Nitrous oxide-induced myelopathy with inverted V-sign on spinal MRI

A previously healthy 28-year-old male presented with a seven-day history of progressive weakness, numbness and paraesthesias, which initially began in the upper extremities, and subsequently spread to the lower extremities. These symptoms were accompanied by Lhermitte's sign, sexual dysfunction and constipation. Social history was significant for recreational nitrous oxide abuse, characterised by the inhalation of …