Radiological findings and healing patterns of incomplete stress fractures of the pars interarticularis

Objective The objective was to retrospectively record the CT and MRI features and healing patterns of acute, incomplete stress fractures of the pars interarticularis. Method The CT scans of 156 adolescents referred with suspected pars interarticularis stress fractures were reviewed. Patients with incomplete (grade 2) pars fractures were included in the study. Fractures were assessed on CT according to vertebral level, location of cortical involvement and direction of fracture propagation. MRI was also performed in 72 of the 156 cases. MRI images of incomplete fractures were assessed for the presence of marrow oedema and cortical integrity. Fracture healing patterns were characterised on follow-up CT imaging. Results Twenty-five incomplete fractures were identified in 23 patients on CT. All fractures involved the inferior or infero-medial cortex of the pars and propagated superiorly or superolaterally. Ninety-two percent of incomplete fractures demonstrated either complete or partial healing on follow-up imaging. Two (8%) cases progressed to complete fractures. Thirteen incomplete fractures in 11 patients confirmed on CT also had MRI, and 92% demonstrated oedema in the pars. Ten out of thirteen fractures (77%) showed a break in the infero-medial cortex with intact supero-lateral cortex, which correlated with the CT findings. MRI incorrectly graded one case as a complete (grade 3) fracture, and 2 cases as (grade 1) stress reaction. Six fractures had follow-up MRI, 67% showed partial or complete cortical healing, and the same number showed persistent marrow oedema. Conclusions Incomplete fracture of the pars interarticularis represents a stage of the evolution of a complete stress fracture. The direction of fracture propagation is consistent, and complete healing can be achieved in most cases with appropriate clinical management. CT best demonstrates fracture size and extent, and is the most appropriate modality for follow-up. MRI is limited in its ability to fully depict the cortical integrity of incomplete fractures of the pars, but the presence of marrow oedema on fat-saturated T2-weighted sequences is a useful means of detecting acute spondylolysis.     

Immediate CT findings following embolization of cerebral aneurysms: suggestion of blood–brain barrier or vascular permeability change

Introduction Although endovascular techniques are widely used for the treatment of cerebral aneurysms, the immediate postprocedural brain CT findings have not been reported. Therefore, in the present study we assessed the immediate postprocedural brain CT findings following the uneventful coil embolization of cerebral aneurysms. Methods Included in the study were 59 patients with 61 cerebral aneurysms after uncomplicated coil embolization. Acute subarachnoid hemorrhage was present with 32 of the 61 aneurysms. All patients underwent a brain CT scan just before and within 2 h after the endovascular treatment. If the postprocedural CT scan revealed any new findings, a follow-up CT scan and/or MRI were performed within 24 h. The variables related to the abnormal CT findings were also evaluated. Results Among the 61 immediate brain CT scans, 26 (43%) showed abnormal findings, including cortical contrast enhancement (n=21, 34%), subarachnoid contrast enhancement (n=8, 13%), intraventricular contrast enhancement (n=5, 8%), and striatal contrast enhancement (n=2, 3%). Single or mixed CT findings were also seen. None of the 61 aneurysms was associated with new neurological symptoms after endovascular treatment, and all patients made an uneventful recovery. Abnormal findings were more likely to be found with lower body weight and with increased corrected amounts of contrast material and heparin (P<0.05). Conclusion After uneventful endovascular treatment of cerebral aneurysms, the immediate brain CT findings can reveal various patterns of abnormal contrast enhancement. Recognizing the immediate brain CT findings is important, as they can mimic various diseases.     

Diagnostic limitations of 10 mm thickness single-slice computed tomography for patients with suspected appendicitis

Purpose The aim of this retrospective analysis was to evaluate the accuracy of 10 mm thickness single helical computed tomography (CT) examination for confirming the diagnosis of appendicitis or providing a diagnosis other than appendicitis, including underlying periappendical neoplasms. Materials and methods From April 1, 2001 to March 30, 2005, a total of 272 patients with suspected appendicitis underwent CT examinations. Of the 272 patients, 106 (39%) underwent surgery. Seven CT examinations for seven patients were excluded because of inconsistency of the CT protocol. We therefore reviewed 99 CT images (99 patients) with correlation to surgical-pathological findings to clarify the diagnostic accuracy of CT examinations. We compared the postoperative diagnosis with the preoperative CT report. The final diagnoses were confirmed by macroscopic findings at surgery and pathological evaluations if necessary. Results Of the 99 patients, 87 had acute appendicitis at surgery. The sensitivity, specificity, and accuracy of CT were 98.9%, 75.0%, and 96.0%, respectively. The positive predictive value and negative predictive value were 96.6% and 90.0%, respectively. Among nine patients in the true-negative category, five had colon cancers; and among three patients in the false-positive category, two had cancer of the cecal-appendiceal region as the underlying disease. Conclusion CT examination is useful for patients with suspected appendicitis, but radiologists should be aware of the limitation of thick-sliced single helical CT. They should also be aware of the possibility of other diseases, including coincident abdominal neoplasms and underlying cecal-appendiceal cancer.     

Needle tract implantation after percutaneous interventional procedures in hepatocellular carcinomas: lessons learned from a 10-year experience.

Percutaneous interventional procedures under image guidance, such as biopsy, ethanol injection therapy, and radiofrequency ablation play important roles in the management of hepatocellular carcinomas. Although uncommon, the procedures may result in tumor implantation along the needle tract, which is a major delayed complication. Implanted tumors usually appear as one or a few, round or oval-shaped, enhancing nodules along the needle tract on CT, from the intraperitoneum through the intercostal or abdominal muscles to the subcutaneous or cutaneous tissues. Radiologists should understand the mechanisms and risk factors of needle tract implantation, minimize this complication, and also pay attention to the presence of implanted tumors along the needle tract during follow-up.     

64层CT冠状动脉造影和磁共振多技术扫描联合诊断冠心病

目的：探讨64层螺旋CT冠状动脉造影（CTA）和磁共振心脏多技术扫描联合诊断冠心病（CHD）的临床应用价值。材料和方法：28例拟行冠状动脉造影（CAG）的冠心病患者，于术前1周分别完成64层螺旋CTA及磁共振心脏多技术扫描，以CAG为标准分析CTA与MRI诊断冠心病的各项指标，评价平行试验和系列试验的诊断价值。结果：64层螺旋CTA判断中、重度狭窄血管（≥50％）的敏感度、特异度、准确度、阳性预测值、阴性预测值为87．88％、98．73％、95．54％、96．67％、95．12％。磁共振多技术扫描左室增大8例，室壁明显变薄7例。在476个节段中，29个节段（6．09％）运动减弱或不运动，9个节段（1．89％）出现矛盾运动或室壁瘤。左心功能改变，与正常值相比有统计学意义（P〈0．001）。MRI间接推断中、重度狭窄血管（≥50％）的敏感度、特异度、准确度、阳性预测值、阴性预测值为93．75％、86．54％、89．29％、81．08％、95．74％。两种方法联合平行试验和系列试验总的敏感度、特异度分别为99．24％、85．44％，82．39％、99．83％。结论：64层螺旋CTA和磁共振心脏多技术扫描诊断冠心病各有优势，两者互相补充，联合使用可方便、全面、准确、无创地对冠心病患者进行评估。     

16层螺旋CT功能性胰腺内分泌肿瘤灌注的初步研究

目的探讨功能性胰腺内分泌肿瘤与周围正常胰腺组织的MSCT灌注成像特征.材料和方法12例功能性胰腺内分泌肿瘤患者,男性5例,女性7例,年龄25～69岁,平均43.4岁.采用GE LightSpeed 16层MSCT进行灌注扫描,以3.5m/s的速度团注对比剂50ml,延迟5～7s,对选定胰腺病变层面进行同层动态增强检查扫描.将获得的原始图像传到GE AW4.2工作站,用CT-Perfusion3软件进行分析测量胰腺病变及周围正常胰腺组织的时间密度曲线(TDC)、血流量(BF)、血容量(BV)、平均通过时间(MTT)、表面通透性(PS)及达峰时间(TTP).结果功能性胰腺内分泌肿瘤的BF、BV、MTT及PS分别为(287.73±140.97)ml/(min·100g)、(18.48±5.17)ml/100g、(5.96±3.07)s及(17.37±11.10)ml/(min·100g).周围正常胰腺组织的BF、BV、MTT及PS分别为(162.47±92.44)ml/(min·100g)、(11.77±3.54)ml/100g、(7.13±3.02)s及(17.54±12.88)ml/(min·100g).功能性胰腺内分泌肿瘤组织BF和BV高于周围正常胰腺组织(P=0.02,t=3.257;P=0.000,t=4.71),MTT及PS无统计学意义(P=0.230,t=-1.218;P0.965,t=-0.044).功能性胰腺内分泌肿瘤组织及周围正常胰腺组织TTP分别(27.17±4.98)s及(27.96±4.09)s,两者之间无统计学意义(P=0.591,t=-0.542).结论功能性胰腺内分泌肿瘤组织与周围正常胰腺组织间存在灌注上的差异,对其诊断具有重要的提示意义.     

CT检查中窗技术的合理应用对提高肝内病灶检出率的意义

目的评价在传统软组织窗基础上加用肝组织窗对提高肝内病灶检出率的意义。方法接受腹部CT增强扫描的859例患者的895张顺序编号的CT片是由两位有经验的放射学医师评价的。所有的肝脏成像均采用两种窗技术进行，即起初软组织窗和随后肝组织窗。逐例记录了两种技术检出的病灶数与符合率。确定了利用肝组织窗有新增病灶的患者比例。对两种窗技术在检出病灶数方面的差异进行了统计学分析。结果在859例中，205例（24％）患者在软组织窗和肝组织窗上有肝脏病灶，其中，40例（14．6％）患者随着肝组织窗的加用，检出的病灶数亦增多。这40例中的14例患者具有在软组织窗上看不见的新增病灶。两种窗技术的病灶检出率有统计学差异（P〈0．05）。结论 单一的软组织窗不足以全部发现肝内病灶，因此，有些病灶容易漏诊，而肝组织窗的加用，可有效提高肝脏病灶的检出率与诊断准确性。     

多发骨髓瘤的CT诊断

目的 探讨多发骨髓瘤（multiple myeloma，MM）的X线平片和CT表现特点，提高对MM的认识。方法回顾性分析经骨髓穿刺或临床证实的35例MM的X线平片及CT表现。结果35例MM中，X线平片阴性4例，其中CT亦呈阴性2例。其余病例均有不同程度骨质疏松及骨质破坏。结论MM的X线平片和CT表现具有一定特征，临床、影像、实验室与病理相结合可显著提高本病的诊断准确率。     

肝脏少见肿瘤的CT诊断

目的：探讨CT增强扫描在肝脏少见肿瘤的诊断及治疗方案选择中的价值。方法：回顾性分析8例经手术及病理检查证实、2例经肝脏穿刺活检证实的肝脏少见肿瘤的CT增强表现特征，并对比分析相关的临床表现、实验室检查和手术所见。结果：病理组织学检查证实，本组10例中良性肿瘤3例、恶性肿瘤7例，CT增强扫描显示，5例为囊实性，5例为实质性；8例表现为不均匀强化，2例淋巴瘤无明显强化。CT可较准确地显示肿瘤与肝内血管的毗邻关系以及对肝邻近组织器官的推压与侵犯等，与手术所见一致。临床表现和实验室检查对肝脏少见肿瘤定性诊断价值不大，但有助于与肝细胞癌鉴别。结论：CT增强扫描对肝脏少见肿瘤定性诊断较困难，但结合临床表现与实验室检查仍有助于与肝细胞癌相鉴别；CT增强扫描可准确判断肿瘤的解剖部位及其对邻近组织器官侵犯的情况，从而帮助制定合理、详细的手术方案。     

多排CT小肠成像鉴别小肠结核和克罗恩病的价值

目的 探讨多排CT小肠成像(MDCTE)特征性征象在鉴别诊断肠结核和克罗恩病中的价值.方法 收集安徽医科大学第一附属医院2011年8月至2014年11月经内镜、病理确诊的克罗恩病(CD)22例、结核(ITB)25例患者临床资料.每位患者入院后均行MDCTE检查,记录并分析各种MDCTE征象,寻求鉴别诊断CD和ITB有价值的CT表现.结果 CD和ITB回盲瓣受累分别占54.5%和72.0%,累及降结肠的分别占31.8%和12.0%,累及横结肠分别占18.2%和4.0%;多节段受累患者中,CD组为63.6%,ITB为36.0%;肠系膜侧肠壁增厚在CD中占50.0%,ITB则表现为环形或肠系膜对侧增厚;60.0%的ITB患者和9.1%CD患者有淋巴结中心坏死;36.4%的CD患者出现"梳状征",ITB患者中仅有4.0%,两者差异均有统计学意义(P<0.05).结论 MDCTE征象中,病变节段数、病变累及部位、"梳状征"和淋巴结坏死情况在鉴别诊断CD和ITB中具有参考价值.