X-RAY OF SKULL
Region: skull, facial bone
Pathology: fracture of skull and facial bone, inflammatory condition of frontal sinus and ethmoid sinus
SID: 100 cm (40 inches)
Central Ray: beam directed at the nasion with 15˚ caudal angulation
Respiration: suspended
Position
1. The patient is placed in an erect position, in a sitting position, or in a prone position.
2. Align the midsagittal plane (MSP) of head to the vertical axis crossing the center of the image receptor (IR).
3. Flex the cervical vertebrae forward enough to align the orbitomeatal line (OML) perpendicular to the IR.
4. Lean forehead and nose gently on the IR to place the nasion at the center of the IR.
Evaluation
1. Petrous ridge is projected in lower 1/3 of orbits above the inferior orbital margin.
2. Bilateral petrous ridges should be symmetric and the skull should be projected with no rotation.
3. Frontal bone, ethmoid sinus, nasal septum, crista galli, etc should be clearly visible.
kVp-75, mAs-20
Tip
1. Generally it is usual to project 15° caudad to nasion.
2. Project perpendicularly to nasion to see frontal bone well. For superior orbital fissure, project 20°~25° caudad and 25°~30° caudad for foramen rotundum.
3. For prone position, if assistance instruments are used like pillow under the chest, it is easy to bend cervical vertebrae so that orbitomeatal line (OML) can be perpendicular to image receptor (IR).
4. For patient who is uncomfortable with bending cervical vertebrae, adjust skull to make Inferior OrbitoMeatal line (IOML) be perpendicular to IR and project 8° caudad to nasion.
5. If it is impossible to adjust OML or IOML to be perpendicular to IR, do not adapt the position by force. Adjust Central X-ray to be parallel with IOML to project.
6. It is hard to maintain the pose for patient; the inspection must be done in a short time.
X-Ray Skull P/A View position:
Region: skull, facial bone
Pathology: fracture of skull and facial bone, inflammatory condition of frontal sinus and ethmoid sinus
SID: 100 cm (40 inches)
Central Ray: beam directed at the nasion with 15˚ caudal angulation
Respiration: suspended
Position
1. The patient is placed in an erect position, in a sitting position, or in a prone position.
2. Align the midsagittal plane (MSP) of head to the vertical axis crossing the center of the image receptor (IR).
3. Flex the cervical vertebrae forward enough to align the orbitomeatal line (OML) perpendicular to the IR.
4. Lean forehead and nose gently on the IR to place the nasion at the center of the IR.
Evaluation
1. Petrous ridge is projected in lower 1/3 of orbits above the inferior orbital margin.
2. Bilateral petrous ridges should be symmetric and the skull should be projected with no rotation.
3. Frontal bone, ethmoid sinus, nasal septum, crista galli, etc should be clearly visible.
kVp-75, mAs-20
Tip
1. Generally it is usual to project 15° caudad to nasion.
2. Project perpendicularly to nasion to see frontal bone well. For superior orbital fissure, project 20°~25° caudad and 25°~30° caudad for foramen rotundum.
3. For prone position, if assistance instruments are used like pillow under the chest, it is easy to bend cervical vertebrae so that orbitomeatal line (OML) can be perpendicular to image receptor (IR).
4. For patient who is uncomfortable with bending cervical vertebrae, adjust skull to make Inferior OrbitoMeatal line (IOML) be perpendicular to IR and project 8° caudad to nasion.
5. If it is impossible to adjust OML or IOML to be perpendicular to IR, do not adapt the position by force. Adjust Central X-ray to be parallel with IOML to project.
6. It is hard to maintain the pose for patient; the inspection must be done in a short time.
X-Ray Skull Lateral View
Skull Lateral
Region: skull, sella turcica, greater wing of sphenoid
Pathology: fracture of skull, deformation of sella turcica, inflammatory condition of paranasal sinus, paget's disease
IR Size: 24 × 30 cm (10 × 12 inch)
SID: 100 cm (40 inches)
Central Ray: perpendicular beam directed at the point 4 cm (1.5 inches) above the external auditory meatus (EAM) with 0°angulation
Respiration: suspended
Position:
1. The patient is either in an erect
position or in a semi-prone position.
2. Align the Inferior orbitomeatal
line (IOML) parallel to the horizontal axis of image receptor (IR).
3. Adjust the head to align the Interpapillary Line (IPL) perpendicular to the
IR and to align the midsagittal plane (MSP) parallel to the IR.
4. Place the point 4 cm above the external
auditory meatus at the center of IR.
5. Maintain the true lateral position of the head, by placing the patient's ear
tightly on the IR.
Collimation: Include the entire structure of skulls between parietal region and mandible.
Evaluation
1. Without the rotation, the
superimposition of the sella
turcica with anterior
clinoid process, greater
wing of sphenoid, mandibular
rami, extra
auditory meatus and temporomandibular
joint should be observed.
2. The sella turcica should not be rotated and the floor of sella turcica
should be shown as a line not a plane.
3. Without the tilt, the superimposition of superior
orbital margins should be observed.
kVp:70, mAs:16
Tip
1. When patient cannot pose semi-prone
position, place patient in supine position and lean temporal
bone on image receptor (IR) to make true lateral position. In this
case, projecting horizontally is considered.
2. Semi-prone position is an uncomfortable position; it helps the position to
use assistance instruments like pillow or sponge to support cervical region.
3. It is hard to maintain the pose for patient; the inspection must be done in
a short time.
