|
Ptosis (also
known as blepharoptosis) is
drooping of the upper eyelid. It
can be the result from both congenital and acquired
abnormalities of the
muscles that serve to raise the eyelid.
Basic Anatomy:
Some of
the
various different muscles that surround the palpebral
fissures include the
orbicularis oculi, the levator palpebrae superiors,
and the Müller's
muscle.
1. The
orbicularis oculi muscle surrounds the circumference
of the eye and serves to
close both the upper and lower eyelid.
It is innervated by the seventh cranial nerve
(facial).
2. The
levator
palpebrae superiors muscle helps to raise the upper
eyelid. It
is innervated by the third cranial
nerve (oculomotor).
3. The
Müller's
muscle is an accessory smooth muscle that serves to
help elevate the upper
eyelid. It
is innervated by the
sympathetic nervous system.
History and
Physical Examination:
Obtaining
a
good history can help reveal the etiology and lead to
a correct diagnosis.
It is important to investigate the
timing, duration, and progression of the ptosis as
well as associated
symptoms. Asking
the patient or
patient’s family members to show photographs of the
patient prior to
development of symptoms can help the clinician
appreciate the degree of ptosis
as well.
Some
questions
you may want to ask include:
- When
did you first notice that your eyelid start to
droop? Alternatively,
has it been present since birth?
- Are
both eyes drooping or just one?
- Did you
notice that your eyelids have been progressively
drooping (or feeling heavier) or did this process
seem to happen immediately?
- Do you
notice that the degree of ptosis changes during
different times of the day? Or under different
settings?
- Have
you experienced any recent trauma?
- Do you
have blurry vision?
Vision problems?
- Do you
have a history of eye surgery?
- Do any
other members of your family experience similar
symptoms?
- Any
other symptoms that you notice besides the ptosis?
On
examination,
the clinician should pay attention to how the head is
postured and eyebrow is positioned. Some
patients may adapt a “chin up”
position and raise their eyebrows in an attempt to
maintain vision.
Also take notice of eyelid position,
pupil size and reactivity, and extraocular movements. The clinician should also
perform a detailed neurologic
examination.
Etiology:
Congenital:
- Congenital ptosis is
usually unilateral and does not progress. It is
associated with absence or diminution of the levator
palpebrae superiors muscle. Other
ophthalmologic findings may include amblyopia and
strabismus.
- Congenital
orbital fibrosis is an autosomal dominantly
inherited condition that produces fibrosis of the
extraocular muscles that consequently limits eye
movements and has associated ptosis. Addtionally,
blepharophimosis
(another autosomal dominantly inherited
condition) is associated with severe bilateral
ptosis.
- Congenital
Horner's syndrome due to birth trauma can display
ptosis of the affected eye.
- Marcus
Gunn jaw winking: abnormal innervations of the
levator muscle by the mandibular branch of the
trigeminal nerve causes eyelid retraction when the
patient contracts the pterygoid muscle during the
acts of sucking or jaw movement.
- Infantile
myasthenia gravis, Surge Weber, von Recklinghausen
syndrome, and fetal alcohol syndrome can all
generate ptosis.
Mechanical:
- Mechanical
ptosis can result from excessive weight on the upper
lid. Sources
include infections, inflammation, and eyelid tumors.
Neurologic:
- Any
disease that affects the neurologic system
(including the brainstem, cranial nerves,
neuromuscular junction, muscle, peripheral nerves,
etc.) can create ptosis.
- Third
cranial nerve (oculomotor) palsy will result in
ptosis, opthalmoplegia and diplopia. Lesions
anywhere on the path between the oculomotor nucleus
in the midbrain and the extraocular muscles within
the orbit can cause third nerve palsy.
- Horner’s
syndrome is any dysfunction to the sympathetic
nervous system that results in ipsilateral ptosis,
mitosis, and anhidrosis. In
children, Horner's syndrome can lead to
heterochromia (a difference in eye color between
the two eyes.)
- Neuromuscular
junction disorders such as botulism and myasthenia
gravis often produce ptosis.
- Myasthenia
gravis is an autoimmune disorder in which antibodies
are directed against postganglionic acetylcholine
receptors in the neuromuscular junction of voluntary
muscles. Isolated ocular findings present initially
in approximately half of the cases. Unilateral or
bilateral ptosis can develop with/without diplopia
along with other ocular motor dysfunctions.
Infantile myasthenia gravis occurs when antibodies
are transferred to the neonate by the mother with
myasthenia gravis.
- Ptosis
can be the result of infectious botulism.
- Myogenic
are muscle disorders, such as mitochondrial myopathy
and moronic dystrophy, can present with ptosis.
Pseudoptosis:
- Pseudoptosis
is when the eyelid falsely appears to be ptotic but
the primary pathology may not involve the lid.
- Some
conditions that can display pseudoptosis include an
enophthalmic eye (lack of posterior support),
hypotropic eye (droop disappears when affected
patient fixates on an object with the eye), and lid
retraction of one eye (ptosis seems to come into
view in the contralateral eye).
Management:
Managing ptosis can include
nonsurgical and/or surgical
therapy depending on the underlying pathology.
Nonsurgical
therapy:
- In
cases where the ptosis can be attributed to
myasthenia gravis, medical therapy is considered the
gold standard.
Surgical
therapy:
- Surgery
is indicated mainly in patients who have an obscured
visual field due to ptosis. Obscured vision in
infants may lead to amblyopia; thus, making surgery
the treatment of choice.
- Surgery
can also be employed for cosmetic reasons.
- Surgical
approaches to the improvement of ptosis include
Müller muscle resection, levator muscle
resection or advancement, and frontals suspension. The
surgical method chosen is individually determined.
References:
1. Fosterer J. Ptosis: causes, presentation, and
management. Aesthetic
Plast Surg 2003; 27:193.
2. Toyka KV. Ptosis in myasthenia gravis:
extended fatigue and recovery
bedside test. Neurology 2006; 67:1524.
3. Johnson CC. Congenital ptosis. In: Principles
and Practice of
Ophthamology, Jakobiec FA, Albert DM. (Eds), WB
Saunders Co, Philadelphia 1994.
p.2839.
4. Ahmadi AJ, Sires BS. Ptosis in infants and
children. Int Ophthalmol
Clin 2002; 42:15.
5. Kersten RC, de Conciliis C, Kulwin DR.
Acquired ptosis in the young
and middle-aged adult population. Ophthalmology 1995;
102:924.
|