9.05: Zone C3 – Superior Medial Region
YOUR ASSIGNMENT FOR THIS LESSON
✅ Step #1: Review all content below.
✅ Step #2: Image the C3 zone on your own with your ultrasond, and using the checklist provided on this page, check off all key structures to be identified in this location.
TRANSDUCER POSITION AT C3
STANDARD C3 ORIENTATION:
TRANSVERSE & LONGITUDINAL
The intersection of the vertical line from medial canthus to the horizontal line from the superior alar groove is the location of C3.
- Like the other zones that involve the nose, use a lot of gel in this area. By filling the contour between the nose and cheek with gel you will capture better images and be able to apply less pressure which will maintain optimal visualization of the underlying anatomy.
- Identify the periosteum of the maxillary bone, then identify two hypoechoic bands in both the longitudinal and transverse positions. These bands will correspond to the LLSAN muscle and LLS muscle.
EXAMPLE OF TRANSVERSE IMAGE ACQUIRED AT C3
ANATOMICAL LEGEND FOR C3 LOCATION IN TRANSVERSE
EXAMPLE OF LONGITUDINAL IMAGE ACQUIRED AT C3
ANATOMICAL LEGEND FOR C3 LOCATION IN LONGITUDINAL
KEY VESSELS IN THE REGION
DOPPLER IMAGES ACQUIRED AT C3 OF KEY VESSELS
- The angular artery lives up to its name and travels in an angular direction. Angulating your probe where the superior aspect is more medial in the longitudinal position will allow you to see a bigger slice of the angular artery simultaneously.