Daily Archives: July 4, 2019

B lines do not always indicate pulmonary edema

Diffuse B-line pattern can be seen in pulmonary edema of various causes, interstitial pneumonia and diffuse parenchymal lung disease (e.g. fibrosis). Whether you are dealing with pulmonary edema or fibrosis largely depends on the clinical context. However, findings such as irregular, fragmented pleural line, sub pleural abnormalities appearing as small hypoechoic areas and nonhomogeneous distribution of B-lines favor fibrosis. On the other hand, “focal” B-line pattern may be seen in pneumonia, atelectasis, pulmonary contusion, pulmonary embolism, pleural disease and malignancy.

The following loops were obtained from upper anterior zones on each side (R/L). While they show B-line pattern, the lower lung zones were normal and the patient was breathing comfortably on room air. This is a patient with interstitial lung disease and the B-line pattern represents fibrotic process. Also note that the pleural line is irregular.

Ureteral jets

The intravesical ureteral jets, or the bladder jets represent the sonographic appearance of discrete boluses of urine entering the bladder, better detected using color Doppler. They are thought to result from autonomic and pressure dependent calyceal and ureteral peristalses.

Most healthy people have a ureteric jet frequency of 2 or more per minute on either side. Absence of ureteric jets during 10 minutes of observation in the steady diuresis phase may indicate complete ureteral obstruction, and the ureteric jet frequency of less than 2 per minute may indicate partial obstruction. In addition, jets may be absent in cases with poor renal plasma flow, or impaired unilateral renal circulation, such as in the case of renal cell carcinoma complicated with renal vein occlusion from tumor invasion or tumor thromboembolism.

However, their practical utility is not well established. In one study, urologists and radiologists disagreed on both the necessity for evaluating ureteral jets and their clinical relevance. In summary, if you see strong jets on both sides, it’s good and if you don’t, it doesn’t mean much unless you have suspicion for unilateral ureteral obstruction and there is no jet on that side after you ‘patiently’ monitored for at least 10 minutes.