What causes cerebral vasospasm?
Mood swings, anger and excitement, psychological disorders, tension and stress are the most common causes of cerebral vasospasm. Most of the patients are students, especially high school senior high school students, who are most prone to cerebral vasospasm due to their intense study life, lack of sleep time and complete lack of relaxation, and insomnia can also cause cerebral vasospasm. Young women, brain workers have a relatively high incidence.
How should cerebral vasospasm be diagnosed?
Common diagnostic methods for cerebral vasospasm include CT, digital subtraction angiography (DSA) and transcranial Doppler flow analysis (TCD).
The accuracy of CT diagnosis in finding SAH is over 99%, but the detection rate for aneurysm and cerebrovascular malformation is only 34%, so it cannot be used as the only means of etiological diagnosis.
In clinical practice, the severity of cerebral vasospasm can be estimated based on the amount of bleeding shown by CT, i.e. Fischer grading. According to this criterion, grade 0 is no hemorrhage and the incidence of cerebral vasospasm is about 3%, grade 1 is hemorrhage in the basal pool only and the incidence of vasospasm is 14%, grade 2 is hemorrhage in the peripheral brain pool or lateral fissure pool and the incidence of vasospasm is 38%, grade 3 is extensive SAH with intracerebral parenchymal hematoma, and grade 4 is thicker accumulation of blood in the basal and peripheral brain pools and lateral fissure pool, and the corresponding incidence of vasospasm is more than 50%.
The positive detection rate of whole brain angiography for aneurysm and cerebrovascular malformation is high, which can clearly show the branches of cerebral vessels at all levels, the location and size of aneurysm or the morphological distribution of malformed vessels, and provide a reliable objective basis for treatment, so it has been used as the gold standard for judging cerebral vasospasm. However, it also has certain disadvantages, such as, it is an invasive test, and it is relatively expensive and complicated to operate, which is sometimes not accepted by patients.
TCD is also a good method to monitor cerebral vasospasm after SAH, especially it can be monitored several times in a day, and the dynamic observation of cerebral hemodynamic changes after SAH is of great value to the diagnosis and prognosis of cerebral vasospasm. The basic principle is to estimate the degree of luminal stenosis by the change of blood flow velocity, and the most important test site is usually the bilateral MCA, which can also monitor the blood flow condition of the extracranial segment of the internal carotid artery.
The normal MCA flow velocity is 30-80 cm/s, and the general diagnostic criterion for cerebral vasospasm is a flow velocity of more than 120 cm/s. The advantages of TCD are that it is easy to perform, inexpensive, and non-invasive to the patient, but the indirect diagnosis of cerebral vasospasm by flow velocity has a high specificity but relatively low sensitivity, so it has been proposed that the criterion for TCD diagnosis of vasospasm be lowered from 120 cm/s to 80 cm/s. If vasospasm is suspected, TCD should be performed continuously and dynamically throughout the treatment period.
For microvascular spasm, a new detection method has emerged, namely orthogonal polarization spectroscopy imaging. This method allows qualitative and quantitative analysis of the microcirculation in the cerebral cortex, and the literature reports a significant decrease in capillary density and vasospasm in small cortical arteries and microarteries in the early stages of SAH.
Segmental microvascular spasm occurs in 55% of patients in early SAH, and the reduction in vessel diameter can be as high as 75%, which can cause clinical symptoms and ultimately affect clinical outcome. Based on these findings, the authors of this study concluded that treatment should be initiated early in SAH, even if vasospasm is not yet detected by cerebral angiography or TCD.
What symptoms are easily confused with cerebral vasospasm?
It needs to be differentiated from the following diseases.
1. focal epilepsy Various types of focal seizures have similarity in performance with TIA, such as epileptic sensory seizures or motor seizures that are easily confused with TIA. Tensionless seizures are similar to sudden collapse seizures. The diagnosis of epilepsy can be confirmed by 24-hour EEG Holter monitoring if there is focal epileptic discharges, or considered as TIA if there is no abnormality, or epilepsy if there is focal non-infarct lesion in the brain by CT or MRI.
2, Meniere’s disease vertigo seizures last longer (up to 2-3 days), accompanied by tinnitus, hearing loss after multiple seizures, and no other neurological localization signs.
3. Syncope is usually preceded by black eyes, dizziness and unsteadiness, accompanied by pallor, cold sweat, thin pulse and decreased blood pressure, and transient impairment of consciousness but recovery soon after falling to the ground, without neurological localization signs. It mostly occurs in the upright position.
4. Migraine mostly starts in adolescence, often with a family history, and attacks are dominated by vegetative symptoms such as migraine and vomiting, and less often by focal neurological loss and longer attacks. Whatever the cause, TIA should be considered an important risk factor for the development of complete stroke, especially if it occurs repeatedly within a short period of time. The disease may resolve spontaneously, and treatment focuses on prevention of recurrence.
The common diagnostic methods for cerebral vasospasm include CT, digital subtraction angiography (DSA) and transcranial Doppler flow analysis (TCD).
The accuracy of CT diagnosis in finding SAH is more than 99%, but the detection rate for aneurysm and cerebrovascular malformation is only 34%, so it cannot be used as the only means of etiological diagnosis.
In clinical practice, the severity of cerebral vasospasm can be estimated based on the amount of bleeding shown by CT, i.e. Fischer grading. According to this criterion, grade 0 is no hemorrhage and the incidence of cerebral vasospasm is about 3%, grade 1 is hemorrhage in the basal pool only and the incidence of vasospasm is 14%, grade 2 is hemorrhage in the peripheral brain pool or lateral fissure pool and the incidence of vasospasm is 38%, grade 3 is extensive SAH with intracerebral parenchymal hematoma, and grade 4 is thicker accumulation of blood in the basal and peripheral brain pools and the lateral fissure pool, and the corresponding incidence of vasospasm is more than 50%.
The positive detection rate of whole brain angiography for aneurysm and cerebrovascular malformation is high, which can clearly show the branches of cerebral vessels at all levels, the location and size of aneurysm or the morphological distribution of malformed vessels, and provide a reliable objective basis for treatment, so it has been used as the gold standard for judging cerebral vasospasm. However, it also has certain disadvantages, such as, it is an invasive test, and it is relatively expensive and complicated to operate, which is sometimes not accepted by patients.
TCD is also a good method to monitor cerebral vasospasm after SAH, especially it can be monitored several times in a day, and the dynamic observation of cerebral hemodynamic changes after SAH is of great value to the diagnosis and prognosis of cerebral vasospasm. The basic principle is to estimate the degree of luminal stenosis by the change of blood flow velocity, and the most important test site is usually the bilateral MCA, which can also monitor the blood flow condition of the extracranial segment of the internal carotid artery.
The normal MCA flow velocity is 30-80 cm/s, and the general diagnostic criterion for cerebral vasospasm is a flow velocity of more than 120 cm/s. The advantages of TCD are that it is easy to perform, inexpensive, and non-invasive to the patient, but the indirect diagnosis of cerebral vasospasm by flow velocity has a high specificity but relatively low sensitivity, so it has been proposed that the criterion for TCD diagnosis of vasospasm be lowered from 120 cm/s to 80 cm/s. If vasospasm is suspected, TCD should be performed continuously and dynamically throughout the treatment period.
For microvascular spasm, a new detection method has emerged, namely orthogonal polarization spectroscopy imaging. This method allows qualitative and quantitative analysis of the microcirculation in the cerebral cortex, and the literature reports a significant decrease in capillary density and vasospasm in small cortical arteries and microarteries in the early stages of SAH.
Segmental microvascular spasm occurs in 55% of patients in early SAH, and the reduction in vessel diameter can be as high as 75%, which can cause clinical symptoms and ultimately affect clinical outcome. Based on these findings, the authors of this study concluded that treatment should be initiated early in SAH, even if vasospasm is not yet detected by cerebral angiography or TCD.
How should cerebral vasospasm be prevented?
Cerebral vasospasm is like muscle spasm in tension headache, because cerebral blood vessels are also composed of smooth muscles, and all relaxation measures can treat or relieve cerebral vasospasm. Wax therapy, foot therapy, comprehensive treatment plus medication treatment, can make most patients recover. The following matters should be noted in daily life.
1.Rational diet. It is recommended to eat more fresh vegetables and fruits and less greasy food. Recommended to drink red wine (50-100mml) and green tea, eat yellow food (such as carrots, sweet potatoes, corn, tomatoes, etc.) black fungus and oatmeal.
2, moderate exercise. The best exercise is walking, mastering the “three five seven” exercise is very safe. “Three” refers to a daily walk of 3 kilometers, more than 30 minutes; “five” refers to more than five times a week exercise; “seven” refers to exercise after the heart rate plus age of about 170. this amount of exercise is This is a moderate intensity. In addition, you can also jog, Yuja, taijiquan, cycling, swimming, etc., according to personal circumstances. In the exercise equivalent to walking or jogging 3 km people, can prevent cerebral vascular spasm.
3, quit smoking and limit alcohol. The harm of smoking is indisputable, should be determined to quit. If you can’t quit smoking, it is recommended that you limit your daily smoking to 5 cigarettes or less. Alcohol can be consumed in moderation, it is recommended to drink a small amount of red wine, beer should not exceed 300ml, white wine should not exceed 25ml, do not abuse alcohol.
4. Mental balance. A healthy lifestyle is important, of all the health care measures, psychological balance is the most critical. Eliminate concerns about the disease, establish a correct attitude towards the disease, maintain a calm mind and a happy state of mind, and avoid emotional excitement, which can antagonize almost all internal and external unfavorable factors.