Facial Bones Flashcards
What are the projections for facial bones?
-Lateral
-Parietoacanthial (Water’s Method)
-Caldwell (PA)
What size film is used for lateral facial bones?
8 x 10 lengthwise
How is the patient positioned for a lateral facial bones?
-Semiprone position or seated obliquely before a vertical grid device
-Patient in a comfortable position (arms in comfortable position and adjust shoulders to lie in the same transverse plane)
How is the position of the part for a lateral facial bone?
-Interpupillary line perpendicular to the film
-Adjust the flexion of the patient’s neck so that the OML is equal with the transverse axis of the film
-Place the radiolucent pad under the side of the mandible to prevent rotation
-Immobilize head
What are the breathing instructions for lateral facial bones?
suspended respiration
Where is the CR for a lateral facial bones?
perpendicular to the midpoint of the film entering the lateral surface of the zygoma
What structures are shown in a lateral facial bones?
lateral image of the bones of the face is demonstrated, with the right and left sides superimposed
What is the evaluation criteria for lateral facial bones?
-All facial bones in their entirety with the zygoma in the center
-Almost perfectly superimposed mandibular rami
-Superimposed orbital roofs
-No rotation of sella turcica
What film size is used for a Parietoacanthial (Water’s) for facial bones?
8 x 10 lengthwise
What is the position of the patient for a Parietoacanthial (Water’s) for facial bones?
-Prone or seated upright position
-Place patient in comfortable position
What is the position of the part for a Parietoacanthial (Water’s) for facial bones?
-Center the median sagittal plane of the patient’s head to the midline of the grid; and rest it on the tip of the extended chin
-The average patient’s nose will be 3/4 in away from the grid device
-Extend the neck so that the OML forms a 37 degree angle with the plane of the film
-The Mentomeatal line will be approx. perpendicular to the film plane
-Adjust the head so the median sagittal plane is perpendicular to the plane of the plane
-Immobilize the head
What are the breathing instructions of a Parietoacanthial (Water’s) of the facial bones?
suspended respiration
Where is the CR for a Parietoacanthial (Water’s) for facial bones?
perpendicular to exit the acanthion
What structures are shown in a Parietoacanthial (Water’s) for a facial bone?
Orbits, maxillae & zygomatic arches
What is the evaluation criteria for a Parietoacanthial (Water’s) for facial bones?
-Equal distance between lateral border of the skull and orbit on each side
-Petrous ridges should be seen just below maxillary sinuses
-Orbits, zygomatic bones and maxilla should be well demonstrated
-If not enough extension of neck, petrous ridges will superimpose lower maxillary sinuses
-If too much extension of neck, petrous ridges will be seen considerably below the maxillary sinuses
What film size is used for Caldwell (PA) for facial bones?
8 x 10 lengthwise
What is the position of the patient for Caldwell (PA) for facial bones?
Erect, seated or prone on table
What is the position of the part for Caldwell (PA) for facial bones?
-Place patient’s forehead and nose on table or grid device
-Align midsagittal plane perpendicular to plane of film and in midline of table or grid device
-Adjust head to place OML perpendicular to plane of film
Where is the CR for Caldwell (PA) for facial bones?
-15-degrees caudad to exit the nasion
What are the breathing instructions for Caldwell (PA) for facial bones?
suspend respiration for exposure
What is the evaluation criteria for Caldwell (PA) for facial bones?
-Frontal sinuses and frontal bone should be well demonstrated
-Petrous bones should fill lower one third of orbits
-Distance from lateral orbital margin to lateral margin of skull should be equal on both sides
-Anterior ethmoidal air cells should be seen
-Superior orbital fissures should be visualized
