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. The verified abscesses, arthritis, spondylitis and acute osteomyelitis could be detected by 0.02 T MR. The sensitivity was poor in cases of chronic osteomyelitis. There was one false positive finding in a patient with a possible soft tissue infection. The 0.02 T MR examination failed four times. Two patients were too heavy and another 2 patients had magnetic material in or near the scanning field. Compared with computed tomography and isotope scanning, 0.02 T MR proved a little more informative, but without any statistical significance.

Effect of radiologist supervision on technician performance and image quality in radiography of middle face trauma.

Image quality in radiography of middle face trauma was compared within and outside office hours on the basis of the visibility of diagnostically important structures, and an evaluation of the major patient- and technician-related factors influencing image quality. Image quality was statistically significantly better within than outside office hours. This was due to the technician-related factors of patient positioning, X-ray beam limiting and centering. Since the analysis of variance revealed that alcohol intoxication (three times more common outside than within office hours) had no statistically significant effect on image quality, the difference must have been due to the only remaining variable--radiologist supervision, which was present only within office hours.

Atlantoaxial facet joint arthritis in the rheumatoid cervical spine. A panoramic zonography study.

Twenty-three patients with severe, longterm (22 years, range 8-36) rheumatoid arthritis were evaluated for rheumatoid changes in the atlantoaxial facet joints using a panoramic zonography program. Ten patients had vertical subluxation of the odontoid process. In 9 of 10 cases this mode of subluxation was associated with grade 3-4 arthritis in the facet joints. Our findings indicate atlantoaxial facet joint arthritis with bilateral collapse of the lateral facet joint masses as a cause of vertical subluxation. Furthermore, we suggest that panoramic zonography investigation is a valuable contribution to the pattern of radiographic examination of the atlantoaxial facet joint arthritis, especially for evaluation of its clinical counterparts: nonreducible lateral head tilt and vertical atlantoaxial subluxation.

The effects of clinical data on radiological diagnostic performance in middle-face trauma.

To determine the effect of clinical information on the radiological diagnostic performance in middle-face injury, the medical records and radiographs of 618 patients with middle-face injury were reviewed. The information value of clinical data given in each x-ray requisition was evaluated. The radiological diagnoses were compared with the final clinical diagnoses both retrospectively and prospectively (with and without clinical data). Knowledge of clinical data with statistical significance changed the reader's decision threshold towards improved sensitivity but poorer specificity. Clinical data did not improve the radiologists' performance. Clinical data may be helpful in diagnostic tasks rather by increasing the sensitivity than the specificity.

The desmoid tumor. II. Analysis of factors possibly contributing to the etiology and growth behavior.

Eighty histologically verified cases of the desmoid tumor (DT) have been analyzed with regard to factors possibly contributing to the etiology and/or growth behavior of this uncommon neoplasm. Considering the four statistical age components, the "fertile" female and "menopausal" varieties of the DT grew distinctly faster (0.1 less than P greater than 0.05 and less than 0.05), and the female "juvenile" variety distinctly slower (0.1 less than P greater than 0.05) than the male DTs. In a visual estimate, the fertile female patients had a significant (P less than 0.01) predisposition to estrogen predominance, while fewer patients than expected displayed progesterone predominance or were at balance (P = NS and less than 0.01, respectively). Thirty-two per cent of the patients with an abdominal DT had been previously operated in the region of subsequent tumor growth. Significantly more pregnancies were observed in patients with abdominal DT than with extra-abdominal DT (P less than 0.05). On only one occasion did sigmoideoscopy reveal colonic polyposis (Gardner's syndrome). The most striking observation was, however, that up to 80% of the affected patients (compared with less than 5% in the normal control population, P less than 0.05) had multiple minor bone anomalies demonstrable by x-ray screening of the mandible, chest, and long bones. We suggest that a generalized (inherited or mutant) defect in growth regulation of connective tissue is the most important underlying cause for the DT. However, the other factors, including hormonal effects, trauma, and pregnancy contribute to the growth behavior of the tumor.