Ovarian fibromatosis: magnetic resonance imaging findings with pathologic correlation

Ovarian fibromatosis is a rare benign nonneoplastic condition with ovarian enlargement in young women and characterized by a proliferation of collagen-producing spindle cells surrounding normal ovarian structures. We reported magnetic resonance findings of a case that the affected ovarian parenchyma with follicles was surrounded by very low intense thick fibrous tissue on T2-weighted images such as "black garland" around the ovary. The magnetic resonance findings well reflected the pathological feature of the disease and may be diagnostic.     

MR imaging in fibromatosis: results in 26 patients with pathologic correlation

Fibromatoses are a diverse group of soft-tissue lesions that have been inconsistently categorized and treated. The purpose of our study was to establish the range of appearances of fibromatoses on MR images and perform a pathologic correlation to explain the variable signal-intensity patterns. During a 3-year period, 26 patients with deep fibromatoses were examined with MR. The MR images were evaluated for signal-intensity characteristics, and findings were correlated retrospectively with the pathologic diagnoses. The results showed that the MR appearance of fibromatoses is similar to that of other soft-tissue lesions, and the signal intensities vary greatly from lesion to lesion and within lesions themselves. The fibromatoses were either hyperintense, isointense, hypointense, or of mixed signal intensity relative to adjacent skeletal muscle. The hypointense areas appear to be zones of hypocellularity and dense collagen deposition. Microscopically all of the lesions invaded adjacent structures, but the MR appearances of the margins varied and were judged to be well demarcated (n = 14), intermediate (n = 5), or poorly demarcated (n = 6). Our experience shows that fibromatoses have a variable MR appearance no different from that of other soft-tissue lesions, and this variability reflects the composition and cellularity of the lesions.     

MR imaging of soft-tissue hemangiomas: correlation with pathologic findings

Soft-tissue hemangiomas have been described in MR imaging, but a histopathologic correlation to better understand the MR appearance has not been reported. Five patients with intramuscular soft-tissue hemangiomas were imaged in orthogonal planes on a 1.5-T system with spin-echo (SE) short-TR/TE sequences (600/20) and long-TR/TE sequences (2500/20-80). Complete intact surgical specimens were obtained, and gross and histopathologic findings were compared with MR findings. A striated-septated configuration with a high signal intensity on long-SE sequences (TE greater than 75 msec) correlated with endothelial-lined vascular channels separated by fibrous and/or fatty linear strands. An awareness of the morphologic MR pattern of soft-tissue hemangiomas may aid in recognition of these lesions.     

CT and MR imaging findings of xanthogranulomatous cholecystitis: correlation with pathologic findings

The aim of this study was to evaluate CT and MRI findings in xanthogranulomatous cholecystitis (XGC) and to correlate the imaging findings with various pathologic parameters. The study included 13 patients with histopathologically confirmed XGC. The CT (n=13) and MRI (n=5) obtained in these patients were evaluated retrospectively. On CT, low-attenuation areas in the wall of XGC correlated with foam and inflammatory cells or necrosis and/or abscess in XGC. Areas of iso- to slightly high signal intensity on T2-weighted images, showing slight enhancement at early phase and strong enhancement at last phase on dynamic study, corresponded with areas of abundant xanthogranulomas. Areas with very high signal intensity on T2-weighted images without enhancement corresponded with necrosis and/or abscesses. Luminal surface enhancement (LSE) of gallbladder wall represented preservation of the epithelial layer. The early-enhanced areas of the liver bed on dynamic CT and MR images corresponded with accumulation of inflammatory cells and abundant fibrosis. Our results indicate that CT and MRI findings correlate well with the histopathologic findings of XGC.     

Primary sclerosing cholangitis: MR imaging findings with pathologic correlation.

OBJECTIVE: The purpose of this study was to evaluate MR imaging findings of primary sclerosing cholangitis, to compare them with histopathologic findings, and to determine if these findings help differentiate primary sclerosing cholangitis from other disorders that result in end-stage liver disease. MATERIALS AND METHODS: MR imaging was performed in 40 patients (27 men, 13 women; age range, 13-72 years; mean, 47 years) with primary sclerosing cholangitis over a 9-year period. In 16 patients who underwent orthotopic hepatic transplantation and in seven patients who underwent needle biopsy, correlation was made between MR imaging and pathologic findings. RESULTS: Focal signal changes in the liver parenchyma were seen on T2-weighted images as peripheral wedge-shaped zones of increased signal intensity in 29 patients (72%), as a reticular pattern in 15 patients (38%), and as periportal edema in 16 patients (40%). Lobar atrophy involved the right lobe in three patients (8%) and the left lobe in 11 patients (28%); hypertrophy of the caudate lobe was seen in nine patients (23%). Features of portal hypertension were seen in 14 patients (35%). Histologic assessment showed zones of segmental atrophy and scarring on the periphery of the liver. CONCLUSION: Peripheral wedge-shaped areas of high T2 signal intensity and dilatation of bile ducts are characteristic MR features of primary sclerosing cholangitis. Pathologic correlation suggests that these features may be related to underlying perfusion changes and bile duct inflammation in patients with primary sclerosing cholangitis.     

Brachial plexus: correlation of MR imaging with CT and pathologic findings

Thirty-two patients with symptoms referable to the brachial plexus were evaluated with magnetic resonance (MR) imaging. Sixteen patients had undergone concurrent computed tomography (CT). MR imaging demonstrated normal findings in 16, 12 neoplasms, three cases of trauma, and one case of possible neural edema. Of the 16 patients with normal findings on MR images, eight had CT scans that were also normal. In one patient, MR images showed that the "mass" seen on CT was actually a tortuous blood vessel. In six of the 12 cases of neoplasm in which CT scans were available, MR imaging revealed more extensive disease. In the other six cases of tumor, MR imaging provided sufficient clinical information to obviate the need for CT or any other imaging modality. MR imaging provided definitive diagnoses in the three cases of trauma without further imaging. In one patient with paresthesia, MR imaging showed high signal intensity of the nerves on T2-weighted images, which was compatible with neural edema. A concurrent CT scan was normal.     

MR imaging of uterine carcinoma: correlation with clinical and pathologic findings

Thirteen patients with clinical stages I and II endometrial carcinoma were examined with magnetic resonance (MR) imaging before surgery. Depth of invasion and stage of disease were assessed, and the results were compared with those from MR images of the surgical specimens and pathologic findings. Staging with MR imaging was accurate in 11 of 13 patients (85%). Our results agree with previous reports that MR imaging is an accurate, noninvasive method of assessing depth of myometrial invasion and cervical involvement. We anticipate that MR imaging will have an increasing role in treatment of patients with endometrial carcinoma.     

Intramuscular vascular malformations of an extremity: findings on MR imaging and pathologic correlation

Objective. To analyze the findings of intramuscular vascular malformations of an extremity on MR imaging and to correlate these findings with histopathologic examination. Design and patients. The findings on MR imaging and the medical records of 14 patients with an intramuscular vascular malformation of the extremity were retrospectively studied. All patients underwent surgical excision. Diagnoses were based on the results of pathologic examination. Findings on MR imaging were noted and correlated with the histopathologic findings. Results. Intramuscular vascular malformations of an extremity showed multi-septate, honeycomb, or mixed appearance on MR imaging. Multi-septate areas correlated with dilated and communicating vascular spaces with flattened endothelium. Honeycomb areas corresponded to vascular spaces with inconspicuous small lumina and thickened vascular walls. Areas of increased signal intensity on T2-weighted images were found in all intramuscular vascular malformations. Infiltrative margins were more commonly seen in intramuscular lymphaticovenous malformations. Adherence to neurovascular structures and orientation of the lesion along the long axis of the affected muscle were more commonly seen in intramuscular venous malformations. Conclusions. Intramuscular vascular malformations showed either a multi-septate, honeycomb, or mixed appearance, reflecting the size of the vascular spaces and the thickness of the smooth muscles of the vessel walls. Prediction of the subtype of an intramuscular vascular malformation of an extremity on MR imaging seems to be difficult, although there are associated findings that may be helpful in the differential diagnosis of each subtype. Received: 19 January 1999 Revision requested: 4 May 1999 Revision received: 23 June 1999 Accepted: 29 June 1999     

肝腺瘤:MRI影像学表现与病理亚型的相关性研究

目的研究肝腺瘤的MRI影像学表现与病理亚型的相关性。材料与方法本回顾性研究获得伦理委员会批准。免除受试者知情同意。由2名放射学专家对61个病灶(48例病人,中位年龄36岁)分别独立进行MRI分析。2名观察者就病变的形态和信号特点的影像特征达成共识。所     

MR imaging of endometrial stromal sarcoma: correlation with pathologic findings.

OBJECTIVE: This study describes MR imaging of eight patients with endometrial stromal sarcoma and correlates the imaging findings with histopathologic findings. To our knowledge, the radiologic findings of this entity have not been reported in the literature. CONCLUSION: Endometrial stromal sarcoma typically presents with extensive myometrial involvement, which is either sharply demarcated or diffusely infiltrative. Bands of low signal intensity are observed within the areas of myometrial involvement on T2-weighted images. These bands correspond to the preserved bundles of myometrium on pathologic examination. Tumor extension along the vessels or ligaments is another characteristic of MR imaging of endometrial stromal sarcoma.     

Immature teratoma of the ovary: correlation of MR imaging and pathologic findings

The objectives of this study were to describe MR imaging findings of immature teratoma and to correlate imaging findings with histopathologic findings. The MR findings of ten patients (age range 12–29 years, mean age 19.0 years) with pathologically proven immature teratoma were retrospectively reviewed for tumor size, presence and characteristics of fatty content, presence and characteristics of solid components, and presence of ascites and implants. The MR findings were compared with gross (n=3) and microscopic (n=10) findings. Comparisons between relative amounts of solid components and histologic grades were evaluated by Spearman rank-order correlation. On MR images all lesions appeared to be fat-containing tumors with solid components consisting of numerous cysts of various sizes. Solid tissue exhibited a wide variety of signal intensities on T2-weighted images. Punctate foci of fat were identified in all lesions, whereas fatty fluid was observed only in two. Predominant fluid content exhibited signal intensities similar to simple fluid in nine lesions. Ascites was observed in six lesions, and peritoneal dissemination in three. Pathologic studies confirmed scattered foci of adipose tissue in the solid portions of all cases, and revealed numerous cystic structure formations in these solid components. The correlation coefficient between the amount of solid tissue and the tumor grade was not significant (r_s=0.266). The MR images of immature teratoma tended to show aqueous fluids and the solid components consisting of numerous cysts with punctate foci of adipose tissue, whereas predominant fluid is sebaceous fluid in the vast majority of mature cystic teratomas. Electronic Publication     

Infarcted regenerative nodules in cirrhosis: CT and MR imaging findings with pathologic correlation

OBJECTIVE. The purpose of this article is to present the imaging findings and correlative pathologic findings of infarcted regenerative nodules in the cirrhotic liver. CONCLUSION. Infarcted regenerative nodules exhibit a spectrum of imaging appearances in the cirrhotic liver and can resemble hypovascular hepatocellular carcinoma or other neoplasms on CT and MR imaging. Although uncommon, this abnormality must be included in the differential diagnosis of focal liver lesions in patients with cirrhosis, particularly in patients with a history of substantial gastrointestinal bleeding. Serial imaging may help differentiate these lesions from malignant tumors.     

Thyroid masses: MR imaging and pathologic correlation

The authors explored the capability of high-field-strength surface coil magnetic resonance (MR) imaging in disclosing the gross pathologic characteristics of thyroid masses (especially pseudocapsular and hemorrhagic degeneration). Twenty-four patients were examined, including 12 with papillary carcinoma, eight with adenoma, and four with adenomatous goiter. All patients underwent surgery within 2 days after MR imaging. Specimens were cut and correlated directly with MR images. The appearance of the pseudocapsule was classified into four types: A, intact and even thickness around the tumor; B, only partially present or even absent; C, intact but with uneven thickness; D, partially destroyed by tumor. MR imaging findings corresponded precisely with those of gross pathologic examination in all cases but four of adenoma. Type A pseudocapsules were found only in adenoma and type D only in papillary carcinoma. Although the number of cases in the series was limited, the authors conclude that MR images reflect gross pathologic findings well and that some characteristic findings are suggestive of benign or malignant disease.     

胶质肉瘤的影像表现与病理对照

目的：总结分析胶质肉瘤的影像学表现及病理学特征。方法：回顾性分析我院2003年～2009年收治7例经手术病理证实的胶质肉瘤的影像学资料,其中6例术前行CT检查,4例行MRI检查,并与病理结果进行对照分析。结果：7例均位于幕上大脑半球。3例病灶CT显示为混杂密度,2例为囊实性病灶,1例呈稍高密度实性肿块。4例MRI在T1WI上均以低信号为主,T2WI为混杂稍高信号或高信号;1例侵及胼胝体膝部。增强后呈不均匀强化,瘤周水肿轻微或无瘤周水肿。光镜显示：肿瘤细胞密集,呈大片状排列,异形性较明显,可见多核瘤巨细胞和核分裂现象,部分区域有明显坏死。免疫组化标志：波形蛋白（＋＋）,神经胶质原纤维酸性蛋白（＋）、S-100（＋）、上皮膜抗原（＋）。结论：胶质肉瘤影像学表现有一定的特点,CT、MRI检查有助于该病的诊断和指导治疗。     

Benign versus malignant hepatic nodules: MR imaging findings with pathologic correlation.

According to the currently used nomenclature, there are only two types of hepatocellular nodular lesions: regenerative lesions and dysplastic or neoplastic lesions. Regenerative nodules include monoacinar regenerative nodules, multiacinar regenerative nodules, cirrhotic nodules, segmental or lobar hyperplasia, and focal nodular hyperplasia. Dysplastic or neoplastic nodules include hepatocellular adenoma, dysplastic foci, dysplastic nodules, and hepatocellular carcinoma (HCC). Many of these types of hepatic nodules play a role in the de novo and stepwise carcinogenesis of HCC, which comprises the following steps: regenerative nodule, low-grade dysplastic nodule, high-grade dysplastic nodule, small HCC, and large HCC. State-of-the-art magnetic resonance (MR) imaging facilitates detection and characterization in most cases of hepatic nodules. State-of-the-art MR imaging includes single-shot fast spin-echo imaging, in-phase and opposed-phase T1-weighted gradient-echo imaging, T2-weighted fast spin-echo imaging with fat saturation, and two-dimensional or three-dimensional dynamic multiphase contrast material-enhanced imaging.     

Castleman disease of the parotid gland: MR imaging findings with pathologic correlation

A case of a hyaline-vascular type of Castleman disease originating in the parotid gland in which MR-pathologic correlation was obtained was presented. T1- and T2-weighted MR images showed a well-circumscribed 6 cm mass of intermediate signal intensity with hypointense branching structures within the mass. Gadolinium-enhanced dynamic MR imaging demonstrated a marked homogeneous enhancement of the mass with a peak enhancement at 60 s after intravenous gadolinium injection, whereas the branching structures showed a delayed enhancement to the degree of the mass at equilibrium phase. MR-pathologic correlation revealed that the branching structures corresponded to thick fibrotic bundles in the mass. A homogeneously enhancing well-circumscribed parotid mass with hypointense branching structures may indicate Castleman disease.     

Prostate cancer: correlation of MR imaging and MR spectroscopy with pathologic findings after radiation therapy-initial experience

PURPOSE: To prospectively evaluate magnetic resonance (MR) imaging and MR spectroscopy for depiction of local prostate cancer recurrence after external-beam radiation therapy, with step-section pathologic findings as the standard of reference. MATERIALS AND METHODS: Study received institutional approval, and written informed consent was obtained. Study was compliant with Health Insurance Portability and Accountability Act. Sextant biopsy, digital rectal examination, MR imaging, MR spectroscopy, and salvage radical prostatectomy with step-section pathologic examination were performed in nine patients with increasing prostate-specific antigen levels after external-beam radiation therapy. MR imaging criterion for tumor was a focal nodular region of reduced signal intensity at T2-weighted imaging. MR spectroscopic criteria for tumor were voxels with choline (Cho) plus creatine (Cr) to citrate (Cit) ratio ([Cho + Cr]/Cit) of at least 0.5 or voxels with detectable Cho and no Cit in the peripheral zone. Sensitivity and specificity of sextant biopsy, digital rectal examination, MR imaging, and MR spectroscopy were determined by using a prostate sextant as the unit of analysis. For feature analysis, MR imaging and MR spectroscopic findings were correlated with step-section pathologic findings. RESULTS: MR imaging and MR spectroscopy showed estimated sensitivities of 68% and 77%, respectively, while sensitivities of biopsy and digital rectal examination were 48% and 16%, respectively. MR spectroscopy appears to be less specific (78%) than the other three tests, each of which had a specificity higher than 90%. MR spectroscopic feature analysis showed that a metabolically altered benign gland could be falsely identified as tumor by using MR spectroscopic criteria; further analysis of MR spectroscopic features did not lead to improved MR spectroscopic criteria for recurrent tumor. CONCLUSION: In summary, MR imaging and MR spectroscopy may be more sensitive than sextant biopsy and digital rectal examination for sextant localization of cancer recurrence after external-beam radiation therapy.