Occipito-frontal View of Skull :

This projection allows the orbits to be checked for their equality of size, which is important in patients with proptosis. The floor of the hypophyseal fossa can be seen through the nasal cavity and this should be looked at closely if a pituitary tumour is suspected. Check the supraorbital fissure and the greater and lesser wings of sphenoid for any abnormality. Watch for vault fractures in the frontal region and for blowout fractures through the floor of the orbit. The nasal cavity, the medial wall of the maxillary antrum and the ethmoid air cells are well seen in this projection.

   Lateral View of Skull :

This is probably the most important of the skull views. There are several features which must be checked on this projection: the hypophyseal fossa, both for pituitary tumours and for the effects of raised intracranial pressure; the position of the pineal, if calcified; the width of the soft tissue shadow on the posterior aspect of the nasopharynx and oropharynx, and the posterior walls of the maxillary antra. Do not confuse vault fractures with vascular markings and suture lines. Look for other physiological calcification sites, e.g. habenular calcification (reverse C-shape), petroclinoid and interclinoid ligament calcification. The frontal, sphenoid and maxillary air sinuses are clearly visualized on this projection, as is the pterygopalatine fossa.

   30° Fronto-occipital View of Skull (Towne's Projection) :

This view shows the region of the foramen magnum, the occipital bone and the petrous ridges, which should be checked for any abnormality. Check for posterior vault fractures. See if the pineal or the choroid plexuses of the lateral ventricles are calcified and, if they are, check there is no midline shift. This view also demonstrates the zygomatic arch clearly.

   Submento-vertical View of Skull :

This projection is of the base of the skull. The sphenoid air sinus is well shown. The numerous exit foramina from the skull are easily identified. Look for enlargement of the foramen spinosum which can occur in vascular vault meningiomas with a large external carotid arterial supply. Check the petrous apex and the region of the jugular foramen. Check the middle ear and its ossicles. Identify the three bony lines which overlap anteriorly: the greater wing of the sphenoid, the posterior wall of the orbit and the posterior wall of the maxillary antrum.

   Occipito-mental and Occipito-frontal Views of Skull :

These two projections show the frontal and maxillary sinuses to their best advantage. The maxillary antrum is seen on the occipitomental view; in particular, the roof of the antrum, the floor of the orbit, is clearly visualized. The frontal sinus is seen on both views. Look for sinus abnormalities such as mucosal thickening and fluid levels. Also check for facial fractures. The infraorbital foramen and the foramen rotundum can be seen on these projections.

   Tomograms of the Internal Ear :

These tomograms demonstrate the anatomy more clearly than the plain films, and are essential when looking for small lesions such as fractures and congenital anomalies of the middle ear and temporal bone. High-quality tomography often of polycycloidal type together with 1 or 2 mm cuts are needed to show these minute structures. The crista transversalis separates the facial from the acoustic nerve and is an important landmark, as it disappears in intracanalicular acoustic neuromata.

   Lateral Soft Tissue Film of the Neck :

This film uses the natural air of the pharynx and larynx as contrast medium. The cartilages of the larynx are seen and undergo true ossification rather than calcification. The retropharyngeal space between the posterior wall of the trachea and the anterior border of the cervical spine should not exceed the AP diameter of one vertebral body. Note the following: the articulation of the thyroid and cricoid cartilages; the air in the ventricle of the larynx between the true and false cords; and the position of the larynx extending from C3 to C6. The pharynx can also be seen in its anatomical divisions of nasopharynx, above the soft palate, oropharynx between soft palate and base of tongue, and hypopharynx from base of tongue inferiorly.

   Lateral Soft Tissue Film of the Face :

The soft tissue projection of the face is mainly taken for nasal spine and nasal bone fractures; however, nasal fracture displacement is best visualized on an axial projection. This soft tissue view is also useful for assessment of dental occlusion or bite.