Thefalx cerebri(also known as thecerebral falx) is a large, crescent-shaped fold ofdura materthat descends vertically into thelongitudinal fissureto separate thecerebral hemispheres.[1]It supports thedural sinusesthat providevenousandCSFdrainage from thebrain.[2]It is attached to thecrista gallianteriorly, and blends with thetentorium cerebelliposteriorly.[3]

Falx cerebri
Dura materand its processes exposed by removing part of the right half of theskulland thebrain.
Diagrammatic representation of a section across the top of the skull, showing the membranes of the brain, etc. (Falx cerebri is yellow line running down center.)
Details
Part ofMeninges
Identifiers
Latinfalx cerebri
NeuroNames1237
TA98A14.1.01.103
TA25374
FMA83967
Anatomical terms of neuroanatomy

The falx cerebri is often subject to age-related calcification, and a site of falcine meningiomas.[2]

The falx cerebri is named for itssickle-like shape.[4]

Anatomy

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The falx cerebri is a strong, crescent-shaped sheet ofdura materlying in the sagittal plane between the twocerebral hemispheres.[3]It is one of fourdural partitionsof the brain along with thefalx cerebelli,tentorium cerebelli,anddiaphragma sellae;it is formed through invagination of the dura mater into thelongitudinal fissurebetween the cerebral hemispheres.[2]

Anteriorly, the falx cerebri is narrower, thinner, and may have a number of perforations. It is broader posteriorly.[3]

Attachments

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The falx cerebri attaches anteriorly at thecrista galli(proximally to thecribriform plateand to thefrontalandethmoid sinuses).[1]

Posteriorly, it blends into the upper surface of thecerebellar tentorium.[3]

Its convex superior margin is attached to the internal surface of the skull on either side of the midline. This attachment runs as far back as theinternal occipital protuberance(the latter representing its posterior-most point of attachment[2]); the superior sagittal sinus runs in the cranial groove between the falx cerebri's two attachments.[3]

The (concave) inferior margin of the falx cerebri is free.[3]

Vascular supply

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The falx cerebri receives its blood supply primarily from two vessels; the anterior portion receives blood supply from the anterior meningeal artery (a.k.a. anterior falx artery, or anterior falcine artery) (a branch of the anterior ethmoidal artery), and the posterior portion from the posterior meningeal artery (a branch of the ascending pharyngeal artery).[2]

Lymphatic drainage of the falx cerebri occurs mostly via meningeal lymphatic vessels that run parallel to the dural sinuses and that eventually exit the cranial vault through the jugular foramen to empty into deep cervical lymph nodes. A minority of lymph from the falx cerebri is drained anteriorly through the cribiform plate into the lymphatics of the nasal mucosa.[2]

Innervation

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The falx cerebri receives innervaton from all three branches of the trigeminal nerve. It receives symphatetic innervation predominantly from the superior cervical ganglia. It may receive additional innervation from dorsal rami of CN 1 and CN 2, the hypoglossal nerve, and recurrent branches of the vagus nerve.[2]

Anatomical relations

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The falx cerebri is situated in the longitudinal fissure, in between the cerebral hemispheres.[3]Thecorpus callosumlies immediately inferior to the lower (free) margin of falx cerebri.[2]

Dural venous sinuses

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Thesuperior sagittal sinusis contained in the superior margin of the falx cerebri and overlies the longitudinal fissure of the brain.[1]

Theinferior sagittal sinusis contained in the inferior[1]free[3]margin of the falx cerebri and arches over thecorpus callosum,deep within the longitudinal fissure.[1]

Thestraight sinuscourses along the juncture of the falx cerebri and cerebellar tentorium.[3]

Anatomical variation

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Total or partialagenesisof the falx cerebri may occur, and may result in adherence of the cerebral hemispheres across the midline. Agenesis is usually associated with other developmental complications; falx cerebri agenesis in absence of other neural symptoms is exceedingly rare.[2]

Microanatomy

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The falx cerebri contains blood vessels, and nerves.[2]

Clinical significance

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Calcification

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Calcification of the falx cerebri is more prevalent in older patients, often without a determinable cause, and without pathogenic symptoms.[5]

Meningioma

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Falcine meningioma is ameningiomaarising from the falx cerebri and completely concealed by the overlying cortex. Falcine meningioma tends to grow predominantly into one cerebral hemisphere but is often bilateral, and in some patients the tumor grows into the inferior edge of the sagittal sinus. However, although much information is available regarding meningiomas, little is known about falcine meningiomas.[6]

Surgical landmark

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The falx cerebri is a significant surgical landmark for access of the lateral ventricles via the interhemispheric transcallosal approach;agenesis(complete or partial) of the falx cerebri results in the adherence of the cerebral hemispheres, blocking midline transcallosal surgical access to the ventricles.[2]

Subfalcine brain herniation

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Subfalcineherniationof thecingulate gyrusmay occur followingtraumatic brain injury.[2]

Additional images

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See also

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References

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This article incorporates text in thepublic domainfrompage 873of the 20th edition ofGray's Anatomy(1918)

  1. ^abcdeSaladin K. "Anatomy & Physiology: The Unity of Form and Function. New York: McGraw Hill, 2014. Print. pp 512, 770-773
  2. ^abcdefghijklBair, Michael M.; Munakomi, Sunil (2022),"Neuroanatomy, Falx Cerebri",StatPearls,Treasure Island (FL): StatPearls Publishing,PMID31424888,retrieved2022-04-26
  3. ^abcdefghiStandring, Susan (2020).Gray's Anatomy: The Anatomical Basis of Clinical Practice(42th ed.). New York. p. 398.ISBN978-0-7020-7707-4.OCLC1201341621.{{cite book}}:CS1 maint: location missing publisher (link)
  4. ^"Falx".Retrieved10 August2024.
  5. ^Daghighi MH, Rezaei V, Zarrintan S, Pourfathi H (2007). "Intracranial physiological calcifications in adults on computed tomography in Tabriz, Iran."Folia Morphol (Warsz).66(2):115-9.PMID17594669
  6. ^Chung SB, Kim CY, Park CK, Kim DG, Jung HW (2007). "Falx Meningiomas: Surgical Results and Lessons Learned from 68 Cases."J Korean Neurosurg Soc.42 (4): 276-280.PMC2588203
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