Dehydration & Obesity Correction – Explanation

Only lean body mass (approximated by Ideal Body Weight, IBW) contains meaningful water. Excess Weight is mostly adipose tissue, which has low water content. Dehydration therefore affects lean and obese patients differently.

The attenuation factor used is:

F = 1 / (1 + (Excess Weight / IBW))

Adjusted dehydration-related TBV change:

ΔTBV_dehyd,adj = F × ΔTBV_grid