For the analytical purposes of creating simple and easy to understand velocity graphs, I divided the model image results into thirds: “Lower third”, “Middle third” and “Upper third”.
How to read the velocity scale:
Depending on the flow rate and model specifics, the correct scale (shown above) needs to be chosen to best show all details in each model. The images above for a 5L/minute flow rate are set to 0-200cm/second. If I were run a 10L flow rate and display results in the same 200 scale, most of the image would be red, thus the need to choose an appropriate scale setting to best show the full dynamic range. Whenever making side by side comparisons here I always use the same scale settings.
A Key to understanding these results is that the left side was normal prior to surgery. There were no pre surgical complaints with the left side so I consider the 2006 pre-surgery left side (right in images) results to be a “normal baseline” to compare against going forward from here. These left side pre-surgical results compare closely to Wexler’s study for that of a “normal nose”. This is also handy as it removes any question as to my modeling process as the result is an “apples to apples” comparison.
Most sources agree that the majority of the air we breathe travels through the middle of the nose in an arc like fashion. The book “Functional Reconstructive Nasal Surgery” by (Huizing/de Groot), states that “The inspiratory air stream takes a higher curved course and the expiratory airstream follows the lower passage way”. “After traversing the valve area, the air stream takes a more horizontal course. It hits the heads of the middle and inferior turbinates, enters the middle and to a lesser extent the inferior nasal passages and finally curved downward”. (emphasis added) Their pathways for IN and OUT are borrowed and shown below:
Starting with the supposition that the main inspiratory path is an arc like path through the middle and upper portion of the nose we can examine changes in airflow distribution as a direct result of these two surgeries.