Blepharoptosis is a condition in which the MRD-1 (margin reflex distance-1: distance from corneal light reflex to upper eyelid margin) is ≤3.5 mm due to dysfunction of the levator palpebrae superioris muscle, its aponeurosis, or Müller’s muscle. Normal MRD-1 is 3.5–5.5 mm.
Severity is classified by MRD-1 as follows:
| Severity | MRD-1 | Upper eyelid position |
|---|---|---|
| Mild | Approximately 2–3.5 mm | Covers about 1/3 of the upper half of the cornea |
| Moderate | Approximately 0 to 2 mm | Covers about two-thirds of the upper half of the cornea |
| Severe | Less than 0 mm | Covers the center of the cornea |
MRD-2 is the distance from the corneal light reflex to the lower eyelid margin and is used for lower eyelid assessment. It is important to evaluate using MRD-1 rather than the vertical width of the palpebral fissure.
The prevalence of ptosis in adults is reported to be 4.7–13.5%, and the incidence increases with age 2).
The following table shows characteristic findings by cause.
| Cause | Characteristic Findings |
|---|---|
| Aponeurotic | Abnormal eyelid crease, eyebrow elevation, forehead wrinkles, superior sulcus deformity |
| Myasthenia gravis | Diurnal variation (worse in evening), positive ice pack test, fatigue phenomenon |
| Oculomotor nerve palsy | Pupil dilation, diplopia, exotropia and hypotropia |
| Horner syndrome | Miosis, blepharoptosis (about 2 mm drooping), anhidrosis |
| Congenital | Widening of the palpebral fissure on downgaze (associated with superior rectus lag) |
Blepharoptosis is broadly classified into congenital (90% due to levator muscle dysplasia) and acquired. Among acquired cases, involutional aponeurotic ptosis is the most common, followed by oculomotor nerve palsy, Horner syndrome, myasthenia gravis, and chronic progressive external ophthalmoplegia (CPEO). Differentiation from pseudoptosis (e.g., dermatochalasis, thyroid eye disease) is also important.
Congenital
Levator muscle dysplasia: Congenital degeneration of the levator palpebrae superioris accounts for 90%. Unilateral in over 70%.
Simple: Isolated occurrence.
Complex: Associated with blepharophimosis syndrome or Marcus Gunn phenomenon (trigeminal-oculomotor synkinesis).
Acquired (Aponeurotic)
Most common cause: Aging, contact lens use, or after intraocular surgery (use of lid speculum).
Pathophysiology: Thinning and stretching of the aponeurosis reduces the lifting force on the tarsal plate.
Features: Elevation, irregularity, or loss of the upper eyelid crease, and superior sulcus deformity.
Acquired (neurogenic)
Oculomotor nerve palsy: Associated with mydriasis and diplopia. Rule out cerebral aneurysm (IC-PC aneurysm).
Horner syndrome: Ptosis of about 2 mm due to Müller muscle palsy. Accompanied by miosis and anhidrosis.
Fisher syndrome: Triad of external ophthalmoplegia, ataxia, and areflexia.
Acquired (myogenic and pseudoptosis)
Myogenic: Myasthenia gravis (diurnal variation), CPEO, myotonic dystrophy.
Pseudoptosis: Dermatochalasis (MRD ≥ 3.5 mm), thyroid eye disease (contralateral lid retraction), facial nerve palsy, microphthalmos, anophthalmos.
Aponeurotic ptosis accounts for the majority of acquired ptosis and is more common in women over 60. It is frequently observed in contact lens wearers and after cataract surgery. Approximately 70% of initial symptoms of myasthenia gravis are ptosis2).
Measure the distance from the corneal light reflex to the upper eyelid margin. To eliminate compensation by the frontalis muscle, gently press the forehead with a finger. Normal value is 3.5 to 5.5 mm.
With the patient looking downward, set the upper eyelid margin position as 0 mm, then measure the position when looking upward. Press down on the eyebrows to eliminate compensation by the frontalis muscle. Normal value is 10 mm or more; less than 4 mm indicates severe levator function impairment.
Observe whether the contralateral eyelid droops when the affected upper eyelid is manually elevated. This is important for assessing the risk of manifesting contralateral ptosis after unilateral surgery.
Acute-onset ptosis may indicate a cerebral aneurysm (especially IC-PC aneurysm). If accompanied by dilated pupil or double vision, semi-urgent management is needed. Seek immediate ophthalmology or neurology consultation.
Surgical indications for congenital ptosis:
Surgical indications for acquired ptosis:
When objective findings (decreased MRD-1, abnormal eyelid crease, eyebrow elevation, forehead wrinkles) and subjective symptoms (heavy eyelids, superior visual field defect, eye pain, shoulder stiffness) are consistent, and surgery is expected to improve both.
The basic principle is to select the surgical technique based on levator function.
Levator function ≥10 mm → Levator advancement (levator aponeurosis advancement):
Levator function less than 4 mm → Frontalis sling:
The materials used are as follows:
In children, reoperation is often needed due to growth, and nylon thread is a good indication because it has few complications and returns to the preoperative state if removed. For adults with stable skeletal and muscle conditions, Gore-Tex® sheets are often used.
Congenital (pediatric) surgical techniques:
The surgical procedure is selected based on levator function. For levator function of 10 mm or more, levator advancement is chosen; for less than 4 mm, frontalis suspension is selected. In congenital pediatric cases, reoperation may be necessary with growth, and initial suspension using nylon sutures is often chosen.
Oxymetazoline 0.1% ophthalmic solution is a conservative treatment that contracts Müller’s muscle in the upper eyelid as an α1-adrenergic receptor partial agonist, correcting acquired ptosis.
It is indicated for acquired ptosis (including mild, moderate, and severe). If the cause is neurological disease, tumor, or trauma, evaluation and treatment of the underlying disease should be prioritized, and care should be taken not to obscure the primary disease with this agent 1).
Criteria for administering physician1): ① Board-certified ophthalmologist of the Japanese Ophthalmological Society or the Japanese Board of Ophthalmology, ② Ability to manage adverse reactions.
Usage: Instill one drop in the affected eye once daily (single-use vial formulation). The effect lasts approximately 8 hours after instillation. It provides temporary improvement and is not a curative treatment 3).
When using contact lenses: Remove contact lenses before instillation and wait at least 15 minutes before reinsertion. When used concomitantly with other eye drops, maintain an interval of at least 15 minutes.
If no effect is observed, do not continue indiscriminately; investigate the cause and consider other treatments 1). Use for cosmetic purposes is not permitted.
The efficacy of Upneeq was verified in two phase 3 RCTs (total 304 patients, 2:1 randomized double-blind placebo-controlled). The change in LPFT (difference from placebo) is shown below 3).
| Evaluation time point | Study 1 | Study 2 |
|---|---|---|
| Day 1, 6 hours post-dose | Difference 3.7 points | Difference 4.2 points |
| Day 14, 2 hours after | Difference 4.2 points | Difference 5.3 points (both p<0.01) |
MRD1 also showed significant improvement 3).
It is not a curative treatment but a conservative therapy that provides temporary improvement for about 8 hours with once-daily instillation. It is used when surgery is not desired or as a bridge to surgery. If no effect is observed, it should not be continued indefinitely; other treatments including surgery should be considered.
Age-related degenerative changes and mechanical irritation from long-term contact lens use cause the aponeurosis to stretch and thin (muscle fibrosis). Subcutaneous perforating vessels are no longer pulled in, and the eyelid crease disappears. Sustained compensatory contraction of the frontalis muscle can lead to tension headaches and neck-shoulder pain.
It has a two-layer structure: an anterior layer (thick) originating slightly distal to Whitnall’s ligament and a posterior layer (thin, inserting into the lower third of the tarsus). Subcutaneous perforating vessels form the eyelid crease.
Congenital degeneration (fibrosis) of the levator palpebrae superioris muscle reduces lifting power. The palpebral fissure widens on downgaze due to poor eyelid following (lid lag), and Marcus Gunn phenomenon may be associated.
Müller’s muscle is a sympathetically innervated smooth muscle that provides about 2 mm of eyelid elevation. In Horner syndrome, paralysis of this muscle results in approximately 2 mm of ptosis.
As an α1-adrenoceptor agonist, it binds to α receptors in Müller’s muscle of the upper eyelid, promoting muscle contraction and lifting the eyelid. In involutional ptosis, the levator aponeurosis is mainly affected, but Müller’s muscle function often remains, providing a compensatory lifting effect. This is the same principle as the effectiveness of Müller’s muscle resection for ptosis associated with Horner syndrome.
