Paranasal sinuses and facial bones (lateral view)

The lateral paranasal sinuses and facial bones view is a nonangled lateral radiograph showcasing the facial bones (i.e. mandible, maxilla, zygoma, nasal, and lacrimal bone) and paranasal sinuses.

Indications

This view is useful in assessing any inflammatory processes or fractures to the facial bones, orbits, and paranasal sinuses. In instances of facial trauma, carrying out this view using a horizontal beam can be beneficial in assessing fluid-filled sinus cavities. It is also an important view for localizing foreign bodies in the trauma setting.

Patient position

• rest the lateral aspect of the patient's head (with the side of interest) against the image detector
• adjust the head into a true lateral position, with the midsagittal plane (Figure 1) parallel to the image detector
• for patient's comfort, adjust the patient's body into an oblique position

Technical factors

• lateral projection
• centering point
  • zygoma (cheek prominence), midway between outer canthus and the external auditory meatus (EAM)
• collimation
  • superior to include frontal sinus
  • inferior to include chin (especially important to include soft tissue to assess for foreign body or air in a trauma setting)
  • anterior to include skin margins
  • posterior to the EAM
• orientation  
  • landscape
• detector size
  • 24 cm x 30 cm
• exposure
  • 70-80 kVp
  • 20-25 mAs
• SID
  • 100 cm
• grid
  • no

Image technical evaluation

• sella turcica in profile
• temporomandibular joints are superimposed

Practical points

• remove earrings, glasses, piercings, and dentures to avoid artifact obscuring important pathology
• encourage patients to raise their chin to prevent superimposing the mandibular angle over the anterior cervical spine
• to ensure true lateral, the floor of the anterior cranial fossa should be superimposed