Salivary gland stones form when the salts within the saliva crystallise. These crystals can gradually become larger over time and cause blockages within the salivary gland ducts if the stone grows to more than approximately 2mm in size. Salivary gland stones are not so common, with approximately 60 people per million affected per year, though if you have them they can become painful and troublesome. Here, consultant maxillofacial surgeon, Miss Katherine George, explains the different ways they can be removed.
There are several different ways of removing salivary gland stones. The treatment of choice depends on the location of the stone within the salivary gland and also the size of the stone. If stones are really tiny, basket retrieval of the stone may be best.
With basket retrieval, an endoscope, which is a thin tube with a camera and light source at one end, can be placed directly into one of the salivary gland ducts. Through this, you can see directly into the duct and see the stone. Once the stone can be seen, you can introduce small wired baskets through the endoscope and into the duct system of the gland, to grasp the stone with the basket and remove it through the endoscope.
Breaking down salivary gland stones
If stones are a little larger, there are several different ways of breaking them into smaller pieces so they can either be flushed through the ducts spontaneously or made small enough to be amenable to basket retrieval.
The site of the stone within the gland is also really important because if they’re near the point of exit into the mouth, you can often feel them and they may be removable with just a small incision. However, if they’re much deeper in the gland, it’s more challenging and often impossible to remove them via incisions. In these cases, the use of an endoscope is essential.
Large salivary gland stones
Much larger stones might be resistant to fragmentation or it may just be impractical to try to keep breaking a really large stone down into small pieces because it might take too much time.
If this is the case, then a surgical approach to remove them is possible, such as making a cut directly where the stone is if you can feel it and removing it directly, putting some dissolving stitches through the duct wall to close it and to aid healing.
Future advancements of salivary gland stone removal
There have been some really exciting advancements in minimally invasive salivary gland surgery. One of which is the advent of a device called Stone Breaker.
This is a device that breaks up and fragments larger stones into smaller pieces so that they can be removed through the duct system. It’s what is called a pneumatic lithotripsy device. It is powered by carbon dioxide and is a really long probe that can be put through the working channel of a small endoscope. Once the stone has been identified through the endoscope, you can pass the long probe with the stone breaker through the working channel and place it directly onto the stone, at which point you can apply a pressure wave through the wire, which hits the stone and breaks it into little tiny pieces.
It can be quite a time-consuming process and each session takes an hour to an hour and a half, but it’s really quite successful. It means that often a surgical approach to remove a stone isn’t necessary.
The benefits of minimally invasive salivary gland stone removal
These techniques have reduced the need to remove salivary glands to approximately just 3% of cases. Salivary gland removal carries certain risks, such as scarring and nerve damage.
The particular nerves at risk if you’re removing an entire salivary gland include a nerve that supplies movement to the side of the face, so you can have paralysis as a consequence of surgery. This can also cause weakness of the tongue and also altered taste sensation or sensation generally to the side of the tongue.
These minimally invasive techniques to remove the salivary gland stone but retain the gland avoid many of the nerve complications of gland removal surgery, which is why they’re so useful.
If you think you may have salivary gland stones, and would like to make an appointment with a specialist, click here.