Clinical indication:
Fracture, mastoiditis, tumor
Region:
Mastoid process, mastoid air cells
Patient’s Position:
Ask the patient to lie in prone position.
Place the patient’s head in true lateral position.
The inter-orbital line lies at right angle with the cassette.
The auricle of the ear near the film is folded forward.
Cassette:
Size: 8’’x10’’ Orientation: Landscape
FFD/SID:
100cm
Central ray:
The central ray is directed at an angle of 30° towards the feet. The central ray enters the skull above the ear at parietal region and passes through external auditory meatus proximal to film.
Grid:
Yes
Respiration:
Not related
Exposure factors:
70-80kVp 16-20mAs
Collimation:
Include all structures of temporal bone around mastoid process.