Both techniques are used for the purpose of hair loss evaluation Trichogram: Semi invasive method in which hair plucked from the scalp are microscopally  examined & provides information about the state of proximal end of hair shaft & distal end. Therefore it is a record of different phases of hair cycle. Useful tool for clinical evaluation, diagnosis & monitoring of treatment response. Trichoscan: Non invasive method Gives a magnified view of hair & scalp skin. It estimates hair density & hair thickness.