时间、剂量、分割对鼻咽癌放疗后颞叶坏死的影响

研究不同放射因素与NPC放疗后颞叶坏死(TLN)的相关性及不同的生物相等效模式对判断预后的准确性,作者对1976～1985年连续1008例采用不同分割方案进行根治性放疗的T_1期NPC病例进行分析。男:女=2.1:1,年龄18～84岁(平均46岁)。92％的病人完全随访,平均随访6.9年(0.1～17.5年),856例(85％)随访2年以上。病人特征为:①T_1期鳞癌,无远处转移证据,单纯放射治疗。②用4.5～6MV光子,标准3野照射,射野包括亚临床灶,咽后间隙第1站淋巴结。治疗野上缘在前床突上5mm。③给予根治剂量,肿瘤在100％等剂量水平(误     

鼻咽癌放疗后放射性颞叶坏死患者的脑血管动脉硬化的临床研究

目的 探讨鼻咽癌患者放射性颈动脉损伤和脑血管损伤的临床特点及其与放射性颞叶坏死的关系。方法 回顾性分析本院58例鼻咽癌放射性颞叶坏死（temporal lobe necrosis,TLN）的临床资料,采用多普勒超声检查双侧颈动脉内膜中层厚度（intima-media thickness,IMT）和斑块形成情况,应用经颅彩色多普勒（TCD）检测双侧大脑中动脉（MCAs）、颈内动脉（ICAs）和基底动脉（BA）的血流速度,与33例放疗后无TLN的患者和29例健康者的相关结果进行比较,并分析IMT、斑块出现率与各因素的相关性。结果 放射治疗后患者颈内动脉IMT、斑块发生率及MCAs、ICAs的血流速度差异均有统计学意义（t=18.624、8.221,P < 0.05;χ²=17.886,P < 0.05;t=14.367、10.112,P < 0.05）,IMT与放疗后时限呈正相关（r=0.368,P=0.049）,IMT、斑块发生率与放疗剂量、疗程和病理分期可能有一定相关性（χ²=-17.635、12.006、-3.125,P < 0.05）。与无放射性TLN的患者相比,TLN患者平均IMT明显增厚（t=10.208,P < 0.05）。TLN患者的斑块比无TLN者更常见（χ²=13.118,P < 0.05）,ICAs和MCAs的血流速度较快（t=5.011、5.035,P < 0.05）。在单侧TLN患者中,患侧与健侧的MCAs血流速度明显不同（t=18.362,P < 0.05）。结论 与健康者比较,鼻咽癌放疗后患者的IMT增厚、斑块形成和血流动力学异常较常见,特别是合并TLN者。     

鼻咽癌调强放疗对海马结构的剂量影响分析

目的 分析鼻咽癌调强放疗中海马结构的受照剂量及相关影响因素.方法 回顾性分析59例鼻咽癌的调强放疗计划,比较不同临床分期鼻咽癌的海马结构受照剂量及特点.结果 59例鼻咽癌患者的海马结构受照剂量受T分期影响明显,Dmax11.1 ～78.2 Gy,Dmean3.2 ～44.6 Gy,T1 ～T4期海马结构受照剂量(Dmax和Dmean)差异均有统计学意义,Dmax(F=24.2,P＜0.05)、Dmean(P=16.3,P＜0.05).其中T3、T4期病例平均受照剂量和体积明显高于T1、T2期,Dmax、Dmean分别为(58.6±14.8)Gy、(20.9±19.3) Gy和(40.8±9.4) Gy、(12.5±5.1) Gy.结论 鼻咽癌调强放疗中,海马结构可能受到较大剂量的照射,肿瘤T分期是重要的影响因素,特别在T3-4期病例放疗中值得关注.     

不同分割剂量对骨转移瘤放疗止痛疗效观察

恶性肿瘤骨转移所致的疼痛是癌痛的重要原因之一,它直接影响患的生存质量和生存期,骨转移的放疗止痛作用既快又好,多数骨转移瘤需放疗止痛。我科自1990年1月至1998年1月对64例,94个病灶,根据患的不同情况采用不同分割剂量放疗,并作了对比观察,报告如下。     

MRS定量分析鼻咽癌放疗后靶区颞叶代谢的研究

目的 探讨氢质子磁共振波谱技术(1HMRS)对鼻咽癌(NPC)放射性脑损伤的诊断价值,通过线性拟合模型(LCModel)绝对值定量鼻咽癌放疗后颞叶细胞代谢变化规律,推测细胞代谢变化的可能机制.方法 1HMRS扫描59例NPC放疗患者颞叶照射野和24例对照组健康志愿者颢叶,获取波谱图像并计算N-乙酰天冬门氨酸(NAA)/胆碱(Cho)、Cho/肌酸(Cr)值,LCModel定量NAA、Cho和Cr值,并进行统计学分析.按放疗后行1 HMRS检查的时间将患者和对照组健康志愿者分为4组:组1(放疗结束1周内,n=16),组2(放疗后1周～6个月,n=22),组3(放疗后6～1 2个月,n=21),组4(对照组,n=24).所有试验组及对照组成员常规磁共振图像均无异常影像学改变.结果 放疗结束1周内(组1)3项绝对值均最低并低于对照组,其中NAA绝对值、Cho绝对值和其余2组试验组分别具有统计学意义,Cr绝对值和对照组之间无统计学意义(0.05＜P＜0.10);放疗结束后1周～6个月的Cho绝对值最高,与对照组P值＜0.05.放疗结束后1周内NAA/Cr值最低,与对照组之间无统计学意义;放疗结束后1周～6个月Cho/Cr值最高且和其余3组均有统计学意义.结论 1HMRS能监测NPC放射性脑损伤的细胞代谢物浓度变化,LCModel定量的绝对值较传统比值更早发现NPC放射性脑损伤细胞代谢变化,提供放射性脑损伤的影像学诊断依据.     

鼻咽癌后程三维适形放疗与常规分割放疗的临床研究

目的探讨后程三维适形放疗（3D—CRT）与常规分割放疗（cv）治疗鼻咽癌的疗效和毒副反应。方法将符合入组条件的62例鼻咽鳞癌患者随机分为CF组和3D—CRT组各31例。两组均采用双侧面颈联合野对穿照射,200cGy／次,5次,周,鼻咽部剂量达36～40Gy后改为小面颈野或耳前野对穿避开脊髓继续照射;CF组继续用原分割方案照射至鼻咽部总量66—70Gy,3D—CRT组照射50Gy后改用三维适形放射治疗,3．5～4Gy／次,4次／周,连续5-6次,总剂量达76～81Gy。颈部淋巴结转移灶照射到68—70Gv,预防照射50Gy。结果3D—CItT组及CF组3、5年原发灶控制率分别为94％、74％和81％、48％（χ2=4．94,P=0．029）;生存率分别为90％、77％和81％、52％（χ2=4．80,P=0．032）。两组急性毒副反应及放射后遗症发生率差异无显著性（χ2=0．34、0．08,P=0．577、0．778）。结论后程三维适形放疗与常规分割放疗相比,提高了鼻咽癌3、5年局部控制率及生存率．而未增加急性毒性反应和放疗后遗症。     

鼻咽癌调强放疗中实施同一计划对剂量的影响

目的 探讨鼻咽癌调强放疗过程中实施同一治疗计划的可行性。方法 选10例采用调强放射治疗的鼻咽癌患者,用Pinnacle³制定IMRT计划。在患者放疗中期重新行CT定位扫描,把基于初次定位CT图像所做的IMRT计划复制到重新定位CT图像上,使得照射野参数保持一致,测得基于两套图像计划中的肿瘤靶区、脊髓、脑干和腮腺的受量。统计在整个放疗过程中如果实施同一计划,患者靶区及各器官的剂量变化率。结果 两组计划相比,等中心层面外轮廓左右和前后长度平均缩小8%、3%。靶区PTV₁(D₉₅)减少0.6%~5.3%;放疗中期和放疗前相比右侧和左侧腮腺体积分别缩小13.1%~41.4%、12.0%~49.0%;右侧和左侧腮腺平均剂量增加5.6%~45.1%、3.3%~32.2%;脊髓最大剂量变化为-4.1%~13.9%;脑干剂量变化为-3.9%~9.3%。结论 对于采用鼻咽癌调强放射治疗的患者,在不考虑摆位误差的影响因素下,由于靶区及正常组织显著变化等因素影响有重新定位修改计划的必要性。     

螺旋断层放疗提升鼻咽癌放疗剂量的可行性研究

目的 探讨应用螺旋断层放疗(HT)进行鼻咽癌放疗处方剂量提升的可行性及剂量学特点。方法 选取10例9野静态调强放疗的鼻咽癌计划,制定HT计划和静态调强(sIMRT)计划。在危及器官(OAR)符合正常组织临床影响量化分析标准的前提下,提升两组计划处方剂量,并比较剂量提升空间及处方剂量提升后两者的剂量学差异。结果 与sIMRT计划相比,HT计划所达到的处方剂量比sIMRT计划增加了42.6%(t=6.373,P<0.01);处方剂量提升后,HT计划的均匀性指数仍优于sIMRT计划(t=-2.288,P<0.05),但适形度指数略低于sIMRT计划(P>0.05)。限制HT计划处方剂量提升的OAR为脊髓(2例)、视神经(5例)、脑干(3例);限制sIMRT计划处方剂量提升的OAR为眼晶状体(1例)、脊髓(1例)、腮腺(8例)。结论 HT的高束流调强能力,使其在有效保护OAR的前提下,能够提高鼻咽癌放疗处方剂量。在sIMRT实现高处方剂量要求存在困难时,可考虑使用HT进行放疗。     

鼻咽癌常规和超分割后加速放疗的疗效分析

目的 比较鼻咽癌常规和超分割后加速放疗的局部控制率和生存率。 方法 200例初治鼻咽癌患者根据计算机产生的随机数入常规组和超分割后加速放疗组,鼻咽原发灶采用⁶⁰Co γ射线或6 MV X射线外照射,常规组70 Gy/35次/7周,超分割后加速放疗组前4周采用超分割1.2 Gy/次,剂量为48 Gy/40次,后2周加速超分割1.5 Gy/次,剂量为30 Gy/20次,均为2次/d,间隔≥6 h,5 d/周。结果 常规组99例中,远处转移25例、鼻咽复发25例、颈部复发16例;超分割后加速放疗组101例中,远处转移18例、鼻咽复发16例、颈部复发13例。常规组和超分割后加速组5年鼻咽局部控制率分别为75.9%、87.6% (χ²=4.066, P<0.05),总生存率分别为58.0%、74.1%(χ²=5.076, P<0.05),5年无远处转移率分别为74.1%、83.3%(P> 0.05),颈部局部控制率分别为81.5%、90.0%(P> 0.05)。结论 与常规分割相比,超分割后加速放疗组提高了鼻咽局部控制率和总生存率,未减少颈部复发和远处转移率。     

脑放射性坏死的发病率和危险性与剂量、时间、分割和体积的关系

有关原发性脑肿瘤,垂体瘤,脑以外肿瘤放疗后脑坏死的报道屡见不鲜。但脑坏死与放射的剂量、时间、分割、体积之间的关系仍不清楚。许多学者对此进行过探讨,均因方法不当未能成功。本文的目的在于阐明脑放射性坏死的发生率和脑坏死与放射的剂量,时间、分割、体积之间的关系。作者研究了1974至1976年的152例原发性脑肿瘤和垂体瘤放疗后病人。其中131例>15岁,余均为儿童。139例剂量为4500rad或更多,每次180～200rad。139例当中有7例经放射治疗后发生了为组织学所证实的脑放射性坏死。该7例病人的中位生存期为14个月。脑坏死的组织学来源有4例来自尸检,2例来自再次手术,1例来自穿刺活检,有3例脑坏死灶远离肿瘤,2例靠近肿瘤,2例在瘤床内。     

食管癌的放疗:总时间与分割的影响

1979年～1992年作者对88例资料完整的Ⅰ～Ⅲ期,总量>55Gy的食管癌作了根治性放疗(RT),重点评价总时间与分割对局控与生存率的影响。按照分割的不同分两组:A组:常规分割,每天一次,5次/周,1.8～2Gy/次,前后对穿野,上下界超出肿瘤缘至少3cm,宽6～8cm,总量50～70Gy,平均64Gy,其中10～20Gy用旋转或楔形法给予,以免脊髓超量。B组:加速超分割(AHF),始于1989年5月后,一天照2次。用两种不同方案;①15例用Bid同时     

乳腺癌术后胸壁放射治疗剂量分割方案的探讨

乳腺癌是女性最常见恶性肿瘤之一，目前国内仍多采用(改良)根治术为主的综合治疗。其中胸壁放射治疗作为术后放疗的一部分，对局控率乃至远期生存率的改善已经多项研究证实。术后胸壁放疗普遍实施常规分割方案(Dr50Gy／25次共5周)，疗效较为稳定。但治疗周期长，医生工作量大，患者经济负担重。因此，在不影响疗效、不增加毒副作用的同时，     

鼻咽癌放疗后颞叶脑放射性损伤的磁共振扩散张量成像的表现

目的 探讨扩散张量成像(diffusion tensor imaging,DTI)在早期放射性脑损伤中的应用价值.方法 23例鼻咽癌放疗后常规MR表现正常者和28例健康正常人均做DTI,在双侧颞叶脑白质区域测量各向同性扩散张量(ADCiso)值和各向异性指数值.结果 鼻咽癌放疗组ADCiso值(644.08±56.80)×10-6mm2/s,部分各向异性(FA)值0.394±0.074、相对各向异性(RA)值0.344±0.075及1减容积比(1-VR)值0.182±0.072均比正常对照组各值降低,与正常对照组比较差异有显著性意义(P<0.05).结论 DTI能探测到鼻咽癌放疗后常规脑MR表现所不能显示的改变,对放射性脑损伤的早期诊断提供了一种新的影像学诊断手段.     

放疗中呼吸运动对不同形状射野剂量分布的影响

Objective To evaluate the influence of respiration on the radiation dose distribution within target volume in radiotherapy with film dosimetry. Methods Radiation of 50 MU was delivered by a square, round, ellipse, dumb bell, or female shaped filed to the films within a moving or motionless Respiration Motion Phantom respectively, the dose distributions for the two motion status were measured and compared. In order to further verify the impact of respiration, a plank phantom was used on different shifting value: 0, 0.5, 1.0, 1.5 and 2.0 cm, respectively. A square, round, or eUipse-shaped filed was used for irradiation and the distributions in different status were measured and compared with film dosimetry. Iso-dose line comparison, NAT(Normalized Agreement Tests) and γ comparison were used for the comparison of dose distributions. Fs can be an index to reflect the variability of the areas that surrounded by iso-dose lines. (FS90, FS50, FS25 delegates the ratio of the areas that surrounded by 90 %,50 %,25 % iso-dose hne in different situation respectively). Results (1) Compared with motionless situation, the FS90 in horizontal movement situation became small and the FS25 became large. As the displacement became larger, the FS90 became larger and the FS25 became smaller. FS in vertical movement situation, square and dumb bell fields changed while the others didn't have a change. (2)γ and NAT comparison: In the horizontal movement situation, compared with the static phantom, Pγ < 60 % and PNAT < 75 %. Under vertical movement situation, Pγ were less than 85 % for the square, round, dumb bell and female shaped fileds. In the plank phantom verification, Pγ and PNAT became smaller as the movement became larger. Conclusions The respiration can impact on the dose distribution within the target volume in radiotherapy, leading to a smaller area of higher dose level and an expanded area of lower dose level. The influence will become more significant with larger movement of the target.     

放疗中呼吸运动对不同形状射野剂量分布的影响

目的 利用剂量胶片分析研究放射治疗中呼吸运动对靶区剂量分布的影响。方法应用可内置胶片的QUASAR多功能呼吸运动体模,在运动和静止状态下分别照射正方形、圆形、椭圆形、哑铃形和凹形5种形状的模拟射野。比较其剂量分布的差别。用平板体模在位移为0、0.5、1.0、1.5和2.0cm时分别照射圆形、椭圆形、正方形射野,比较不同靶区位移大小对剂量分布的影响。应用的比较方法包括等剂量线、γ值和NAT比较法。提出面积变化因子F_s(运动状态下面积/静止状态面积或位移不为0时的面积/位移为0时的面积。以F_S90、F_S50、F_S25分别代表90%、50%、25%剂量曲线包围的面积在不同状态下的比值)。结果 与静态下相比,水平运动状态下的F_S90减小,F_S25增大。位移越大,它们偏离程度越大。垂直运动状态,正方形和哑铃形射野的F_s有变化,其余变化很小。γ值和NAT比较:各射野的水平运动状态和静止状态比较,P_γ＜60%和P_NAT＜75%;正方形、圆形、凹形和哑铃形照射野的垂直运动状态与静态下相比,P_γ＜85%;平板体模验证中,P_γ和P_NAT随着位移的增大而减小。结论 呼吸运动对靶区放射治疗的剂量分布的影响表现为沿运动方向高剂量区域内收,低剂量区扩大,这种影响随着肿瘤位移的增大而增大。     

放疗中呼吸运动对不同形状射野剂量分布的影响

Objective To evaluate the influence of respiration on the radiation dose distribution within target volume in radiotherapy with film dosimetry. Methods Radiation of 50 MU was delivered by a square, round, ellipse, dumb bell, or female shaped filed to the films within a moving or motionless Respiration Motion Phantom respectively, the dose distributions for the two motion status were measured and compared. In order to further verify the impact of respiration, a plank phantom was used on different shifting value: 0, 0.5, 1.0, 1.5 and 2.0 cm, respectively. A square, round, or eUipse-shaped filed was used for irradiation and the distributions in different status were measured and compared with film dosimetry. Iso-dose line comparison, NAT(Normalized Agreement Tests) and γ comparison were used for the comparison of dose distributions. Fs can be an index to reflect the variability of the areas that surrounded by iso-dose lines. (FS90, FS50, FS25 delegates the ratio of the areas that surrounded by 90 %,50 %,25 % iso-dose hne in different situation respectively). Results (1) Compared with motionless situation, the FS90 in horizontal movement situation became small and the FS25 became large. As the displacement became larger, the FS90 became larger and the FS25 became smaller. FS in vertical movement situation, square and dumb bell fields changed while the others didn't have a change. (2)γ and NAT comparison: In the horizontal movement situation, compared with the static phantom, Pγ < 60 % and PNAT < 75 %. Under vertical movement situation, Pγ were less than 85 % for the square, round, dumb bell and female shaped fileds. In the plank phantom verification, Pγ and PNAT became smaller as the movement became larger. Conclusions The respiration can impact on the dose distribution within the target volume in radiotherapy, leading to a smaller area of higher dose level and an expanded area of lower dose level. The influence will become more significant with larger movement of the target.     

放疗中呼吸运动对不同形状射野剂量分布的影响

Objective To evaluate the influence of respiration on the radiation dose distribution within target volume in radiotherapy with film dosimetry. Methods Radiation of 50 MU was delivered by a square, round, ellipse, dumb bell, or female shaped filed to the films within a moving or motionless Respiration Motion Phantom respectively, the dose distributions for the two motion status were measured and compared. In order to further verify the impact of respiration, a plank phantom was used on different shifting value: 0, 0.5, 1.0, 1.5 and 2.0 cm, respectively. A square, round, or eUipse-shaped filed was used for irradiation and the distributions in different status were measured and compared with film dosimetry. Iso-dose line comparison, NAT(Normalized Agreement Tests) and γ comparison were used for the comparison of dose distributions. Fs can be an index to reflect the variability of the areas that surrounded by iso-dose lines. (FS90, FS50, FS25 delegates the ratio of the areas that surrounded by 90 %,50 %,25 % iso-dose hne in different situation respectively). Results (1) Compared with motionless situation, the FS90 in horizontal movement situation became small and the FS25 became large. As the displacement became larger, the FS90 became larger and the FS25 became smaller. FS in vertical movement situation, square and dumb bell fields changed while the others didn't have a change. (2)γ and NAT comparison: In the horizontal movement situation, compared with the static phantom, Pγ < 60 % and PNAT < 75 %. Under vertical movement situation, Pγ were less than 85 % for the square, round, dumb bell and female shaped fileds. In the plank phantom verification, Pγ and PNAT became smaller as the movement became larger. Conclusions The respiration can impact on the dose distribution within the target volume in radiotherapy, leading to a smaller area of higher dose level and an expanded area of lower dose level. The influence will become more significant with larger movement of the target.     

放疗中呼吸运动对不同形状射野剂量分布的影响

Objective To evaluate the influence of respiration on the radiation dose distribution within target volume in radiotherapy with film dosimetry. Methods Radiation of 50 MU was delivered by a square, round, ellipse, dumb bell, or female shaped filed to the films within a moving or motionless Respiration Motion Phantom respectively, the dose distributions for the two motion status were measured and compared. In order to further verify the impact of respiration, a plank phantom was used on different shifting value: 0, 0.5, 1.0, 1.5 and 2.0 cm, respectively. A square, round, or eUipse-shaped filed was used for irradiation and the distributions in different status were measured and compared with film dosimetry. Iso-dose line comparison, NAT(Normalized Agreement Tests) and γ comparison were used for the comparison of dose distributions. Fs can be an index to reflect the variability of the areas that surrounded by iso-dose lines. (FS90, FS50, FS25 delegates the ratio of the areas that surrounded by 90 %,50 %,25 % iso-dose hne in different situation respectively). Results (1) Compared with motionless situation, the FS90 in horizontal movement situation became small and the FS25 became large. As the displacement became larger, the FS90 became larger and the FS25 became smaller. FS in vertical movement situation, square and dumb bell fields changed while the others didn't have a change. (2)γ and NAT comparison: In the horizontal movement situation, compared with the static phantom, Pγ < 60 % and PNAT < 75 %. Under vertical movement situation, Pγ were less than 85 % for the square, round, dumb bell and female shaped fileds. In the plank phantom verification, Pγ and PNAT became smaller as the movement became larger. Conclusions The respiration can impact on the dose distribution within the target volume in radiotherapy, leading to a smaller area of higher dose level and an expanded area of lower dose level. The influence will become more significant with larger movement of the target.     

放疗中呼吸运动对不同形状射野剂量分布的影响

Objective To evaluate the influence of respiration on the radiation dose distribution within target volume in radiotherapy with film dosimetry. Methods Radiation of 50 MU was delivered by a square, round, ellipse, dumb bell, or female shaped filed to the films within a moving or motionless Respiration Motion Phantom respectively, the dose distributions for the two motion status were measured and compared. In order to further verify the impact of respiration, a plank phantom was used on different shifting value: 0, 0.5, 1.0, 1.5 and 2.0 cm, respectively. A square, round, or eUipse-shaped filed was used for irradiation and the distributions in different status were measured and compared with film dosimetry. Iso-dose line comparison, NAT(Normalized Agreement Tests) and γ comparison were used for the comparison of dose distributions. Fs can be an index to reflect the variability of the areas that surrounded by iso-dose lines. (FS90, FS50, FS25 delegates the ratio of the areas that surrounded by 90 %,50 %,25 % iso-dose hne in different situation respectively). Results (1) Compared with motionless situation, the FS90 in horizontal movement situation became small and the FS25 became large. As the displacement became larger, the FS90 became larger and the FS25 became smaller. FS in vertical movement situation, square and dumb bell fields changed while the others didn't have a change. (2)γ and NAT comparison: In the horizontal movement situation, compared with the static phantom, Pγ < 60 % and PNAT < 75 %. Under vertical movement situation, Pγ were less than 85 % for the square, round, dumb bell and female shaped fileds. In the plank phantom verification, Pγ and PNAT became smaller as the movement became larger. Conclusions The respiration can impact on the dose distribution within the target volume in radiotherapy, leading to a smaller area of higher dose level and an expanded area of lower dose level. The influence will become more significant with larger movement of the target.