Infarct occipital

FIGURE 4.2 (Continued) A compliant balloon was used to perform angioplasty (c). Postangioplasty angiogram demonstrated complete recanalization of the basilar artery and its major branches (d and e). MRI performed 2 days later demonstrated only small areas of infarction in the cerebellar hemispheres (arrows—f and g) but no brainstem or occipital infarcts. 

Alexia without agraphia in left occipital lobe infarction and the splenium of the corpus callosum. Transfer of read words from the functional right visual cortex to the left sided language center is impossible due to interruption of the splenium. Transfer of primary language information for writing or speech is not impaired. 

Jongen JCF, Franke CL, Ramos LMP et al (2004) Direction of flow in posterior communicating artery on magnetic resonance angiography in patients with occipital lobe infarcts. Stroke 35 104-108... 

Brainstem, cerebellar, thalamic or occipital lobe signs normally indicate infarction in the distribution of the vertebrobasilar circulation or a localized hemorrhage. 

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. 

Diffusion-weighted MRI showing two areas of acute infarction in the left parietal and occipital regions, (b) Magnetic resonance angiography shows aberrant arterial anatomy with the posterior cerebral artery arising directly from the internal carotid artery (arrow) (c) This was confirmed on catheter angiography. 

A 29-year-old man had a subarachnoid hemorrhage due to an arteriovenous malformation, which was embo-hzed (101). During the procedure he suddenly lost consciousness, regained it 15 minutes later, but complained of total blindness. Cerebral angiography showed no arteriovenous malformation and no abnormality in the vertebrobasilar system. A CT scan of the head showed considerable contrast enhancement of the occipital lobes and 2 hours later the contrast had cleared. An MRI scan 12 hours later showed no evidence of infarction in the occipital lobes. Two days later his sight gradually returned and 7 days later he had completely recovered. 

Rapid lowering of the blood pressure with nifedipine, particularly sublingually, can precipitate cerebral ischemia, with confusion, loss of consciousness, and stroke. Cases of cortical blindness with macular sparing secondary to occipital lobe infarction have been reported (SEDA-17, 238). 

Stroke occurred in an 8-year-old boy on chronic peritoneal dialysis after he took phenylpropanolamine (5). He developed occipital infarcts and was found to have extremely high concentrations of phenylpropanolamine in his blood and dialysis fluid. Although the voluntary recall was in effect, the family already had a bottle of phenylpropanolamine at home. 

Fig. 7.19 Posterior reversible encephalopathy syndrome. Sixty-four-year-old female with mental status changes. FLAIR images demonstrate hyperintense lesions in the bilateral parietal occipital regions that suggest acute infarctions arrows). The lesions...

A 64-year-old man with a 2-day history of bleeding from the rectum became unresponsive. He had taken long-term warfarin because of atrial fibrillation and had received an inactivated influenza vaccine 1 month before admission. The INR was raised, after having been stable for at least 6 months. A CT scan showed a large parenchymal hemorrhagic infarct involving the left temporal, parietal, and occipital lobes. He died about 17 hours after admission. 

Perhaps the most significant complication reported is vertebrobasilar accident with rotary cervical manipulation, such as reported by Git-tinger. In some persons, rotation and extension of the cervical spine cause narrowing of the vertebral artery on the side opposite the rotation. Pre-existent compromise of cranial collaterals, such as the carotids, must be considered. Occipital infarction may result, with various neurologic sequelae. Some considerations when using cervi-... 

Gittinger JW. Occipital infarction following chiropractic cervical manipulation. J Qin Neuroophtfudmol 1986 6 11-13. 

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