Figure 12. Two-part pterional approach.

A) Marking starts at the superior rim of the zygomatic arch, 1 cm anterior to the tragus, and extends to the midline.

B) The scalp flap is reflected over the orbit to expose the superficial temporal fascia (inferior to STL) and frontal pericranium (superior to STL). STL, superior temporal line.

C) The scalp flap is further retracted to show the suprafascial fat pad. Incisions should not extend beyond the dotted line to avoid injuring the temporal branches of facial nerve. Br, branches.

D) The frontal pericranium and both layers of the temporal fascia are elevated together to maintain their continuity over the STL. A musculo-fascial cuff is left along the STL. ITL, inferior temporal line; STL, superior temporal line.

E) The temporalis muscle is dissected via a T-shaped incision to produce two muscle flaps.

F) The first burr hole is drilled behind the MacCarty keyhole towards the anterior cranial fossa. The second burr hole is placed in squamous portion of the temporal bone.

G) V-shaped craniotomy is performed around the lateral sphenoid wing to create two bone pieces.

H) The second bone cut is made with a footplate attachment passing under the lesser wing of sphenoid. Br, branch; MMA, middle meningeal artery.

I) Result of the two-part pterional craniotomy that shows the expanded subfrontal space.