105例老年妇女宫颈癌的放射治疗

1990年2月至1996年7月本院对105例60岁以上的宫颈癌患者实施根治性放疗,为了探讨哪一类后装治疗机更适合老年患者的腔内放疗,作者比较了137铯和192铱的放疗效果,其结果如下.     

钴(60Co)源外放疗加后装治疗宫颈癌疗效观察

目的：采用^60Co源对宫颈癌行外放疗加后装治疗,观察疗效及副反应。方法：52例宫颈癌病人行外放疗加后装治疗。结果：3年生存率占79％。并发症有腹痛腹泻,大便坠帐、乏力纳差、骨髓抑制等,晚期反应主要是放射性肠炎、膀胱炎、阴道分泌物少、狭窄。结论：采用钴源对宫颈癌行外放疗加后装治疗,效果肯定,副反应轻,但局部复发率仍高．远期反应存在。     

Qualitative Evaluation of a Novel 3D Volumetric Radiotherapy Segmentation Tool

IntroductionA novel 3D volumetric segmentation tool allows the user to outline using a small number of points on a range of planes. Unique 3D volumetric “sculpting” tools enable editing of the resulting structures across multiple slices concurrently. This article reports the results of radiation oncologists' preclinical evaluation of the tool.MethodsThree clinicians outlined prostate and seminal vesicles on 14 data sets using the traditional slice-by-slice method and the new 3D tool. The project gathered focus-group feedback to gather rich data relating to clinician perceptions of the new 3D outlining paradigm. Emergent themes were identified and categorised for discussion.ResultsRadiation oncologists reported high levels of satisfaction with the outlines arising from both paradigms. The volumetric sculpting was a challenge, but participants enjoyed using points in orthogonal planes and felt that the paradigm had potential value in terms of speed and smooth volume creation.ConclusionThis study has demonstrated that a 3D volumetric outlining system is felt to have potential value by radiation oncologists for accelerating clinician-directed prostate and seminal vesicle segmentation. The new tool was well-received and reported to be capable of producing very rapid and smooth volumes. The novelty of the approach required significant training input and a radically different approach of minimal point placement. Further testing of this software with a less time-poor cohort may be indicated to gain reliable quantitative data relating to the impact on segmentation time.     

Evaluation of Pre-malignant Lesions of the Uterine Cervix by Shear Wave Elastography: A New Diagnostic Tool

The objective of the study was to evaluate the difference in the stiffness between a healthy cervix (no pre-invasive lesions [NPILs]) and a cervix with a pre-invasive lesion (PIL). In the PIL group, we determined whether there was a difference in stiffness between the cervix with persistent low-grade lesions (>2 y, LSIL-persistent) and that with high-grade lesions (HSILs). Evaluation was performed using 2-D shear-wave elastography (SWE) in the midsagittal-plane of the uterine cervix (UC) at 0.5 cm (cervical canal, anterior and posterior cervical lips). In this prospective observational study (consecutive series), we evaluated 96 non-pregnant women: a group with PIL (LSIL-persistent, 22 cases; HSIL, 26 cases) with indications for cervical conization (48 cases) and a group without UC pathology (NPIL, 48 cases). Although we did not observe statistically significant differences (SSDs) in epidemiological characteristics, we did find an SSD in the speed and stiffness between the PIL versus NPIL groups at all evaluated depths (speed: 4.1 m/s vs 3.0 m/s, stiffness: 58.6 and 34.5kPa in the PIL and NPIL groups, respectively, p < 0.001). An SSD in speed and stiffness (speed: 4.9 m/s vs. 3.2 m/s, and stiffness: 76.1 and 38.0 kPa) between the HSIL (26 cases) and LSIL-persistent (22 cases) groups, respectively, was also detected (p < 0.001). The area under the curve of speed differentiation between a cervix with HSILs and without lesions was 73.4% (95% confidence interval [CI]: 63.1–83.7), and the best cutoff of speed was 3.25 m/s (sensitivity = 62.5%, 95% CI: 47.3–76.0), with a specificity of 75.5% (95% CI: 60.4–87.1).     

3-D Ultrasound Segmentation of the Placenta Using the Random Walker Algorithm: Reliability and Agreement

Volumetric segmentation of the placenta using 3-D ultrasound is currently performed clinically to investigate correlation between organ volume and fetal outcome or pathology. Previously, interpolative or semi-automatic contour-based methodologies were used to provide volumetric results. We describe the validation of an original random walker (RW)-based algorithm against manual segmentation and an existing semi-automated method, virtual organ computer-aided analysis (VOCAL), using initialization time, inter- and intra-observer variability of volumetric measurements and quantification accuracy (with respect to manual segmentation) as metrics of success. Both semi-automatic methods require initialization. Therefore, the first experiment compared initialization times. Initialization was timed by one observer using 20 subjects. This revealed significant differences (p < 0.001) in time taken to initialize the VOCAL method compared with the RW method. In the second experiment, 10 subjects were used to analyze intra-/inter-observer variability between two observers. Bland–Altman plots were used to analyze variability combined with intra- and inter-observer variability measured by intra-class correlation coefficients, which were reported for all three methods. Intra-class correlation coefficient values for intra-observer variability were higher for the RW method than for VOCAL, and both were similar to manual segmentation. Inter-observer variability was 0.94 (0.88, 0.97), 0.91 (0.81, 0.95) and 0.80 (0.61, 0.90) for manual, RW and VOCAL, respectively. Finally, a third observer with no prior ultrasound experience was introduced and volumetric differences from manual segmentation were reported. Dice similarity coefficients for observers 1, 2 and 3 were respectively 0.84 ± 0.12, 0.94 ± 0.08 and 0.84 ± 0.11, and the mean was 0.87 ± 0.13. The RW algorithm was found to provide results concordant with those for manual segmentation and to outperform VOCAL in aspects of observer reliability. The training of an additional untrained observer was investigated, and results revealed that with the appropriate initialization protocol, results for observers with varying levels of experience were concordant. We found that with appropriate training, the RW method can be used for fast, repeatable 3-D measurement of placental volume.     

Developing an Adaptive Radiotherapy Technique for Virally Mediated Head and Neck Cancer

BackgroundVirally mediated head and neck cancers (VMHNC) often present with nodal involvement and are highly radio responsive, meaning that treatment plan adaptation during radiotherapy (RT) in a subset of patients is required. This study sought to determine potential risk profiles and a corresponding adaptive treatment strategy for these patients.MethodologyOne hundred twenty-one patients with virally mediated, node positive nasopharyngeal (Epstein-Barr virus positive) or oropharyngeal (human papillomavirus positive) cancers who were receiving curative intent RT were reviewed. The type, frequency, and timing of adaptive interventions, including source-to-skin distance (SSD) corrections, rescanning, and replanning, were evaluated. Patients were reviewed based on the maximum size of the dominant node to assess the need for plan adaptation.ResultsForty-six patients (38%) required plan adaptation during treatment. The median fraction at which the adaptive intervention occurred was 26 for SSD corrections and 22 for replanning CTs. A trend toward three risk profile groupings was discovered: (1) low risk with minimal need (<10%) for adaptive intervention (dominant pretreatment nodal size of ≤35 mm), (2) intermediate risk with possible need (<20%) for adaptive intervention (dominant pretreatment nodal size of 36–45 mm), and (3) high risk with increased likelihood (>50%) for adaptive intervention (dominant pretreatment nodal size of ≥46 mm).ConclusionsIn this study, patients with VMHNC and a maximum dominant nodal size of >46 mm were identified at a higher risk of requiring replanning during a course of definitive RT. Findings will be tested in a future prospective adaptive RT study.     

Adaptive scan sequence for real-time ultrasound 3-D imaging

An adaptive scan sequence is proposed for real-time ultrasound three-dimensional (3-D) imaging. Generally, the refresh rate of 3-D imaging is limited by the view window, resolution and sound speed in the human body. If the object is transformed or moved during the data set acquisition, the 3-D image will be distorted. To realize a high refresh rate for 3-D imaging, a reduction of the number of transmissions is required. Using a small number of transmissions results in a small view window or low resolution. In this paper, we propose a method to adaptively modify the spatial and temporal beam density according to the local motion of the object. We present 3-D images of a phantom with high frame rate, high resolution and wide view-angle window, significantly reducing the size of the full real scan raw data set.     

无痛技术在宫颈电圈切除术中的临床应用

【目的】探讨丙泊酚联合小剂量氯胺酮麻醉在高频电波刀的电圈切除（LEEP）术中的临床应用效果.【方法】门诊40例拟行LEEP术的女性患者分为Ⅰ组麻醉组（n=20）,依次静注氯胺酮0.2～0.4 mg/kg、丙泊酚1～2 mg/kg,术中按需单次加入丙泊酚20～40 mg.Ⅱ组为无麻醉组（n=20）.【结果】Ⅰ组的镇痛效果明显好于Ⅱ组（P〈0.01）.Ⅱ组手术时收缩压（SBP）、平均动脉压（MAP）、心率（HR）明显升高（P〈0.05）.Ⅰ组与Ⅱ组比较,手术中、手术后SBP、MAP变化显著低于Ⅱ组（P〈0.01）.【结论】丙泊酚复合小剂量氯胺酮麻醉应用于高频电波刀的电圈切除术是一种安全、有效的麻醉方法.     

Feasibility of Ultrasound-Based Computational Fluid Dynamics as a Mitral Valve Regurgitation Quantification Technique: Comparison with 2-D and 3-D Proximal Isovelocity Surface Area-Based Methods

Current Doppler echocardiography quantification of mitral regurgitation (MR) severity has shortcomings. Proximal isovelocity surface area (PISA)-based methods, for example, are unable to account for the fact that ultrasound Doppler can measure only one velocity component: toward or away from the transducer. In the present study, we used ultrasound-based computational fluid dynamics (Ub-CFD) to quantify mitral regurgitation and study its advantages and disadvantages compared with 2-D and 3-D PISA methods. For Ub-CFD, patient-specific mitral valve geometry and velocity data were obtained from clinical ultrasound followed by 3-D CFD simulations at an assumed flow rate. We then obtained the average ratio of the ultrasound Doppler velocities to CFD velocities in the flow convergence region, and scaled CFD flow rate with this ratio as the final measured flow rate. We evaluated Ub-CFD, 2-D PISA and 3-D PISA with an in vitro flow loop, which featured regurgitation flow through (i) a simplified flat plate with round orifice and (ii) a 3-D printed realistic mitral valve and regurgitation orifice. The Ub-CFD and 3-D PISA methods had higher precision than the 2-D PISA method. Ub-CFD had consistent accuracy under all conditions tested, whereas 2-D PISA had the lowest overall accuracy. In vitro investigations indicated that the accuracy of 2-D and 3-D PISA depended significantly on the choice of aliasing velocity. Evaluation of these techniques was also performed for two clinical cases, and the dependency of PISA on aliasing velocity was similarly observed. Ub-CFD was robustly accurate and precise and has promise for future translation to clinical practice.     

Method for Carotid Artery 3-D Ultrasound Image Segmentation Based on CSWin Transformer

Precise segmentation of carotid artery (CA) structure is an important prerequisite for the medical assessment and detection of carotid plaques. For automatic segmentation of the media–adventitia boundary (MAB) and lumen–intima boundary (LIB) in 3-D ultrasound images of the CA, a U-shaped CSWin transformer (U-CSWT) is proposed. Both the encoder and decoder of the U-CSWT are composed of hierarchical CSWT modules, which can capture rich global context information in the 3-D image. Experiments were performed on a 3-D ultrasound image data set of the CA, and the results indicate that the U-CSWT performs better than other convolutional neural network (CNN)-based and CNN–transformer hybrid methods. The model yields Dice coefficients of 94.6 ± 3.0% and 90.8 ± 5.1% for the MAB and LIB in the common carotid artery (CCA) and 92.9 ± 4.9% and 89.6 ± 6.2% for MAB and LIB in the bifurcation, respectively. Our U-CSWT is expected to become an effective method for automatic segmentation of 3-D ultrasound images of CA.     

3-D Quantitative Dynamic Contrast Ultrasound for Prostate Cancer Localization

To investigate quantitative 3-D dynamic contrast-enhanced ultrasound (DCE-US) and, in particular 3-D contrast-ultrasound dispersion imaging (CUDI), for prostate cancer detection and localization, 43 patients referred for 10–12-core systematic biopsy underwent 3-D DCE-US. For each 3-D DCE-US recording, parametric maps of CUDI-based and perfusion-based parameters were computed. The parametric maps were divided in regions, each corresponding to a biopsy core. The obtained parameters were validated per biopsy location and after combining two or more adjacent regions. For CUDI by correlation (r) and for the wash-in time (WIT), a significant difference in parameter values between benign and malignant biopsy cores was found (p?<?0.001). In a per-prostate analysis, sensitivity and specificity were 94% and 50% for r, and 53% and 81% for WIT. Based on these results, it can be concluded that quantitative 3-D DCE-US could aid in localizing prostate cancer. Therefore, we recommend follow-up studies to investigate its value for targeting biopsies.     

Automatic Shape-Based Level Set Segmentation for Needle Tracking in 3-D TRUS-Guided Prostate Brachytherapy

Prostate brachytherapy is an effective treatment for early prostate cancer. The success depends critically on the correct needle implant positions. We have devised an automatic shape-based level set segmentation tool for needle tracking in 3-D transrectal ultrasound (TRUS) images, which uses the shape information and level set technique to localize the needle position and estimate the endpoint of needle in real-time. The 3-D TRUS images used in the evaluation of our tools were obtained using a 2-D TRUS transducer from Ultrasonix (Richmond, BC, Canada) and a computer-controlled stepper motor system from Thorlabs (Newton, NJ, USA). The accuracy and feedback mechanism had been validated using prostate phantoms and compared with 3-D positions of these needles derived from experts' readings. The experts' segmentation of needles from 3-D computed tomography images was the ground truth in this study. The difference between automatic and expert segmentations are within 0.1 mm for 17 of 19 implanted needles. The mean errors of automatic segmentations by comparing with the ground truth are within 0.25 mm. Our automated method allows real-time TRUS-based needle placement difference within one pixel compared with manual expert segementation.     

早期子宫内膜癌术后放疗效果的系统评价

目的系统评价术后放疗对早期子宫内膜癌的有效性、安全性及成本-效果：方法电子检索Cochrane图书馆、MEDLINE、EMbase、CancerLit、CBMdisc、VIP、万方学位论文数据库、CNKI,并辅以手丁检索j检索时间截至2007年3月,收集子宫内膜癌（EC）术后放疗的随机对照试验（RCT）。由两名研究者按Cochrane系统评价方法,独立选择试验,提取资料、评价纳入研究的方法学质量,并提取有效数据进行Meta分析：结果共纳入7个RCT,包括2084例患者,其中5个为术后放疗（盆腔和／或阴道）与术后非放疗比较,包括1254例患者;1个为阴道放疗不同剂量间的比较（2．5GyVS5．0Gy）,包括290例患者;1个为两种放疗方式的比较（阴道＋盆腔VS阴道）,包括540例患者.Meta分析结果显示：（1）手术VS手术＋放疗：①手术VS手术＋盆腔放疗：5、8、10年局部复发率及5、8年总体复发率,手术＋盆腔放疗组低于单纯手术组;两组5、8年远处复发率及5、8、10年总体生存率差异无统计学意义;10年远处复发率手术十盆腔放疗组高于单纯手术组;两组10年总体复发率差异无统计学意义;②手术VS手术＋阴道放疗：5、10年总体生存率及5、10年无瘤生存率,两组差异无统计学意义：（2）手术＋内分泌治疗VS手术＋盆腔放疗：两组局部及远处复发率、总体生存率及无瘤生存率（〈2年）差异均无统计学意义：（3）术后阴道放疗两种不同剂量（2．5GyVS5．0Gy）的比较：5年复发率（局部、远处、总体）及5年总体生存率、毒性反应,两组差异均无统计学意义：（4）手术＋阴道放疗VS手术＋阴道放疗＋盆腔放疗：5年局部复发率联合放疗组低于单独阴道放疗组,5年远处复发率联合放疗组高于单独阴道放疗组,5年总体生存率两组无统计学差异：{5）成本-效果分析：术后放疗比复发后放疗虽增加了成本但却提高了总体生存率,术后高剂量近距离放疗成本-效果价值较好：结论术后放疗对于子宫内膜癌Ⅰ期患者．能有效降低其局部复发率,但对远处复发率、总体生存率、无瘤生存率无明显改善,疗效和单纯手术效果相似;放疗的副作用较单纯手术大。因各试验纳入研究人群不完全一致,且亚组分析发现内膜癌的死因绝大多数并非由子宫内膜癌本身或治疗引起,而是死于其合并症,故放疗对子宫内膜癌患者的总体生存率、无瘤生存率的效果有待进一步大样本、高质量的多中心随机双盲对照试验加以证实。     

Adaptive Remodeling of Trabecular Bone Core Cultured in 3-D Bioreactor Providing Cyclic Loading: An Acoustic Microscopy Study

Scanning acoustic microscopy (SAM) provides high-resolution mapping of acoustic impedance related to tissue stiffness. This study investigates changes in tissue acoustic impedance resulting from mechanical loading in trabecular bone cores cultured in 3-D bioreactor. Trabecular bone cores were extracted from bovine sternum (n = 15) and ulna metaphysis (n = 15). From each bone, the samples were divided in three groups. The basal control (BC) group was fixed post-extraction, the control (C) and loaded (L) groups were maintained as viable in a controlled culture-loading cell over three weeks. Samples of L group underwent a dynamic compressive strain, whereas C samples were left free from loading. After three weeks, L and C samples were embedded in polymethylmethacrylate and all samples were explored with a 200-MHz SAM. For each specimen, the acoustic impedance distribution was obtained over flat and polished section of bone blocks prepared parallel to the loading axis. Our results showed that in basal controls, the acoustic impedance varied with bone anatomical location and was 15% higher in weight-bearing ulna compared with nonweight-bearing sternum. The comparison between loaded and nonloaded groups showed that sternum-only exhibited significant change in acoustic impedance (L vs. C sternum: +9%). This result suggests that when the applied load is comparable with the stress naturally experienced by a weight-bearing bone (ulna), the tissue material properties (manifested by acoustic impedance) remained unchanged. In conclusion, SAM is a potentially relevant tool for the assessment of subtle changes in intrinsic microelastic properties of bone induced by adaptive remodeling process in response to mechanical loading. (E-mail: amena.saied@upmc.fr)     

3-D Ultrasound and Thyroid Cancer Diagnosis: A Prospective Study

This study tests the hypothesis that evaluation of thyroid nodule (TN) margin irregularities by three-dimensional ultrasound (3-D-US) distinguishes benign from malignant TNs with greater sensitivity and specificity than two-dimensional ultrasound (2-D-US). We prospectively evaluated 344 TNs using both 2-D-US and 3-D-US followed by fine needle aspiration biopsy. TNs were divided into four groups based on the 3-D-US appearance of the margins. Bi-variate and multi-variate analyses were used. Surgical pathology confirmed 44 thyroid cancers in 40 patients. For 2-D-US, irregular margins and micro-calcifications (p < 0.001) were found more frequently in malignant TNs. Irregular margins on 2-D-US had a sensitivity and specificity of 61.4% and 79.3%, respectively. Irregular margins on 3-D-US had a sensitivity and specificity of 86.4% and 83.3%, respectively. Sensitivity, specificity, positive and negative predictive values were higher for irregular margins on 3-D-US than micro-calcifications and irregular margins on 2-D-US. Evaluation of TN margins by 3-D-US distinguished benign from malignant TNs with greater sensitivity and specificity than 2-D-US.     

3-D Multi-parametric Contrast-Enhanced Ultrasound for the Prediction of Prostate Cancer

Trans-rectal ultrasound-guided 12-core systematic biopsy (SBx) is the standard diagnostic pathway for prostate cancer (PCa) because of a lack of sufficiently accurate imaging. Quantification of 3-D dynamic contrast-enhanced ultrasound (US) might open the way for a targeted procedure in which biopsies are directed at lesions suspicious on imaging. This work describes the expansion of contrast US dispersion imaging algorithms to 3-D and compares its performance against malignant and benign disease. Furthermore, we examined the feasibility of a multi-parametric approach to predict SBx-core outcomes using machine learning. An area under the receiver operating characteristic (ROC) curve of 0.76 and 0.81 was obtained for all PCa and significant PCa, respectively, an improvement over previous US methods. We found that prostatitis, in particular, was a source of false-positive readings.     

Management of Thyroid Follicular Proliferation: An Ultrasound-Based Malignancy Score to Opt for Surgical or Conservative Treatment

This study was conducted to evaluate whether ultrasound characteristics of thyroid nodules with a known cytologic diagnosis of “follicular pattern” (indicative of follicular hyperplasia, follicular adenoma or follicular carcinoma) can be used to define a nodule malignancy score to limit surgery to selected, higher-risk cases. In pre-operative ultrasound results of patients diagnosed with a “follicular pattern” on cytology who subsequently underwent surgery, each nodule feature was given a score from 0 (most likely benign) to 2 (most likely malignant), resulting in a total score ranging from 0 to 11. The total nodule score (total malignancy score) was then compared with the definitive histologic diagnosis. According to our results, surgery is advisable in patients with score ≥4 (79% of carcinomas), ultrasound follow-up seems to be appropriate for patients with a score of 3 (21% of carcinomas) and no action is recommended for patients with score <3 (only benign nodules).     

An Algorithm for the Treatment of Pain in Advanced Cancer

An algorithm is presented that has been developed over the past three years to provide pain relief in advanced cancer. The hospital records of 92 patients were reviewed to evaluate the validity of the algorithm. The algorithm is as follows: the 24 hour oral consumption of opioids was converted to sustained release morphine. If ineffective usually over 360?mg daily the total 24 hour oral dose was divided by 6 to convert to I.V. If this was ineffective, usually over 10?mg/hr of morphine, the intravenous dose was divided by 10 and infused epidurally. Local anesthetic was added for plexus involvement. After four days, the patient was weaned from local anesthetic solution. If sharp pain or pain to movement persisted, 6% phenol in 1 to 2?ml aliquots was injected every 8-12 hours to a total of 5-8?ml. While the conversion from intravenous to epidural morphine was 10:1 that from epidural to intravenous was only 1:3. Intravenous dose converts directly to the subcutaneous. The conversion from intravenous to oral is 1:3. There view showed that the dosages at which the conversions were made varied considerably. The reasons for the wide variation are presented. In summary the algorithm is a good practical guide for treatment of cancer pain.