Membrana de Liliequist: avaliação radiológica e suas implicações clínicas e terapêuticas

Abstract

In a simplistic and succinct way, Liliequist membrane may be understood as a projection formed by an arachnoid membrane extending from the dorsum sellae to the mammillary bodies. In spite of being well known to neurosurgeons, many radiologists neither know this anatomical structure nor give importance to its study. The imaging evaluation of this membrane is feasible and may be interesting for a better preoperative planning; postoperative evaluation of third ventriculostomies; and understanding of suprasellar arachnoid cysts and perimesencephalic hemorrhage. The present article illustrates the anatomy of the membrane, with emphasis on imaging findings, besides describing its possible clinical and surgical implications.

Neuroradiological Correlation of the Lateral Third Periventricular, Pituitary Gland and Stalk, Pineal Gland, Cerebral Aqueduct, and Foramen Magendie and Luschka With Intraventricular Neuroendoscopic Images: A Case Series

“…Dias et al illustrated the anatomy of the Liliequist membrane in relation to imaging findings [ 16 ]. The three segments, i.e., the sellar, mesencephalic, and diencephalic, lie beneath the third ventricle, anteriorly extending from the dorsum sellae to the mammillary bodies [ 17 ].…”

“…In clinical cases such as a child with ventriculitis (Figure 3 ), the thickened floor of the third ventricle is well visualized during the ETV procedure, even though the radiological image cannot be appreciated. The leaflets of the Liliequist membrane (Figure 5 ) also vary, and during the formation of a stoma, the membrane may or may not adhere to the floor of the ventricle [ 16 ].…”

Chiari III malformation with defect in Liliequist membrane on MR imaging

“…Lateral attachments of the membrane are to the arachnoid sheath adjacent to oculomotor nerves. [ 2 , 8 ]…”

Endoscopic Third Ventriculostomy in the Pediatric Patient

“…Originally described by Key and Retzius in 1875, and after described by Liliequist in 1956 [13,14] is an arachnoid membrane separating the chiasmatic cistern, interpeduncular cistern and prepontine cistern. It arises anteriorly from the diaphragma sellae and extends posteriorly separating into two sheets, The membrane of Liliequist is a partially trabecular, partially dense folded inner arachnoid membrane, and a very important anatomic landmark in the anatomy of the interpeduncular fossa and sellar and parasellar regions [15].…”