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Review of Symptoms:
Part VIII
Playing it Safe with
Tics and Ptosis
Twitching or drooping lids sometimes signal
serious problems. Here’s how you can distinguish among symptoms to
discover the underlying cause.
Joseph W. Sowka, O.D. Alan G. Kabat, O.D.
Contributing Editors
Sidebars:
Eyelid problems are a common source
of alarm for patients. Unfortunately, a wide range of etiologies also makes the
“twitchy” or “droopy” eyelid confusing for us as
practitioners. Lid twitching has numerous causes, some benign and others
potentially serious. Similarly, ptosis can occur as a normal aging change, or
it may signal an underlying systemic or neurological dysfunction. This eighth
installment of our “Review of Symptoms” series will explain the many
causes for lid disorders.
Lid Twitch
A patient who
can’t control lid fluttering or twitching can find it very distressing.
Often this condition is a simple, benign muscle anomaly, but on occasion it can
represent a severe neurological disorder. Consider the following:
- Benign myokymia. Patients
often describe this common condition as a twitching or “jumping” of
the eye. In fact, it involves only the eyelid. Without a concurrent complaint
of visual oscillopsia, you can discount actual globe movement. Because
nystagmus is a very different condition with potentially far more serious
ramifications, it’s important to pointedly ask this question: “Is it
your eye or eyelid that’s twitching?"
Ask your patient if he or she has
noticed the eyelid movements when looking in the mirror, or if others have
noticed it. Typically, the lid twitching that occurs with benign lid myokymia
is so subtle that the patient senses it, but others rarely see it. The patient
may feel that the phenomenon causes lid drooping but, again, this is rarely
noticeable.
Benign myokymia presents in
otherwise healthy individuals. It’s typically unilateral, but may
alternate sides in recurrent cases. It may involve the upper or lower lids. The
twitching may occur intermittently for hours or weeks. The etiology remains
obscure, but is frequently associated with psychological stress or significant
ingestion of caffeine and/or nicotine. Reassure the patient that the condition
is transient and benign. The best treatment is to reduce the precipitating
factors. However, in more symptomatic or persistent cases, drug therapy may be
indicated (see “Treating Lid Myokymia,” page 76).
- Essential blepharospasm. This
more serious condition involves involuntary contraction of the orbicularis
oculi muscles, resulting in forced closure of both eyelids. These spasms occur
spontaneously, but they have also been associated with stress and bright
lights. Bilateral blepharospasm can be associated with keratitis,
Parkinson’s disease, myotonic dystrophy, Huntington’s chorea, tardive
dyskinesia or Meige’s syndrome.
Patients who demonstrate bilateral
blepharospasm without these conditions have essential blepharospasm. While
supranuclear dysfunction may be the cause, this condition historically has been
ascribed to a psychogenic etiology. However, clinicians today consider this a
real neurological condition, the etiology of which remains elusive. While
seemingly harmless, some patients cannot perform day-to-day activities. We know
of one patient who had a serious automobile accident because of essential
blepharospasm.
- Hemifacial spasm. This
manifests as frequent, involuntary contractions of the muscles on one side of
the face. It’s a neurological disorder that is typically encountered in
patients aged 50 and older. Women may be affected more often than men. Usually,
the initial symptom is intermittent lid twitching, followed by forced lid
closure. The spasm may then gradually spread to involve the lower face, pulling
the mouth laterally. Eventually, the spasms become continuous and involve all
the muscles on the affected side of the face.
Hemifacial spasm most
commonly results from mechanical irritation of the seventh nerve roots by a
dilated vascular structure. However, a compressive tumor, such as pontine
glioma, is the etiology in about 1% of these patients.1 So, all
patients with hemifacial spasm require brain MRI with contrast, paying
particular attention to the pontomedullary junction.
- Marcus Gunn jaw wink. Aberrant
connections of nerves to muscles cause this congenital synkinetic response. The
pterygoid nerve (V3), which naturally innervates the jaw muscles involved in
chewing, inappropriately innervates the ipsilateral levator muscle. This
results in a ptosis that alleviates with jaw movement. When the patient opens
his or her mouth, the upper lid elevates slightly. When he closes his mouth,
the ptosis returns. When the patient moves the jaw from side to side while
chewing, the lid elevates more noticeably, especially when the jaw moves to the
opposite side. This gives the superficial appearance of winking. A congenital
abnormality, this condition is an untreatable anatomical curiosity.
Overlooked Condition
Often, ptosis is overlooked or dismissed as a
congenital defect or a consequence of aging. While this may be true, ptosis
also sometimes represents life-threatening neurogenic or neuromuscular disease.
To differentiate among various forms of ptosis, you must consider whether it
affects one or both eyes. Unilateral ptosis often stems from underlying
disease, while bilateral ptosis typically associates with generalized muscle
disorders or aging. Associated signs may also help to identify the specific
disorder. Some etiologies of ptosis:
- Acquired mechanical ptosis.
Patients in their 60s, 70s, and beyond often develop ptosis due to normal
senescent changes in lid structure. Most commonly, local dehiscence and
disinsertion of the levator aponeurosis is the root cause of lid drooping.
Dermatochalasis also may be an etiology of ptosis in these patients.
This condition manifests clinically as redundant, sagging skin of the upper
lids. Patients with dermatochalasis often lose the normal lid crease due to
herniation of orbital fat through the septum orbitale.
Blepharochalasis
is another lid condition that presents with ptosis. Because of the
nomenclature, clinicians often confuse blepharochalasis with dermatochalasis,
or use the terms interchangeably. However, true blepharochalasis stems from
recurrent attacks of eyelid edema, which ultimately results in damage to the
aponeurosis.2 This condition may be unilateral or bilateral, and can
appear in patients of any age. Dermatochalasis is almost always bilateral and
is rarely a symptomatic concern in patients under 50.
- Horner’s syndrome. The
clinical triad of ptosis, miosis and anhydrosis marks Horner’s syndrome.
Branches from the oculosympathetic neural plexus control the pupil’s
radial (dilator) muscle as well as the eyelid’s Müller’s
muscles. Because of the long course of the oculosympathetics, there are many
areas where damage can occur, from the hypothalamus down to the thoracic area
and back up to the orbit. The most telling diagnostic sign of Horner’s is
anisocoria (the pupil on the involved side is smaller). This appears greater in
dim illumination. There also will be a slight ipsilateral ptosis. And, both the
upper and lower lids may be involved: the upper will droop downwards, the lower
will drift upwards. While extensive pharmacological tests are required to
definitively diagnose Horner’s syndrome, you must suspect any patient
manifesting a ptosis with ipsilateral miosis (see box below).
- Bell’s palsy. This
paralysis of the seventh cranial nerve, which controls the facial expression
muscles, results from nerve inflammation. It has a rapid onset; cases may
manifest over 2-5 days or even overnight. Bell’s palsy most commonly
affects only one side of the face, but it can be bilateral in some instances.
Patients are typically over 40, and it affects both sexes equally.
By
definition, Bell’s palsy is idiopathic; facial nerve palsy may otherwise
be attributable to trauma, compression, viral infection, chronic otitis media,
hypertension, diabetes, sarcoidosis and Lyme disease. The associated paralysis
may be temporary or permanent, and the severity varies greatly from patient to
patient. However, 85-90% of Bell’s palsy cases resolve without
intervention within 2-3 weeks of onset.3
Because Bell’s
palsy affects the orbicularis oculi muscle, patients demonstrate a drooping of
the upper lid as well as lower lid ectropion. In contrast to other forms of
ptosis, patients with Bell’s may actually exhibit a widening of the
palpebral fissure. They commonly complain of dryness because the lids
don’t close or blink completely. Associated signs include an inability to
raise the eyebrow, and smile or puff out the cheek on the affected side.
Although most cases resolve completely, about 10% of patients will experience a
recurrence on the contralateral side of the face.3
- CN III palsy. The third
cranial nerve (oculomotor) is responsible for innervating the medial rectus,
superior rectus, inferior rectus and the inferior oblique muscles. In addition,
CN III innervates the levator palpebrae superioris muscle of each eyelid.
Damage to this nerve results in ophthalmoplegia with associated diplopia due to
inaction of these muscles. An inability to elevate or adduct the eye causes the
eye to assume a “down and out” posture. Ptosis typically accompanies
this presentation because the fibers from the central caudal nucleus that
innervate the levator are disrupted.
Curiously, the onset of ptosis may
prevent patients from experiencing diplopia related to the ophthalmoplegia.
Remember that the ptosis in CN III palsy always coincides with extraocular
muscle paralysis; it does not occur in isolation without ophthalmoplegia. The
ophthalmoplegia does not have to be a complete palsy with the eye assuming a
“down and out” position, but may be a palsy with only subtle muscle
underaction. Also, unilateral CN III palsy always occurs due to damage along
the course of CN III from the brainstem to the orbit. Should damage occur
directly to the sub-nuclear complex of CN III within the brainstem, a bilateral
ptosis with unilateral ophthalmoplegia will occur because one central caudal
nucleus innervates both levator muscles.
- Myasthenia gravis. Few
conditions are associated more with acquired ptosis than this autoimmune
disease, which affects as many as 1 in 20,000 individuals.4 However,
due to its ability to mimic other ocular conditions, it is often
under-diagnosed. Patients who have MG develop antibodies to the acetylcholine
receptors on the motor end plates of skeletal muscles. So, acetylcholine
can’t act to generate an electrical nerve impulse. While systemic MG can
produce life-threatening effects, including difficulty in swallowing and
breathing, the condition sometimes may affect only those muscles associated
with ocular function.
Ptosis is the
most notable ocular finding in MG. The ptosis is variable in that it can
improve or disappear with rest, and will exacerbate with fatigue. In fact,
increasing ptosis with sustained upgaze is a hallmark of MG. Also, the ptosis
has a predilection to alternate between sides. Other common associated findings
include intermittent diplopia that varies with regard to both severity and
involved extraocular muscles. Definitive testing for MG is somewhat involved,
although some in-office techniques can be useful (see box below).
While twitching and
drooping eyelids are common complaints, they are sometimes serious and may be
associated with other disorders. Careful review of symptoms will help you
distinguish between severe and benign causes so that you can employ the
appropriate testing and treatment. u
Drs. Sowka and Kabat
are on faculty at the Nova Southeastern University College of Optometry, Ft.
Lauderdale, Fla. Next month: visual field loss.
- Sprik C, Wirtschafter JD.
Hemifacial spasm due to intracranial tumor. An international survey of
botulinum toxin investigators. Ophthalmology 1988;95:1042-5.
- Ellis, FD. Correction of
blepharoptosis in children. In: Tasman W, Jaeger EA, eds. Duane’s
Ophthalmology, 1996 CD-ROM edition. Lippincott-Raven: Philadelphia, 1995.
- Peitersen E. The natural history
of Bell’s palsy. Am J Otol 1982;4:107-11.
- Zion VM, Billet E. Musculoskeletal
disorders. In: Tasman W, Jaeger EA, eds. Duane’s Ophthalmology, 1996
CD-ROM ed. Philadelphia: Lippincott-Raven, 1995.
- Tomsak RL, Costin JA, Levine MR.
Eyelid and facial disorders. In: Parrish RK, ed. Atlas of Ophthalmology.
Boston: Butterworth-Heinemann, 2000:472-9.
- Bartlett JD, Melore GG. Diseases
of the eyelids. In: Bartlett JD, Jaanus SD, eds. Clinical Ocular Pharmacology,
3rd edition. Boston: Butterworth-Heinemann, 1995:561-600.
- Borenstein S, Desmedt JE. Local
cooling in myasthenia. Improvement of neuromuscular failure. Arch Neurol
1975;32:152-7.
- Golnik KC, Pena R, Lee AG,
Eggenberger ER. An ice test for the diagnosis of myasthenia gravis.
Ophthalmology 1999;106:1282-6.
- Sethi KD, Rivner MH, Swift TR. Ice
pack test for myasthenia gravis. Neurology 1987;37:1383-5.
Treating Lid Myokymia
Most times, patients with benign
myokymia require little more than reassurance because the condition abates
spontaneously within a few days. However, those rare individuals who have
persistent or highly symptomatic bouts may benefit from therapy. Topical
antihistamines, such as antazoline or pheniramine, may prolong the refractory
period of the orbicularis oculi muscle, alleviating symptomatic myokymia within
20 minutes of instillation.6 Anecdotally, the quinine in tonic water
may also help calm this condition. One to two glasses a day for a week is often
helpful, but avoid this therapy in pregnant women. |
| Causes of Acquired Ptosis5 |
| Myogenic |
- Myasthenia gravis
- Progressive external ophthalmoplegia
- Late acquired hereditary ptosis
- Corticosteroid-induced ptosis
|
| Aponeurotic:
|
- Levator dehiscence
- Blepharochalasis
|
| Neurogenic:
|
- Horner’s syndrome
- Oculomotor palsy
- Facial palsy
- Multiple sclerosis
- Ophthalmic migraine
- Vascular Compressive/Tumor
|
Traumatic:
|
- Eyelid laceration
- Post-surgical ptosis
- Orbital fracture
- Foreign body
|
| Mechanical: |
- Dermatochalasis
- Lid tumor
- Cicatricial ptosis
|
Testing for Horner’s Syndrome
Suspect
Horner’s syndrome in any patient who presents with unilateral ptosis and
miosis. While perhaps it’s difficult to acquire, testing with topical
cocaine will rule out Horner’s (you may use 4% solution, but most
clinicians prefer 10% concentration). Instill one drop into each eye, and
re-evaluate the pupils in 45 minutes. If both pupils dilate with cocaine, the
patient has a physiological anisocoria. If the pupil in question fails to
dilate, a true Horner’s syndrome exists.
Additional testing can determine the
level of the neurological lesion. On another day after cocaine testing, instill
one drop of 1% hydroxyamphetamine in each eye. Wait 45 minutes. If the
concerned pupil dilates, the lesion is preganglionic (i.e., located somewhere
between the thalamus and the superior cervical ganglion). If the pupil
doesn’t dilate, the lesion is postganglionic. This is important;
preganglionic lesions most often involve compression at the level of the
mediastinum, such as from an apical lung tumor. Hypothalamic disease can also
instigate a preganglionic Horner’s. Postganglionic lesions are far less
ominous because, typically, they’re congenital, traumatic or induced by
migraine. |
Testing for Myasthenia Gravis
Historically, definitive testing for
myasthenia gravis has involved injectable anticholinesterase drugs such as
Tensilon (edrophonium chloride) which, in a positive test, causes the ptosis or
ophthalmoplegia to improve. An assay for acetylcholine receptor antibodies is
also popular and safer than Tensilon—but can be quite costly.
A novel, safe and
inexpensive office test that doctors sometimes utilize in MG is the ice pack
test. This works like injectable anticholinesterase drugs. It cools the enzyme
responsible for degrading acetylcholine, rendering the enzyme dysfunctional,
and allows acetylcholine a better opportunity to compete against the abnormal
antibodies.7 To conduct this test, place an ice pack over the ptotic
eyelid for 2 minutes. If the degree of ptosis lessens, consider this highly
diagnostic for MG. Studies have demonstrated a remarkably high sensitivity for
the ice pack test in MG-induced ptosis.8,9 Many specialists prefer
to perform this test prior to or in lieu of Tensilon injection. |
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