Uncus Of The Human Brain, Medial View

Description

Uncus anatomy dominates the anteromedial temporal lobe, curving like a hook at the anterior end of the parahippocampal gyrus on the medial surface of the cerebrum. From this fixed medial perspective, the uncus sits inferior to the anterior part of the hippocampal formation and immediately anteroinferior to the amygdaloid complex, with the parahippocampal gyrus extending posteriorly toward the isthmus of the cingulate gyrus. Medially and superiorly, the adjacent basal forebrain and diencephalic contours frame the region, while the tentorial edge and ambient cistern occupy the nearby subarachnoid space around the medial temporal lobe. Small, crowded anatomy. Uncal relationships matter because this is the medial temporal landmark that defines the classic compression pattern in transtentorial (uncal) herniation, where the medial temporal lobe is forced against the tentorial notch and can distort the midbrain. In that setting, clinicians watch for ipsilateral oculomotor nerve (CN III) compression with a dilated pupil, posterior cerebral artery compromise with occipital infarction, and brainstem distortion with declining consciousness, all tied to the uncus sitting directly adjacent to the tentorium and perimesencephalic cisterns. The medial viewpoint supports teaching by keeping the uncus anchored to the parahippocampal gyrus and nearby limbic structures, reducing ambiguity when students confuse it with the hippocampal head or the amygdala on cross-sectional imaging. Neuroanatomy faculty can place this illustration into limbic system modules to orient the parahippocampal gyrus, amygdala, and hippocampal head before correlating to MRI of mesial temporal sclerosis and epilepsy surgery planning. It also fits neurosurgical and emergency medicine teaching on herniation syndromes, where the uncus is the named culprit and the tentorial incisura is the operative landmark. Anatomical accuracy verified by SciePro's Medical Advisory Board.