Skip to Main Content

++

Neoplasms of the anterior skull base (ASB) continue to challenge skull base surgeons, despite tremendous advances in multidisciplinary management. These lesions represent a diverse group of tumor types located within a surgically treacherous region. Historically, these tumors were considered unresectable. If surgery was attempted, it generally consisted of a lateral rhinotomy which inevitably resulted in incomplete tumor resection and dismal survival outcomes. The first combined neurosurgical and transfacial resections were reported in the mid-1950s, and the craniofacial resection was popularized by Ketcham and colleagues in 1963. Since this time, advances in diagnostic technology, interventional radiology, endoscopic endonasal surgery, and minimally invasive neurosurgery have facilitated the emergence of the young subspecialty of skull base surgery. Contemporary ASB surgical techniques have significantly expanded the limits of technical resectability while consolidating the gains that have been made in reducing morbidity and mortality.

++

The ASB is located at the interface of the central nervous system and the upper aerodigestive tract. ASB lesions may therefore arise from the bones of the skull base, “from above” (intracranially), or “from below” (the sinonasal cavity and orbits).

++

Anatomy of the skull base is covered is detail in Chapter 1 and will only be briefly addressed in this section. The ASB is separated from the central or middle skull base by a line running through the chiasmatic sulcus, the anterior clinoid processes, along the posterior margin of the lesser sphenoid wings, and the superior rims of the greater sphenoid wings. The ASB borders the posterior wall of the frontal sinus anteriorly, the frontal bones laterally, and the planum sphenoidale, or roof of the sphenoid sinus, posteriorly. The major components of the ASB are the orbital plates of the frontal bone, the fovea ethmoidalis, and the cribriform plate. The cribriform plate, situated more inferiorly than the ethmoid roof, is composed of thin bone that is traversed by olfactory nerve fibers, and is easily invaded by tumors. The dura mater attaches anteriorly at the frontal crest and crista galli to form the falx cerebri. The anterior cranial fossa contains the frontal lobes, the olfactory bulb, and the olfactory tract.

++

It is important to clarify that the ASB is distinct from neighboring structures that are often surgically approached with similar techniques. The sella turcica and pituitary gland are constituents of the middle or central skull base, and the clivus is a component of the posterior skull base, not the ASB. The ASB overlaps partially with the anterolateral skull base, which is the region between the mid-orbit and the petrous internal carotid artery, and includes the lateral orbit, infratemporal fossa, and portions of the frontal, sphenoid and temporal bones. This chapter will focus on lesions of the ASB.

Borges A. Skull base tumours: Part I. Imaging technique, anatomy and anterior skull base tumours. Eur J Radiol. 2008;66(3): 338–347.
Vrionis FD, Kienstra MA, Rivera M et al. Malignant tumors of the anterior skull base. Cancer ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessSurgery Full Site: One-Year Subscription

Connect to the full suite of AccessSurgery content and resources including more than 160 instructional videos, 16,000+ high-quality images, interactive board review, 20+ textbooks, and more.

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessSurgery

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.