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61.
《Clinical oncology (Royal College of Radiologists (Great Britain))》2021,33(9):e403-e411
Radiotherapy and brachytherapy are the definitive treatments for locally advanced cervix cancer. The use of soft-tissue imaging, particularly magnetic resonance imaging, has enhanced their effectiveness and improved clinical outcomes. However, the use of magnetic resonance imaging is largely restricted to well-resourced centres in both the first and developing world and remains elusive to many less advantaged centres, particularly those in areas with a high burden of cervix cancer. Ultrasound is an accessible, affordable and accurate imaging modality that can be used throughout the brachytherapy procedure. Ultrasound is primarily used to ensure safe insertion of the applicator but can also be used to guide planning. The methods used to utilise ultrasound images for planning are described. Ultrasound is particularly useful as a verification aid to confirm applicator placement after patients are moved and transferred around the radiotherapy department. It can also be used to verify the dimensions of treatment volumes over the course of brachytherapy. There is a crucial unmet need for an accessible economical soft-tissue imaging modality in cervical brachytherapy. Ultrasound has the potential to meet this need. 相似文献
62.
Anthony Z Faranesh Dara L Kraitchman Elliot R McVeigh 《Magnetic resonance in medicine》2006,55(5):1114-1123
The purpose of this work was to investigate the use of an intravascular contrast agent to determine perfusion kinetics in skeletal muscle. A two-compartment kinetic model was used to represent the flux of contrast agent between the intravascular space and extravascular extracellular space (EES). The relationship between the image signal-to-noise ratio (SNR) and errors in estimating permeability surface area product (Ktrans), interstitial volume (ve), and plasma volume (vp) for linear and nonlinear curve-fitting methods was estimated from Monte Carlo simulations. Similar results were obtained for both methods. For an image SNR of 60, the estimated errors in these parameters were 10%, 22%, and 17%, respectively. In vivo experiments were conducted in rabbits to examine physiological differences between these parameters in the soleus (SOL) and tibialis anterior (TA) muscles in the hind limb. Values for Ktrans were significantly higher in the SOL (3.2+/-0.9 vs. 2.0+/-0.5x10(-3) min-1), as were values for vp (3.4+/-0.8 vs. 2.1+/-0.7%). Differences in ve for the two muscles (8.7+/-2.2 vs. 8.5+/-1.6%) were not found to be significant. These results demonstrate that relevant physiological metrics can be calculated in skeletal muscle using MRI with an intravascular contrast agent. 相似文献
63.
实时超声引导下显微手术切除脑深部病灶 总被引:3,自引:0,他引:3
目的探讨术中超声引导在脑深部病灶显微手术中的应用价值。方法自2004年开始我们在脑深部病灶显微手术中采用实时超声引导病灶定位,指引手术中皮层入路及路径的选择,并使用术中超声影像动态了解病变位置的变化情况、手术切除的范围,利用实时影像辅助判断病变切除程度。结果28例脑深部病灶,病灶直径为1.0~5.9cm,病理诊断包括蛛网膜囊肿5例,海绵状血管瘤2例,动静脉畸形2例,肿瘤7例,脑内血肿12例。所有病例均显微镜下全切,术后28例患者均恢复良好,神经功能保存良好,无新的神经功能损害,无手术并发症。结论术中超声引导是一种简便有效的脑深部病灶定位方法,操作简便,定位准确,能够实时指引手术路径和动态了解手术切除病灶的范围,与显微神经外科配合能够有效地避免额外的手术损伤,提高手术精度。 相似文献
64.
65.
J. M. Troyano M. T. Clavijo A. Gonzalez-Lorenzo I. Martí nez-Wallin O. Y. Marco P. S. Casas L. Martí nez-Cort s L. T. Merc J. Bajo-Arenas N. Hernandez D. Castro 《The Ultrasound Review of Obstetrics & Gynecology》2006,6(1):79-99
In order to assess the state and pathology of the woman's pelvis minor, a number of methods are commonly used among practitioners, encompassing clinical exploration, radiology, MRN, urodynamics, endoscopy and echography.
Echography has been poorly used in clinical pelvic exploration and its reliability is actually a matter of controversy 1. However, echographic surveys can provide us with valuable gynecological data on the state and pathologies of the soft pelvis, within the genital regions or even going beyond them, i.e. the rectal channel, bladder, urethra, anus, vascular plexuses, and all of their supporting tissues.
At our research unit, we have been employing Transvaginal Ultrasound echography (TVU) for a long time in conjunction with other pelvis-focused methods in order to study different kinds of pelvic alterations. TVU has proven to be friendly to use, fast, harmless and inexpensive, allowing serial explorations and producing high-quality dynamic images (loop-cinema, video-tape). Furthermore, this method is fairly aseptic in that the occurrence of faeces in the rectal ampolla is not a nuisance but a bonus in tracking the contours of the rectum walls and other topographical features which would be otherwise difficult to survey.
A complete pelvic floor TVU may add no longer than 5-8 minutes to a routine gynecological examination, can be implemented by the general gynecologist and generates data that can be further studied by the appropriate specialist for a more insightful evaluation 2. 相似文献
Echography has been poorly used in clinical pelvic exploration and its reliability is actually a matter of controversy 1. However, echographic surveys can provide us with valuable gynecological data on the state and pathologies of the soft pelvis, within the genital regions or even going beyond them, i.e. the rectal channel, bladder, urethra, anus, vascular plexuses, and all of their supporting tissues.
At our research unit, we have been employing Transvaginal Ultrasound echography (TVU) for a long time in conjunction with other pelvis-focused methods in order to study different kinds of pelvic alterations. TVU has proven to be friendly to use, fast, harmless and inexpensive, allowing serial explorations and producing high-quality dynamic images (loop-cinema, video-tape). Furthermore, this method is fairly aseptic in that the occurrence of faeces in the rectal ampolla is not a nuisance but a bonus in tracking the contours of the rectum walls and other topographical features which would be otherwise difficult to survey.
A complete pelvic floor TVU may add no longer than 5-8 minutes to a routine gynecological examination, can be implemented by the general gynecologist and generates data that can be further studied by the appropriate specialist for a more insightful evaluation 2. 相似文献
66.
目的:为更清晰地显示顽固性气胸的漏气部位和性质,为不能耐受手术者摸索一种新的治疗手段。方法:选择18例患者,先用76%泛影葡胺行胸膜腔造影,而后在局部注入少量粘连剂。结果:造影后发现多发性肺大泡8例,单发性肺大泡6例,肺大泡伴粘连带4例。病变分别位于左上肺,右上肺,中下肺野及叶间裂。注射粘连剂后,15例一次成功,3例第二次成功。随防6~18个月,未见复发。结论:该方法易掌握,无明显副作用。病变显示明显,易被患者接受,具有明显的临床效果和推广价值 相似文献
67.
B超引导下经皮肺穿刺针吸活检对周围型肺肿块的诊断价值 总被引:1,自引:0,他引:1
目的探讨B超引导下经皮肺穿刺针吸活检对周围型肺肿块的诊断价值。方法对31例患者施行B超引导肺穿刺针吸活检56次,进行细胞学和细菌学检查。结果穿刺取材成功率为93.6%,所获细胞学资料与手术病理诊断或临床治疗随访对照,定性诊断符合率为89.7%。结论该诊断方法简便实用,并发症轻微,适于临床推广应用。 相似文献
68.
Spleen sizing by ultrasound in polycythaemia and thrombocythaemia: comparison with SPECT 总被引:3,自引:1,他引:2
M. Messinezy L. M. MacDonald T. O. Nunan N. B. Westwood S. Chinn & T. C. Pearson 《British journal of haematology》1997,98(1):103-107
Detection of non-palpable early splenic enlargement may aid diagnosis of primary polycythaemia (PP) and primary thrombocythaemia (PT). In this study linear spleen sizing by ultrasound has been compared with spleen volume estimation by single photon emission computerized tomography (SPECT) in 26 patients. Spleen length by ultrasound correlated well with SPECT volume estimation.
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
69.
K. Reynen U. Röber W.G. Daniel R. Henßge S. Schüler 《Clinical research in cardiology》1998,87(5):331-335
Zusammenfassung Zahlen zur H?ufigkeit von Herztumoren im operativen Krankengut liegen bisher für die Bundesrepublik Deutschland nicht vor.
Um einen entsprechenden überblick für das Jahr 1996 zu erhalten, wurde allen 77 herzchirurgischen Zentren der Bundesrepublik
Deutschland ein standardisierter Fragebogen zugesandt.
Daten von 65 der 77 Herzzentren (=84%) waren schlie?lich verfügbar: 187 Patienten waren wegen Myxomen, lediglich 44 wegen
nichtmyxomat?sen Tumoren, davon 28 wegen malignen prim?ren oder sekund?ren Herztumoren, operiert worden. Im Jahr 1996 waren
somit 0,32% (231/72 763) der Eingriffe mit Herz-Lungen-Maschine (erfa?t 72 763 von insgesamt 87 372) wegen eines Herztumors
vorgenommen worden. Ausgehend von diesen operativen Daten liegt die Inzidenz ausschlie?lich der prim?ren Tumoren des Herzens
zumindest bei 3 Tumoren pro 1 Million Einwohner pro Jahr (253 Tumoren/81,814 Millionen Einwohner). Wenn auch kleine Tumoren
asymptomatisch und unentdeckt bleiben k?nnen, wird heute doch die Mehrzahl prim?rer kardialer Tumoren durch Echokardiographie,
Computer- und Kernspintomographie bereits zu Lebzeiten des Patienten diagnostiziert, und diese Patienten werden in aller Regel
einer Operation zugeführt.
Somit werden gut 0,3% aller Eingriffe mit Herz-Lungen-Maschine in Deutschland wegen Herztumoren durchgeführt, wobei es sich
weit überwiegend um Myxome handelt.
Eingegangen: 23. September 1997, Akzeptiert: 11. Februar 1998 相似文献
70.
本实验制作不同程度心肌缺血的动物模型,以声处理5%人血白蛋白为超声造影剂进行心肌灌注造影,探讨MCE时间-强度曲线各指标与心肌缺血程度间的关系。结果表明:心肌显影的峰值强度和曲线下面积均与缺血程度呈显著负相关(相关系数分别为r=-0.98,P值<0.005;r=-0.94,P值<0.05),且能区分轻度、中度和重度三种程度的心肌缺血;而三项时间指标与心肌缺血程度间未发现显著性差异。本实验的初步结果表明,MCE是一项活体评估局部心肌血流灌注的有效方法。 相似文献