If you have R2013b you should use readtable() instead of xlsread(). It's so so much easier. Instead of all that nonsense of 3 cell arrays, which aren't even matched up as far as rows and columns go, you get a simple and intuitive "table" - which is a new variable class in R2013b that I encourage everyone to try.
ONCE YOU TRY readtable(), YOU'LL PROBABLY NEVER USE xlsread() EVER AGAIN.
Another use of the table is to use with regionprops() and struct2table() to create a table instead of an array of structures. I'll contact the Image Processing team to see if they can make a table an option directly instead of having to use struct2table.