#52. Eye motility disorders - general data. Amblyopia - types and treatment. Concomitant squint.

Question 1

What are Eye Motility Disorders CLASSIFIED INTO?

Answer 1

A) Neurogenic
B) Myogenic
c) Mechanical Causes

Question 2

What are NEUROGENIC Eye Motility Disturbances?

Answer 2

• LESIONS on the NERVES Supplying the Ocular Muscles
• MOST COMMON CAUSE for STRABISMUS
• Nerves AFFECTED:
  a. Oculomotor Nerve = Paralysis of Several Muscles

b. Trochlear Nerve = Paralysis of SUPERIOR OBLIQUE

c. Abducent Nerve = Paralysis of LACTERAL RECTUS

Question 3

What are MYOGENIC Eye Motility Disturbances?

Answer 3

• Grave’s Disease = ALTERED Contractility of Ocular Muscles
• Ocular Myasthenia Gravis

Question 4

What are the 2 EYE MOTILITY DISORDERS?

Answer 4

1) HETEROPHORIA

2) ORTHOPHORIA

Question 5

What is HETEROPHORIA?

Answer 5

• Is MUSCULAR IMBALANCE BTW the 2 Eyes
• Leading to MISALIGNMENT of VISUAL EXES under certain conditions

Question 6

What are the CAUSES of HETEROPHORIA?

Answer 6

• IMPAIRED Image Fusion
• DUE to:
  a. Alcohol Consumption
  b. Stress
  c. Fatigue
  d. Concussion
  e. Emotional Distress

Question 7

What are the SYMPTOMS of HETEROPHORIA?

Answer 7

• Headache
• Blurred Vision
• Diplopia
• Easily Fatigued Eyes

Question 8

What is the DIAGNOSIS of HETEROPHORIA?

Answer 8

• By the UNCOVER Test, where it STIMULATES the special conditions which Heterophoria manifests
• Focuses on the RESPONSE of the PREVIOUSLY COVERED eye, IMMEDIATELY AFTER being uncovered
• As ONCE UNCOVERED, the eye makes a VISIBLE ADJUSTMENT to ALLOW Fusion + RECOVER Binocular Vision

Question 9

What is the TREATMENT for HETEROPHORIA?

Answer 9

• Treatment ONLY for SYMPTOMATIC!
• Orthoptic Exercises
• STRABISMUS Surgery IF Heterophoria DETERIORATES INTO Strabismus

Question 10

What is ORTHOPHORIA?

Answer 10

Is MUSCULAR Balance BTW the 2 Eyes, affecting ONE or MORE Ocular Muscles at the SAME TIME!

• Leading to PARALLEL VISUAL EXES
• Resulting in GAZE PALSY or STRABISMUS

Question 11

What are the 2 FORMS of ORTHOPHORIA?

Answer 11

1) GAZE PALSY:
- IMPAIRMENT of Coordinated Eye movement

• Upward / Downward Gaze movements are IMPAIRED / ABSENT

2) PARALYTIC STRABISMUS:
- ISOLATED LIMITED motility in 1 eye
- ASYMMETRICAL LIMITED motility in both eyes

Question 12

What are the CAUSES of ORTHOPHORIA?

Answer 12

1) CONGENITAL
- PRENATAL Encephalitis
- APLASIA of Ocular Muscles
- Birth TRAUMA

2) ACQUIRED
- Diabetes Mellitus
- Multiple Sclerosis
- INTRACRANIAL Tumours
- Arteriosclerosis
- Central Ischaemia
- AIDS
- Trauma

Question 13

What are the SYMPTOMS of ORTHOPHORIA?

Answer 13

• Strabismus
• Gaze Palsy
• Double Vision

Question 14

What is the DIAGNOSIS for ORTHOPHORIA?

Answer 14

• EXAMINATION of the 9 DIAGNOSTIC POSITION of GAZE
• BIELSCHOWSKY HEAD TILT Test = Where TROCHLEAR Nerve Palsy is suspected
• MEASURE the ANGLE OF DEVIATION, using the HARMS TANGENT TABLE

Question 15

What is the TREATMENT for ORTHOPHORIA?

Answer 15

• SURGERY = PARALYTIC Strabismus MUST BE POSTPONED by a YEAR to ALLOW POSSIBLE Spontaneous Remission!
• PATCHING the Eye = SEVERE Diplopia
• EYEGLASS Lens w/ Prism Correction for PARALYSED eye

Question 16

What is CONCOMITANT SQUINT?

Answer 16

• Ocular DEVIATION that
• Measures the SAME in ALL directions of GAZE

Question 17

What are the CAUSES of CONCOMITANT SQUINT?

Answer 17

1) GENETICS = 60% have Family History

2) UNCORRECTED Refractive Errors
- Children with Hyperopia (Far Sightedness) HAVE ESOTROPIA as Convergence + Accommodation go hand-in-hand

3) INSUFFICIENT Fusion
- ANISOMETROPIA (Unequal Refractive Power in 2 eyes)
- ANISEIKONIA (Unequal Retinal Image Size)

4) UNILATERAL Visual IMPAIRMENT
- Severe near-sightedness
- corneal scarring
- lens opacities (cataract)
- macular changes

Question 18

What are the 4 TYPES of CONCOMITANT SQUINT?

Answer 18

1) ESOTROPIA = INWARD Deviation of Visual Axis

2) EXOTROPIA = OUTWARD Deviation of Visual Axis

3) HYPER / HYPO - TROPIA = Ocular Deviation with 1 eye HIGHER / LOWER than other

4) CYCLOTROPIA = ROTATION of 1 eye around its Visual Axis

Question 19

What is the DIAGNOSIS of CONCOMITANT SQUINT?

Answer 19

• Use the TELLER ACUITY CARD (Children)
• Unilateral Cover Test
• Maddox’s Cross = TO MEASURE ANGLE of Deviation
• Ophthalmoscope = DETERMINE the TYPE of Fixation (Centric / Eccentric)
• BAGOLINI TEST / LANG TEST = TEST Binocular Vision

Question 20

What is the TREATMENT for CONCOMITANT SQUINT?

Answer 20

• Eyeglasses
• Occlusion therapy
• Surgery