High-resolution computed tomographic (HRCT) scans and chest radiographs were obtained in 23 patients with progressive systemic sclerosis (PSS) to assess the diagnostic merits of HRCT compared with chest radiography in detecting interstitial lung involvement in these patients. HRCT scans showed interstitial disease in 21 patients (91%). The most frequent finding was the so-called subpleural lines, which were demonstrated in 17 patients (74%). Honeycombing was seen in seven patients (30%), while parenchymal bands were seen in six patients (26%). Chest radiographs, on the other hand, showed definite interstitial opacification patterns in only nine patients (39%); six patients (26%) had equivocal reticular areas of attenuation, while eight patients (35%) had normal chest radiographs. Thus, HRCT is much more sensitive than chest radiography when assessing minimal interstitial lung involvement in patients with PSS.

To evaluate the histopathologic changes influencing Doppler measurements of the resistive index (RI) in renal arteries in renal parenchymal diseases, 68 kidneys in 34 consecutive patients with various forms of renal parenchymal diseases were studied by duplex Doppler ultrasound (duplex US) immediately before percutaneous renal biopsy. The RI, renal length, and renal cortical echogenicity were correlated with the amount of glomerular, interstitial, and vascular changes graded on a scale from 0 to 100. The renal vascular resistance and therefore the RI are significantly correlated with the prevalence of arteriolosclerosis, glomerular sclerosis, arteriosclerosis, edema, and focal interstitial fibrosis. There was no significant difference of the RI in five groups of different renal parenchymal diseases. Of 34 patients, 24 presented with an RI less than 0.7, which was thought to be within the normal range so far. Additionally, the RI increases as the patient's age increases, due to higher incidence of arteriosclerosis. Of our patients, 44% presented with normal cortical echogenicity. Quantitative duplex US using the RI does not reliably distinguish different types of renal medical disorders.

Ultrasound (US) proved highly effective for detection, localization, and delineation of enlarged lymph nodes of the neck. Infiltration of adjacent structures, specifically the common, internal, and external carotid arteries, and the neck muscles was reliably demonstrated. Benign and malignant lymph node enlargement could not be differentiated. US examinations changed the operative course of 56% of patients studied. In 41%, a more radical operative procedure was performed than was previously planned; in 14%, US demonstrated inoperability. Small-parts US is a very useful adjunct to current imaging techniques of cervical lymph node disease.

The effect of heart rate on Doppler measurements of the resistive index (RI) in renal arteries was studied in eight patients by varying paced heart rate to eliminate intrinsic and extrinsic factors influencing renal vascular resistance. A Doppler spectrum was obtained in renal segmental arteries. The RI was calculated at increasing heart rates from 70 to 120 beats per minute. There was a statistically significant decrease in RI with increasing heart rate (heart rate of 70: RI = 0.7 +/- 0.06; heart rate of 120: RI = 0.57 +/- 0.06; P less than .001), while blood pressure and cardiac output remained constant. To overcome this source of variance, the observed RI can be corrected for heart rate by using the following regression equation. For a heart rate of 80 beats per minute, corrected RI = observed RI - 0.0026(80 - observed heart rate). In interpreting the RI in renal allograft examinations, the actual heart rate of a patient must be taken into account. However, the clinical significance of standardizing the RI for heart rate requires further investigation.