Skull Base Tumors

The surgeons at MUSC Health were some of the first in the country to perform endoscopic skull base surgery. These cases represent close collaborations between our neurosurgeons and our rhinologists (sinus surgeons). Endoscopic approaches have demonstrated quicker recovery with fewer complications than traditional “open” approaches through incisions while still achieving similar success rates for the treatment of tumors. These cases are typically started by the rhinologist who opens the sinus cavities widely. The portion of tumor at the skull base is then removed by having our neurosurgeon work through one nostril, while the rhinologist works through the other. This “two surgeon” approach provides the advantage of having two brains and four hands working on each case. Our team has written over 40 articles describing surgical techniques and results using endoscopic, minimally invasive approaches to skull base problems. These cases can be broken up into a variety of types.

What is endoscopic skull base surgery?

Endoscopic skull base surgery is a technique similar to ESS except that the surgery is focused on removing tumors or fixing abnormalities located at the bottom of the brain and/or the brain itself. Like sinus surgery, cameras, video equipment, and other instruments allow the surgeries to be completed entirely through the nose without any facial incisions. Unlike earlier techniques used, this technique may be significantly less painful and result in a shorter hospital stay. While this type of surgery is an attractive option, it must be emphasized that this technique is not for all patients or tumors. Your surgeon will be able to tell you if you are an appropriate candidate.

Cerebrospinal Fluid Leaks & Encephaloceles

When there is a defect in the bone of the skull base and dura, then cerebrospinal fluid (CSF) can leak into the nose. If the lining of the brain or a small portion of the brain herniates into the nose, this is called an encephalocele. These conditions increase the risk of meningitis or other infections of the brain. These leaks can occur spontaneously, after trauma or prior surgery, or in rare cases can be congenital. Endoscopic repair is successful in reducing this risk of meningitis and most leaks can be repaired without any incisions. Our group has published over 25 articles on techniques for treating CSF leaks and is one of the leading centers in the US for these conditions. 

Sagittal CT with a large segment of missing bone and an encephalocele herniating down into the nose.

MRI demonstrating spontaneous encephalocele herniating into sphenoid sinus.

Benign Sinus Tumors

The most common soft tissue tumor in the sinuses is inverted papilloma. Other benign tumors include juvenile nasopharyngeal angiofibroma (JNA), schwannoma, hemangioma, adenoma, or squamous papilloma. Benign bony tumors are often osteomas or ossifying fibromas. These benign tumors can usually be removed endoscopically. Extensive tumors may require an incision along the brow, but this is uncommon.

MRI (top) and CT (bottom) of an inverted papilloma that eroded into the eye and brain was removed endoscopically.

A large osteoma fills the frontal sinus. This was removed endoscopically.

A Juvenile Nasopharyngeal Angiofibroma (JNA) that was removed endoscopically.

Malignant Sinus Tumors   

Malignant sinus tumors are fortunately quite rare. There is a wide spectrum including esthesioneuroblastoma (olfactory neuroblastoma), squamous cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, melanoma, nasopharyngeal carcinoma, and neuroendocrine tumors. Treatment for these tumors usually begins with aggressive surgical resection. This can often be done endoscopically. Postoperative treatment may involve radiation therapy or chemotherapy, depending on the extent of the tumor.

Endoscopic view and MRI after complete resection of esthesioneuroblastoma.

An esthesioneuroblastoma extending into the brain of a patient.

Pituitary Tumors

Most pituitary tumors are benign and are removed when they become large enough to impair vision, cause headaches, or affect nearby structures. The endoscopic approach provides superior visualization and outcomes are equivalent or better than older approaches using microscopic techniques. Other tumors secrete hormones and may need to be removed if medical treatments fail. We work closely with our endocrinologists in the medical management of these pituitary tumors. Other lesions in the region of the pituitary gland include craniopharyngiomas and Rathke’s cysts and these can also be treated endoscopically.

MRI demonstrating large pituitary tumor.

MRI of a craniopharyngioma above pituitary gland.

Other Skull Base Tumors & Lesions

Other skull base tumors that can be removed endoscopically include meningiomas, chordomas, chondrosarcomas and cholesterol granulomas. Open approaches to these challenging areas often require brain retraction or operating through otherwise normal structures. The endoscopic trans-nasal approach permits surgeons to reach these critical areas with minimal disruption of the brain and other vital structures.

A cholesterol granuloma adjacent to the carotid artery was treated endoscopically.

CT and MRIs demonstrating various meningiomas that have been removed endoscopically.