eye movements
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Questions and Answers

What is the primary treatment for Ocular Myositis?

  • Prisms
  • Surgery
  • Corticosteroids (correct)
  • Botox

    • The ______ barked

    dog

    What is the main cause of Dissociated Vertical Deviation?

  • Reduced light entering the eye (correct)
  • Facial asymmetry
  • Inferior oblique weakening
  • Superior rectus recession

    • Pseudostrabismus is a condition where there is a manifest deviation of the visual axes.

    <p>False</p> Signup and view all the answers

    What is the purpose of investigating binocular single vision and fusional control in the management of Pseudostrabismus?

    <p>To determine if further treatment is needed if associated with true strabismus</p> Signup and view all the answers

    The _______________ muscle is responsible for torsion.

    <p>Oblique</p> Signup and view all the answers

    What is a common sign of torsion?

    <p>Disc appears displaced and intorted or extorted in relation to the fovea</p> Signup and view all the answers

    Match the following terms with their definitions:

    <p>Pseudostrabismus = Appearance of strabismus when no manifest deviation of the visual axes is present Dissociated Vertical Deviation = Spontaneous elevation of either eye intermittently when the stimulus to fixate is reduced Torsion = Rotation of the eye around its anteroposterior axis</p> Signup and view all the answers

    Anterior transposition of IO is a surgical procedure used to treat Dissociated Vertical Deviation.

    <p>True</p> Signup and view all the answers

    What is the primary concern when diagnosing muscle inflammation/swelling on a CT scan?

    <p>Rhabdomyosarcoma</p> Signup and view all the answers

    True or False: A disorder of supranuclear pathways can result in diplopia.

    <p>False</p> Signup and view all the answers

    What is the purpose of the horizontal gaze centre in the midbrain?

    <p>The horizontal gaze centre controls horizontal movement to the same side and projects to the ipsilateral abducens nucleus and to the medial rectus sub nucleus of the third nerve on the opposite side via MLF.</p> Signup and view all the answers

    The _______________________ pathway lies at the region of the thalamus and midbrain.

    <p>vertical</p> Signup and view all the answers

    Match the following brain areas with their functions in eye movement control:

    <p>Frontal pre-motor area = Initiates saccades Occipito-parietal area = Initiates pursuits Vestibular nuclei in the pons = Initiates VOR</p> Signup and view all the answers

    What is the typical latency or delay of the ocular motor system's response to a saccadic eye movement?

    <p>100-300ms</p> Signup and view all the answers

    True or False: The basal ganglia and thalamus are involved in smooth pursuit control.

    <p>True</p> Signup and view all the answers

    What is the typical presentation of Double Elevation Palsy?

    <p>Limited elevation of one eye in both adduction and abduction, often with a congenital origin.</p> Signup and view all the answers

    The _______________________ test may show full passive movement (negative result) or it may be positive in Double Elevation Palsy.

    <p>Forced duction</p> Signup and view all the answers

    What is the primary concern when diagnosing muscle inflammation/swelling on a CT scan?

    <p>Rhabdomyosarcoma</p> Signup and view all the answers

    A disorder of supranuclear pathways can result in diplopia.

    <p>False</p> Signup and view all the answers

    What is the function of the middle temporal visual area in the superior temporal sulcus?

    <p>Encoding speed and direction of moving stimuli</p> Signup and view all the answers

    The horizontal gaze centre projects to the ipsilateral abducens nucleus and to the _______________ sub nucleus of third nerve on opposite side via MLF.

    <p>medial rectus</p> Signup and view all the answers

    What is the typical presentation of Double Elevation Palsy?

    <p>Limited elevation of one eye in both adduction and abduction</p> Signup and view all the answers

    Match the following brain areas with their functions in eye movement control:

    <p>Frontal eye fields = Aid programming of predictive pursuit movements, initiation and maintenance Occipital cortex = Visual information processing Thalamus = Aid smooth pursuit control Parietal cortex = Motion processing</p> Signup and view all the answers

    The basal ganglia and thalamus are involved in saccade control.

    <p>False</p> Signup and view all the answers

    What is the typical latency or delay of the ocular motor system's response to a saccadic eye movement?

    <p>100-300ms</p> Signup and view all the answers

    The vertical pathway lies at the region of the _______________ and midbrain.

    <p>thalamus</p> Signup and view all the answers

    What is the function of the superior temporal sulcus in smooth pursuit eye movement?

    <p>Encoding speed and direction of moving stimuli</p> Signup and view all the answers

    What is the primary goal of surgery in Dissociated Vertical Deviation?

    <p>To reduce frequent spontaneous elevation of one or both eyes</p> Signup and view all the answers

    True or False: Ptosis can give the appearance of a horizontal deviation.

    <p>False</p> Signup and view all the answers

    What is the purpose of investigating binocular single vision and fusional control in the management of Pseudostrabismus?

    <p>To determine if further treatment is needed as indicated</p> Signup and view all the answers

    The _______________ muscle is responsible for torsion.

    <p>Oblique</p> Signup and view all the answers

    What is a common sign of torsion?

    <p>Intorted or extorted disc</p> Signup and view all the answers

    Match the following terms with their definitions:

    <p>Pseudostrabismus = Appearance of strabismus when no manifest deviation of the visual axes is present Dissociated Vertical Deviation = Spontaneous elevation of either eye intermittently when the stimulus to fixate is reduced Torsion = Rotation of the eye around its anteroposterior axis</p> Signup and view all the answers

    The fovea-optic disc relationship is observed in congenital cases to measure torsion _______.

    <p>objectively</p> Signup and view all the answers

    True or False: A wide IPD gives the appearance of a convergent deviation.

    <p>False</p> Signup and view all the answers

    What is the characteristic feature of CPEO Myositis?

    <p>Bilateral ptosis and orbicularis weakness</p> Signup and view all the answers

    Kearns Sayre syndrome is associated with CPEO Myositis.

    <p>True</p> Signup and view all the answers

    What is the typical age of onset for CPEO Myositis in Kearns Sayre syndrome?

    <p>before the age of 20 years</p> Signup and view all the answers

    CPEO Myositis is a type of mitochondrial disorder associated with ____________.

    <p>Kearns Sayre syndrome</p> Signup and view all the answers

    What is the primary investigation for Ocular Myositis?

    <p>Case history</p> Signup and view all the answers

    Ocular Myositis is a chronic condition that requires lifelong treatment.

    <p>False</p> Signup and view all the answers

    Match the following clinical features with the correct condition:

    <p>Painful diplopia = Ocular Myositis Bilateral ptosis = CPEO Myositis Proptosis = Ocular Myositis Normal pupils = CPEO Myositis</p> Signup and view all the answers

    What is the primary management strategy for Ocular Myositis?

    <p>Corticosteroids</p> Signup and view all the answers

    Study Notes

    CPEO Myositis

    • Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial disorder associated with Kearns-Sayre Syndrome
    • Clinical features:
      • Progressive symmetrical loss of motility, with upgaze being the first to be affected
      • Bilateral ptosis and orbicularis weakness
      • Normal pupils and accommodation
      • Diplopia is not usually complained of due to symmetrical and slow progression
      • Final stages have virtually no eye movements with a positive forced duction test (FDT) due to secondary fibrosis
    • Limitation of eye movement
    • Kearns-Sayre Syndrome:
      • CPEO in childhood (before the age of 20 years)
      • Fine pigmentary retinopathy
      • Clinical features: heart conduction block, deafness, cerebellar ataxia
    • Management:
      • Funduscopy
      • ECG
      • Orthoptic assessment (including UFOF, ptosis preps/Fresnel's)

    Ocular Myositis

    • Inflammation of one or more extraocular muscles (EOMs) resulting in impairment of function
    • Sudden onset, can be acute or chronic (acute onset can become chronic)
    • Clinical features:
      • Painful diplopia
      • Acute pain (periocular pain)
      • Proptosis
      • Oedema (periorbital/chemosis/swelling of the conjunctiva/eyelid swelling and redness)
      • Underlying inflammatory disease/autoimmune disorder
      • Restricted ocular motility and strabismus
    • Investigations:
      • Case history (painful diplopia and photophobia)
      • Visual acuity (reduced)
      • Cover test (type of strabismus relates to the affected EOM)
      • Ocular motility (exophthalmos and lid oedema is evident in multiple EOM paresis)
    • Diagnosis and management:
      • Corticosteroids (highly effective in medical management of inflammation)
      • Surgery may be required for residual restrictive strabismus
      • Prisms may be required
      • Consider Botox
      • Self-limiting, usually resolves within 8 weeks
      • CT scan shows marked inflammation/swelling of one or more muscles, including the tendon
      • Ensure it is not Rhabdomyosarcoma, a highly malignant tumor that presents in childhood, usually associated with acute proptosis and strabismus

    Supra/Infra/Inter Pathways

    Supranuclear Disorders

    • Signals controlling ocular movement are initiated in the cerebral hemispheres and then transmitted to the gaze centres in the midbrain and oculomotor nuclei
    • Supra-nuclear neuronal pathways conduct impulses from cerebral hemispheres to gaze centres
    • Control saccades, pursuits, and vestibular
    • Disorder results in palsies of conjugate (connected) movement

    Gaze Palsies

    • Inability to make conjugate eye movements in one direction
    • Does not cause diplopia as visual axis usually remains parallel
    • Investigating each reflex and conjugate movement makes it possible to establish where the lesion lies
    • E.g. frontal lesion = unilateral saccadic palsies, occipital lesion = unilateral pursuit palsies

    Other

    • Double elevation palsy: often congenital, presumed to be caused by a supranuclear defect
    • Dissociated vertical deviation: spontaneous elevation of either eye intermittently when the stimulus to fixate is reduced
    • Pseudostrabismus: appearance of strabismus when no manifest deviation of the visual axes is present
    • Torsion: oblique muscle is responsible, can be measured objectively or subjectively

    CPEO Myositis

    • Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial disorder associated with Kearns-Sayre Syndrome
    • Clinical features:
      • Progressive symmetrical loss of motility, with upgaze being the first to be affected
      • Bilateral ptosis and orbicularis weakness
      • Normal pupils and accommodation
      • Diplopia is not usually complained of due to symmetrical and slow progression
      • Final stages have virtually no eye movements with a positive forced duction test (FDT) due to secondary fibrosis
    • Limitation of eye movement
    • Kearns-Sayre Syndrome:
      • CPEO in childhood (before the age of 20 years)
      • Fine pigmentary retinopathy
      • Clinical features: heart conduction block, deafness, cerebellar ataxia
    • Management:
      • Funduscopy
      • ECG
      • Orthoptic assessment (including UFOF, ptosis preps/Fresnel's)

    Ocular Myositis

    • Inflammation of one or more extraocular muscles (EOMs) resulting in impairment of function
    • Sudden onset, can be acute or chronic (acute onset can become chronic)
    • Clinical features:
      • Painful diplopia
      • Acute pain (periocular pain)
      • Proptosis
      • Oedema (periorbital/chemosis/swelling of the conjunctiva/eyelid swelling and redness)
      • Underlying inflammatory disease/autoimmune disorder
      • Restricted ocular motility and strabismus
    • Investigations:
      • Case history (painful diplopia and photophobia)
      • Visual acuity (reduced)
      • Cover test (type of strabismus relates to the affected EOM)
      • Ocular motility (exophthalmos and lid oedema is evident in multiple EOM paresis)
    • Diagnosis and management:
      • Corticosteroids (highly effective in medical management of inflammation)
      • Surgery may be required for residual restrictive strabismus
      • Prisms may be required
      • Consider Botox
      • Self-limiting, usually resolves within 8 weeks
      • CT scan shows marked inflammation/swelling of one or more muscles, including the tendon
      • Ensure it is not Rhabdomyosarcoma, a highly malignant tumor that presents in childhood, usually associated with acute proptosis and strabismus

    Supra/Infra/Inter Pathways

    Supranuclear Disorders

    • Signals controlling ocular movement are initiated in the cerebral hemispheres and then transmitted to the gaze centres in the midbrain and oculomotor nuclei
    • Supra-nuclear neuronal pathways conduct impulses from cerebral hemispheres to gaze centres
    • Control saccades, pursuits, and vestibular
    • Disorder results in palsies of conjugate (connected) movement

    Gaze Palsies

    • Inability to make conjugate eye movements in one direction
    • Does not cause diplopia as visual axis usually remains parallel
    • Investigating each reflex and conjugate movement makes it possible to establish where the lesion lies
    • E.g. frontal lesion = unilateral saccadic palsies, occipital lesion = unilateral pursuit palsies

    Other

    • Double elevation palsy: often congenital, presumed to be caused by a supranuclear defect
    • Dissociated vertical deviation: spontaneous elevation of either eye intermittently when the stimulus to fixate is reduced
    • Pseudostrabismus: appearance of strabismus when no manifest deviation of the visual axes is present
    • Torsion: oblique muscle is responsible, can be measured objectively or subjectively

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    Description

    Learn about Chronic Progressive External Ophthalmoplegia, a mitochondrial disorder associated with Kearns-Sayre Syndrome. Understand its clinical features, including progressive symmetrical loss of motility, bilateral ptosis, and more.

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