What you describe must be a very disturbing situation and I can appreciate how your saying “it is ruining my life” is not an exaggeration. More X-rays are not the answer and “peri-bronchial thickening” is not a valid explanation. Establishing the cause of a chronic, severe cough is not always easy and, from your description, it appears that your doctors have exhausted their diagnostic capabilities. What you need and what I strongly recommend is a thorough diagnostic evaluation of your respiratory system and your upper gastrointestinal system by doctors who specialize in the diagnosis and treatment of chronic cough.
Such specialists are to be found in Cough Clinics at the majority of University Hospital Medical Centers; that is, associated with Medical Schools. Not knowing where you live, I cannot make specific recommendations but the following may be helpful.
Finding the cause(s) of chronic cough can be perplexing even for experts in this field but, with the advent of formal cough clinics, the rate of success has increased significantly in recent years. The best known of these is that directed by Dr. Richard Irwin and associates at the University of Massachusetts Medical Center in Worcester, Mass. But there are other high quality centers including the Mayo Clinic in Rochester Minnesota, the University of Michigan Medical Center at Ann Arbor, Michigan, and National Jewish Health (formerly National Jewish Medical and Research Center) in Denver, Colorado (disclaimer, I am a member of the Medical Staff at this institution).
Good luck
Thank you very much for your reply. Unfortunately I live in Australia. I intend to see a Respiratory Specialist in December. I hope I gat the help I need.