Myelitis is a severe neurological complication associated with Mycoplasma pneumoniae infections. Little is known about the extent and the reversibility of this myelitis, and reports on the value of spinal imaging are inconclusive. To obtain more information on the diagnostic and prognostic value of spinal magnetic resonance imaging (MRI) we studied the clinical course and MRI long-term follow-up of two patients with extensive myelitis associated with M. pneumoniae infection. The neuroradiological findings were correlated with the clinical extent of the spinal syndrome, but their reversibility preceded clinical improvement. These preliminary findings indicate that follow-up spinal MRI may give valuable prognostic information in cases of M. pneumoniae associated myelitis and warrant further more systematic studies to ascertain the relationship between spinal MRI findings and prognosis.