AC: anterior clinoid process; ICA: internal carotid artery; LT: lamina terminalis; ON: optic nerve; OlN; olfactory nerve; SW: sphenoid wing; TS: tuberculum sellae; A1: A1 segment of the Anterior Cerebral Artery; A2: A2 segment of the Anterior Cerebral Artery; M1: M1 segment of the Middle Cerebral Artery
The median portion of the wall of the fore-brain vesicle consists of a thin lamina, the lamina terminalis, which stretches from the interventricular foramen (Foramen of Monro) to the recess at the base of the optic stalk and contains the organum vasculosum of the lamina terminalis, which regulates the osmolarity of the blood.
Access to the third ventricle can be achieved through the lamina terminalis corridor. A skull base approach to the lamina terminalis can be performed using either an anterolateral approach (orbitozygomatic, pterional, supraorbital) or a midline approach (extended transbasal approach, subfrontal).
Signals detected by taste receptors, peripheral osmo-sodium, volume receptors, and arterial/cardiopulmonary baroreceptors reach the nucleus of the solitary tract (NTS) by the VIIth, IXth, and Xth cranial nerves. The other main brain entry of the information related to fluid and cardiovascular balance are the lamina terminalis (LT) and one of the sensory circumventricular organs (CVOs), the area postrema (AP).
The LT, consisting of the median preoptic nucleus (MnPO) and the other two sensory CVOs—i.e., subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT) —is recognized as a site in the brain that is crucial for the physiological regulation of hydroelectrolyte balance.