Embolized Middle Meningeal Artery as a Surgical Landmark in Infratemporal Fossa

SURGICAL TECHNIQUE AND RESULTS

Surgical removal of the giant cell tumor was conducted using an infratemporal fossa approach type B. The day before surgery, embolization of the left MMA was performed. Briefly, right common femoral artery access was obtained using a 5-French micropuncture kit, and common carotid and external carotid angiography were performed using a standard 4-French diagnostic catheter. After super-selecting the left accessory MMA with a microcatheter (Excelsior SL-10; pre-shaped 45″; Stryker Corp., Kalamazoo, MI, USA) and a microwire (Synchro-14; Stryker Corp.), embolization was performed using a detachable coil. A temporal bone CT scan confirmed that the MMA was successfully occluded.

Figure 2. Exposure of the infratemporal fossa. The middle meningeal artery (arrow heads) is lying below, entering the skull base through the foramen spinosum (arrow). The mandibular condyle is retracted.

A large C-shaped postauricular incision was designed, and the flap was elevated superficially to the temporalis muscle. The external auditory canal was closed by meatal skin, and a subtotal petrosectomy was done. The temporalis muscle was reflected, the zygomatic arch was removed and preserved, and then the mandibular condyle was retracted downward to expose the infratemporal fossa. Following substantial removal of the tumor mass using an ultrasonic aspirator in the infratemporal fossa, an embolized coil in the MMA was identified in the medial border of the tumor.

The internal carotid artery and the Eustachian tube were identified inferior to the embolized MMA. Bleeding remained minimal during the procedures. By using the coil in the MMA as a surgical marker, we accurately identified and confirmed the posterior medial boundary of the tumor, facilitating precise tumor removal (Figure 2). Abdominal fat was used to obliterate the dead space, and the skin was closed.

CONCLUSION

Selective embolization of the MMA prior to removal of a giant cell tumor located in the infratemporal fossa allowed us to successfully complete the surgery with minimal bleeding. The embolized MMA also served as a helpful surgical landmark to accurately identify and confirm the boundary of the tumor. Additionally, embolization of the MMA is expected to be useful in endoscopic skull base surgeries, given its potential to reduce hemorrhage and enhance precision in a narrow field of view. In addition, the role of FDG-PET has not been emphasized before, but it was quite a useful imaging method in the diagnosis and follow-up of the giant cell tumor in this case.