Monthly Archives: August 2019

This jellyfish is not atelectasis!

Previously, we talked about atelectasis and pneumonic consolidations. Here is a unique case shared by Dr. Kylie Baker @kyliebaker888, where misdiagnosis could have lead to deleterious consequences.

A 70-year-old man with a history of substance abuse presented with left sided chest pain and presyncope. Right lung POCUS was normal and so was the left anterior scan. However, left posterior zone demonstrated anechoic pleural effusion and a mobile echogenic structure (***) that appeared to be an atelectatic lung vs. pneumonia (causing pleurisy) at first glance. Cardiac windows were difficult to obtain.

CT scan of the chest demonstrated ruptured thoracic aorta and left hemothorax, which means the echogenic structure on ultrasound was a blood clot and not lung tissue.

How to differentiate?

A blood clot appears homogeneous and does not have air bronchograms (dynamic or static) unlike the lung tissue. Moreover, there will not be any demonstrable blood flow within the structure. As mentioned before, pneumonia > atelectasis tends to be hyperemic. So, pay attention to detail.

Stone-In-Neck phenomenon

Stone-In-Neck or the ‘SIN’ sign is when you see an immobile stone lodged in the gallbladder neck, without any anechoic space between the neck and the stone. It is suggestive of cholecystitis even in the absence of other sonographic signs such as thickened gall bladder wall, Pericholecystic fluid, sonographic Murphy’s sign etc. One small study found that the sensitivity of this sign is 56.5% and the specificity 97% for cholecystitis.