Surgical Treatment of Recurrent Respiratory Papillomas
The primary treatment used for recurrent respiratory papillomas (RRP) is surgical removal. For severe cases of RRP with multiple recurrences, several types of non-surgical methods have also shown some promise in reducing the growth rates of these benign neoplasms. Those methods are described elsewhere; this page concentrates on surgical removal of laryngeal papillomas.
Surgical removal of laryngeal papillomas is most often done with a procedure called microscopic direct laryngoscopy. The is an operation in which the patient is asleep and an instrument called a laryngoscope is placed into the mouth and positioned in such a way that the vocal folds can be directly seen. Since precision is important when operating around the vocal folds, the operation is usually done with either an operating microscope or with special telescopes that give a close-up magnified view of the papillomas and the folds.
There are several different way to actually remove the papillomas, depending on their location, their size, and the surgeon's preference. The goal is to remove as much of the papilloma as possible with minimal damage to the surrounding tissue. The surgery is complicated by the fact that normal appearing tissue may be infected with the virus so simply removing the papilloma does not guarantee that it will not come back.
One of the most common ways to remove papillomas is with the carbon dioxide laser. The light from this laser is in the infrared region of the spectrum and therefore cannot be seen. A second laser that is red in color is therefore used as the "aiming" beam. The advantage of the carbon dioxide laser is that the energy is absorbed right at the surface of the cell, and less energy is transmitted to the deeper normal tissue. The papillomas are either vaporized or burned off in this manner. The laser also tends to coagulate as it cuts so there usually is less bleeding.
One of the drawbacks of the light from the carbon dioxide laser is that it cannot be transmitted through the usual optical fibers. As a result, it must be pointed directly onto the tissue to be treated. In some cases the papillomas are located in spots that can't be treated in this fashion. For these cases, it may be possible to use a laser called the KTP laser. This laser produces light in green portion of the spectrum and it can be passed down a thin optical fiber.
 |
This photo is taken through a tube called a bronchoscope and shows a papilloma along the wall of the trachea (windpipe). This lesion was about 3 cm below the vocal folds and could not be reached with the carbon dioxide laser. A small optical fiber was passed through the bronchoscope and the KTP laser was used to treat the papilloma. In this photo you can see the fiber coming in from below with its end just above the lower portion of the papilloma. |
 |
This photo shows the actual treatment. The green light is very bright and washes out everything in the photo. |
A second technique is to simply carefully grab the papillomas with a small cupped forcep and pull them out. This has the advantage that there is no risk of thermal injury to the adjacent tissue, but can be a bit bloodier than using the laser.
 |
The illustrations to the left show removal of papillomas using this method. This individual had papillomas in the very front of his vocal folds, a region called the anterior commissure. Because of his anatomy, it was very difficult to see this area through the microscope. The operation was therefore done looking through a 70 degree telescope (shown here). This is a telescope that has an end something like a periscope in that when you look through it you don't see straight ahead but rather you look off at an angle of 70 degrees. It allows you to look around corners into areas that otherwise couldn't be seen from above. |
 |
Operating on the anterior commissure is difficult because it can leave a small web-like scar across the very front portion of both vocal folds. One way to minimize this risk is to only operate on one side at a time. This allows the raw surface of the operated side to heal before approaching the other side. |
A new technique for removing papillomas uses a special endoscopic surgical instrument that shaves and suctions the lesions out of the airway. The instrument is a long thin tube that has a small rotating shaving device on it end. The surgery is often done with an endoscope (telescope) instead of a microscopic. The drawing below the left (from a brochure by Xomed, one of the companies that makes this equipment) shows how the shaving device in action. On the right is a close-up of the actual cutting portion of the insturment.
These devices are useful because papilloma removal is usually quicker, less bloody, and there isn't any thermal damage to the adjacent tissue. Moreover, with the telescope it is easier to remove papillomas down in the trachea. However, there are no long-term studies yet to show if shaving reduces the recurrence rate of papillomas or if it causes less damage to the larynx.
 
|
