Which ionization chamber should be used for a tangential projection of the intertubercular groove?

In performing a tangential projection of the intertubercular groove, the need for precision in exposure time and technique is significant due to the anatomical structures involved and the specificity of the projection. An ionization chamber, or Automatic Exposure Control (AEC), is designed to measure the radiation that passes through the patient and to terminate the exposure automatically when an adequate amount has been detected.

The tangential projection requires careful positioning and angling which can alter the path of the x-rays through the anatomy. This projection may not align well with standard AEC configurations, which are typically set to work effectively with more commonly used projections where the anatomy is positioned directly over the AEC chamber.

If a projection does not effectively utilize the AEC system, it can lead to inaccurate exposure times and image quality concerns, making it unreliable for this specific procedure. Additionally, the anatomy for this projection may not adequately cover any of the traditional cells of a standard AEC system, which would further complicate its use.

Therefore, because of the unique requirements of the tangential projection and the potential issues associated with AEC operation in this context, relying on an AEC for this projection would not be appropriate, which leads to the conclusion that it cannot be used with this projection