I had a functional endoscopic sinus surgery last year. I highly recommend Dr. Catherine Picken at Washington ENT. She is one of the best doctors I have ever had, and the surgery went very well. It was well worth traveling to DC to see her. She will spend a tremendous amount of time with you, examining you and talking to you in detail about what she recommends and why. They have a facility in the building where they can do your MRI if necessary. My surgery involved all my sinus cavities (I had polyps that had about 90% of my sinus cavities blocked), so they used the computer guided technology.
Here's a link to info on that surgery:
http://www.washingtonent.com/tnendoscop.htm
Here's a link to Dr. Picken:
http://www.washingtonent.com/phybios.htm#picken
If you go w/ Dr. Picken and she recommends surgery, you will have a choice of hospitals. I don't recommend Georgetown - that place was a disaster for my surgery (Since I live so far from the hospital, Dr. Picken wanted me to spend the night then go home in the morning. They didn't have a bed for me, so I spent hours in the recovery room on a gurney. I have heard much better thnigs about Sibley. In fact, I had surgery at Sibley (about 8 years ago), and I thought it was a great hospital.
Let me know if you have any questions. Good luck!