Ultrasound Quiz 1: Back to Basics

Welcome to the first iteration of Musig Mondays! Enjoy the quiz!

If you get an answer wrong, don't worry! There's a detailed explanation for each question (and if it's too much reading, just look at the words in bold).

Great Job! You were able to identify which scanning technique was being used!
The ultrasonographer who performed the scan is fanning their probe to view the entire heart.
The probe is placed below the xiphoid process (the caudal tip of the sternum (towards the feet)), pointing cephalad (towards the head). We call this view the Subxiphoid view.
The probe is held in the transverse position (the probe is perpendicular to the long axis of the patient)
In this view, fanning allows the ultrasonographer to scan the entire heart to rule out any pathology such as pericardial effusion or a hemopericardium.

At the end of the quiz there will be a list of scanning techniques with images.
Yes! Great job!
The right pleural space is being imaged. There are a few hints that can help us figure out what we're looking at:
1- A major hint is the curtain sign. Notice how the image gets concealed by what looks like a curtain. This occurs when the lung expands during inhalation which displaces the liver caudally (towards the feet) and distorts the image (because air disperses ultrasound waves and does not image well). Please note that in this case, while the lungs and rib cage are expanding and contracting with inhalation and exhalation respectively, the probe is not moving.

2- The big structure you see in the middle/ right field of the image is the liver, which is said to have a “starry night” appearance on ultrasound. This orients us to the right side of the patient. You cannot see the tip of the liver here; to see the liver tip you would have to slide more caudad (towards the feet/ the right field of the image). The structure caudal to the liver (on the right side of the image) is the kidney.

3- In the far field (the bottom of the image), you can see a hyperechoic (white) squiggly line underneath the liver. These are the thoracic vertebral bodies of the spine. It is not visible cephalad to the diaphragm (the hyperechoic parabolic line to the screen left of the liver) because of aerated lung tissue, as air scatters the ultrasound waves and distorts the image. However, if a patient has a pleural effusion (fluid cephalad to the diaphragm), the fluid will act as an acoustic window and allow us to see the spine continue up cephalad to the diaphragm. This is called a spine sign.
Great job! The patient has a collapsed lung, better get that fixed!
We see a lung point indicative of pneumothorax (collapsed lung).
With a linear probe in the longitudinal position, the ultrasonographer is scanning the lungs. The long hyperechoic line just above the moving tissue represents the two layers of the pleura separated by a potential space. In a normal lung, this line shimmers as the layers of pleura move against one another. On the screen left, we can see lung sliding.
However, notice that the sliding suddenly stops in the screen middle. This is called a lung point. Finding a non-physiological lung point is highly suggestive of a pneumothorax which is informed by the clinical picture.
The cardiac lung point and the liver lung point are two normal or ‘physiologic’ lung points that might confuse a junior scanner. Knowing your surface anatomy, scanning on the least-dependent part of the chest (most anterior point of the body where air will collect) and ruling out the presence of the heart or liver on the screen can help you avoid making this error.