Analysis of the etiology of acute bilateral cerebellar infarction, this article explains it thoroughly

*For medical professionals to read and reference Cerebral infarction with dizziness, don't miss this cause! Previous studies have found that the incidence of cerebellar infarction is not high, accounting for about 20% of all strokes [1-2], while the proportion of bilateral cerebellar infarction is even lower, accounting for about 17.
4% of posterior circulation cerebral infarction [3]
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Acute cerebellar hemisphere infarction is more common in unilateral, but with the popularization of magnetic resonance technology, more and more cases of bilateral cerebellar hemisphere infarction have been found
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Let's first look at two cases: the case is a 161-year-old male with a history of diabetes, hypertension, coronary heart disease, and hyperlipidemia.
He had low blood pressure a few days before the onset
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He was admitted to the hospital with the main complaint of "dizziness and unsteady walking for 28 hours", accompanied by visual rotation and palpitation
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Physical examination: bilateral pupils of equal size and circle, sensitive light reflex, V-grade muscle strength of both upper limbs, V-grade of bilateral lower limb muscle strength, normal muscle tension, stable and accurate bilateral finger-nose test, and unstable bilateral heel-knee-shin test Accurate, Romberg's sign was positive, and bilateral Barthel's sign was positive
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Head MRI as shown below: Figure 1a Multiple acute infarcts in bilateral cerebellar hemispheres Figure 1b Left vertebral artery occlusion, severe basilar artery stenosis or occlusion Analysis: Acute cerebellar multiple infarction mainly occurs in the bilateral posterior inferior cerebellar artery (PICA) blood supply area, The main clinical symptoms and signs are dizziness/vertigo, nausea and vomiting, ataxia and other signs, most of which are limited to unilateral limbs and appear on the side with the larger cerebellar infarction, and the prognosis is generally good
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The possible pathogenesis of acute bilateral cerebellar infarction in the PICA area mainly includes: (1) anatomical variation of PICA [4,5]: There are two types of variation: (a) PICA supplying both cerebellar hemispheres originates from the same side When the vertebral artery of the vertebral artery is occluded or the common trunk segment is occluded, it can cause bilateral cerebellar hemisphere infarction; (b) the other is the medial branch of the unilateral dominant PICA supplying the bilateral cerebellum The medial area of ​​the cerebellar hemisphere, the lateral branch supplies blood to the posterior inferior cortical area of ​​the ipsilateral cerebellar hemisphere, and its own blockage or blockage at the origin of its vertebral artery can cause bilateral medial cerebellar infarction
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(2) Bilateral multiple emboli caused by bilateral cerebellar multiple embolism
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(3) Bilateral variant PICA originates from the basilar artery, when the basilar artery is blocked
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(4) Hemodynamic mechanism, resulting in low perfusion of PICA in the most distal peripheral branches [5]
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The multiple ischemic lesions in the single arterial domain are mainly arterial-artery, while the multiple ischemic lesions in the bilateral multi-arterial domain are mainly cardioembolism or aortic atherosclerosis
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Although no further examination was done due to the patient's own wishes, it can still be inferred that the patient has the latter three pathogenic mechanisms, namely: the bilateral posterior inferior cerebellar arteries originate from the basilar arteries, and multiple emboli of the basilar arteries simultaneously block the bilateral posterior cerebellar arteries.
In the inferior artery, the patient had a history of hypertension, and the blood pressure was low a few days before the onset of the disease.
It is not excluded that the hypoperfusion of the posterior inferior cerebellar artery may be caused by external hemodynamic factors
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Case: A 268-year-old male with a history of hypertension, diabetes, and cerebral infarction (after the left middle cerebral artery stent was implanted, the left response was slow and the speech was slightly unclear).
He was admitted to the hospital with the chief complaint of aggravation for 1 hour, and there were no obvious accompanying symptoms
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Physical examination: high-level cortical hypofunction, slurred speech, V-grade muscle strength in both upper extremities, V-grade in both lower extremities, normal muscle tone, accurate bilateral finger-nose test, bilateral calcaneal-knee-shin test was not accurate, Romberg Positive sign, bilateral Pap sign positive
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Figure 2a Multiple acute infarctions in bilateral cerebellar hemispheres Figure 2b Analysis of right vertebral artery slenderness: Bilateral cerebellar hemisphere infarctions are mostly caused by bilateral PICA occlusion, and the pathogenesis is mostly related to atherosclerosis, embolism, proximal However, there are few reports of bilateral cerebellar hemisphere infarction caused by arterial occlusion of ipsilateral origin or co-trunk origin due to anatomical variation of PICA
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We have mentioned earlier that there are two main types of anatomical variants related to PICA.
In this case, the patient with acute bilateral cerebellar hemisphere infarction, the right vertebral artery is slender and does not exclude stenosis, and the left vertebral artery is dominant, which is considered as the first variant type above ( 1) (a) - Bilateral PICA co-stem origin
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Figure 3 (Photo source Professor Zhang Xiongwei PPT) Gaida-Hoernick[6] et al confirmed a case of bilateral symmetric cerebellar hemisphere infarction caused by occlusion of the common trunk segment of the posterior inferior cerebellar artery originating from the common trunk by DSA and CTA for the first time.
Cases are similar
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Han[7] also clearly demonstrated through DSA that the common trunk of bilateral medial branches originates from the occlusion of the common trunk segment of one posterior inferior cerebellar artery, resulting in symmetrical infarction of bilateral cerebellar hemispheres
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Cullen[8] confirmed this type of variation by CTA, and analyzed the possible mechanism of this variation
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Conclusion: The vascular variation of the posterior circulation is relatively large, and the responsible blood vessels of cerebellar infarction are quite different from the traditional vascular innervation, and the pathogenesis is complicated
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Generally speaking, the vascular innervation of the anterior cerebral circulation is the left and right internal carotid artery system, and the vascular supply areas on both sides do not cross the midline, but the vascular innervation of the posterior circulation, from the perspective of anatomy and imaging, has a considerable part There is variation, and in many cases blood vessels from one side supply both sides across the midline
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If there are bilateral infarct lesions at the same time, according to Professor Gao Shan's CISS classification principle [9]: any type of infarct involving one anterior circulation or limited to the posterior circulation (except the type of isolated perforator artery infarction); CE (cerebral embolism) evidence; no aortic arch and large artery AT (atherothrombotic) lesions that correspond to or explain the distribution of acute infarction; the pathogenesis should be considered aortic arch plaque rupture cerebral embolism or cardioembolism
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However, in bilateral cerebellar infarction, because the vascular innervation of the cerebellum may have unilateral dominant vascular innervation on both sides, the pathogenesis is more complicated, and a comprehensive analysis should be carried out in order to intervene and treat according to different etiologies and pathogenesis, and ultimately effectively prevent cerebral infarction.
Infarct recurrence
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[4] Kang DW, Lee SH, Bae HJ, et al.
Acute bilateral cerebellar infarcts in the territory of posterior inferior cerebellar artery［J］．Neurology, 2000, 55:582-584.
[5] Han SW, Cho GC, Baik JS, et al.
Bilateral cerebellar infarction caused by dominant medial posterior inferior cerebellar artery［J］．Neurology, 2006, 66: 1125-1126.
[6] Gaida-Hoernick B, von Smekal U, Kirsch M, et al.
Bilateral cerebellar infarctions caused by a stenosis of congenitally unpaired posterior inferior cerebellar artery［J］．J Neuroimaging, 2001, 11(4): 435-437.
[7] Han SW, Cho GC, Baik JS, et al.
Cerebellar infarction caused by dominant medial posterior inferior cerebellar arteries［J］．Neurology, 2006, 66(7): 1125-1126.
[8] Cullen SP, Ozanne A, Alvarez H, et al.
The bihemispheric posterior inferior cerebellar artery［J］．Neuroradiology, 2005, 47(11):809-812.
[9] Gao S, Wang YJ, Xu AD, et al.

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Relevant parties are requested to check separately when adopting or using it as a basis for decision-making
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