Pulmonary embolism after hip or knee replacement: postoperative changes on pulmonary scintigrams in asymptomatic patients

Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.     

Orbital dermoids: features on CT

The computed tomographic (CT) features of orbital dermoids were retrospectively reviewed in 17 patients; 15 of the lesions were proved histologically. On the basis of clinical and CT features, the tumors were classified as superficial or deep. All but one were extraconal in location. Seven lesions appeared cystic; only six showed typical fat density. The presence of a margin or rim, often partially calcified, was identified in ten lesions. Irregular scalloping of adjacent bone was a highly suggestive feature, occurring with 11 dermoids. Other bone changes, such as linear defects, thinning, or sclerosis, also occurred. Superficial dermoids showed less apparent bone changes. An extraconal orbital lesion associated with adjacent bone thinning or notching should raise the possibility of a dermoid, especially if a rim with calcification is seen. The appearance is pathognomonic if fat density is also present.     

Effacement of the fetal cisterna magna in association with myelomeningocele

The cisterna magna is effaced in association with myelomeningocele. The authors retrospectively investigated the size of the fetal cisterna magna as a predictor of fetal myelomeningocele in 67 pregnant women (17-38 menstrual weeks) referred for prenatal sonography because of an elevated serum alpha-fetoprotein level (n = 61) or a suspicion of fetal ventriculomegaly on previously obtained sonograms (n = 6). Twenty fetuses had myelomeningocele, 14 had isolated ventriculomegaly, and 33 were normal. A normal-sized cisterna magna (range, 4-9 mm in depth) was present in all normal fetuses. In 19 of 20 fetuses with myelomeningocele, the views of the posterior fossa were adequate, and in each of these the cisterna magna was effaced (n = 18) or very small (n = 1). The cisterna magna was effaced in five of 13 (38%) fetuses with isolated ventriculomegaly in whom the posterior fossa was adequately imaged. Although effacement of the cisterna magna is a nonspecific finding, the high negative predictive value of this sign is useful during routine screening of the fetal neural axis.     

Centrilobular emphysema: CT-pathologic correlation

Over a 5-year period, 25 patients who had undergone chest computed tomography (CT) died and were autopsied. Their lungs were fixed in the inflated state and were assessed for the presence and severity of centrilobular emphysema (CLE). Three radiologists independently evaluated the CT scans for nonperipheral low-attenuation areas, peripheral low-attenuation areas, pulmonary vascular pruning, pulmonary vascular distortion, and pulmonary density gradient. The CT criterion that best correlated with the presence and severity of CLE was the nonperipheral low-attenuation area. With this CT criterion, lung destruction was correctly identified in 13 of 15 cases. The absence of this criterion resulted in correct identification of eight of ten normal lungs. These preliminary data suggest that CLE can be reliably identified and quantified with current CT scanners.     

Effect of repeated sampling and prestimulation on saliva buffer capacity and flow rate values in children

Abstract— Great variations reported in the frequency distribution of buffer capacity values may partly be due to methodological differences in saliva sampling. In this study we wanted to see to what extent these variations are due to repetition and prestimulation. 9-yr-old schoolchildren ( n : 41, 23 girls and 18 boys), who had never had saliva samples taken before, participated in the present study. The repetition tests were carried out between 9 and 11 a.m. on three subsequent days. The effect of prestimulation was tested 4 days later with the same subjects. The buffer capacity of the samples was determined electrometrically immediately after sampling using the commercial Dentobuff-test. The intraindividual analysis revealed a significant increase in flow rate but not in buffer capacity along with repetition of the sampling. The analysis further showed that the buffer capacity of children accustomed to saliva sampling increased significantly through prestimulation of 1 min. The use of prestimulation resulted in substantial changes also in the frequency distribution of the buffer capacity values. Our results emphasize the importance of proper sampling conditions in saliva collection when screening children for high caries risk.     

Hodgkin disease: contributions of chest CT in the initial staging evaluation

Chest radiographs and chest computed tomography (CT) scans were compared in 203 patients with newly diagnosed Hodgkin disease. The incidence of positive findings was tabulated from six intrathoracic lymph node groups, lung parenchyma, pericardium, pleura, and chest wall. The discordant cases were assessed to determine impact on clinical management. The CT scans provided additional evidence of disease involvement, ranging from 0% to 15% at each of the designated anatomic sites. Treatment was altered in 9.4% of all patients (19 of 203), including 13.8% (nine of 65) of those undergoing radiation therapy alone and 8.2% (ten of 122) of those undergoing combined-modality treatment. We conclude that routine chest CT examinations are valuable in the clinical management of those patients for whom radiation therapy is planned.