Yes. I had sinusitis and an attack of ON when I had it done the first time. Hard to say what it was due to -- well, probably both! Both inflammation and infection. I didn't get it run again until 2 weeks ago (over a month after my MS dx)and the sed rate was normal next time. So this is good news in that the tests show there's something going on in your body, just not what! Regardless of what the MRI shows, the blood work will have to be repeated at a certain point.