Although physiologic measures demonstrate normal peripheral hearing sensitivity, this patients speech has the inflection and prosodic characteristics associated with profound peripheral hearing loss, and she is unable to understand spoken communication. Behaviorally obtained pure-tone thresholds were variable, ranging from normal to moderate hearing loss with normal middle ear muscle reflexes and normal ABRs to high- and low-intensity stimuli. Auditory middle latency and cortical evoked potentials were grossly abnormal, consistent with the central nature of cortical deafness. Because of her inability to communicate auditorily, this patient was ultimately taught American Sign Language and educated at the Louisiana School for the Deaf. At the completion of the case study, the patient was married and expecting a child. A more recent study, published in 2013 the patient described is a 56-year-old woman a history of hypertension, hypercholesterolemia, and multiple cerebrovascular accident (CVA) who presented in March 2009 with a complaint of complete bilateral hearing loss. In March 2009, she experienced an acute right-sided insulotemporal intracerebral hemorrhage. Immediately after this event, the patient complained of hearing loss with the inability to hear all sounds except for severe bilateral tinnitus. Imaging revealed sequelae in the left cerebral cortex from her previous CVA. The new right-sided hemorrhage was centered on the posterior putamen with surrounding edema involving the posterior portion of the posterior limbs of the internal, external, and extreme capsules. Signal abnormalities extended into the right temporal lobe. The patient had no other neurologic deficits and spoke fluently, although with poor internal volume control of her voice.
Consequently, there will typically be not as much increase in muscle strength observed after edrophonium injection, if any with LEMS. The Tensilon test may also be used to predict if neurotoxic paralysis caused by snake envenomation is presynaptic or postsynaptic. If it is a postsynaptic then paralysis will be temporally reversed, indicating that can be reversed by adequate antivenom therapy. If the neurotoxic is presynaptic then the Tensilon test will show no response and antivenom will not reverse such paralysis. In this instance reversal of paralysis will not occur until the damaged terminal axons at the neuromuscular junction have recovered, this may take days or weeks.The drug may also be used for reversal of neuromuscular blockade at the end of a surgical procedure. Chemistry
Edrophonium, ethyl-(3-hydroxyphenyl)dimethylammonium chloride, is made by reacting 3-dimethylaminophenol with ethyl bromide, which forms ethyl(3-hydroxyphenyl)dimethylammonium bromide, the bromine atom of which is replaced with a chlorine atom by reacting it with silver chloride, giving edrophonium. Pharmacokinetics
The drug has a brief duration of action, about 10–30 mins. References


== Further reading ==