Airway Bifurcation Model Input Page

by

Dong Youb Lee

Seong Suk Park

George Ban-Weiss

Anthony Wexler

Although airway bifurcations are quite complicated, simplified typical bifurcations are characterized by a limited number of parameters. Visualizing such bifurcations can help researchers and students understand their shape, variability and development.

We have developed analytical expressions that describe airway bifurcations, although they may apply also to other bifurcations such as vessels or nerves. The procedure here is that the user enters target geometric properties of the bifurcation on this web page, we calculate the shape of the bifurcation, and display it in 3D on your browser. With a free plug-in, any browser can view 3D geometries. You can obtain such plug-ins free from Cosmo or Cortona. You must have a VRML compatible 3D plug-in, such as Cortona or Cosmo, in your browser to view the output from this web site. Your computer must have a fast web connection since these models contain about 3MB of data. Finally your computer must have lots of memory and be quite fast to store and manipulate the model.

There are a few parameters that characterize a bifurcating geometry. They are defined in the figure above. Angles are in units of degrees. Lengths are in arbitrary units, since everything can be scaled up or down as needed, but the values recommended below produce something that is a good size for viewing.

Parent Airway Parameters

The parent airway is assumed to be a straight cylinder that precedes the transition to the bifurcation itself. Describe the properties of the parent airway diameter and length.

Diameter:
Straight Section Length:

Offspring Parameters

Each offspring is assumed to be a curved section followed by a straight section. The curved section is a torus (donut), starting just after the carina, with a given diameter, continuing for a given subtended angle, and having a given radius of curvature. The straight section has a given length.

Right Diameter:
Right Subtended Angle:
Right Radius of Curvature:
Right Straight Section Length:

Left Diameter:
Left Subtended Angle:
Left Radius of Curvature:
Left Straight Section Length:

Carina Parameters

The carina has properties that describe how the parent daughter transition occurs. At this point, the only parameter is the radius of curvature of the carinal crease.

Carina Radius of Curvature:

Displaying the Results

If you have completed all the parameters above, the form is ready to submit. We will take your parameters, calculate the bifurcation shape and display the results. Be patient -- the calculations are fast but the download may take some time depending on the speed of your web connection.

To submit your calculation, click here:

Research described on this website was supported in part by Philip Morris USA Inc.