[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE. This systematic review presents evidence-based consensus statements as reported by a multidisciplinary expert panel (six abdominal radiologists, four hepatobiliary surgeons, and two hepatologists) regarding the use of gadoxetic acid for liver MRI. CONCULSION. Although this review highlights the incremental diagnostic value of hepatobiliary phase imaging with gadoxetic acid-enhanced liver MRI in multiple clinical scenarios, there remains a need for further impact studies for some clinical applications, such as hepatocellular carcinoma in cirrhosis.
AJR. American journal of roentgenology. 04/2015; 204(204):498-509.
[Show abstract][Hide abstract] ABSTRACT: Cholangiocarcinomas are the second most common primary hepatobiliary tumors after hepatocellular carcinomas. They can be categorized either based on their location (intrahepatic/perihilar/extrahepatic distal) or their growth characteristics (mass-forming/periductal-infiltrating/intraductal) because they exhibit varied presentations and outcomes based on their location and or pattern of growth. The increased risk of cholangiocarcinoma in PSC necessitates close surveillance of these patients by means of imaging and laboratory measures; and because currently surgical resection is the only effective treatment for cholangiocarcinoma, the need for accurate pre-operative staging and assessment of resectability has emphasized the role of high quality imaging in management. Today magnetic resonance imaging (MRI) is the modality of choice for detection, pre-operative staging and surveillance of cholangiocarcinoma. J. Magn. Reson. Imaging 2014.
Journal of Magnetic Resonance Imaging 12/2014; · 2.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE. Inflammatory hepatocellular adenoma (HCA) is a recently categorized entity of hepatocellular neoplasms. We investigated whether gadoxetic acid-enhanced MRI can distinguish inflammatory HCA from focal nodular hyperplasia (FNH). MATERIALS AND METHODS. From January 1, 2009, through January 1, 2013, gadoxetic acid-enhanced MRI examinations from two institutions were reviewed for HCA, with specific histologic features of inflammatory HCA. Biopsy and resection slides were reviewed, and immunohistochemistry for glutamine synthetase was performed in a subset to confirm the initial diagnosis. RESULTS. A total of 10 possible cases of inflammatory HCA were identified in the pathology database. On the basis of glutamine synthetase staining performed for this study, three cases were rediagnosed as FNH and thus were excluded from the study. Therefore, a total of seven patients with inflammatory HCA were identified. On gadoxetic acid-enhanced MRI, four of these patients had classic features of FNH (group A, FNH mimics), and three had imaging features suggestive of HCA (group B, typical inflammatory HCA). Imaging features that were considered diagnostic of FNH included isointense or minimal T2 hyperintensity, arterial enhancement, and diffuse hyperintensity on hepatobiliary phase. Three of the four patients with FNH mimics had slides available for pathologic rereview, and the diagnosis of inflammatory HCA was supported by glutamine synthetase immunohistochemistry findings. The pathology reports of the remaining four cases were rereviewed and were also found to have features consistent with inflammatory HCA. CONCLUSION. Inflammatory HCA can mimic FNH on MRI, including hepatobiliary phase hyperintensity. Moreover, conventional pathology using histopathology alone may lead to misclassification of inflammatory HCA.
American Journal of Roentgenology 07/2014; · 2.74 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: MR imaging plays a key role in staging evaluation of rectal cancer. The cornerstone of staging MR involves high-resolution T2 imaging orthogonal to the rectal lumen. The goals of MR staging are identification of patients who will benefit from neoadjuvant therapy prior to surgery to minimize postoperative recurrence and planning of optimal surgical approach. MR provides excellent anatomic visualization of the rectum and mesorectal fascia, allowing for accurate prediction of circumferential resection margin status and tumor stage. MR has an evolving role for the evaluation of neoadjuvant treatment response, further triaging optimal patient treatment and surgical approach.
Magnetic resonance imaging clinics of North America 05/2014; 22(2):165-190.
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE. The purpose of this study was to perform a retrospective MRI-based comparative analysis of the morphologic patterns of bile duct disease in IgG4-related systemic disease (ISD, also called autoimmune pancreatitis) compared with primary sclerosing cholangitis (PSC) and the autoimmune liver diseases autoimmune hepatitis and primary biliary cirrhosis. MATERIALS AND METHODS. This study included 162 consecutively registered patients (47 with ISD, 73 with PSC, and 42 with autoimmune liver diseases). Two abdominal radiologists retrospectively reviewed MR images in consensus. Imaging findings on the bile ducts, liver, pancreas, and other organs were analyzed to establish disease patterns. RESULTS. ISD was associated with contiguous thickening of intrahepatic and extrahepatic bile ducts (p < 0.001), pancreatic parenchymal abnormalities (p < 0.001), renal abnormalities (p < 0.001), and gallbladder wall thickening (p < 0.03). The severity of common bile duct wall thickness was significantly different in ISD (p < 0.001). The mean single wall thickness in the ISD group was 3.00 (SD, 1.47) mm, in the PSC group was 1.89 (SD, 0.73) mm, and in the autoimmune liver disease group was 1.80 (SD, 0.67) mm. PSC was associated with liver parenchymal abnormalities (p < 0.001). We did not find statistical significance between the three groups in location (p = 0.220) or length (p = 0.703) of extrahepatic bile duct strictures, enhancement of bile duct stricture (p = 0.033), upper abdominal lymphadenopathy, or retroperitoneal fibrosis. Although presence of intrahepatic bile duct stricture was statistically significant when all three groups were compared, it was not useful for differentiating ISD from PSC. CONCLUSION. The presence of continuous as opposed to skip disease in the bile ducts, gallbladder involvement, and single-wall common bile duct thickness greater than 2.5 mm supports a diagnosis of ISD over PSC. ISD and PSC could not be differentiated on the basis of location and length of common bile duct stricture.
American Journal of Roentgenology 03/2014; 202(3):536-43. · 2.74 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE. The purpose of this study is to evaluate the interval growth, tumor recurrence, and metastatic disease occurrence of cystic renal cell carcinoma (RCC). MATERIALS AND METHODS. Pre-and posttreatment imaging of 47 histologically proven cystic RCCs, with at least 6 months of pretreatment imaging monitoring or at least 2 years of posttreatment imaging follow-up, or both, was retrospectively reviewed. Tumor morphologic features, preoperative growth, histologic typing and grading, and the incidence of tumor recurrence or metastasis were evaluated. Growth rate of tumors were compared among various histologic subtypes and Fuhrman grades. RESULTS. Of 47 tumors, 27 (57.5%) were clear cell RCCs, 12 (25.5%) were multilocular RCCs, and eight (17%) were papillary cystic RCCs. Overall, 26 (55.3%) tumors were graded as Fuhrman grade 2, 17 (36.1%) were Fuhrman grade 1, and one tumor was Fuhrman grade 3. Of the 26 tumors with a minimum of 6 months of pretreatment imaging monitoring, 19 (73%) did not show a significant increase in tumor size. The differences in mean growth among the Fuhrman grades and different subtypes were not statistically significant. The average duration of posttreatment follow-up was 51 months. There were no local recurrences among the 43 patients who underwent posttreatment imaging, except for one patient who had metastasis at preoperative clinical presentation. CONCLUSION. Cystic RCCs exhibit slow indolent growth, if any, and show no significant metastatic or recurrence potential, with excellent clinical outcomes. We raise the need for revisiting current imaging protocols that may involve frequent pre-and posttreatment imaging in cystic RCCs.
American Journal of Roentgenology 08/2013; 201(2):W292-6. · 2.74 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This article presents a radiologic perspective of male infertility. Basic embryologic, anatomic, and physiologic concepts underpinning male reproduction are explained. Common and uncommon abnormalities related to male infertility and subfertility are described, with emphasis on imaging findings and management strategies.
Radiologic Clinics of North America 11/2012; 50(6):1183-200. · 1.83 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Detection of muscle invasion is a critical aspect in management of urinary bladder cancer. MR imaging has the potential and promise of delivering this premise noninvasively. This article reviews the current status of MR imaging in evaluation of bladder cancer. Also discussed are other important neoplastic and nonneoplastic conditions affecting the bladder.
Radiologic Clinics of North America 11/2012; 50(6):1085-110. · 1.83 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Portal biliopathy refers to biliary abnormalities secondary to extrahepatic portal vein obstruction and cavernous transformation and is caused by vascular compression from peribiliary collateral vessels, producing segmental stenoses of the common bile duct and abnormal liver function test (LFT) results. A review of imaging studies yielded 18 patients with abnormal LFT results, biliary tract dilatation, and extrahepatic portal vein obstruction with cavernous transformation. Multidetector computed tomography and magnetic resonance imaging showed biliary stenotic segments in 11 patients secondary to extrinsic compression from enlarged peribiliary collaterals. Clinical and imaging follow-up demonstrated improvement in LFT results with minimal decrease in bile duct dilatation, eliminating percutaneous or endoscopic biliary intervention.
[Show abstract][Hide abstract] ABSTRACT: The management of renal cell carcinoma (RCC) is evolving owing to the increasing detection of small renal masses, greater understanding of the metabolic pathways involved, new targeted medical treatments for metastatic RCC, and evolving surgical and minimally invasive image-guided treatment techniques. Consequently, the role of imaging and radiology has expanded, with new challenges encompassing all aspects of management, including diagnosis, predicting cell type, staging, preoperative vascular mapping, image-guided treatment and biopsy, detection of recurrence and the use of imaging as a biomarker to assess response to treatment. This article is a comprehensive review of RCC, outlining the etiology of the disease, RCC histological subtypes and their imaging characteristics, imaging modality techniques for evaluation of RCC, treatment strategies and the management of small renal masses.
[Show abstract][Hide abstract] ABSTRACT: Pancreatic adenocarcinoma is the fourth leading cause of cancer death.
A prospective cohort study was undertaken between 2003 and 2011 at a tertiary care centre in Toronto, Canada. Two hundred and sixty-two subjects were enrolled based on an elevated estimated lifetime risk for pancreatic cancer due to known genetic mutations and/or cancer family history. Subjects underwent annual magnetic resonance imaging, followed by additional investigations if abnormal findings were detected. Evidence of malignancy or suspicious macroscopic abnormalities prompted referral for surgical intervention.
Average length of follow-up was 4.2 years, during which 84/262 (32%) subjects demonstrated pancreatic abnormalities. Three participants developed pancreatic adenocarcinoma (one 1.5-cm tumor was resected but recurred, while the other two subjects developed metastatic cancer), and a fourth participant developed a pancreatic neuroendocrine tumor that was resected. Fifteen subjects had radiologic evidence of branch-duct intraductal papillary mucinous neoplasms, of which two underwent surgical resection. Sixty-five subjects had simple pancreatic cysts that have remained stable.
Magnetic resonance imaging can detect small pancreatic tumors and cystic lesions, but further improvement in sensitivity is needed. An understanding of the natural history of pre-invasive lesions in members of high-risk families is necessary for developing a more effective screening program.
Journal of Gastrointestinal Surgery 11/2011; 16(4):771-83. · 2.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: American Association for the Study of Liver Diseases (AASLD) guidance recommends measurement of IgG4 in patients with sclerosing cholangitis (SC). The objective of this study was to evaluate this by analyzing our SC practice.
Characteristics were collected on 168 patients with radiological or biopsy proven SC; IgG4 was measured and magnetic resonance cholangiopancreatography studies were reviewed.
In all, 49% of patients were females and 55% had inflammatory bowel disease. Large duct disease was present in 63%, small duct disease in 8%, overlap with AIH in 11%, and secondary SC in 18%. Secondary etiologies included autoimmune pancreatitis (AIP) (8%), intra-hepatic cholelithiasis (3%), portal vein thrombosis (2%), and neonatal Kasai (2%). In all, 101 patients had sufficient radiology and serology for re-evaluation. IgG4 was elevated (>104 mg/dl) in 22% of patients. This was associated with male gender (73%; P=0.016), a past history of pancreatitis (27% vs. 5%; P=0.007), a higher alkaline phosphatase (ALP) value, median 338.5 U/l vs. 160 (P=0.005), and a higher primary sclerosing cholangitis (PSC) Mayo risk score, mean 0.6 vs. -0.2 (P=0.0008). Prior biliary intervention was more likely (36 vs. 13%; P=0.023), while abnormal pancreatic imaging was noted in 15%, more frequently if IgG4 was elevated (40 vs. 8%; P=0.0007). After excluding those with pancreatic disease on magnetic resonance imaging, 14 patients had elevated IgG4. This group had higher ALP 379 U/l vs. 155.5 (P=0.0006), aspartate aminotransferase (AST) 72.5 U/l vs. 34 (P=0.0005), alanine aminotransferase (ALT) 90.5 U/l vs. 36 (P=0.004), and PSC Mayo risk score values 0.4 vs. -0.2 (P=0.017).
SC is a heterogeneous liver injury. IgG4 testing may be clinically important in all patients, since it appears to identify a distinct patient population, more so than just those with AIP.
The American Journal of Gastroenterology 11/2011; 107(1):56-63. · 9.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of our study was to evaluate the association of hepatic hemangiomatosis with giant cavernous hemangioma (GCH) and describe the imaging appearances and clinical relevance.
Forty-one patients who had undergone CT or MRI with reported GCH (> 8 cm) between 1997 and 2009 were identified retrospectively. Three readers interpreted 27 MRI studies, 36 CT studies, and 16 ultrasound studies of these patients. Prevalence, extent, and imaging appearance of coexistent hemangiomatosis in the surrounding liver parenchyma were evaluated.
Forty-two GCHs were identified in 41 patients and hemangiomatosis was present in 18 of 41 patients (44%) with GCH. Twelve patients had a diffuse pattern of hemangiomatosis (67%), and six patients showed a nodular pattern consisting of multiple coalescent nodules measuring < 5 mm (33%). There was no association between the size of the GCH and presence and extent of hemangiomatosis. The common hepatic artery was enlarged (> 5 mm) in 14 patients with GCH, of whom 12 had associated hemangiomatosis. There was a statistically significant association between the size of the hepatic artery and presence of hemangiomatosis (p < 0.001).
Hemangiomatosis is not rare in the liver parenchyma adjacent to a GCH. The presence and extent of hemangiomatosis must be specifically communicated to referring physicians. Surgical candidates have to be carefully selected to avoid complications, such as excessive blood loss and diminished risk of postoperative liver decompensation from apparent overestimation of functional residual volume due to oversight of involved liver areas by hemangiomatosis.
American Journal of Roentgenology 04/2011; 196(4):809-15. · 2.74 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to assess the potential role for chemical shift magnetic resonance imaging (MRI) in identifying lymphangiomas from other cystic mesenteric and retroperitoneal masses.
A retrospective search of radiology database identified 24 consecutive patients with mesenteric and retroperitoneal cysts (nine men, 15 women; mean age, 41 years; age range, 19-75 years) who had undergone MR which included in-phase and opposed-phase chemical shift imaging. Signal intensity (SI) decrease between in-phase and opposed-phase MR images of the cyst was evaluated qualitatively by two radiologists. Ultrasound (US), computed tomography (CT), and MRI findings of the morphological appearances of all the cystic lesions that demonstrated significant signal drop on chemical shift MR were also recorded.
Of mesenteric and retroperitoneal cysts, 33% (8/24) revealed qualitative decrease in intensity on opposed-phase MR images relative to that seen on in-phase images. On ultrasound, these cysts demonstrated anechoic simple fluid. Their mean CT attenuation was 13 HU (range: 5-20 HU). Signal loss on fat-suppressed T1-weighted sequences was displayed only by a single cyst. None of the lesions with qualitative SI decrease on opposed-phase MR showed suggestion of lipid on US and CT.
The presence of intra cystic lipid detected by chemical shift MR may not be overt on cross-sectional imaging such as US and CT. Chemical shift MRI provides additional sensitivity and specificity as an imaging test for demonstration of lipid within mesenteric and retroperitoneal cysts enabling a higher diagnostic yield for lymphangioma leading to more appropriate patient management.