In cases that continue to resist treatment or medication, endoscopic sinus surgery may be an option. For this procedure, the doctor uses an endoscope, a thin, flexible tube with an attached light, to explore your sinus passages. Then, depending on the source of obstruction, the doctor may use various instruments to remove tissue or remove away a polyp that's causing nasal blockage. Enlarging a narrow sinus opening also may be an option to promote drainage. ..For DNS septoplasty is a good option...