The isolated occlusion of the angular gyri artery. A correlative neurological and anatomical study--case report.

Abstract

We examined a patient who had signs of a cerebral hemisphere lesion: right hemiparesis, facial weakness, right hemianopsy, acustico-mnestic dysphasia, "empty speech," acalculia, visuo-spatial agnosia and constructional apraxia, but without changes in consciousness. Taking into account clinical signs, computed tomography and carotid angiography findings, we concluded that our patient had an infarction zone in the left temporo-parieto-occipital region, as a consequence of the isolated angular gyri artery (ANG) occlusion. Some clinical signs were a direct effect of the ANG's occlusion. Namely, this artery supplies the cortical regions of great functional significance: the planum polare and temporale, the transverse temporal gyri, the superior and middle temporal gyri, the angular and supramarginal gyri, as well as the superior, middle and inferior occipital gyri. But the other symptoms and signs could be explained by the pathophysiological effect of the cerebral edema on regions supplied by the non-occluded branches of the middle cerebral artery.

Digital Probabilistic Atlas of the Border Region between the Middle and Posterior Cerebral Arteries

“…Branches of the MCA (anterior and/or posterior parietal arteries or the angular artery) supply regions within the ‘traditional’ posterior external borderzone. It is possible that occlusion of these vessels gives rise to infarcts which are thought to be borderzone infarcts [34,35,36]. The anterior parietal artery supplies the antero-superior part of the post-central gyrus and the superior parietal lobule [35, 37, 38].…”

“…The posterior parietal artery supplies the supramarginal gyrus and postero-superior part of the parietal lobe [35, 37]. The angular artery supplies the angular gyrus and the caudal part of the superior and middle temporal gyri [35,36,37,38]. The temporo-occipital artery supplies the posterior half of the superior temporal gyrus, the posterior part of the middle and inferior temporal gyri, and the inferior parts of the lateral occipital gyri.…”

Anatomical variations of artery of angular gyrus

“…In the case of the division into two final branches, superior branch ends in intraparietal sulcus (25%), transverse occipital sulcus (30%), superior and inferior temporal gyrus (40%) or inferior temporal gyrus (5%); inferior branch ends in lunate sulcus (25%), superior temporal gyrus (5%) or middle and inferior temporal gyrus (70%). [13] Ring, B. A. study showed that inferior branch of AGA ended 1 to 3 centimetres away from occipital pole dorsally in 42% of 34 telencephalons.…”

“…[12] In least common cases, AGA has the same diameter as the temporooccipital and the posterior parietal artery, and rarely, a smaller diameter than aforementioned vessels. [13] Generally, AGA appears as a singular branch (88%), seldom as two separate branches (12%) of MCA. Near the angular gyrus or directly below, AGA often (63%) divides into two final branches: superior and inferior; less often (21%) into three or four final branches or no branches at all (16%).…”

“…[14] Based on this research it was established that AGA supplies areas 17, 18, 19, 22, 37, 39, 40, 41, 42 and 52, and temporoparietal region (areas 22, 37, 39) is the middle part of the vascular territory of AGA. [13] Usually, AGA and posterior occipital artery start at the similar place at MCA-according to one study [14] either both leave MCA as a joint trunk (52%) or as separate branches divided by fissure (32%) or remain undivided (4%). Alternative possibilities are less common (12%).…”