4 Extraocular Muscles-Innervation-Vasculature_JC_2024_release.pdf

OPTM4102 Seminar 4: EOM, Ocular innervation and Vasculature Dr Jason Charng [email protected]  Acknowledgement of country The University of Western Australia acknowledges that its campus is situated on Noongar land, and t...

OPTM4102 Seminar 4: EOM, Ocular innervation and Vasculature Dr Jason Charng [email protected]  Acknowledgement of country The University of Western Australia acknowledges that its campus is situated on Noongar land, and that Noongar people remain the spiritual and cultural custodians of their land, and continue to practise their values, languages, beliefs and knowledge. Artist: Dr Richard Barry Walley OAM Objectives 1. Review function of the extraocular muscles 2. Identify EOM dysfunction via clinical cases 3. Discuss eye-specific (non-EOM) functions controlled by cranial nerves 4. Review the anatomy underlying blood supply to the eye 3 IR 1 #* Capitalisation Bowman’s/Descemet’s/Müller’s superior tarsal muscle 4 IR 1 Central retinal vein Central retinal artery Retinal venule Retinal arteriole Macula Fovea Optic disc Forea Vein 3 features artery vs vein? 5  blood cale through & , l coming nutrients. blockage & not + blood No orygen , IR 1 through coming - 6 a - central retina vain. but : 00 retina artery not 1 -. Which has worst vision prognosis? Why? - > No blood - coming through 6 Recap - Phoria inward outward orthophoria 7 Testing eye alignment 9 Extraocular Muscles 10 Part I Extraocular Muscles > - Kelletal muscle. EOM = Smooth muscle 7 EOM Miller muscle – Four Recti (LR,MR,SR,IR) – Two Obliques (SO,IO) – Levator palpebrae superioris FUNCTION? https://www.earthslab.com/anatomy/extraocular-muscles/ 11  unison all working together working Patient's right eye ,. avoid double vision Optic Nerve - - Heat to the nose https://en.wikipedia.org/wiki/Extraocular_muscles 12. movement twisting Trochlea Annulus of Zinn ↑ Muscle Origin Insertion Eye Medial rectus Annulus of Zinn (anterior, medial surface) Eye Lateral rectus Annulus of Zinn (anterior, lateral surface) Eye Superior rectus Annulus of Zinn (anterior, superior surface) Eye Inferior rectus Annulus of Zinn (anterior, inferior surface) Eye Sphenoid bone Superior oblique (posterior, superior, via the Trochlea lateral surface) Eye Inferior oblique Maxillary bone (posterior, inferior, lateral surface) Levator palpebrae Tarsal plate of Sphenoid bone superioris upper eyelid 13 Part I Extraocular Muscles Right eye. EOM: Eye Movements Pt’s R or L eye? Ductions - are monocular eye movements Where’s nose? towards nose Nasally/Medially = Adduction => moving Temporally/Laterally = Abduction 8 f Elevation = Supraduction up Depression = Infraduction down - Incycloduction (Intorsion) = nasal rotation of the next upper vertical meridian => rotating towards the nose to the nose Excycloduction (Extorsion) = temporal rotation of - the upper vertical meridian => rotating away from the nose. https://www.earthslab.com/anatomy/extraocular-muscles/ 14 Part I Extraocular Muscles EOM Versions are movements of both eyes in the same direction (eg, right gaze in which both eyes move to the right) Nasal or temporal in Dextroversion is movement of both eyes to the patient’s right RE and LE? Levoversion is movement of both eyes to the patient’s left Supraversion (sursumversion) elevation of both eyes infraversion (deorsumversion) are depression of both eyes Which eye is right/left? Which image is dextroversion? -- https://emedicine.medscape.com/article/1189759-overview 15 Part I Extraocular Muscles EOM Vergences are movements of both eyes in the opposite direction Convergence is movement of both eyes nasally E both inwards O Divergence is movement of both eyes temporally => both outwards. Vertical vergence movements may also occur (ie, one eye moving upward or the other eye moving downward) sth close. E When do the eyes converge? when looking E When do the eyes diverge? close things move When 16 further - Extraocular Muscles Actions 17 Part I Extraocular Muscles EOM: Horizontal Eye Movements * Need to remember Muscle Primary action Secondary action Tertiary action. ISOLATE muscle dysfunction Medial rectus Adduction Adduction Lateral rectus Abduction Superior rectus Elevation Incyclotorsion Adduction O Inferior rectus Depression Excyclotorsion Adduction Superior oblique Incyclotorsion Depression Abduction Abduction Abduction Inferior oblique Excyclotorsion Elevation Abduction Acting as INDEPENDENT muscle 18 Part I Extraocular Muscles 19 www.aao.org Part I Extraocular Muscles EOM: Horizontal Eye Movements Muscle Primary action Secondary action Tertiary action Medial rectus Adduction Adduction Lateral rectus Abduction Incyclotorsion/ Superior rectus Elevation Adduction Intorsion Excyclotorsion/ Inferior rectus Depression Adduction Extorsion Superior oblique Incyclotorsion Depression Abduction Abduction Abduction Inferior oblique Excyclotorsion Elevation Abduction 20 Part I Extraocular Muscles EOM: Vertical Eye Movements Muscle Primary action Secondary action Tertiary action Medial rectus Adduction Elevation Lateral rectus Abduction Superior rectus Elevation Incyclotorsion Adduction Inferior rectus Depression Excyclotorsion Adduction Superior oblique Incyclotorsion Depression Abduction Depression Inferior oblique Excyclotorsion Elevation Abduction 21 Part I Extraocular Muscles EOM: Rotational Eye Movements Muscle Primary action Secondary action Tertiary action Medial rectus Adduction Lateral rectus Abduction Superior rectus Elevation Incyclotorsion Adduction Inferior rectus Depression Excyclotorsion Adduction Superior oblique Incyclotorsion Depression Abduction SO Incyclotorsion Inferior oblique Excyclotorsion Elevation Abduction Direction R Clockwise L Anticlockwise 22 Part I Extraocular Muscles EOM: Rotational Eye Movements Muscle Primary action Secondary action Tertiary action Medial rectus Adduction Lateral rectus Abduction Superior rectus Elevation Incyclotorsion Adduction Inferior rectus Depression Excyclotorsion Adduction Superior oblique Incyclotorsion Depression Abduction SO Incyclotorsion Inferior oblique Excyclotorsion Elevation Abduction Direction R Anticlockwise L Clockwise 23 Part I Extraocular Muscles EOM: Rotational Eye Movements Muscle Primary action Secondary action Tertiary action Medial rectus Adduction Lateral rectus Abduction Superior rectus Elevation Incyclotorsion Adduction Inferior rectus Depression Excyclotorsion Adduction Superior oblique Incyclotorsion Depression Abduction SO Incyclotorsion Inferior oblique Excyclotorsion Elevation Abduction Direction R Clockwise L Anti clockwise 24 Part I Extraocular Muscles EOM: Eye Movements RECAP Torsion Muscle Primary action Secondary action Tertiary action Abduction Abduction Medial rectus Adduction Adduction Lateral rectus Abduction Elevation Superior rectus Elevation Incyclotorsion Adduction Inferior rectus Depression Excyclotorsion Adduction Depression Superior oblique Incyclotorsion Depression Abduction Inferior oblique Excyclotorsion Elevation Abduction Acting as INDEPENDENT muscle ISOLATE muscle dysfunction 25 Agonist and Antagonist Muscles 26 Agonistic and Antagonistic muscles The primary muscle that moves an eye in a given direction is known as the agonist A muscle in the same eye that ASSIST the eye in the same direction as the agonist is known as the synergist A muscle in the same eye that moves the eye in the opposite direction of the agonist is the antagonist Sherrington law: increased innervation to any muscle (agonist) is accompanied by a corresponding decrease in innervation to its antagonists https://emedicine.medscape.com/article/1189759-overview 27  38 30 : - 39 Agonistic and Antagonistic muscles 48 49 Yoke muscles are the primary muscles in each eye that accomplish : a given gaze (eg, for right gaze, the right lateral rectus and left medial rectus muscles) Each extraocular muscle has a yoke muscle in the opposite eye to accomplish versions into each gaze position double vision... - Hering law: yoke muscles receive equal and simultaneous No overshoot innervation 2 3 1 4 6 5 https://emedicine.medscape.com/article/1189759-overview 28 The primary muscle that moves an eye in a given direction is known as the agonist A muscle in the same eye that ASSIST the eye in the same direction as the agonist is known as the synergist Agonistic and Antagonistic muscles - Example Looking UP and RIGHT (superior right gaze) requires 1. Vertical muscles: RAgonists SR + L (Yoke IO (Elevation) Muscles) R SR L10 (elevation)Muscle + Primary Secondary Tertiary action action action R IO + L SR(upgaze) Synergists Medial rectus Adduction Lateral rectus Abduction Superior rectus Elevation Incyclotorsion Adduction Inferior rectus Depression Excyclotorsion Adduction Superior Incyclotorsion Depression Abduction oblique Inferior oblique Excyclotorsion Elevation Abduction 29 A muscle in the same eye that moves the eye in the opposite direction of the agonist is the antagonist Agonistic and Antagonistic muscles - Example Looking UP and RIGHT (superior right gaze) requires - Primary Secondary Tertiary 2. Antagonist muscles: Muscle action action action O nfetio - (mar muscles. Medial rectus Lateral rectus Adduction Abduction - Superior rectus Elevation Incyclotorsion Adduction Y Inferior rectus Depression Excyclotorsion Adduction Superior Incyclotorsion Depression Abduction oblique Inferior oblique Excyclotorsion Elevation Abduction 30 EOM Innervations 31  Lib : 20 Certain E... Muscle Innervation Medial rectus Oculomotor nerve Cranial Nerves III, IV, VI (inferior branch) (Motor Nerves) ↳ Lateral rectus Abducens nerve Oculomotor nerve Superior rectus (superior branch) Oculomotor nerve Inferior rectus (inferior branch) Superior oblique Trochlear nerve Oculomotor nerve Inferior oblique (inferior branch) Levator palpebrae Oculomotor nerve superioris Abducens, CN? Trochlear, CN? Oculomotor, CN? 32 33  Ocular Motility Testing ‘H Pattern’ 9 Cardinal Gaze Positions https://morancore.utah.edu/basic-ophthalmology- review/the-motility-exam/ 34 EOM Mini QUIZ 35 EOM abnormalities O bit in a pointing O Not pointing L to the right it should as be D Not parallel direction. D O 1. Which EOM/EOMs affected? ↓ not pointing at the nose 2. What could be underlying cause? i.e of right medial rectus. reaction well Right lateral rectus not working , 57 : So EOM abnormalities a b c O d Oe O f g h O i 1. Which EOM/EOMs affected? is 2. What could be underlying cause?  EOM abnormalities a O b c O d e f g h i 1. Which EOM/EOMs affected? 2. What could be underlying cause? home Take : 660 message  EOM abnormalities Besides eye Gog a b size , dilate pupil , c G O eyelid C misalignment, what abnormalities d e f can you also Coc note? g h i 1. Which EOM/EOMs affected? 2. What could be underlying cause? Ocular Innervations 40  Six cranial nerves innervate motor (M), sensory (S), Trochlear (dorsal) and autonomic structures in the eyes The six cranial nerves are the optic nerve (CN II), S oculomotor nerve (CN III), M trochlear nerve (CN IV), M trigeminal nerve (CN V) 1st Division Ophthalmic, S abducens nerve (CN VI), M facial nerve (CN VII), S and M https://in.pinterest.com/pin/572872015097421985/ https://www.ncbi.nlm.nih.gov/books/NBK549919/ 41  PAIRED https://teachmeanatomy.info/head/cranial-nerves/summary/ 42 Cavernous Sinus www.aao.org Travels through lateral wall of Travels through cavernous sinus: cavernous sinus: Abducens nerve (CN VI) Oculomotor nerve (CN III) Carotid plexus (post-ganglionic Trochlear nerve (CN IV) sympathetic nerve fibres) Ophthalmic (V1) and maxillary (V2) Internal carotid artery (cavernous branches of the trigeminal nerve portion) 43  CN III 74 - : - 00 R CN II CN IV allows.... O CN V(I) to travel -- CN VI from.. L https://3d4medical.com/blog/innervation-of-the-eye https://en.wikipedia.org/wiki/Superior_orbital_fissure 44 Sympathetic Nervous System MYDRIASIS 1 & dilation Pupil signal L Function?? ↓ 3 2 B/w C8 and T2 https://www.ncbi.nlm.nih.gov/books/NBK549919/ https://www.aao.org/image/sympathetic-pathway-3 45 Parasympathetic nervous system MIOSIS ↳ pupil construction MIDBRAIN CN3 Short ciliary nerve Iris sphincter muscle 46 www.aao.org Ocular Vasculatures 47 Ophthalmic Vasculature of retina outter portion = Supplies ~ photorecepter Blood supply to the eye inner portion supplies of retina - ↑ Central retinal artery opthalmic artery posterior - - ciliary Optic nerve internal carotid artery - - lacrimal --- 48 Part II Ophthalmic Vasculature Inner retina veinous return superior Ophthalmic cavernous sinus Vortex Vein 49 Part II Ophthalmic Vasculature Choroid drainage Vortex Vein 50 Part II Ophthalmic Vasculature drains into Conjunctival drainage > - into Drains > cavernous sinus 51 RECAP 52 Part I Extraocular Muscles EOM: RECAP 7 EOMs (6 eye movement, 1 non movement) Four recti (LR,MR,SR,IR) Two obliques (SO,IO) EOM Actions https://www.earthslab.com/anatomy/extraocular-muscles/ 53 Part I Extraocular Muscles EOM: RECAP Muscle Innervation Origin Insertion Primary action Secondary action Tertiary action Oculomotor nerve Eye Medial rectus Annulus of Zinn Adduction (inferior branch) (anterior, medial surface) Eye Lateral rectus Abducens nerve Annulus of Zinn Abduction (anterior, lateral surface) Eye Oculomotor nerve Superior rectus Annulus of Zinn (anterior, superior Elevation Incyclotorsion Adduction (superior branch) surface) Eye Oculomotor nerve Inferior rectus Annulus of Zinn (anterior, inferior Depression Excyclotorsion Adduction (inferior branch) surface) Eye Sphenoid bone Superior oblique Trochlear nerve (posterior, superior, Incyclotorsion Depression Abduction via the Trochlea lateral surface) Eye Oculomotor nerve Inferior oblique Maxillary bone (posterior, inferior, Excyclotorsion Elevation Abduction (inferior branch) lateral surface) Levator palpebrae Tarsal plate of Elevation/retractionof Oculomotor nerve Sphenoid bone superioris upper eyelid the upper eyelid 54