Radiation induced myelopathy: a retrospective analysis with respect to the factors affecting

Radiation-induced myelopathy is a chronic handicap, though usually reversible in mild forms but is frightening because it could be severe, progressive and irreversible. It usually starts appearing several months to years after radiotherapy. We collected data for 150 patients treated (66 Gy/33Fr; 2 Gy/Fr; 5 Fr/week) between june 2013 to dec 2013, with respect to radiation dose delivered to the spinal cord in head and neck cases. Different types of data were collected including max dose received by spinal cord, spinal cord length being irradiated, the volume of spinal cord receiving more than or equal to 45 Gy. The patients were followed and history for post RT neuritic symptoms was taken. In our study, 2% of patients who received ≥50 Gy dose showed some early and mild symptoms of myelopathy such as Lhermitte sign, tingling or burning sensation in limbs,The appearance of symptoms was strongly associated with the maximum dose received >50Gy (p<0.01), volume of spinal cord receiving ≥45 Gy (p<0.01) also the length of the spinal behind the field opened by secondary collimators (<20cm vs >20cm; p<0.01), females were affected slightly more than males but the difference wasn't statistically significant(p>0.05). Myelopathy is a rare but serious complication of radiation therapy (RT). Radiation myelopathy is white matter damage to the spinal cord developed after a certain period of application of ionizing radiation. The latency of symptoms being 6-24 months. Not just the maximum dose but other factors also influence the chances of appearance of myelopathy symptoms. (author)