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Frequently Asked Questions About EEA

UPMC has been a leader in skull base surgery for more than 20 years. Since 1997, the surgical team has performed more than 3,500 Endoscopic Endonasal Approach (EEA) skull base surgeries in adults and children for a variety of benign and malignant (cancerous) conditions. The same team is experienced in traditional skull base surgery and open neurovascular procedures. In collaboration with colleagues at UPMC Children's Hospital of Pittsburgh, our surgeons have performed endonasal surgery on more than 100 pediatric patients.

UPMC is recognized nationally and internationally as one of the leading centers for skull base surgery, and receives consultations and patient referrals from around the world. Surgeons from institutions throughout the world come to Pittsburgh to learn about the latest minimally invasive brain surgery techniques.

The skull base (or cranial base) is the part of the skull (cranium) that supports the brain and separates the brain from the rest of the head. Blood vessels to the brain and nerves from the brain (cranial nerves) run through holes in the skull base. Below the skull base are the nasal passages, sinus cavities, facial bones, and muscles associated with chewing.

Traditionally, neurosurgeons treated conditions that arose within the skull, and otolaryngologists (ear, nose, and throat doctors or head and neck surgeons) treated conditions that arose in the head outside the skull. In other words, the skull base divided these two worlds, and tumors and other diseases that affected the skull base or deep facial tissues were difficult to reach. With the collaboration between surgical specialties — otolaryngologists-head and neck surgeons and neurosurgeons working together as skull base surgeons — these deep areas can now be safely approached.

Over the last decade, new surgical techniques have been pioneered at UPMC that allow the majority of skull base surgeries to be performed through the nasal passages using an endoscope: the Endoscopic Endonasal Approach (EEA).

An endoscope is a lighted instrument that provides visualization within a cavity. All three stages of surgery (approach, resection or tumor removal, and reconstruction) are performed through the nasal passages without the need for scalp or facial incisions. While these types of surgeries are described as minimally invasive, they often allow the surgeons to perform more complete surgeries.

The concept of modern skull base surgery comes from doing a less invasive procedure that can result in a more effective outcome for the patient. While EEA can be the solution for most tumors at the skull base, it is not the answer for all of them. The modern skull base surgeon needs to be versatile in order to offer the best approach for each situation.

Our surgeons are experienced in all types of skull base surgery and utilize a variety of surgical approaches and techniques to design the best operation for each patient.

The Endoscopic Endonasal Approach is a minimally invasive surgical approach to the skull base that was refined and is performed at UPMC by a multidisciplinary surgical team to remove skull base brain tumors and lesions through the nose. EEA is performed using a narrow telescope called an endoscope. A small area at the base of the skull is removed to allow direct access to the tumor, without manipulating the brain. The concept of "inside out surgery" — starting directly at the tumor and working outward — eliminates the need to move critical structures to reach the tumor.

There are many ways to approach the skull base. In the past, the favored technique was to approach the skull base from above (transcranial approach) and from below (transfacial approach), commonly at the same time.

The transcranial approach consists of a scalp incision followed by a craniotomy (removing part of the skull). The brain is then lifted up to reach the skull base. The bones of the facial skeleton may be removed temporarily to increase the exposure.

The transfacial approach consists of incisions on the face or inside the mouth that provide access to the sinus cavities and skull base from below. Working both above and below the skull base, the surgeons then remove tumors. Surgery results in a defect of the skull base and dura (thick lining over the brain) that needs to be repaired to prevent leakage of spinal fluid and infection (meningitis).

For the majority of skull base pathologies, the Endoscopic Endonasal Approach (EEA) is generally enough for treatment. However, there are situations in which a traditional approach is still required. We often combine endonasal and open approaches for specific lesions. This is the concept of 360° surgery around the skull base.

We prefer not to force one angle of surgical approach. If a specific tumor can be totally removed using a single approach, such as endonasal surgery, then we will use that approach. However, if part of the tumor is located on the other side of important structures, such as blood vessels and nerves, we prefer to remove the residual portion using a different corridor, which can be a focused traditional approach. There are also situations in which only a focused traditional approach is necessary.

Our surgeons are experienced in all types of skull base surgery and utilize a variety of surgical approaches and techniques to design the best operation for each patient.

If surgery is recommended, additional testing is often necessary. This may include visits with additional specialists, medical clearance from your primary physician or anesthesiologist, and medical tests. CT and MRI scans are often obtained before surgery for use with an image guidance system akin to a GPS of the brain and skull base.

Some surgeries are scheduled in two stages on separate days. The tumor exposure is performed in the first stage and then removed during the second stage several days later.

Surgery times vary depending of the complexity of each case. For routine cases, surgery often takes two hours from the time anesthesia is administered. More complex cases may take from four to six hours.

From speaking with patients post-operatively, it appears to be much less painful and much less uncomfortable than comparable traditional approaches. Most patients don't need strong medication to control pain, and are discharged on mild pain relievers, such as acetaminophen. The most common complaint is the post-operative nasal packings, which are not used all the time and are removed within one week.

After you leave the recovery room you are transported to one of our step-down units. Rarely, there are specific situations that will require you to go to an intensive care unit (ICU). These situations are related to the patient's age, other diseases they have, and complexity of the surgery.

Once you are awake and oriented in the step-down unit, your family will be notified and they can join you at your bedside. Usually that happens within several hours after the end of the surgery.

Most of our patients are discharged after spending two nights in the hospital. Of course there are situations when patients may need to be observed a little longer, as well as many times when patients can leave the day after surgery.

For a routine surgery, the nasal passage is filled with compressible packing or a balloon catheter. This remains in place for up to one week, depending on the extent of the surgery. This is easily removed prior to discharge or in the office if already discharged. Plastic splints are also placed in the nasal passage, and these are removed several weeks after surgery. Once nasal packing is removed, patients are instructed to spray the nasal cavity with saline (salt water) several times a day.

Patients are seen every few weeks initially for endoscopic examination of the nasal cavity and removal of nasal crusts. By three to four months, healing is usually complete and crusting diminishes. Additional follow up depends on the diagnosis, need for additional therapy, and symptoms.

Patients are instructed to avoid activities that increase pressure of spinal fluid inside the head (bending, lifting, straining, nose-blowing) for a month after surgery in order to minimize the risk of a spinal fluid leak. A spinal fluid leak is characterized by the drainage of clear fluid from the nose. If a spinal fluid leak is confirmed, this can be repaired using endoscopic surgical techniques in most cases.

Most patients will notice a decrease in smell and taste for several months following surgery due to decreased air flow through the nose. This will often recover as healing occurs.

If you have a pituitary tumor or another tumor in which there is no plan to open the lining of the brain (dura), then your chance of having a postoperative leak and requiring follow-up surgery is very low (less than 2%). On the other hand, if you have a tumor that requires the surgeons to open the lining of the brain through the nose, as for meningiomas and craniopharyngiomas, the risk is a little higher. With the development of the nasoseptal flap (vascularized tissue from the patient's own nose that is transplanted from the septum to the skull base), the chance of having a spinal fluid leak after surgery is just 5.4%. (1)

In general, our patients are up and about the day after surgery. However, any time after brain surgery, it is important to rest in order to have good wound healing. The time to go back to work varies, depending on whether the lining of the brain was opened. If it was not, as with pituitary surgery, then the patient often can return to work within days. If it was opened, we generally recommend avoiding heavy lifting for a few weeks to allow for the reconstruction to seal. These questions can be discussed with our team upon follow-up and a decision will be made at that time.

Endoscopic Endonasal Approach (EEA)
Pituitary Tumor Removal Using the Endoscopic Endonasal Approach (EEA) at UPMC

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(1) Endoscopic reconstruction of the cranial base using a pedicled nasoseptal flap. Kassam AB, Thomas A, Carrau RL, Snyderman CH, Vescan A, Prevedello D, Mintz A, Gardner. Neurosurgery 63:ONS44-52; discussion ONS52-43, 2008.