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目的探讨继发性附件扭转的CT特征及其诊断效能,构建继发性附件扭转的评分系统。资料与方法收集经手术证实的伴有附件肿物的继发性附件扭转患者37例,以及伴有腹痛、附件肿物的对照组患者34例,分析继发性附件扭转的CT特征,采用受试者工作特征(ROC)曲线评价其诊断效能,构建继发性附件扭转的综合评分系统(AT-CI)。结果与对照组比较,继发性附件扭转以下CT特征发生率较高,包括肿物壁偏心性增厚(X^2=4.41,P<0.05)、附件出血(X^2=12.68,P<0.001)、肿物-子宫之间团块状结构(X^2=13.62,P<0.001)、旋涡征(X^2=10.71,P<0.05)、附件周围脂肪模糊/腹水(X^2=5.82,P<0.05)。其中肿物-子宫之间团块状结构敏感度及诊断价值最高,为81.1%(ROC曲线下面积0.71),旋涡征特异度最高,为91.2%。ATCI诊断效能优于任意单一CT特征(ROC曲线下面积0.83),评分0~2分继发性附件扭转可能性小,3~4分怀疑继发性附件扭转,评分>4分,则高度怀疑继发性附件扭转且特异度为100%。结论继发性附件扭转具有典型的CT特征,包括肿物壁偏心性增厚、附件出血、肿物-子宫之间团块状结构、旋涡征、肿物周围脂肪模糊/腹水。AT-CI是综合了继发性附件扭转全部CT特征的实用评分系统,提高了继发性附件扭转的诊断准确性。  相似文献   
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《中国现代医生》2020,58(9):144-146+封三
目的探讨MSCT在对比剂外渗的急性腹部创伤性动脉损伤诊断中的应用价值。方法回顾性分析本院2016年1月~2018年12月收治的44例急性创伤性腹部动脉损伤患者及58例腹部非创伤性动脉病变患者影像资料,分析急性腹部创伤性和非创伤性动脉病变所致对比剂外渗的相关性。结果 44例创伤性腹部损伤患者通过MSCT及图像后处理技术共检出59支动脉损伤,其中对比剂外渗34支、非对比剂外渗共25支;58例急性腹部非创伤组共检出58支动脉病变,其中8支存在对比剂外渗。对比剂外渗征象创伤组出现率明显高于非创伤性组(χ~2=24.42,P0.05)。结论与非创伤组相比,急性腹部创伤性动脉损伤对比剂外渗征象较为常见,MSCT可以较好地显示创伤性对比剂外渗的直接及间接征象。  相似文献   
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目的对治疗前原发性骶尾部脊索瘤(PSC)CT图像分型,并分析其CT征象,为诊断和个性化治疗提供依据。方法回顾性分析101例PSC患者治疗前的CT图像,包括肿瘤的部位、范围、大小、密度、肿瘤与邻近结构的关系。按照肿瘤的部位由上及下分为Ⅰ~Ⅳ型,并根据肿瘤侵犯的范围从小到大分为a^d亚型。采用Kruskal-Wallis H检验比较PSC各亚型的占比,并对各亚型之间进行两两比较。采用R×C列联表精确概率检验比较分型和亚型肿瘤钙化的发生率。采用单因素方差分析及LSD-t检验对各分型和亚型肿瘤的大小和密度进行分析、比较。结果101例PSC中,Ⅰ~Ⅳ型的发生率分别为17.8%、30.7%、36.6%、14.9%,a^d亚型的占比分别为9.9%、25.7%、58.4%、5.9%。各亚型的占比差异具有统计学意义(P=0.012)。c亚型明显高于a亚型(P=0.039),d亚型明显低于a亚型(P=0.036),其余各型之间无明显差异。各分型肿瘤内钙化的差异无统计学意义(P=0.233);各亚型肿瘤内钙化的差异有统计学意义(P=0.003),a^d亚型肿瘤钙化的比率逐渐增加。Ⅰ型肿瘤的左右径及上下径明显大于Ⅱ~Ⅳ型(P<0.05)。a亚型与b亚型肿瘤之间前后径的差异无统计学意义(P=0.102),b^d亚型之间前后径的差异均有统计学意义(P<0.05);不同亚型肿瘤之间的左右径、上下径之间的差异均有统计学意义(P<0.05),a亚型径线最小,d亚型径线最大。结论101例PSC中,Ⅱ、Ⅲ型最多见,肿瘤较少累及第一骶骨;各亚型中,a型较少见,c亚型最多见,d亚型最少见。肿瘤的密度与分型无关,肿瘤内钙化与亚型有关。Ⅰ型肿瘤侵犯的范围较Ⅱ~Ⅳ型广泛,a^d亚型肿瘤的径线逐渐增大,CT分型有利于判断肿瘤的范围。PSC诊断延迟现象比较明显,但很少发生远处侵犯和转移。CT图像可对治疗前PSC分型,为诊断和个性化治疗提供依据。  相似文献   
5.
Background: Extracellular matrix molecular components, previously linked to multisystem syndromes include collagens, fibrillins and laminins. Recently, we described a novel multisystem syndrome caused by the c.9418G>A p.(V3140M) mutation in the laminin alpha-5 (LAMA5) gene, which affects connective tissues of all organs and apparatus in a three generation family. In the same family, we have also reported a myopic trait, which, however, was linked to the Prolyl 4-hydroxylase subunit alpha-2 (P4HA2) gene. Results of investigation on vitreous changes and their pathogenesis are reported in the present study.Materials and Methods: Nineteen family individuals underwent complete ophthalmic examination including best-corrected visual acuity (BCVA), fundus examination, fundus photography, intraocular pressure measurement, axial length measurement using ocular biometry, Goldmann visual field examination, standard electroretinogram, SD-OCT. Segregation analysis of LAMA5 and P4HA2 mutations was performed in enrolled members.Results: The vitreous alterations fully segregated with LAMA5 mutation in both young and adult family members. Slight reduction of retinal thickness and peripheral retinal degeneration in only two patients were reported.Conclusions: In this work we showed that PVD is a common trait of LAMA5 multisystem syndrome, therefore occurring as an age-unrelated trait. We hypothesize that the p.(V3140M) mutation results in a reduction of retinal inner limiting membrane (ILM) stability, leading to a derangement in the macromolecular structure of the vitreous gel, and PVD. Further investigations will be necessary to elucidate the role of wild type and mutated LAMA5 in the pathogenesis of PVD.  相似文献   
6.
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI.  相似文献   
7.
Zygomatic implant treatment is widely applied for severe maxillary atrophy to help rehabilitate the maxillary dentition. This retrospective study was performed to evaluate the actual radiographic bone–implant contact (rBIC) lengths of zygomatic implants. The records of 28 patients who underwent zygomatic implant surgery and subsequent follow-up examinations between August 2013 and September 2018 in the Department of Oral and Maxillofacial Surgery, Taipei Tzu Chi Hospital were reviewed. The surgeries were performed by a single surgeon using the same treatment protocol. All patients had a computed tomography scan at 1 year after the surgery. Using three-dimensional imaging software, an investigator measured the rBIC lengths of 66 implants and documented their clinical status. The implant survival rate was 100%. The mean rBIC length was significantly longer in male patients than in female patients (20.80 ± 5.88 mm versus 17.79 ± 6.34 mm; P = 0.028). The mean rBIC length of double zygomatic implants was significantly longer when compared to that of single implants (21.11 ± 6.23 mm versus 17.75 ± 5.85 mm; P = 0.027). This article is novel in reporting the exact rBIC lengths of zygomatic implants in a clinical setting. The results showed that zygomatic implants are a viable treatment modality for full-mouth rehabilitation.  相似文献   
8.
《Radiography》2022,28(2):518-523
IntroductionSelection of optimal image acquisition protocols in medical imaging remains a grey area, the superimposed use of the Likert scale in radiological image quality evaluations creates an additional challenge for the statistical analysis of image quality data.Using a simulation study, we have trialled a novel approach to analysing radiological image quality Likert scale data.MethodsA simulation study was undertaken where simulated datasets were generated based on the distribution of Likert scale values according to varying image acquisition protocols from a real dataset. Simulated Likert scale values were pooled in four different ways; the mean, median, mode and the summation of patient Likert scale values of which the total was assigned a categorical Likert scale value. Estimates of bias, MAPE and RMSPE were then calculated for all four pooling approaches to determine which method most accurately represented an expert's opinion.ResultsWhen compared to an expert's opinion, the method of summation and categorisation of Likert scale values was most accurate 49 times out of the 114 (43.0%) tests. The mean 28 times out of 114 (24.6%), the median 23 times out of 114 (20.2%) and the mode 17 times out of 114 (14.9%).ConclusionWe conclude that our method of summation and categorisation of Likert scale values is most often the best representation of the simulated data compared to the expert's opinion.Implications for practiceThere is scope to reproduce this simulation study with multiple observers to reflect clinical reality more accurately with the dynamic nature of multiple observers. This also prompts future investigation into other anatomical areas, to see if the same methods produce similar results.  相似文献   
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目的探讨CT扫描在胸膜外孤立性纤维瘤(E-SFT)中的诊断价值。方法回顾性分析2015年4月至2018年4月于我院接受手术治疗的90例E-SFT患者术前CT检查影像资料和术后病理、免疫组织化学资料,评估CT检查在E-SFT诊断中的应用价值。结果 90例E-SFT患者均为单发肿瘤,免疫组织化学及病理学检查示良性80例,恶性10例;CT检查结果为良性72例,平扫表现为圆形或类圆形软组织密度影,密度不均匀,大部分边缘清晰,增强扫描表现为均匀强化;恶性18例,平扫示肿瘤体积较大,边界不清,密度不均,可见大片不规则低密度区,增强扫描瘤体强化不均匀,低密度区无明显强化;CT诊断的敏感度、准确度、特异性阳性率、阴性率分别为60%(6/10)、82%(74/90)、85%(68/80)、33%(6/18)、94%(68/72)。结论 E-SFT的CT检查影像图像具有一定的特征性,尤其是增强扫描有助于评估纤维瘤的良恶性,可将其作为术前诊断及术后复查评估的有效依据用于临床诊疗工作中。  相似文献   
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