Sender: Michael Nowicki

I am a physician at the University of Mississippi. I am trying to compare the size of polyps (abnormal growth of tissue in the colon) between 2 groups of individuals. The department of pathology gives the size as length X width X depth - how do I calculate the volume? Polyps are nearly ovoid in shape.

I appreciate any help you can provide.

Sincerely:
Michael Nowicki

Michael,

If it is 'oval' meaning ellipsoid, then the appropriate volume formula is a modification of the volume of a sphere. In the terms you have been given, the volume of a sphere is

where all three measurements happen to be equal. For the ellisoid (oval) you stretch the 'length' - and that stretches the volume by the same ratio, then the width - and that also stretches the volume by the second ratio.
   The net result is STILL the formula

Walter

Go to Math Central