Reference: Raabe 2019
Approach | Positioning | Notes | Indications |
Medial subfrontal | Supine, neck flexed, head extended | Frontal bone flap extends to midline. Can also take orbital rim (cranio-orbital approach) | Unilateral tumor or vascular lesion in anterior cranial fossa |
Pterional (lateral frontotemporal) | Supine, ipsilateral shoulder elevated 30°, head rotated 30° | Extends anteriorly in a curvilinear manner toward supraorbital rim, details full approach (see image) | Anterior and middle cranial fossa lesions |
Orbito-zygomatic | Supine, ipsilateral shoulder elevated 30°, head rotated 30° | As pterional, plus en bloc removal of supraorbital rim, zygoma in second osteotomy | Anterior and middle cranial fossa lesions |
Extended middle fossa (Anterior petrectomy) | Supine, head turned contralateral to lesion side | Removal of petrous apex between foramen ovale and arcuate eminence, detailed osteotomies | Middle/posterior cranial fossa: Petrous apex, superior clival, anterior CPA lesions, posterior cavernous sinus, basilar artery and anterior brain stem |
Bifrontal | Supine, neck flexed, head extended | Zygomatic arch to zygomatic arch incision. May remove orbital bar (risk: trigeminocardiac reflex) | Bilateral anterior cranial fossa: midline tumors, large olfactory groove/planum sphenoidale/tuberculum sellae meningiomas, large craniopharyngiomas |
Interhemispheric | Supine, head slightly flexed or semilateral, head turned 90° w/ 45° vertex tilt | Bipartite box flap crossing midline (ipsilateral half lateral to SSS) | Midline lesions: distal ACA aneurysm, falcine meningioma, corpus callosum, lateral/third ventricle lesions |
Transnasal Transphenoidal | Supine, body flexed, nose in sniffing position | Sphenoid sinus wall removed, may advance to tuberculum sellae/planum sphenoidale | Sellar lesions with/without suprasellar extension or clival lesions |
Petrosal (retrolabyrinthine-middle fossa) | Supine, bolster under shoulder, 60° head turn contralaterally | C-shaped temporal-occipital craniotomy, mastoidectomy, supra/infratentorial exposure, tentorium section | Upper 2/3 clivus and anterior brainstem/basilar artery |
Midline suboccipital | Prone w/ head flexed, chin tuck or sitting (obese/large breasted patients) | Craniotomy below transverse sinus to lip of foramen magnum. C1 laminectomy may be required for 4th ventricle | Cerebellar hemispheres, midline dorsal medulla/pons, pineal region |
Retrosigmoid suboccipital | Supine, bolster under shoulder, 90° head turn to floor, vertex tilt as required | Exposes junction of transverse/sigmoid sinus; bone over sigmoid can be drilled; avoid cerebellar retraction | CPA tumors, cranial nerves V-XI, anterolateral pons, AICA aneurysm, middle 1/3 clivus |
Far lateral suboccipital | ¾ prone, park bench (lateral decubitus), head tucked forward, 120° rotated, vertex tilt | Suboccipital craniotomy from midline to sigmoid; can drill occipital condyle, hypoglossal canal; C1 laminectomy | Lateral and anterolateral foramen magnum, lower 1/3 clivus, PICA aneurysm |
Made with Bullet