直肠肛管周围肌组织感染的MRI诊断

目的 分析8例直肠肛管周围肌组织感染的MRI表现,初步探讨其发病机制.方法 回顾性分析8例肛提肌和/或耻骨直肠肌、肛门外括约肌感染患者的MRI表现,初步分析其与肛管、直肠的关系.结果 1例发生于肛门外括约肌右半部,6例发生于肛门外括约肌深部以上水平,均伴发直肠肠壁炎性肿胀及肠壁外膜破口形成,其中5例破口位于直肠者,肛提肌、耻骨直肠肌均可见脓肿形成,伴或不伴肛门外括约肌深部病变;2例破口位于肛门外括约肌深部水平肛管者,耻骨直肠肌及肛门外括约肌深部形成感染灶,未见肛提肌受累及,即破口位置高者,直肠肛管周围肌组织感染灶位置亦较高.另外1例位于外括约肌肌浅部,感染灶与邻近中央间隙脓肿分界不清.结论 局部直肠或肛管感染后炎症可播及邻近肌肉组织,肛门直肠周围肌肉组织并不能阻挡肛周感染的传播.     

肛门直肠周围脓肿、肛瘘的磁共振诊断与应用价值

目的:探讨磁共振成像在肛门直肠周围脓肿、肛瘘诊断中的临床应用价值。方法:回顾性分析2008年9月~2010年3月经病理证实的58例肛门直肠周围脓肿/肛瘘患者,其中男性肛周脓肿12例,肛瘘30例,女性肛周脓肿6例,肛瘘10例。病例均于术前行常规盆腔磁共振检查,其中40例行增强检查,扫描序列包括矢状、冠状T2WI,轴位T1WI、T2WI,轴位T2脂肪抑制序列,增强轴位、矢状脂肪抑制T1WI序列。术前诊断与手术及病理结果对照。结果:58位患者,术前磁共振发现脓肿24个,瘘管40条,内口32个;4例内口及5例支瘘管漏诊。结论:磁共振检查对肛门直肠周围脓肿、肛瘘诊断及明确脓肿、肛瘘位置、数目,累及范围、瘘管走行及其与周围结构关系具有很高的应用价值。     

低位直肠癌侵犯肛提肌的MRI评价

目的通过对低位直肠癌侵犯肛提肌的MRI征象与手术对照分析,探讨直肠癌侵犯肛提肌（耻骨直肠肌、髂骨尾骨肌）的MRI表现。方法 16例低位直肠癌,经手术证实癌肿均有不同程度侵犯肛提肌,其中男11例,女5例,年龄39～75岁,平均55岁。结果本组16例肛提肌受累的低位直肠癌患者中,耻骨直肠肌及髂骨尾骨肌两者均显示同时受侵犯。在横断面观察显示受累的耻骨直肠肌周围脂肪间隙消失16例;耻骨直肠肌增粗12例;病变区域内不规则形T2信号增高9例。在冠状面观察显示受累髂骨尾骨肌不规则增粗14例;肌束不连续11例;肌束边缘呈锯齿状改变10例;肿物与髂骨尾骨肌间隙消失16例。本组16例患者中,肿物下缘与齿状线距离均小于5cm,其中小于1cm者5例,1～2cm者5例,2～3cm者4例,3～5cm者2例。4例盆腔淋巴结增大,其中包括盆壁淋巴结增大2例,直肠周围淋巴结增大2例;3例腹股沟淋巴结增大。16例患者均显示直肠肌层受累,其中10例直肠周围筋膜增厚。结论 MRI检查对低位直肠癌侵犯肛提肌具有一定的优势,其主要征象包括：a）肿物与肛提肌之间脂肪间隙模糊或消失;b）耻骨直肠肌受累以横断位显示为佳,肌束中断及T2WI信号增高为主要表现;c）髂骨尾骨肌受侵则以冠状位显示较好,肌束增粗、连续性中断及其边缘呈锯齿状为主要表现。     

肛管直肠周围脓肿磁共振成像诊断简

肛管直肠周围脓肿（肛周脓肿）为肛管和直肠周围软组织内或其周围间隙内发生的急性化脓性感染。国内将肛周脓肿一般分为肛提肌下脓肿（低位）及肛提肌上脓肿（高位）［1］，确定脓肿的位置非常重要，它已成为深部肛周脓肿治疗成败的关键［2，3］。目前肛周脓肿的术前诊断与评估主要依据肛门指诊。然而，肛门指诊不仅难确定病变涉及的范围，而且深部肛周脓肿发现率低，超声在评价肛周脓肿中的作用在不断发展，然而也存在着某些不足之处［4］；磁共振成像（MRI）检查因其能清晰显示肛周脓肿并描述肛门括约肌复合体而逐渐成为深部肛周脓肿术前诊断的金标准［5］。     

多层螺旋CT重组技术在先天性支气管肺囊肿术前评估中的价值

目的 探讨多层螺旋CT重组技术在先天性支气管肺囊肿术前评估中的价值.资料与方法 对15例先天性支气管肺囊肿患者采用多层螺旋CT进行薄层扫描,并在工作站上对扫描数据进行支气管和肺的表面重组(SSD)和多平面重组(MPR),明确诊断以后,协同胸心外科医师根据肺部病灶的形态、部位、大小、数目、密度、范围、周边解剖关系、继发病变、肺功能可能受损情况等,从影像学角度评价手术切除的可行性,选择手术适应证.结果 15例先天性支气管肺囊肿中单发13例,多发2例;右肺11例.左肺4例.含气囊肿7例;含液囊肿3例;含气液混合囊肿5例.5例含气液混合囊肿与7例含气囊肿用支气管和肺SSD、MPR重组方式均能很好显示,3例含液囊肿则用MPR重组方式能良好地显示.15例患者经术前CT明确诊断和评估,实际手术治疗12例,成功切除11例.4例行单纯囊肿摘除术,6例行肺楔形切除术,1例行肺叶切除术,病灶均彻底切除.切除标本术后经病理证实.手术、病理情况与术前CT影像学评估一致.结论 多层螺旋CT的SSD、MPR重组技术是先天性支气管肺囊肿术前诊断的最佳影像学检查方法,并且在外科术前评估中具有重要意义.     

CT直接冠状面扫描对直肠癌诊断和分期的价值

目的：探讨CT直接冠状面扫描在直肠癌诊断和分期中的价值。材料和方法：对13例直肠病变的病例行横断面加直接冠状面扫描。在直接冠状面扫描时，应尽量提高KV及mA，并对所获图像进行后处理。结果：本组13例，直肠癌11例，腺病及炎性改变各1例。总的诊断符合率为84．6％，其中按照Duke改良法分期，Ⅰ期诊断符合率为50％，Ⅱ期为67％，Ⅲ期及Ⅳ期为100％。CT显示直肠病灶的关键在于充分扩张的肠腔和肠腔内外良好对比。CT直接冠状面扫描可以准确显示病灶范围及与周围脏器的关系，并可以直接测量肿块距肛缘的距离，浆膜层和肠周脂肪受侵犯时表现为索条状或片状致密影，其中肠壁外结节影为浆膜层受累的可靠征象。结论：CT直接冠状面扫描结合横断面扫描对直肠癌诊断和术前分期有帮助。     

会阴部的CT检查

CT对盆腔恶性肿瘤的诊断价值已被确认,但对耻骨联合以远的会阴部的CT扫描的重要性尚未受到重视,有关会阴部的CT解剖也还没有详细的报导。本文作者报告了20例正常人和2例尸体的会阴部横断面、矢状面和冠状面CT扫描的正常解剖以及22例盆腔会阴部病变的CT表现。在横断面CT扫描上可以显示直肠、闭孔内肌、闭孔外肌、前列腺、前列腺段尿道,女性的阴     

后盆底肛周感染的MRI定位初探

目的基于最新的肛部MRI解剖研究成果,探索一种后盆底肛周感染的新定位系统。方法肛部被分为4区。A区位于肛提肌的内侧和上方;B区位于肛提肌的外侧和下方;C区位于中央间隙(肛门平滑肌和肛门外括约肌之间的脂肪间隙),此处肛提肌尾端变成了一系列腱索,导致A区和B区在C区直接连通;S区为肛管黏膜下间隙。依据脓肿和肛瘘的位置,92例患者被计数和分类。结果 92例患者中共发现93处脓肿和肛瘘病灶,与C区有关的感染灶71处,与C区无关者22处,C区通过肌间隙扩散65处,其中与B区通过肛提肌外侧间隙及肛门外括约肌深部、浅部间肌间隙沟通者60处,占92.3%,C区向上通过肛提肌内侧间隙与A区沟通者5处,占7.7%,C区感染灶通过外括约肌和/或耻骨直肠肌累及B区者14例。结论使用全部肛门肌肉和肛周间隙作为界标,可以为外科医生做出一个更精确的肛周感染的定位,指导制定更合理的治疗方案。     

眼眶副鼻窦区多层螺旋CT扫描冠状面重建与直接冠状面扫描图像的对比研究

目的分析眼眶、副鼻窦多层螺旋CT扫描MPR冠状面重建与直接冠状面扫描图像,探讨冠状面重建能否代替直接冠状面扫描。方法使用GE lightspeed p lus 4层面螺旋CT扫描仪对116例眼眶、副鼻窦病变患者进行扫描,在横断面图像基础上进行MPR重建。由资深专家对重建冠状面图像与直接冠状面扫描图像进行评价和对比分析。结果116例中,62例同时行MPR重建对眼眶、副鼻窦解剖结构及病变的显示与直接冠状面扫描图像相似,图像质量均为Ⅰ级。54例不能进行直接冠状面扫描者,冠状面重建多数也能达到诊断效果(Ⅰ级32例,Ⅱ级3例)。结论多层螺旋CT扫描对眼眶、副鼻窦的MPR冠状面重建图像能够代替直接冠状面扫描。     

先天性外中耳畸形的螺旋CT与手术对照观察

目的进一步提高螺旋CT及后处理技术诊断外中耳畸形的水平。资料与方法对22例(24耳)经手术治疗的先天性外中耳畸形病例,术前采用螺旋CT高分辨扫描,将原始扫描数据密集重组后进行多平面重组(MPR)(轴面、冠状面、斜轴面、斜冠状面)、曲面重组(CPR)及仿真内镜容积重组(VR)成像,与手术所见进行详细对照观察。结果手术治疗24耳,外耳道狭窄1耳,骨性闭锁18耳,膜性闭锁3耳。鼓室腔狭小12耳。锤骨畸形或缺如23耳,其中1耳CT见细小锤骨,而手术为缺如。砧骨缺如4耳,砧骨畸形16耳,其中有2耳手术见砧骨长脚长、砧骨粗大,而CT表现基本正常。镫骨细小畸形6耳,其他畸形7耳,镫骨缺如5耳;砧锤关节融合畸形14耳,轻度变形1耳,缺如4耳;砧镫关节融合1耳,不连5耳,缺如7耳;卵圆窗骨性封闭8耳,上述CT所见均与手术相符。手术见3耳圆窗骨性封闭,其中1耳CT表现正常。手术有3耳未见咽鼓管开口,其中1耳CT表现正常。手术见面神经管前位8耳,其中1耳CT表现正常。结论螺旋CT高分辨扫描及其多种后处理成像综合观察,多数可以反映外中耳畸形情况,有利于指导手术方案的制定。     

CT imaging with fistulography for perianal fistula: does it really help the surgeon?

ObjectiveTo prospectively evaluate the relative accuracy of computed tomography (CT) fistulography for preoperative assessment of fistula in ano.Materials and MethodsEthical committee approval and informed consent were obtained. A total of 22 patients (15 male and 7 female, age 21–58 years) who were suspected of having fistula in ano underwent preoperative CT fistulography (CTF). The CT images of 0.6 mm were obtained respectively before and after fistulography; contrast-enhanced CT scan was also performed in 22 patients. CTF images were evaluated by two expert radiologists to assess the fistulas in the following respects: (a) the volume-rendered imaging; (b) the extensions of active inflammatory tissue; (c) the internal opening and external opening; (d) the hidden areas of tract or abscess; and (e) the deep abscess adjacent to fistula. CT findings in 18 patients were compared with surgical findings or exam under anesthesia.ResultsThe CTF findings in 18 cases were basically in accordance with the surgical findings and/or examination findings under anesthesia. Both coronal and transverse planes were useful in assessing the location and direction of tracts or abscesses. Complicated spatial information within the perianal soft tissue about the fistula with secondary ramifications or abscesses can be easily demonstrated to the surgeons. Contrast-enhanced images were useful in assessing the inflammatory lesion activity and infiltrated area.ConclusionCTF exquisitely depicts the perianal anatomy and shows the fistulous tracks with their associated ramifications, enables selection of the most appropriate surgical treatment, and therefore minimizes all chances of recurrence.     

256层螺旋CT轴位与冠状位重建对窦口-鼻道复合体正常解剖及变异的对比观察

目的：探讨多层螺旋CT（MSCT）轴位和冠状位重建对窦口-鼻道复合体（OMC）区域的正常解剖结构和变异显示能力及差异。方法：利用32例健康体检者和23例因非鼻及副鼻窦疾病而行头颈部CT扫描者,常规扫描后进行轴位和冠状位标准重建,分别对比观察OMC区域的正常解剖结构和变异及显示能力。结果：轴位和冠状位重建图像对双侧额窦开口、中鼻甲和中鼻道的显示能力无明显差异。但轴位图像在显示筛漏斗、前中组筛窦、上颌窦开口及钩突等的显示能力明显较冠状位差。结论：对OMC区域的正常结构和变异的显示冠状位明显优于轴位,冠状位重建可以代替冠状位扫描,以消除冠状位扫描给患者带来的不便。     

Role of coronal oblique reconstruction as a complement to CT study of the temporal bone: normal anatomy

PURPOSE: The purpose of this study was to demonstrate the usefulness of coronal oblique multiplanar reconstruction computed tomography (MPR CT) reformation parallel to the basal turn of the cochlea in the evaluation of the retrotympanum and hypotympanum to complete the standard CT examination of the temporal bone obtained with axial and coronal images. MATERIALS AND METHODS: We studied 30 patients aged 18-79 years for a total of 60 normal petrous pyramids. All examinations were performed on a multislice CT (MSCT) scanner (Sensation 16, Siemens, Erlangen, Germany) with axial volumetric acquisition and completed with reformations of coronal and coronal-oblique images. MSCT scan parameters for axial acquisition were set as follows: 0.75-mm scan collimation, FOV 300 mm, 170 mAs. Axial images were reconstructed at 0.7-mm thickness and with a reconstruction increment of 0.5 mm using a high-resolution bone algorithm. RESULTS: Coronal oblique MPR CT reformations provided additional information with respect to standard CT images in all cases. In particular, they enabled measurement of the craniocaudal and laterolateral diameters of the sinus tympani. In all cases, there was optimal visualisation of the ponticulus and subiculum. Analysis of the pyramidal eminence was improved thanks to its visualisation in profile. Moreover, we obtained an optimal representation of the hypotympanum, which was always exhaustively explored with only one reconstruction. Finally, in all cases, it was possible to identify the facial nerve canal and main vascular structures and to measure the distance between these and the sinus tympani, pyramidal eminence and hypotympanum. The coronal oblique CT reformation was of no advantage in the evaluation of the fossa of the oval window and the niche of the round window. CONCLUSIONS: Coronal oblique MPR CT reformation should not be considered an alternative to the standard CT examination, but it can represent a valid integration to provide additional information on particularly crucial districts characterised by frequent involvement of inflammatory and/or expansile disease and because of their difficult endoscopic approach. Moreover, it can represent a meaningful aid to optimise surgical planning thanks to its different perspectives of observation.     

Comparison of quality of multiplanar reconstructions and direct coronal multidetector CT scans of the lung

OBJECTIVE: The purpose of this study was to compare the quality of coronal multiplanar reconstructions with the quality of direct coronal thin-section multidetector CT (MDCT) scans. MATERIALS AND METHODS: Axial multidetector CT (MDCT) scans were obtained through the entire lung in 10 normal autopsy lung specimens using an MDCT scanner. Four protocols were used: 0.5-mm collimation with a 0.5-mm reconstruction interval; 0.5-mm collimation with a 0.3-mm reconstruction interval; 1-mm collimation with a 0.5-mm reconstruction interval; and 2-mm collimation with a 1-mm reconstruction interval. Multiplanar reconstruction images with 0.5-mm slice thickness were obtained from the four types of data sets. Direct coronal thin-section CT of the same 10 autopsy lung specimens was performed using 0.5-mm scan collimation, a 0.3-mm reconstruction interval, a 25.6-cm field of view, and a 512 x 512 matrix. Two independent observers compared the image quality of each of the four coronal multiplanar reconstruction sets with that of direct coronal thin-section CT scans. The observers analyzed visualization of anatomic features and artifacts. RESULTS: The total image quality of the multiplanar reconstructions obtained from 0.5-mm collimation data with or without 0.3-mm overlapping reconstruction was equal to that of direct coronal thin-section CT scans in all 20 interpretations. The image quality of multiplanar reconstruction images from 0.5-mm collimation data either with or without overlapping reconstruction was superior to multiplanar reconstruction images obtained from 1- or 2-mm collimation scans (p < 0.01, Fisher's exact test). Stairstep artifacts in multiplanar reconstructions using 0.5-mm collimation without overlapping reconstruction were equal to those with overlapping reconstruction and were fewer than those on 1- or 2-mm collimation (p < 0.01, Mann-Whitney U test). CONCLUSION: The image quality of coronal multiplanar reconstructions from isotropic voxel data obtained using 0.5-mm collimation, with or without overlapping reconstruction, is similar to that of direct coronal thin-section CT scans.     

鼻咽癌颅底骨破坏的CT特征及与p53蛋白的关系

目的：探讨鼻咽癌颅底骨质破坏的CT特征及与p53蛋白表达的关系。方法：经病理证实的鼻咽癌患者150例,其中颅底骨质破坏48例。12例患者行鼻咽横轴面CT扫描,其中30例同时行冠状面CT扫描。30例行薄层CT扫描及多平面重组。应用免疫组化SABC法检测所有病例中p53蛋白的表达。结果：颅底骨质破坏分3种：溶骨、成骨和混合性破坏,溶骨性破坏最多见（n=27）,破坏部位最多见于斜坡。鼻咽癌及鼻咽炎症中p53蛋白表达率的差异有极显著性意义（P〈0.001）,p53蛋白表达与鼻咽癌分化程度、颅底骨质破坏相关（P〈0.001）,溶骨破坏与成骨改变p53阳性表达率有显著差异（P〈0.05）。结论：p53蛋白表达与鼻咽癌分化程度、颅底侵犯有一定相关性。CT显示颅底骨质破坏形式可以反映p53蛋白的表达情况。     

多排螺旋CT后处理技术在胸腰椎创伤中的应用

目的:探讨多排螺旋CT(multidetector spiral CT,MSCT)图像后处理在胸腰椎创伤中的应用价值。方法:对142例有胸腰椎创伤患者行多排螺旋CT薄层扫描。采用矢状位和冠状位多平面重建(multiplanar reconstruction,MPR)和三维重建等技术后处理。结果:142例患者中,83例压缩骨折,49例爆裂骨折和10例骨折伴移位。MSCT后处理图像有助于显示骨碎片的移位和脱位的方向。结论:MSCT后处理在胸腰椎创伤的诊断及指导临床治疗方案的选择起重要作用。     

颞骨平行枕眶线多层螺旋CT扫描法及其价值

目的:探讨以平行枕眶线扫描图像为基础的常规轴位和冠状位MPR图像是否能够取代直接轴位和冠状位图像。方法:三位医师分别观察50例颞骨CT扫描图像,分析直接常规轴位(25例)、冠状位(25例)CT扫描图像和其相应的常规轴位、冠状位MPR图像显示颞骨结构的差异。结果:所有观察者均认为直接常规轴位、冠状位CT扫描图像略优于相应的轴位、冠状位MPR图像。直接轴位、冠状位CT扫描图像和相应的轴位、冠状位MPR图像的质量差异较小。结论:以平行枕眶线扫描图像为基础的常规轴位和冠状位MPR图像可取代直接轴位和冠状位扫描图像。     

螺旋CT在肝脓肿诊断中的应用

目的：评价螺旋CT、双期扫描对肝脓肿的诊断价值。方法：回顾性分析经临床或病理证实的28例肝脓肿的螺旋CT表现，所有病例均行平扫及螺旋CT双期增强扫描，其中5例经薄层重建后在工作站行表面遮盖重建(SSD)，并经切割处理，显示其冠、矢状位图像。结果：28例中，平扫表现为类圆形边缘不清楚的低密度灶17例，多房或簇状9例，不规则形1例，脓腔内积气1例。增强扫描动脉期28例均表现为病灶边缘极轻或轻度环状强化，其中有15例(53．5％)出现灶周楔形或片状一过性强化；门脉期显示簇状征9例，边缘强化10例，环靶征8例；另1例平扫为不规则形，增强扫描动脉期灶周出现明显楔形一过性强化，门脉期病灶内呈不规则强化，为较特殊表现。5例三维图像直观地显示了脓肿的立体形态和位置。结论：螺旋CT双期扫描对肝脓肿诊断有重要应用价值。动脉期的灶周楔形或片状一过性强化是肝脓肿又一重要CT表现，对诊断有指导意义。     

螺旋CT多功能重建方式对腰椎峡部裂的诊断价值

目的探讨螺旋CT(SCT)不同重建方式对腰椎峡部裂(spondyloschisis,SS)的诊断价值。方法对32例腰椎峡部裂行容积扫描后,进行表面重建(SSD)、多方位多平面重建(MPR)、改良法最大密度投影(MIP)等后处理,并由2位有经验的高年资放射科医生将获得的图像进行比较、分析。结果SSD显示SS20例22处及14例椎体滑脱,图像立体感强,解剖关系清晰;SSD结合切割(cut)及任意剖面技术,观察SS裂隙及局部骨痂、骨赘等细节,弥补了SSD只能显示感兴趣区表面改变的不足,进一步提高了对较小SS裂隙的显示率。MPR包括矢状位重建、冠状位重建、平行于椎板的左右斜位重建、沿椎管曲面重建(CPR)、平行椎弓轴线的反角度轴位重建(reversangleaxialreconstruction,RAAR)等,能显示全部32例73处SS及全部14例椎体滑脱;利用MPR的任意窗口技术可以分别显示局部骨质和软组织改变,并可对病变进行准确测量。MIP及其多角度投影技术、改良法切割技术,可以多方位、立体直观显示全部SS及其形态、走向、局部骨质改变等。结论螺旋CT多功能重建方式相互匹配是诊断SS的最佳方案,具有重要的临床应用价值。