Estimating Patient Size From a Single Radiograph
Estimating Patient Size From a Single Radiograph
A computational model has been created to estimate the abdominal depth of a patient from a
 single x-ray image. The model has been tested using phantoms and found to be accurate; this
 study aims to test the accuracy of the model with patients and in a clinical setting.

 This will be achieved by enrolling patient's who have already been referred for an
 anterior-posterior abdomen x-ray examination to the trial, taking a physical measurement of
 their anterior-posterior abdominal depth and then comparing this measured value with a value
 as estimated using the computational model based on the patient's x-ray image.
A non-commercial computational model has been developed in-house to estimate the patient's
 anterior-posterior or lateral depth using the radiographic image and the known exposure
 factors with which it was undertaken. This model has been tested using single composition
 phantoms and found to be accurate. If it was found to be accurate for real clinical
 examinations, this would automate the measurement of patient size and give institutions the
 estimate of patient size required for local paediatric patient dose audit. In turn, this
 would provide the national data required to propose national reference values for paediatric
 x-ray examinations, which would give all institutions an important comparator for their
 performance. This would lead to optimisation in those sites most requiring it; nationally,
 paediatric x-ray imaging would improve in time.

 This pilot study is necessary to determine if the computational model is accurate enough to
 be relied upon. Accuracy will be determined by comparing the estimate made by the
 computational model for each patient with an actual measurement of the patient's
 anterior-posterior abdomen depth made at the time of the examination.
Inclusion Criteria:

 -  Adult

 -  Referred to Ninewells Hospital for an anterior-posterior abdomen x-ray examination

 Exclusion Criteria:

 -  Patients unable to give consent

 -  Patients who have had a contrast injection in the previous 24 hours

 -  Patients suffering abdominal pain at the time of the examination