Figure 2.
(A) With the anterior transsylvian-transinsular approach, the head position, skin incision (dashed line), and craniotomy (solid line) are the same as a for an MCA aneurysm. (B) A standard pterional craniotomy with drilling of the sphenoid wing exposes the sphenoidal portion of the Sylvian fissure. (C) A wide Sylvian fissure split exposes the MCA bifurcation, the insular segments (M2), the limen insulae, and short gyri. (D) A small cortical incision is needed to reach lesions not on the insular surface. Abbreviations: F = frontal lobe; T = temporal lobe; Mal = malformation; SV = Sylvian vein; M1 = sphenoidal segment of MCA; M3 = opercular segment of MCA; M4 = cortical segment of MCA.