Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment

The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery.

Assessment of cerebrovascular reserve impairment using the breath-holding index in patients with leukoaraiosis

Many studies have demonstrated that leukoaraiosis is associated with impaired cerebrovascular reserve function. However, the definitive hemodynamic changes that occur in leukoaraiosis are not clear, and there are many controversies. This study aimed to investigate hemodynamic changes in symptomatic leukoaraiosis using transcranial Doppler ultrasonography and the breath-holding test in a Chinese Han population, from northern China. A total of 203 patients who were diagnosed with ischemic stroke or clinical chronic progressive ischemic symptoms were enrolled in this study, including 97 males and 106 females, with an age range of 43-93 years. The severity of leukoaraiosis was evaluated according to the Fazekas grading scale, and patients were divided into four groups accordingly. Grade 0 was no leukoaraiosis, and grades I, II, and III were mild, moderate, and severe leukoaraiosis, respectively, with 44, 79, 44, and 36 cases in each group. Transcranial Doppler ultrasonography and the breath-holding test were performed. The mean blood flow velocity of the bilateral middle cerebral artery was measured and the breath-holding index was calculated. The breath holding index was correlated with leukoaraiosis severity and cognitive impairment. Patients with a low breath holding index presented poor performance in the Montreal Cognitive Assessment (MoCA) and executive function tests. That is, the lower the breath holding index, the lower the scores for the MoCA and the higher for the trail-making test Parts A and B. These results indicate that the breath-holding index is a useful parameter for the evaluation of cerebrovascular reserve impairment in patients with leukoaraiosis. In addition, the breath-holding index can reflect cognitive dysfunction, providing a new insight into the pathophysiology of leukoaraiosis. This study was approved by the Ethics Committee of the Fifth Peoples Hospital of Shenyang, China (approval No. 20160301) and registered in the Chinese Clinical Trial Registry (registration number: ChiCTR1800014421).

Benefits of Radiotherapy with Indigenous Tools Aiding Deep Inspiration Breath Holding Technique Compared to Free Breathing Technique among Breast Cancer Patients in Bangladesh

Background: Post-operative breast radiotherapy is used to reduce recurrence. The aim of this study was to investigate the outcomes of Deep Inspiration Breath-Hold (DIBH) technique with indigenous breath holding indicator scale in 3DCRT for breast cancer radiotherapy over Free Breathing (FB) technique. Methods: An observational study conducted at the Department of Radiation Oncology at National Institute of Cancer Research and Hospital, Dhaka and Square Hospital Limited, Dhaka, Bangladesh from June 2015 to May 2016. A total of 60 confirmed breast cancer patients who underwent adjuvant radiotherapy were included. An indigenous reproducible plastic tool (Perspex) was used as breath holding indicator scale with DIBH technique in 3DCRT. Paired sample t-test was used to compare with FB technique. Results: The mean age of patients was 47.32 (SD ± 8.33) years. In FB technique, Mean Heart Dose (MHD) was 413.27 cGy while in DIBH technique, it was 254.91 cGy (P < 0.001). The mean heart V20 and V30 were 5.5%, 4.37% in FB and 3.13%, 2.36% in DIBH respectively. In FB technique LADMD, LAD 0.2 cm3, ILMD and ILV20 were 1698.17 cGy, 2852.53 cGy, 1155.31 cGy and 28.62% while in DIBH technique, it was reduced to 1164.01 cGy, 2132.24 cGy, 1007.98 cGy and 23.39% respectively. Similarly, the lung-CLMD and breast-CLMD were reduced from 38.37 cGy and 55.18 cGy to 24.64 cGy and 33.82 cGy respectively (P < 0.001). The mean difference for breast-CLMD was 21.36 cGy. Conclusion: The use of indigenous breath holding indicator scale with DIBH had better outcomes on breast cancer radiotherapy.

Lesion discrimination with breath-hold hepatic diffusionweighted imaging:A meta-analysis

AIM:To investigate the diagnostic capability of breathhold diffusion-weighted imaging(DWI) for differentiation between malignant and benign hepatic lesions.METHODS:A total of 614 malignant liver lesions(132 hepatocellular carcinomas,468 metastases and 14 intrahepatic cholangiocarcinomas) and 291 benign liver lesions(102 hemangiomas,158 cysts,24 focal nodular hyperplasia,1 angiomyolipoma and 6 hepatic adenomas) were included from seven studies(eight sets of data).RESULTS:The pooled sensitivity and specificity of breath-hold DWI were 0.93 [95% confidence interval(CI):0.91-0.95] and 0.87(95%CI:0.83-0.91),respectively.The positive likelihood ratio and negative likelihood ratio were 7.28(95%CI:4.51-11.76) and 0.09(95%CI:0.05-0.17),respectively.The P value for χ2 heterogeneity for all pooled estimates was < 0.05.From the fitted summary receiver operating characteristic curve,the area under the curve and Q * index were 0.96 and 0.91,respectively.Publication bias was not present(t = 0.49,P = 0.64).The meta-regression analysis indicated that evaluated covariates including magnetic resonance imaging modality,echo time,mean age,maximum b factor,and number of b factors were not sources of heterogeneity(all P > 0.05).CONCLUSION:Breath-hold DWI is useful for differentiating between malignant and benign hepatic lesions.The diffusion characteristics of benign lesions that mimic malignant ones have rarely been investigated.

Comparisons of Image Quality and ADCs in Breath-Hold, Respiratory-Triggered and Free-Breathing DWI of Pancreas at 3-T

Objective: To compare image quality and apparent diffusion coefficients (ADC) of the normal pancreas parenchymas in breath-hold, respiratory-triggered and free-breathing diffusion weighted imaging (DWI) at 3.0-Tesla. Methods: DWI of the pancreas was performed at 3.0-Tesla in 21 healthy volunteers with breath-hold, respiratory-triggered and free-breathing using b-values of 0 and 500 s/mm2. For all three sequences, two readers assigned an image quality score to images at b0 and b500, and two independent readers measured ADCs for the head, body and tail of pancreas. Image quality scores and ADCs of pancreas in the three DWIs were compared. Results: For b0, image quality scores was not significantly different among the three sequences (p = 0.103). For b500, image quality score was significantly lower in free-breathing DWI than breath-hold or respiratory-triggered DWI (p = 0.000), and not significantly different between breath-hold and respiratory-triggered DWI (p = 0.212). Mean ADCs differed significantly among the anatomical regions with the lowest values measured in the pancreatic tail both at breath-hold and respiratory-triggered DWIs whereas no significant difference was found at free-breathing DWI. Conclusion: Breath-hold or respiratory-triggered technique provided DW images of pancreas with acceptable quality at 3.0-Tesla. Breath-hold is the preferred DWI technique for ADC measurements of pancreas.

A Longitudinal Study of Clinical Benefits with Implementation of the Deep Inspiration Breath-Hold Technique in Post-Operative Radiotherapy for Left-Sided Breast Cancer

Purpose/Objectives: We aimed to report clinical effects on critical organ dose and cardiac toxicity from implementation of the deep inspiration breath-hold (DIBH) technique in post-operative extern-beam radiotherapy of patients with left-sided breast cancer, using longitudinal clinical data. Materials/Methods: We retrieved three groups of patients who received post-operative radiotherapy of left-sided breast cancer in our institution in recent years: Groups A and B consist of patients whose treatment did not include internal mammary nodes (IMN) and who were treated with the free breathing technique and with the DIBH technique, respectively, and Group C consists of patients whose radiotherapy included internal mammary nodes with the DIBH technique. Dose parameters for the heart and left lung were retrieved from the treatment plans. Radiation-induced cardiac risks were estimated using existing risk models. Results: The average heart dose was 2.65 ± 0.98 Gy, 1.10 ± 0.29 Gy, and 1.26 ± 0.25 Gy in Groups A, B, and C, respectively. The average heart volumes receiving at least 25 Gy were 7.10 ± 9.79 cc in Group A, 0.07 ± 0.22 cc in Group B, and 0.03 ± 0.08 cc in Group C. On average, the excessive risk of having ischemic heart disease was estimated to be 19.6%, 8.1%, and 9.3% in Groups A, B, and C, respectively. The mean left lung doses were 5.73 ± 1.86 Gy, 5.93 ± 1.55 Gy, and 9.13 ± 1.57 Gy in Groups A, B, and C, respectively. Conclusion: Implementation of the DIBH technique significantly lowered heart dose and decreased the ischemic heart disease risk in patients receiving post-operative radiotherapy for left-sided breast cancer, without significant increase in left lung dose.

Deep Inspiration Breath Hold Reduces Dose to the Left Ventricle and Proximal Left Anterior Descending Artery during Radiotherapy for Left-Sided Breast Cancers

The purpose of this study was to analyze motion of the left anterior descending coronary artery (LAD) and left ventricle during normal breathing and deep inspiration breath hold (DIBH). This is a dosimetric study utilizing free-breathing and static DIBH scans from eleven patients treated with radiotherapy for breast cancer. The anterior-posterior displacement along the length of the LAD was measured in each respiratory phase. Standard treatment plans targeting the whole breast without treatment of the internal mammary lymph nodes were generated and dose to the LAD and LV calculated. Non-uniform movement of the LAD during respiratory maneuvers with the proximal third exhibiting the greatest displacement was observed. In DIBH compared to end-expiration (EP), the mean posterior displacement of the proximal 1/3 of the LAD was 8.99 mm, the middle 1/3 of the artery was 6.37 mm, and the distal 1/3 was 3.27 mm. In end-inspiration (IP) compared to end-expiration the mean posterior displacements of the proximal 1/3 of the LAD was 2.08 mm, the middle 1/3 of the artery was 0.91 mm, and the distal 1/3 was 0.97 mm. Mean doses to the LAD using tangential treatment fields and a prescribed dose of 50.4 Gy were 11.32 Gy in EP, 8.98 Gy in IP, and 3.50 Gy in DIBH. Mean doses to the LV were 2.38 Gy in EP, 2.31 Gy in IP, and 1.24 Gy in DIBH. In conclusion, inspiration and especially DIBH, cause a displacement of the origin and proximal 2/3 of the LAD away from the chest wall, resulting in sparing of the most critical segment of the artery during tangential radiotherapy.

A Half-Arc Multiple Deep-Inspiration Breath-Hold Volumetric Modulated Arc Therapy for a Lung Tumor with 10 MV Flattening-Filter-Free Beams and an Image Sensor Measuring a Distance Map to Thorax Surface: An Initial Clinical Experience

A technique for multiple deep-inspiration breath-hold (DIBH) volumetric modulated arc therapy (VMAT) for a lung tumor has been proposed with 10 MV flattening-filter-free beams and an image sensor measuring a distance map to thorax surface. Planning CT images were acquired under a DIBH condition and a clinical target volume (CTV) was contoured. This procedure was repeated five times and an internal target volume (ITV) among the multiple DIBHs was created by integrating the five CTVs. A planning target volume (PTV) was defined by adding an isotropic margin of 5 mm to the ITV. Immediately before treatment, a 30-second half-arc cone-beam computer tomography (CBCT) imaging was performed under another DIBH condition, and the couch was repositioned so that tumor may be located inside the PTV contours. An infrared distance measurement device having laser diodes and an image sensor was attached to the couch, and a distance map to the patient thorax surface was recorded as a reference during still another DIBH condition. A half-arc segmented VMAT beams with two beam interrupts were delivered to the patient under multiple DIBHs, where the delivery time of each of the three segmented beams was 30 seconds. During the beam delivery, the distance map was monitored in real time to confirm that the distance to the thorax surface remained unchanged. In-treatment CBCT images suggested that the tumor position at the time of tumor registration was accurately reproduced during the DIBH VMAT delivery.

Application of Deep Inspiration Breath Hold Technique in Radiotherapy After Breast- Conserving Surgery for Left Breast Cancer and Its Improvement on Cardiac Dose

Objective:To analyze the application of deep inspiration breath hold technique in radiotherapy after breast-conserving surgery for left breast cancer and the improvement of cardiac dose.Methods:A total of 45 patients with left breast cancer treated in our hospital after breast-conserving surgery were selected,and the selection time was set from January 2020 to August 2022.All patients received radiotherapy.The right breast,heart,and lung volumes,and dose parameters of the heart,lungs,right breast,and left anterior descending coronary artery were compared under free breathing(FB)and deep inspiration breath hold(DIBH)technical modes.Results:The heart volume of the DIBH group was smaller than that of the FB group,and the left and right lung volumes were significantly larger than those of the FB group.In the DIBH group,the heart dose parameters V5,proper lung dose parameters,and left anterior descending coronary artery dose parameters were found lower than that of the FB group,and the differences were statistically significant(P<0.05).Conclusion:Compared with FB,the DIBH technique can reduce the heart’s size and increase the lung volume when used for radiotherapy after breast-conserving surgery for left breast cancer.It also reduces the dose to the heart,right lung,and left anterior descending coronary artery,thus protecting the heart and lungs.

A Region Holds Its Breath

Death of Ethiopian leader Meles Zenawi brings stability concerns in the Horn THERE＇s no doubt that Ethiopia＇s deceased prime Minister Meles Zenawi was a key cog in the stability, development and security in the Horn of Africa. His footprints, for the 21 years that he was

The Clockls Ticking Is Africa’s relaxed attitude toward timekeeping holding the continent back?

Africa misappropriates time as it does to other resources, such as minerals. With this tradition, everything on the continent is always running behind schedule.

单次屏气3D-GRASE序列在MRI胰胆管成像的应用

目的探讨MRI单次屏气3D-GRASE成像技术在胰胆管的应用价值。方法选取本院57例胰胆管疾病患者,所有患者均进行自由呼吸自旋回波技术(3D-RT-TSE)和屏气梯度-自旋回波技术(3D-BH-GRASE)胰胆管水成像,分别记录两种成像方法的扫描时间;测量计算图像胆总管信噪比(SNR)、胆总管与其周围组织对比度(CR)及胆总管和肝脏之间对比噪声比(CNR),并由2位高年资医师分别对图像质量、伪影、背景抑制及胰胆管的显示进行评分。结果与3D-RT-TSE技术比较,3D-BH-GRASE技术扫描时间明显缩短,差异有统计学意义(t=70.995,P<0.001);3D-BH-GRASE的整体图像质量、伪影、胰胆管的效果评分均高于3D-RT-TSE,两种方法差异均有统计学意义(P均<0.05)。3D-BH-GRASE图像SNR、CR、CNR及图像背景抑制方面均小于3D-RT-TSE,差异均有统计学意义(P均<0.001)。结论相比呼吸触发(3D-RTTSE)序列,3D-BH-GRASE序列扫描时间更短,整体图像质量和胰胆管显示更好,值得进一步推广应用。

自由呼吸DISCO-Star序列在动态增强肝脏MRI中的可行性研究

目的 本研究旨在比较自由呼吸条件下的DISCO-Star序列与屏气时的LAVA序列在肝脏成像中的图像质量,并探讨DISCO-Star序列在肝脏扫描中的应用潜力。方法本研究回顾性分析了2023年12月至2024年3月期间,同时接受自由呼吸DISCO-Star序列及屏气LAVA序列检查的20名患者。两种序列的图像质量通过5点评分法进行评价。评价内容包括两位观察者的一致性、运动伪影、肝脏边缘的清晰度、扫描时机和总体图像质量。结果两位观察者在总体图像质量上显示出较高的一致性(K=0.814)。屏气LAVA序列图像在运动伪影、肝脏边缘清晰度、扫描时机方面以及图像总体质量的评分优于自由呼吸DISCO-Star序列图像,两组间的差异有统计学意义(P值均<0.05)。两组图像的可诊断性评分差异无统计学意义(P=1)。结论DISCO-Star序列在不需要患者屏气的情况下提供了与LAVA序列相媲美的图像质量,对于那些无法进行屏气操作的患者具有重要的临床意义,值得进一步推广应用。

对比Star-容积内插屏气检查序列与常规容积内插屏气检查序列胎儿脑图像质量

目的对比分析Star-容积内插屏气检查(Star-VIBE)序列及常规容积内插屏气检查(VIBE)序列胎儿脑图像质量。方法对81名妊娠中晚期孕妇分别行Star-VIBE序列(自由呼吸)及常规VIBE序列MR体部扫描,比较2种序列图像中胎儿基底核及脑白质部位SNR及CNR,并比较胎儿脑沟回、基底核及丘脑、脑室系统、小脑及脑干部位2种序列图像质量评分。结果胎儿基底核及脑白质部位Star-VIBE序列图像的SNR、CNR均高于常规VIBE序列(P均<0.01)。胎儿脑沟回、基底核及丘脑、脑室系统、小脑及脑干部位Star-VIBE序列图像质量评分均高于常规VIBE序列(P均<0.01)。结论 Star-VIBE序列扫描获得的胎儿脑图像质量好于常规VIBE序列,显示胎儿颅内结构更清晰。

屏气发作儿童的12导联心电图P波、T波及ST段振幅变化

目的：探讨屏气发作儿童12导联心电图的P波、T波及ST段振幅变化。方法：收集2009年10月至2015年9月在中南大学湘雅二医院儿童心脏专科门诊就诊、明确诊断为屏气发作的儿童29例（研究组）,年龄3个月~6（1.82±1.27）岁,男24例,女5例。按性别及年龄匹配同期在中南大学湘雅二医院儿童保健专科门诊进行健康检查的儿童30例为对照组。采用广东中山博爱医用电子仪器厂的SR-1000A心电综合自动分析仪对受检者进行12导联心电图描记,比较两组儿童心电图变化。结果：与对照组比较,研究组V5导联P波振幅降低[（44.10±23.98）vs（58.30±21.19）μV,P〈0.05];V6导联T波振幅增高[（423.80±122.60）vs（350.00±105.73）μV,P〈0.05];ST段振幅在Ⅱ导联增高[（84.80±39.97）vs（57.30±38.77）μV,P〈0.05],a VR导联负向增大[（–77.60±37.41）vs（–51.00±33.46）μV,P〈0.05],a VL导联增高[（35.20±28.24）vs（17.7±33.9）μV,P〈0.05],V5导联增高[（111.00±59.36）vs（69.00±36.33）μV,P〈0.05],V6导联增高[（79.3±45.51）vs（51.3±33.19）μV,P〈0.05]。结论：屏气发作儿童存在自主神经功能障碍,ST段振幅变化较为敏感。

D-S证据理论在小电流故障选线中的应用研究

介绍了在不同的情况下选取适当的故障选线算法来处理故障信息,并对故障信息进行D-S证据理论的信息融合,提高了故障选线的准确率.指出如何将选取的群体比幅比相算法和小波分析方法进行改进以适合证据理论的融合,如何设计算法计算D-S证据理论中的不确定性问题.

3D SPACE与屏气压缩感知技术在MRCP成像中的对比研究

目的探讨压缩感知(Compressed Sensing,CS)技术在屏气磁共振胰胆管造影(Magnetic Resonance Cholangiopancreatography,MRCP)中的临床应用价值。方法对40例患者同时行膈肌导航3D可变反转角快速自旋回波(Sampling Perfection with Application-Optimized Contrast Using Different Flip-Angle Evolutions,SPACE)MRCP和屏气压缩感知3D MRCP(欠采样率3.6%)序列扫描,根据序列不同将图像分为SPACE-MRCP和CS-MRCP 2组。定性分析2组图像整体质量、背景抑制效果和胰管的显示能力;定量分析2组图像的扫描时间、信噪比(Signal to Noise Ratio,SNR)和对比噪声比(Contrast to Noise Ratio,CNR)。结果图像整体质量评分、背景抑制效果方面,CS-MRCP均优于SPACE-MRCP,差异有统计学意义(P<0.05)。胰管显示能力方面,CS-MRCP与SPACE-MRCP相当,差异无统计学意义(P<0.05);SPACE-MRCP和CS-MRCP扫描时间分别为(260.95±61.70)、17 s,差异有统计学意义(P<0.05)。SNR和CNR分析中,CS-MRCP均优于SPACE-MRCP,差异有统计学意义(P<0.05)。结论采用压缩感知技术的屏气MRCP序列与膈肌导航3D SPACE序列相比,可显著缩短扫描时间,获得更好的图像质量。

3.0T屏气3D GRASE-MRCP序列的优化

目的通过采用不同的TSE factor、EPI factor组合,将屏气3D GRASE-MRCP序列的扫描时间缩短至15秒以内,并选出图像质量较佳的TSE factor、EPI factor组合。方法在3.0T上对31例患者分别采用5组不同TSE factor、EPI factor组合的3D GRASE-MRCP序列进行扫描,扫描时间均在15秒以内,对所得5组图像胆总管的对比信噪比(CNR)进行方差分析及两两对比;由三名高年资的影像科医师对5组序列的成像效果目测评分,组间对比采用Kruskal-Wallis H检验及两两对比。结果 5组图像的胆总管CNR中,组1(14*7)、组3(13*7)、组4(14*5)的CNR显著高于组5(14*9),其它组间两两对比CNR均没有显著差异。专家目测评分,组1评分显著高于组4、组5,组1与组2、3间无显著统计学差异。结论优化后的3D GRASE-MRCP序列扫描时间可缩短至15秒以内,更适用于临床。综合CNR定量分析及专家目测评分的结果,TSE factor、EPI factor的组合为14*7时图像质量较佳。

垂直方向支抗控制与行PASS矫治技术中的上颌前突病儿童颌平面角变化、颏部形态的关系

目的:探讨采用垂直方向支抗控制(VHA)与行生理性支抗(PASS)矫治技术治疗儿童上颌前突病,对其颌平面角变化、颏部形态的影响情况。方法:选取76例上颌前突儿童为研究对象,将所有患儿根据随机数字表法分为VHA组和未行VHA组,2组患儿均采用PASS矫治术进行矫治,VAH组在此基础上进行垂直方向的支抗控制。结果:VHA支抗对于上中切牙的唇向前突有明显改善(P<0.01),支抗控制联合VHA对于牙齿矫形后牙齿在垂直方向上的生长有较好控制(P<0.05~P<0.01),从使病人下颌骨在逆时针上前上方旋转,出现治疗后下颌骨向前旋转,治疗前后差异具有统计学意义(P<0.05~P<0.01)。结论:对于小儿上颌前突的治疗,特别对于比较困难的矫治病例,往往需要使用各种不同的治疗措施使支抗得到加强,因此能够有简单高效的增强支抗的方式(如垂直方向支抗控制)尤为重要,能够使治疗效果得到提高,使病人满意。

0.5T ELSCINT系统序列改型实现腹部动态增强屏气扫描

目的 开发 0 .5TELSCINT系统中腹部脏器的 3期动态强化屏气扫描序列。方法 对本系统原序列D GE 2D VC SEQ .DPRIV GRECA112 .PXD序列参数进行调整后 ,获得T1对比度图像 ,并将成像时间缩短到 2 2s左右 ,对 2例肝脏转移瘤、4例血管瘤应用本技术进行多时相动态屏气强化检查。结果 转移瘤动脉期增强 1例 ,延迟期增强 1例 ,血管瘤表现为动脉期边缘明显强化 ,逐渐填充。结论 应用改进序列 ,在 0 .5TELSCINT系统上可以实现动态强化屏气扫描 ,为肝脏肿瘤的鉴别诊断提供依据。