Effect of Craniotomy on Temporalis Function

In contemporary neurosurgery, when performing a pterional craniotomy, neurosurgeons have been taught to cut through and detach the temporalis before drilling the skull to "turn a bone flap". While there are ways to turn a bone flap with the temporalis still attached (i.e., an "osteoplastic craniotomy"), this is thought to be slightly more time-consuming and is used less often in many centers. Additionally, there is a common misconception that osteoplastic craniotomy does not allow an equivalent view, although recent evidence suggests that the surgical exposure in the two approaches is no different. Aside from the extra time involved, we do not feel that leaving the temporalis attached to the bony calvarium disadvantages the patient in any fashion (and-in fact-may result in less post-operative morbidity). We are interested in this project because there is actually very little objective data regarding the morbidity people experience when the temporalis muscle is cut and mobilized prior to drilling the skull. If, in this study, we find that the group randomized to traditional pterional craniotomy experiences significantly more morbidity than the group randomized to osteoplastic craniotomy, this may justify conversion to an osteoplastic craniotomy in many or all instances. We wish to quantify the morbidity that is associated with the specific methods used to detach the temporalis muscle from the skull. Many variables regarding the way the temporalis is detached will be recorded and assessed in the group randomized to traditional pterional craniotomy. Additionally, many methods will be used to measure post-operative temporalis atrophy and/or dysfunction in the two randomized groups. After post-operative morbidity has been quantified, we plan to compare the traditional pterional group to the osteoplastic group and assess for significance.