Orbit and eye Flashcards
Extrinsic muscles of the eye?
Superior rectus Medial rectus Inferior rectus Lateral rectus Superior oblique Inferior oblique Levator palpebrae superioris
Extrinsic muscle which does not insert onto the eye?
Levator palpebrae superioris
Innervation of lateral rectus?
Abducent nerve
Innervation of superior oblique?
Trochlear nerve
Innervation of superior rectus muscle?
Oculomotor
Innervation of inferior oblique muscle?
Oculomotor
Bones forming the orbit?
Frontal Ethmoid Sphenoid Lacrimal Zygomatic Maxillary
Main contents of the orbit?
The eyeball Extrinsic muscles of the eye Cranial nerves III, IV, VI and branches of trigeminal nerve Orbital fat Branches of internal carotid artery Lacrimal apparatus Ligaments supporting the eye
Three layers of the eye?
Outer fibrous layer
Middle vascular layer
Internal sensory layer
Components of fibrous layer?
Sclera (white of the eye)
Cornea
Components of vascular layer?
Choroid
Ciliary body
Iris
Structure dividing eye into anterior and posterior segment?
Crystalline lens
Fluid filling anterior segment of the eye?
Aqueous humour
Fluid filling posterior segment of the eye?
Vitreous humour
Subdivisions of anterior segment of the eye?
Anterior chamber
Posterior chamber
Structure producing aqueous humour?
Ciliary body
Function of aqueous humour?
Maintaining intraocular pressure
Intraocular pressure?
21mmHg
Function of vitreous humour?
Cushions the retina
Intrinsic muscles of the eye?
Ciliaris
Constrictor pupillae
Dilator pupillae
Structures preventing over-adduction or over-abduction of the eye?
Medial and lateral check ligaments
Structure formed by blending of medial and lateral check ligaments with fascia of inferior extrinsic muscles?
Suspensory ligament of the eye
Ophthalmic artery is a branch of?
Internal carotid artery
Main blood supply to eye and orbit?
Ophthalmic artery
Cranial nerves present in orbit?
Optic nerve (II) Oculomotor nerve (III) Trochlear nerve (IV) Abducent nerve (VI) Ophthalmic and maxillary branches of trigeminal nerve (V)
Extrinsic muscle of the eye which does not originate from the posterior aspect of the orbit?
Inferior oblique
Branch of ophthalmic artery which supplies inner retina?
Central retinal artery
Anterior border of the retina?
Ora serrata
Foramina at the apex of the orbit?
Optic foramen
Superior orbital fissure
Inferior orbital fissure
Structures passing through optic foramen?
Optic nerve
Ophthalmic artery
Cranial nerves passing through superior orbital fissure?
Oculomotor
Trochlear
Abducent
Ophthalmic branch of trigeminal nerve
Structure passing through inferior orbital fissure?
Maxillary branch of trigeminal nerve