R L Baron

University of Pittsburgh, Pittsburgh, PA, United States

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Publications (49)233.5 Total impact

  • R L Baron · M S Peterson
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    ABSTRACT: The inherent distortion of the appearance of liver parenchyma by the underlying pathologic changes of cirrhosis can obscure and simulate malignancy at imaging. That hepatocellular carcinoma is the most common abdominal malignancy worldwide and occurs most often in patients with chronic liver disease and cirrhosis compounds this problem. Magnetic resonance (MR) imaging and, to a lesser extent, computed tomography (CT) can depict the underlying nodular and fibrotic changes in patients with cirrhosis, particularly when siderotic nodular regeneration is present. Application of state-of-the-art helical CT and MR imaging techniques has improved the ability to detect hepatocellular carcinoma in this population, but, even with these advances, fewer than 50% of small tumors are detected with either of these techniques in a screening population. Dynamic hepatic arterial-phase contrast material-enhanced imaging is essential with both CT and MR imaging to achieve even these levels of success. Benign lesions that simulate tumor tissue are encountered in many patients with cirrhosis and include focal fibrosis, infarcted regenerative nodules, arteriovenous shunts, hemangiomas, pseudoaneurysms, and focal transient hepatic enhancement. An awareness of the imaging characteristics of these lesions can help one avoid a mistaken diagnosis of hepatocellular carcinoma in many cases.
    Radiographics 11/2001; 21 Spec No:S117-32. · 2.60 Impact Factor
  • T Kim · R L Baron · M A Nalesnik
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    ABSTRACT: 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.
    American Journal of Roentgenology 11/2000; 175(4):1121-5. · 2.73 Impact Factor
  • M S Peterson · R L Baron · S C Rankin
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    ABSTRACT: OBJECTIVE: The objective of our study was to identify multiphasic contrast-enhanced helical CT findings of angiosarcoma of the liver to determine whether this tumor could be confused with hemangioma of the liver. CONCLUSION: Angiosarcoma of the liver is a multifocal tumor with a variety of findings on multiphasic contrast-enhanced helical CT. None of the findings would usually be confused with the typical findings of hepatic hemangioma.
    American Journal of Roentgenology 08/2000; 175(1):165-70. · 2.73 Impact Factor
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    G D Dodd · R L Baron · J H Oliver · M P Federle
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    ABSTRACT: Cirrhosis, through the process of necrosis, fibrosis, regeneration, and malignant transformation, creates multiple focal benign and malignant hepatic masses. The detection and appearance of these masses varies with the severity of the cirrhotic process and the imaging technique used. Although some overlap exists in the imaging appearance of the benign and malignant masses, in most instances recognition of a few characteristic features will yield the correct diagnosis.
    American Journal of Roentgenology 12/1999; 173(5):1185-92. DOI:10.2214/ajr.173.5.10541086 · 2.73 Impact Factor
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    G D Dodd · R L Baron · J H Oliver · M P Federle
    American Journal of Roentgenology 11/1999; 173(4):1031-6. DOI:10.2214/ajr.173.4.10511173 · 2.73 Impact Factor
  • M S Peterson · T Murakami · R L Baron
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    ABSTRACT: To determine the spectrum of appearances of gadolinium retention within cholangiocarcinoma (CCA) and other liver neoplasms. Two hundred ten patients underwent hepatic magnetic resonance imaging (MRI) at 1.5 T with precontrast T1- and T2-weighted spin-echo (SE) images and delayed Gd-DTPA- or gadoteridol- (0.1 mmol/kg) enhanced T1-weighted SE images. Postcontrast images were evaluated for lesions suspicious for tumors, and lesion signal intensity was characterized as homogeneously or heterogeneously hypo-, iso-, mildly hyper-, or markedly hyperintense to liver. Data from 94 patients with benign or malignant neoplasms are presented. Imaging demonstrated 237 malignant neoplasms (121 hepatocellular carcinoma [HCC], 26 CCA, 17 colon carcinoma metastases, 73 other tumors) and 28 benign neoplasms (22 hemangioma, six focal nodular hyperplasia [FNH]). One hundred forty malignant lesions appeared as homogeneous postcontrast (29 hypointense, 75 isointense, 17 mildly hyperintense, 19 markedly hyperintense) and 97 as heterogeneous (15 isointense, 50 mildly hyperintense, 32 markedly hyperintense). Malignant lesions showing homogeneous, mildly or markedly hyperintense signal intensity postcontrast included 10 CCA, seven HCC, six epithelioid hemangioendothelioma, eight neuroendocrine tumor metastases, three adenocarcinoma metastases of unknown origin, and one breast carcinoma metastasis. Hemangiomas appeared as homogeneous postcontrast in 19 lesions (six isointense, one mildly hyperintense, 12 markedly hyperintense) and as heterogeneous in three lesions (markedly hyperintense). FNH appeared as homogeneous postcontrast in one lesion (isointense) and as heterogeneous in five lesions (one isointense, four mildly hyperintense). Homogeneous gadolinium retention on delayed postcontrast images of malignant hepatic neoplasms is seen in a high percentage of CCA lesions and less commonly with other neoplasms.
    Abdominal Imaging 11/1998; 23(6):592-9. DOI:10.1007/s002619900410 · 1.63 Impact Factor
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    ABSTRACT: To assess the value of computed tomography (CT), cholangiography, ultrasonography (US), and magnetic resonance (MR) imaging in the demonstration of biliary tract carcinoma complicating primary sclerosing cholangitis (PSC). Thirty patients were studied who had PSC and biliary tract carcinoma. Twenty-six patients had cholangiocarcinoma, and four had gallbladder carcinoma. Sixty-four CT scans, 41 cholangiograms, 40 US studies, and seven MR studies were reviewed retrospectively for evidence of tumor and PSC. Imaging results were correlated with pathologic findings from whole liver specimens and biopsies. Presence of mass was rated as definite, probable, possible, or doubtful or absent. On CT scans, cholangiocarcinomas produced hypoattenuating masses in 17 of 23 cases, delayed contrast enhancement in six of 12, progressive biliary dilatation in five of 15, and thickened bile duct wall in two of 23. On cholangiograms, dominant strictures were present in 18 of 21 cases of cholangiocarcinoma; 13 were malignant, and five were benign. Cholangiocarcinoma formed polypoid bile duct masses in two of 21 cases. Biliary dilatation was caused by cholangiocarcinoma in 10 of 12 cases and by benign stricture in two. Gallbladder carcinomas demonstrated masses on CT scans, cholangiograms, and US images, and wall thickening on CT and US images. Overall, definite or probable tumor was demonstrated in 25 of 30 patients (83%). Most biliary tract carcinomas complicating PSC can be demonstrated on imaging studies.
    Radiology 04/1998; 207(1):41-50. DOI:10.1148/radiology.207.1.9530297 · 6.87 Impact Factor
  • J H Oliver · R L Baron · M P Federle · B C Jones · R Sheng
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    ABSTRACT: To evaluate the relative roles of unenhanced and hepatic arterial phase (HAP) computed tomographic (CT) imaging in the detection of hypervascular liver metastases. Eighty-four patients with biopsy-proved liver metastases from hypervascular primary tumors other than hepatocellular carcinoma underwent unenhanced and HAP and portal venous phase (PVP) helical CT studies. Three blinded radiologists evaluated each series of images separately for the number, size, and enhancement characteristics of lesions. Sixty-nine patients had follow-up imaging proof of tumor burden. The three readers detected 381-402 lesions on the PVP images and 397-416 lesions on the unenhanced images. Unenhanced images allowed detection of 72%-80% of the lesions seen on PVP images. They detected 94-137 additional lesions on unenhanced but not PVP images. On the HAP images, 375-395 lesions were identified. HAP images allowed detection of 81%-90% of the lesions seen on PVP images. Forty-five to 78 additional lesions were detected on HAP but not on PVP images. In the 69-patient subset, maximal detection of tumor foci occurred in 94% of patients with unenhanced plus PVP images and in 78% with HAP plus PVP images. Unenhanced plus PVP images allowed detection of 96% of the 322 tumors in the subset population. Unenhanced plus PVP CT images allow detection of statistically significantly more hypervascular liver metastases than do HAP plus PVP images or imaging only in the PVP.
    Radiology 01/1998; 205(3):709-15. DOI:10.1148/radiology.205.3.9393525 · 6.87 Impact Factor
  • M Kanematsu · J H Oliver · B Carr · R L Baron
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    ABSTRACT: To assess the role of helical biphasic computed tomography (CT) versus CT during arterial portography (CTAP) in the detection of hepatocellular carcinoma (HCC). Helical biphasic CT and CTAP examinations were performed in 33 patients with biopsy-proved HCC. Three blinded radiologists retrospectively evaluated portal venous phase images, portal venous phase plus hepatic arterial phase images (helical biphasic CT), and CTAP plus portal venous phase images at separate sittings. In 23 patients with pathologic proof of total tumor burden, the readers conducted a consensus matched-pair reading to determine the sensitivity of each method. In the 23 patients with a proved tumor burden of 100 HCC lesions, the observers detected 74 tumors on portal venous phase images, 82 tumors on hepatic arterial phase images, 87 tumors on CTAP images, 87 tumors on helical biphasic CT images, and 96 tumors on portal venous phase plus CTAP images. Hepatic arterial phase images and CTAP images, respectively, depicted 13 and 23 tumors not seen on portal venous phase images in eight (35%) and 13 (56%) of 23 patients. Ten tumors were seen on portal venous phase images but not on CTAP images owing to the presence of central tumors or segmental portal venous thrombi that obstructed the flow of contrast material to more peripheral portions of the liver. The addition of hepatic arterial phase imaging to portal venous phase imaging (helical biphasic CT) provided an incrementally increased yield in HCC tumor detection. Helical biphasic CT should be used as the initial screening examination in patients with suspected or known HCC.
    Radiology 11/1997; 205(1):75-80. DOI:10.1148/radiology.205.1.9314965 · 6.87 Impact Factor
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    ABSTRACT: To determine the imaging appearance and frequency of detection of bile duct calculi in patients with primary sclerosing cholangitis. Images (169 computed tomographic [CT] scans, 155 sonograms, and 109 cholangiograms) of 189 patients with primary sclerosing cholangitis, five of whom were prospectively included, were reviewed. Pathologic records were reviewed for proof of the presence of calculi. Bile duct calculi were visualized on images in 14 (7.6%) of the 184 retrospective patients and in all five of the prospective patients. The presence of calculi was confirmed with pathologic or imaging findings in 19 patients, in whom calculi were visible on 16 of 18 CT scans, 15 of 19 sonograms, and 14 of 17 cholangiograms. Calculi were in the intrahepatic ducts in 11 patients and in the intra- and extrahepatic bile ducts in eight patients. At CT, calculi appeared as foci of faint high attenuation or as coarse calcifications in nondilated or variably dilated ducts. At sonography, they appeared as unique echogenic casts with variable posterior acoustic shadowing or as discrete, echogenic, variably shadowing foci in variably dilated ducts. Calculi were depicted at cholangiography as rounded filling defects. Intrahepatic bile duct calculi are present in approximately 8% of patients and can have a unique imaging appearance.
    Radiology 06/1997; 203(2):443-7. DOI:10.1148/radiology.203.2.9114102 · 6.87 Impact Factor
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    ABSTRACT: To determine the usefulness of delayed post-equilibrium-phase contrast material-enhanced images in evaluation of intrahepatic cholangiocarcinoma. Review of surgical, pathologic, and radiologic records revealed 47 patients with proved cholangiocarcinoma with delayed (6-36 minutes) post-equilibrium-phase contrast-enhanced computed tomographic (CT) scans. Unenhanced, dynamic contrast-enhanced, and delayed images were retrospectively reviewed, and enhancement patterns for cholangiocarcinoma lesions were recorded. Degree of delayed enhancement was compared with that of surrounding liver parenchyma. Patterns of delayed enhancement were characterized as homogeneous or heterogeneous. Enhancement characteristics were correlated with histologic findings. Thirty-five (74%) of 47 patients had tumors with mild or marked hyperattenuating delayed contrast enhancement, of which 18 had tumors with homogeneous hyperattenuating enhancement. In three patients, the only evidence of tumor was on the delayed images. In one patient, the tumor was not definable at any imaging phase. Tumors with delayed enhancement tended to be fibrous; however, degree of contrast material retention did not always correlate with the fibrous content of tumors at histopathologic analysis. Delayed tumoral contrast enhancement is a typical feature of intrahepatic cholangiocarcinoma and may aid in the detection and characterization of such lesions at CT.
    Radiology 05/1997; 203(1):98-104. DOI:10.1148/radiology.203.1.9122423 · 6.87 Impact Factor
  • B I Carr · A Zajko · K Bron · P Orons · J Sammon · R Baron
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    ABSTRACT: Patients with advanced-stage unresectable hepatocellular carcinoma (HCC) were treated with intrahepatic arterial doxorubicin 30 mg/m2 plus escalating doses of cisplatin up to 100 mg/m2 in conjunction with rapid bolus injection of Spherex (degradable starch microspheres; Kabi Pharmacia, Lund, Sweden) into the hepatic artery, until slowing or reversal of blood flow. Treatments were repeated every 4 to 6 weeks until progression, or were continued indefinitely if there was disease stability or response. Thirty-five evaluable patients have so far been accrued to the study. Objective tumor responses have occurred in 22 patients (63%), of whom 20 had partial responses and two had complete responses. Four of the patients had reversal of tumor-induced portal vein thrombus. Toxicities included death, one patient (and a death of uncertain cause in an additional patient); hepatitis, two patients; pancreatitis, one patient; dyspnea/hypotension, two patients; and hepatic artery nontransient thrombosis in four patients. Six patients have survived 2 years and an additional 10 patients have survived 1 year. The addition of Spherex to intrahepatic arterial chemotherapy for advanced-stage HCC appears to be relatively safe and is well tolerated even in patients with portal vein thrombosis, which represent the majority of patients with advanced-stage HCC.
    Seminars in Oncology 05/1997; 24(2 Suppl 6):S6-97-S6-99. · 3.90 Impact Factor
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    M E Tublin · G D Dodd · R L Baron
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    ABSTRACT: The purpose of this study was to determine if unique characteristics revealed by CT can allow radiologists to reliably distinguish benign from malignant portal vein thrombus (PVT) in patients with cirrhosis. CT examinations of 58 patients with cirrhosis and PVT were retrospectively reviewed. Images were assessed for location, extent, enhancement, neovascularity, and maximal diameter of PVT. The type of PVT was proven histologically in 42 patients and clinically in the remaining 16 patients. Using different threshold PVT diameters or the presence of PVT neovascularity, we calculated the sensitivity and specificity of CT for revealing malignant PVT. Forty-seven patients had malignant and 11 patients had benign PVT. CT scans of patients with malignant PVT showed direct extension of hepatocellular carcinoma into the portal vein in 15 patients. In 29 patients with malignant PVT, CT scans showed PVT adjacent to tumor; CT scans showed tumor PVT remote from hepatocellular carcinoma in the remaining three patients with malignant PVT. The mean diameters of malignant and benign portal vein thrombi were significantly different (23.4 mm versus 16 mm; p = .0001). CT scans of 83% (39/47) of patients with malignant PVT and 18% (2/11) of patients with benign PVT showed generalized enhancement. Neovascularity was seen on CT scans in 43% (20/47) of patients with malignant PVT and in no patient with benign PVT. Identification of a main PVT diameter greater than or equal to 23 mm or PVT neovascularity resulted in a sensitivity and specificity for the CT characterization of malignant PVT of 86% and 100%, respectively. Malignant and benign thrombi can often be differentiated by radiologists on the basis of CT imaging characteristics.
    American Journal of Roentgenology 04/1997; 168(3):719-23. DOI:10.2214/ajr.168.3.9057522 · 2.73 Impact Factor
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    ABSTRACT: To determine the frequency, distribution, size, and cause of enlarged abdominal lymph nodes in patients with end-stage cirrhosis. Preoperative computed tomographic (CT) scans from 507 hepatic transplantation patients with end-stage cirrhosis were reviewed for the presence, size, and location of enlarged (short-axis diameter > 1 cm) abdominal lymph nodes. Enlarged lymph nodes were identified and resected at surgery. Resected livers were evaluated for malignant neoplasms. CT findings were correlated with histopathologic results. Enlarged abdominal lymph nodes were detected with CT in 253 (50%) of the patients. The enlarged nodes were 1.1 x 1.1 to 3.0 x 4.5 cm in size and were most common in the portacaval space and porta hepatis. The frequency of enlarged nodes varied according to type of cirrhosis: They were most common in patients with primary biliary cirrhosis (86% [43 of 50]) and least common in patients with alcohol-induced cirrhosis (37% [42 of 113]). Histologic evaluation revealed that the enlarged lymph nodes were due to benign nodal hyperplasia in 251 patients and malignant neoplasm in two patients. Enlarged abdominal lymph nodes are common in patients with all forms of end-stage cirrhosis. In the absence of other evidence of malignancy, enlarged nodes in these patients should be considered a benign process, with no additional evaluation warranted.
    Radiology 04/1997; 203(1):127-30. DOI:10.1148/radiology.203.1.9122379 · 6.87 Impact Factor
  • R L Baron · J H Oliver
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    ABSTRACT: The dual blood supply to the liver, that of hepatic arterial supply and portal venous blood supply represents both opportunity and trouble for radiologists in using contrast material to detect liver neoplasms. It is this unique feature that allows one to optimize tumor detection by optimizing contrast flow to either the liver parenchyma or to tumors. Conversely, however, if one does not optimize contrast administration to take advantage of differences in blood flow between liver parenchyma and liver neoplasms, potentially tumors can be obscured at imaging. The focus of this article will be to review the physiology of liver blood flow and how various methods of contrast material administration can be used to optimize CT liver tumor detection and characterization.
    Rays 01/1997; 22(2):270-94.
  • M S Peterson · R L Baron · T Murakami
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    ABSTRACT: To determine whether liver tumor detection is increased by acquiring multiple dynamic arterial phase and portal venous phase magnetic resonance (MR) images. Dynamic MR imaging was performed in 205 patients at 1.5 T with use of a fast spoiled gradient-echo technique (repetition time, 9-12 msec; echo time, 2.1-3.0 msec; flip angle, 30 degrees). During intravenous bolus injection of gadopentetate dimeglumine or gadoteridol (0.1 mmol/kg), nine images were acquired at each of 10-12 locations over approximately 120 seconds. The number of tumors detected on arterial phase and portal venous phase images and unenhanced T1- and T2-weighted spin-echo (SE) images was evaluated separately. Data obtained in 75 patients with proved malignancies were analyzed. At imaging, 220 malignant tumor nodules were depicted. At prospective review of all images, 110 hepatocellular carcinomas (HCCs) were detected: 82 (75%) on unenhanced T1-weighted SE images, 83 (75%) on unenhanced T2-weighted SE images, 92 (84%) on arterial phase images, and 76 (69%) on portal venous phase images. At prospective review, eight HCCs were detected on only arterial phase images, one on only portal venous phase images, nine on both arterial and portal venous phase images, and 11 on only unenhanced SE images. The 18 additional HCCS detected prospectively on only dynamic images increased HCC detection by 21% over prospective detection on only SE images. Detection of non-HCC tumors (including metastases) did not increase with dynamic images. Acquisition of multiple dynamic arterial phase and portal venous phase images increased detection of HCC but not metastases.
    Radiology 12/1996; 201(2):337-45. DOI:10.1148/radiology.201.2.8888220 · 6.87 Impact Factor
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    ABSTRACT: Because most radiologists in the United States have been taught that fluoroscopy and computed tomography (CT) are the best guidance techniques for nonvascular interventional procedures, sonography has been greatly underused in this regard. Recently, sonography has been gaining recognition as a highly useful and versatile guidance technique. It has many advantages over CT and fluoroscopic guidance, including real-time imaging with vessel visualization, decreased procedure time and cost, portability, and lack of ionizing radiation. Sonography should be the primary guidance technique for many nonvascular interventional procedures, and use of sonography as an adjunct guidance technique increases the ease and speed with which many other interventional procedures are performed. Sonography should generally be used instead of CT for guidance of abdominal and pelvic biopsy and drainage. Sonographic guidance should replace CT and fluoroscopic guidance for biopsy and drainage of accessible peripheral thoracic and mediastinal masses. Use of sonographic guidance should be integrated into all interventional radiology suites to reduce radiation exposure and facilitate the performance of many nonvascular and some vascular interventional procedures that have traditionally been performed under fluoroscopic guidance.
    Radiographics 12/1996; 16(6):1271-88. DOI:10.1148/radiographics.16.6.8946535 · 2.60 Impact Factor
  • J H Oliver · R L Baron
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    ABSTRACT: Helical biphasic contrast-enhanced CT represents a considerable improvement in the detection of vascular liver neoplasms. When properly performed and with an awareness of the pitfalls in timing and associated pseudolesions, this technique substantially increases tumor detection and staging.
    Radiology 11/1996; 201(1):1-14. DOI:10.1148/radiology.201.1.8816509 · 6.87 Impact Factor
  • J H Oliver · R L Baron · M P Federle · H E Rockette
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    ABSTRACT: Because rates of detection of hypervascular neoplasms by conventional dynamic incremental-bolus CT are lower than rates of detection of hypovascular tumors by CT and because both unenhanced CT imaging and arterial phase helical CT imaging may increase the detection of hypervascular tumors, such as hepatocellular carcinoma, we evaluated the value of unenhanced and arterial phase CT imaging used in conjunction with conventional portal venous phase CT imaging in patients with hepatocellular carcinoma. Unenhanced and biphasic helical contrast-enhanced CT studies were performed on 81 patients with proven hepatocellular carcinoma. Arterial phase and portal venous phase images were obtained at 20-50 sec and at 60-100 sec, respectively. Three blinded readers evaluated portal venous phase images for the number of liver lesions. On separate dates, the readers compared the arterial phase images with the portal venous phase images and the unenhanced images with the portal venous phase images. The readers recorded the number of lesions that were seen on portal venous phase images and that were also detected on unenhanced or arterial phase images as well as the number of additional lesions seen on unenhanced or arterial phase images. Consensus readings of unenhanced, arterial phase, and portal venous phase images were obtained in the 42 patients who had definitive surgery or follow-up CT scans, documenting the total tumor burden in this patient subgroup. The readers identified 286-310 lesions on portal venous phase images. On unenhanced images, the readers identified 223-244 of the lesions seen on portal venous phase images and an additional 45-55 lesions that were not seen on portal venous phase images. Arterial phase imaging revealed 245-269 of the lesions seen on portal venous phase images and an additional 89-111 lesions that were not seen on portal venous images. The diagnosis of tumor was possible only on unenhanced images in two (3%) of 81 patients and only on arterial phase images in seven patients (9%). In the subset of 42 patients with proof of tumor burden, 157 proven lesions were found. Consensus readings identified 127 (81%) of these lesions on portal venous phase images, 98 (62%) of these lesions on unenhanced images, and 120 (76%) of these lesions on arterial phase images. Of the 30 lesions not seen on portal venous phase images, nine were seen on both unenhanced and arterial phase images, three were seen on unenhanced images only, and 18 were seen on arterial phase images only. In patients with known or suspected hepatocellular carcinoma, the use of unenhanced or arterial phase images or both in addition to conventional portal venous phase images resulted in more tumors being detected. The combination of arterial phase and portal venous phase images revealed significantly more hepatocellular carcinoma lesions than did the combination of unenhanced and portal venous phase images.
    American Journal of Roentgenology 08/1996; 167(1):71-7. DOI:10.2214/ajr.167.1.8659425 · 2.73 Impact Factor
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    ABSTRACT: To determine the efficacy of manganese (II) N,N'-dipyridoxylethylenediamine-N,N'-diacetate 5,5'-bis(phosphate) (DPDP) at magnetic resonance (MR) imaging for evaluation of hepatocellular carcinoma (HCC). MR imaging at 1.5 T was performed in 20 patients with 65 HCC nodules. T1- and T2-weighted spin-echo and T1-weighted gradient-recalled-echo images were obtained before and after administration of 5 mumol/kg Mn-DPDP. Readers individually evaluated the pre- and postcontrast images for detection of tumor nodules, with subsequent consensus reading for interpretation discrepancies. Quantitative measurements of tumor-liver contrast-to-noise ratio (C/N) were also performed. Enhancement characteristics were correlated with histologic tumor differentiation. Precontrast images depicted 50 lesions in 17 patients, and postcontrast images depicted 49 lesions in 20 patients. Combination of pre- and postcontrast images enabled detection of 53 lesions in 20 patients. Three lesions (three patients) were seen only on postcontrast images. Four lesions (three patients) were seen only on precontrast images. Reader evaluation of tumor conspicuity showed a significant preference for precontrast T2-weighted SE images (P < .01). Quantitative evaluation showed a significant increase in C/N on postcontrast T1-weighted images (P < .01). Well-differentiated lesions showed significantly greater enhancement than that of poorly differentiated lesions (P < .05). Mn-DPDP-enhanced MR imaging depicts HCC tumors not visualized with unenhanced studies. The degree of tumor enhancement correlates with histologic differentiation.
    Radiology 07/1996; 200(1):69-77. DOI:10.1148/radiology.200.1.8657947 · 6.87 Impact Factor

Publication Stats

2k Citations
233.50 Total Impact Points


  • 1992–2001
    • University of Pittsburgh
      • • Department of Radiology
      • • Department of Medicine
      Pittsburgh, PA, United States
  • 1997
    • University of Texas Health Science Center at San Antonio
      • Department of Radiology
      San Antonio, Texas, United States