In 2366, Patahk underwent a covert mission into Federation space on the scout ship Pi. The ship crashed on the planet Galorndon Core and his crew mate, Centurion Bochra, apparently activated their ship's self-destruct sequence soon after and separated.
When an away team from the USS Enterprise-D investigated the crash, Lieutenant Worf discovered Patahk and he was beamed up to the Enterprise. Doctor Beverly Crusher attempted to treat Patahk's injuries; however, she found surgery on Romulans to be more difficult than anticipated, having worked with the assumption that it would be the same as working on a Vulcan. She discovered that because of his exposure to radiation and magnetic fields on the surface of Galorndon Core, his brain waves indicated early neural pathway degeneration. She also discovered that he had cell damage to several vital areas and would require a ribosome infusion. Dr. Crusher discovered that the only compatible match aboard the Enterprise-D was with Worf. Worf refused to donate his cells to a Romulan, and Patahk refused to accept cells which he considered "Klingon filth". Patahk later died from his injuries. (TNG: "The Enemy")
Later that year, following the defection of Admiral Alidar Jarok, his alias Sublieutenant Setal commended Dr. Crusher on his fortune in her knowledge of Romulan medicine. She explained that she "had a chance to gain some experience recently," which Setal immediately recognized as "the incident at Galorndon Core. The two officers." Worf sneered at how Setal was "aware of a great deal for a logistics clerk," before Setal claimed that the event was "common knowledge". (TNG: "The Defector")