ISSN:
1432-1084
Keywords:
Key words: MR imaging
;
Radiation myelitis
;
Over-irradiation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract. The objective of this work is to report the MRI findings in patients with radiation myelopathy due to accidental local over-irradiation syndrome. Eight patients (seven males and one female) were suffering from over-irradiation syndrome as a result of treatments from a malfunctioning linear electron accelerator. The mean accidental estimated dose was 136 Gy delivered to the “open-neck” (seven cases) and to the thoracic wall (one case), during a mean of 5.4 sessions (range 1–9 sessions). Paresthesia and weakness in the upper extremities were the earliest symptoms (87.5 %), with evolution to paralysis in all patients. No patient is alive (mean survival time 64 days). In all cases MRI was negative for neurologic lesions in the acute phase ( 〈 90 days from irradiation; Radiation Therapy Oncology Group scoring system). Late signs of radiation myelitis manifested as high-intensity signals on T2-weighted images in three patients, and as Gd-DTPA enhancement of T1-weighted images in one case. Autopsies performed on four patients who died in acute phase showed morphologic alterations in white matter: edema in 75 %, and necrosis and glial reaction as well as obliterative vasculitis in all cases. In cases of over-irradiation, MRI may be normal in acute phase even if the patients have severe neurologic deficit, as positive MRI findings appear only in delayed radiation myelitis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s003300050174
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