恶性黑色素瘤的CT诊断

目的分析恶性黑色素瘤的CT表现,探讨CT诊断的价值。资料与方法回顾分析20例经手术病理证实的恶性黑色素瘤的CT表现。结果鼻腔及鼻窦中的9例肿瘤CT表现均为单侧无钙化软组织肿块,部分伴邻近结构侵犯;眼球2例表现为球内高密度占位;颅内1例为类圆形等密度灶,增强扫描强化明显;上颌骨、咽部、硬腭病灶为不规则软组织肿块;转移4例具备转移瘤特点。结论CT对恶性黑色素瘤的定性有一定限度,但可清晰显示病变范围、部位、侵犯及骨质破坏情况,对临床确定治疗方案及判断预后有重要作用。     

脉络膜恶性黑色素瘤的CT诊断

目的：探讨脉络膜恶性黑色素瘤的CT诊断价值。方法：回顾性分析27例经手术病理证实的脉络膜恶性黑色素瘤的CT表现。结果：脉络膜恶性黑色素瘤表现为宽基底扁平状7例，半球状及蘑菇状突向玻璃体腔内20例，3例有囊性变，全部病例均未见钙化，合并视网膜脱离12例。结论：CT可准确的确定肿瘤的位置、大小、形态、密度、有无球外侵犯、有无合并视网膜脱离，对指导制定治疗方案，估计预后有较大价值。     

恶性黑色素瘤38例的临床分析

目的 探讨分析恶性黑色素瘤患者的临床病理特征.方法 对1986-06~2011-06间我院收治的38例恶性黑色素瘤患者临床资料进行回顾性分析,通过对恶性黑色素瘤标本进行光学显微镜观察和免疫组化检测,对恶性黑色素瘤病理特征进行总结.结果 恶性黑色素瘤光镜下肿瘤细胞形态多样,大小不一,常出现几种类型肿瘤细胞混合存在,以上皮样细胞型、小淋巴样细胞型和梭形细胞型为主.免疫组化检测显示,肿瘤细胞VIM阳性率78.9%、S-100阳性率92.1%、HMB45阳性率97.4%.结论 采用染色和免疫组化技术分析恶性黑色素瘤多发于下肢皮肤,瘤细胞多呈上皮样细胞型等病理特征,为以后患者的诊断与针对性的治疗提供依据.     

颅内转移性恶性黑色素瘤9例临床分析

目的探讨颅内转移性恶性黑色素瘤的临床表现、诊断及手术切除效果。方法回顾性分析我科自2000年1月～2010年1月10年间手术切除的9例颅内转移性恶性黑色素瘤的临床和影像学资料,跟踪随访患者术后疗效。结果 9例患者均可见原发病灶;颅内转移灶中,7例全切,2例大部切除;随访期间所有患者死亡,生存时间最短4个月,最长23个月。结论颅内转移性恶性黑色素瘤恶性程度高,彻底切除颅内病灶可延长患者生存期,但预后仍差。     

原发鼻腔恶性黑色素瘤11例临床分析

目的观察鼻腔原发性恶性黑色素瘤的临床特点,以帮助临床诊断和治疗。方法对1992—2007年12月间诊治的鼻腔原发性恶性黑色素瘤11例临床资料进行回顾性分析。结果 11例中,肿瘤多位于鼻腔外侧壁和鼻中隔,其中中鼻道5例,鼻中隔4例,中鼻甲1例,下鼻甲1例,肿瘤呈黑色或紫褐色8例,呈结节状或菜花状,淡红色表面光滑如息肉状3例;肿瘤触之易出血。结论本病临床少见,易误诊,应与鼻腔癌、血管瘤、鼻息肉相鉴别。对鼻腔发现的黑色或紫褐色肿物,触之易出血者可作该病的临床诊断,而不必取活检,以免促进肿瘤转移。     

鼻腔及鼻窦粘膜恶性黑色素瘤的CT评价

目的 探讨鼻腔及鼻窦恶性黑色素瘤的CT诊断价值。材料与方法 回顾性分析8例经病理证实的鼻腔及鼻窦恶性黑色素瘤的CT征象。结果 8例肿瘤均无钙化,注射碘对比剂后病灶有不同程度强化。CT冠状位及轴位扫描显示肿块位于单侧鼻、窦腔6例,双侧2例;病灶中心位于鼻腔前下4例,鼻腔上部及筛窦4例;肿瘤侵犯邻近结构,包括上颌窦4例,突破筛骨纸板到眶骨膜下间隙7例,向上破坏筛骨水平板和蝶平面,并浸润相应脑膜2例。结论 CT能很好地显示窦鼻腔恶性黑色素瘤的病变部位、周围骨质破坏和邻近重要结构的侵犯。尽管这些表现缺乏特征,对该肿瘤的定性诊断帮助不大,但CT对病变的全面评价是必要且较充分的。     

肠扭转的CT表现

目的 提高螺旋CT诊断肠扭转的正确率。方法 对9例术前CT明确诊断为肠扭转，并经手术证实病例的CT资料进行分析。主要重组方法有多平面重组法（MPR）及滑动薄层块最大强度投影法（STS-MIP）。结果 9例肠扭转诊断均正确，主要征象有肠管的“漩涡征”（6例）和血管的“漩涡征”（9例）、“靶环征”（2例）、“鸟喙征”（6例）。结论 肠系膜血管的“漩涡征”是诊断肠扭转的特异性征象，“靶环征”及肠壁强化减弱、腹水是提示绞窄性梗阻的可靠征象。螺旋CT扫描及重绢对肠扭转的诊断具有莺要价值。     

原发性颅脑恶性淋巴瘤的CT和MRI表现

目的探讨颅脑原发性恶性淋巴瘤的CT和MRI表现特征。方法收集经病理证实颅脑原发性恶性淋巴瘤9例,MRI平扫和增强,CT平扫和增强,分析病灶的影像表现。结果 9例中单发6例,多发3例,共检出14个病灶,11个病灶位于中线两旁的深部脑组织内,3个病灶位于脑实质表面,7个病灶呈结节状或团块状,病灶周围水肿中到重度,占位效应较明显。CT平扫病灶全均表现为稍高密度,6例增强扫描病灶呈明显强化。MRI平扫病灶T1WI呈等、低信号,T2WI以高信号多见,增强时实质部分明显均匀强化。结论颅脑原发性恶性淋巴瘤CT、MRI表现具有一定特征性,为临床治疗方案的选择提供重要依据。     

Helical CT signs in the diagnosis of intestinal ischemia in small-bowel obstruction

OBJECTIVE: The purpose of our study was to determine prospectively the value of helical CT and of various signs of ischemia in the context of acute bowel obstruction. SUBJECTS AND METHODS: All patients seen over a 3-year period with a CT diagnosis of small-bowel obstruction were included. There were 144 examinations in 142 patients. Images were interpreted prospectively with consensus by a fellow and an experienced gastrointestinal radiologist. Attention was focused on the presence of the following signs of strangulation and ischemia: reduced enhancement of the small-bowel wall, mural thickening, mesenteric fluid, congestion of small mesenteric veins, and ascites. A diagnosis of ischemia was made if enhancement of the bowel wall was reduced or if at least two of the other signs were found. Results were correlated with surgical findings in 73 cases and clinical follow-up in 71 cases. RESULTS: A diagnosis of ischemia was made at surgery in 24 patients. CT diagnosis was correct in 23 patients (96% sensitivity). There were nine false-positive diagnoses (93% specificity). The negative predictive value of CT was 99%. Reduced enhancement of the bowel wall had a sensitivity of 48% and specificity of 100%, mural thickening had a sensitivity of 38% and specificity of 78%, mesenteric fluid had a sensitivity of 88% and specificity of 90%, congestion of mesenteric veins had a sensitivity of 58% and specificity of 79%, and ascites had a sensitivity of 75% and specificity of 76%. CONCLUSION: Helical CT is a highly sensitive method to diagnose or rule out intestinal ischemia in the context of acute small-bowel obstruction.     

PET/CT in malignant melanoma: contrast-enhanced CT versus plain low-dose CT

Purpose  

The aim of this study was to evaluate the diagnostic value of contrast-enhanced CT (CECT) versus non-enhanced low-dose CT (NECT) in the staging of advanced malignant melanoma with ¹⁸F-fluordeoxyglucose (FDG) positron emission tomography (PET)/CT.     

Closed-loop and strangulating intestinal obstruction: CT signs.

In 19 patients with closed-loop intestinal obstruction, including 16 patients with strangulating obstruction, the findings at examination with computed tomography (CT) were retrospectively correlated with the surgical and pathologic findings and evaluated by two radiologists. Signs of closed-loop obstruction, present in 15 patients, were associated with the configuration of the incarcerated loop of small bowel, abnormalities detected at the site of obstruction, or both. These abnormalities were the following: a U-shaped, distended, fluid-filled bowel loop; the whirl sign; the beak sign; a triangular loop; two adjacent collapsed loops of bowel at the site of obstruction; or all of these. CT signs of strangulation, seen in 10 of the 16 patients with ischemic or infarcted bowel, were associated with the appearance of the bowel wall (thickening, high attenuation, and the target sign), abnormalities in the attached mesentery, or both. In mechanical obstruction of the small bowel, detection of ischemic changes in the bowel wall or mesentery with CT indicates strangulation. Absence of CT findings of ischemia or infarction does not rule out strangulation.     

Primary malignant melanoma of the rectum: CT findings in eight patients

PURPOSE: To retrospectively evaluate computed tomographic (CT) findings in patients with pathologically proved primary malignant melanoma of the rectum. MATERIALS AND METHODS: CT scans of eight patients (three men and five women; age range, 38-74 years; mean age, 62 years) with histologically proved primary rectal malignant melanomas were retrospectively evaluated by two radiologists in consensus. Scans were evaluated for the involved site, approximate size and morphologic appearance of the primary mass, degree of perirectal infiltration, and presence or absence of lymphadenopathy, bowel obstruction, and distant metastases. RESULTS: All of the tumors were located in the distal rectum just above the anal verge. The approximate average sizes of the tumors were as follows: length, 4.8 cm (range, 3.8-6.9 cm); width, 3.8 cm (range, 2.8-5.2 cm); and mean diameter, 4.3 cm (range, 3.3-5.8 cm). Tumors usually appeared as polypoid or fungating intraluminal masses (n = 7). Perirectal infiltration commonly extended to the pelvic side wall or the presacral space (n = 5). All eight patients had lymphadenopathy, frequently larger than 3 cm in diameter (n = 3), which most commonly involved the perirectal lymph node station (n = 7). There was no evidence of bowel obstruction in any of the patients. Distant metastasis involving the liver was noted in one patient. CONCLUSION: On CT scans, primary rectal malignant melanomas appeared as bulky intraluminal fungating masses in the distal rectum, focally expanding and obscuring the lumen without causing obstruction, with perirectal infiltration and frequently enlarged lymph nodes.     

原发性肛管直肠恶性黑色素瘤的CT和MRI表现

目的：探讨原发性肛管一直肠恶性黑色素瘤（AMM）的CT和MRI表现。方法：回顾性分析本院经病理证实的15例AMM患者的临床、CT、MRI和病理资料。11例行CT检查,3例行MRI检查,1例行CT和MRI检查。结果：15例AMM中,10例病变位于直肠远端与肛管交界处,2例位于直肠,3例位于肛管。肿瘤形态呈蕈伞形肿块9例,肠壁环形增厚4例,肠壁未见明显增厚2例。4例有肺部或者肝脏转移,5例有周围淋巴结转移。15例患者均未见明星的肠梗阻征象。CT平扫示肿块呈稍低密度,最大径约2～4cm,增强后强化方式不一,以中度强化为主。MRI示肿瘤在T2wI上以等信号为主,T2wI上以稍高信号为主,DWI上呈高信号,增强后均有明显强化。结论：AMM的CT和MRI表现具有一定特征性;但AMM病灶较大时,MRI信号不具有黑色素瘤特异性的典型信号。CT检查有助于发现远处转移灶,MRI检查对其鉴别诊断有提示价值。     

外伤性气颅CT征象分析

外伤性气颅在颅脑损伤中并不少见,CT检查能明确外伤性气颅的部位、范围,为临床治疗提供可靠的依据。总结分析我院2000年至2004年33例外伤性气颅CT征象现报道如下:1材料与方法1.1一般资料33例外伤性气颅中男性31例,女性2例,年龄4岁～65岁,平均年龄28岁。临床上均有明确的头部外伤病史,其中,车祸伤19例,高处坠落伤5例,打架斗殴致伤9例。33例患者分别表现为眶周瘀血(熊猫眼)、球结膜下瘀血或乳突区皮肤瘀血。其中,10例患者伴有鼻腔出血,4例患者伴有外耳道出血,3例患者合并脑脊液鼻漏,1例患者合并脑脊液耳漏。1.2检查方法全部病例均采用眶耳线…     

结节性硬化的CT征象分析

目的分析结节性硬化的CT征象以提高对本病的认识。方法14例临床证实的结节性硬化患者均经脑部与腹部CT平扫,其中,6例患者又经对比增强CT扫描。对所有患者的CT表现与临床资料进行了回顾性分析。结果在14例结节性硬化患者中,室管膜下结节见于14例,室管膜下巨细胞星形细胞瘤4例,皮质和皮质下结节6例,脑白质病变2例,肾脏血管平滑肌脂肪瘤4例,肝脏肿块1例。结论脑部与肾脏结节性硬化具有利于确诊本病的特征性CT征象。