结直肠癌病变部位与单体位扫描的关系在减少CT剂量中的对照研究

目的探讨不同部位结直肠癌病变显示清晰程度与扫描体位(仰卧位和俯卧位)的关系,为减少CT结肠成像(CT colonography,CTC)检查剂量、选择最佳单体位扫描提供理论依据。资料与方法对52例结直肠癌患者术前行CTC,均行仰卧位及俯卧位检查,将CTC结果与纤维肠镜和手术病理对照。结果52例结直肠癌中,病变位于直肠27例,肛管3例,乙状结肠9例,降结肠3例,横结肠4例,升结肠6例,均为单发病灶。病变位于直肠25例(92.59%)(χ2=32.72,P<0.05),位于乙状结肠9例(100%)(χ2=8.42,P<0.05)。俯卧位上肠管充气明显,病变显示清晰,优于仰卧位,差异具有统计学意义;病变位于横结肠4例(100%)(χ2=4.5,P<0.05),仰卧位肠管充气明显,病变显示清晰,优于俯卧位,差异具有统计学意义。升降结肠病变在仰卧位(9/9)及俯卧位(9/9)上肠管充气效果相同,均显示清晰,差异无统计学意义;肛管癌在仰卧位(0/3)及俯卧位(0/3)上均显示欠佳,由于病例数少,差异无统计学意义。CT显示浆膜面受侵的诊断正确率为85.71%,CT诊断淋巴结转移的假阳性率为25%,假阴性率为12.90%,远...     

结肠充气螺旋CT扫描评估结肠癌:放射-病理对照

为了确定结肠充气螺旋CT扫描在结肠癌分期中的准确性,作者对已知或疑为结肠病变的52例病人(男27例,女25例,年龄40～88岁)做了此项检查。检查前一天清洁结肠,扫描前即刻静注Buscopan 20mg,然后通过钡灌肠管或Foley氏管注气扩张结肠,使直肠、乙状结肠直径至少为3cm,降结肠4cm以上,升结肠和横结肠5cm以上。病人仰卧位照取定位片,扫描范围从耻骨联合至膈肌,层厚5mm,螺距1.5,三维工作站重建间隔2.5mm。12例以3ml/s速     

改良式手术治疗先天性巨结肠31例

先天性巨结肠根治手术方法颇多,均有一定的并发症。1990年以来,我们在结肠切除、盆腔内低位直肠-结肠吻合术(Rehbin)的基础上,同时行后位内括约肌纵向切断术,治疗小儿先天性巨结肠31例,取得满意疗效。1　临床资料1.1　一般情况　本组31例,男22例,女9例;年龄2～8岁。出生后均不能自己大便,须扩肛或灌肠排便。1.2　X线钡灌肠造影检查　通过钡充盈和排泄过程,可以动态观察各段肠管的形态及蠕动功能。主要表现为:扩张段口径与狭窄段口经呈明显差异,直肠、乙状结肠远端细狭,乙状结肠近端及降结肠明显扩张;有时移行段也能清晰显影,呈漏斗状。扩张…     

低剂量CT结肠成像的图像质量与辐射剂量评价

目的评估低剂量CT结肠成像的图像质量,并统计其辐射剂量,探讨其临床应用价值。资料与方法对51例患者进行低剂量CT结肠成像。俯卧位扫描条件为120kV,30mAs;仰卧位扫描条件为120kV,50mAs。由两名医师盲法判定两种体位CT结肠成像的图像质量。记录每例患者接受CT低剂量结肠成像时的容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP),并估算出有效剂量。结果结肠的CT图像质量评分:仰卧位与俯卧位各评分点之间均无显著性差异(P>0.05),其图像质量较高;肠外实质器官的CT图像质量评分:仰卧位图像可以满足诊断需要,而俯卧位图像影响诊断和观察,两者各评分点之间有显著性差异(P<0.05)。辐射剂量测定:低剂量CT结肠成像的CTDIvol及DLP比常规腹部扫描降低了约70.7%。结论低剂量CT结肠成像降低了患者的辐射剂量,结肠及腹部实质器官的图像质量满足诊断要求。     

多层螺旋CT在诊断结肠病变中的应用

目的；研究MSCT结肠检查4种后处理成像技术及其临床应用价值。方法：应用MSCT对37例患行一次屏气全结肠段容积扫描，包括结肠癌14例，结肠息肉16例，慢性结肠炎5例，结节型回盲辨误诊息肉1例，结肠多发憩室1例。除1例憩室外，均经手术和／或纤维结肠镜检查活检病理证实。在工作站获取多平面重建（MPR）、CT仿真结肠镜（CTVC）、三维表面遮盖显示（3D－SSD）、四维透明显示（4D－Raysum)4种后处理图像并进行比较。结果：CTVC有利于息肉的检出，本组显示最小息肉直径为3.5mm，与纤维内镜比较息肉的总检出率为86．5％。MPR能直观反映息肉和癌肿处理壁及肠周侵犯情况，对癌肿肠周侵犯判断正确率达100％，同时有助于结肠正常结构、粪块及肿瘤鉴别。4D－Raysum较3D－SSD、MPR及CTVC在显示癌肿长度上占优势，判断正确率可达100％，亦优于钡灌肠检查。结论：MPR、CTVC、3D－SSD、4D－Raysum检查结肠病变临床应用价值各有不同，4种后处理技术的结合更有利于结肠病变的诊断。     

不同体位呼气相螺旋CT扫描对造血干细胞移植后肺部气体潴留诊断的价值

目的 探讨不同体位呼气相薄层MSCT对异基因造血干细胞移植(allo-HSCT)后肺部气体潴留诊断的价值.方法 对31例allo-HSCT后患者行低剂量呼气相仰卧位、俯卧位肺部MSCT扫描,检查患者肺部有无气体潴留病灶,利用GE 工作站测定气体潴留区域(呼气相肺部CT值≤-700 HU)占全肺体积百分比,并进行评分,得出体积分数.对不同体位病灶检出率用McNemar检验,对测得的体积分数进行秩和检验.结果 仰卧位扫描发现8例气体潴留阳性(25.8％);俯卧位扫描阳性15例(48.4％),其中双体位均示阳性7例,仰、俯2种体位的阳性检出率差异有统计学意义(x2 =4.00,P=0.039);2种体位测得体积分数仰卧位得分13分,俯卧位得分21分,差异有统计学意义(Z=-3.37,P=0.001),俯卧位对气体潴留敏感度较高.结论 allo-HSCT后临床上出现慢性排异反应患者进行呼气相薄层MSCT肺部检查,应加扫俯卧位,不仅可以更敏感地发现双肺下叶前段气体潴留病灶,并且可以初步评估气体潴留的严重程度,为临床早期诊断和早期治疗提供依据.     

CT结肠成像:运用东莨菪碱松弛肠道

行CT结肠成像时运用药物松弛肠道使得肠腔得以充分地扩张,有助于提高图像质量:在肠腔充分扩张的基础上,可以评估肠壁腔面的情况,更确切地说能检出结肠、直肠多发息肉。Ro-galla等回顾性对比研究,在仰卧位CT结肠检查时分别行东莨菪碱和胰高血糖素药物干预下检出的萎陷肠段数目是     

小儿先天性巨结肠不典型X线征群对诊断的意义

目的：探讨新生儿先天性巨结肠不典型X线征的诊断价值。方法：搜集经手术和病理证实的34例具有不典型X线征的先天性巨结肠新生儿．对他们的腹部平片和钡剂灌肠结果进行研究。结果：新生儿先天性巨结肠腹部平片多表现为结肠低位梗阻和肠淤胀(23例，占67．6％)，少部分表现为小肠低位梗阻(9例，占26．5％)。直肠下端局限性切迹(13例)，直肠和下段乙状结肠的螺旋形或不规则大锯齿状收缩(8例)，24h随访钡剂潴留(18例)．结肠炎表现(11例)．为钡剂灌肠不典型征群。结论：直肠下端局限性切迹和直肠下段乙状结肠的螺旋形或不规则大锯齿状收缩以及24h随访钡剂潴留、结肠炎表现征象对于新生儿不典型先天巨结肠的诊断价值较大。     

多发畸形1例报告

患者女性26岁，未婚。自幼两个肛门、10岁时曾去医院检查，诊断为直肠阴道瘘，建议手术治疗，至止26岁时来院检查治疗，行肠镜检查，结肠在26cm内均未发现异常，即给予钡剂灌肠，其直肠，乙状结肠，降结肠，横结肠及升结肠均未发现异常。     

CT仿真结肠镜检查的临床应用价值研究

目的　研究CT仿真结肠镜 (CTvirtualcolonoscopy ,CTVC)检查的临床应用价值。材料与方法　应用螺旋CT对 10 2例患者行容积扫描 ,包括结、直肠癌 6 4例 ,结、直肠息肉 2 6例 ,溃疡性结肠炎、慢性结肠炎各 3例 ,脂肪瘤 2例 ,恶性非霍奇金淋巴瘤、脾恶性非霍奇金淋巴瘤侵犯结肠、类癌和子宫内膜异位各 1例 ,憩室 7个病灶。除憩室外 ,均经手术和 /或常规结肠镜 (conventionalcolonoscopy ,CC)检查活检病理证实。在工作站应用Navigator软件获取CTVC图像。结果　CTVC能够显示 >4.0mm的癌结节和溃疡、>3.4mm的息肉 ,癌肿分型判断正确率为 92 .2 % ;结合原始横轴面、2D多平面重建 (multiplanarreformation ,MPR)、表面遮盖显示(shadedsurfacedisplay ,SSD)和透明显示 (Raysum)图像 ,有助于病变定位、定性。结论　CTVC是一种有效的检查方法 ,可为结、直肠病变的检查开创新的途径。     

The value of prone imaging in CT pneumocolon

AIM: To evaluate the value of prone imaging in computed tomography pneumocolon. MATERIALS AND METHODS: In the U.K., patients commonly undergo computed tomography (CT) pneumocolon in the supine position alone. A prospective analysis of both supine and prone CT images was performed. The degree of distension and the presence/absence of fluid/faecal residue were documented. RESULTS: Twenty-five patients were examined in total. In all cases, all five segments of the colon were well visualized on combined assessment of supine/prone images. Diagnostic distension was obtained in all five segments of the bowel in 69% of cases in the prone position, but in only 24% of patients in the supine position. The rectum and sigmoid colon were well distended in 100 and 88%, respectively, on prone CT, but in only 58 and 35% of cases, respectively, on supine CT. Problems encountered by fluid/faecal residue were eliminated on prone CT. CONCLUSION: Adjunctive prone pelvic CT should be performed in all patients undergoing CT pneumocolon unless the supine images can be fully reviewed and shown to be satisfactory before the patient leaves the CT department. If a single positional sequence is to be performed, then prone CT is the position of choice.     

Bowel wall visualisation at CT colonography

Purpose: To evaluate the quality of bowel wall visualisation at CT colonography and the impact of examination in the supine and prone positions.Material and Methods: After bowel preparation, 111 patients underwent CT colonography. Air distension, degree of fluid redistribution with change in body position (supine and prone), influence of residual stool on bowel wall assessability, and quality of overall colon visualisation were evaluated using scales.Results: Thirty of 110 patients (27%) had complete overall visualisation of the colon wall and 52 (47%) had subtotal visualisation of a limited part of the colon. The entire colon was more often air-filled in the prone position (46%) than in the supine position (18%). Joint review of supine and prone data showed that for all colon segments, except the sigmoid (86%), ≥95% of the patients had complete air filling. All patients had residual fluid. In 75% to 99%, depending on segment, fluid did not interfere with the bowel wall visualisation in the combined evaluation of supine and prone data sets. Thirty-one patients had residual stool with potential negative influence on polyp detection.Conclusions: The colon wall was completely, or almost completely, visualised in 75% of the patients, and examination in the supine and prone positions was necessary for complete visualisation.     

CT结肠造影对结肠癌及息肉的应用价值

目的 比较研究螺旋CT结肠造影对结肠癌及息肉的临床应用价值。方法 58例结肠癌及结肠息肉的CT原始图像资料传至工作站进行后处理，获取CT仿真结肠镜（CT virtual colonoscopy,CTVC)，多平面重建（mulitiplanar reformation,MPR)＋轴位，表面遮盖显示（shaded surface display,SSD）＋透明显示（Raysum)图像，所有病例均经手术病理和（或）电子结肠镜（electronic colonoscopy,EC)活检证实。结果 轴位＋MPR，CTVC，SSD＋Raysum对结肠癌分型的正确判断率分别为71.74%,89.13%和58.70%，对结肠癌环周侵犯程度的正确判断率为100％，82．61％和73．91％，肿块对肠管侵犯的长度的正确判断率为80．43％，60．87％和100％；对结肠息肉的检出率分别为65．15％，75．76％和51．52％。结论 轴位＋MPR能较准确判断肿块周侵犯的程度，CTVC能准确判断肿块的分型，SSD＋Raysum有助于准确判断肿块的长度；以上多种方法综合起来评价更有助于全面，细致地显示病变情况，尤其可提高息肉的检出率，从而为临床提供更多的病变信息。     

A comparative study of degree of colorectal distention with manual air insufflation or automated CO2 insufflation at CT colonography as a preoperative examination

Objectives

The purpose of this study was to compare the degree of colorectal distention between manual insufflation using room air and automatic insufflation using carbon dioxide for computed tomography colonography performed as a preoperative examination for patients with colon cancer.

Materials and methods

Participants comprised 200 patients who underwent computed tomography colonography immediately after colonoscopy from October 2011–2012. The first 100 patients were examined using manual insufflation, and the remaining 100 patients were examined using automated insufflation. Two radiologists independently assessed colorectal distention using a 4-point scale in six segments: cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. Mean scores of the two radiologists were used to analyze whether any differences existed between techniques in terms of the degree of distention per segment.

Results

Mean distention values for the colonic lumen were better using the automated technique than with the manual technique in both positions (p < 0.05). In segments, distention was significantly better using the automated technique than using the manual technique in the sigmoid and descending colon for prone patients, and in all segments for supine patients.

Conclusions

Automated carbon dioxide insufflation offered significantly improved colorectal distention scores compared to manual room air insufflation.     

Clinical validation of high-resolution fast spin-echo MR colonography after colon distention with air

To evaluate the feasibility of MR colonography (MRC) with air using two-dimensional (2D) T1-weighted fast spin-echo (T1wFSE) in patients scheduled for conventional colonoscopy (CC) after classic bowel preparation, and assess the ability of the technique to detect colonic lesions. The distention was sufficient for diagnosis, and the technique provided adequate delineation of the wall in the majority of segments. Residual fluid obscured the wall in different segments, especially in the ascending and descending colon (supine position) and in the cecum, transverse, and sigmoid colon (prone position). These findings were consistent with CT colonography. MRC visualized three lesions, missed one lesion >10 mm, visualized none of four lesions <5 mm, and yielded one false-positive lesion (5-10 mm). Missed lesions can be due to inconsistency in the slice positions between consecutive breath-holds, which is inherent to the multishot technique. Residual fluid may have obscured the smaller lesions. The shortcomings of the technique are limited coverage and signal drop-off at the borders of the field of view (FOV). Before multishot 2D T1wFSE colonography can become a valid screening method, improved patient preparation and a more practical technique are needed.     

CT colonography: value of scanning in both the supine and prone positions

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of CT colonography when patients were imaged in both the supine and prone positions. We evaluated whether imaging in two positions decreased the number of collapsed colonic segments and increased sensitivity for polyp detection. MATERIALS AND METHODS: Twenty-three patients underwent CT colonography in both the supine and prone positions. Colonic distention for each of the 46 scans was graded. Adequacy of distention for either position alone was compared with that of the combination of the two positions. Polyp data revealed by colonoscopy were reviewed, and the CT data were then retrospectively reviewed for polyp detection. RESULTS: When each scan was considered alone without benefit of the scan obtained in the opposite position, 27 (58.7%) of 46 scans showed inadequate distention. When scans obtained in both positions were considered together, 20 (87.0%) of 23 patients had adequate distention with the grading system used. However, this value increased to 23 (100%) of 23 patients when the reasons for inadequate distention in the three patients were considered. Of the 27 polyps detected with colonoscopy, 21 (77.8%) were also detected retrospectively with CT colonography. Colonoscopy showed 20 polyps that were 5 mm or larger; nineteen (95.0%) of these 20 polyps were also detected retrospectively with CT colonography, nine (47.4%) of which were seen in only one position. CONCLUSION: Use of both the supine and prone positions for patients undergoing CT colonography improves evaluation of the colon and increases sensitivity for polyp detection.     

Positional change in colon polyps at CT colonography

PURPOSE: To determine the frequency with which polyps change positions with respect to the bowel surface and the cause of this movement. MATERIALS AND METHODS: From December 2001 to March 2003, 113 patients underwent computed tomographic (CT) colonography prior to colonoscopy. For all confirmed polyps that were 5 mm and larger, images obtained with CT colonography were retrospectively analyzed by one author to determine if the polyp was present on both data sets or on only one data set. Retrospective evaluation of these polyps for ventral or dorsal location within the colonic lumen was performed for data sets obtained with patients in the prone and the supine position. The data sets were further reviewed by another author to determine the cause of positional change, when present. RESULTS: Twenty-six patients had a total of 49 histologically proved colorectal polyps that were 5 mm and larger. Eight of 49 colorectal polyps were depicted only on images obtained with the patient in the supine or prone position. Of the remaining 41 polyps that were depicted on images obtained with the patient in the supine and the prone position, 11 moved from a dorsal to a ventral location or vice versa relative to the colonic surface when the patient changed position. Five of these polyps were pedunculated on a stalk. Six were sessile; two were located in the sigmoid colon, two in the transverse colon, one in the ascending colon, and one in the cecum. In these cases, polyp mobility was related to positional changes of the colon in the mesentery, as opposed to true mobility of the polyp. CONCLUSION: In this series, 27% of polyps moved from a ventral location to a dorsal location relative to the colonic surface when the patient was turned from the supine to the prone position; thus, polyps appeared to be mobile. Thus, a mobile filling defect cannot be assumed to be residual fecal material at CT colonography.     

结肠CT三维成像在直肠癌术前临床应用的研究

目的 探讨结肠3DCT成像在直肠癌术前临床应用的价值。资料与方法 对35例已知直肠癌患者先后进行结肠CT仿真内镜（CTVE）和结肠镜检查,并均经手术病理证实。采用16层螺旋CT进行全结肠扫描,在独立的工作站上进行结肠的三维重建,包括表面遮盖法（SSD）和CTVE。由2名影像学医师共同阅片。结肠外CT所见主要依据临床、手术及其他影像学检查所证实。结果 35例直肠癌共36个病灶（1例有2个癌灶）,早期癌1个,进展期癌35个。进展期直肠癌中以Borrmann 2型最多见,占71．4％（25／35）;中分化癌20例,占57．1％;浸润全层者30例,占85．7％。3DCT对进展期直肠癌Borrmann分型判断的正确率达97．1％（34／35）,而结肠镜的正确率为88．6％（31／35）。两种检查方法对于直肠癌的定位均比较满意。在3DCT中,SSD像最为直观立体,便于外科术前定位分析;CITE像最利于病灶大小的测量,与结肠镜的结果基本一致,与手术结果相符。25．7％（9／35）直肠癌患者的结肠镜检查时由于肠道严重狭窄或患者情况而失败,而这些患者在CTVE检查效果比较满意,在结肠远端发现2枚息肉和1个溃疡型癌,阳性所见占33．3％（3／9）。19例患者结肠CT检查发现结肠以外病灶,占54．3％（19／35）,其中肝可疑性病灶占22．9％（8／35）。结论 结肠CT检查对于直肠癌患者的术前准确定位定性评价是有价值的,并且在补充结肠镜的不足、以及发现肠外病灶等方面也有重要临床意义。     

Morton neuroma: MR imaging in prone,supine, and upright weight-bearing body positions

PURPOSE: To assess the effect of prone, supine, and upright weight-bearing body positions on visibility, position, shape, and size of Morton neuroma during magnetic resonance (MR) imaging. MATERIALS AND METHODS: Eighteen patients with 20 Morton neuromas underwent MR imaging of the forefoot in prone (plantar flexion of the foot), supine (dorsiflexion of the foot), and upright weight-bearing positions. Visibility (3 = good, 2 = moderate, 1 = poor), position relative to the metatarsal bone, shape, and transverse diameter of Morton neuroma were assessed on transverse T1-weighted MR images. Associations between different body positions and variables of interest were calculated with Wilcoxon signed rank test, chi2 test, and paired Student t test. RESULTS: In the prone position, visibility of all 20 Morton neuromas was rated with a score of 3; visibility in the supine and weight-bearing positions was inferior (mean score, 2.4). All 20 (100%) Morton neuromas changed their position relative to the metatarsal bone between prone and supine and between prone and weight-bearing positions. When compared with the prone position, there was a difference in the shape of all 20 Morton neuromas in the weight-bearing position (P <.001). Between prone (mean transverse diameter of Morton neuroma, 8 mm) and supine (mean transverse diameter of Morton neuroma, 6 mm) positions, the transverse diameter of Morton neuroma significantly decreased by 2 mm (P =.03); between prone and weight-bearing positions, the decrease of the mean transverse diameter was also significant (difference, 2 mm; P =.03). CONCLUSION: Morton neuroma appears significantly different during MR imaging in prone, supine, or weight-bearing positions. The transverse diameter of Morton neuroma is significantly larger on images obtained in the prone position than it is on images obtained in the supine and upright weight-bearing positions. Visibility of Morton neuroma is best on MR images obtained in the prone position.     

Supine/left decubitus scanning: a valuable alternative to supine/prone scanning in CT colonography

The purpose was to evaluate supine/left decubitus as an alternative to supine/prone scanning in computed tomographic colonography (CT colonography). Fifty patients were randomised to supine/prone, another 50 to supine/left decubitus scanning. Patients were scanned using a single-slice CT scanner. The colon was divided into eight segments. Comparisons of distension, breathing artefacts, residus and polyp detection were made between the two groups as well as between the different positions. Adequate distension was found in approximately 85, 97 and 95% of segments in the supine, prone and left decubitus positions, respectively. Combined scanning increased the percentage of adequate distension to 98.5% for prone-supine and 97.7% for left decubitus-supine scanning (P<0.0005 compared to supine, P=0.001 compared to left decubitus and P=0.046 compared to prone scanning). Absence of residual material was found in approximately 62.7, 69.7 and 64% of segments in the supine, prone and left decubitus positions, respectively. Combined scanning increased this percentage to approximately 99% for both groups. No significant differences towards distension or residual material were found between combined supine-prone or supine-left decubitus scanning. In the supine-prone group, combined scanning additionally revealed four lesions and improved conspicuity in two cases of stalked polyps. In the supine-left decubitus group, combined scanning additionally revealed two lesions and improved conspicuity in one stalked polyp. There were significantly fewer breathing artefacts with left decubitus scanning than prone scanning (P=0.005). A strong positive correlation was found between breathing artefacts and the age of patients in both patient groups. Colonic distension and preparation is improved by using supine and prone or supine and left decubitus scanning in combination, with a subsequent improved polyp detection. There were no significant differences between the two scanning protocols. Prone scanning, however, is hampered by breathing artefacts, especially in the elderly. Therefore, supine-left decubitus scanning is considered a valuable alternative to supine-prone scanning for the elderly.