I’m currently in the midst of doing a literature review in preparation to write a case report. If you would like more background information on the case or information about the project, please click here. If you would like to see other article reviews related to this project, please click here.
(My institution library is having a hard time connecting to the article server today for some reason. I’ll keep trying to get a direct link, but in the mean time, enjoy the summary.)
The cerebellum is small compared to the cerebrum’s volume, BUT it regulates over half of the neurons in the brain and plays important roles in cognition (thinking), behavior and motor balance. Since I only directly treat the motor balance part, I won’t be going into the cognition or behavior too much, except where it effected my treatment of the motor balance. Cerebellar strokes are only about 10% of all strokes and only 2-3% of those are ischemic; however, they typically lead to worse outcomes. Cerebellar stroke symptoms are variable, but the more common symptoms include: sudden nausea, vomiting, headache, dizziness, unstable gait and changes in coordination, imbalance, eye movements, swallowing, talking, hearing, or vision. Ischemia (lack of blood flow) in the cerebellum is typically caused by a clot (embolism) or cholesterol deposits in the arteries (large vessel atherosclerosis), but can also be associated with a tear in the lining of the verterobasilar artery (vertebrobasilar dissection), conditions that cause the body to make clots (like atrial fibrillation or taking those estrogen based birth control like mentioned in the last article), or vessel inflammation (vasculitis).
The posterior inferior cerebellar artery (PICA) is usually the culprit. PICA strokes present with “severe isolated vertigo and vomiting, but most commonly have unidirectional spontaneous nystagmus with gait imbalance called truncal lateropulsion, described as the feeling of pulling of the trunk to the [same side as the stroke.]… A stroke involving the lateral PICA territory causes minor dizziness, gait imbalance, limb hypotonia and incoordination, and abnormal rapid alternating motions [….] If the full PICA territory is involved, an occipital or high neck headache will be present on the [same side as the stroke], sometimes with head tilting toward the [same side as the stroke….] When a PICA stroke simultaneously involves the medulla, intractable hiccups can be present.”
The other main arteries can make strokes too, but will look different. “… [An anterior inferior cerebellar artery] AICA stroke presents most often with vertigo that gradually improves, but can also cause permanent unilateral or bilateral hearing loss with associated symptoms including facial palsy, Horner syndrome, or sensory loss…. When the [superior cerebellar artery] SCA is involved it rarely causes vertigo, but lateral SCA involvement can present with dizziness, imbalanced gait, and truncal and limb ataxia. Similarly, medial SCA involvement can cause gait ataxia, described as sudden falling or veering.”
The brainstem can also be involved in cerebellar strokes, which will have other associated signs/symptoms, which are beyond this article’s scope. As always the 3 most important rules in neuro path are: 1. location, 2. location, 3. location.
The differential will include: migraines, vertigo, peripheral vestibular disorders, orthostatic hypotension, dehydration, gastrointestinal complaints, psychological syndromes, cerebellar cognitive affective syndrome and multiple sclerosis.
Since this article is about managing these in the emergency room, they talked about when they do in these cases there to treat them. The treatments fall into controlling blood pressure, busting up the clot or removing it and maybe surgery to relieve pressure on the brain.
The case that I’m working on doesn’t have imaging with it and none of the documentation states the specific location of the stroke. I do recall in discussing the case with the PM&R physician that was managing the case with me that it wasn’t really just 1 spot, it was several small lacunar or deep infarcts. These are typically caused by several tiny clots in very small vessels. But judging by the descriptions above, I would guess the majority of the damage would have been the PICA territory.