Brief Answer:
Laryngopharyngeal Reflux

Detailed Answer:
Hello,
Thanks for choosing HealthcareMagic for your querY.
I ma a Gastroenterologist and would be addressing your query.
Have gone through your details and i appreciate your concerns.

As per your query answers are-

What you are describing as feeling lump in throat is a classical symptoms seen in history of patient with acid reflux.
Acid reflux into the pharynx, or back of the throat, can also cause atypical symptoms. Patient may feel as if they constantly have sore throat, or always need to clear your throat. Additionally, it may feel as if there is a lump in the back of your throat that won't go away(As in your case).

The term use to describe it better is silent reflux, also known as (LPR). The condition, which causes throat irritation Laryngopharyngeal Reflux and pain, is referred to as silent reflux because it often lacks the hallmark symptom of GERD and typical acid reflux – heartburn.

Tests that should be done on you are
Proton pump inhibitor test- a trial of proton pump inhibitors, which reduce the amount of acid secreted by the stomach. If your symptoms improve or disappear with medication then you most likely have LPR.

After that an Endoscopy can be planned to rule out the cause of acid reflux.Small camera would be used to see the throat.Tissue samples are usually taken to test in the laboratory for any evidence of chronic irritation, inflammation, infection, or abnormal cells.
Barium swallow-This test involves a series of X-rays of the upper gastrointestinal system, performed after a patient drinks a special barium solution. The contrast solution allows us to evaluate the digestive tract for structural problems that may be associated with LPR.In case there is any mass it would be apparent.

MRI of throat should be kept reserved. In case if any mass appears in above mentioned tests MRI can be done.
No MRI brain and Spinal; cord will not catch it.
Seperate MRI for throat will be done by radiologist.

Thank you.

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