Clinic

Today was my first foray into ambulatory neurology or "clinic". The day went by fast, and I re-learned quite a bit about the neurological exam. In testing for hearing loss, I got confused about the bone conduction versus air conduction. For some reason I remembered that bone conduction was more sensitive than air conduction, and thus performed the test backwards. No matter - it just means I have to review much of this material.

On the floors, we encountered another interesting case. This is an elderly gentleman who's had a long history of vasculopathies (diabetes, coronary artery disease including by-pass surgery, hypertension, etc.) and had a left cerebellar infarct about 6 months ago. At that time, they found an occluded left vertebral artery and a stenosed right vertebral artery. The plan was for him to get a stent placed into a vertebral or basilar artery but when he went for re-imaging to assess his vascular status, new acute and semi-acute right cerebellar infarcts were found. Listening to his story, they may have coincided with "falls" or questionable loss of consciousness. I was then tasked with reading up on bilateral cerebellar infarcts and after clinic that day I was able to peruse Medline and gather a few articles. Regardless of the etiology, it was rather clear by a decent sized study that his prognosis was not good - those with bilateral cerebellar infarcts in general tended to do worse, had more unpredictable hospital courses, and likely (but not proven) greater recurrences. Meanwhile, in terms of etiology, I believe it's quite likely that his severe atherosclerosis (manifested by his stenotic vessels and coronary artery disease and hypertension) made him vulnerable to atheroembolic strokes. As to why the cerebellar region, several papers seem to point at the lack of sufficient collateral perfusion when stenosis is present.

You can imagine my surprise, then, when cardiology came up and after an echocardiogram showing improvement in his ejection fraction (35%->45%) but questionable new lesions in a perfusion study was considering re-vascularization procedures! I asked the fellow if they were at all concerned about additional strokes given his severe atherosclerosis, and while she acknowledged that it was a risk, she felt it was not a great risk as the strokes did not appear to be embolic in nature but rather more consistent with hypoperfusion. I disagree with that notion, given that most hypoperfusion infarcts are not territorial, tend to be small (<2cm),>2cm) while his new infarcts from two different incidents were less than 2cm there were still localized to the posterior inferior cerebellar artery (PICA). Given his stenotic/occluded vertebral arteries, I fear he is in grave danger of new cerebellar infarcts. Since he was previously ambulatory around the house and didn't give any indications of cardiac deficiencies, e.g. shortness of breath after light exertion or chest pain indicative of ischemia, I'm not sure if re-vascularization is appropriate for him. If he were my grandfather, I think I would have resisted on the grounds that the risks are too high. Until he becomes truly symptomatic from a cardiac viewpoint, I don't see the need to do such an invasive procedure. His reason for admission was really from an incidental finding on MRI indicating acute cerebellar infarct, but he remains asymptomatic except for his "falling spells". Once we've ruled out syncope as the case of the falls, then I think it makes much more sense to "fall-proof" his home, perhaps physical therapy/walker, rather than continue to meddle with his body. I would hate to see him reduced from an ambulatory, semi-independent person into a comatose or severely disabled from additional cerebellar strokes. But as a student, I can do little but stand by and watch. Should I have been more vocal in my opinion with the fellow? She got her information from the notes left by Dr. Gerber the attending who has vastly more knoweldge and experience than I. Where exactly does the medical student stand as a patient advocate?