paralytic strabismus

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PARALYTIC STRABISMUS. Assist.Prof. Dr.Vildan ztrk Ophthalmology Yeditepe University Hospital. STRABISMUS. Strabismus involves deviation of the alignment of one eye in relation to the other. Non-paralytic strabismus Paralytic strabismus. concomitant strabismus; - PowerPoint PPT Presentation

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  • PARALYTIC STRABISMUS

    Assist.Prof. Dr.Vildan ztrkOphthalmologyYeditepe University Hospital

  • STRABISMUS

    Strabismus involves deviation of the alignment of one eye in relation to the other.

    Non-paralytic strabismus Paralytic strabismus

  • concomitant strabismus;due to faulty insertion of the eye muscles, resulting in the same amount of deviation regardless of the direction of the gazenonconcomitant strabismus; in which the amount of deviation of the squinting eye varies according to the direction of gaze

  • Strabismus=Squint, Wandering eye Esotropia=Crossed eyes Exotropia=Walleye

  • ANATOMYAnatomic axis Visual (optical) axisKappa angle:

  • ANATOMY OF EXTRAOCULAR MUSCLES:The lateral and medial walls of the orbit make an angle of 45 degrees with each other. In primary position the optical axis forms an angle of 22.5 degrees with the orbit.

  • ANATOMY OF EXTRAOCULAR MUSCLES:

    Primary action of the muscle is its major effect when the eye is in primary positionSubsidiary actions are the additional effects of the position of the eyeListing plane is an imaginary frontal equatorial plane passing through the center of rotation of globe. -The globe rotates left and right around the vertical Y axis -The globe moves up and down around the horizontal X axis. -Torsional movements occur around the Z axis which traverses the globe from front to back.

  • Z axisX azis Y axis

  • EYE MOVEMENTS Ductions are monocular eye movements around the axis of Fick. (X, Y, Z) Adduction; movement of the eye nasally Abduction; is temporal movement Supraduction; elevation Infraduction; depression of the eyeIncycloduction (intorsion); nasal rotation of the vertical meridianExcycloduction (extorsion); temporal rotation of the vertical meridian.

  • SIX CARDINAL POSITIONS OF GAZEUp / rightUp / leftRightLeftDown / rightDown / left

  • HORIZONTAL RECTUS MUSCLES:

    -Medial rectus: its action is adduction -Lateral rectus: its sole action is abduction.

  • VERTICAL RECTUS MUSCLES

    Superior rectus: primary action is elevationsecondary actions are adduction and intorsion Inferior rectus: primary action is depressionsecondary actions are adduction and extorsion

  • OBLIQUE MUSCLES Superior oblique muscle incyclotorsion. depressionabductionInferior oblique muscle excyclotorsionelevationabduction

  • Muscle Innervation Primary action Secondary action Tertiary action Medial rectus CN III Adduction -- -- Superior rectus CN III Elevation Intortion Adduction Inferior rectus CN III Depression Extortion Adduction Inferior oblique CN III Extorsion Elevation Abduction Superior oblique CN IV Intorsion Depression Abduction Lateral rectus CN VI Abduction -- --

  • Tillauxnun Spirali

  • LAWS OF OCULAR MOTILITYAgonist : the primary muscle that moves an eye in a given direction

    Synergist; muscle in the same eye that moves the eye in the same direction as the agonist

    Antagonist; muscle in the same eye that moves the eye in the opposite direction of the agonist muscle

    Sherrington Law, increased innervation to any muscle (agonist) is accompanied by a corresponding decrease in innervation to its antagonists.

  • LAWS OF OCULAR MOTILITYYoke muscles Primary muscles in each eye that accomplish a given version. Each extra ocular muscle has a yoke muscle in the opposite eye to accomplish versions into each gaze position.Herring Law; Yoke muscles receive equal and simultaneous innervation; Magnitude is determined by the fixating eye.

  • BINOCULAR EYE MOVEMENTSConjugate (versions) are movements of both eyes in the same direction -Dextroversion is movement of both eyes to the right, -Levoversion is movement of both eyes to the left. -Supraversion; elevation of both eyes, -Infraversion; depression of both eyes,

  • BNOCULAR EYE MOVEMENTSDisconjugate (vergences) are movements of the eyes in opposite directions. -Convergence is movement of both eyes nasally -Divergence is movement of both eyes temporally. -Vertical vergence movements also may occur.

  • TYPES OF STRABISMUS Esotropia is inward turning Exotropia is outward turning Hypertropia is upward turning Hypotropia is downward turning of the eye.

  • ESOTROPIA

  • EXOTROPIA

  • HYPERTROPIA

  • HYPOTROPIA

  • HIRSCHBERG TEST

  • DIPLOPIA

    Simultaneous appreciation of two images of one object. It results from a failure to maintain binocular vision.Binocular, monocular, physiological

  • MUSCLE INNERVATIONS

    medial rectus (MR)cranial nerve III lateral rectus (LR)cranial nerve VI superior rectus (SR)cranial nerve III inferior rectus (IR)cranial nerve III superior oblique (SO)cranial nerve IV inferior oblique (IO)cranial nerve III

  • Extra ocular muscle paralysis resulting from destructive lesions in one or all of these cranial nerves results in failure of one or both eyes to rotate in concert with the other eye.

  • (LR6SO4)3

  • OCULAR MOTOR NERVE PALSIES1. Third nerve2. Fourth nerve3. Sixth nerve

  • OCULOMOTOR (III.) NERVE PALSY The oculomotor nerve innervatessuperior rectus, inferior rectus, medial rectus, inferior oblique, levator palpebrae, ciliary muscle iris sphincter.

  • OCULOMOTOR (III.) NERVE PALSY

  • Anatomy of third nerveOculomotor nucleusPituitary glandCarotid arteryCavernous sinusIII nerveClivusBasilar arteryPost cerebral arteryRed nucleusPonsNuclear portion Fascicular portion intraparenchymal midbrain portionsubarachnoid portion cavernous sinus portion orbital portion

  • ANATOMYThe pupillomotor and ciliary muscle neurons derive from the Edinger-Westphal subnucleus, which is in the midline in the most rostral and anterior part of the oculomotor nerve nucleus. These autonomic pathways are all ipsilateral or uncrossed

    OCULOMOTOR (III.) NERVE PALSY

  • Applied anatomy of pupillomotor nerve fibresBlood vessels on pia mater supply surface of the nerve including pupillary fibres ( damaged by compressive lesions )Vasa nervorum supply partof nerve but not pupillaryfibres ( damaged by medicallesions )Pupillary fibres lie dorsal and peripheral

  • ETIOLOGYA- Pupil involving

    More common: Aneurysm ( particularly a post. communicating artery aneurysm)

    Less common: Ischemic microvascular disease ( DM or HT), tumour, trauma, congenital

    Rare: Uncal herniation, cavernous sinus mass lesion, pituatery apoplexy, orbital disease, herpes zoster, leukemia, in children ophthalmoplegic migraine OCULOMOTOR (III.) NERVE PALSY

  • ETIOLOGYB- Pupilsparing: Ischemic microvascular disease; rarely cavernous sinus syndrome, giant cell arteritis (GCA)C- Relative pupil-sparing: Ischemic microvascular disease; less likely aneurysm

    OCULOMOTOR (III.) NERVE PALSY

  • Etiology

  • Important causes of isolated third nerve palsyIdiopathic - about 25%Vascular disease - hypertension, diabetesPosterior communicating aneurysmTraumaExtraduralhaematomaProlapsingtemporallobeEdge oftentoriumAneurysmChiasmThird nervePosterior cerebralarteryMidbrainpushedacross

  • ETOLOGYNuclear and fascicular midbrain portionInfarctionHemorrhageNeoplasmAbscessOCULOMOTOR (III.) NERVE PALSY

  • ETIOLOGYFascicular midbrain portion infarctsBenedikt syndrome upper mid brain includes ipsilateral third cranial nerve palsycontralateral flapping hand tremor ataxiaWeber syndrome slightly more ventral lesion at the level of the third cranial nerve fascicles in the mid brainipsilateral third cranial nerve palsycontralateral hemiplegia or hemiparesis

    OCULOMOTOR (III.) NERVE PALSY

  • ETIOLOGYFascicular subarachnoid portionAneurysmInfectious meningitis - Bacterial, fungal/parasitic, viralMeningeal infiltrativeCarcinomatous / lymphomatous / leukemic infiltration, granulomatous inflammation (sarcoidosis, lymphomatoid granulomatosis, Wegener granulomatosis) OCULOMOTOR (III.) NERVE PALSY

  • ETIOLOGYFascicular cavernous sinus portionTumor - Pituitary adenoma, meningioma, craniopharyngioma, metastatic carcinoma Vascular Giant intracavernous aneurysmCarotid artery-cavernous sinus fistula Carotid dural branch-cavernous sinus fistula Cavernous sinus thrombosis Ischemia from microvascular disease in vasa nervosa Inflammatory - Tolosa-Hunt syndrome (idiopathic or granulomatous inflammation)OCULOMOTOR (III.) NERVE PALSY

  • ETIOLOGYFascicular orbital portionInflammatory, orbital inflammatory pseudotumor, orbital myositis Endocrine (thyroid orbitopathy) Tumor (hemangioma, lymphangioma, meningioma)OCULOMOTOR (III.) NERVE PALSY

  • FREQUENCY

    %30 of paralytic strabismus

    MORTALTY / MORBDTY subarachnoid hemorrhage from berry aneurysm of the posterior communicating arterymeningitis or meningeal infiltrative disorders, both infectious and neoplastic

    OCULOMOTOR (III.) NERVE PALSY

  • SYMPTOMSBinocular diplopia PtosisMydriasis With or without painOCULOMOTOR (III.) NERVE PALSY

  • Signs of right third nerve palsy Ptosis, mydriasis and cycloplegia Abduction in primary position Limited depression Limited adduction Normal abduction Limited elevation Intorsion on attempted downgaze

  • CRITICAL SIGNSExternal ophthalmoplegia ( motility impaired)1-Complete palsy: Limitation of ocular movement in all fields of gaze except temporally2-Incomplete palsy:partial limitation of ocular movement 3-Superior division palsy: Ptosis and inability to look up 4-Inferior division palsy: Inability to look nasally or inferiorly: pupil is involvedOCULOMOTOR (