Abstract
The operative field of the anterior interhemispheric approach depends on the frontopolar vein, height of the endofrontal eminence, and the lamina cribrosa. We measured the distances between the frontopolar vein and the nasion (F-N distance) and the frontopolar vein and the lamina cribrosa (F-C distance) in lateral view of both carotid angiograms (subtraction films) in 67 cases. The frontopolar vein drained bilaterally into the superior sagittal sinus at the frontal pole in 59 cases (88%). In the remaining 8 cases, the frontopolar vein entered into the well-developed frontal cortical vein instead of the superior sagittal sinus and drained into the superior sagittal sinus at the rolandic area. These configurations were found in 2 cases with both sides, in 3 with the right and in 3 with the left side. The F-N distance averaged 4.2cm (ranging from 3 to 6cm) and the F-C distance 5.3cm (ranging from 4 to 7cm). Before using the anterior interhemispheric approach, it is very important and necessary to know the relationship between the frontopolar vein and structures (the endofrontal eminence, the lamina cribrosa and nasion) of the anterior cranial fossa
