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MUSCULOFACIAL ANOMALIES Moderator- Dr. (Prof) M. I. MAGDUM Presenter- Dr. Devanshu Arora February 18, 2015 Department of Ophthalmology, JNMC, Belagavi 1

Musculofacial anomalies & Ocular Myopathies

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MUSCULOFACIAL ANOMALIESModerator- Dr. (Prof) M. I. MAGDUM

Presenter- Dr. Devanshu Arora

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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INTRODUCTION• MUSCULOFACIAL ANOMALIES refers to a group of

congenital disorders in which there are errors in the innervation of Ocular & Facial muscles.

• These conditions are now referred to as-CONGENITAL CRANIAL DYSINNERVATION DISORDERS

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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OVERVIEW1. Relevant Anatomy & Physiology2. Musculofacial Anomalies (congenital cranial

dysinnervation disorders):• Duane Retraction Syndrome• Brown Syndrome• Congenital Fibrosis of Extraocular Muscles• Mobius Syndrome• Marcus Gunn Jaw-winking Syndrome

3. Ocular Myopathies:• Myasthenia Gravis• Myotonic Dystrophy• Chronic Progressive External Ophthalmoplegia• Lambert-Eaton Myasthenic Syndrome

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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ANATOMY OF EXTRAOCULAR MUSCLES• Visual axis (line of vision) is the line passing from the fovea,

through the nodal point of the eye, which is located at the posterior capsule of the lens, to the point of fixation (object of regard).

• Anatomical axis (Optic Axis) is a line passing from the posterior pole through the centre of the cornea.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

• Primary Position of Gaze: When the eye is looking straight ahead at a fixed point on the horizon with the head erect. In this position the visual axis forms an angle of 23° with the orbital axis

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MUSCLE ORIGIN INSERTION INNERVATION

MEDIAL RECTUS Annulus of Zinn 5.5 mm behind medial limbus Cranial Nerve III

LATERAL RECTUS Annulus of Zinn 6.9 mm behind lateral limbus Cranial Nerve VI

SUPERIOR RECTUS Annulus of Zinn 7.7 mm behind superior limbus Cranial Nerve III

INFERIOR RECTUS Annulus of Zinn 6.5mm behind inferior limbus Cranial Nerve III

SUPERIOR OBLIQUE Orbital apex above the Annulus of Zinn

Posterior Upper temporal quadrant of

GlobeCranial Nerve IV

INFERIOR OBLIQUEAnteriorly from orbital wall lateral to lacrimal

fossa

Posterior Lower temporal quadrant of

GlobeCranial Nerve III

LEVATOR PALPEBRAE

SUPERIORIS (LPS)

Orbital apex above the Annulus of Zinn

Skin of the upper eyelid & superior

tarsal PlateCranial Nerve III

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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MUSCLE PRIMARY ACTION SUBSIDIARY ACTION

Medial Rectus Adduction --

Lateral Rectus Abduction --

Superior Rectus Elevation (best when eye is in abducted position) Intorsion & Adduction

Inferior Rectus Depression (best when eye is in abducted position) Extorsion & Adduction

Superior Oblique IntorsionDepression (best when eye

is in adducted position)& Abduction

Inferior Oblique ExtorsionElevation (best when eye is

in adducted position)& Abduction

ACTIONS OF EXTRAOCULAR MUSCLES

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• Agonist–antagonist pairs are muscles of the same eye that move the eye in opposite directions. The agonist is the primary muscle moving the eye in a given direction. The antagonist acts in the opposite direction to the agonist.

• Sherrington law of reciprocal innervation states that increased innervation to an extraocular muscle is accompanied by a reciprocal decrease in innervation to its antagonist.

For example- As the right eye abducts, the Right Lateral Rectus muscle receives innervation & contracts while the Right Medial Rectus receives decreased innervation & automatically relaxes.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

EXTRAOCULAR MUSCLE PHYSIOLOGY

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• Yoke Muscles: 2 Muscles (1 in each eye) that are the prime movers of their respective eyes in a given position of gaze

For Example- when the eyes move into right gaze (dextroversion), the right lateral rectus muscle & the left medial rectus muscle are yoke muscles.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Hering Law of Equal Innervation states that during any conjugate eye movement, equal and simultaneous innervation flows to the yoke muscles concerned with the desired direction of gaze.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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CONGENITAL CRANIAL DYSINNERVATION

DISORDERSA number of well defined syndromes characterized by

congenital limitation of eye movements were found to be resulting from aberrant innervation of the ocular & facial

musculature.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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DUANE RETRACTION SYNDROME (DRS)

• Duane’s Syndrome also known as Stilling-Turk syndrome

• Congenital non progressive ocular motility defect

• There are Type I,II & III – the common characteristic feature being retraction of the globe on adduction or attempted adduction.

• There is limitation or total absence of abduction & partial restriction of adduction may also be present

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Most cases are sporadic but 5%-10% show Autosomal Dominant Inheritance

• There is failure of innervation of the Lateral Rectus by the 6th nerve, with anomalous innervation of the lateral rectus by fibers from the 3rd nerve

• Anatomical and imaging studies have shown that in most cases there is aplasia of the sixth cranial nerve nucleus, and an aberrant branch of oculomotor nerve has innervated the lateral rectus.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

PATHOGENESIS of Duane’s Syndrome

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• So on attempted adduction because of innervation by the oculomotor nerve there is co-contraction of the medial & lateral recti (referred to as synkinesis phenomenon) which results in retraction of the globe.

• Additionally, an association of DRS is seen with Marcus Gunn jaw-winking, also a synkinesis phenomena (which occurs due to aberrant trigeminal nerve innervation of levator palpebrae superioris)

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Usually Unilateral• About 15% case are Bilateral (in which also one side

involvement is usually subtle)• In Primary Position the eyes look straight or there may be

slight Eso or Exotropia depending on the type, but Binocular Single Vision is usually maintained.

• A Face turn is often noted which the patient uses for their lateral rectus weakness to allow them to use both eyes together

• Restricted Abduction (complete or partial)• Restricted Adduction (usually partial)• Retraction of the Globe on adduction

Narrowing of palpebral fissure

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

CLINICAL FEATURES of Duane’s Syndrome

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• An up-shoot or down-shoot in adduction may be present.

• It has been suggested that this is a ‘Leash’ phenomenon, that because of co-contraction of medial & lateral rectus, the tight lateral rectus muscle slips over or under the globe and produces an anomalous vertical movement of the eye.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Type I , the most common, is characterized by: Marked restriction or total absence of abduction Normal or mildly limited adduction In the primary position, straight or slight esotropia

• Type II, the least common, is characterized by: Limitation of adduction Normal or mildly limited abduction In primary position, straight or slight exotropia

• Type III, is characterized by: Limited adduction and abduction. In the primary position, straight, slight esotropia or

slight exotropia

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

TYPES OF DRS: HUBER CLASSIFICATION

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• Associated Ocular Anomalies-Pupillary abnormalities (anisocoria), Cataract,

Choroidal colobomas

• Non Ocular Anomalies-Perceptive Deafness with associated speech

disordersCervical spina bifidaGoldenhar’s Syndrome (hemifacial microsomia,

ocular dermoids, ear anomalies, preauricular skin tags & upper eyelid colobomas)

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

ASSOCIATIONS OF DRS

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• Most patients do not need surgical intervention

• Surgery is reserved for cases with primary position deviations & marked globe retraction or for cosmetic reasons- abnormal head posture

• For DRS with esotropia- Recession of Medial Rectus on the involved side has been the most often used procedure

• For DRS with exotropia- Recession of Lateral Rectus on the involved side.

• Patients with type III DRS, having severe globe retraction may be helped by recession of both medial & lateral rectus muscles which may also help in reducing the vertical excursions.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

MANAGEMENT of Duane’s

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BROWN SYNDROME• Described by Harold W. Brown in 1950 as the Superior

Oblique Sheath Syndrome

• Characteristic restriction of elevation in adduction that improves in abduction

• Caused by restriction of superior oblique tendon at the trochlear pulley.

• Usually congenital but occasionally acquired

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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ETIOLOGY of Brown’s Syndrome :1. Congenital

• Idiopathic.• ‘Congenital click syndrome’ where there isimpaired movement of the superior oblique tendonthrough the trochlea.

2. Acquired• Trauma to the trochlea or superior obliquetendon.• Inflammation of the tendon, which may be causedby Systemic Inflammatory Diseases (Rheumatoid arthritis), pan sinusitis or scleritis.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Usually sporadic, some cases show Autosomal Dominant Inheritance

• In mild forms, eyes are usually straight in primary position & there is no hypotropia

• Sever forms show a primary gaze hypotropia, usually accompanied by a chin-up head posture.

• Limited elevation in adduction• Limited elevation on upgaze is common• Normal elevation in abduction• Down shoot in adduction may be seen• Positive forced duction test on elevating the globe in

adduction is a major sign essential for the Diagnosis

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

CLINICAL FEATURES of Brown Syndrome

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• How to differentiate Brown Syndrome from Inferior Oblique Muscle Palsy?

Forced duction test is negative (no resistance to elevation in adduction) in Inferior Oblique Palsy

No depression on adduction

• Orbital Floor fracture:Restriction of elevation not only in adduction, but also

in direct elevation in primary gaze

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Observation alone remains the most common form of management

• Treatment of the underlying cause is indicated in acquired cases.

• Systemic treatment should be started in rheumatoid arthritis or other systemic inflammatory diseases & resolution is observed. Corticosteroids injections can also be injected near the trochlea.

• Surgery is indicated in sever cases (having hypotropia & AHP):

Superior Oblique Tenontomy is now the procedure of choice

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

MANAGEMENT of Brown Syndrome

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CONGENITAL FIBROSIS OF EXTRAOCULAR MUSCLES (CFEOM)

• Congenital fibrosis Syndrome, is a group of congenital disorders characterized by restriction of the extraocular muscles and replacement of the muscles by fibrous tissue.

• It can be unilateral or bilateral, with the bilateral form being more common

• The spectrum ranges from isolated fibrosis of a single muscle to B/L involvement of all EOMs

• Familial disorder showing AutosomalDominant Inheritance

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Congenital fibrosis syndrome has traditionally been considered a primary muscle disorder

• Recently, CFEOM has been accepted to be of neurogenic origin similar to that of DRS but involving the III cranial nerve complex.

• Co-contraction phenomenon resulting in globe retraction has also been described in patients with CFEOM

• But the exact mechanism & cause is unknown

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Congenital non-progressive bilateral external ophthalmoplegia

• Congenital non-progressive bilateral ptosis• In the primary position each eye is fixed below the

horizontal by about 10°.• The hypotropic eye may be secondarily exotropic,

esotropic or neutral.• The degree of residual horizontal movement varies from

full to absent.• Vertical movements are always severely restricted with

inability to elevate the eyes above the horizontal plane.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

CLINICAL FEATURES of CFEOM

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• A subset of cases show unilateral fibrosis with enophthalmos and ptosis

• These are non familial

• Systemic associations- Mental retardation Facial palsy Dental anomalies Spina bifida Prader-willi syndrome

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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MANAGEMENT of CFEOM :• Surgery is difficult and requires release of the restricted

muscles (weakening procedures)

• Fibrosis of adjacent tissue may be present as well.

• A good surgical result aligns the eyes in primary position, but full ocular movements cannot be restored

• Outcome of such surgeries is always unpredictable

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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MÖBIUS SYNDROME• Heterogeneous clinical disorder, which includes

congenital facial palsy with impairment of ocular abduction due to sixth nerve palsy

• Developmental disorder of the brainstem rather than an isolated cranial nerve disorder

• The ocular motility disturbances in Mobius syndrome are frequently bizarre and asymmetrical, resembling more of a congenital fibrosis pattern than cranial nerve palsies

• Most cases are sporadic

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Neural Imaging studies have shown:Brain stem hypoplasia in the region of the sixth and

the seventh nerve & hypoplasia of extraocular muscles and intraorbital motor nerves

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Systemic features : Bilateral facial palsy which is usually asymmetrical

giving rise to a mask-like facial expression and problems with lid closure

Paresis of the 12th cranial nerves which results in atrophy of the tongue

Mild mental handicap Limb & Chest wall anomalies

• Ocular features : Horizontal gaze palsy is present in 50% of cases. Bilateral 6th nerve palsy Occasionally 3rd and 4th nerve palsy and ptosis

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

CLINICAL FEATURES of Mobius Syndrome

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• Non surgical management-Detection & treatment of amblyopia, corneal

exposure & refractive errors

• Surgical management- No single surgery usefulMedial rectus muscle recession is triedTransposition of vertical recti to insertion of Lateral Rectus described

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

MANAGEMENT of Mobius Syndrome

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STRABISMUS FIXUS• It is a rare congenital anomaly in which both eyes are

fixed in either the convergent position caused by fibrous tightening of the Medial Recti

(Convergent Strabismus Fixus)

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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OR• fibrosis of both Lateral Recti (Divergent Strabismus Fixus)

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• No horizontal movement is possible• Diplopia does not occur because of suppression of image

from one eye• Amblyopia also does not develop because the patient

tends to use both eyes alternately.

TREATMENT OF STRABISMUS FIXUS-• Involves recession of medial recti along with recession of

conjunctiva & tenon’s capsule but abduction beyond midline can never be achieved

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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MARCUS GUNN JAW-WINKING SYNDROME

• Characterized by a congenital ptosis that includes an associated winking motion of the affected eyelid on the movement of the jaw

• Usually unilateral & is a form of synkinetic ptosis.

• An aberrant connection appears to exist between the motor branches of the trigeminal nerve (CN V3) innervating the external pterygoid muscle and the fibers of the superior division of the oculomotor nerve (CN III) that innervate the levator superioris muscle of the upper eyelid

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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Signs and Symptoms of Marcus Gunn jaw-winking syndrome:• Mild-to-moderate blepharoptosis, usually unilateral• Synkinetic upper eyelid movement with jaw-winking after one

of the following: Mouth opening Jaw movement toward the contralateral side Chewing Sucking Jaw protrusion Clenching teeth together Swallowing

• Usually, parents first notice the phenomenon while the baby is bottle-feeding or breastfeeding.

• Strabismus- Vertical deviations, usually a hypotropia on the involved side

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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OCULAR MYOPATHIES

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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MYASTHENIA GRAVIS• Is a Neuromuscular disorder characterized by weakness

& fatigability of skeletal muscles

• It is an autoimmune disease in which antibodies mediate damage & destruction of acetyl choline receptors at neuromuscular junction.

• Thus there is decrease in the number of available AchRs at the neuromuscular junction although Ach is released normally; leading to failure of generation of Action potential in the muscle fibers.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• The amount of ACh released per impulse also declines on repeated activity (called presynaptic rundown) resulting in activation of fewer and fewer muscle fibers by successive nerve impulse responsible for FATIGUE

• How the autoimmune response in Myasthenia is initiated is not completely understood. However, the thymus appears to play a role.

• Thymic tumors are seen in about 10% patients.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Affects individuals in all age groups• More common in women specially in their twenties &

thirties• Affects men in their fifties & sixties

• The cardinal features are weakness and painless fatigability of muscles. The weakness increases on repeated use of the muscle (or exercise) and improves following rest.

• Therefore symptoms are worse toward the end of the day & less in the morning after sleep.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

CLINICAL FEATURES OF MYASTHENIA GRAVIS

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• The distribution of muscle weakness often has a characteristic pattern, the lid & extraocular muscles being involved early in the course followed by facial weakness & muscles involved in mastication and speech.

• Most frequent presentation is with Ptosis & Diplopia

• In 85% of patients weakness becomes generalized, affecting the limb muscles as well.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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SIGNS:a. Peripheral-

• Weakness, particularly of the arms and proximal muscles of the legs.

• Permanent myopathic wasting may occur in long-standing cases.

b. Facial-• Lack of expression and Ptosis (myopathic facies)

c. Bulbar-• Dysphagia• Dysarthria and• Difficulty in chewing

d. Respiratory- rarely respiratory crisis may occur

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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OCULAR FEATURES:90% patients have both ptosis & weak extraocular movements

a. Ptosis-• Bilateral and frequently asymmetrical• Increases on prolonged upgaze (>30secs)• Cogan Twitch Sign is a brief upshoot of eyelid when the

patient looks straight ahead after looking down for several minutes

• Positive Ice Test: An Ice pack is placed on the eyelid for 2 minutes which results in an improvement in the severity of ptosis

(Cold improves neuromuscular transmission)

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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b. Diplopia-• Is frequently vertical, although any or all of the

extraocular muscles may be affected

• When myasthenia is limited to ocular muscles and no generalized involvement is present, it is known as Ocular Myasthenia

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Serum anti-AChR antibodies levelsThe presence of anti-AChR antibodies is diagnostic of Myasthenia, but a negative test does not exclude the disease.

• Thoracic CT or MRIto detect thymoma

• Single-fiber Electromyography (SFEMG) is the latest diagnostic test & the most sensitive investigation.

• Edrophonium Test or the Tensilon Test

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

INVESTIGATIONS for Myasthenia Gravis

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EDROPHONIUM TEST:a. Objective baseline measurements are made of the

ptosis, or of the diplopia with a Hess testb. Intravenous injection of atropine 0.3 mg is given to

minimize muscarinic side-effectsc. Intravenous test dose of 0.2 mL (2 mg) edrophonium

hydrochloride is given. If definite symptomatic improvement is noted, the test is terminated forthwith

d. The remaining 0.8 mL (8 mg) is given after 60 seconds, provided there is no hypersensitivity

e. Final measurements/repeat Hess testing are made and the results compared

But Edrophonium being ultra short acting, its result lasts only for 5 mins during which the measurements are made

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• Anticholinesterase Medications:Pyridostigmine most commonly usedStarted at a dose of 30-60mg 3-4 times a dayIncreased or decreased as per patient’s response

• Thymectomy:To remove a thymoma if presentAlso tried as a treatment in generalized MG

• Immunosuppression:Steroids or AzathioprineFor refractory cases high dose Cyclophosphamide

• Plasmapheresis &• Intravenous Immunoglobulin

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

TREATMENT of Myasthenia Gravis

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MYOTONIC DYSTROPHY• Myotonia means delayed muscular relaxation after

cessation of voluntary effort which is the characteristic feature of the disease.

• Shows Autosomal Dominant Inheritance

• Presentation is in the 3rd–6th decades with weakness of the hands and difficulty in walking.

• Successive generations exhibit progressively earlier onset and greater severity of disease

(Anticipation)

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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Signs-• Peripheral- Difficulty in releasing grip, muscle wasting and

weakness.

• Central- Mournful facial expression caused by bilateral facial wasting with hollow cheeks, and slurred speech from involvement of the tongue and pharyngeal muscles.

• Other- Frontal baldness in males, hypogonadism, mild endocrine abnormalities, cardiomyopathy, pulmonary disease, intellectual deterioration and bone changes

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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Ocular Features-

• Early Onset Cataract- “Christmas Tree Cataract”

• Ptosis

• Others-External Ophthalmoplegia, pupillary light-near dissociation, mild pigmentary retinopathy, bilateral optic atrophy and low intraocular pressure

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

(because of its resemblance to the coloured lights on a Christmas tree)

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Myotonic Facies

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CHRONIC PROGRESSIVE EXTERNAL OPHTHALMOPLEGIA

• Chronic progressive external ophthalmoplegia (CPEO) is a disorder characterized by slowly progressive paralysis of the extraocular muscles.

• Patients usually experience bilateral, symmetrical, progressive ptosis, followed by weakness of the extraocular muscles months to years later

• Ciliary and iris muscles are not involved

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• CPEO is the most frequent manifestation of mitochondrial myopathies

• It may occur in isolationor

• In association with certain syndromes like: Kearns–Sayre syndrome & Oculopharyngeal Dystrophy

• Mitochondrial DNA encodes for essential components of the respiratory chain. Deletions of various lengths of mtDNA results in defective mitochondrial function.

• Extraocular muscles are affected preferentially because their fraction of mitochondrial volume is several times greater than that of other skeletal muscle.

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Impaired protein synthesis in these mitochondria accounts for the histological hallmark- Ragged Red Fibers

• Muscle fibers stained with Gomori trichrome stain show an abnormal accumulation of enlarged mitochondria beneath the sarcolemma giving the unusual appearance

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• CPEO tends to begin in young adulthood• Ptosis usually is the first clinical sign, which is bilateral &

symmetrical• As the ptosis progresses, the patient may use the frontalis

muscle to elevate the eyelids and adopt a chin-up head position

• External ophthalmoplegia is also typically symmetrical• It is characterized by a progressive course without remission

or exacerbation.• Initially upgaze is involved subsequently lateral gaze is

affected• Because of symmetrical loss of eye movements there isno diplopia [differentiating feature from Myasthenia Gravis]

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

CLINICAL FEATURES of CPEO

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• Multiorgan System Disorder• Triad of Clinical findings:

1. Onset before the age of 20yr2. Chronic Progressive External Ophthalmoplegia3. Pigmentary Retinopathy

• Plus features like- Complete Heart Block & Cerebellar Ataxia

• Other features- Deafness, diabetes, short stature, renal disease and Dementia

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

Kearns–Sayre Syndrome

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Fundus typically shows a ‘salt and pepper’ appearance

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DIAGNOSTIC TESTS-

• Lumbar puncture shows elevation of CSF protein concentration (>1 g/l).

• ECG demonstrates cardiac conduction defects

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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• Autosomal Dominant Inheritance

• Weakness of pharyngeal Muscles: causing Dysphagia &• Wasting of temporalis

• Ophthalmic featuresBilateral Ptosis andProgressive External Ophthalmoplegia

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

Oculopharyngeal Dystrophy

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Lambert-Eaton Myasthenic Syndrome

• An autoimmune disorder of the neuromuscular junction often associated with underlying,Small Cell Bronchial Carcinoma

• Systemic features include gradual difficulty in walking that may precede clinical manifestation of the associated carcinoma by up to two years.

• Ophthalmic features are ptosis and diplopia

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

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CHRONIC PROGRESSIVE

EXTERNAL OPHTHALMOPLEGIA

MYASTHENIA GRAVIS

LAMBERT-EATON MYASTHENIC SYNDROME

FATIGUABILITY No Yes No

DIPLOPIA No Yes Yes

Other eye signs Pigmentary Retinopathy - -

RNS test - Decremental Response

Incremental Response

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

Differentiation of Conditions Producing Ptosis & Extraocular Muscles Weakness

Page 67: Musculofacial anomalies & Ocular Myopathies

67February 18, 2015 Department of Ophthalmology, JNMC, Belagavi

Page 68: Musculofacial anomalies & Ocular Myopathies

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REFERENCES• Clinical Ophthalmology–A Systematic Approach 7th edition

(by Jack J Kanski)

• Ophthalmology 4th edition- Yanoff & Duker

• Pediatric Ophthalmology & Strabismus (Section 6), American Academy of Ophthalmology(AAO)

• Manual Of Squint- Leela Ahuja

• Harrison's Principles of Internal Medicine Vol-II (17th Ed)

February 18, 2015 Department of Ophthalmology, JNMC, Belagavi