Normal bone marrow in the sacrum of young adults: differences between the sexes seen on chemical-shift MR imaging.

OBJECTIVE: Age-related changes in the distribution of fatty and nonfatty bone marrow in the pelvis and femur are well recognized. However, mapping not only of age-related MR appearance of normal bone marrow but also of potential variations in females versus males is necessary to differentiate normal findings from marrow disease. Accordingly, we studied possible sex-related differences in the MR imaging appearance of sacral bone marrow in young adults. SUBJECTS AND METHODS: A population of 21 healthy men and 21 healthy women (17-42 years old) was prospectively studied with chemical-shift pulse sequences. MR imaging (1.5 T) of the sacrum was done with frequency-selective fat images (SENEX [selective nonexcitation] 300/27) and water images (SENEX 1000/27) by using an elliptical surface coil. Two independent observers compared the signal intensity of sacral marrow with the signal of fatty tissue planes adjacent to the sacrum (fat images) and the signal of gluteus muscle (water images). T2 relaxation times were estimated by using a two-parametric monoexponential fit on SENEX 1000/27 and SENEX 1000/54 images. RESULTS: In both sexes, fat MR images showed a higher fat content and greater heterogeneity in the bone marrow of the lateral masses than in the vertebral bodies of the sacrum (p < .05). Yellow marrow in the lateral masses of the sacrum appeared brighter in men than in women (p < .05). The heterogeneity of fatty marrow did not differ significantly between the sexes. On water MR images, the signal intensity of the sacrum was higher in women (p < .05). T2 relaxation times were longer in nonfatty marrow with a high water signal intensity (41.8 +/- 5.5 msec versus 33.4 +/- 2.6 msec p < .01). CONCLUSION: Our findings show that the normal appearance of the sacral bone marrow depicted on chemical-shift MR imaging differs between young men and women. Awareness of these differences is important to avoid misinterpretation of normal MR findings seen in patients in this age group.

Neuroimaging in alcoholism: CT and MRI results and clinical correlates.

For more than a century we have known the deleterious effects of alcohol on the brain regions surrounding the third ventricle and on the cerebellum. But it was only recently that we gained clearer evidence that the cortex is affected as well. Our imaging studies show that brain shrinkage is at least partially reversible once abstinence is maintained. They confirm results obtained in different laboratories from all over the world. Although our data contradict the rehydration hypothesis and thus lend credence to the idea of regeneration and neuroplasticity, the nature of reversibility is still a matter of debate.

[The value of the supine chest x-ray with digital luminescence radiography in relation to the experience of the observer. A ROC analysis in CT-validated cases]. / Wertigkeit der Thoraxliegendaufnahme mit der Digitalen Lumineszenzradiographie (DLR) in Abhängigkeit von der Erfahrung des Untersuchers. Eine ROC-Analyse in CT-validierten Fällen.

The aim of the present study was to evaluate supine chest radiographs obtained by DLR for the diagnosis of pleural and parenchymatous changes and to compare the accuracy of observers in relation to their experience. 50 examinations, which had been checked by CT, were chosen. The images were examined by 7 doctors (2 non-radiologists, 5 radiologists). Our experience indicates that DLR has high specificity but low sensitivity for the diagnosis of a pneumothorax but relatively high sensitivity and low specificity for other changes (pleural effusions, atelectases and other intrapulmonary opacities). The area under the ROC curve averaged over the 7 rater was similar for these 4 entities. There were marked differences between the observers; the radiologists were considerably better than the non-radiologists. Altogether, the diagnostic value of single DLR examinations was relatively low. In indeterminate cases, additional diagnostic methods should, therefore, be used.

[The monitor findings of digitalized conventional wrist x-rays]. / Monitorbefundung digitalisierter konventioneller Handwurzelaufnahmen.

The study aimed at proving the reliability of monitor systems with the matrix of 1024 x 768 for the detection of scaphoid fractures compared to conventional X-ray. Moreover, we were interested in the significance of procedures of digital imaging post processing, depending in particular on the experience of investigators. 5 investigators with different levels of experience analysed 57 X-rays of the wrist. They compared conventional X-rays with images on a high screen monitor system after the digitalisation of these X-rays by a CCD-scanner and analysed untreated and treated images. A 5-point scale ROC analysis was used for evaluation. The analysis covered a total of 1740 evaluations. The untreated images seen on the monitor system proved slightly better than conventional X-rays. Post-processing has no evident advantage over untreated images. Differing levels of experience had no effect whatsoever on the identification of findings.

[CT and HR-CT in the diagnosis of pulmonary complications of bone marrow transplantation]. / CT und HR-CT in der Diagnostik pulmonaler Komplikationen bei Knochenmarktransplantation.

The aim of this prospective study was to compare conventional and high resolution CT for demonstrating pulmonary complications. 23 patients treated by bone marrow transplantation were included in the study between December 1990 and August 1991. These patients were examined radiologically at regular intervals following the transplants. In 9 patients lung changes were detected by CT: there were pneumonic infiltrates, including one CMV pneumonia, two cases of mild parenchymal fibrosis, two cases of extensive lung fibrosis and one of miliary tuberculosis. The advantages and disadvantages of conventional and high resolution techniques are discussed in relation to our findings.

[The value of the AMBER system in demonstrating intrathoracic space-occupying lesions. A comparative ROC study of the AMBER and conventional technics for postero-anterior views of the thorax. Advanced Multiple Beam Equalization Radiography]. / Stellenwert des AMBER-Systems beim Nachweis von intrathorakalen Raumforderungen. Vergleichende ROC-Studie der AMBER- und der konventionellen Technik bei Thorax-p.a.-Ubersichtsaufnahmen.

Since October 1991 the AMBER technique has been used for the diagnosis of chest diseases in about 4,000 patients. The ability of this technique, compared with conventional methods, for demonstrating intrathoracic masses on p.a. views has been assessed. Amongst the patients there were 43 with coin lesions, 18 with hilar and 33 with mediastinal masses. ROC analysis showed the AMBER technique to be superior in demonstrating coin lesions (AMBER 0.92, conventional 0.85) and mediastinal masses (AMBER 0.89, conventional 0.73). There was a small, statistically not significant, disadvantage in the AMBER technique for demonstrating hilar masses (AMBER 0.80, conventional 0.84).