Data Lacking in Balloon Catheter Device use for Rhinology
|Pete Batra, MD, discusses the advantages and disadvantages of balloon catheter technology.
Balloon catheter technology (BCT) was first described in rhinology in 1993, but the Food and Drug Administration did not approve the first BCT device until 2005. Six years later, the jury is still out on whether BCT is more effective than other treatments.
"The technology is less invasive, and the profile for complication is very favorable," said Pete Batra, MD, associate professor and co-director of the comprehensive skull base program at the University of Texas Southwestern Medical Center, Dallas. "And outcomes are all over the map."
Potential applications include the maxillary, sphenoid, and front sinuses, Dr. Batra said during the Tuesday miniseminar, "Balloon Catheter Technology in Rhinology: Reviewing the Evidence." BCT procedures can be done in the office and may eventually be used for drug delivery.
BCT also has significant limitations. It cannot be used for ethmoid disease because of access problems. It cannot address osteitis and does not allow for the removal tissue for pathology. And the evidence supporting its use is weak. A recent Cochrane Reviews
analysis concluded that there is no convincing evidence for BCT compared to conventional surgical modalities.
"Cochrane really pushes for level 1 evidence in its evaluations," Dr. Batra said. "But its conclusion raises a significant question. There is a real data gap."
Matthew Ryan, MD, assistant professor of otolaryngology–head and neck surgery at the University of Texas Southwestern Medical Center, also called for better data. Despite multiple studies of BCT, there have been no direct comparisons with traditional modalities and no randomized trials.
"We have become very used to arguing about things in otolaryngology with lower levels of evidence," he said. "We'd have a lot less to argue about if we had better evidence. If we really want information about efficacy, we need comparative studies, and not just one study. We need multiple randomized trials."
Trials supporting BCT have significant shortcomings, he said. The CLEAR Study, often cited for high success rates, offers almost no patient detail. Treatment choices were left to the individual investigator, and there is no data on postoperative management.
Another common problem is inappropriate outcome measures. Most trials use mean Sino-Nasal Outcome Test (SNOT 20) scores. But SNOT 20 is a two-week assessment, Dr. Ryan said, and it has little value in assessing long-term outcomes.
"There is a lot of very careful wording in the conclusions of these studies," he said. "If we don't have a great idea of what these patients were like before and after treatment, it can be tough to externalize the results to our own patients. And the comparative benefit of BCT has yet to be demonstrated."
There are fewer questions about safety and complications. Available data suggest that BCT is safe but subject to some complications, but has not produced any major adverse events, said Raj Sindwani, MD, head of rhinology and sinus surgery at the Cleveland Clinic Foundation, Cleveland, OH.
A 2008 multicenter registry report of 1,036 patients showed just eight complications, all associated with BCT plus concomitant ethmoidectomy. There were six minor bleeds that required cautery or packing, and there were two CSF leaks.
The MAUDE (Manufacturer And User Facility Device Experience) database, maintained by the FDA, shows just 20 incidents as of July 2011. Eight device malfunctions and 12 patient injuries were reported. Injuries included two significant bleeds, for orbital penetrations, five skull-base injuries with CSF leak, and one subcutaneous emphysema, suggesting that BCT may cause similar complications to traditional endoscopic sinus surgery.
Payment for BCT remains problematic. New CPT codes for balloon dilation of the sinuses have been introduced, but
payers want better evidence, said Bradley Marple, MD, professor and vice chair of otolaryngology–head and neck surgery at the University of Texas Southwestern Medical Center.
"We are starting to see an uptake in office balloon use," he said. "But you are not guaranteed payment. We are limited on the payer side by the lack of credible data. The best we can advise you is to talk with the carrier in advance and get its coverage commitment in writing before you proceed."