What is your diagnosis? Osteolytic lesion involving the distal portion of the diaphysis of the left femur: osteosarcoma.
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Biomedical subjects
Publications and source records attributed to D J Huber.
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Magnetic resonance imaging (MRI) has become a powerful diagnostic tool for the evaluation of the painful shoulder in general and of the diseased rotator cuff in particular. MRI evaluates cuff disease in terms of tendon morphology and pathologic signal alterations within diseased cuff tendons. Additionally, MRI displays important pathoanatomic changes of the coracoacromial arch which are predisposing factors for the development of shoulder impingement syndrome and cuff disease. The accuracy of MRI in diagnosing small rotator cuff tears and in assessing the integrity of the labral-ligamentous complex is improved by the intraarticular injection of a suitable contrast agent. In the preoperative assessment of patients with cuff disease, MR arthrography enhances the staging of the disease and allows a more confident exclusion of concomitant lesions of the shoulder joint.
We report the time-dependent magnetic resonance imaging (MRI) changes that resulted from an intramuscular injection of a commonly-used pediatric sedation regiment ("DPT"). These changes at the site of injection consist of a focal abnormality characterized by a slight increase in signal intensity on T1 weighted images and markedly increased signal intensity on T2 weighted images. Alterations in signal are detectable almost immediately after the injection and progress over the first 31 hours. This abnormality, which could be mistaken for real disease, persists up to 36 days following injection.
A case of interruption of both the superior and infrahepatic inferior vena cava with portal continuation of the systemic venous return is described. This unusual abnormality is probably acquired and represents the result of earlier, silent thrombosis of the venae cavae. Magnetic resonance imaging provided valuable anatomic information supplementing venography.
The proton NMR relaxation times of lung tissue were determined in a rabbit model of acute and evolving pulmonary hemorrhage (PH). Pure PH was simulated by injecting blood into a single lobe using endobronchial catheterization. In vitro spectroscopic measurements of T1 and T2 were made and total water content was determined on lung samples that were excised at regular intervals. T1 and T2 were markedly longer in lungs with acute PH than in normal lungs (T1: 818 +/- 44 vs. 643 +/- 4 msec; T2 164.0 +/- 16.3 vs. 88.1 +/- 3.4 msec). Within the first 24 hours, evolving PH was characterized by a rapid and progressive decrease in T1 (-50%) and T2 (-57%). Up to seven days after the instillation of blood, the T1 (450 +/- 43 msec) and T2 (69.7 +/- 1.9 msec) of lung with modeled PH remained below values of normal lung. The observed shortening of the relaxation times of lung disease with PH was closely paralleled by a decrease in tissue water content.
Magnetic resonance (MR) images of the shoulders of a healthy volunteer were obtained in axial, sagittal, and coronal orientations using a 0.5-T imaging system. Multiple high-resolution spin-echo images were generated using an off-center zoom technique and a specially designed surface coil. Several anatomic structures, including the rotator cuff, long biceps tendon, articular capsule, muscles, and bones, were visualized. The coronal and sagittal views were the most useful for demonstrating the rotator cuff. MR imaging has potential as a new non-invasive tool for the evaluation of the shoulder region.
Nuclear magnetic resonance spectroscopy was used to study the effect of chronic hypoxia on both right (RV) and left ventricular and septal (LV + S) muscle. Rats in the hypoxic group, kept in a hypobaric chamber at 1/2 atm pressure for 2 weeks, developed right, but not left, ventricular hypertrophy (p less than 0.001). Tissues were studied within 2.5 h of return to air. T1 and T2 relaxation times of RV, LV + S and thigh muscle (Th) from hypoxic and control rats were compared. The T2 value distinguished hypoxic from control RV (p less than 0.002), but not hypoxic from control LV + S or Th, indicating that the change in relaxation time reflects cellular hypertrophy, and not hypoxemia. For hypoxic rats only the T2 value distinguished each muscle type: RV from LV + S (p less than 0.009), RV from Th (p less than 0.001) and LV + S from Th (p less than 0001). The T1 value did not identify either the hypoxic or control group or the type of muscle. Percent water content was similar for all tissues. For hypoxic RV, T2 correlated with the percent water content (r = 0.89; p less than 0.01). The sensitivity of T2 to the cellular changes associated with hypoxic RV hypertrophy could provide a means of detecting right ventricular hypertrophy.
The purpose of this study was to establish the proton NMR relaxation times of collapsed but otherwise normal lung tissue and to determine whether an inflammatory process within a collapsed lung can be detected by alterations in relaxation times. The lungs of three groups of rabbits were studied: group A (n = 7) had a sterile collapse of one lung for two days. The two other groups also had one lung collapsed, but with bacterial (group B, n = 6) or chemically induced (group C; n = 6) pneumonitis superimposed. The contralateral lung, which was acutely deflated at the time of thoracotomy, served as a control in each animal. T1, T2 and the total water content were measured on freshly excised lung samples. In group A, there was no significant difference in T1 (606 +/- 14* ms vs. 595 +/- 18 ms;* = SEM) or T2 (80.6 +/- 1.7 ms vs. 78.4 +/- 2.6 ms) between the collapsed and the control lung tissue. In each animal in groups B and C, T2 was longer in the collapsed lung with superimposed pneumonitis than in the control lung tissue (group B: 116.8 +/- 6.9 ms vs. 82.9 +/- 1.8 ms, P less than .001; group C: 120.5 +/- 5.9 ms vs. 86.0 +/- 1.5 ms, P less than .001). T1 changes were similar, but less marked. There was a linear relationship between the relaxation times and the total water content of the lung samples (T1:r = 0.87; T2:r = 0.91). It is concluded that proton NMR may have a potential in detecting disease such as inflammation in collapsed lung tissue based on differences in relaxation parameters compared with normal lung areas.
The ability of proton NMR relaxation times to detect cardiac allograft rejection was studied in an inbred rat heterotopic cardiac transplantation model. Hearts from 25 Lewis X Brown Norway F1 hybrid rats were anastomosed to the abdominal aorta and vena cava of Lewis recipients; 25 Lewis donor hearts served as isograft controls. Groups of five allografts and five isografts were harvested daily between two and six days post-transplant. The relaxation times T1 and T2 of the transplanted hearts were determined in vitro with a 10 MHz spectrometer. T1 and T2 values in allografts did not differ significantly from those in isografts at days 2 and 3 post-transplant. However, at days 4, 5, and 6 T1 and T2 of the allografts were significantly prolonged. This finding correlated with an elevation in tissue water content and the onset of rejection as determined histologically. An additional 21 allografts, treated with cyclosporine, were studied in the same way from four to more than 100 days post-transplant. T1 and T2 values of these treated allografts did not change significantly during the observation period and were similar to the relaxation values obtained in the isografts at days 2 to 6. These data suggest that serial measurements of myocardial T1 and T2 may be useful in detecting acute cardiac allograft rejection and monitoring the effect of antirejection treatment.
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Two cases of puerperal thrombophlebitis of the ovarian veins are described and the literature is reviewed. By means of computer tomography, it has become possible for the first time to make the diagnosis of this little-known and frequently missed condition by a non-invasive method. The patient is spared complicated angiographic procedures and possibly also surgery. The typical CT findings consist of: a) a thickened adnexa, b) a circular lesion extending from the adnexa to the hilum of the kidney, c) an obstructed ureter and c) an enlarged uterus.
The potential of ungated computed tomography (CT) to detect and quantify myocardial infarctions was assessed in 10 dogs. Twenty-seven in vivo CT examinations were performed at various time intervals (1 hr-20 days) after coronary artery occlusion. After intravenous contrast administration, CT delineated the infarcted myocardium in all 27 studies. The CT-determined infarct volume before sacrifice was closely correlated (r = 0.98) with the postmortem infarct weight. Delayed accumulation of iodinated contrast material in the infarct was seen in all 22 examinations performed 3 1/2 hr or longer postocclusion. The dynamics of contrast material accumulation and disappearance from normal and ischemic myocardium were also assessed. Presently available CT scanning without gating can noninvasively detect and quantify myocardial infarctions of various sizes and ages in living animals and can evaluate contrast dynamics whose time course is greater than a single circulation time.