Before explaining what this is about Tarlov’s cyst, let’s start by saying what a cyst is. A cyst is a “bag” filled with a liquid that does not communicate with the outside. The cyst by definition is closed by the membrane that covers it, its structure is like that of a water globe (so that we understand each other). Tarlov cysts are cysts that form around a nerve structure. Usually we find them in the sacral nerve roots.
These cysts are known to exist since Mr. Tarlov found them dissecting human beings already deceased in 1938. To this day we have imaging tests such as magnetic resonance imaging that allows us to see and suspect them as a cause of pain or injury Root. The reality is that in most cases they are random findings in an imaging test and have no meaning. In these cases all the doctors agree to carry out surveillance without need of any type of treatment. Keep in mind that the cyst potentially can grow over time. And what about cysts that are giving symptoms? Then we will see.
We have commented that a cyst in a closed structure. Well, this makes it able to compress structures that have around as are the nerve roots. In some cases it can even erode the sacrum. Compressing sacral nerve roots can be a cause of sciatica. In the medical literature there are not many published cases, perhaps because of the difficulty sometimes to demonstrate the causal relationship between the cyst and the patient’s symptoms. Many times until they are not operated with relief of the symptomatology the causal relation is not confirmed.
These cysts occur mainly in the sacral roots but you must know that they can appear in any nerve root of the spine.
What are the symptoms of Tarlov’s cyst?
Normally, it does not produce any. The most frequent thing is to see it in a patient who has been done an MRI for a low back pain that does not yield and are appreciated, among other lesions, these cysts. But it is not always so and by its characteristics can compress the nerve roots around. The cysts are in the area of the sensitive ganglion so the symptoms are usually of pain and alterations of the sensitivity.
Usually the sacral roots are affected so it can produce symptoms similar to sciatica with low back pain or gluteus pain that goes down the back of the thigh. They may also produce pain in the sacs and alterations in sensitivity or tingling in the perineal region (coccyx, rectum, vagina, and penis). There may be functional alterations such as urinary incontinence or impotence.
Publications appear to reveal that cysts that produce symptoms are more common in women than in men.
Why do Tarlov’s cysts occur?
There are theories for all tastes without a clear explanation. There are theories that attribute it to trauma or obstruction of the cerebrospinal fluid circulation. Others argue that it is due to developmental lesions although there are no cases of Tarlov cysts described in children to support it. Another theory argues that increased pressure in the cerebrospinal fluid could cause the formation of these cysts. This increase in pressure is caused when efforts are made to retain the breath, such as lifting weights ( Valsalva maneuver ).
What treatment does a Tarlov cyst require?
Insisting a little on the same line, most do not need treatment. Only if they are producing significant symptoms can one consider treating them. When we are sure that the cyst is the cause of a problem that is worth trying, there are different treatments that have been done in the past:
– Percutaneous treatments (aspiration of the cyst with a needle, without surgery) have not been very successful, presenting many problems and relapses.
– The surgery seems to give better results. There are supporters of removing the cyst knowing that there is more risk of damaging the nerve. Others prefer to leave the cyst and simply alter it and leave it “open” so that it does not reproduce. A third option is to not simply act on the cyst and operate the space around the cyst by removing bone to leave enough space so that it does not compress the nerve.
In summary, Tarlov cysts in most cases are random findings in imaging tests. They are not given much importance because they are very rarely responsible for significant lumbar and sacral symptoms. In the past, the results of the interventions on these cysts have caused many problems and this makes it very clear that the origin of the problem lies in Tarlov’s cyst. Perhaps this is why they are diagnosed less often. In any case, it is a known cause of injury of sacral nerve roots and lumbosacral pain and the doctors must take it into account.