Case Archives — Clival and Foramen Magnum Meningioma Embolization and Transnasal Resection

Case courtesy of Dr. Chandra Sen, NYULMC.

Combined embolization and transnasal resection.

Patient presents with early signs of brainstem compression.

Clival and Foramen Magnum Meningioma

Clival and Foramen Magnum Meningioma

Notice stretching of the VIth nerves

Clival and Foramen Magnum Meningioma

Tractography confirms presence of craniocaudally oriented white matter tracts in the medulla

Clival and Foramen Magnum Meningioma

The tumor is situated immediately above the odontoid process.  The soft palate is marked with yellow arrow

Clival and Foramen Magnum Meningioma

CTA shows tumor vascularity and an enlarged arterial branch within the left hypoglossal canal.  What branch is it?

Clival and Foramen Magnum Meningioma

Sagittal recon

Clival and Foramen Magnum Meningioma

Angiogram shows proximal basilar fenestration and hypoplastic left PICA.  Clival venous plexus is not seen.

Clival and Foramen Magnum Meningioma

Stereo views

Clival and Foramen Magnum Meningioma

Another standard view of the left vert. Both transverse/sigmoid sinuses are patent. There small inferior petrosal sinuses present.

Clival and Foramen Magnum Meningioma

Stereo views

Clival and Foramen Magnum Meningioma

A small anterior spinal artery is seen arising from the vertebrobasilar junction, in a Y-configuration.  It is a key artery to preserve, for obvious reasons.  White arrows point to the origins, and red to the anterior spinal artery

Clival and Foramen Magnum Meningioma

Right vertebral artery stereo views.  There is a dominant cervical radiculomedullary artery supplying the anterior spinal system arising from the right C5 level.  The right PICA is intradural however the tonsillar loop extends below the foramen magnum slightly.

Clival and Foramen Magnum Meningioma

Native views

Clival and Foramen Magnum Meningioma

Left ICA views show no MHT contribution.  The venous system is patent. There is no clival venous plexus.

Clival and Foramen Magnum Meningioma

Same deal on the right

Clival and Foramen Magnum Meningioma

Right ECA has a small tumor blush from the ascending pharyngeal

Clival and Foramen Magnum Meningioma

Bulk of tumor supply comes from the left neuromeningeal trunk.

Clival and Foramen Magnum Meningioma

Normally the neuromeningeal trunk and pharyngeal trunk are the two main branches of the ascending pharyngeal artery.  In this patient however the pharyngeal trunk (yellow) and the neuromeningeal trunk (red) arise separately from the occipital artery — probably reflecting different embyologic origins of the two trunks.

Clival and Foramen Magnum Meningioma

Stereo views

Clival and Foramen Magnum Meningioma

Right neuromeningeal trunk.  Not much of a blush, but for transnasal resection the goal is complete devascularization, so we embolize with 45-150 micrometer Contour particles

Clival and Foramen Magnum Meningioma

The branch is then closed with detachable coils (Stryker 1 by whatever mm nanocoils, these things are so soft they pack great in these small vessels.  Choose the longest one that works, and it is usually more than enough to close it. A bit expensive, compared to the usual pushable fibercoils we use for this purpose, but in these vessels the microcatheter is too small for the pushables we have.) The tiny coil pack is just under the skull base.

Clival and Foramen Magnum Meningioma

Nothing from the left pharyngeal trunk, as expected

Clival and Foramen Magnum Meningioma

Left neuromeningeal trunk supplies the bulk of tumor, via the hypoglossal division. This is the branch which was seen on the CTA in the hypoglossal canal, and by definition is the only arterial branch that can be in that canal.

Clival and Foramen Magnum Meningioma

Post particle and coil embo

Clival and Foramen Magnum Meningioma

Next comes the odontoid arcade. Same SL-10 microcatheter

Clival and Foramen Magnum Meningioma

Not much of a blush, but it goes to the inferior part of tumor, that might be difficult to see and every bit counts here.

Clival and Foramen Magnum Meningioma

Post particle and coil embo

clival and foramen magnum meningioma embo

Same on the right

clival and foramen magnum meningioma embo

Pre

clival and foramen magnum meningioma embo

Post

clival meningioma embolization

Neurologic status unchanged post embo. All CN fine.

Resection

Courtesy Drs. Chanra Sen of neurosurgery and Seth Lieberman of ENT, NYULMC

Transnasal resection — access by Dr. Lieberman.  At this point tumor almost ready to come out.  These are some of the most amazing views of the living brainstem

Clival Meningioma Resection Transnasal

Tumor with posterior capsule intact is folded downward to reveal the vertebrobasilar junction

Clival Meningioma Resection Transnasal

Working around the left lateral edge

Clival Meningioma Resection Transnasal

Hypoglossal nerve origin in view

Clival Meningioma Resection Transnasal

More hypoglossal nerve is visible now as arachnoid is removed

Clival Meningioma Resection Transnasal

After removal of tumor. Amazing

Clival Meningioma Resection Transnasal

Another view

Clival Meningioma Resection Transnasal

Finally, a video of the final neurosurgical part of the operation. If video link does not work click here to play manually

MRI post resection. Fat packing on both sides of dural defect is present

clival meningioma embolization

clival meningioma embolization

Fat packing is white. Dural reconstruction is red

clival meningioma embolization

Questions/Comments here 

See parent page Brain Tumor Embolization for more Cases