BACKGROUND: Double contrast magnetic resonance (MR) imaging using superparamagnetic iron oxide (SPIO) and gadolinium (Gd) is performed to detect and characterize focal liver lesions. However, this technique is a costly and lengthy process. The purpose of this study was to determine the usefulness of SPIO-enhanced MR imaging including SPIO-enhanced T1-weighted imaging in diagnosing focal liver lesions. METHODS: Eighty-four focal liver lesions were examined with a 1.5-T MR unit. Transverse precontrast T1- and T2-weighted images and SPIO (ferumoxides)-enhanced T1- and T2-weighted images were obtained, followed by Gd-enhanced T1 -weighted imaging. The Gd set (i.e., precontrast T1- and T2-weighted and delayed-phase gadolinium-enhanced T1-weighted images) and ferumoxides set (i.e., precontrast T1- and ferumoxides-enhanced T1- and T2-weighted images) were reviewed by two independent readers. RESULTS: More lesions were detected from the ferumoxides set than from the Gd set. Ferumoxides-enhanced T1-weighted imaging showed enhancement patterns of the lesions similar to those of delayed-phase Gd-enhanced T1-weighted imaging. The diagnoses of hepatic metastasis and cyst by the ferumoxides set were similar to those by the Gd set. However, a dynamic study may be inevitable for the diagnosis of hepatocellular carcinoma and hemangioma. CONCLUSION: The ferumoxides set was useful for the detection of focal hepatic lesions. Ferumoxides-enhanced T1-weighted imaging may replace delayed-phase gadolinium-enhanced T1-weighted imaging in the diagnosis of hepatic metastasis and cysts.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

Nonenhanced magnetic resonance imaging of mild acute pancreatitis.

BACKGROUND: Computed tomography (CT) is not always effective for demonstrating mild acute pancreatitis, and the intravenous administration of iodine contrast medium is harmful to the inflamed pancreas. The goal of this study was to evaluate the usefulness of nonenhanced magnetic resonance (MR) imaging for the depiction of mild acute pancreatitis. METHODS: We performed T1-weighted imaging with a short echo time, T2-weighted imaging, and MR cholangiopancreatography (MRCP) in 12 patients with mild acute pancreatitis. Nonenhanced CT and contrast-enhanced CT were always performed before the MR studies. RESULTS: T1- and T2-weighted MR images using a breath-hold or respiratory-triggered technique produced clearer images of the inflamed pancreas than did CT. Peripancreatic fat necrosis was shown by both methods. Although MRCP demonstrated no abnormalities of the pancreatic duct, it demonstrated stones in the gallbladder and common bile duct. CONCLUSIONS: Nonenhanced MR imaging was superior to CT for depiction and confirmation of mild acute pancreatitis.

Acute Disease↗

PubMedDate not supplied

MR appearances of urinary bladder in amyloidosis associated with multiple myeloma.

Amyloidosis led to thickening of the urinary bladder wall, with hypointensity in T2-weighted images, which was distinguished from multiple myeloma involvement.

Amyloidosis↗

PubMedDate not supplied

Fat-suppressed gadolinium-enhanced three-dimensional magnetic resonance angiography adequately depicts the status of iliac arteries following atherectomy and stent placement.

Fat-suppressed, three-dimensional magnetic resonance angiography (3D MRA) was performed on nine patients with 11 iliac artery stenoses following atherectomy or stent placement. The MRA accurately depicted continued patency, restenosis, or aneurysm formation when compared with immediate posttreatment conventional arteriography. Therefore MRA is accurate and can be used independently for clinical decision making.

Aged↗

PubMedDate not supplied

Case report: serous atrophy of bone marrow and subcutaneous tissue enhancement associated with recurrent rectal carcinoma: MR appearances.

We report a case of serous atrophy of bone marrow associated with recurrent rectal carcinoma detected by MR images. Bone marrow of vault, clivus and femur showed waterlike signal patterns in T1- and T2-weighted images. Postcontrast T1-weighted images revealed no enhancement of bone marrow, while subcutaneous tissue showed decreased signal intensity and enhancement consistent with an increase in connective tissue with fat atrophy. Gadolinium-enhanced MR imaging was useful for differentiating the serous atrophy of marrow from bone metastasis in this carcinoma patient.

Aged↗

PubMedDate not supplied

Intraluminal signal intensity of iliac artery stents investigated by contrast-enhanced three-dimensional MR angiography.

The purpose of this study is to investigate the intraluminal signal of iliac artery stents by contrast-enhanced three-dimensional magnetic resonance (MR) angiography with a short echo time. Ten patients with iliac arterial diseases treated by intravascular metallic stent placement were examined with a 1.5 T MR imager. Gadolinium-enhanced MR angiography depicted the intraluminal signal in Strecker stent, but not in the Wallstent and Palmaz stent. Strecker stent made of nonferromagnetic tantalum was the best-suited stent for use with contrast-enhanced MR angiography.

Aged↗

PubMedDate not supplied

Peak blood flow measurement of coronary sinus by cine phase contrast MR imagings: comparison between breath-hold and respiratory compensation techniques.

The aim of this study was to assess the feasibility of cine phase contrast (PC) magnetic resonance (MR) imaging for the peak blood flow measurement of the coronary sinus. Conventional PC imaging demonstrated the coronary sinus clearly and the significantly higher peak flow compared with the corresponding values measured with breath-hold fast cine PC imaging techniques at end-inspiration and end-expiration. This study showed the feasibility of conventional cine PC imaging with respiratory compensation in measurement of coronary sinus blood flow.

Adult↗

PubMedDate not supplied

Magnetic resonance imaging of myelofibrosis. STIR and gadolinium-enhanced MR images.

MR images of myelofibrosis were assessed in twelve patients. Myelofibrosis showed low intensity in T1-weighted images, high intensity in STIR images, and enhancement after gadolinium injection. MR spectroscopy detected a large water resonance. MR imaging was consistent with histological findings and useful in evaluating the extracellular space in bone marrow of myelofibrosis, but it was of no value in differentiating between primary and secondary myelofibrosis.

Bone Marrow↗

PubMedDate not supplied

Metallic artifacts of coronary and iliac arteries stents in MR angiography and contrast-enhanced CT.

Metallic artifacts of intravascular stents were assessed with MR angiography and contrast-enhanced spiral CT. Stainless steel showed less metal artifact than tantalum stent in CT. Metallic artifact in coronary and iliac arteries treated with tantalum stent was not remarkable in MR angiography. Contrast-enhanced CT might be preferable to assess patency of arteries treated with stainless steel stent. while MR angiography was useful in depicting intraluminal signal in tantalum stent.

Aged↗