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P J Mergo

Publications and source records attributed to P J Mergo.

35 records · Page 2Linked to original sources
PubMed1996

The leaking esophagus: CT patterns of esophageal rupture, perforation, and fistulization.

Esophageal perforation can be a catastrophic event for a patient regardless of the etiology of the perforation. Contrast esophagrams can typically diagnose an esophageal perforation if the clinical symptoms or history suggest the diagnosis. Often, however, the clinical features are atypical and a CT scan is performed early in the patient's workup. It is, therefore, essential to recognize the CT features seen in esophageal perforation. The various etiologies and CT findings of esophageal perforation are reviewed in this article. The CT abnormalities include extraluminal air, periesophageal fluid, esophageal thickening, and extraluminal contrast. These CT findings may be the first clue to the correct diagnosis of esophageal perforation.

Esophageal Fistula↗
PubMed1995

Iliopsoas compartment: normal anatomy and pathologic processes.

The iliopsoas compartment is an extraperitoneal space that contains the greater psoas, smaller psoas, and iliac muscles. Many pathologic processes may involve the iliopsoas compartment, including inflammatory, hemorrhagic, and neoplastic conditions. Psoas muscle infection is usually due to direct extension from contiguous structures. With the decreasing incidence of tuberculosis, the majority of psoas abscesses now encountered have a pyogenic origin. Hemorrhage into the psoas muscle can be spontaneous or secondary to various conditions. Neoplastic involvement of the psoas muscle is usually due to contiguous spread and is rarely primary. With the refinement of imaging modalities, there has been increased recognition of diseases that involve the iliopsoas compartment. Although these conditions may look similar radiologically, they can be correctly diagnosed by combining the radiologic findings with the clinical history. Biopsy is effective in diagnosis of such conditions; aspiration and drainage are effective in both diagnosis and therapy.

Abscess↗
PubMed1995

MR imaging of the spleen.

MR imaging is used in the spleen primarily to supplement CT scan studies. Because of its multiplanar capabilities and potential characterization of lesions on the basis of signal features, however, MR can provide important diagnostic information. This article reviews appropriate imaging techniques and the MR appearance of congenital anomalies, trauma, inflammatory and vascular disease, and neoplasms.

Humans↗
PubMed1994

Diffuse disease of the liver: radiologic-pathologic correlation.

Cross-sectional imaging is playing an increasing role in diagnosis of diffuse liver diseases because it clarifies, in many cases, the overlap in clinical and laboratory manifestations often present in diffuse hepatic processes and thus may eliminate the need for a biopsy. Advances in cross-sectional imaging, particularly in magnetic resonance (MR) imaging, enable further characterization of hepatic parenchymal and architectural changes, allowing closer correlation with underlying pathologic changes. Advanced imaging techniques can be used to characterize a variety of metabolic, vascular, toxic, infectious, and neoplastic diffuse liver diseases. These include more common entities such as cirrhosis, Budd-Chiari syndrome, hemochromatosis, Wilson disease, fatty change, and diffuse neoplastic disease (hepatocellular carcinoma, metastasis, and lymphoma) and uncommon entities such as schistosomiasis, sarcoidosis, and amyloidosis. Correlation of computed tomographic and MR imaging findings with underlying pathologic features is helpful in understanding the gamut of diffuse diseases of the liver.

Amyloidosis↗
PubMedDate not supplied

MRI in focal liver disease: a comparison of small and ultra-small superparamagnetic iron oxide as hepatic contrast agents.

The purpose of this study was to compare small and ultrasmall superparamagnetic iron oxide particles (SPIO and USPIO, respectively) as MR contrast agents for the evaluation of focal hepatic disease. In two different patient groups (SPIO [n = 53], USPIO [n = 27]), with focal liver disease (metastases, hepatocellular carcinoma [HCC], hepatocellular adenoma [HCA], and focal nodular hyperplasia [FNH]), spin-echo T1- and T2-weighted images (T1WI, T2WI) were obtained at 1.0T, before and after intravenous contrast administration. The percentage signal-to-noise ratio (SNR) change and lesion-to-liver contrast (LLC) were measured and statistically compared. The liver decreased in signal intensity (SI) after SPIO administration (-28%) and increased after USPIO administration (+16%) on T1WI. On T2WI, the liver decreased in SI on postcontrast images with both agents (-78% SPIO, -73% USPIO). This difference was not statistically significantly different (P < or = .07). Both SPIO and USPIO provided >500% improvement in LLC on T2WI. On T1WI, LLC was increased in metastases (120%) and HCC (325%) with SPIO. Post-USPIO, LLC was increased on T1WI only in metastases (>500%). Both SPIO and USPIO show excellent hepatic uptake, presumed secondary to reticuloendothelial activity, based on the degree of %SI change seen in the liver after administration of contrast on T2WI. However, USPIO preparations exhibit blood pool activity that may aid in further characterization of focal liver lesions, as is evidenced by their greater T1 effect in the liver and in some focal liver lesions.

Adenoma, Liver Cell↗
PubMedDate not supplied

Lipomatous hypertrophy of the atrial septum: diagnosis with fat suppressed MR imaging.

We present a case of a 50-year-old female evaluated for a 1-year history of numbness of the first and second toe of the right foot. Echocardiography performed in order to exclude cardiovascular compromise revealed a granular mass originating from the posterior part of the interatrial septum. On subsequent magnetic resonance imaging (MRI) with fat suppression sequences, the final diagnosis of lipomatous hypertrophy of the interatrial septum, a benign and underrecognized condition characterized by septal accumulation of fatty tissue, was made. Although no previous reports have focused on this, tailored cardiac MR with fat suppression sequences proved to be an excellent noninvasive method in assessing an accurate diagnosis and in differentiating lipomatous hypertrophy of the atrial septum from other cardiac neoplasms.

Cardiomegaly↗
PubMedDate not supplied

Multiple hepatorenal angiomyolipomas: diagnosis with fat suppression, gadolinium-enhanced MRI.

Hepatic angiomyolipoma is a rare tumor which may occur as a solitary mass or as an associated finding with tuberous sclerosis. While computed tomography allows identification of the fat component of the lesion, magnetic resonance imaging (MRI) can provide similar information, as well as multiplanar visualization and further characterization of the vascular component of the lesion. MRI utilizing fat suppression and gadolinium enhancement may best provide all of the above information, as is demonstrated in this case report, thus potentially representing the imaging modality of choice.

Angiomyolipoma↗
PubMedDate not supplied

Renal and perirenal space involvement in acute pancreatitis: spiral CT findings.

BACKGROUND: This study was conducted to estimate the prevalence and morphologic computed tomographic (CT) features of renal and perirenal space abnormalities in acute pancreatitis in correlation with the severity of pancreatitis. METHODS: One hundred fifty-nine contrast-enhanced CT scans of 100 consecutive patients with acute pancreatitis were retrospectively and independently reviewed by three observers. All CT images were obtained using contrast-enhanced helical CT (collimation width = 5 mm, table increment = 7 mm/s, reconstruction interval = 5 mm, scan delay time = 30-50 s). Additional maximized images (field of view = 260 mm) of the perirenal space were available for review. All CT scans were scored with the CT Severity Score Index: pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the severity score and the presence of renal and perirenal involvement was calculated. Correlation between the prevalence of complications and the degree of pancreatitis was estimated. RESULTS: CT scans were graded as mild (n = 59), moderate (n = 82), and severe (n = 18). Abnormalities detected included perirenal stranding (n = 37 patients, 26 bilateral), perirenal fluid collections (n = 10 patients, one bilateral), ureteral encasement (n = 2 patients), renal vein thrombosis (n = 1 patient), and renal parenchymal abnormalities (n = 1 patient). The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of abnormalities was 75.5-79.2% and 59.8-100%, respectively. Except for stranding of the perirenal fat, no statistically significant differences between the presence of abnormalities and the severity of pancreatitis (moderate or severe) was observed with Fisher's exact test. Also, no preferential left-sided localization of complications was observed. CONCLUSIONS: The incidence of renal and perirenal complications from acute pancreatitis is higher than previously estimated (7%). We found no significant correlation between the prevalence of major complications and the severity of pancreatitis. These findings are important because these complications may have an impact on therapeutic strategy and can affect prognosis.

Acute Disease↗
PubMedDate not supplied

MRI of the breast in the differential diagnosis of mastitis versus inflammatory carcinoma and follow-up.

PURPOSE: Our goal was to evaluate the potential of dynamic MRI in differentiating mastitis and inflammatory breast carcinoma. Furthermore, we evaluated the potential of breast MRI to follow up mastitis patients under antibiotic treatment. METHOD: Twenty-one cases of dynamic breast MR (11 mastitis, 10 inflammatory carcinomas) were reviewed. All patients had a history consistent with either mastitis or inflammatory breast carcinoma. The final diagnosis was histologically confirmed. RESULTS: Ninety percent of the inflammatory carcinomas were found to enhance > 100% in the first minute compared with 55% for mastitis. There is no significant difference between mastitis and inflammatory carcinoma. CONCLUSION: While breast MR cannot currently be used definitively to distinguish inflammatory carcinoma from mastitis, the differences in dynamic enhancement may prove to be useful in follow-up of presumed mastitis in problematic cases. If after biopsy the diagnosis remains unclear, breast MR may help to (a) demonstrate the success of the antibiotic treatment and (b) diagnose coexisting or confounding inflammatory carcinoma.

Adenocarcinoma↗
PubMedDate not supplied

Rectal perflubron: new application in MRI of perirectal fistulae.

PURPOSE: Our goal was to determine the efficacy of MRI with rectal administration of perflubron in the evaluation of perirectal and pelvic fistulae, with an emphasis on development of an improved method for fistula visualization. METHOD: Fourteen pelvic and/or perirectal fistulae were evaluated in nine patients with MRI after the rectal administration of 200 ml of perflubron. Images were reviewed by two independent readers and evaluated for the presence or absence of fistulae. Qualitative assessment was also performed, rating the examinations for the ability to visualize the fistulae. Comparison was made with the clinical examination and/or operative findings, as well as available preperflubron imaging studies (CT = 10; fluoroscopy = 1; preperflubron MRI = 4). RESULTS: MRI with rectal perflubron demonstrated all 14 fistulae (100%), while preperflubron imaging demonstrated only 7 of 14 (50%) fistulae (p < or = 0.008, Wilcoxon signed rank test). In addition, MRI with perflubron resulted in significantly improved qualitative visualization of fistulae (overall very good rating versus poor rating for preperflubron imaging, p < or = 0.006, Wilcoxon signed rank test). CONCLUSION: MRI with rectal perflubron is a superior modality for imaging of fistulae, compared with conventional methods, since it allows a noninvasive means of demonstrating the presence of a fistula as well as offers improved qualitative assessment of fistulous disease.

Administration, Rectal↗
PubMedDate not supplied

Improved technique for pancreatic MRI: value of oblique fat suppression imaging with oral barium administration.

PURPOSE: Our goal was to determine the efficacy of a dedicated protocol for pancreatic MRI using fat suppression, oblique plane orientation, and barium as an oral contrast agent. METHOD: Fifty-two patients were enrolled in our study. In each patient, the stomach and duodenum were opacified with 300 ml oral barium. In all patients conventional SE T1- and T2-weighted images and fat-suppressed axial and oblique T1-weighted images of the upper abdomen and the pancreas, respectively, were obtained. The different T1-weighted sequences were compared for visualization of the pancreas and for lesion conspicuity. Oblique images were obtained in a plane parallel to the overall axis of the pancreas. All sequences were qualitatively assessed by two independent blinded readers and statistically compared. RESULTS: The combination of fat suppression and oblique imaging significantly improved the visualization of the different anatomic portions of the normal pancreas as well as pathologic findings in the pancreas in 70-92% of the cases compared with conventional axial T1-weighted imaging (p < 0.001) and in 52-75% of the cases compared with axial fat-suppressed T1-weighted imaging (p < 0.001), respectively. Increased image noise and blurring artifacts resulted in slight image degradation after Gd-DTPA administration. Barium as a duodenal contrast agent was beneficial for delineation of the pancreatic head from the adjacent bowel structures. CONCLUSION: In pancreatic imaging, fat-suppressed T1-weighted imaging is superior to conventional T1-weighted imaging, and oblique imaging is superior to axial imaging. Intravenous Gd-DTPA administration was useful only in selected cases.

Adipose Tissue↗
PubMedDate not supplied

Dynamic gadolinium-enhanced MR findings in infantile hepatic hemangioendothelioma.

We report a case of a 2 1/2-year-old girl presenting with abdominal pain, fever, vomiting, and hepatomegaly. In spite of the unusual age at presentation, dynamic gadolinium-enhanced MR findings, which have not been previously illustrated, proved to be highly specific for the diagnosis of infantile hepatic hemangioendothelioma because of the characteristic enhancement pattern.

Child, Preschool↗
PubMedDate not supplied

Bilateral adrenal cystic lymphangiomas in nevoid basal cell carcinoma (Gorlin-Goltz) syndrome: US, CT, and MR findings.

We present a case of bilateral adrenal cystic lymphangioma in a patient with the Gorlin-Goltz syndrome. This case is unique as it is the first illustrated case (US, CT, and MR findings) of a cystic lymphangioma arising within the adrenal gland. In addition, the coexistence of cystic adrenal lymphangioma with the Gorlin-Goltz syndrome has not been described previously.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

Perineal angiomyofibroblastoma: CT and MR findings with pathologic correlation.

We present a case of a perineal angiomyofibroblastoma (AMFB) arising in the right perirectal fossa in a middle-aged woman, documented with CT and MRI. Compounding the rarity of the entity, this case is unique as it is the first radiological report illustrating the CT and MR features of this recently clinicopathologically described neoplasm.

Angiofibroma↗
PubMedDate not supplied

Splenic and perisplenic involvement in acute pancreatitis: determination of prevalence and morphologic helical CT features.

PURPOSE: The purpose of this work was to determine the prevalence and morphologic helical CT features of splenic and perisplenic involvement in patients with acute pancreatic inflammatory disease in correlation with the severity of the pancreatitis. METHOD: One hundred fifty-nine contrast-enhanced helical CT scans of 100 consecutive patients with acute pancreatitis were reviewed retrospectively and independently by three observers. CT scans were scored using the CT severity index (CTSI): Pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the CTSI and the presence of splenic and perisplenic involvement was calculated (K statistic). Correlation between the prevalence of complications and the degree of pancreatitis was estimated using the Fisher exact test. RESULTS: The severity of pancreatitis was graded as mild (n = 59 scans), moderate (n = 82 scans), and severe (n = 18 scans). Splenic and perisplenic abnormalities detected included perisplenic inflammatory fluid collections (95 scans, 58 patients), narrowing of the splenic vein (35 scans, 25 patients), splenic vein thrombosis (31 scans, 19 patients), splenic infarction (10 scans, 7 patients), and subcapsular hemorrhage (2 scans, 2 patients). No cases of splenic artery pseudoaneurysm formation, intrasplenic venous thrombosis, intrasplenic pseudocysts, or abscesses were detected. The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of abnormalities was 75.5-79.2 and 71.7-100%, respectively. A statistically significant difference between the presence of abnormalities and the severity of pancreatitis was observed (p < 0.001). CONCLUSION: Splenic vein thrombosis (19%) and splenic infarction (7%) are relatively common CT findings in association with acute pancreatitis. The CTSI proves to be accurate in predicting these complications as there is a statistically significant correlation between the prevalence of these complications and the severity of pancreatitis.

Acute Disease↗
PubMedDate not supplied

Pancreatic neoplasms: MR imaging and pathologic correlation.

Magnetic resonance (MR) imaging can aid in the detection and characterization of many pancreatic neoplasms. The MR imaging appearances of common pancreatic neoplasms such as ductal adenocarcinoma are well-known. However, MR imaging features of more unusual pancreatic neoplasms are not well understood. Such tumors include mucin-hyper-secreting carcinoma, serous microcystic neoplasm, mucinous macrocystic neoplasm, solid and papillary epithelial neoplasm, multiple cysts associated with von Hippel-Lindau disease, acinar cell carcinoma, pancreaticoblastoma, and endocrine neoplasms (eg, nonfunctioning islet cell tumors, insulinoma, and gastrinoma). In general, pancreatic neoplasms demonstrate high signal intensity on T2-weighted images; the signal intensity on T1-weighted images is more variable but is often intermediate or low. Gadolinium enhancement is often helpful in further characterizing pancreatic neoplasms. The gross and histologic features of pancreatic neoplasms are also not well-known. Correlation with the underlying pathologic features enhances understanding of the MR imaging characteristics of both common and unusual pancreatic neoplasms.

Adenocarcinoma, Mucinous↗