| ObjectiveTo investigate the method of MR perfusion of lumbar spine vertebral bone marrow in rabbit,and its acute-stage microcirculation changing after radiotherapy with MR-PWI.MethodsFifteen rabbit(divided in 3 group)underwent dynamic contrast material-enhanced magnetic resonance(MR)imaging of the lumbar spine.24 hours after the the first MR examination,each rabbit underwent radiotherapy on lumbar spine by different X-ray dose(group 1:500cGy,group2:1000 cGy,group3:1500 cGy).Seven days after the Radiotherapy,each subject reunderwent dynamic contrast material-enhanced MRI of the lumbar spine.Serniquantitative(Maximum relative enhancement rate,MRER and wash-in rate)and quantitative(Maximum enhancement value,MEV)parameters were analyzed with the time-intensity curve.Data obtained before and after radiotherapy were compared.The paired-samples T test were used by SPSS12.0.ResultsGroup1:MEV of vertebral bodies ascended from 284.22(mean±SD,284.22±60.82)to 369.62(mean±SD,369.62±80.59)after radiotherapy.Mean ascend was 85.40±79.81,and the percentage difference was 30%(t= 5.242,P=.000).A P value of less than 0.05 was considered to indicate a statistically significant difference.MRER changed from 52.29%(mean,52.29±13.33%)to 57.13%(mean,57.13±11.17%). Mean changes was 4.84±15.87%,and the percentage difference was 9%(t=1.493,P =0.149).A P value of more than 0.05 was considered to showed no differences between before and after radiotherapy,wash-in rate changed from 81.50(mean,81.50±19.98)to 86.91(mean,86.91±18.78).Mean change was 5.41±31.99,and the percentage difference was 7%(t=0.828,P=0.416).A P value of more than 0.05 was considered to showed no differences between before and after radiotherapy.Group2:MEV of vertebral bodies ascended from 273.18(mean±SD,273.18±50.16)to 329.87(mean±SD,329.87±90.92)after radiotherapy.Mean ascend was 56.69±128.24,and the percentage difference was 21%(t=2.166,P = 0.041).A P value of less than 0.05 was considered to indicate a statistically significant difference.MRER decreased from 62.74%(mean,62.74±21.71%)to 58.25%(mean,58.25±12.82%). Mean decrease was 4.49±23.55%,and the percentage difference was 7%(t=0.934,P =0.360).A P value of more than 0.05 was considered to showed no differences between before and after radiotherapy,wash-in rate ascended from 90.79(mean,90.79±20.30)to 107.01(mean,107.01±33.32).Mean ascend was 16.22±37.91,and the percentage difference was 18%,t=2.096(P=0.047).Group3:MEV of vertebral bodies ascended from 226.11(mean±SD,226.11±50.65)to 275.22(mean±SD,275.22±35.71)after radiotherapy.Mean ascend was 49.11±72.48,and the percentage difference was 22%(t=3.319,P=0.003).A P value of less than 0.05 was considered to indicate a statistically significant difference.MRER ascended from 43.78%(mean,43.78±7.45%)to 51.71%(mean,51.71±9.50%). Mean ascend was 7.93±12.01%,and the percentage difference was 18%(t=3.236,P =0.004).A P value of less than 0.05 was considered to indicate a statistically significant difference,wash-in rate ascended from 87.87(mean,87.87±26.30)to 114.87(mean,114.87+39.04).Mean ascend was 27.00±48.84,and the percentage difference was 31%(t=2.709,P=0.013).A P value of less than 0.05 was considered to indicate a statistically significant difference.The outcome shows group 1 before and after radiotherapy only MEV indicate a statistically significant difference.Group2 before and after radiotherapy MEV and wash-in rate indicate statistically significant difference.Group3 before and after radiotherapy all of the three parameters indicate statistically significant difference.So we can guess radiotherapy X-ray dose ascend,the degree of the acute change of the microcirculation of rabbit lumbar spine vertebral bone marrow ascend.Conclusions1.It is feasible that the animal empirical study of lumbar spine vertebral bone marrow by MRPWI.2.After radiotherapy,the acute change of the microcirculation of rabbit lumbar spine vertebral bone marrow is ascended,and the more radiotherapy dosage,the more significant change.
|
PDF Full Text Request