One of the most common films among Upper Cervical Techniques is the Nasium. Learning to take one properly is an art, but here are some guidelines to taking an acceptable Nasium film.

When analyzing the nasium film, especially when employing a technic that involves the use of the skull divider (cephlocentroscope) such as NUCCA, Orthospinology, etc., it is extremely important that the film be taken with a minimum of head rotation -- 1/8 of an inch, or less.
Why?

Because on its A -- P axis, the skull is an elliptical object. Therefore, a slight amount of head rotation will cause significant distortion. Distortion of the radiographic shadows causes an illusion. If you have distortion due to poor X-ray placement, you are seeing something that is false, and you are developing false information about the case. As a result of this, you will lose control of your ability to get that sick person well. You may get decent results on a certain number of cases, but you have lost control of the consistency of results, which is necessary to build a large UC practice.

The following are factors to take into consideration when determining whether a nasium film has been taken accurately enough to provide a reliable analysis:


MAJORS
(these are the most reliable anatomical landmarks when judging the nasium film)
Comparison of lateral canthi (lateral aspect of the orbits) to the lateral aspect of the skull
Comparison of inner skull lines
Comparison of intersection of mandibles and mastoid processes
Comparison of widths of mastoids

MINORS
(these are less reliable because of inherent anatomical variables)
Nasal septum -- where it vertically intersects with the odontoid process
Comparison of lateral margins of the nasal cavity where they lie in relationship to the lateral masses
Comparison of zygomatic arches
Comparison of widths of ramuses of mandible


We will be glad to answer any questions regarding the above majors and minors, or any question in general on the nasium film.

Next -- methods for comparison of pre- and post- nasium films for evaluation of adjustment accuracy.