CAJ | 학술논문

目的研究脑转移瘤全脑放疗中血脑屏障变化规律,为全脑放疗过程中化疗的介入时机提供影像学依据.方法对接受6MVX射线全脑外照射的20例脑转移瘤患者,在放射治疗前、放射治疗20 Gy、40 Gy及放射治疗结束后2周采用~(99)mTc-DTPA核素进行脑断层显像,选择一帧显示肿瘤最好的横断层像,于肿瘤区(T)、对侧正常脑组织区(N)以及颅骨周围软组织外本底区(B)设置相同的感兴趣区,采集各区的放射性计数,分别计算放疗前、放疗20 Gy、40 Gy及放疗结束后2周时病灶、受到照射的正常脑组织部位的计数与本底区域计数的比值.结果放疗前20例患者其30个脑转移瘤的比值T/B和N/B分别为(142.2±51.1),(82.6±42.3);放疗20 Gy时其比值分别为(260.3±121.5),(150.7±72.5);放疗40 Gy时其比值分别为(251.6±118.3),(161.8±68.4);放疗结束后2周其比值分别为(250.3±117.2),(158.6±73.5).20 Gy组、40 Gy组及放疗结束后2周组分别与放疗前组比较差异均有统计学意义(P<0.05),但20 Gy组、40 Gy组及放疗结束后2周组两两比较差异无统计学意义(P>0.05).结论放射线具有降低血脑屏障功能的作用,照射20～40 Gy及放疗结束后2周内其通透性明显增加,故20～40 Gy及放疗结束后2周内均可成为化疗介入时机.
목적 연구뇌전이류전뇌방료중혈뇌병장변화규률,위전뇌방료과정중화료적개입시궤제공영상학의거.방법 대접수6MVX사선전뇌외조사적20례뇌전이류환자,재방사치료전、방사치료20 Gy、40 Gy급방사치료결속후2주채용~(99)mTc-DTPA핵소진행뇌단층현상,선택일정현시종류최호적횡단층상,우종류구(T)、대측정상뇌조직구(N)이급로골주위연조직외본저구(B)설치상동적감흥취구,채집각구적방사성계수,분별계산방료전、방료20 Gy、40 Gy급방료결속후2주시병조、수도조사적정상뇌조직부위적계수여본저구역계수적비치.결과 방료전20례환자기30개뇌전이류적비치T/B화N/B분별위(142.2±51.1),(82.6±42.3);방료20 Gy시기비치분별위(260.3±121.5),(150.7±72.5);방료40 Gy시기비치분별위(251.6±118.3),(161.8±68.4);방료결속후2주기비치분별위(250.3±117.2),(158.6±73.5).20 Gy조、40 Gy조급방료결속후2주조분별여방료전조비교차이균유통계학의의(P<0.05),단20 Gy조、40 Gy조급방료결속후2주조량량비교차이무통계학의의(P>0.05).결론방사선구유강저혈뇌병장공능적작용,조사20～40 Gy급방료결속후2주내기통투성명현증가,고20～40 Gy급방료결속후2주내균가성위화료개입시궤.
Objective To study the pattern of blood-brain barrier (BBB) permeability changes during whole brain radiotherapy (WBRT) for metastatic brain tumor. Methods Twenty patients with metastatic brain tumors receiving WBRT by 6 MV X-ray underwent ~(99)mTc-DTPA brain SPECT before and during WBRT (20, 40 Gy) and at 2 weeks after the end of irradiation. A frame of transverse ~(99)mTc-DTPA brain SPECT image that best displayed the brain metastasis was chosen, and the regions of interest (ROD were defined in the tumor foci (T), the contralateral normal brain tissue (N) and the background outside the soft tissues around the cranium (B). The radioactive counts of every ROI were measured and the ratios of the total counts (T/B and N/B) before and during WBRT (20 Gy, 40 Gy) and at 2 weeks after the irradiation were calculated. Results The average T/B and N/B in the 20 patients with 30 brain metastases was 142.2±51.1 and 82.6±42.3 before WBRT, 260.3±121.5 and 150.7± 72.5 during 20 Gy WBRT, 251.6±118.3 and 161.8±68.4 during 40 Gy WBRT, and 250.3±117,2 and 158.6±73.5 at 2 weeks after the irradiation, respectively. The measurements during WBRT (20 and 40 Gy) and at 2 weeks after the irradiation group underwent no significant variations (P>0.05), but showed significant differences from those before WBRT (P<0.05).Conclusion kradiation causes direct damage of the BBB function, and the permeability of the BBB increases significantly during and within 2 weeks following 20 and 40 Gy WBRT, which provides the optimal time window for interventions with chemotherapy.