On Wed, 24 Aug 2011 14:06:16 -0400, Gray, Joyce <firstname.lastname@example.org> wrote:
UARS has still not gained as much recognition as it should. Our medical director, Dr. CN Reddy, is actually exceptional at the recognition and treatment of UARS.
I nearly didn't bother to make an appointment, as I haven't a lot of energy and I didn't have much reason to expect a positive outcome, but receiving this reply was very encouraging. So I came to your sleep center.
I was a little surprised that there wasn't a Pes sensor involved in my sleep study, but I'd read on PubMed about nasal cannulas being used to diagnose UARS by looking at the pressure waveform for indications of airflow obstruction. It's actually rather obvious once you know what to look for. I've attached a small image as an example, a sample from my own recording of my respiration during my sleep. The way that the normally semi-sinusoidal waveform becomes clipped on the top indicates restricted airflow on inhalation, indicating the presence of the "upper airway resistance" in "upper airway resistance syndrome." Then, after arousal (which I have verified with EEG), the waveform goes back to being semi-sinusoidal. Indeed, it's so easy to spot, one wonders why doctors ever resorted to using a Pes sensor, as it certainly doesn't sound as if one would be comfortable at all.
Here are a couple of free full-text articles I found on PubMed if you care to read about it:
http://www.ncbi.nlm.nih.gov/pubmed/10767242 -- Quote: "...inspiratory flow contour analysis has been shown to accurately identify changes in upper airway resistance. The shape of a normal inspiratory flow vs time signal is rounded or sinusoidal. A flattening or plateau of this morphology implies flow limitation, which is characterized by a nonlinear relationship between airflow and driving pressure secondary to increased airway resistance."
http://www.ncbi.nlm.nih.gov/pubmed/9603124 -- The third image in this article shows a waveform that looks remarkably similar to the image I've attached, which is from a recording of my own respiration during my sleep. Thus you can certainly see why I believe I have UARS.
I brought with me a printout of my respiration recording and showed it to Dr. Reddy. He seemed to have no idea that the flattened waveforms indicate anything at all. Instead he only saw smaller respiration waveforms interrupted with normal breathing and concluded it to simply be periodic breathing. So, rather than recognize it as UARS, Dr. Reddy instead concluded that I awoke 46 times and slept only 53% of the night for apparently no reason whatsoever.
Without a Pes sensor, and without knowledge of what those clipped waveforms indicate, I fail to see how Dr. Reddy can diagnose UARS at all, let alone be exceptional at it.
Anyway, I'm sure you didn't mean to be dishonest in your initial response. You, and indeed everyone I met at the sleep center, seem to care a lot. I can't even fault Dr. Reddy, as I've done enough research on the subject myself to realize that the odds are against me to ever have this diagnosed. The history of sleep research has unfortunately set things up in such a way that the symptoms of UARS are nearly by definition non-clinical. However, this whole experience has consumed time, money, and energy I didn't really have, something I was trying to avoid with my initial inquiry. So, I must say, I am rather disappointed.