Stroke ipsilateral

The benefit of carotid endarterectomy for prevention of recurrent stroke has been studied previously in major trials.25,26 A recent meta-analysis has been completed that has combined these clinical trials to evaluate 6,092 patients.27 Carotid endarterectomy has been shown to be beneficial for preventing ipsilateral stroke in patients with symptomatic carotid artery stenosis of 70% or greater and is recommended in these patients. In patients with symptomatic stenosis of 50% to 69%, a moderate reduction in risk is seen in clinical trials. In all patients with stenosis of 50% to 69% and a recent stroke, carotid endarterectomy is appropriate. In other patients, surgical risk factors and surgeon skill should be considered prior to surgery. The patient should have, at a minimum, a life expectancy of 5 years, and the surgical risk of stroke and/or death should be less than 6%. Carotid endarterectomy is not beneficial for symptomatic carotid stenosis less than 50% and should not be considered in these patients. 

Headache is not uncommon around the time of stroke onset. It is more often severe in primary intracerebral hemorrhage than ischemic stroke, and more often severe with posterior than anterior circulation strokes. If the headache is localized at all, it tends to be over the site of the lesion. Headache is more common in cortical and posterior circulation than lacunar infarcts (Kumral et al. 1995). Severe unilateral neck, orbital or scalp pain suggests internal carotid artery dissection, particularly if there is an ipsilateral Horner s syndrome. Severe occipital headache can occur with vertebral artery dissection. Headache is also a particular feature of venous infarcts. Unusual headache in the days before stroke would suggest giant cell arteritis or perhaps a mass lesion rather than a stroke. 

Neurological examination is primarily to localize the brain lesion but there may also be clues as to the cause of the stroke a Horner s syndrome ipsilateral to a carotid distribution infarct suggests dissection of the internal carotid artery or sometimes acute atherothrom-botic carotid occlusion. Lower cranial nerve lesions ipsilateral to a hemispheric cerebral infarct can also occur in carotid dissection. 

One to two days after stroke onset, the infarcted area appears as an ill-defined hypodense area as vasogenic edema becomes predominant. Within two or three days, the attenuation values become lower, the ischemic area is better demarcated and there may be evidence of mass effect (Figs. 5.1 and 11.3). Later, there may be ipsilateral ventricular dilatation owing to loss of brain substance. Hemorrhagic transformation usually occurs a few days after stroke onset in large infarcts, but it may develop within hours and result in appearances very similar to primary intracerebral hemorrhage (Fig. 16.1) (Bogousslavsky 1991). 

Table 14.2. A Cox model for the five-year risk of ipsilateral ischemic stroke on medical treatment in patients with recently symptomatic carotid stenosis ...

Fig. 18.2. The absolute risk reduction (ARR) at five years of ipsilateral ischemic stroke (top) and any stroke or death (bottom) with surgery in European Carotid Surgery Tria centers in which the median delay from last symptomatic event to randomization was <50 days (fast centers) compared with centers with a longer delay (slow centers) (Rothwell 2005a). Data are shown separately for patients with moderate (50-69%) and severe (70-99%) carotid stenosis. Cl, confidence interval.

Despite the limitations of fMRI outlined above, fMRI studies have shown similar findings to those of positron emission tomography studies in recovery after stroke (Yozbatiran and Cramer 2006 Rijntjes 2006). Increased ipsilateral primary sensorimotor cortical activity with posterior displacement of the ipsilesional focus of activity, bilateral supplementary motor area activation and premotor cortical activation occurs after stroke with use of the affected hand in comparison with use of the unaffected hand (Weiller et al. 1992 Cramer et al. 1997 Cao et al. 1998 Pineiro et at 2001). Specifically, in patients with capsular or other subcortical stroke, good recovery is related to enhanced recruitment of the lateral premotor cortex of the lesional hemisphere and lateral premotor and, to a lesser extent, primary sensorimotor and parietal cortex of the contralateral hemisphere (Gerloff et al. 2006). 

Frericks H, Kievit J, van Baalen JM et al. (1998). Carotid recurrent stenosis and risk of ipsilateral stroke a systematic review of the literature. Stroke 29 244-250 Gaunt ME, Naylor AR, Sayers RD et al. (1993). Sources of air embolisation during carotid surgery the role of transcranial Doppler ultrasonography. British Journal of Surgery 80 1121... 

Fig. 27.4. Absolute risk reduction (ARR) with surgery in the five-year risk of ipsilateral carotid territory ischemic stroke and any stroke or death within 30 days after trial surgery according to predefined subgroup variables in an analysis of pooled data from the two largest randomized trials of endarterectomy versus medical treatment for recently symptomatic carotid stenosis (Derived form Rothwell et ai. 2004b), Cl, confidence interval.

Women had a lower risk of ipsilateral ischemic stroke on medical treatment and a higher operative risk in comparison with men. For recently symptomatic carotid stenosis, surgery is very clearly beneficial in women with > 70% stenosis, but not in women with 50-69% stenosis (Fig. 27.4). In contrast, surgery reduced the five-year absolute risk of stroke by 8.0% (95% Cl, 3.4-12.5) in men with 50-69% stenosis. This sex difference was statistically significant even when the analysis of the interaction was confined to the 50-69% stenosis group. These same patterns were also shown in both of the large published trials of CEA for asymptomatic carotid stenosis (Rothwell 2004). 

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