Risk factor of radiation pneumonitis: assessment with velocity-encoded cine magnetic resonance imaging of pulmonary artery.
OBJECTIVE
The aim of this study was to investigate whether the pulmonary arterial flow obtained as a function of time from velocity-encoded cine (VEC) magnetic resonance (MR) imaging can be used to predict radiation pneumonitis.


METHODS
Before receiving radical radiotherapy, 19 patients with primary lung cancer and 21 with primary esophageal cancer underwent VEC MR imaging to determine their pulmonary arterial flow. The right and left pulmonary arterial flow profiles were digitized, and from these data, acceleration time, maximal change in flow rate during ejection, acceleration volume, and the ratio of maximal change in flow rate during ejection to acceleration volume were measured. The statistical significance of differences in pulmonary arterial flows before irradiation between patients who developed and did not develop RP greater than grade 1 was determined.


RESULTS
Radiation pneumonitis occurred in 5 patients with lung cancer and in 4 with esophageal cancer. The acceleration time (P < 0.001), acceleration volume (P < 0.02), and ratio of the maximal change in flow rate during ejection to acceleration volume (P < 0.002) in patients with and without RP were significantly different. The sensitivity, specificity, and accuracy of using 111 milliseconds as the cutoff value (which was the mean acceleration time in the RP group) to predict RP were 58%, 88%, and 83%, respectively.


CONCLUSIONS
Pulmonary hypertension detected by VEC MR imaging can be a risk factor for development of RP in candidates for pulmonary irradiation.
Murayama
Sadayuki
S
Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Okinawa, Japan. sadayuki@med.u-ryukyu.ac.jp
Muryama
Sadayuki
S
Akamine
Tamaki
T
Sakai
Shuji
S
Oshiro
Yasuji
Y
Kakinohana
Yasumasa
Y
Soeda
Hiroyasu
H
Toita
Takafumi
T
Adachi
Genki
G
D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D004938:Esophageal Neoplasms / Q000532:radiotherapy; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000532:radiotherapy; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000503:physiopathology; D011652:Pulmonary Circulation; D017564:Radiation Pneumonitis / Q000209:etiology* / Q000503:physiopathology; D012307:Risk Factors