Dufek MA, Shechtman DL. Floppy eyelid syndrome: a diagnostic dilemma. J Am Optom Assoc 1999; 70:450-454. Dutton JJ. Surgical management of floppy eyelid syndrome. Am J Ophthalmol 1985; 99:557-560. Klapper SR, Jordan DR. Floppy eyelid syndrome. Ophthalmology 1998; 105:1582.
Langford JD, Lindberg JV. A new physical finding in floppy eyelid syndrome. Ophthalmology 1998; 105:165-169. Liu DT, Di Pascuale MA, Sawai J, Goa YY, Tseng SC. Tear film dynamics in floppy eyelid syndrome. Invest Ophthalmol Vis Sci 2005; 46:1188-1194.
McNab AA. Reversal of floppy eyelid syndrome with treatment of obstructive sleep apnea. Clin Experiment Ophthalmol 2000; 28:125-126.
McNab AA. Floppy eyelid syndrome and obstructive sleep apnea. Ophthal Plast Reconstr Surg 1997; 13:98-114. McNab AA. Floppy eyelid syndrome. Ophthalmology 1998; 105:1977-1978.
Periman LM, Sires BS. Floppy eyelid syndrome: a modified surgical technique. Ophthal Plast Reconstr Surg 2002; 18:370-372. Schlotzer-Schrehardt U, Stojkovic M, Hofmann-Rummelt C, et al. The pathogenesis of floppy eyelid syndrome: involvement of matrix metaloproteins in elastic fiber degeneration. Ophthalmology 2005; 112:694-704. Valenzuela AA, Sullivan TJ. Medial upper eyelid shortening to correct medial eyelid laxity in floppy eyelid syndrome: a new surgical approach. Ophthal Plast Reconstr Surg 2005; 21:259-263.
INTRODUCTION Hemifacial spasm is characterized by involuntary unilateral hyperkinetic tonic and clonic spasms of muscles innervated by the seventh cranial nerve. In contrast with essential blepharospasm, in hemifacial spasm muscle contractions continue during sleep. An anatomic cause appears to be responsible in most cases. In 85% to 90% of cases an abnormal ectatic vascular loop of the vertebral-basilar arterial tree can be seen on MRI compressing the seventh nerve exit root in the cerebellopontine cistern. Most frequently the anteriorinferior cerebellar artery is involved. Rarely, bilateral cases have been described, but the two sides are typically not involved synchronously or to the same degree. In very rare instances compression of the seventh nerve by tumor, aneurysm, or other mass lesions may be the cause. Peripheral seventh nerve injury from trauma or Bell's Palsy can also result in hemifacial spasm following axonal regeneration. A case of hemifacial spasm associated with otitis media has been reported. Arterial hypertension occurs significantly more frequently in patients with hemifacial spasm suggesting a causal relationship. Hemifacial spasm generally occurs in older adults, but rarely can be seen in children.
CLINICAL CHARACTERISTICS In classic hemifacial spasm contraction of facial muscles often begins with the orbicularis muscle followed by subsequent downward progression over the face. In atypical cases, the onset of symptoms is in the buccal muscles, with upward progression. The difference appears to be caused by the specific vessels involved in the compression. The average age at onset for hemifacial spasm is 45 years with a slight preponderance of females. The condition typically begins with intermittent twitching of one eyelid which progresses over months to years to involve other areas of the ipsilateral facial nerve innervation. In its full-blown state hemifacial spasm involves closure of the eyelids associated with contraction of the entire ipsi-lateral face and elevation of the mouth.
TREATMENT Anticonvulsants, such as carbamazepine, may be helpful in some cases, as are the short-acting benzodiazepines. But these are useful in only about one-fourth of cases with mild symptoms. The most effective treatment currently available is chemodenervation with botulinum toxin. The latter blocks neuromuscular transmission by preventing degranulation of acetylcholine at peripheral cholinergic nerve endings. The duration of effect is typically three to four months. Complications include transient ptosis, mouth droop, and other muscle weaknesses. Microvascular decompression of the seventh nerve root where it exits the brain stem is an effective surgical treatment in most cases, with about 70% to 89% of cases showing complete relief of spasms. Potential complications include hearing impairment and CSF leak, and the mortality rate is reported at 0.3% to 0.6%. Monitoring of abnormal muscle response intraoperatively may enhance the final result.
Was this article helpful?