If the opening of the sinuses are blocked and that is the cause of your continued sinus problem, then it is unlikely that the nasal washes are going to have much effect. Having a CT scan of the sinuses is a good way to visualize the openings of all of the sinuses. I can understand your fears for major sinus surgery. However, if the openings are blocked, there is a much less invasive procedure to try to open these sinuses. I would suggest speaking with your ENT about a CT of the sinuses as the next step and discussing options on the basis of the findings.