Hi, Noted your history of postnasal drip, coughing if not cleared and sinus mucositis with retention cysts on CBCT. I would advise you the following in such a situation: Nasal decongestant drops followed by plain water steam inhalation three to four times a day. Oral decongestant. Antihistamine orally. Oral steroids in taperning dosages, needs a valid prescription. All these measure will help you to get a proper results in three weeks. Repeat CBCT after three weeks of rigorous treatment and if the findings are still present you may need removal of the retention cysts as these are the cause of post nasal drip. At the same time you have to follow some rules: Avoid the allergens and factors, foods and beverages that instigate or enhance the problems. Avoid sudden temperature differences. Avoid blowing nose or clearing throat too hard. Rest of the additional treatment as per advise of your ENT Surgeon. I hope this answer helps you. Let me know if I can assist you further. Regards, Dr. T Chandrakant, ENT & General Surgeon