CPC was widely used and favored for many decades to access unruptured intracranial aneurysms at the anterior circulation.
8)9) However, it has some notable disadvantages to consider as suggested by Herneniemi et al. These drawbacks include excessive drilling of the skull base, especially in the temporal region and the sphenoid wing, chances of cerebro-spinal fluid (CSF) leak, which can often lead to infection, optic or oculomotor nerve lesions, and possible injury of the upper branch of the facial nerve.
3) In addition, epidural hematoma may be caused by CPC.
3) Therefore, keyhole approaches such as supraorbital eyebrow incision approach, mini-pterional were introduced as an alternative, however, they have a limited operative working angle.
2)4)7) Among them, FLC was determined to be the best, due to its advantages including shorter skin incision, smaller craniotomy, no alteration of temporalis muscle, which prevents temporalis muscle atrophy, and less complication such as postoperative epidural hematoma due to CSF leak.
3) In addition, the size of the craniotomy is absolutely sufficient to reach the whole anterior part of the Circle of Willis, sellar, suprasellar legion and also the anterior part of the basilar artery if it is located superiorly from the posterior clinoid process (
Fig. 2).
3) However, some limitations were also reported. FLC offers less exposure of certain lesions that need to be exposed from a more lateral (temporal) perspective: posterior communicating artery aneurysms pointing posteriorly, anterior choroidal artery aneurysms, middle cerebral artery (MCA) aneurysms, and lower positioned basilar tip artery aneurysms.
1)3) However, in our study, five out of 15 patients had posterior communicating artery aneurysms, which were all in the posterior direction.
Again, temporalis muscle atrophy is an aesthetic and functional complication of pterional craniotomy, which can delay patients' rapid recovery or deter them from returning to their previous occupations.
5) The main factors causing muscle atrophy are 1) denervation, 2) loss of blood supply, 3) inappropriate muscle tension and 4) muscle fiber injury.
6) When using FLC, the temporalis muscle is not manipulated during surgery, which not only shortens the operation time, but also discourages development of temporalis muscle atrophy. In this study, post-operative aesthetic outcome was proven to be significantly better in the FLC group than in the CPC group.