共查询到20条相似文献,搜索用时 31 毫秒
1.
Struma ovarii: appearance on MR images 总被引:2,自引:0,他引:2
I. Joja T. Asakawa A. Mitsumori T. Nakagawa Y. Hiraki T. Kudo M. Ando N. Akamatsu 《Abdominal imaging》1998,23(6):652-656
Background: The purpose of this multi-institutional study was to examine the appearance of struma ovarii on magnetic resonance (MR) images.
Methods: MR images of 12 patients with histologically proven struma ovarii were retrospectively reviewed. All patients underwent T1-weighted
and T2-weighted imaging. Contrast-enhanced T1-weighted images with Gd-DTPA were available in 10 patients. The following determinations
were made: tumor morphology, signal intensities, contrast-enhancement effects of solid components with Gd-DTPA, and comparison
of MR images with resected specimens.
Results: All 12 patients had both cystic and solid components, with a multilobulated surface and thickened septa. Signal intensities
on T1-weighted images were mainly low, partly intermediate to high, or high, and those on T2-weighted images were mainly high,
with different signal intensities. Contrast-enhancement effects were marked or moderate. The contents that showed low signal
intensities on T1-weighted images and signal voids or low signal intensities on T2-weighted images were viscid gelatinous
materials.
Conclusions: A multicystic tumor with a solid component, a multilobulated surface, and signal intensities that indicate the presence of
viscid gelatinous materials appear to be a characteristic MR finding of struma ovarii.
Received: 10 April 1997/Accepted after revision: 7 July 1997 相似文献
2.
Plain and gadolinium-DTPA-enhanced MR imaging of hepatocellular carcinoma treated with transarterial chemoembolization 总被引:12,自引:0,他引:12
M. Castrucci S. Sironi F. De Cobelli M. Salvioni A. Del Maschio 《Abdominal imaging》1996,21(6):488-494
Background: To assess unenhanced and gadolinium-enhanced magnetic resonance (MR) imaging patterns of hepatocellular carcinoma (HCC) treated
with transarterial chemoembolization (TACE).
Methods: Thirty-two patients with 48 HCC lesions underwent MR imaging before and 15 days after TACE. Fifteen lesions were then surgically
resected. The remaining 33 lesions were not removed and were followed up with MR imaging at 3, 6, 12, and 18 months after
treatment. Spin echo (SE) T1- and T2-weighted and gadolinium-enhanced SE T1-weighted sequences were employed. Qualitative
evaluation of signal intensity pattern of the treated lesions was performed in all cases. Histological evaluation and selective
hepatic arteriography were considered the gold standard of the study for the 15 resected lesions and the 33 unresected lesions,
respectively.
Results: On follow-up enhanced T1-weighted images of the 15 resected lesions, seven showed no area of enhancement corresponding to
complete necrosis at histologic examination. The remaining eight resected lesions showed areas of enhancement; in six of these
cases, viable tumor tissue was found at histology; in the other two lesions, histologic examination revealed the presence
of complete tumor necrosis. In the group of resected lesions, T2-weighted images showed no pattern characteristic of necrosis.
In 24 of 33 unresected lesions, loss of enhancement on follow-up enhanced T1-weighted images was a characteristic finding,
which correlated to devascularization at arteriography. Of these 24 lesions, 17 were completely hypointense on follow-up T2-weighted
images; the remaining seven showed small foci of hyperintensity. The other nine unresected lesions showed enhanced portions
on follow-up enhanced T1-weighted images, which corresponded to hyperintense areas on T2-weighted images. These findings correlated
to persistence of hypervascular areas at arteriography.
Conclusion: Gadolinium-enhanced T1-weighted MR imaging is a reliable method for evaluating the outcome of TACE treatment and is more
accurate than unenhanced T2-weighted MR imaging.
Received: 2 June 1995/Accepted: 18 July 1995 相似文献
3.
Focal nodular hyperplasia of the liver: detection and characterization with plain and dynamic-enhanced MRI 总被引:2,自引:0,他引:2
Mortelé KJ Praet M Van Vlierberghe H de Hemptinne B Zou K Ros PR 《Abdominal imaging》2002,27(6):0700-0707
Background: We compared nonenhanced and dynamic gadolinium (Gd)–enhanced magnetic resonance imaging (MRI) appearances of hepatic focal
nodular hyperplasia (FNH) as depicted with breath-hold MR sequences and assessed the detectability of the individual MR sequences
used. Methods: We retrospectively reviewed 48 consecutive patients with FNH. All patients underwent nonenhanced (T1 fast low-angle shot
[FLASH] and T2 half-Fourier acquisition [HASTE]) and dynamic Gd-enhanced (T1 FLASH) MRI between December 1997 and March 2000.
Individual MR sequences were analyzed separately for number of lesions, signal intensity features, dynamic enhancement pattern,
and the presence and enhancement profile of a central scar. Ninety-five percent confidence intervals of absolute discrepancy
were calculated to define differences in lesion detection. Results: Seventy-seven lesions were found in 48 patients. Nonenhanced FLASH imaging depicted 59 (76.6%) lesions in 45 patients. HASTE
images showed 55 (71.4%) lesions in 44 patients. On T1- and T2-weighted images, lesions appeared predominantly hypointense
(69.5%) and hyperintense (72.7%), respectively. Arterial and portal venous dominant phase Gd-enhanced MRI demonstrated all
77 lesions (100%), most of which showed hypervascular (94.8%), homogeneous (97.4%), and incomplete (except the central scar:
58.4%) enhancement in the arterial phase. Portal venous phase images showed lesion isointensity (50.6%) or moderate hyperintensity
(46.8%) with complete enhancement (central scar: 94.8%). A central scar was detected on nonenhanced T1-weighted images (hypointense:
100%), T2-weighted images (hyperintense: 100%), arterial phase (hypointense: 59.7%) and portal venous phase (hyperintense:
71.4%) Gd-enhanced images in 78%, 69.1%, 77.9%, and 75.3% of tumors, respectively. Conclusion: Arterial and portal venous phase Gd-enhanced T1-weighted sequences are superior to nonenhanced images in the detection of
FNH. Typical MRI appearances include hypointensity on T1-weighted and hyperintensity on nonenhanced T2-weighted images. Most
commonly, FNH shows a homogeneous (without scar) and strong enhancement during the arterial phase, with lesion isointensity
or slight hyperintensity during the portal venous phase.
Received: 15 May 2001/Revision accepted: 22 August 2001 相似文献
4.
Background: To elucidate the imaging characteristics of well-differentiated hepatocellular carcinomas (HCCs) on ultrasonography (US),
computed tomography (CT), and magnetic resonance (MR) imaging.
Methods: Ultrasonograms, CTs, and MR images of 18 histopathologically proven well-differentiated HCCs in 15 patients were reviewed.
The findings of these images were correlated with histopathologic findings.
Results: On US, seven tumors were depicted as a hyperechoic area and eight as a hypoechoic area. Three tumors were not visualized.
On precontrast CT, four tumors were depicted as a low-density area, but 14 were not visualized. On conventional contrast-enhanced
CT, 12 tumors were depicted as a low-density area but six were not visualized. On T1-weighted MR images, 10 tumors had high
signal intensity and two had low signal intensity. Six tumors were not visualized. On T2-weighted MR images, five tumors had
high signal intensity and two had low signal intensity. Eleven tumors were not visualized. Tumors with fatty change and/or
clear cell formation were frequently hyperechoic on US and hyperintense on T1-weighted MR images.
Conclusions: Well-differentiated HCCs show different findings on US, CT, and MR imaging. Therefore, reliable diagnosis of well-differentiated
HCCs by these imaging techniques may be difficult.
Received: 29 April 1998/Revision accepted: 15 July 1998 相似文献
5.
Nodular regenerative hyperplasia of the liver in Budd–Chiari syndrome: CT and MR features 总被引:1,自引:0,他引:1
We report the imaging findings of spiral computed tomography (CT), magnetic resonance (MR) imaging, and MR angiography in
a patient with nodular regenerative hyperplasia of the liver associated with Budd–Chiari syndrome. Spiral CT showed multiple
enhancing nodules during the hepatic arterial and portal venous phases. MR images showed multiple hyperintense nodules on
T1-weighted images and hypointense or isointense nodules on T2-weighted images. MR angiography showed thrombotic occlusion
of three hepatic veins, suggesting Budd–Chiari syndrome.
Received: 25 June 1999/Revision accepted: 22 September 1999 相似文献
6.
Small hepatocellular carcinoma: differentiation from adenomatous hyperplasia with color Doppler US and dynamic Gd-DTPA-enhanced MR imaging 总被引:4,自引:0,他引:4
Background: To investigate the usefulness of color Doppler ultrasound (US) and dynamic Gd-DTPA-enhanced magnetic resonance (MR) imaging
in the differentiation of small hepatocellular carcinoma (HCC) and adenomatous hyperplasia (AH).
Methods: Thirty-eight small (3 cm or less) nodular lesions (in 38 cirrhotic patients) with US features consistent with HCC underwent
evaluation with color Doppler US and MR imaging. Breath-hold T1-weighted rapid acquisition spin echo MR sequence after bolus
injection of 0.1 mmol/kg gadopentetate dimeglumine was used to evaluate dynamic enhancement. US-guided tissue-core percutaneous
biopsy established the diagnosis: HCC in 28 cases and AH in 10.
Results: Color signals with pulsatile or continuous Doppler spectrum were demonstrated in 19 of 28 HCCs (68%) but in none of the AHs.
Although there was considerable overlap in signal intensity between HCC and AH on both unenhanced T1- and T2-weighted images,
early enhancement on breath-hold T1-weighted images obtained 40 s after starting contrast administration was observed in 22
of 28 HCCs (79%) but in none of the AHs. In 26 of 28 HCCs (93%), pulsatile or continuous flow at color Doppler US, early enhancement
at dynamic MR imaging, or both were observed.
Conclusion: Findings with color Doppler US and dynamic Gd-DTPA-enhanced MR imaging enable a reliable distinction between small HCC and
AH.
Received: 8 August 1994/Accepted after revision: 27 January 1995 相似文献
7.
R. A. Huch Böni C. Meyenberger J. Pok Lundquist F. Trinkler U. Lütolf G. P. Krestin 《Abdominal imaging》1996,21(4):345-352
Background: To compare endorectal coil magnetic resonance imaging (MRI) with body coil MRI in detecting local recurrence of gynecologic
tumors and prostate and rectal cancers.
Methods: Forty-six patients with suspected recurrent pelvic malignancies (13 gynecologic, 15 prostatic, and 18 anorectal primaries)
were enrolled in the study. Axial T1- and T2-weighted body coil images and T2- and contrast-enhanced T1-weighted axial endorectal
coil images were obtained on a 1.5 T system. Results of the MR examinations were compared with histogical findings and follow-up
examinations with respect to the diagnostic accuracy and diagnostic confidence for assessment or exclusion of local recurrence.
Results: Recurrent disease was histologically confirmed in eight patients with primary gynecologic malignancies, seven with suspected
prostatic recurrence, and seven with suspected anorectal recurrence. Overall, accuracy of body coil MRI was 67% for gynecologic
tumors, 36% for prostatic recurrences, and 59% for rectal recurrences. T2- and contrast-enhanced T1-weighted endorectal sequences
yielded similar results, with an accuracy of 73% for depiction of gynecologic recurrence, 77% for prostatic recurrence, and
77% for rectal recurrence. The difference in accuracy between body coil and endorectal coil examinations was statistically
significant (p < 0.05) only for prostatic cancer. Diagnostic confidence was, however, significantly improved (p < 0.05) in all tumors (T2-weighted endorectal coil examination was superior to T2-weighted body coil images in 71% of cases).
Conclusion: Although the results of endorectal coil MRI are only slightly superior to those of body coil MRI for the detection of recurrent
gynecologic and anorectal tumors, diagnosis can be made with greater diagnostic confidence in many cases. For detection of
prostatic recurrence, endorectal MRI is highly recommended.
Received: 27 April 1995/Accepted: 17 June 1995 相似文献
8.
We describe the unusual magnetic resonance (MR) findings of a case of Wilson's disease (WD) in an asymptomatic 2-year-old
girl. Preenhanced computed tomography revealed multiple hyperdense areas in the liver. These lesions were hyperintense on
T1-weighted and hypointense on T2-weighted MR images, results that might be ascribed to the paramagnetism of copper deposited
in liver at a relatively early stage of the disease before severe liver cirrhosis had evolved.
Received: 9/10/96/Accepted: 10/16/96 相似文献
9.
Background:
To determine the magnetic resonance (MR) features of hepatocellular carcinoma (HCC) with associated bile duct involvement.
Methods:
MR examinations of six patients (mean age, 62 years) demonstrating bile duct involvement due to HCC were retrospectively reviewed and compared to surgical and pathologic findings.
Results:
Three of the tumors were solitary, and three were multifocal. In two patients, MR showed direct biliary duct invasion by tumor. On T1-weighted MR images, four tumors were hypointense compared to the liver and two were isointense. On T2-weighted MR images, four tumors were hyperintense, and two were isointense. The two tumors studied with dynamic T1-weighted MR images obtained after intravenous administration of a gadolinium chelate, displayed enhancement similar to that of the liver. There was no evidence of a tumor capsule on either unenhanced or enhanced MR images. Intrahepatic bile duct dilatation was seen in five patients. The extrahepatic bile duct was normal in all cases.
Conclusion:
Although rare, HCC should be included when considering the etiology of intrahepatic bile duct obstruction. Imaging features suggestive of the diagnosis by MR include intrabiliary tumor or bile duct obstruction with an associated hepatic mass. 相似文献
10.
Fan-shaped hepatic parenchymal damage after ethanol injection therapy for hepatocellular carcinoma: MRI appearances 总被引:2,自引:0,他引:2
T. Fujita K. Honjo K. Ito T. Arita S. Koike K. Takano S. Tamura T. Matsumoto N. Matsunaga 《Abdominal imaging》1999,24(1):56-60
Background: T1- and T2-weighted magnetic resonance (MR) images frequently show fan-shaped areas of hypo- or hyperintensity in the hepatic
parenchyma adjacent to a treated hepatocellular carcinoma after percutaneous ethanol injection (PEI) therapy. These areas
correspond to abnormal contrast enhancement on serial dynamic MR images. The purpose of the present study was to describe
the location, appearance, and frequency of these abnormalities because it is important to understand these entities for the
correct assessment of therapeutic efficacy.
Methods: MR imaging including a multisection dynamic study was performed in 20 consecutive patients with hepatocellular carcinoma
treated with PEI therapy. We retrospectively evaluated the presence of fan-shaped hypointensities adjacent to treated tumors
in the liver parenchyma on T1-weighted images and hyperintensities on T2-weighted images and corresponding fan-shaped contrast
enhancement on both arterial-dominant and delayed-phase dynamic MR images. We review the location, appearance, and frequency
of these findings, and we discuss the possible causes on the basis of pathologic examinations.
Results: Seven (35%) of the 20 patients showed fan-shaped hyperintense areas adjacent to the treated tumors on T2-weighted images.
These areas showed isointensity in five patients and hypointensity in two patients on T1-weighted images. Of these seven patients,
one (14%) underwent the MR imaging within 1 month after the completion of PEI therapy, and six (86%) had it 2–9 months after
the completion of PEI therapy (mean = 6 months). In all seven patients, fan-shaped hyperperfusion abnormalities corresponding
to these areas of hyperintensity on T2-weighted images were seen on both arterial-dominant and delayed-phase dynamic MR images.
Pathologically, the coagulative necrosis of the hepatocytes with sinusoidal dilatation and the restoration by the development
of fibrous tissue were seen in these fan-shaped areas.
Conclusion: The fan-shaped areas of abnormal intensity on T1- and T2-weighted images and contrast enhancement on dynamic MR images seem
to be attributable to pathologic changes in the normal liver parenchyma induced by the toxic reaction of ethanol. Awareness
of the occurrence of such abnormalities in the peripheral liver parenchyma adjacent to the treated tumor is important for
the correct assessment of therapeutic efficacy.
RID="ID="<e5>Correspondence to:</e5> T. Fujita
Received: 24 June 1997/Accepted after revision: 22 October 1997 相似文献
11.
目的:分析肝脏局灶性结节增生(FNH)的平扫和动态增强的MRI表现及诊断价值,提高FNH诊断的准确率。方法:回顾性分析15例(16个病灶)经病理证实的FNH的平扫及动态增强MRI表现。结果:16个病灶于T1WI呈略低信号或等信号,T2WI呈略高信号或等信号。增强扫描动脉期呈明显强化,在门脉期及延迟期呈等或略高强化。5个病灶在平扫MRI上显示中央瘢痕,11个病灶在动态增强MRI上显示中央瘢痕,均见延迟强化。结论:平扫和动态增强MRI检查能较全面显示FNH的病理特征和血供特点,明显地提高与其他富血管恶性肿瘤的鉴别诊断能力。 相似文献
12.
Hiromi Ono Masayuki Kanematsu Hiroki Kato Hiroshi Toyoki Yoh Hayasaki Tatsuro Furui Ken-ichirou Morishige Yuichiro Hatano 《Abdominal imaging》2014,39(4):797-801
A 69-year-old postmenopausal female with a spontaneously occurring uterine pyomyoma was described with emphasis on the MR imaging findings. On unenhanced T1- and T2-weighted MR images, a huge mottled mass suspected to contain blood products, necrotic tissue, or purulent or viscous fluid was demonstrated within anterior myometrial wall of uterine body. The mass was surrounded by a peripheral rim that was hyperintense on T1-weighted images and hypointense on T2-weighted images. On gadolinium-enhanced MR images, most of the mass was unenhanced, but the peripheral rim was equally enhanced with the surrounding myometrium. Pathological examination revealed an intramural uterine pyomyoma surrounded by fibrous capsules with abundant lymphocytes and neutrophils. Our findings indicate that pyomyoma should be considered when MR images demonstrate a myometrial cystic lesion accompanied by a peripheral rim. 相似文献
13.
MR imaging of cervical carcinoma: comparison among T2-weighted,dynamic, and postcontrast T1-weighted images with histopathological correlation 总被引:4,自引:0,他引:4
K. Tsuda T. Murakami H. Kurachi H. Ogawa H. Oi A. Miyake Y. Narumi H. Nakamura 《Abdominal imaging》1997,22(1):103-107
Background: To identify the reasons for misdiagnosis of the degree of stromal invasion by uterine cervical cancer with various magnetic
resonance sequences.
Methods: T2-weighted, dynamic, and postcontrast T1-weighted images were obtained in the sagittal plane in 20 patients with uterine
cervical cancer. After evaluating these sequences for the degree of stromal invasion, histologic specimens were directly correlated
with these images.
Results: The degree of stromal invasion was correctly diagnosed in 15 of the 20 cases on T2-weighted images, in 12 on dynamic images,
and in eight on postcontrast T1-weighted images. All misdiagnoses were due to overestimation. Histologically, peritumoral
stroma showed inflammation or edema in two patients, whereas no histological abnormality was found in the other patients.
A hyperintense rim, i.e., a peritumoral enhanced ring-shaped structure, was observed on the enhanced images of five patients.
The hyperintense rim corresponded to the periphery of the tumor in three patients and to the cervical stroma in two patients.
Conclusion: T2-weighted images permitted the most accurate evaluation of stromal invasion by uterine tumors. Overdiagnosis may be due
to an abnormal intensity of the cervical stroma, which was observed more frequently on dynamic and postcontrast T1-weighted
images than on T2-weighted images.
Received: 10 November 1995/Accepted after revision: 13 March 1996 相似文献
14.
Detection of lymph-node metastases in patients with gastric carcinoma: comparison of three MR imaging pulse sequences 总被引:9,自引:0,他引:9
Kato M Saji S Kanematsu M Fukada D Miya K Umemoto T Kunieda K Sugiyama Y Takao H Kawaguchi Y Takagi Y Kondo H Hoshi H 《Abdominal imaging》2000,25(1):25-29
Background: To compare the diagnostic accuracy of magnetic resonance (MR) images obtained with three different pulse sequences for lymph-node
metastases in patients with gastric cancer.
Methods: T1-weighted spin-echo (SE), breath-hold T2-weighted fast SE, and triphasic gadolinium-enhanced dynamic gradient-recall-echo
(GRE) MR images obtained in 16 patients with gastric carcinoma were retrospectively reviewed. Regional lymph nodes were assigned
to four different groups, and image review was conducted on a lymph-node group-by-group basis; 64 lymph-node groups were reviewed
by two radiologists. Relative sensitivity, specificity, and accuracy were determined based on the findings with definitive
surgery and follow-up imaging. Diagnostic accuracy was determined by means of receiver-operating-characteristic (ROC) analysis.
Results: Relative sensitivities for lymph-node metastases with T1-weighted SE, breath-hold T2-weighted fast SE, and dynamic GRE images
were 61%, 94%, and 59%, respectively. Relative sensitivity with breath-hold T2-weighted fast SE images was significantly greater
than that with T1-weighted SE (p < 0.05) and dynamic GRE (p < 0.05) images. Diagnostic accuracy determined by ROC analysis was marginally higher with breath-hold T2-weighted fast SE (area under
ROC curve [Az]= 0.87) than with T1-weighted SE (Az = 0.78, p= 0.08) and dynamic GRE (Az = 0.79, p= 0.12) images.
Conclusion: Breath-hold T2-weighted fast SE sequence is useful in the detection of regional lymph-node metastases in patients with gastric
carcinoma.
Received: 11 November 1998/Revision accepted: 7 April 1999 相似文献
15.
Intrahepatic splenosis: imaging features 总被引:1,自引:0,他引:1
De Vuysere S Van Steenbergen W Aerts R Van Hauwaert H Van Beckevoort D Van Hoe L 《Abdominal imaging》2000,25(2):187-189
We report a patient who presented with asymptomatic focal liver lesions and in whom a diagnosis of intrahepatic splenosis
was made. This rare condition mostly occurs in patients who previously underwent splenic trauma or surgery. Magnetic resonance
imaging (MRI) characteristics suggesting this diagnosis are described. The lesions were mainly hypointense on T1- and hyperintense
on T2-weighted images. After administration of small iron oxide particles (SPIO-Endorem), the lesions remained slightly hyperintense
relative to the hypointense liver parenchyma but showed a 50% loss in signal intensity. Knowledge of these MRI characteristics
may avoid the use of surgical interventions to arrive at the correct diagnosis of these rare liver lesions.
Received: 14 June 1999/Accepted: 14 July 1999 相似文献
16.
T. C. L. Soong R. C. Lee H. C. Cheng J. H. Chiang H. S. Tseng C. W. Lin M. M. H. Teng 《Abdominal imaging》1998,23(5):515-519
Background: To report the dynamic magnetic resonance (MR) imaging findings of hepatolithiasis.
Methods: Dynamic MR images (fast spoiled gradient echo sequence with intravenous injection of gadopentate dimeglumine) and computed
tomography, cholangiography, or angiography of nine patients with hepatolithiasis are analyzed.
Results: All affected hepatic segments showed atrophic changes and contained dilated intrahepatic ducts. These segments showed either
iso- or hypointensity on T1-weighted imaging and hyperintensity on T2-weighted imaging. Preferential enhancement was noted
throughout all phases of the dynamic study and persisted to delayed T1-weighted imaging in seven patients. In the last two
patients, severe atrophic changes made evaluating signal intensity differences and enhancement patterns difficult.
Conclusion: In addition to intrahepatic stones and biliary dilatation, segmental atrophy, signal intensity differences, and preferential
and persistent enhancement are important MR findings of hepatolithiasis.
Received: 18 June 1997/Accepted: 23 July 1997 相似文献
17.
Dysplastic nodules of the liver: imaging findings 总被引:2,自引:0,他引:2
Background: To verify characteristic features of hepatic dysplastic nodules at different imaging modalities.
Methods: Twenty-eight patients with 37 dysplastic nodules of the liver (0.8–3.0 cm) underwent sonography (28 patients), computed tomography
(CT; 24 patients), magnetic resonance (MR; 11 patients), and angiography (12 patients). Each nodule was analyzed for echogenicity,
attenuation, signal intensity, and vascularity.
Results: Echogenicity of nodules was high in 16 (43%), homogeneous in two (6%), and low in 19 (51%) of 37 nodules. Attenuation of
nodules was high in one (7%), homogeneous in four (26%), and low in 10 (67%) of 15 nodules on the arterial-phase CT images;
homogeneous in five (33%) and low in 10 (67%) of 15 nodules on the portal-phase CT images; and high in four (17%), homogeneous
in six (26%), and low in 13 (57%) of 23 nodules on the delayed-phase CT images. Signal intensity of nodules was high in 15
(94%) and homogeneous in one (6%) of 16 nodules on T1-weighted MR images and was homogeneous in seven (44%) and low in nine
(56%) of 16 nodules on T2-weighted MR images. Vascularity of nodules was avascular in 14 (88%) and slightly vascular in two
(12%) of 16 nodules.
Conclusions: Hepatic dysplastic nodules show diverse imaging characteristics with different imaging techniques; however, common imaging
findings of hepatic dysplastic nodules are low echo, low attenuation, and high, low, or homogeneous intensity on T1- and T2-weighted
MR, and avascularity.
Received: 13 May 1998/Accepted: 1 July 1998 相似文献
18.
MR imaging of intrahepatic cholangiocarcinoma 总被引:10,自引:0,他引:10
Background:
The purpose of this study was to determine the magnetic resonance (MR) features of intrahepatic cholangiocarcinoma.
Methods:
MR imaging studies of seven cases of pathologically proven intrahepatic cholangiocarcinoma were retrospectively reviewed.
Results:
On MR images the tumors presented as a single mass (N = 5) or multiple nodules (N = 2), as welldelineated (N = 5) or ill-defined (N = 2), and as non-encapsulated (N = 7). Mean tumor diameter ranged from 6–14 cm (mean, 10 cm). On T1-weighted (TR/TE = 400–600/10–17 msec) images, the tumors were hypointense compared to the liver. The five tumors studied with dynamic MR imaging showed progressive centripetal filling-in after intravenous administration of a gadolinium chelate. On T2-weighted (TR/TE = 2000–2500/80–100 msec) images, all tumors were hyperintense compared to the liver; five were markedly hyperintense and two moderately hyperintense. Vascular encasement, bile duct dilatation within the tumor, and central scar were depicted on MR images in four, three, and two tumors respectively.
Conclusion:
The typical MR appearance of intrahepatic cholangiocarcinoma is a large well-delineated nonencapsulated tumor associated with intrahepatic venous encasement. 相似文献
19.
Background: We compared T2-weighted and heavily T2-weighted breath-hold turbo spin-echo (TSE) sequences with T2-weighted non-breath-hold
TSE sequence to evaluate hepatic hemangiomas on magnetic resonance (MR) with a phased-array multicoil.
Methods: Twenty-two patients with 27 hemangiomas were studied at 1.0-T scanner by using T2-weighted and heavily T2-weighted breath-hold
TSE sequences (18 s each) and non-breath-hold T2-weighted TSE sequences with use of a phased-array multicoil. Images were
quantitatively analyzed for tumor-to-liver signal-difference-to-noise ratios (SD/Ns) and tumor-to-liver signal intensity ratios
(T/Ls) and qualitatively analyzed for tumor conspicuity and motion-induced image artifacts.
Results: Quantitatively, T2-weighted breath-hold TSE images showed the highest SD/Ns among the three sequences, although the differences
from the heavily T2-weighted breath-hold TSE sequence and the T2-weighted non-breath-hold TSE sequence were not statistically
significant (p= 0.61 and 0.06, respectively). Heavily T2-weighted breath-hold TSE images showed the highest T/Ls among the three sequences.
The differences from the T2-weighted breath-hold TSE sequence and the T2-weighted non-breath-hold TSE sequence were statistically
significant (p < 0.001). Qualitatively, breath-hold TSE images were superior to non-breath-hold TSE images in terms of tumor conspicuity
(p < 0.01) and motion artifacts (p < 0.01).
Conclusion: T2-weighted breath-hold TSE sequence is superior to T2-weighted non-breath-hold TSE sequence in the evaluation of hepatic
hemangiomas on MR with a phased-array multicoil.
Received: 7 April 1997/Accepted: 28 May 1997 相似文献
20.
Fascioliasis: US, CT, and MRI findings with new observations 总被引:2,自引:0,他引:2
Kabaalioğlu A Cubuk M Senol U Cevikol C Karaali K Apaydin A Sindel T Lüleci E 《Abdominal imaging》2000,25(4):400-404
Background: The purpose of this study is to describe the ultrasonographic (US), computed tomographic (CT), and magnetic resonance imaging
(MRI) findings in fascioliasis and to emphasize the impact of radiology in diagnosis.
Methods: Radiologic findings in 23 consecutive patients with fascioliasis were prospectively recorded. All patients had at least one
US and CT examination, and 10 of them were studied by MRI. All diagnoses were confirmed by serologic methods. In the first
three cases, initial diagnosis was reached by microscopic demonstration of the parasites' eggs in bile obtained by US-guided
gallbladder aspiration.
Results: In the hepatic phase of fascioliasis, multiple, confluent, linear, tractlike, hypodense, nonenhancing hepatic lesions were
detected by CT. On US, the parasites could be clearly identified in the gallbladder or common bile duct as floating and nonshadowing
echogenic particles. MRI showed the lesions as hypo- or isointense on T1-weighted images and as hyperintense on T2-weighted
images.
Conclusions: CT findings in the hepatic phase and US findings in the biliary phase are characteristic of fascioliasis. Because clinical
and laboratory findings of fascioliasis may easily be confused with several diseases, radiologists should be familiar with
the specific radiologic findings of the disease to shorten the usual long-lasting diagnostic process.
Received: 15 December 1999/Accepted: 26 January 2000 相似文献