1,720,965 research outputs found
Mezzi di contrasto
Full text linkLa RM offre l’opportunità di esplorare l’organismo umano nella sua componente normale e patologica non solo dal punto di vista morfologico, ma anche da quello funzionale, grazie allo sviluppo di mdc sempre più sofisticati. Il loro utilizzo, tuttavia, rende necessaria una profonda conoscenza dei meccanismi d’azione del mdc e dell’interazione tra mdc e processi patologici, al fine di ottenere il maggior numero di informazioni possibili
Early B cell developmental impairment with progressive B cell deficiency in NFKB2 mutated CVID disease without autoimmunity.
Full text linkThis study provides evidence for a novel role for NFKB2 in human B cell development in the bone marrow and in
the periphery, leading to progressive peripheral B cell deficiency not always combined with autoimmune phenomena,
broadening thus the clinical spectrum of NFKB2 mutated CVID disease and implying an essential role
for NFKB2 in early human B cell development
MR imaging of focal nodular hyperplasia (FNH) with gadobenate dimeglumine (Gd-BOPTA) and SPIO (Ferumoxides): an intra-individual comparison
No full textPURPOSE: To compare the efficacy of two different MR contrast agents for the
detection and diagnosis of focal nodular hyperplasia (FNH).
MATERIALS AND METHODS: Fifty patients with 83 FNH lesions detected on spiral CT
were studied in two different MRI sessions with Gd-BOPTA (MultiHance) and
ferumoxides (Endorem). MRI with Gd-BOPTA was performed precontrast (T1wGRE and
T2wTSE sequences) and during the dynamic and late (1-3 hours) phases after
injection (T1wGRE sequences only). MRI with ferumoxides (T1wGRE and T2wTSE
sequences) was performed before and at least 30 minutes after injection. Hyper-
or isointensity of FNH in the late phase was considered typical for Gd-BOPTA,
while isointensity or lesion hypointensity was considered typical for
ferumoxides.
RESULTS: With Gd-BOPTA, 83 FNH lesions (100%) appeared hyperintense during the
arterial phase of dynamic MRI. All but one lesion was iso- or slightly
hyperintense in the portal-venous and equilibrium phases. In the late phase, 81
FNH lesions were hyper- or isointense to the surrounding parenchyma, with two
lesions appearing slightly hypointense. With ferumoxides, a significant (P <
0.001) number (21/83, 25.3%) of FNH lesions (mean diameter = 16.8 +/- 6.6 mm)
were not visible. Of the visible FNH lesions, 38/62 were slightly hyperintense,
and 24/62 were isointense to the surrounding parenchyma on the T2wTSE images. On
the T1wGRE images, 42/62 lesions were isointense, 19/62 were slightly
hyperintense, and one lesion was slightly hypointense. Seventeen lesions in 12
patients with previous neoplasia were all detected after Gd-BOPTA administration,
whereas only nine of these 17 lesions (52.9%) were detected after ferumoxide
administration. Two of these nine lesions showed atypical enhancement features.
CONCLUSION: Gd-BOPTA-enhanced MRI is significantly better than
ferumoxide-enhanced MRI for the identification and characterization of FNH
HRCT finding of primary immunodeficiencies: analysis of pulmonary changes in patients with hypogammaglobulinaemia
No full textSolid hypervascular liver lesions: accurate identification of true benign lesions on enhanced dynamic and hepatobiliary phase magnetic resonance imaging after gadobenate dimeglumine administration.
No full textPURPOSE:To evaluate hepatobiliary phase magnetic resonance imaging with gadobenate dimeglumine for differentiation of benign hypervascular liver lesions from malignant or high-risk lesions.METHODS AND MATERIALS:Retrospective assessment was performed of 550 patients with 910 hypervascular lesions (302 focal nodular hyperplasia [FNH], 82 nodular regenerative hyperplasia [NRH], 59 hepatic adenoma or liver adenomatosis [HA/LA], 329 hepatocellular carcinomas [HCC], 12 fibrolamellar-HCC [FL-HCC], 21 peripheral cholangiocarcinomas [PCC], 105 metastases). Imaging was performed before and during the arterial, portal-venous, equilibrium, and hepatobiliary phases after gadobenate dimeglumine administration (0.05 mmol/kg). Histologic confirmation was available for ≥1 lesion per patient, except for patients with suspected FNH (diagnosis based on characteristic enhancement/follow-up). Lesion differentiation (benign/malignant) on the basis of contrast washout and lesion enhancement (hypo-/iso-/hyperintensity) was assessed (sensitivity, specificity, accuracy, PPV, and NPV) relative to histology or final diagnosis.RESULTS:On portal-venous or equilibrium phase images, washout was not seen for 208 of 526 (39.5%) malignant (HCC, FL-HCC, PCC, metastases) and high-risk (HA/LA) lesions. Conversely, only 5 of 384 (1.3%) true benign lesions (FNH/NRH) showed washout. Taking washout as indicating malignancy, the sensitivity, specificity, and accuracy for malignant lesion identification during these phases was 61.8%, 98.7%, and 77.4%. On hepatobiliary phase images, 289 of 302 FNH, 82 of 82 NRH, 1 of 59 HA or LA, 62 of 341 HCC or FL-HCC, and 2 of 105 metastases were hyperintense or isointense. Taking iso- or hyperintensity as an indication for lesion benignity, the sensitivity, specificity, accuracy, PPV, and NPV for benign lesion identification was 96.6%, 87.6%, 91.4%, 85.1%, and 97.3%, respectively.CONCLUSIONS:Hepatobiliary phase imaging with gadobenate dimeglumine is accurate for distinguishing benign lesions from malignant or high-risk lesions. Biopsy should be considered for hypointense lesions on hepatobiliary phase images after gadobenate dimeglumine
Solid focal liver lesions: dynamic and late enhancement patterns with the dual phase contrast agent gadobenate dimeglumine.
No full textINTRODUCTION: The purpose of this paper is to illustrate contrast enhancement patterns of solid focal liver lesions on dynamic and late phase imaging with gadobenate dimeglumine (Gd-BOPTA). IMAGING
FINDINGS: Unenhanced T2- and T1-weighted, dynamic T1-weighted (arterial, portal-venous, and equilibrium) and late phase (1-3 h) Gd-BOPTA-enhanced MR imaging of different focal liver lesions (nodular regenerative hyperplasia, hepatic adenoma, liver adenomatosis, hepatocellular carcinoma, peripheral cholangiocarcinoma, hypervascular metastases, and hypovascular metastases) are shown. Dynamic imaging was performed using GRE T1-w sequences after the bolus injection of 0.1 mmol/kg Gd-BOPTA; late-phase imaging was obtained at 1-3 h after contrast injection.
CONCLUSIONS: Dynamic imaging with Gd-BOPTA provides the same information as with conventional gadolinium-based extracellular contrast agents, while late-phase imaging gives additional information for lesion identification and characterization
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