Cerebellar Infarction

The symptoms of a cerebellar infarct clearly depict the region of the cerebellum that is subjected to ischemic damage. In addition to specific symptoms, there are other non-specific symptoms like headaches, dizziness, and vomiting.

A blockage of blood flow in the superior, anterior inferior or posterior inferior cerebellar arteries can result in a cerebellar infarction. The primary region affected is the brainstem, and, therefore, the symptoms clearly depict various degrees of damage to this anatomical structure. Symptoms typical of a cerebellar infarct include dysarthria, diplopia, muscle weakness, limb ataxia and isolated vertigo, usually constituting an occlusion of the posterior inferior cerebellar artery [1].

The symptomatology related to a cerebellar infarction tends to arise spontaneously and then progresses rapidly, while risk factors such as hypertension and cardiovascular disease usually complete the patient's background [2]. Profound ataxia, vertigo, and multidirectional nystagmus are three symptoms that raise considerable suspicion of a cerebellar infarction and should be investigated in depth since their misinterpretation lays the foundation for many cases of undiagnosed cerebellar infarctions [3].

Additionally, multidirectional nystagmus also referred to as gaze-evoked or direction-changing nystagmus, encompasses a change in the direction of nystagmus, depending on the direction of the patient's gaze. This symptom evinces a more than 50% sensitivity for the diagnosis of a cerebellar infarction [4]. In order to elicit an irrefutable gaze-evoked nystagmus sign, extreme lateral strain should be avoided [5]

The workup involved in the investigation of a potential cerebellar infarction encompasses three vital steps: a thorough clinical examination, imaging modalities to confirm clinical suspicion and glucose testing, as well as, investigations to determine the possible cause, should it be unknown.

Initially, a cerebellar infarction caused by a thrombotic event is suspected when an acute neurologic impairment is observed corresponding to the arterial occlusion of a specific cerebellar artery. Non-specific symptoms, such as headaches, vomiting and coma/stupor are more indicative of a hemorrhagic event. A clinical diagnosis of the exact arterial branch that has been occlusion is often impossible, with the symptoms and progression being only indicative of the particular characteristics of each event.

Neuroimaging is an essential method to diagnose the infarction. A computerized tomography scan (CT scan) can detect the region of the arterial occlusion, but its sensitivity increases with the progression of the event [6]. It also constitutes a means to differentiate between a cerebellar infarction, a tumor, hemorrhage, subdural or epidural hematoma and is indicated in patients who require special equipment for monitoring and life support [7]. A magnetic resonance imaging scan (MRI) is able to detect an infarction earlier during the course and with greater sensitivity than a CT scan; small infarctions may even be detected solely by means of a magnetic resonance imaging scan (MRI scan). Diffusion-weighted imaging (DWI) is an extremely useful tool for the evaluation of patients with a transient ischemic attack [8].

In order to diagnose the etiology of the infarction, vascular, cardiac and hematological evaluation are carried out:

Possible cardiac pathology can be detected with an electrocardiogram, telemetry, serum troponin, Holter monitoring and an echocardiogram.

Investigations including a magnetic resonance angiography (MRA), a computerized tomography angiography, conventional angiography, carotid and transcranial duplex ultrasonography, can be performed in order to assess an underlying vascular pathology.

Disorders that affect the coagulation cascade can lead to a hypercoagulative disorder, that may lead to a thrombotic cerebellar infarction. Laboratory evaluation of the platelet count, a complete blood count and a PT/PTT measurement can provide the initial clues of a coagulation pathology. An accurate diagnosis will be established as soon as additional tests are performed, such as homocysteine, antithrombin III, factor V Leiden levels, as well as various other indicators.

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