5.4 Ptosis

Examination Outline

Introductory Comments

In clinical examinations, a patient with (blepharo)ptosis may present in two different ways. Firstly, as a neuro-ophthalmic diagnostic dilemma (particularly neurogenic and myogenic ptosis); secondly, as an oculoplastic management dilemma (particularly aponeurotic and mechanical ptosis). The candidate must be aware of this and be able to simultaneously consider diagnosis and management options.

The ptosis examination is extremely important as some systemic conditions that present with ptosis are potentially life threatening. These include: Myasthenia Gravis, Chronic Progressive External Ophthalmoplegia (CPEO), Horner’s syndrome and pupil-involving CNIII palsy.

Examination Structure

1. Visual Acuity (Best Corrected)

Amblyopia may occur following congenital ptosis. A ptotic lid can induce astigmatism and reduce the BCVA.

2. General Inspection

  • Always shake the patient’s hand with a firm grip
    • A grip that is slow to release is suggestive of Myotonic Dystrophy
  • General appearance / speech (Myasthenia Gravis, Myotonic dystrophy, CPEO, CN III palsy)
    • Walking aids, slurred or nasal speech and mask-like facies may suggest a neuromuscular disorder
    • Patients may adopt a chin up posture or exhibit brow overaction to compensate for the ptosis
  • Upper eyelid / Ptosis (partial vs. complete ptosis; unilateral vs. bilateral ptosis)
    • Does it cross the visual axis (especially in a child)?
    • Chin-up head posture, brow over-action (compensatory)
    • Dermatochalasis, brow ptosis
    • Absent or high lid crease; Deep upper lid sulcus (aponeurotic ptosis).
  • Strabismus (CN III palsy, myogenic causes of ptosis)
  • Pupils (anisocoria) (Horner’s syndrome, CN III palsy)
    • If anisocoria is present, measure the pupil size in light and dark to confirm which pupil is abnormal. Anisocoria should direct you towards finding a potentially life-threatening neurological cause (Horner’s Syndrome or CN III palsy)
  • Heterochromia iridis (Congenital or early acquired Horner’s Syndrome)
  • Proptosis or enophthalmos (measure or request Hertel exophthalmometry)
  • Other features: reverse ptosis, anhidrosis
Differentiating an Aponeurotic Ptosis from a Congenital Ptosis

± Ask the patient to “Look down at my finger” (hold this below primary). The affected upper eyelid may be:

  • Lower than the contralateral side (aponeurotic ptosis)
  • Higher (“hang-up”) than the contralateral side (simple congenital ptosis)


Congenital ptosis lids will generally have a poorly defined or absent skin crease. Aponeurotic ptosis lids will have deep sulci and a high skin crease. Congenital ptosis may also be associated with monocular elevation palsy or Marcus Gunn jaw-winking syndrome.

Figure 5.4.1 Aponeurotic Ptosis

Figure 5.4.1
Aponeurotic Ptosis

Assess for a Marcus Gunn Jaw-Winking Syndrome

± Ask the patient (especially children) to “Please open your mouth / move your jaw side to side / eat / suck a straw”. Patients with Marcus Gunn Jaw-Winking Syndrome will demonstrate dynamic elevation of the ptotic lid.

Figure 5.4.2
Marcus Gunn Jaw-Winking Syndrome

Figure 5.4.3 Upper Lid Ptosis Secondary to a Lipoma

Figure 5.4.3
Upper Lid Ptosis Secondary to a Lipoma

3. Measurements

  • These are important in determining the cause and management of a ptosis but are less important under examination conditions if the ptosis is thought to be neurological.
  • Levator function is the most important measurement to determine what type of surgery will be performed
  • Holding a pen torch in your right hand and a ruler vertically in the left… ask the patient to:

Instruction

“Look at the torch”
(held in primary)

Measurement

Palpebral Fissure (PF)
Distance between the upper and lower eyelid margins in the pupillary plane.

Normal

8mm (M), 10mm (F)

Marginal Reflex Distance 1 (MRD1)
Distance from upper eyelid margin to corneal reflex.

Normal ~ 4mm
< 2mm = “ptosis”

Instruction

“Look all the way down”

Measurement

Upper Lid Crease (LC)
Distance from the upper eyelid margin (in downgaze) to most prominent crease.

Normal

Normal = 8mm (M), 10mm (F)
(absent / high = aponeurotic)

“I’m going to press quite firmly here” (put torch down, stabilise brow / frontalis muscle with your left hand)

Instruction

“Look all the way up”

Measurement

Levator Function (LF)
Distance that the upper eyelid margin travels in excursion from down to upgaze. The action of the brow must be stabilised.

Normal

≥ 15mm Normal
<10mm Poor
< 5mm Very poor (likely myogenic ptosis, congenital ptosis, CNIII palsy)

Figure 5.4.4 Ptosis Measurements

Figure 5.4.4
Ptosis Measurements

MRD = Margin to Reflex Distance
PF = Palpebral Fissure

4. Lift the Ptotic Eyelid

Manually elevate the ptotic eyelid to see if the contralateral side falls (Herrings law). This is known as “enhanced ptosis” and suggests the presence of bilateral (masked) ptosis. An alternative is to use 10% phenylephrine drops in the ptotic eye to stimulate Muller’s muscle. Masked ptosis in the contralateral eye will be revealed as the ptotic lid elevates

5. Eye Movements

Under exam conditions there is rarely sufficient time to perform cover testing. Proceed to examining ocular rotations with an “H” pattern. Potential causes of ptosis and eye movement disorders include: CNIII palsy, Myasthenia Gravis, Chronic Progressive External Ophthalmoplegia (CPEO), Oculopharyngeal dystrophy, Myotonic dystrophy, Monocular elevation deficit (pseudo-ptosis)

Check for: - Aberrant regeneration (CN III palsy) - Elevation defect (superior rectus weakness in congenital ptosis) - Saccades (slow, hypometric and “glissadic” (gliding) saccades may occur in many neurogenic / myogenic conditions such as Myasthenia gravis and CPEO)

6. Signs of Myasthenia Gravis

i. Cogan’s Lid Twitch

Hold your finger horizontally in the patient’s downgaze and ask them to look at this for several seconds. Hold a pen horizontally in the patient’s primary gaze and ask them to “Look at the pen”. Look for twitch of the upper eyelid on saccade from downgaze to primary. Sometimes the upper eyelid will overshoot, then gradually fall (become more ptotic) - this is also abnormal.

ii. Fatigueability

Hold a pen horizontally in the patient’s upgaze and ask them to “Look at the pen”. Say aloud (to the examiner) “I am looking for fatigueability” (worsening ptosis). As there is usually insufficient time in examinations (ideally the upgaze should be held for 2 minutes), the examiner will often disclose any potential fatigueability to the candidate and ask them to proceed with the rest of the examination.

iii. Orbicularis Oculi

Starting with the patient’s eyes open, use your thumb and index finger of both hands to hold open the upper and lower eyelids of both of the patient’s eyes. Ask the patient to “Close your eyes as hard as you can”. Inability by the patient to overcome your grip and close his / her eyes is suggestive of neuromuscular disease such as Myasthenia Gravis.

7. Assess Risk of Exposure

Eyelid closure may be reduced in neuromuscular disorders. It is also essential to test this as any surgical intervention may risk of corneal exposure. See Section 5.1.6 Corneal Exposure Risk.

8. ± Additional Examination / Tests Depending on Above Findings

  1. Evert the upper eyelid for a mechanical cause (especially if unilateral ptosis)
  2. Slit-lamp examination i. Look for evidence of exposure (with fluorescein staining)
    ii. Look for pigmentary retinopathy (Kearns-Sayre syndrome)
  3. Bulbar musculature i. Ask patient to say “123456789”, “ppp” (CNVII), “kkk” (CNX), “ttt” (CNXII)
    ii. Speech may be affected in Myasthenia Gravis, CPEO, Oculopharyngeal dystrophies and Myotonic Dystrophy
    iii. Look for facial synkinesis following CN VII palsy
  4. Other signs of Horner’s Syndrome (see Section 7.8)
  5. Check old photos (particularly for suspected congenital ptosis)
  6. Check pulse, ECG i. Kearns-Sayre syndrome (look for heart block)
  7. Ice test i. Place covered ice over eyelids for 2 minutes. A 2mm improvement in ptosis after 2 minutes is very sensitive and specific for Myasthenia Gravis.
  8. Phenylephrine 10% test
    i. Stimulate Muller’s muscle (consider in mild ptosis)
    ii. Beware of cardiac complications of this test

Summary

  • Right or left (unilateral or bilateral)
  • Involutional / myogenic / neurogenic / mechanical ptosis
  • ± Good / poor levator function
  • ± Corneal exposure
  • Paediatric ptosis: Check for occlusion amblyopia, jaw-wink, levator function

Aetiology

Inspection

± Chin up position, Brow over-action?

Symmetry

Aponeurotic

Bilateral (but asymmetrical)

Neuromuscular junction (Myogenic)

Bilateral

Neurogenic

Unilateral

Mechanical

Unilateral

Congenital

Unilateral (most)

Lid features

Aponeurotic

Deep sulci,
Lids low on downgaze

Congenital

Lid high on downgaze (congenital) [ii]
± Jaw-wink

Poor relaxation of the levator.

Superior Lid Crease

Aponeurotic

Absent / high (>12mm) [iii]

Neuromuscular junction (Myogenic)

Variable

Neurogenic

Normal

Mechanical

Variable

Congenital

Shallow / absent

If the posterior attachments of the levator aponeurosis to the tarsus detach but the anterior attachments to the skin remain intact, pulling the skin crease superiorly.

Levator Function

Aponeurotic

Normal or only slightly reduced

Neuromuscular junction (Myogenic)

Decreased

Neurogenic

Variable (normal in Horner’s Syndrome)

Mechanical

Variable

Congenital

Decreased

Pupils

Neurogenic

Miosis (Horner’s)
± Mydriasis (CNIII palsy)

Eye movements

Neuromuscular junction (Myogenic)

Often affected
Slowed Saccades

Neurogenic

Features of CNIII palsy

Congenital

May have upgaze (superior rectus) deficit

Typical management

Aponeurotic

Levator advancement /
plication or resection

Neuromuscular junction (Myogenic)

Investigate / manage underlying disease
Rule out Kearn-Sayre Syndrome

Neurogenic

Rule out life-threatening causes
Correct strabismus prior to ptosis

Mechanical

Removal of the mass

Congenital

Brow suspension if adequate frontalis action

Investigations

Investigations are dictated by the provisional cause for the ptosis. Investigations that may be required include:

  1. Orbital Imaging (particularly if proptosis or enophthalmos are present)
  2. Myasthenia Gravis
    1. Antibodies
      1. ACh receptor (“Binding” type in 50% of ocular MG, 90% generalized MG, Specific)
      2. ± Anti-MuSK (muscle specific kinase) (in 20% of AChR negative MG but rare in ocular MG)
    2. Tensilon (edrophonium)
      1. Give 2mg (2mL) IV (test dose, wait 2mins)
      2. Give 8mg (8mL) IV (actual dose)
      3. There is a risk of a cardiovascular arrest. Ensure IV Atropine resuscitation equipment available
      Neostigmine IMI test
      1. Longer-acting, useful in children
    3. Single fibre EMG
      1. Gold standard (99% sensitive) but not very useful in purely ocular myasthenia.
    4. CT chest with contrast
      1. Thymomas are present in 15% of patients with myasthenia gravis
    5. TFTs and TRAB
      1. Association with autoimmune disease and especially Grave’s disease
  3. Mitochondrial myopathies (including CPEO, Kearns-Sayre syndrome)
    1. ⊕ Muscle biopsy (deltoid)
      1. Ragged red muscle fibres represents accumulation of abnormal mitochondria
      2. Serum lactate / CK / glucose
      3. ↑ CSF protein
      4. (-) ACh receptor antibodies, (-) Tensilon
      5. Cardiovascular work up for heart block in Kearn-Sayre Syndrome

          

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