Revisiting two clinical techniques for diagnosing myasthenia gravis in Covid times: Pointing to semiology

Abstract

As it has been evident in these times of the Covid-19 pandemic, the majority of health resources have
been focused to the acute treatment, vaccination or research to this condition. By these reasons, some
confirmatory complementary tests in many pathologies cannot be made or are postponed, including
Myasthenia Gravis. Two clinical neurological signs useful for diagnosis of Myasthenia Gravis are
revised: the “Curtain Sign” (also called paradoxical ptosis), that is evoked opening the more closed eye,
which results in a dropping of the contralateral eyelid; and the Mary-Walker maneuver, which results
from repetitive pronation-supination exercise under anaerobic conditions in one or both arms resulting
in increasing of bilateral ptosis. The importance of a presumptive early diagnosis of Myasthenia Gravis
is the early onset of specific treatment even when it’s impossible to carry out complementary studies like
single-fiber electromyography, thoracic images, or specific immune studies. .