While Loops and Converge Criteria for pseudo steady state model

Hello,

I am attempting to create a series of simulations whose aim it is to examine the influence of my model's physics on the models geometry. What I have is a vascular geometry , which has a certain parameter (vessel diameter) which varies according to the concentration of various chemical species in my computational domain. Instead of using a transient solver I instead choose to run a series of psuedo steady state simulations. I create some sort of stimulus, a change in the consumption of one of the chemical species in the models, and this triggers a cascade of reactions which ultimately cause the diameter of the vessel to change. The convergence criteria that I wish to use is the concentration of one of the chemical species. I've tried this with average values, but would rather use the matrix of concentrations in a manner similar to how Comsol would do this. I'm trying this with the help of Matlab, but was wondering if it would be possible to only use Comsol alone and perhaps a segregated solver?

Let me know if anyone has any insight in how to deal with such a problem and perhaps tutorials which I can use in order to figure out my issues.

Thanks

Pat