Surgical Anatomy of Supratentorial Midline Lesions

FIGURE 5. Branches of the pericallosal artery that supply the corpus callosum. A, a photograph showing the body of the corpus callosum ( B)
after an interhemispheric approach. Forceps retract the left pericallosal artery to show the origin of the callosal artery( arrow), which arises
from the left A4 segment and directly supplies the superficial surface of the corpus callosum in the midline, without giving branches to the
depths of the callosal sulcus. B, the medial surface of the right cerebral hemisphere. After partial removal of the cingulate gyrus ( CG), the
callosal sulcus is revealed. Forceps retract the right pericallosal artery. The cingulocallosal arteries ( arrows) arise from the inferolateral aspect
of the pericallosal artery, run laterally into the callosal sulcus, and form a portion of the pericallosal pial plexus. B, body of corpus callosum;
SP, septum pellucidum. C, the medial surface of the right cerebral hemisphere. After partial removal of the cingulate gyrus( CG), the callosal
sulcus is revealed. The pericallosal artery courses in the cingulate sulcus ( CS). The long callosal artery ( arrow) arises from the pericallosal
artery, supplies the body ( B) and splenium(S) of the corpus callosum. It is the major contributor to the pericallosal pial plexus ( PP).CN,
caudate nucleus; F, fornix;G, genu of corpus callosum. D, the medial surface of the right cerebral hemisphere. After partial removal of the
cingulate gyrus (CG), the callosal sulcus is revealed. Forceps retract the A5 segment of the pericallosal artery. The posterior extension ( arrow)
of the A5 segment follows a corkscrew-like course within the callosal sulcus at the splenium( S) and forms the dense portion of the pericallosal
pial plexus (PP). B, body of corpus callosum; CP, choroid plexus; F, fornix.
FIGURE 10. Lateral projection of a left vertebral artery angiogram showing the distal type of posterior pericallosal artery ( black arrow), which
runs to the splenium ( S) and divides into two main branches. The superior branch ( white arrowhead) courses within the callosal sulcus with a
characteristic tortuousity and anastomoses with the posterior extension of the A5 segment. The inferior branch ( black arrowhead) runs
anteriorly and anastomoses with the branches of the medial posterior choroidal artery( white arrow) in the tela choroidea of the third ventricle .
In other instances where one or more of the A3 through A5 segments coursed in the cingulate sulcus and were, therefore, not involved with
the corpus callosum, the prominent blood supply to the affected portions of the corpus callosum was provided by the median callosal artery, the
long callosal artery, the opposite hemisphere's pericallosal artery, or any combination of these arteries. When the A5 segment coursed in the
cingulate sulcus (35%), these arteries subsequently anastomosed with the posterior pericallosal artery in the splenial region (Fig. 5C).