Case Studies
Case 4: Episodes of transient neurological dysfunction in an elderly man.
A 72-year-old man presents with intermittent episodes of left sided weakness involving his arm, face and leg. Each episode lasts about 20 to 30 minutes and they happen every day, 2 hours after getting up. He is hypertensive on medication (nifedipine – a Ca2+ channel antagonist) which he takes 3 times a day. He smokes 10 cigarettes a day. In the past he has suffered with ischaemic heart disease and angina and has pains in his calves when he walks about quarter of a mile which goes when he rests.
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Carotid angiogram showing a tight stenosis at the origin of the internal carotid artery, with normal external and common carotid artery.
Your Answer:
Correct answer: The most likely explanation for the pain in his legs is intermittent claudication due to restricted blood flow as a result of atherosclerotic change in the main arteries to the legs. It is very unlikely that a lumbar spine scan would help, although some patients develop lumbar canal stenosis as a result of degenerative change in the lumbar spine. Typically these patients develop exercise induced back pain and sensory symptoms in their legs with pain and weakness.
Your Answer:
Correct answer: In order to develop symptoms involving the whole of the left side of his body the lesion must lie above the level of the brainstem in the right hemisphere. Given the intermittent nature of the symptoms and their sudden onset it is likely to be vascular in nature and given his history of hypertension and smoking in a man of this age the pathology is likely to lie within his carotid artery on the right causing him to have intermittent ischaemia of the right hemisphere in the distribution of the middle cerebral artery.
Your Answer:
Correct answer: Speech is typically localized in the left hemisphere since this is the dominant hemisphere. Even in people who are left handed the majority have speech still localized to the left hemisphere.
Your Answer:
Correct answer: The main things to look for on the examination would be any residual neurology down the left side – in particular whether he has any weakness and numbness as well as looking for abnormalities in the right carotid artery such as a bruit. It would also be important to do a full cardiovascular examination to assess the health of his other arteries as well as his heart.
Your Answer:
Correct answer: The standard investigations for people who have transient ischaemia of this nature is to image the carotid artery on that side either with an ultrasound scan or some form of magnetic resonance imaging. In addition one would probably wish to image his brain to see the extent to which he has ischaemic damage there. One would also look for further risk factors for cardiovascular disease such as fasting serum levels of cholesterol and glucose, as well as investigations of his heart (ECG, echocardiogram, etc) if this has not been done already.
Your Answer:
Correct answer: The explanation for this is that he probably drops his blood pressure as a consequence of taking his anti-hypertension treatment. The drop in blood pressure is such that, combined with the carotid stenosis on that side, he has under perfusion of his right hemisphere giving him the symptoms that he describes. Thus a change in anti hypertensive medication to a slow release, longer acting treatment may alleviate the attacks that he is describing.
Your Answer:
Correct answer: Apart from the possible change in his antihypertensive treatment the management would depend on the degree of stenosis within the carotid artery. If this is less than 50-70% one would typically manage him medically with anti-platelet therapy such as aspirin as well as treatments for any diabetes or hypercholesterolaemia if these are found to be present. If the stenosis is greater than 70% then he would probably be offered a surgical correction of his carotid stenosis with a carotid endarterectomy.