超声引导下细针穿刺评估甲状腺结节应变率比值的诊断价值

目的探讨超声引导下细针穿刺(US-FNA)评估弹性应变率比值(SR)最佳诊断界值点诊断甲状腺良、恶性结节的应用价值。方法回顾性分析在我院检查的164例患者167个结节弹性应变率比值(SR),以手术病理为金标准,采用受试者工作特征(ROC)曲线计算出良、恶性结节弹性应变率比值的最佳临界值。所有结节均采取US-FNA检查,排除细胞学无相关诊断(不满意)结果的病例,将入组的163个结节的细针穿刺抽吸细胞学结果与病理结果或随访结果进行对照研究。结果通过ROC曲线得出SR最佳诊断临界值为0.50,曲线下面积0.890。US-FNA诊断SR0.50甲状腺结节的灵敏度、特异度、阳性预测值、阴性预测值及准确率分别为97.18%,80.00%,97.18%,80.00%,95.06%。结论US-FNA细胞学检查对SR0.50的甲状腺结节有较高的诊断价值。弹性应变率(SR)可用于评估甲状腺结节的良、恶性,联合细针穿刺能有效提高恶性结节检出率,并可作为穿刺前评估指标。     

超声弹性应变率比值在颈部淋巴结良恶性鉴别诊断中的应用价值探讨

目的：探讨超声弹性应变率比值在颈部淋巴结良恶性鉴别诊断中的应用价值。方法分析70例70个经穿刺病理证实的恶性淋巴结超声弹性图像以及66例66个健康志愿者的颈部淋巴结超声弹性图像,计算所观察淋巴结与同等深度周边正常软组织的弹性应变率比值（strain rate）。构建受试者应用曲线,建立最佳截断值。结果136个颈部淋巴结中,恶性70个,良性66个。恶性结节应变率比值均值为2．53±0．82,良性淋巴结应变率比值的均值为1．08±0．49。两者差别有统计学意义（ P ＜0．05）。构建 ROC曲线分析得出,以1．950为诊断的最佳临界点,对应的曲线下面积为0.918,以1．950为弹性成像应变率比值临界点判断颈部淋巴结良恶性的敏感性、特异性和准确性分别为77．0％、97.0％、86．8％。结论超声弹性应变率比值在颈部淋巴结良恶性的鉴别诊断中有较高的诊断应用价值。     

超声弹性应变率比值(SR)对甲状腺TI-RADS 4类结节的诊断价值

目的探究弹性应变率比值(SR)在鉴别诊断甲状腺影像报告和数据系统(TI-RADS)4类结节中的应用价值。方法回顾性分析152例患者的154个甲状腺结节声像图特征,依据甲状腺影像报告和数据系统(TI-RADS)对相应的结节进行分类,其中TI-RADS 4a、4b和4c类分别为17个、31个和106个;所有结节均行弹性成像检查,并记录弹性应变率比值(SR),绘制受试者操作特征(ROC)曲线,获得弹性应变率比值(SR)鉴别诊断甲状腺良恶性结节的最佳界值。将入组的154个结节的SR值与病理结果进行对照研究。结果弹性应变率比值SR0.50的甲状腺结节考虑为恶性,SR诊断恶性76个,良性78个;经术后病理证实,恶性78个,良性76个,SR诊断结果与实际结果差异相比较有统计学意义(P0.05)。SR诊断TI-RADS 4类结节的准确性为88.31%,灵敏度为87.18%、特异度为89.47%、阳性预测值为89.47%、阴性预测值为87.18%。结论 SR能显著提高甲状腺结节诊断的准确性,对TI-RADS 4类结节有特殊的应用价值。     

弹性应变率比值联合BI-RADS对乳腺小肿块良恶性的鉴别诊断价值

目的 :探讨弹性应变率比值(SR)联合BI-RADS对乳腺小肿块的诊断价值,旨在提高该病的诊断水平。方法 :回顾性分析200例(390个小肿块,直径≤15 mm)乳腺肿块患者的超声BI-RADS分类和SR,并与手术病理结果进行比较。通过构建ROC,分析SR联合BI-RADS对乳腺小肿块良恶性的鉴别诊断能力。结果:390个小肿块中,良性237个,恶性153个;良性肿块的SR显著低于恶性肿块(P0.05);SR联合BI-RADS诊断乳腺微小病灶的灵敏度、阴性预测值及ROC曲线下面积均显著高于单用SR、BI-RADS分类(均P0.05)。结论 :SR联合BI-RADS可提高对直径≤15 mm乳腺小肿块恶性风险的评估能力及诊断准确性。     

超声弹性应变率比值法与弹性分级法在甲状腺占位性病变诊断中的比较研究

目的：比较超声弹性成像应变率比值法及弹性成像分级法对良、恶性甲状腺占位性病灶的鉴别诊断价值。方法：对手术病理证实的129个甲状腺占位性病变的超声弹性图像进行回顾性分析,对弹性分级法及弹性应变率比值法分别用受试者工作特征曲线（ROC曲线）评价其诊断价值,并比较两种方法的敏感性、特异性及准确性。结果：超声弹性应变率比值法及弹性评分法判断甲状腺占位性病灶的ROC曲线下面积（Az）分别为：0.972和0.938,差异无统计学意义（Z=0.904,P〉0.05）;二者判断甲状腺良、恶性病灶的敏感性、特异性、准确性分别为81.0%、91.7%、89.9%和81.0%、88.0%、86.8%,二者比较敏感性、特异性、准确性差异均无统计学意义（P〉0.05）。结论：超声弹性应变率比值法作为一种半定量的评价方法相对更加客观,并且同弹性分级法一样,是一种有效的鉴别诊断甲状腺良、恶性病灶的影像学检查方法。     

应变率比值法与面积比值法联合应用在乳腺结节鉴别诊断中的价值

目的探讨超声弹性成像(ultrasound elastography,UE)技术应变率比值(strain ratio,SR)与面积比值联合应用在乳腺结节(BI-RADS 4类、直径≤2cm)鉴别诊断中的价值,为临床诊断及治疗提供重要依据。方法对60例女性患者检出的69个乳腺结节,常规超声检查后启用超声弹性成像模式,获得结节的应变率比值及面积比值,并根据应变率比值3.08为良性,≥3.08为恶性,面积比值1.1为良性,≥1.1为恶性,判定结节的良恶性,并与病理结果进行对照。结果超声弹性成像应变率比值的准确性为92.8%,超声弹性成像面积比值的准确性为88.4%,超声弹性成像应变率比值联合面积比值诊断的准确性为94.2%。结论超声弹性成像应变率比值与面积比值联合应用可以提高乳腺结节鉴别诊断的准确性。     

SE及SWE技术对≤1 cm的TI-RADS 4类甲状腺结节的鉴别诊断价值

目的：探索应变弹性成像(strain elastography,SE)与剪切波弹性成像(shear-wave elastography,SWE)对最大径≤1 cm的甲状腺影像报告和数据系统(Thyroid Imaging Reporting and Data System,TI-RADS)4类甲状腺结节的鉴别诊断价值。方法：回顾并分析251例患者的263个甲状腺结节的超声检查结果,患者术前均行常规超声、SE及SWE检查,以手术后病理学检查或细针穿刺活检结果为金标准。在SE图像上,以结节周围同深度的甲状腺组织为参照,测量弹性应变率比值(strain ratio,SR);在SWE图像上同理测量剪切波速度比(E_ratio)。通过受试者工作特征(receiver operating characteristic,ROC)曲线得到SR及E_ratio诊断截断值,评估不同检查方法的诊断效能。结果：研究共纳入恶性病灶144个,良性病灶119个。恶性组的SR和E_ratio值分别高于良性组(SR:3.14 vs 1.20;E_rat...     

超声弹性成像应变率比值法在乳腺良恶性结节鉴别诊断中的应用

目的:探讨超声弹性应变率比值法在乳腺良恶性结节鉴别诊断中的应用。方法:74例共82个病灶均行常规超声检查,测量病灶的应变率比值,并以病理结果作为对照。结果:82个病灶中,良性57个,恶性25个,良、恶性乳腺肿块弹性应变率比值分别为1.71±0.53和3.93±0.85,二者差异有统计学意义(P0.001)。应变率比值法对乳腺良恶性结节的敏感度、特异度、准确度分别为93.1%、94.9%、89.1%。结论:超声弹性应变率比值法有助于乳腺良恶性结节的鉴别,具有一定的临床应用价值。     

超声弹性应变率比值在TI-RADS(4-6)类合并钙化的甲状腺结节中的价值

目的探讨超声弹性应变率比值在鉴别诊断甲状腺TI-RADS(4-6)类合并钙化结节中的应用价值。方法常规超声观察303例患者(共324个结节)甲状腺结节的边界、内部回声、是否合并钙化、纵横比、内部及周边血流情况等,依据甲状腺影像数据评分与报告系统(TI-RADS)对相应的甲状腺结节进行分类,同时进行超声弹性成像记录弹性应变率比值,绘制ROC曲线,获得弹性应变率比值鉴别诊断甲状腺良恶性结节的最佳界值。其中TI-RADS 4-6类患者137例(137个结节)分钙化组(Ⅰ组)和无钙化组(Ⅱ组),钙化组又以钙化大小分为微钙化组(≤2mm)和粗钙化组。以病理结果为金标准,绘制ROC曲线,评价弹性应变率比值在Ⅰ、Ⅱ组病变中的应用价值。结果弹性应变率界值为0.55。微钙化组和Ⅱ组的敏感性、特异性、准确性、阳性预测值分别为88.9%、71.4%、86.5%、95.2%和82.4%、78.9%、81.1%、87.5%,ROC曲线下面积(AUC)分别为0.808、0.831;粗钙化组ROC曲线AUC为0.655。结论应用TI-RADS分类标准联合弹性应变率比值可提高鉴别诊断Ⅱ组和微钙化组甲状腺结节良恶性的敏感性、特异性和准确性,指导临床对甲状腺合并钙化结节采取正确的处理,达到早期诊断,早期治疗的效果。     

声脉冲辐射力弹性成像对甲状腺结节良恶性鉴别诊断价值

目的 分析声脉冲辐射力（ARFI）弹性成像对甲状腺结节良恶性鉴别诊断价值。方法 选取2020年6月至2022年11月医院收治的甲状腺结节患者72例（85个结节）为研究对象,均接受常规超声及ARFI弹性成像检查,以组织病理结果为“金标准”,分析ARFI弹性成像鉴别诊断甲状腺结节良性恶。结果 本研究中85结节,经病理明确诊断良性病灶57个,恶性病灶28个;常规超声诊断在85个结节中共检出61个良性病灶,24个恶性病灶,诊断灵敏度60.7%(17/28)、特异度87.8%(50/57)、准确度为78.7%(67/85);恶性组声触诊组织成像（VTI）面积比、剪切波速度（SWV）、SWV比值均高于良性组,差异有统计学意义（P<0.05）;ARFI弹性成像参数绘制受试者工作特征（ROC）曲线结果显示,VTI面积比、SWV、SWV比值及联合诊断甲状腺结节良恶性的曲线下面积（AUC）均>0.7,具有一定诊断价值,且联合诊断价值最高。结论 ARFI弹性成像诊断甲状腺良恶性灵敏度、特异度较高,具有较高诊断价值。     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

Controversies in cervical spine imaging in trauma patients

No area of emergency radiology has generated as much discussion in recent years as the subject of cervical spine imaging for trauma patients. This review will be in three parts. The first will examine the indications for cervical imaging and will focus on those factors that make patients at high risk or low risk for cervical injury. The second part will discuss the merits of radiography and computed tomography as the main screening diagnostic examination. In addition to the roles of each modality in the evaluation process, such factors as efficacy of diagnosis, time (duration) of study, and cost will be discussed. Finally, the third part will explore the methods currently employed to clear the cervical spine in comatose patients.Presented at the Annual Meeting of the American Society of Emergency Radiology, Las Vegas, Nevada, 22–25 October, 2003     

Uterine contractions: Possible diagnostic pitfall at MR imaging

A total of 206 nongravid patients with various gynecologic problems underwent pelvic magnetic resonance (MR) examinations that included both sagittal T2-weighted and contrast agent–enhanced T1-weighted images. MR images were retrospectively reviewed to identify changes in endometrial configuration on serial images obtained during the same MR examination. In 20 MR examinations (all in women of reproductive age), endometrial distortion due to myometrial bulging was noted on T2-weighted or contrast-enhanced T1-weighted images. It was absent on other MR images obtained at different times. Myometrial bulging exhibited low signal intensity in 18 examinations. The finding resembled adenomyosis or leiomyoma on T2-weighted or contrast-enhanced T1-weighted images. These results evidence the presence of transient myometrial bulging and transient low-intensity myometrium in the nongravid uterus. This phenomenon is thought to represent uterine contraction. Clinicians should be aware of the potential presence of transient low-signal-intensity myometrial bulging that could present diagnostic problems in the normal uterus.     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

Right-side aortic arch with aneurysm of aberrant left subclavian artery: MR imaging appearance.

Reports of aneurysms of the subclavian artery in both normal and anomalous aortic arches have been rare. The authors describe a patient with a right-side aortic arch and an aneurysm of the aberrant left subclavian artery, which, to the authors' knowledge, is a previously unreported association. At presentation, the aneurysm appeared as a calcified left superior mediastinal mass. Magnetic resonance imaging enabled preoperative diagnosis and guided surgical planning.     

Adrenal tissue characterization with 0.5-T MR imaging: Value of T2*-weighted images

The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor–liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.