MR imaging in comatose survivors of cardiac resuscitation

BACKGROUND AND PURPOSE: The prognosis of comatose survivors is determined b y clinical examination. Early laboratory indicators of poor prognosis (such as evoked potentials) have low sensitivity. The role of MR imaging as a co nfirmatory study was investigated. METHODS: We studied fluid-attenuated inversion recovery (FLAIR) and diffusi on-weighted (DW) imaging in 10 patients comatose after cardiac arrest. RESULTS: None of the 10 comatose patients had myoclonus status epilepticus or fixed, dilated pupils on neurologic examination, and none had abnormal s omatosensory-evoked potentials. Eight patients showed diffuse signal abnorm alities, predominantly in the cerebellum (n = 5), the thalamus (n = 8), the frontal and parietal cortices (n = 8), and the hippocampus (n = 9). One pa tient showed normal MR imaging results, and one patient had abnormalities i n the thalamus and cerebellum and minimal abnormality on DW images; both la ter awakened. None of the patients with abnormal cortical structures on FLA IR MR images recovered beyond a severely disabled state. CONCLUSION. MR imaging in comatose survivors may parallel the pathologic fi ndings in severe anoxic-ischemic injury, and extensive abnormalities may in dicate little to no prospects for recovery. If confirmed, MR imaging may ha ve a role as a prognosticating test in anoxicischemic coma.