Abstract
The interhemispheric approach after frontal craniotomy is a fundamental technique in microneurosurgery. However, it is quite difficult to employ without injuring the pia mater or pial capillary vessels, if the operator does not have precise and stable microsurgical technique. Itoh et al. described an interhemispheric approach in 1983 in which they recommended a 3-step procedure for the dissection of the interhemispheric approach. In the first step, the pericallosal cistern should be exposed; second, the arachnoid trabeculae between the cingulate gyrus and anterior part of the gyrus rectus should be dissected; and third, the bilateral residual gyrus rectus should be separated, exposing the aneurysm. A meticulous technique is required in the second and third steps to visualize the arachnoid trabeculae between the pia mater and vessels because of the compact microanatomical structures. The author describes technical suggestions for the effective use of microscissors and a cerebral retractor.
