Rule Out As A Clinical Indication For Imaging Test

Rule out is sometimes placed as a clinical indication for a test by ordering providers.  This can be problematic because rule out may not be covered by insurance.  This is also not helpful to the radiologist reading the exam.  The radiologist needs a clinical indication to provide the best read possible.

What are some clinical indications?

Clinical indications for an imaging test may consist of symptoms, physical exam findings, an abnormal prior imaging test, or some other relevant history.  These are most helpful because they are more likely to be covered by the insurance company and allow the radiologist to focus on what’s most important.

For example, if the symptoms are right lower abdominal pain on a CT of the abdomen, the radiologist will be sure to look carefully at all the structures in this region of the abdomen.  An appendix which is a bit dilated in the presence of right lower quadrant abdominal pain may mean early appendicitis rather then normal anatomical variation.  Therefore having a history of right lower abdominal pain helps provide a more clinically relevant reading.

The radiologist already looks at every corner of every scan.  He will rule out important conditions which need treatment anyways. It goes without saying.  He will find a relevant history and reason for the exam much more helpful.

Rule out as an exam indication often forces the radiologist to spend extra time looking for the reason why the exam was ordered.  This may require a call to the ordering provider or a search through the records.  This will take him away from reading cases on sick patients who are waiting for treatment.

Rule Out Does not provide the real reason for the exam

Rule out may not provide the real reason why the exam was ordered.  Rule out PE or pulmonary embolism for a chest CTA may not tell the radiologist that the patient has chest pain and that other causes must be looked for like an aortic dissection or pneumothorax. Fortunately, the radiologist will look at every corner of the scan and rule out any important conditions.

Rule out also focuses on one condition when multiple causes for the patients symptoms may be present on any scan.   While the patient may not have a pulmonary embolism, he may have a pneumothorax or collapsed lung.  Therefore, rule out narrows the focus too much on one condition.

Rule out is a sometimes used clinical indication.  Rule out does not really give the reason for the exam being ordered.  It does not help the radiologist focus on anatomy which may be responsible for the patients symptoms.  It often forces the radiologist to find the real reason for the exam which takes him away from reading exams on other sick patients.