Korean J Otorhinolaryngol-Head Neck Surg.  2017 Oct;60(10):531-534. 10.3342/kjorl-hns.2016.17055.

Isolated Left Trochlear Nerve Palsy Caused by Sphenoid Sinus Mucocele

• Lee P
• Han JS
• Kim YH
• Park SY

• KMID: 2393819
• DOI: http://doi.org/10.3342/kjorl-hns.2016.17055

Abstract

Paranasal sinus mucoceles are an uncommon cause of isolated palsies of cranial nerves III, IV, and VI. The trochlear nerve has been reported to be less frequently affected than the abducens and oculomotor nerves. Isolated sphenoid sinus diseases may cause serious complications by involving adjacent vital structures such as the optic nerve, cavernous sinus, internal carotid artery, and cranial nerves III-VI. We report a case of a 76-year-old woman who presented to our emergency department with a chief complaint of acute double vision and headache. Her diplopia was diagnosed as left trochlear nerve palsy. Brain CT and MRI revealed expanding cystic lesions in both sphenoid sinuses with bony erosion of the left sinus wall. The patient underwent an endoscopic intranasal sphenoidotomy and recovered completely from diplopia at postoperative 2 months. The relationship between the trochlear nerve palsy and its anatomy is also discussed.

Keyword

Diplopia; Forth cranial nerve; Paranasal sinus; Superior oblique muscle; Superior orbital fissure

MeSH Terms

Aged
Brain
Carotid Artery, Internal
Cavernous Sinus
Cranial Nerves
Diplopia
Emergency Service, Hospital
Female
Headache
Humans
Magnetic Resonance Imaging
Mucocele*
Oculomotor Nerve
Optic Nerve
Paralysis
Sphenoid Sinus*
Trochlear Nerve Diseases*
Trochlear Nerve*