Gastroesophageal Reflux Testing

Gastroesophageal Reflux Disease (GERD) is a digestive disorder that can affect people of all ages, and occurs when acidic stomach juices, food or fluid reverse flows from the stomach into the oesophagus.

GERD immediately comes to mind when symptoms such as heartburn and regurgitation are mentioned, but it is not often thought of for symptoms such as chronic cough, sore throat, voice hoarseness or recurrent ear infections.

Lime Radiology offers a bulk billed, non-invasive gastroesophageal reflux test. Unlike other diagnostic tests for reflux that are limited to detecting reflux in the oesophagus, this test also detects reflux contamination throughout the head, neck and lungs.

Contamination of reflux throughout the head and neck can be the cause of ear and sinusitis infections, sore throat and difficulty swallowing. Reflux can also irritate the airways and be aspirated into the lungs causing chronic cough, recurring chest infections, bronchitis, or pneumonia.

Test Process

You are required to fast for 4 hours prior to your examination.

Please do not have anything to eat, drink, smoke or chew during the fasting period. All medications (including prescribed reflux medication) must be taken on the day of your examination prior to the 4 hour fasting period.

This test is performed in two stages.

Stage One

Upon arrival to clinic, the Nuclear Medicine technician will give you 20ml of an over the counter liquid anti-acid (GastroGel, Gaviscon, or equivilent) followed by approximately 50mL of water with a small dose of Technetium, and another 50mL of water to flush and clear the mouth of the tracer. 35 minutes of imaging will commence after consuming the water.

Dynamic images are taken from the mouth to the stomach in the upright and supine position. These images are then analysed with special software to indicate the frequency and amplitude of reflux contaminating the upper oesophagus and pharynx/laryngopharynx.


Following part one, there will be a 90 minute break. During this time you must continue to fast, however you may leave the department. The Nuclear Medicine Technologist will advise you of when you need to return to the department.

Stage Two

Following a 90-minute break, a further 25 minutes of imaging will commence. A study of the head, neck and chest will be performed to detect any aspiration of refluxate into the head and neck structures (including the laryngopharynx) and lungs.

Our Nuclear Medicine Physician will review the images and issue a report. Once completed, the report will be sent electronically to your referring health professional.


This is a simple scintigraphic study which visualises in real time backflow of stomach contents into the oesophagus, head, neck and lungs. This is the first test which has been able to see reflux in the head and neck structures.

The test itself is very simple, a small amount of a radioactive tracer is swallowed diluted in water it is both odourless and tasteless. The path of the water is then images by the camera in real time in an upright and lying position. 90 minutes later detailed 360- degree images are performed of the head, neck, and lung regions. This provides both functional and structural information called SPECT/CT.

This is the first medical test that allows us to visualise the refluxed fluid in sites that have been suspected of being injured by reflux.

Your GP or specialist may refer you for this test to investigate if reflux could be the cause of, or contributing to, one or more of the following conditions:

  • Cough
  • Chest pain
  • Throat clearing
  • Difficulty swallowing
  • Difficulty breathing
  • Recurrent chest, throat and/or ear infections
  • Sinusitis
  • Pneumonia
  • Bronchitis
  • New or worsening asthma
  • Disrupted sleep

The indications for the test are basically any chronic atypical symptoms, consistent with those of 'silent reflux', and for which an alternate explanation cannot be found. 

Silent reflux is quite common and affects approximately 40 to 50% of patients who have gastro-oesophageal reflux disease.  It is referred to as 'silent reflux' because it does not present with the classical symptoms of reflux, being heartburn, lump in the throat and regurgitation.  There is in fact nothing silent about the symptomatology which is often called atypical.  These symptoms range from chronic cough, recurrent sore throats, loss of voice, persistent throat clearing, chest pain, choking, wheezing and shortness of breath.  

This test is not advocated for diagnosing simple reflux which presents with classic and obvious symptoms, such as heartburn and regurgitation, as this can be managed clinically without testing.

  • Your original request form
  • Medicare and any Government concession pension or health care cards

The test does involve exposure to a small amount of radiation. The entire test, radioisotope and CT exposure is less than an interstate flight and a fraction of a chest x-ray.

Please allow up to three hours for the test to be completed. The first part of the test will take 45 minutes to one hour. There will then be a two hour break before part two of the test commences. Part two of the test will take 45 minutes. You are free to leave the department for the two hour break between part one and part two.

Your results will be sent to your doctor electronically within five working days.

The test is BULK BILLED for Medicare card holders.

Historically, GORD has been diagnosed using pH monitoring, fluoroscopy or endoscopy.

pH monitoring is performed off therapy. Standard test preparation is to cease anti-reflux therapy for the 3 days prior to the test. This causes a rebound acid effect, and the stomach produces more acid. Although this test is 50-80% sensitive & 77–100% specific in the presence of heartburn & regurgitation, it is limited to oesophageal disease only, particularly the lower oesophagus. This test is expensive, invasive, and may be poorly tolerated by patients.

Endoscopy is effective as an anatomical diagnostic tool, but has a poor sensitivity for GORD (less than 30%) and is limited to detecting reflux disease that is severe enough to damage the oesophagus.

Fluoroscopy or Barium Swallow is insensitive and has a high radiation burden and only demonstrates oesophageal disease.

The Gastroesophageal Reflux Test provides an effective, bulk billed, non-invasive screening tool for oesophageal disease, LPR and lung aspiration, detecting contamination throughout the maxillary sinuses, throat, middle ears, laryngopharynx, airways and lungs. This test is 90% sensitive, detecting both acid and non-acid reflux and is well-tolerated by patients.