The triple differential cross section for electron impact ionization of helium in the special geometry of coplanar large energy loss and close to minimum momentum transfer are calculated by use of BBK model and modified BBK model. The structure of the cross section is discussed.The results of the present work are compared with current experimental data. It is found that both BBK and modified BBK models are in good agreement with the experimental results of binary-to-recoil peak ratio and their angular distribution.