The pterional craniotomy: tips and tricks

Abstract

The frontotemporosphenoidal craniotomy, usually denominated pterional craniotomy, was first described by Yasargil in 1975 and is one of the earliest landmarks of the advents of microneurosurgery [1][2][3] . This approach enables, specifically, the exposure of the entire frontoparietal operculum 4,5 , the opening of the entire sylvian fissure 6,7 and all anterior cisterns of the encephalon base 2,5 , which makes both the pterional craniotomy and the transylvian approach the widest used techniques in today's neurosurgery practice.Over the past decades, the pterional craniotomy has undergone a systematization modified by several authors, what also gave rise to more extended types of craniotomies 8,9 . Among then, the supraorbital craniotomy 10 and the orbitofrontozygomatic craniotomy 10-13 stands out. This review offered a detailed description of the technique we use nowadays for this procedure, with modifications arising from its extensive use since its initial proposal, seeking to optimize all its stages, the access and opening of the cisterns, as well as minimize brain retraction. DESCRIPTION OF PROCEDUREPositioning -the patient should be placed supine, with the shoulder at the edge of the surgical table in a neutral position, and head and neck remain suspended after removal of the head support. The head should be secured by a three-pin skull fixation devise (Mayfield or Sugita model) and must be maintained above the level of the right atrium to facilitate venous return. In order to avoid the head holder position to hinder the surgeon' s procedure, the ipsilateral pin of the operative field should be set on the mastoid region, while the two contralateral pins should be on the contralateral superior temporal line, above the temporal muscle, that should not be transfixed. The pin corresponding to the ipsilateral mastoid and the most anterior one corresponding to the contralateral superior temporal line must be in parallel position to prevent any head movement, especially during future traction of cranial wraps made with the aid of fish-hooks.There is a sequence of five movements for the positioning of the head: traction, lifting, deflection, rotation and torsion. ABSTRACTThis review intended to describe in a didactic and practical manner the frontotemporosphenoidal craniotomy, which is usually known as pterional craniotomy and constitute the cranial approach mostly utilized in the modern neurosurgery. This is, then, basically a descriptive text, divided according to the main stages involved in this procedure, and describes with details how the authors currently perform this craniotomy.Key words: craniotomy, microsurgery, neurosurgery. RESUMOA presente revisão visou descrever de forma didática e prática a realização da craniotomia frontotemporoesfenoidal, usualmente denominada pterional, que constitui a craniotomia mais utilizada na prática neurocirúrgica atual. Trata-se, portanto, de um texto fundamentalmente descritivo, dividido conforme as principais etapas envolvidas na realização desse procedimento, que mostr...

Orbitozygomatic craniotomy in three pieces: tips and tricks

“…The placement of wet gauze and later traction of the scalp flap can spare the use of haemostatic clips and specific staples for this purpose 8,16,17,18 .…”

“…The interfacial dissection of the temporalis muscle, as originally described by Yasargil, is specifically intended to preserve the front temporal branch of the facial nerve and reduce postoperative cosmetic changes resulting from the surgical wound 8,16 . We had four patients (8,1%) who evolved with temporary (about two months) frontal branch facial nerve palsy.…”

“…Pterional craniotomy, popularized by Yasargil in 1976, is the most used surgical route in neurosurgery 6,7 . It exposes transylvian and lateral subfrontal views 8,9 . In 1961, Drake introduced the subtemporal approach 10,11 which offers a lateral view of the interpenducular fossa by retracting the temporal lobe superiorly.…”

The far-lateral craniotomy: tips and tricks

“…After the positioning and trichotomy, the marking of the skin incision is done, so that its two endings form an imaginary straight line that adequately simulate the separation of the skin flap and the consequent bone exposure 4,5,6 . Initially, inion, asterion, C2 spinous process and mastoid apex should be marked.…”

“…The dural incision should be initiated using a scalpel blade #11, and continued with Metzenbaum scissors 4,5,6 . With these opening procedures, the dural flap can be reflected medially.…”