Diminished discriminant sensibility can be measured by testing two-point discrimination: the number of millimeters two points of contact need to be separated before you can distinguish them.A person with idiopathic median neuropathy at the carpal tunnel will not have any sensory loss over the thenar eminence (bulge of muscles in the palm of hand and at the base of the thumb). This is because the palmar branch of the median nerve, which innervates that area of the palm, separates from the median nerve and passes over the carpal tunnel.Severe IMNCT is also associated with weakness and atrophy of the muscles at the base of the thumb. People may lose the ability to palmarly abduct the thumb. IMNCT can be detected on examination using one of several maneuvers to provoke paresthesia (a sensation of tingling or "pins and needles" in the median nerve distribution). These so-called provocative signs include:

Phalens maneuver. Performed by fully flexing the wrist, then holding this position and awaiting symptoms. A positive test is one that results in paresthesia in the median nerve distribution within sixty seconds. Tinels sign is performed by lightly tapping the median nerve just proximal to flexor retinaculum to elicit paresthesia. Durkan test, carpal compression test, or applying firm pressure to the palm over the nerve for up to 30 seconds to elicit paresthesia. Hand elevation test The hand elevation test is performed by lifting both hands above the head.
The FDA normally requires at least two positive short-term efficacy studies for approval of antidepressants, but this requirement was loosened for esketamine and a relapse-prevention trial was allowed to fill the place of the second efficacy trial instead. This is the first time that the FDA is known to have made such an exception and the decision has been criticized as lowering regulatory standards. In the relapse-prevention trial (SUSTAIN-2), the rate of depression relapse was significantly lower with esketamine continued than with it discontinued and replaced with placebo in esketamine-treated stable responders and remitters (51% rate reduction in remitters and 70% reduction in responders). Esketamine was approved for the treatment of MDD with co-occurring suicidal ideation or behavior on the basis of two short-term (4-week) phase 3 trials (ASPIRE-1 and -2) of esketamine nasal spray added to a conventional antidepressant. The primary efficacy measure was reduction in MADRS total score after 24 hours following the first dose of esketamine. In both trials, MADRS scores were significantly reduced with esketamine relative to placebo at 24 hours. The mean MADRS scores at baseline were 39.4 to 41.3 in all groups and the MADRS reductions at 24 hours were –15.9 and –16.0 with esketamine and –12.0 and –12.2 with placebo, resulting in mean differences between esketamine and placebo of –3.8 and –3.9. The secondary efficacy measure in the trials was change in Clinical Global Impression of Suicidal Severity - Revised (CGI-SS-r) 24 hours after the first dose of esketamine.