子宫肌瘤的低场MRI诊断

目的 :探讨低场MRI对子宫肌瘤的诊断价值。方法 :对 16例子宫肌瘤患者行MRT1 WI和T2 WI多方位扫描。结果 :14例B超和DSA表现支持MRI诊断 ,2例为子宫阔韧带肌瘤而手术证实。肌瘤在低场MRT1 WI上表现等信号和T2 WI上表现为特征性低信号。结论 :低场MRI对子宫肌瘤在观察大小、形态、位置与子宫腔的关系和肌瘤在定性方面上有较高的诊断价值     

Transient uterine contraction mimicking adenomyosis on MRI

Transient myometrial contraction as a physiological phenomenon may simulate pathological conditions, such as a focal or diffuse adenomyosis. Clinicians should be aware of the potential presence of this phenomenon and imaging should be repeated after a suitable interval when the nature of a bulge or a region of low intensity in the myometrium is in doubt. In this paper, we report a transient myometrial contraction that mimics an adenomyosis, but disappears in repeated series. Received 10 February 1997; Revision received 9 April 1997; Accepted 21 May 1997     

MRI of adenomyosis: changes with uterine artery embolization

OBJECTIVE: Our objective was to describe the MRI features of patients with pure or dominant adenomyosis treated with uterine artery embolization (UAE) and to correlate imaging features with symptoms. SUBJECTS AND METHODS: Nineteen patients with symptomatic pure or dominant adenomyosis on MRI were referred for UAE. All 19 patients had repeat MRI 4 months after UAE. The MR images obtained before and after UAE were evaluated for maximal junctional zone thickness, junctional zone-myometrial ratio, uterine volume, and the presence of avascular regions. Patients were asked to complete a questionnaire about their symptoms before and 3 and 12 months after UAE. RESULTS: Uterine volume decreased significantly after UAE (p < 0.01). The mean uterine volume reduction was 25.1%. Junctional zone thickness decreased significantly (p < 0.001). The junctional zone-myometrial ratio did not decrease significantly (p = 0.526). Fourteen (73.7%) of the 19 patients showed devascularized change within the adenomyotic region. Eighteen patients completed a questionnaire at 3 months. Sixteen (88.9%) of the 18 reported an improvement in symptoms, whereas the two remaining patients (11.1%) reported no change (p < 0.001). Of the 16 patients with clinical improvement, 11 had devascularized areas after UAE and five did not. Eleven of the 18 patients who completed a questionnaire 3 months after UAE also completed a questionnaire 12 months after UAE. Ten of these 11 patients still reported continued improvement, and one patient reported a worsening of symptoms. CONCLUSION: UAE in patients with pure or dominant adenomyosis results in decreased uterine volume and regions of devascularization. Most patients reported an improvement in clinical symptoms within 3 months after UAE. Some patients reported benefit for at least 1 year; however, the long-term durability of symptomatic relief remains unknown.     

CT and MRI of retroperitoneal edema associated with large uterine leiomyomas

Two cases of retroperitoneal edema surrounding the left ovarian vein that were associated with large uterine leiomyoma are presented. This finding was not associated with any specific lateralizing symptoms or with any evidence of malignancy. One patient underwent hysterectomy with surgical exploration of the retroperitoneum that confirmed the absence of malignancy. The CT and MR findings in this entity are described and possible etiological mechanisms discussed. Recognition that large leiomyoma can be associated with benign retroperitoneal edema may help avoid inappropriate management.     

低场MRI对诊断子宫肌瘤与子宫腺肌病的应用价值

目的分析子宫肌瘤与子宫腺肌病的MRI表现特点,探讨MRI对两病的诊断价值。方法回顾性分析25例经手术病理证实的子宫肌瘤和子宫腺肌病患者MRI资料。结果16例子宫肌瘤患者中,共检出病灶24个。T1WI表现均为等低信号,不易识别;T2WI表现为低、高或混杂信号;病灶多有包膜、边界清晰,周围可见低或高信号环;增强扫描可见病灶不同程度强化。7例子宫腺肌病中,弥漫性5例、局限性2例。T1WI及T2WI信号不均,T2WI表现结合带弥漫性或不规则增厚,结合带改变具有诊断特异性;病灶无包膜与周围组织界线不清;增强扫描无明显强化,为等或低信号：2例为子宫肌瘤合并子宫腺肌病。T2WI及增强扫描有助于两病的显示及鉴别诊断。1例子宫肌瘤误诊为子宫腺肌病,1例子宫腺肌病误诊为子宫肌瘤,MRI对两病诊断的敏感性100％,准确率92％。结论选择合适的MRI检查序列与方法对两病鉴别诊断只有重要的价值。     

Triple-phase dynamic MRI of intratumoral vessel density and hyalinization grade in uterine leiomyomas

OBJECTIVE: Our purpose was to clarify the relationship between the tissue vascularity shown on triple-phase dynamic MRI and the number of intratumoral vessels and degree of hyalinization, which are two histopathologic changes in leiomyoma. SUBJECTS AND METHODS. The subjects were 10 premenopausal patients with 20 leiomyomas who had undergone surgery without preoperative gonadotropin-releasing hormone analogue treatment. Intratumoral vessel density was determined by the mean number of intratumoral vessels with at least one smooth-muscle layer in the optic fields magnified 100 times. Hyalinization grade was determined by the severity of hyalinization, histopathologically classified in three grades. The enhancement index (EI) of the leiomyoma was calculated using the formula EI(t) = [S(t) - S(0)] / S(0), where S(0) is the signal intensity on pre-enhanced T1-weighted images and S(t) is the signal intensity on each dynamic phase image (t = 20, 60, and 180 sec) [corrected]. The histopathologic parameters of intratumoral vessel density and hyalinization grade were compared with the enhancement indexes obtained from the triple-phase dynamic MRI. RESULTS: We found positive correlations between intratumoral vessel density and EI(60) and between intratumoral vessel density and EI(180) (in both cases, p = 0.0028 and r = 0.69). We found significant differences among the mean enhancement indexes for each hyalinization grade at all dynamic phases (p < 0.01). The leiomyomas with lower intratumoral vessel densities tended to show greater hyalinization. CONCLUSION: Our results showed that leiomyomas with only slight hyalinization or with abundant vessels were well enhanced, but the leiomyomas with severe hyalinization enhanced poorly.     

Diffusion-weighted imaging for prediction of volumetric response of leiomyomas following uterine artery embolization: a preliminary study

Purpose

To determine if pretreatment apparent diffusion coefficient (ADC) of leiomyomas could predict volumetric response (VR) following uterine artery embolization (UAE).

Materials and Methods

We retrospectively studied 11 women who underwent pelvic MRI before and >120 days following UAE. MRI included conventional and diffusion weighted imaging sequences. Percentage change in leiomyoma volume was determined by multiplanar T2‐weighted imaging. A Pearson correlation coefficient was calculated between leiomyoma VR following UAE and the following pre‐embolization parameters: initial volume, relative enhancement, relative T2 signal intensity (SI) and ADC. Receiver operating characteristic (ROC) curve analysis was used to determine the sensitivity and specificity of ADC for predicting volumetric response.

Results

Twenty‐eight leiomyomas were included with a mean interval from UAE to follow‐up MRI of 207 days. The preprocedural volume of the leiomyomas ranged from 18 to 182 cm³ (median 47 cm³). and ADC ranged from 0.37 to 1.71 mm²/s (mean 0.80 mm²/s). All leiomyomas were 100% necrotic following UAE. Leiomyoma VR following UAE was 48% ± 3.5%. with significant correlation between VR and ADC (r = 0.41; P = 0.017) but no correlation with initial leiomyoma volume, relative T2 SI, or relative enhancement. Using a threshold of 0.875 × 10^?3 mm²/s, ADC could predict > 50% VR with sensitivity and specificity of 70% and 83%, respectively.

Conclusion

Pre‐UAE ADC of leiomyomas correlated significantly with percent VR following UAE. In contrast, no correlation was seen between VR post‐UAE and conventional imaging findings. This suggests that VR following UAE depends on leiomyoma histology reflected in DWI rather than features revealed by conventional MRI. J. Magn. Reson. Imaging 2011;33:641–646. © 2011 Wiley‐Liss, Inc.

     

巨大子宫肌瘤的 MSCT 与 MRI 诊断

子宫肌瘤是女性生殖系统常见病、多发病。巨大子宫肌瘤体积大、占据范围广,易与邻近脏器相贴或相互推移,超声诊断作用受限,而 MSCT、MRI 可以多平面显示,且具有较高的空间分辨率及软组织分辨率,显示出较大的优势。本研究回顾性分析经手术病理证实的32例巨大子宫肌瘤(最大径>7 cm)的MSCT 及 MRI 表现,旨在提高巨大子宫肌瘤的诊断水平。     

Differentiation between completely hyalinized uterine leiomyomas and ordinary leiomyomas: three-phase dynamic magnetic resonance imaging (MRI) vs. diffusion-weighted MRI with very small b-factors

PURPOSE: To assess the possibility of differentiating between completely hyalinized leiomyomas and ordinary leiomyomas by using diffusion-weighted (DW) magnetic resonance imaging (MRI) (DWI) employing very small b-factors (b = 1.51 and 55.3 seconds/mm(2)) in comparison with three-phase dynamic MRI. MATERIALS AND METHODS: The subjects were 25 patients with 52 histopathologically confirmed uterine leiomyomas. All leiomyomas were divided into two histopathologic subtypes (5 completely hyalinized leiomyomas and 47 ordinary leiomyomas). For each leiomyoma, the enhancement index (EI) at three-phase dynamic MRI and apparent diffusion coefficient (ADC) were obtained and then compared. RESULTS: The EIs at second and third dynamic phases clearly differentiated the two types of leiomyomas without overlap of values. ADCs also clearly differentiated the two types of leiomyomas without overlap of values. Moreover, there were significant positive correlations between ADCs and EIs at all dynamic phases (r = 0.41-0.50, P < 0.01). CONCLUSION: Not only three-phase dynamic MRI but also DWI with very small b-factors could be useful for differentiating completely hyalinized leiomyomas from ordinary leiomyomas.     

子宫动脉栓塞对子宫腺肌病患者卵巢功能的影响

目的评价子宫动脉平阳霉素碘油乳剂栓塞对子宫腺肌病患者卵巢功能的影响。方法对33例子宫腺肌病患者用平阳霉素碘油乳剂进行子宫动脉栓塞,并检测栓塞前和栓塞后第1、3、6和12个月的患者以及45例正常体检女性(对照组)同期血中的雌二醇(E2)、卵泡刺激素(FSH)、黄体生成素(LH)和催乳素(PRL)水平,其后对两组结果作比较研究。结果栓塞前33例患者的FSH、LH、E2水平与正常对照组差异无显著性(P>0.05),而PRL水平高于正常对照组(P<0.05);栓塞术后1、3、6和12个月的患者FSH、LH、E2皆与术前无显著性差异(P>0.05),但PRL水平较栓塞前明显下降(P<0.05)。结论子宫动脉平阳霉素碘乳剂栓塞治疗子宫腺肌病并不影响患者的卵巢功能,且有利于降低患者的PRL水平。     

MRI characteristics of the uterine junctional zone: from normal to the diagnosis of adenomyosis

OBJECTIVE: MRI was the first imaging technique to permit the visualization of the uterine junctional zone and remains the imaging method of choice to evaluate it and its associated pathology. CONCLUSION: Adenomyosis can be diagnosed using MRI with a diagnostic accuracy of 85%. The most important MR finding in making the diagnosis is thickness of the junctional zone exceeding 12 mm. The principal limitation of MRI is the absence of a definable junctional zone on imaging, which occurs in 20% of premenopausal women.     

MR imaging of uterine leiomyomas and their complications

Magnetic resonance (MR) imaging in eight patients with uterine leiomyomas and in eight normal female volunteers clearly depicted the size, shape, and position of the corpus uteri and demonstrated adjacent anatomic structures to good advantage in transaxial, coronal, and sagittal planes. Spin echo (SE) with short repetition time (TR) and short echo time (TE) values was judged best for overall delineation of anatomic structures. Longer TR and TE times were used to differentiate myometrium from endometrium. Detection and characterization of complications of uterine myomas were facilitated by the use of multislice/multiecho SE techniques, but in general TE values greater than 60 ms were not needed to differentiate endometrium from myometrium and in most cases did not improve the MR depiction of abnormalities. Calculated T1 and T2 relaxation times from this preliminary study do not demonstrate a clear advantage in further characterizing uterine abnormalities.     

肝脏肿瘤微波消融后MRI信号演变解读

目的 对肝脏恶性肿瘤微波消融(MWA)术后MRI信号随时间的演变进行解读.方法 56例患者共56个肝肿瘤病灶,在MWA术后第2天、1个月、6个月行上腹部MRI平扫及增强扫描.观察不同时间点消融区T1WI、T2WI、DWI及增强扫描的信号变化,并判断是否存在肿瘤复发.结果 MWA后2d,消融区在T1WI、T2WI序列表现为靶样结构,T1WI表现为中央高信号的消融坏死区与周围环绕的低信号带,T2WI表现为低信号的消融坏死区及周围环绕的高信号带;术后1个月及6个月消融区体积萎缩,T1WI及T2WI仍可见靶样结构,T1WI显示消融坏死区信号升高.增强扫描显示MWA后2d,消融区周围存在异常高灌注,术后2d、1个月及6个月消融坏死区均无强化.DWI序列显示消融后2d,消融区周围反应性信号增高,术后1个月及6个月信号逐渐降低.结论 肝脏肿瘤MWA术后消融区信号变化是随时间演变的过程,对消融区MRI信号的正确解读有助于疗效判断及方案制定.     

MR imaging-guided focused ultrasound surgery of uterine leiomyomas: a feasibility study

The feasibility and safety of magnetic resonance (MR) imaging-guided focused ultrasound surgery for uterine leiomyomas is reported. Sequential sonications were delivered to nine targets. Temperature-sensitive phase-difference MR imaging monitored the location of the focus and measured tissue temperature elevations, ensuring therapeutic dose. MR images and hysterectomy specimens were evaluated. Six leiomyomas received full therapeutic doses, and 98.5% of the sonications were visualized. MR thermometry was successful in all sonications and cases. Focal necrotic lesions were seen in all cases at MR, and five were pathologically confirmed. MR imaging-guided focused ultrasound causes thermocoagulation and necrosis in uterine leiomyomas and is feasible and safe, without serious consequences.     

Incidence and characteristics of uterine leiomyomas with FDG uptake

Objective  Uterine leiomyomas sometimes show focal ¹⁸F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) images that may result in a false-positive diagnosis for malignant lesions. This study was conducted to investigate the incidence and characteristics of uterine leiomyomas that showed FDG uptake. Methods  We reviewed FDG-PET and pelvic magnetic resonance (MR) images of 477 pre-menopausal (pre-MP, age 42.1 ± 7.3 years) and 880 post-MP (age 59.9 ± 6.8 years) healthy women who underwent these tests as parts of cancer screening. Of 1357, 323 underwent annual cancer screening four times, 97 did three times, 191 did twice, and the rest were screened once. Focal FDG uptake (maximal standardized uptake value > 3.0) in the pelvis was localized and characterized on co-registered PET/MR images. Results  Uterine leiomyomas were found in 164 pre-MP and 338 post-MP women. FDG uptake was observed in 18 leiomyomas of 17 of the 164 (10.4%) pre-MP women and in 4 leiomyomas of 4 of the 338 (1.2%) post-MP women. The incidence was significantly higher in pre-MP women than in post-MP women (chi-square, P < 0.001). Of the 22, 13 showed signal intensity equal to or higher than that of the myometrium on T2-weighted MR images, which suggested abundant cellularity, whereas the majority of leiomyomas without FDG uptake showed low signal intensity. Of the 13 women, 12 examined more than twice showed substantial changes in the level of FDG uptake in leiomyomas each year with FDG uptake disappearing or newly appearing. These changes were observed frequently in relation with menopause or menstrual phases. Conclusions  Leiomyomas with focal FDG uptake were seen in both pre-and post-MP women with a higher incidence in pre-MP women. Abundant cellularity and hormonal dependency may explain a part of the mechanisms of FDG uptake in leiomyomas. It is important to know that the level of FDG uptake in leiomyomas can change and newly appearing FDG uptake does not necessarily mean malignant transformation.     

子宫肌瘤的MRI诊断

目的探讨MRI对子宫肌瘤的诊断价值及其表现特征.方法对26例疑子宫肌瘤的患者分别行B超和盆腔MRT1WI、T2WI多方位扫描,其中11例同时行动态增强检查,并与术后病理进行对照分析.结果除2例术后病理证实为内膜息肉和卵巢炎性假瘤外,余MRI诊断均与术后病理相符,诊断准确率为92%.B超确诊22例,准确率85%.以手术病理为标准,MRI病灶检出率为89%(55/62),B超检出率为69%(43/62),统计学比较有显著性差异(x2=17.86,P＜0.05).子宫均有不同程度增大或轮廓改变,宫腔变形.肌瘤在T1WI上表现为等或低信号,T2WI上表现为低或混杂信号,动态增强后强化不均匀.结论MRI在显示肌瘤的大小、位置及与宫腔的关系上有较高的诊断价值,可作为B超检查的重要补充手段.     

T2WI 3.0T盆腔风车采集技术在子宫腺肌症及子宫肌瘤中的应用价值

目的探讨3.0 T风车采集(MVXD)技术T2WI在子宫腺肌症及子宫肌瘤中的应用价值。方法前瞻性收集2018年3月至5月北京协和医院超声证实有子宫肌瘤或临床疑诊为子宫腺肌症的患者,均在围排卵期行盆腔3.0 T MRI检查,采集常规轴面快速自旋回波(TSE)T2WI、轴面MVXD T2WI、矢状面TSE T2WI、矢状面MVXD T2WI图像。2名医师分别对4个序列图像进行子宫轮廓清晰程度、运动伪影、对病变的识别能力、诊断确信程度及整体图像质量评分。采用Cohen Kappa法评价2名医师间评分的一致性,采用Wilcoxon配对符号秩和检验比较采用常规TSE及轴面MVXD序列采集T2WI图像质量的差异。结果20例患者纳入研究,均采集了常规轴面TSE T2WI及轴面MVXD T2WI;19例采集了常规矢状面TSE T2WI及矢状面MVXD T2WI。9例仅存在明显子宫腺肌症病灶,6例仅存在明显子宫肌瘤,5例同时合并子宫腺肌症及子宫肌瘤。和传统的常规TSE序列相比,2名医师采用MVXD序列采集的矢状面T2WI和轴面T2WI中,均对子宫轮廓清晰程度、运动伪影、整体图像质量方面的评分更高,差异有统计学意义(P<0.05)。2名医师对图像评价的Kappa值为0.615~0.971,一致性均为好或非常好。结论将T2WI MVXD技术应用于子宫肌瘤或子宫腺肌症患者,相较于常规T2WI技术有利于改善图像质量,且不牺牲对病变的识别、诊断能力。     

2450 MHz与915 MHz微波消融离体牛肝：消融范围、能量输出与转化的差异

目的探讨2450 MHz水冷循环与915 MHz无水冷循环微波消融离体牛肝在毁损范围、能量输出以及能量转化方面的差异。 方法新鲜离体牛肝10副,重量为5.2～6.5 kg。实验分为A组和B组,A组为2450 MHz水冷循环微波消融组,B组为915 MHz无水冷循环微波消融组。每组分别对离体牛肝进行10、20、30、40 min的消融实验。统计两种消融系统在毁损范围（平均径、体积、类圆率）、能量输出以及能量转化方面的数据,并比较其差异。 结果A组和B组的消融平均径随着消融时间延长逐渐增大。B组的消融平均径显著大于A组（P均<0.001）。消融体积在10和20 min时两组间无明显差异（P=0.44、0.65）,消融30 min以后,B组消融体积显著大于A组（P<0.001）。B组消融灶的平均径最大可达6.5 cm,消融体积最大为112.20 cm³（消融40 min）。A组的消融灶类圆率较B组更接近于1（P均<0.001）,A组消融灶的类圆性更好。在能量输出方面,A组显著高于B组（P均<0.001）,相同消融时间A组能量输出为B组的2倍以上。但能量转化效率方面,B组显著高于A组（P均<0.001）。 结论2450 MHz水冷循环微波具有更高的能量输出和类圆性更好的消融范围,但915 MHz无水冷循环微波的能量转化效率更高,所获得的消融范围更大。     

子宫动脉栓塞术治疗子宫肌瘤的中远期疗效

子宫动脉栓塞术治疗子宫肌瘤具有确切的中远期疗效,但其并非一种根治性治疗手段,存在复发和出现新生肌瘤的可能,术后有必要进行长期临床和影像学随访,仍需进行大规模临床研究,分析与其中远期疗效相关的因素,以便指导临床工作。     

子宫肌瘤与子宫腺肌症超声造影强化形式的临床应用

目的：探讨超声造影强化形式在子宫肌瘤与子宫腺肌症鉴别诊断中的临床应用。方法：回顾性分析经手术或病理证实的子宫肌瘤和子宫腺肌症患者70例的超声造影表现,记录造影时病灶的充填方式、与肌层的成像顺序及增强程度等。结果：子宫肌瘤患者50例（72个病灶）,子宫腺肌症患者20例。3 cm以上肌瘤56个,均表现为假包膜先充填,呈周边环状增强,然后肌瘤内部增强,消退时肿瘤中央先消退,包膜增强持续时间较长,与周边正常肌层组织充盈方式显著不同。3 cm以下肌瘤16个,呈环绕型增强8个,树枝型增强2个（混合型增强6个）。20例子宫腺肌症均表现为与子宫肌层同步增强,同步减退,且增强程度低于子宫肌层,呈不均匀增强,可见虫蚀样充盈缺损区。结论：超声造影强化形式对子宫肌瘤和子宫腺肌症的鉴别诊断有重要价值。