fornix


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fornix

 [for´niks] (pl. for´nices) (L.)
an anatomical archlike structure.
fornix of conjunctiva conjunctival cul-de-sac.

for·nix

, gen.

for·ni·cis

, pl.

for·ni·ces

(fōr'niks, -ni-sis, -ni-sēz), [TA] Do not confuse this word with pharynx.
1. In general, an arch-shaped structure; often the arch-shaped roof (or roof portion) of an anatomic space.
2. The compact, white fiber bundle by which the hippocampus of each cerebral hemisphere projects to the contralateral hippocampus and to the septum, anterior nucleus of the thalamus, and mammillary body. Arising from pyramidal cells of the Ammon horn, the fibers of the fornix form the alveus hippocampi and the fimbria hippocampi, and in their further course compose, sequentially, the commissure of the fornix [TA], also called the hippocampal commissure [TA] (commissura hippocampi [TA]), the crus of fornix [TA] (crus fornicis [TA]), the body of fornix [TA] (corpus fornicis [TA]), and the column of fornix [TA] (columna fornicis [TA]), which divides into a smaller portion of precommissural fibers [TA] that pass anterior to the anterior commissure to the septal area and a larger portion of postcommissural fibers [TA] that pass posterior to the anterior commissure to end mainly in the mammillary nuclei and to a lesser extent in the anterior thalamic nucleus. Synonym(s): trigonum cerebrale
Synonym(s): cerebral trigone
[L. arch, vault]

fornix

/for·nix/ (for´niks) pl. for´nices   [L.]
1. an archlike structure or the vaultlike space created by such a structure.
2. fornix of brain; either of a pair of arched fiber tracts that unite under the corpus callosum, so that together they comprise two columns, a body, and two crura.

fornix

(fôr′nĭks)
n. pl. for·nices (-nĭ-sēz′)
An archlike anatomical structure or fold, such as the arched band of white matter beneath the corpus callosum of the brain.

fornix

[fôr′niks] pl. fornices
Etymology: L, arch
an archlike structure or space, such as the fornix cerebri, the superior or inferior conjunctival fornices, or the vaginal fornices.

for·nix

, gen. fornicis, pl. fornices (fōr'niks, -ni-sis, -sēz)
1. [TA] In general, an arch-shaped structure; often the arch-shaped roof (or roof portion) of an anatomic space.
2. The compact, white fiber bundle by which the hippocampus of each cerebral hemisphere projects to the contralateral hippocampus and to the septum, anterior nucleus of the thalamus, and mammillary body. Arising from pyramidal cells of Ammon's horn, the fibers of the fornix form the alveus hippocampi and the fimbria hippocampi, and in their further course compose, sequentially, the commissure of the fornix, also called the hippocampal commissure (commissura hippocampi [TA]), the crus of fornix (crus fornicis [TA]), the body of fornix (corpus fornicis [TA]), and the column of fornix (columna fornicis [TA]), which divides into a smaller portion of precommissural fibers that pass anterior to the anterior commissure to the septal area and a larger portion of postcommissural fibers that pass posterior to the anterior commissure to end mainly in the mammillary nuclei and to a lesser extent in the anterior thalamic nucleus.
[L. arch, vault]

fornix

An arch, especially one of the pair of arch-like bands of white fibres lying under the corpus callosum of the brain, or the space between the upper walls of the vagina and the neck of the womb.

conjunctiva 

A thin transparent mucous membrane lining the posterior surface of the eyelids from the eyelid margin and reflected forward onto the anterior part of the eyeball where it merges with the corneal epithelium at the limbus. It thus forms a sac, the conjunctival sac, which is open at the palpebral fissure and closed when the eyes are shut. The depths of the unextended sac are 14-16 mm superiorly and 9-11 mm inferiorly. The conjunctiva is divided into three portions: (1) The portion that lines the posterior surface of the eyelids is called the palpebral conjunctiva. It is itself composed of the marginal conjunctiva, which extends from the eyelid margin to the tarsal conjunctiva; the tarsal conjunctiva, which extends from the marginal conjunctiva to the orbital conjunctiva; and the orbital conjunctiva, which extends from the tarsal conjunctiva to the fornix. (2) That lining the eyeball is the bulbar conjunctiva. It is itself composed of the limbal conjunctiva, which is fused with the episclera at the limbus and the scleral conjunctiva, which extends from the limbal conjunctiva to the fornix. (3) The intermediate part forming the bottom of the conjunctival sac, unattached to the eyelids or the eyeball and joining the bulbar and the palpebral portion is called the fornix (conjunctival fold, cul-de-sac). See dyskeratosis; lid eversion; conjunctival gland; Krause's end bulbs; subtarsal sulcus.

fornix

pl. fornices [L.] an archlike structure or the vaultlike space created by such a structure.

cerebral fornix
either of a pair of arched fiber tracts that unite under the corpus callosum, so that together they comprise two columns, a body, and two crura.
conjunctival fornix
line of reflexion of the conjunctiva from the eyelid to the eyeball.
hippocampal fornix
a thick bundle of nerve fibers leaving the hippocampus to enter the hypothalamus, terminating in the mamillary body.
telencephalic fornix
see cerebral fornix (above).
vaginal fornix
the annular recess around the outside of the cervix.
References in periodicals archive ?
Hippocampal glucose metabolism in mice was examined by microdialysis in vivo as follows: aged mice with fornix stimulation ( n = 12), adult mice with fornix stimulation ( n = 12), aged mice with fornix sham-stimulation ( n = 8), and adult mice with fornix sham-stimulation ( n = 8).
While most of the clinical studies cited included teeth with Glickman grade I and II furcation involvement, this study sample was limited to mandibular teeth with radiographically detectable furcation involvement apical to the furcation fornix.
sup][6] The flap created by the proposed procedure connects the upper fornix and the lower lid margin and transmits the supraduction force from the upper fornix into an upward force to raise the lower lid.
Bannowsky, "Iatrogenic fornix rupture caused during retrograde manipulation of the ureter: a case report," Cases Journal, vol.
Conclusion: Endoscopic surgery is superior to conventional nasal packing for the management of epistaxis in the posterior fornix of the inferior nasal meatus.
A drop of local anesthetic agent (tetracane) was gently instilled into the lower fornix of the subject.
ADvance is a randomised, double blind, controlled trial of 42 patients age 45 to 85 with mild Alzheimer's disease to evaluate the potential clinical benefit and safety of DBS of the fornix, a major inflow and output pathway in the brain's memory circuit.
9) The suggested mechanism for the urine extravasation includes rupture of the calyceal fornix secondary to rapidly increasing intrapelvic pressures, with extravasated urine being re-absorbed by either the venous or lymphatic routes.
Several types of bacteria were isolated with aerobic culture of the conjunctival fornix (Table 3).
Diagnosis of PROM was confirmed by visual pooling of clear fluid in the posterior fornix of the vagina or leakage of fluid from the cervical os on sterile speculum examination.
Axial T2-weighted images with fluid attenuated inversion recovery (FLAIR) at the level of the basal ganglia showed an increased signal of the fornix and periventricular region around the third ventricle and the medial thalamic nuclei.