子宫腺肌症的MRI表现

目的 探讨子宫腺肌症的磁共振(MRI)征象,为临床诊断提供依据.方法 对43例经手术和病理证实的子宫腺肌症病例的MRI成像检查进行回顾性分析.结果 在43例患者中,弥漫型子宫腺肌症26例,局限型子宫腺肌症17例;其中21例患者合并有子宫肌瘤,17例合并盆腔内巧克力囊肿,15例合并卵巢囊肿.弥漫型子宫腺肌症的MRI成像表现为子宫体积增大,子宫壁结合带弥漫性增厚,结合带与肌层分界不清;在T1WI上表现为等信号,在T2WI上表现为等或略低信号,混杂有散在多发点状高信号灶,宫腔受压变小.增强扫描病灶轻度强化.局限型子宫腺肌症的MRI成像表现为子宫体部或底部局限性增大,相应部位见结合带增厚,与肌层分界不清,呈类圆形或椭圆形,在T1WI上呈等信号,在T2WI上呈略低信号,病灶信号可不均匀,中央部可有多发点状高信号.增强扫描增厚的结合带轻度强化,与强化的子宫肌相比信号略低.MRI同时很好地显示了子宫肌瘤、盆腔内巧克力囊肿和卵巢囊肿等并发症.结论 子宫腺肌症以子宫结合带增厚为特征,MRI能全面显示腺肌症的类型,病变范围和并发症,是评价子宫腺肌症的有效无创伤性影像学手段.     

Value of dynamic enhanced magnetic resonance imaging for distinguishing between ovarian fibroma and subserous uterine leiomyoma

PURPOSE: The purpose of this study was to assess the accuracy of magnetic resonance imaging (MRI), particularly, dynamic MRI, in distinguishing ovarian fibromas from subserous uterine leiomyomas. MATERIAL AND METHODS: Fifteen ovarian fibromas and 15 subserous uterine leiomyomas were retrospectively reviewed. All MR examinations included dynamic contrast-enhanced (DCE) sequences. Morphological criteria (size, T1 and T2 signals, ovarian tissue, associated uterine leiomyoma, and pelvic fluid), arterial vessels, time-intensity curves (maximal enhancement and signal intensity at 30, 60, and 90 seconds), and signal intensity on delayed T1-weighted images were compared between the 2 groups. RESULTS: No significant difference in morphological criteria was noted between the 2 types of masses. Visualization of arterial vessels was more frequent in uterine leiomyomas than in ovarian fibromas (P= 0.002). The DCE MR enhancement rate was higher for uterine leiomyomas than for ovarian fibromas in terms of both maximal enhancement (P < 0.001) and enhancement rate at 30 (P = 0.009), 60 (P = 0.007), and 90 seconds (P = 0.0009). On delayed T1 postcontrast sequence, no statistical difference exists between signal intensity of ovarian fibromas and uterine leiomyomas. CONCLUSION: Our findings suggest that DCE MRI can distinguish ovarian fibromas from uterine leiomyomas and should be used if sonography fails to show the origin of a pelvic mass.     

Case report: Ovarian cavernous haemangioma presenting as a heavily calcified adnexal mass

Haemangioma is an extremely rare tumour of the ovary. We describe the CT and MRI findings of a heavily calcified ovarian haemangioma in a 69-year-old woman presenting with adnexal torsion. CT showed a well-circumscribed mass with extensive punctate calcifications, located posterior to the uterus. MR images showed dark signal intensities of the mass on both T(1) and T(2) weighted images, with poor enhancement of the mass on contrast-enhanced T(1) weighted images. MR images also demonstrated a beak-like protrusion from the adnexal mass, representing the adnexal torsion. This is the first case report of a heavily calcified ovarian haemangioma in the English literature. Although rare, ovarian haemangioma should be included in the differential diagnosis of a heavily calcified adnexal mass.     

动态MRI对卵巢纤维瘤与浆膜下子宫肌瘤的鉴别诊断价值

目的　探讨MR早期动态增强对MR平扫表现为T2 WI等或低信号的卵巢纤维瘤与浆膜下子宫肌瘤鉴别诊断的价值。方法　分析经手术病理证实的 4 5例卵巢纤维瘤及浆膜下子宫肌瘤MR平扫及早期动态增强表现 ,其中卵巢纤维瘤 10例 ,浆膜下子宫肌瘤 35例。结果　卵巢纤维瘤2例T2 WI呈等信号 ,8例呈低信号 ,T1WI皆为低信号 ,增强早期多为弱强化 ,延迟期消退缓慢 ,早期强化率值 (SI10 0 )低 ,曲线达到高峰所需时间 (TTP2 0 0 )长 ;浆膜下子宫肌瘤 7例T2 WI呈等信号 ,2 8例呈低信号 ,T1WI皆为低信号 ,增强扫描早期多为中 高度强化 ,早期强化率值SI10 0 高 ,曲线达到高峰所需时间TTP2 0 0 短 ;两组强化曲线形态不同 ,差异有显著性意义 (P <0 0 0 1)。结论　MR平扫表现相似的卵巢纤维瘤和浆膜下子宫肌瘤 ,早期动态增强扫描强化曲线形态不同 ,有助于两者的鉴别。     

Collagenous fibroma (desmoplastic fibroblastoma): a new case originating in the palate

A 49-year-old woman presented with a painless slowly growing but huge polypoid palatal mass. On magnetic resonance imaging (MRI), areas of low signal intensity were consistent with a fibrous tumour. T(1) and T(2) weighted MRI after Gd-DTPA administration highlighted a well-circumscribed, purely soft tissue process. Histological analysis of the operative specimen detected collagenous fibroma (desmoplastic fibroblastoma). The patient remains disease-free 4 years after excision.     

Two cases of schwannoma with marked cystic changes

We report two cases of schwannoma displaying marked cystic changes; one in the temporalis muscle and one in the submandibular space. The first patient, a 44-year-old male, presented after complaining of a swelling rapidly increasing in size in the left temporal region. Computed tomography (CT) indicated a low-density area surrounded by soft tissue. Magnetic resonance imaging (MRI) revealed signal hypointensity on T1 weighted imaging and strong signal hyperintensity on T2 weighted imaging. The extirpated tumour specimen measured 58 mm x 58 mm x 30 mm. Histopathological examination identified schwannoma, comprising spindle cell proliferation in a palisading pattern with obvious cystic changes. The second case involved a 46-year-old female who presented with swelling of the right submandibular region. Panoramic radiography and lateral oblique mandible projection, which were used together with conventional sialography of the submandibular gland, revealed the so-called "ball in hand" appearance of the submandibular gland, and contrast-enhanced CT identified a lesion of 30 mm diameter with a well-defined annular margin and homogeneous low-density near the tumour centre. Benign pleomorphic adenoma was suspected, but histopathological examination identified schwannoma, predominantly comprising Antoni B type tissue.     

Endometrial stromal sarcoma located in the myometrium with a low‐intensity rim on T2‐weighted images: Report of three cases and literature review

Endometrial stromal sarcoma (ESS) most commonly grows from the uterine endometrium into the endometrial cavity; it is rarely located in the myometrium alone, where it may resemble degenerated leiomyoma on magnetic resonance imaging (MRI). We present three cases of intramyometrial ESS mimicking degenerated leiomyoma, all of which have a characteristic low‐intensity rim on T2‐weighted images. Histopathological examination revealed the rim to consist of fibrous tissue layers and/or a decrease in free water caused by distortion of myometrial tissue following tumor expansion. ESS should be included in the differential diagnosis of intramyometrial mass with low‐intensity rim on T2‐weighted image, especially if the mass shows degeneration with no or mild intratumoral hemorrhage. J. Magn. Reson. Imaging 2010;31:975–979. ©2010 Wiley‐Liss, Inc.     

Ovarian carcinoma in patients with endometriosis: MR imaging findings

OBJECTIVE: Various types of malignancy can develop in patients with endometriosis. Enhancing mural nodules have been reported as an imaging characteristic of malignant transformations. We evaluated contrast-enhanced MR imaging to determine the optimum sequence to reveal mural nodules and other characteristics of malignant transformations. MATERIALS AND METHODS: We examined 10 patients with pathologically proven ovarian adenocarcinoma in endometriosis and 10 patients (the control group) with ovarian endometrioma suggestive of malignant transformation on the basis of sonographic findings. We analyzed the size and nature of the endometriomas in each patient. We compared four types of contrast-enhanced MR imaging to determine which sequence best revealed mural nodules. RESULTS: In the malignant and control groups, 80% of the cysts with findings suggestive of malignant transformation showed unilateral disease or larger endometrial cysts on the suggestive side than on the contralateral side. High signal intensity on T1-weighted images and low signal intensity on T2-weighted images relative to the myometrium were observed only in two of 10 malignant endometrial cysts and in all control cysts. All malignant endometriomas had small mural nodules with low signal intensity on T1-weighted contrast-enhanced images. Only three benign endometriomas had mural nodules and none of them enhanced. The enhancement of mural nodules was easily seen on dynamic subtraction imaging. CONCLUSION: On the basis of our findings, endometrial cysts with malignant transformation rarely show low signal intensity on T2-weighted images and usually have enhancing mural nodules. Because the enhancement of mural nodules is often difficult to evaluate on conventional T1-weighted images, dynamic subtraction imaging can be valuable.     

Cholesterol granuloma. Review of the literature apropos of a case]

MRI allows the diagnosis of cholesterol granuloma in the presence of a non contrast-enhanced, erosive solid mass of the apex of the petrous bone or middle ear. Cholesterol granuloma has a suggestive low signal intensity on T1 and T2 weighted sequences (cholesterol crystals, haemoglobin degradation products). These specific features eliminate the principal CT differential diagnoses, particularly cholesteatoma. MRI is also useful for follow-up of treatment.     

3.0T磁共振磁敏感加权成像诊断脑发育性静脉畸形

目的 评价磁敏感加权成像(SWI)在诊断脑发育性静脉畸形(DVA)中的临床应用价值.方法 选取采用3.0T超高场磁共振的SWI及常规MR序列(包括自旋回波T_1加权像、快速自旋回波T_2加权像)诊断为脑发育性静脉畸形的24例患者,对SWI及常规MR序列进行分析.结果 24例脑发育性静脉畸形中发生于额叶白质11例,顶叶白质6例,颞叶2例,小脑半球5例.MR平扫显示DVA病灶11例,其中表现为条状流空信号者4例,表现为T_2WI放射状高信号者7例;MR增强检查显示所有病灶,表现为"海蛇头"样强化特征.SWI检查清晰显示所有病灶,表现为"海蛇头"样低信号影.结论 SWI对小静脉病变较敏感,能取代MR增强检查用于脑发育性静脉畸形的诊断和随访.     

The value of MR imaging in distinguishing leiomyomas from other solid pelvic masses when sonography is indeterminate

The differentiation of a uterine leiomyoma from other solid pelvic masses on sonography is usually straightforward. Occasionally, the sonographic appearance of a pedunculated uterine leiomyoma may simulate that of a solid adnexal mass. The purpose of this study was to determine if MR imaging adds specificity to the diagnosis of indeterminate solid pelvic masses visualized with sonography. Nineteen patients were imaged with MR after sonography revealed the presence of a solid pelvic mass adjacent to the uterus but could not be used to determine whether the mass was a leiomyoma or some other type of tumor. The diagnostic criteria for a leiomyoma on MR imaging included (1) the presence of a mass adjacent to the uterus and (2) a mass that was predominantly low signal intensity or isointense compared with normal myometrium on T1-weighted images and predominantly low signal intensity on T2-weighted images. In 11 of 13 patients, the masses that met these MR criteria for leiomyoma were proved to be uterine leiomyomas at surgery. Another mass that met the criteria was shown to be a leiomyoma in the broad ligament; the other was an ovarian fibroma. Of the six cases that did not meet the MR criteria for the diagnosis of leiomyoma, three were proved to be degenerated fibroids, one was squamous cell carcinoma of the cervix, and two were ovarian malignant tumors. Because leiomyomas often have an MR appearance that is distinct from that of solid pelvic malignant tumors, MR imaging can be useful for the diagnosis of some indeterminate solid pelvic masses.     

15例子宫平滑肌瘤MRI征象分析

目的：通过手术病理对照，分析了１５例子宫产滑肌瘤的ＭＲＩ表现。探讨子宫平滑肌瘤的ＭＲＩ征象及诊断意义，材料与方法：１５例患者包括单发者１０例，多发者５例，ＭＲＩ检查采用Ｄｉａｓｏｎｉｃｓ０．３５Ｔ超导成像系统，行横断面和／或矢状面Ｔ１、Ｔ２加权成像，观察ＭＲＩ对子宫肌瘤的定位及定量价值，总结其信号变化规律。结果：ＭＲＩ共发现病灶３５个，病灶发现率８７．５％（手术发现４０个），包括浆膜下１０个，肌内     

PET/CT and MRI of intra-osseous haemangioma of the tibia

Intra-osseous haemangioma is a rare, benign neoplasm that usually involves the vertebrae and craniofacial bones. Furthermore, its occurrence in the long bones is extremely rare. We report the findings of fluorine-18-fludeoxyglucose ((18)F-FDG) positron emission tomography (PET)/CT and MRI in a patient with intra-osseous haemangioma in the proximal tibia, who was initially misdiagnosed as having a malignancy based on (18)F-FDG PET/CT. (18)F-FDG PET/CT showed a well-marginated osteolytic lesion with abnormal FDG uptake. The mass demonstrated low signal intensity on T(1) weighted MRI. On T(2) weighted images, the lesion appeared as a cluster of high signal intensity lobules and showed strong enhancement on contrast-enhanced T(1) weighted images. Surgical curettage was performed and histopathological examination of the excised tissue confirmed a cavernous haemangioma.     

Gossypiboma in abdomen and pelvis: MRI findings in four patients

OBJECTIVE: The purpose of our study was to describe the MRI features of gossypiboma and correlate the MRI findings with the pathologic findings in four patients. CONCLUSION: On MRI, gossypiboma in the abdomen and pelvis manifested as a well-defined mass that showed a peripheral wall of low signal intensity at T1- and T2-weighted imaging and enhancement at contrast-enhanced T1-weighted imaging. The whorled stripes within the central portion were characteristically shown as low signal at T2-weighted imaging, and the serrated contour in the inner border of the peripheral wall was shown at contrast-enhanced T1-weighted imaging. Histopathologically, the peripheral wall showed granulomatous inflammation with massive fibrosis and foam cell and multinucleated giant cell infiltrations, whereas the whorled stripes within the central portion were gauze fibers. If a patient has a history of a previous operation, the possibility of gossypiboma should be suggested when the central whorled stripes or serrated contour in the inner border of the peripheral wall is present at MRI.     

颅内神经元肿瘤的影像诊断

目的 探讨颅内神经元肿瘤的影像学表现,评价CT和MRI对该类肿瘤的诊断价值。方法 经手术不病理证实的神经元肿瘤10例,回顾分析其CT及MRI表现,结果 节细胞胶质瘤3例;中枢神经细胞瘤3例;胚胎发育不良性神经上上皮肿瘤（DNT）3例（7个病灶）,肿瘤外形呈脑回状或结节脑回状,2个局灶性者呈中度强化,其余无明显强化。多纤维组织性婴儿节细胞胶质瘤（DIG）1例,病灶囊变明显,可见钙化,肿瘤实体明显均匀强化,结论 部分神经元肿瘤CT及MRI表现具有一定的特征性,但仅造影像学表现作出诊断是困难的,须结合临床资料,可进一步提高该类肿瘤的诊断正确率。     

Magnetic resonance imaging in aggressive fibromatosis

The magnetic resonance imaging (MRI) features of aggressive fibromatosis in 11 patients (five with recurrent tumour) and its contribution to patient management are described. Tumour signal intensity ranged from being low to isointense with respect to muscle on T1-weighted images while being predominantly of heterogenous increased signal intensity on T2-weighted images. A post-contrast (Gd-DTPA) study demonstrating diffuse tumour enhancement was of value in assessing tumour extent in two patients. CT in six patients and angiography in two patients provided no additional information while tumour relationship to neurovascular structures and extent was better appreciated on MRI. MRI was accurate in predicting resectability in all six patients who had surgery.     

3T磁共振多参数成像胰岛素瘤检出效能初探

目的:评价3T磁共振多参数成像对内源性高胰岛素血症患者胰岛素瘤的检出敏感度,并分析胰岛素瘤在不同序列磁共振的信号特点和对比度.方法:31例内源性高胰岛素血症患者术前行3T磁共振检查,包括T1-Dixon序列、T2-HASTE不压脂序列、T2-BLADE压脂及不压脂序列及自由呼吸多b值DWI序列.两名放射科医师独立地前瞻性分析各序列胰岛素瘤的信号特点及肿瘤与胰腺实质的对比度.结果,31例患者均接受手术,并经病理证实为胰岛素瘤.29例肿瘤通过术前前瞻性阅片准确检出,敏感度为93.5％.肿瘤-胰腺实质主观对比度最高的序列是自由呼吸DWI(b值=800s/mm2),其次是T1-Dixon同相位,而T2WI肿瘤-胰腺实质对比度普遍较低.T1-Dixon压脂相的对比噪声比(CNR)最高.6例肿瘤在T1WI及T2WI对比度均较低,而在DWI上显示为边界清楚的高信号结节.结论:3T磁共振对胰岛素瘤定位能力良好.T1-Dixon同相位和高b值DWI的肿瘤-胰腺实质对比度最高.DWI可协助检出T1及T2信号对比度较低的肿瘤.     

阔韧带平滑肌瘤的影像诊断(附九例报告)

目的 研究阔韧带平没肌瘤的影像诊断。方法 回顾性总结９例经手术和病理证实为阔韧带平滑肌瘤的Ｂ超、ＣＴ及ＭＲＩ表现。结果 ９例Ｂ超检查表现为盆腔内、子宫外实性肿块,呈低回声灶,４例内有斑点状液性暗区或不均匀光点,５例显示包膜,７例边界清晰。８例ＣＴ检查７例表现为实性肿块,边界较清晰,平扫密度较均匀,与子宫肌密度相当或稍低;１例为混合密度灶,可见液化、坏死与囊变;８例增强扫描实性部分均见明显强化,４例     

MR findings of ovarian tumours with cystic components

This article depicts the MR findings of ovarian tumours with cystic components. MRI can predict the cyst contents and evaluate the potential for malignancy when an irregular solid portion or a papillary nodule is observed within the cystic tumour. Post-contrast T1 weighted MRI is helpful for the identification of solid areas that enhance. Fat suppression imaging is useful for differentiation between mature cystic teratoma and other pathology. Fat suppressed post-contrast T1 weighted MRI may demonstrate contrast enhancement, reflecting inflammatory or neoplastic processes in the pelvis.