy of continuous quality improvement (CQI) compared to ordinary management in an on-duty radiology department.

Material And Methods: Because of complaints regarding delivery of on-duty radiological services, an improvement was initiated simultaneously at two hospitals, at the HUCH (Helsinki University Central Hospital) utilising the CQI-method, and at the OUH (Oulu University Hospital) with a traditional management process. For the CQI project, a team was formed to evaluate the process with flow-charts, cause and effect diagrams, Pareto analysis and control charts.

Antimyosin scintigraphy compared with magnetic resonance imaging in inflammatory myopathies.

Objective: To compare indium In 111 altumomab pentetate-labeled antimyosin scintigraphy with magnetic resonance imaging (MRI) in the diagnosis and follow-up of patients with myositis.

Design And Methods: Sixteen patients with polymyositis and 1 patient with dermatomyositis, all verified with biopsy samples, were examined during diagnostic evaluation with antimyosin antibody scintigraphy and low-field MRI of the thighs and calves using T1- and T2-weighted sequences. Both examinations were repeated 6 to 22 months after therapeutic intervention with antiinflammatory drugs.

Magnetic resonance imaging is superior to computed tomography and ultrasonography in imaging infectious liver foci in acute leukaemia.

We conducted a prospective study in order to compare ultrasonography, computed tomography and magnetic resonance imaging in the detection of liver foci in patients with acute leukaemia and clinical suspicion of hepatic candidiasis. 28 adult patients fulfilling set entry criteria after recovery from neutropenia were studied. Lesions in the liver were detected by at least one imaging modality in 21 patients: by ultrasonography in 7 (33% of detected cases), computed tomography in 12 (57%) and by magnetic resonance imaging in 20 patients (95%).

Low-field MR imaging for the assessment of therapy response in musculoskeletal infections.

Fifty-one patients with musculoskeletal infection were imaged by repeated MR imaging at ultra low-field and low-field strength. Soft-tissue infection, osteomyelitis, septic arthritis, and spondylitis were studied. The MR finding was scored according to the signal intensity (SI) on T2-weighted images (T2WI), and correlated with the values of serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and peripheral white blood cell (WBC) count.

191Os/191mIr-generator for studying arterial blood flow in experimental animal models.

Iridium-191m (191mIr, t1/2 = 4.96 sec), an ultra-short lived tracer, has turned out to be suitable for gamma imaging. It can be obtained in high yields from an 191Os/191mIr-generator with a low 191Os breakthrough.

Improvement of bedside chest radiograph quality using a high ratio grid and an electronic angle meter for alignment.

An electronic level was used to ensure proper alignment of a high ratio grid at bedside chest radiography. The image quality was clearly improved. The method is inexpensive and simple to use.

Quality assurance of the bedside chest radiography process.

The bedside chest radiography process was analyzed in terms of modern quality management guidelines and the sources of quality problems were identified. In order to analyze systematically the various quality factors, the process was described in a top-down fashion with the aid of data flow diagrams. Two internal quality control points and one external point were found in the process.

Effect of digital edge-enhancement on the visibility of normal parenchymal lung markings.

Digital 'conventional-like' (C-L) and edge-enhanced (E-E) posteroanterior chest roentgenograms of 42 healthy individuals were ranked twice (interval of at least 5 days) in the order of increasing lung parenchymal markings (a total of four rankings). This was done by three radiologists, two residents, one medical student and one radiographer. There was a good general consistency of rankings for both the C-L and E-E images.

T1 rho dispersion imaging of diseased muscle tissue.

T1 rho dispersion, or the frequency dependence of T1 relaxation in the rotating frame, was used for in vivo muscle tissue characterization in 13 patients with primary skeletal muscle disease and in eight normal subjects for comparison. T1 rho dispersion measurements represent a new approach to magnetic resonance tissue characterization, possibly reflecting the macromolecular constituents of tissue. A definite, statistically significant, difference was found between the relative T1 rho dispersion values of normal and diseased muscle tissue.

Observed lung markings in normal chest roentgenograms.

The digital chest posterior-anterior roentgenograms of 42 healthy individuals were ranked twice (interval of at least 5 days) in the order of increasing lung parenchymal markings. The evaluations were made by three radiologists, two residents, a medical student and a radiographer. All observers regardless of their radiological experience showed good intraobserver correlations between their two subsequent rankings (p < 0.

The effect of digital unsharp-mask filtering on the signal-to-noise ratio in computed radiography.

The effect of image processing in computed radiography (CR) has been analyzed in many ROC studies. The results have not shown great diagnostic improvements, except in some special occasions. The theoretical effect of image enhancement on the signal-to-noise ratio in CR images has so far not been assessed.

Computed radiography and image workstation from the radiologist's point of view.

A computed radiography system (Digiscan, Siemens) connected to an image workstation (Siemens) has been used for 1 1/2 years in our department. The image quality is good and it has been possible to reduce radiation dose by about 30% without any appreciable loss of image quality. The image workstation has been used in cases where image postprocessing is considered to be useful.

The scatter-to-primary ratio as a function of varying X-ray absorption measured by computed radiography.

Some scatter studies have previously been conducted using film as a detector. The serious limitations caused by the narrow latitude, the non-linear density response, and the required optical densitometric measurements of film can be avoided by computed radiography (CR) which provides linear numeric data over a wide dynamic range. The imaging plate is used as a large-area detector and the data is analyzed from the computer memory.

The effect of scatter reduction on the signal-to-noise ratio in computed radiography.

Signal-to-noise ratio (SNR) in computed radiography (CR) was assessed by using the computerized image data from storage phosphor radiographs in a modification of the Rose model. A multiple pencil-beam (MPB) imaging device, a conventional 1:12 grid, and an air gap of 90 cm were compared in terms of improvement of the signal-to-noise ratio caused by the reduction of scatter. The MPB device showed better SNRs by a factor of 1.

Combination of multiple pencil-beam imaging to computed storage phosphor radiography: a new method.

Computed radiography (CR) with storage phosphors offers a wide dynamic range and improved sensitivity compared to film-screen technology. CR was combined in this study with a prototype multiple pencil-beam (MPB) imaging device which has been shown to be very effective in scatter reduction. The combination was analyzed and compared to the standard technique of grid screening in two ways: a free-response ROC (FROC) analysis was first performed followed by a blinded test arrangement for visual analysis of image quality in a series of computed radiography of the lumbar spine by both the MPB and grid modalities.

Detection of soft-tissue and skeletal infections with ultra low-field (0.02 T) MR imaging.

To evaluate the use of ultra low-field (0.02 T) magnetic resonance (MR) imaging in the diagnosis of musculoskeletal infection, MR examinations with T2 weighted sequences were performed in 61 patients thought to be suffering from one of four major diagnostic categories: Soft-tissue abscesses (n = 22), osteomyelitis (n = 21), septic arthritis (n = 9) and spondylitis (n = 9). Infection was confirmed for 37 of these 61 patients.

Acute rhabdomyolysis: evaluation with magnetic resonance imaging compared with computed tomography and ultrasonography.

Fifteen patients with acute rhabdomyolysis were evaluated with low field magnetic resonance (MR) imaging and the results compared with those obtained using computed tomography (CT) and ultrasonography (US). With MR imaging, abnormal muscles with areas of increased signal intensity were seen in every patient, which probably reflects increased water content or increased mobility of water molecules caused by inflammatory reaction and oedema in the injured and necrotic muscles. Computed tomography without intravenous contrast medium demonstrated abnormal muscles in most patients examined with this modality.

Magnetic resonance imaging of tibial shaft fracture repair.

Magnetic resonance imaging (MRI) of normal fracture repair was evaluated in six randomly chosen adult patients with solitary, closed fractures of the tibial shaft by obtaining serial MRI scans until union of the fracture. The mean time to union was 14.3 weeks.

Reduction of radiation scatter with a multiple pencil-beam imaging device.

A prototype device consisting of a focused array of several scanning collimator plates that produce multiple pencil beams has been constructed for radiographic imaging. Under normal imaging conditions, the scatter-to-primary ratio resulting from this device is less than 10%. High-contrast radiographs can be produced without increasing patient radiation dose.