There are two major phases of an ACT Examination:
Patient Preparation
Patients are required to follow the ACT Pre-examination Protocol prior to the test. The protocol limits the patient's physical presentation and controls examination environment. These requirements have been established to maximize the accuracy of the test by eliminating various factors which could alter the thermal characteristics of the patient's face and neck.
Recording the Images
This procedure involves positioning the patient for three views and assuring the camera is properly prepared for capturing the images.
Adherence to a strict pre-examination protocol enhances the accuracy of the thermographic evaluation. Deviation from the protocol could result in misleading changes in the patient's thermal characteristics. To assure the integrity of the examination it is imperative that influences altering blood flow be avoided. The following summarizes the key points in preparing the patient for the examination:
Patient did not ingest alcohol, stimulants, etc., within 24-hours of the examination.
Patient did not smoke cigarettes nor had caffeine or hot/cold beverages within 2-hours of examination.
Serial examinations should always be performed at the same time of day.
Thermal equilibration is the process under which the patient's skin achieves thermal stability in a temperature-stabilized environment. Although sometimes required to increase the skin temperature, it is generally a cooling procedure. A minimum ten-minute period of thermal equilibration with the pre-examination and examination room(s) temperature(s) between 68°F - 72°F is absolutely essential to the accuracy of the CBT examination.
The ACT Examination requires three images: Left and right oblique views of the face and neck, and a frontal view capturing the area between the top of the forehead and the area just below the thyroid gland. The frontal view has the patient slightly tipping the head back such that the area over the thyroid is clearly visible.
It is essential to assure the patient's hair is not obstructing or obscuring any part of the face and neck, especially the areas over the auricular and temple regions. A surgical cap or equivalent is suggested.
The image recording procedure is relatively simple, but with minor constraints that must be adhered to.
The exact distance between the camera and the surface of the patient is a critical parameter for camera calibration, and small changes in camera-patient-distance are very important.
Small changes in distance may not be ignored. If the camera-patient-distance changes for each view, the camera is not calibrated and the ability to properly analyze the images is compromised.
Camera-patient-distance uncertainty can be minimized by employing specific foot positions for each view. As before, alignment is made to a line marking the stored camera-patient distance:
Important: The end position of the heels for the oblique views is with the heel of the rotated foot against the inside heel of the stationary foot. The patient's weight is supported on the stationary foot. The patient is standing relaxed in natural posture.
Note that for each position, the patient's foot/feet are aligned with the camera-patient-distance line.