see Transcallosal interhemispheric approach.
a) anterior transcallosal: good visualization of both walls of the third ventricle; risk of bilateral fornicial damage
b) posterior transcallosal: allows approach to quadrigeminal plate or pineal region;risk of damage to deep veins.
A plethora of surgical strategies have been described to reach deep-seated lesions situated within the third ventricle including the Rosenfeld, or transcallosal anterior interfoniceal approach.