<p> How To Tell If A Skull Radiograph is Acceptable!</p><p>PA or AP</p><p>1. Are the exposure factors correct? (frontal bone should be properly penetrated without excessive density at lateral borders of skull, proper contrast)</p><p>2. Is the entire cranial perimeter included? (all of mandible is not necessary- that is another exam!)</p><p>3. Is there rotation? (distance from lateral border of skull to lateral border of orbit should be equal on both sides)</p><p>4. Is there tilt? (Head leaning to left or right side)</p><p>5. Proper extension/flexion? (petrous ridges should fill orbit)</p><p>PA AXIAL (Caldwell) (This is just a PA with 15 degree caudad angle of CR)</p><p>Same criteria as PA or AP above except #5 -petrous ridges should lie in lower 1/3 of orbit!</p><p>Lateral</p><p>1. Are exposure factors correct? (Proper contrast and density)</p><p>2. Is the whole cranium on image? (all of mandible is not necessary!)</p><p>3. Is there rotation? (Rami of mandible should be superimposed, TMJ Superimposed, sella in profile) EAM,& mastoids superimosed</p><p>4. Is there tilt? (Orbital roofs must be superimposed, sella in profile)</p><p>5. Proper extension/Flexion? (Mandible should not overlap C-spine) (technically, IOML should be parallel with long-axis of image) Page 2 How to tell if the Radiograph is Acceptable</p><p>Towne (AP Axial)</p><p>1. Are the exposure factors correct?</p><p>2. Is the entire cranium on image? (Again, Mandible not necessary!)</p><p>3. Rotation? (Distance from lateral border of skull to lateral border of foramen magnum should be equal on both sides. Petrous pyramids should be symmetrical)</p><p>4. Tilt? (Does head look like its cocked to one side or the other?</p><p>5. Flex/Extension? (Dorsum sellae and post. Clinoid processes should be seen in foramen magnum. Too flexed, C-1 is seen in foramen, too extended- don’t see sellae and processes in foramen, may not even see foramen magnum!)</p><p>SMV (Basal)</p><p>1. Are exposure factors correct?</p><p>2. Is entire cranium on image?</p><p>3. Rotation? (Midsagital plane should be parallel with lengthwise axis of film)</p><p>4. Tilt? (Distance from lateral border of skull to mand. Condyles should be equal on both sides)</p><p>5. Flex/extention? (too flexed- mental protuberance won’t super-impose anterior frontal bone. Too extended-never have this problem on real pt., on phantom-mental protuburance will over-extend frontal bone.</p><p>6/7/08</p>