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A 54-year-old man presented with a 3-day history of right ptosis and double vision. He was otherwise healthy and did not take any regular medications. Initially, he had horizontal diplopia on the first day that was worse at the end of the day, but this resolved when the right eyelid ptosis became complete. He denied any difficulty with his speech, swallowing, weakness, or sensory changes.
He presented to the emergency department, and the emergency department physician reported a normal neurological examination result apart from the right-sided ptosis and limited eye movements. He was referred to ophthalmology and had a visual acuity of 20/20 OU. Both pupils were equal sizes and reactive to light. He was found to only have a complete limitation of elevation of his right eye and a limitation of abduction in his left eye (Figure). He was orthophoric in primary position, and there were no eyelid twitches. Orbicularis oculi strength was reduced on both sides. A dilated fundus examination had normal results bilaterally. An initial neurological examination, including assessments of motor strength in the upper and lower extremities and reflexes and a sensory examination, had normal results.
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Ocular myasthenia gravis
D. Ice pack test
This patient had new-onset right ptosis with an inability to elevate his right eye and abduct his left eye, with otherwise normal neurologic examination results. This combination of examination findings cannot be localized in the central nervous system, because there is involvement of the levator muscle and superior rectus on the right (innervated by cranial nerve III) and the lateral rectus on the left (innervated by cranial nerve VI). This should raise concern for ocular myasthenia gravis, and a readily accessible test in the clinic is an ice pack test or rest test, which should result in an improvement in the ptosis, as was seen in this patient. His palpebral fissure measured 1 mm before ice was applied and 6 mm 5 minutes after the application of ice. The ice test has been reported to have a sensitivity of 0.94% and specificity of 0.97% in ocular myasthenia1 and is based on the principle that cooler temperatures result in reduced acetylcholinesterase activity.1 It involves placing ice on the involved eyelid for at least 2 minutes and comparing the pretest to posttest measurements. The test is considered to have positive results when there is an increase in the size of the palpebral fissure compared with the pretest measurement.
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Corresponding Author: Jonathan A. Micieli, MD, Kensington Vision and Research Centre, 340 College St, Ste 501, Toronto, ON M5T 3A9, Canada (firstname.lastname@example.org).
Published Online: July 22, 2021. doi:10.1001/jamaophthalmol.2021.0028
Conflict of Interest Disclosures: None reported.
Additional Contributions: We acknowledge Aaron Izenberg, MD, Division of Neurology, Department of Medicine, University of Toronto, for his help in the care of this patient and review of the manuscript. He was not compensated for his contribution. We also thank the patient for granting permission to publish this information.
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