Endoscopic approach best for repairing bone defect between brain, nasal cavity

The best approach for repairing breaks in the thin bone that separates the brain from the nasal cavity is through the nasal cavity, according to an analysis of 92 patients who had this increasingly common approach to treating a fortunately rare problem.

The intranasal endoscopic approach is the best way to treat a potentially very bad problem,” says Dr. Stilianos E. Kountakis, vice chair of the Medical College of Georgia Department of Otolaryngology-Head and Neck Surgery and principal author of the study published in the October issue of The Laryngoscope. The alternative is opening the skull, moving the front portion of the brain out of the way – destroying smell nerves in the process – and approaching the defect from the top, an approach that may be necessary if the defect is too big to treat endoscopically, Dr. Kountakis says.

However, Dr. Kountakis suggests trying the endoscopic approach – which uses small cameras and monitors so surgeons can operate with minimal trauma – several times before resorting to the open procedure. The condition, called cerebrospinal fluid rhinorrhea, results when trauma or high pressures inside the skull cause a break that allows a direct communication between the nose and brain, potentially causing meningitis and even death.

When the cerebrospinal fluid escapes through the nose, loss of protective fluid around the brain can cause headaches as well as the uncontrollable dripping. “That is something that is classic,” says Dr. Kountakis, who directs the MCG Georgia Sinus and Allergy Center. “People say when they go to church and bow their heads to pray, fluid runs out,” he says, noting that any activity that tilts the head downward or increases internal pressure, from exercise to straining to use the bathroom, can cause dripping. “You cannot stop it,” he says. “Mucous from the nose, you always are able to sniff back. But because this fluid has such a low viscosity, when it runs, it runs uncontrollably.”

As bad as that may sound, Dr. Kountakis says the biggest concern is brain infection, seizures and even death that can result when nasal contents work their way into the brain. “It’s not a major cause of meningitis, but 10 to 50 percent of the people who have a cerebrospinal fluid leak will get meningitis.” A small portion of the brain also can move into the nasal cavity through breaks in the thin bone at the base of skull and between the eyeballs, he says.

The study looked at the results of 92 patients age 6-81 who had endoscopic repair of the condition over a 12-year period at the University of Virginia in Charlottesville where Dr. Kountakis was on faculty before he came to MCG in July 2003. 92 percent of patients had long-term success; the endoscopic approach was successful the first time in 85 percent of patients. Five patients who had large defects eventually needed the open-skull procedure.

Causes of cerebrospinal fluid rhinorrhea include head trauma, sinus surgery, neurosurgery, brain infections, increased intracranial pressure caused by obesity, and cosmetic surgery of the nose. Prior endoscopic sinus surgery was the cause of the leak in 25 percent of patients. “It’s a known risk of the operation,” Dr. Kountakis says, “But if it happens during surgery, it should be repaired then.”

To visualize the defect, doctors use a contrast medium and computerized tomography and may need instruments to probe the area to identify the location of the tiniest leaks. They can use nasal mucosa, cartilage and abdominal fat to repair holes. Patients are hospitalized for several days and shouldn’t exert themselves following surgery.