Our brain is a fundamental part of the body since it regulates the functioning and coordination of most of the body and allows us to be who we are: it controls everything from vital signs to higher processes such as reasoning or motivation, including perception and motor skills, among others.
But although it is perhaps our most important organ, it could not function and would even die in a short time if it did not receive a constant supply of oxygen and nutrients. These reach you through the cerebrovascular system, with the neurons being irrigated by different blood vessels.
Now, sometimes these vessels can suffer injuries or be affected by diseases that can cause blood to flood part of the brain or not reach the places where it should, which can have very relevant repercussions on health. Among these problems we can find Moyamoya disease of which we will see the main characteristics throughout this article.
It is called Moyamoya disease. rare but dangerous cerebrovascular disorder characterized by a progressive occlusion or stenosis of the internal carotid arteries (generally occurring in both at the same time) and their main branches in their terminal parts inside the skull.
This narrowing in turn causes the formation and strengthening of an extensive secondary network of minor vessels that allow blood to continue arriving, forming a circuit. whose shape in neuroimaging is reminiscent of cigarette smoke (This is what the term Moyamoya refers to, which in Japanese refers to smoke).
Although in many cases it can remain silent and asymptomatic, the truth is that since there is progression of the narrowing of the carotid artery, this causes the blood that reaches it to travel at high speed, something to which is added the fact that the network secondary does not have sufficient capacity to carry a sufficient supply of oxygen and nutrients.
This can have important repercussions for the subject, who may experience dizziness and mental slowing, malaise, irritability, vision or speech disturbances, weakness or paralysis on one side of the body, seizures and even can cause the appearance of ischemic strokes or even cerebral hemorrhages if a vessel breaks (something that is more common in this disorder since the secondary network is much more fragile than the carotid), something that can lead to to the loss of physical or mental abilities (depending on the affected area) or even death. The symptoms are usually more noticeable when exertion.
Although it can appear in people of any age, the truth is that it is much more common in children between five and nine years of age, in whom it could cause problems and developmental delays or even intellectual disability. Another peak in cases has also been observed in those adults over 45 years of age. When it comes to sex appears in both men and women although it is more predominant in the latter.
Moyamoya disease was discovered by doctors Takeuchi and Shimizu in 1957, and originally thought to be exclusive to the Japanese population However, over time it has been discovered in people of different ethnicities, although it continues to be much more prevalent in the population of Asian origin).
Regarding the prognosis, it can vary enormously depending on when it is detected and the application of treatment. The mortality associated with this disease is around 5% in adults and 2% in children, mostly derived from stroke.
As we have indicated, Moyamoya disease is a progressive alteration that worsens over time, having established different stages or degrees depending on the stenosis In this sense we find six degrees.
Grade 1
Moyamoya disease is considered grade 1 when it is observed only a narrowing of the point where the internal carotid artery bifurcates
Grade 2
A more advanced degree occurs when the collateral vessels or secondary network that give the disorder its name begin to be generated.
3rd grade
At this point in the disease, the collateral vessels begin to intensify while a progressive narrowing of the internal carotid and middle cerebral artery depending largely on collateral vascularization.
Grade 4
The network of collateral vessels that originates in the internal carotid begins to weaken and have worse functionality, while flow increases and circuits are generated at the level of the external carotid (outside the skull).
Grade 5
The network of collateral vessels develops and intensifies from the external carotid artery, while in the internal carotid artery the collateral network is greatly reduced.
Grade 6
The internal carotid artery is completely closed and its collateral network also ends up disappearing, ceasing the initial secondary circuit The blood supply becomes dependent on the external carotid and the vertebral artery.
Causes
Moyamoya disease does not have a completely defined cause, being an idiopathic disease. Despite this the existence of genetic influence has been observed, having studied chromosomes such as 3, 6 and 17 and having observed that it is more common in the population of Asian descent and in people with relatives who have suffered from it. This aspect is also taken into consideration because it is sometimes associated with genetic disorders.
Furthermore, in some cases it can be associated with infectious processes (in which case it would be a syndrome and not a disease, since it would be secondary to it).
Treatment
Moyamoya disease does not currently have a treatment that cures or reverses it, although the symptoms can be treated and have the level of stenosis or possible damage to blood vessels under control
Among other methods, the surgical method stands out, through which revascularization surgery can be performed, which will improve circulation although the vessels will have a tendency to narrow again (despite the fact that the treatment usually stops the symptoms and their progression). It is also possible to use, although it is done in adults but not in children due to the risk of bleeding after blows, to use very specific anticoagulants and other substances that allow the behavior of the blood to be regulated.
Also Complications that may arise, such as learning delays and intellectual disabilities, should be treated, offering guidelines and educational support when necessary. Speech therapy and/or physiotherapy can be useful in cases with speech or movement impairment, as well as occupational therapy and psychoeducation for the family.
