Christine Hoeffel - Academia.edu (original) (raw)
Papers by Christine Hoeffel
World journal of gastroenterology : WJG, Jan 21, 2014
Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant disease linked to a mutation of the ST... more Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant disease linked to a mutation of the STK 11 gene and is characterized by the development of benign hamartomatous polyps in the gastrointestinal tract in association with a hyperpigmentation on the lips and oral mucosa. Patients affected by PJS have an increased risk of developing gastrointestinal and extra-digestive cancer. Malignancy most commonly occurs in the small-bowel. Extra-intestinal malignancies are mostly breast cancer and gynecological tumors or, to a lesser extent, pancreatic cancer. These polyps are also at risk of acute gastrointestinal bleeding, intussusception and bowel obstruction. Recent guidelines recommend regular small-bowel surveillance to reduce these risks associated with PJS. Small-bowel surveillance allows for the detection of large polyps and the further referral of selected PJS patients for endoscopic enteroscopy or surgery. Video capsule endoscopy, double balloon pushed enteroscopy, multidetector ...
Diagnostic and interventional imaging, 2013
To compare the capabilities of apparent diffusion coefficient (ADC) and normalized ADC using the ... more To compare the capabilities of apparent diffusion coefficient (ADC) and normalized ADC using the pancreatic parenchyma as reference organ in the characterization of focal pancreatic lesions. Thirty-six patients with focal pancreatic lesions (malignant, n=18; benign tumors, n=10; focal pancreatitis, n=8) underwent diffusion-weighted MR imaging (DWI) at 1.5-Tesla using 3 b values (b=0, 400, 800 s/mm(2)). Lesion ADC and normalized lesion ADC (defined as the ratio of lesion ADC to apparently normal adjacent pancreas) were compared between lesion types using nonparametric tests. Significant differences in ADC values were found between malignant (1.150 × 10(-3)mm(2)/s) and benign tumors (2.493 × 10(-3)mm(2)/s) (P=0.004) and between benign tumors and mass-forming pancreatitis (1.160 × 10(-3)mm(2)/s) (P=0.0005) but not between malignant tumors and mass-forming pancreatitis (P=0.1092). Using normalized ADC, significant differences were found between malignant tumors (0.933 × 10(-3)mm(2)/s), ...
Journal de radiologie, 2009
The advent of second-generation microbubble ultrasound contrast agents and the development of con... more The advent of second-generation microbubble ultrasound contrast agents and the development of contrast specific ultrasound techniques improved the ability of contrast enhanced ultrasound (CEUS) in detecting and characterizing focal liver lesions, opening new prospects in liver imaging. A Medline search in June 2008 identified 72 published studies that used CEUS in focal liver lesion detection, characterization, and follow-up to monitor tumor ablation procedures and antiangiogenic treatment. The purpose of this paper, based on literature review, is to describe the technical recommendations when using CEUS for liver imaging and to define the different vascular patterns of the most relevant benign and malignant lesions. Diagnostic performance of CEUS and the important clinical indications are also presented and discussed. CEUS is increasingly accepted in clinical use for diagnostic imaging and post-interventional workup liver imaging. It may replace many computed tomography and magneti...
Radiology, 2015
Advances in image quality over the past few years, mainly due to refinements in hardware and coil... more Advances in image quality over the past few years, mainly due to refinements in hardware and coil systems, have made diffusion-weighted ( DW diffusion weighted ) magnetic resonance (MR) imaging a promising technique for the detection and characterization of pancreatic conditions. DW diffusion weighted MR imaging can be routinely implemented in clinical protocols, as it can be performed relatively quickly, does not require administration of gadolinium-based contrast agents, and enables qualitative and quantitative assessment of tissue diffusivity (diffusion coefficients). In this review, acquisition parameters, postprocessing, and quantification methods applied to pancreatic DW diffusion weighted MR imaging will be discussed. The current common clinical uses of DW diffusion weighted MR imaging (ie, pancreatic lesion detection and characterization) and the less-common applications of DW diffusion weighted MR imaging used for the diagnosis of pancreatic parenchymal diseases will be rev...
Critical Reviews in Oncology/Hematology, 2014
Dramatic advances in image quality over the past few years have made diffusion-weighted magnetic ... more Dramatic advances in image quality over the past few years have made diffusion-weighted magnetic resonance imaging (DW-MRI) a promising tool for rectal lesion evaluation. DW-MRI derives its image contrast from differences in the motion of water molecules between tissues. Such imaging can be performed quickly without the need for the administration of exogenous contrast medium. The technique yields qualitative and quantitative information that reflects changes at a cellular level and provides information about tumor cellularity and the integrity of cell membranes. The sensitivity to diffusion is obtained by applying two bipolar diffusion-sensitizing gradients to a standard T2-weighted spin echo sequence. The diffusion-sensitivity can be varied by adjusting the "b-factor", which represents the gradient duration, gradient amplitude and the time interval between the two gradients. The higher the b-value, the greater the signal attenuation from moving water protons. In this review, technical considerations relatively to image acquisition and to quantification methods applied to rectal DW-MRI are discussed. The current clinical applications of DW-MRI, either in the field of inflammatory or neoplastic rectal disease are reviewed. Also, limitations, mainly in terms of persistent lack of standardization or evaluation of tumoral response, and future directions of rectal DW-MRI are discussed. The potential utility of DW-MRI for the evaluation of rectal tumor response is on its way to being admitted but future well-designed and multicenter studies, as well as standardization of DW-MRI, are still required before a consensus can be reached upon how and when to use DW-MRI.
European Radiology
To investigate the role of diffusion-weighted magnetic resonance imaging (DWMRI) in the diagnosis... more To investigate the role of diffusion-weighted magnetic resonance imaging (DWMRI) in the diagnosis of abscess-complicating fistula-in-ano.
Medical Radiology, 2011
Page 1. Nonischemic Colitis Philippe Soyer, Mourad Boudiaf, Youcef Guerrache, Christine Hoeffel, ... more Page 1. Nonischemic Colitis Philippe Soyer, Mourad Boudiaf, Youcef Guerrache, Christine Hoeffel, Xavier Dray, and Patrice Taourel Contents 1 Introduction..... 222 2 CT Technique..... ...
Southern Medical Journal, 1999
We report the case of a 22-year-old woman with a large, bilateral lymphangiomatous cyst originati... more We report the case of a 22-year-old woman with a large, bilateral lymphangiomatous cyst originating from the adrenal glands. Since she was having persistent pain and the diagnosis was uncertain, we did surgery.
Journal of Computer Assisted Tomography, 2014
To qualitatively and quantitatively assess the presentation of hepatic focal nodular hyperplasia ... more To qualitatively and quantitatively assess the presentation of hepatic focal nodular hyperplasia (FNH) at diffusion-weighted magnetic resonance imaging (DWMRI) using multiple high b values. Twenty-five patients with 27 FNHs had liver DWMRI at 1.5 T using free-breathing acquisition and 3 b values (0, 600, 1000 s/mm). Focal nodular hyperplasias were evaluated qualitatively using visual analysis of diffusion-weighted magnetic resonance (DWMR) images and quantitatively using conventional apparent diffusion coefficient (ADC) and normalized ADC measurements. All FNHs (100%) were visible on b0 DWMR images; 26 of the 27 FNHs (96%), on b600 DWMR images; and 21 of the 27 FNHs (78%), on b1000 DWMR images. A total of 18 of the 27 FNHs (67%) exhibited a hyperintense central scar on the b0 DWMR images that remained visible on the b600 and b1000 DWMR images in 6 of the 27 FNHs (22%). Conventional ADC value of FNHs (1.318 × 10 mm/±0.208) was significantly lower than that of adjacent hepatic parenchyma (1.414 × 10 mm/s ± 1.95) (P = 0.0003), although a substantial overlap was found. The use of normalized ADC using the liver as reference organ resulted in a more restricted distribution of ADC values (variation coefficient, 5.3%). Focal nodular hyperplasias show a wide range of morphological features at DWMRI using high b values. Further studies are needed to fully investigate as to what extent normalized ADC may result in better lesion characterization.
European Radiology, 2013
To perform a meta-analysis to determine sensitivity and specificity estimates of helical CT-enter... more To perform a meta-analysis to determine sensitivity and specificity estimates of helical CT-enteroclysis in the detection of small-bowel tumours. A search for relevant articles published from January 1992 to November 2010 was performed. Study design, patient characteristics and 2 × 2 contingency tables were recorded for eligible studies. Heterogeneity was assessed with the I (2) statistic. A bivariate generalised linear random-effects model was used to summarise sensitivity and specificity estimates for small-bowel tumour detection on a per-patient basis. Sensitivity and specificity estimates were compared in different subgroups. Twelve studies (696 patients) were eligible. The mean small-bowel tumour prevalence was 22.6 % (range 7.7-45.8 %). Inter-study heterogeneity was substantial for sensitivity (I (2) = 66.9 %; 95 % CI 28.7-88.5 %) and low for specificity (I (2) = 10.6 %; 95 % CI 0.0-55.0 %). On a per-patient basis, pooled sensitivity was 92.8 % (95 % CI 71.3-98.5 %) and pooled specificity 99.2 % (95 % CI 94.2-99.9 %) for the diagnosis of small-bowel tumour. Subgroup analysis revealed that small-bowel preparation, more than one imaging pass and large volumes (≥2 L) of enteral contrast agent did not improve tumour detection. Our meta-analysis confirms that helical CT-enteroclysis has high degrees of sensitivity and specificity for small-bowel tumour detection. However, our findings reinforce the need for more standardised individual studies.
European Radiology, 2013
To prospectively evaluate magnetic resonance (MR) enterography for detecting mesenteric small-bow... more To prospectively evaluate magnetic resonance (MR) enterography for detecting mesenteric small-bowel tumours (MSBTs) and assess the added value of gadolinium-chelate injection. Over a 2-year period MR enterography examinations of 75 patients (33 men, 42 women; mean age, 53.8 years; range, 19-85) with suspected MSBT were blindly analysed by two readers for the presence of MSBT. Sensitivities, specificities, predictive positive values (PPVs), negative predictive values (NPVs) and accuracies of MR enterography for the detection of MSBT were calculated on per-patient and per-lesion bases. The McNemar test was used to compare sensitivities and specificities of the unenhanced and gadolinium-enhanced sets of MR enterographies. Thirty-seven MSBTs were pathologically confirmed in 26 patients. The mean tolerance score of the examinations was 0.7. On a per-patient basis, sensitivity, specificity, PPV, NPV and accuracy for detection of MSBT were 96 % [95 % CI, 89-100 %], 96 % [90-100 %], 93 % [83-100 %], 98 % [94-100 %] and 96 % [92-100 %], respectively. On a per-lesion basis, sensitivity and PPV were 70 % [56-85 %] and 93 % [83-100 %], respectively. Gadolinium injection yielded higher sensitivities on both bases (P = 0.008). MR enterography is an accurate and well-tolerated imaging modality for detecting MSBT. Intravenous administration of gadolinium-chelate improves sensitivity for MSBT detection. • MR enterography accurately detects mesenteric small bowel tumours. • MR enterography is a well-tolerated imaging technique. • Intravenous administration of gadolinium chelate improves sensitivity for detecting small-bowel tumours.
European Journal of Radiology, 2013
To describe the imaging presentation of carcinoid tumors of the small-bowel at 64-section CT-ente... more To describe the imaging presentation of carcinoid tumors of the small-bowel at 64-section CT-enteroclysis and determine the sensitivity of this technique for tumor detection. The 64-section CT-enteroclysis examinations of 22 patients with histopathologically proven small-bowel carcinoid tumors and those of 6 patients with suspected recurrence after small-bowel resection for carcinoid tumor were reviewed. Images were analyzed with respect to imaging presentation. Sensitivity, specificity, and accuracy, of 64-section CT-enteroclysis for the diagnosis of carcinoid tumor of the small-bowel were estimated with 95% confidence intervals (CIs). Twenty-five carcinoid tumors were confirmed in 22 patients (prevalence, 22/28; 79%). Overall sensitivity for carcinoid tumor detection was 76% (19/25; 95%CI: 55-91%) on a per-lesion basis. On a per-patient basis, 64-section CT-enteroclysis had a sensitivity of 86% (19/22; 95%CI: 65-97%), a specificity of 100% (6/6; 95%CI: 54-100%) and an accuracy of 89% (25/28; 95%CI: 72-98%) for the diagnosis of carcinoid tumor. Focal small-bowel wall thickening, mesenteric stranding, and mesenteric mass were found in 20/22 (91%), 18/22 (82%) and 15/22 (68%) patients with pathologically confirmed tumors. 64-Section CT-enteroclysis shows highly suggestive features for the diagnosis of carcinoid tumor of the small-bowel and achieves high degrees of sensitivity for tumor detection.
Digestive Diseases and Sciences, 2009
The purpose of our study was to prospectively compare unenhanced ultrasonography (US) to contrast... more The purpose of our study was to prospectively compare unenhanced ultrasonography (US) to contrast-enhanced US (CEUS) in the detection of hepatic metastases from carcinoid tumor. Thirty patients with carcinoid tumor prospectively underwent US, CEUS, and magnetic resonance imaging (MRI). Differences in sensitivity at US and CEUS were compared using a combination of the results of MR imaging, fine-needle biopsy, and follow-up imaging. Lesion conspicuity was assessed subjectively for US and CEUS. Seventeen patients had a total of 69 hepatic metastases. The addition of CEUS improved the detection of individual metastases from 47 (Se 68%; 95% CI: 57.0, 79.0) to 68 (Se 99%; 99% CI: 96.7, 100.0). Contrast enhancement improved the subjective conspicuity of metastases in 85% of patients. CEUS showed one more metastasis than did MRI in one patient, and MRI showed one more than did CEUS in one patient. CEUS is more sensitive than US in the detection of carcinoid liver metastases.
Critical Reviews in Oncology/Hematology, 2009
Response evaluation in solid tumours currently uses radiological imaging techniques to measure ch... more Response evaluation in solid tumours currently uses radiological imaging techniques to measure changes under treatment. Imaging requires a well-defined anatomical lesion to be viewed and relies on the measurement of a reduction in tumour size during treatment as the basis for presumed clinical benefit. However, with the development of anti-angiogenesis agents, anatomical imaging has became inappropriate as certain tumours would not reduce in size. Functional studies are therefore necessary and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI), DCE-computed tomography (CT) and DCE-ultrasonography (US) are currently being evaluated for monitoring treatments. Diffusion-weighted MR imaging (DW-MRI) and magnetic resonance spectroscopy (MRS) are also capable of detecting changes in cell density and metabolite content within tumours. In this article, we review anatomical and functional criteria currently used for monitoring therapy. We review the published data on DCE-MRI, DCE-CT, DCE-US, DW-MRI and MRS. This literature review covers the following area: basic principles of the technique, clinical studies, reproducibility and repeatability, limits and perspectives in monitoring therapy. Anatomical criteria such as response evaluation criteria in solid tumours (RECIST) will require adaptation to employ not only new tools but also different complementary techniques such as functional imaging in order to monitor therapeutic effects of conventional and new anti-cancer agents.
Critical Reviews in Oncology/Hematology, 2009
This article summarizes the recent advances in radiological imaging in the hepatogastrointestinal... more This article summarizes the recent advances in radiological imaging in the hepatogastrointestinal field in terms of detection, characterization and staging of tumors. Introduction of multidetector row computed tomography technology has helped computed tomography to excel in its already established indications, and has expanded its capabilities by adding new clinical applications, such as computed tomography angiography, liver perfusion, computed tomography enterography or enteroclysis, and virtual colonoscopy. Contrast-enhanced ultrasound has dramatically changed the role of ultrasound in liver tumor characterization, detection, and other applications. Combining the advantages of unsurpassed soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging of the gastrointestinal tract has become increasingly used clinically. Moreover, substantial progress in molecular and cellular magnetic resonance imaging has been achieved in the past few years. Particularly, the increasing number of available specific contrast agents dedicated to the evaluation of the liver and lymph nodes shows promises in the area of oncologic abdominal imaging.
Critical Reviews in Oncology/Hematology, 2011
This article describes the recent advances in radiological imaging of malignant neoplasms of the ... more This article describes the recent advances in radiological imaging of malignant neoplasms of the mesenteric small bowel and provides an outline of new trends and perspectives that can be anticipated. The introduction of multidetector row technology, which allows the acquisition of submillimeter and isotropic voxels, has dramatically improved the capabilities of computed tomography in the investigation of the mesenteric small bowel. This technology combined with optimal filling of small bowel loops through the use of appropriate enteral contrast agents has markedly changed small bowel imaging. Computed tomography-enteroclysis, which is based on direct infusion of enteral contrast agent into the mesenteric small bowel through a naso-jejunal tube, provides optimal luminal distension. By contrast, computed tomography-enterography is based on oral administration of enteral contrast agent. These two techniques are now well-established ones for the detection and the characterization of small bowel neoplasms. During the same time, combining the advantages of unsurpassed soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging has gained wide acceptance for the evaluation of patients with suspected small bowel neoplasms. Rapid magnetic resonance imaging sequences used in combination with specific enteral contrast agents generate superb images of the mesenteric small bowel so that magnetic resonance-enteroclysis and magnetic resonance-enterography are now considered as effective diagnostic tools for both the detection and the characterization of neoplasms of the mesenteric small bowel. Recent improvements in image post-processing capabilities help obtain realistic three-dimensional representations of tumors and virtual enteroscopic views of the small bowel that are useful for the surgeon and the gastroenteroenteologist to plan surgical or endoscopic interventions. Along with a better knowledge of the potential and limitations of wireless capsule endoscopy and new endoscopic techniques, these recent developments in radiological imaging reasonably suggest that substantial changes in the investigation of small bowel tumors may be anticipated in a near future, thus potentially create a new paradigm shift after standard small bowel follow-through study has been universally abandoned.
Clinical Imaging, 2014
Solid-pseudopapillary tumor (SPT) of the pancreas is a rare, low-grade malignancy, which mostly o... more Solid-pseudopapillary tumor (SPT) of the pancreas is a rare, low-grade malignancy, which mostly occurs in adolescent and young adult females. The goal of this study was to retrospectively analyze the magnetic resonance (MR) imaging presentation of SPT of the pancreas. We retrospectively reviewed the preoperative MR imaging examinations and the medical, surgical and histopathological records of 21 patients who underwent surgery for SPT of the pancreas. MR imaging included T1-weighted, T2-weighted, and gadolinium chelate-enhanced MR imaging. In addition, 10 patients had diffusion-weighted (DW) MR imaging. MR examinations were retrospectively reviewed for location, size, morphological features and signal intensity of the tumors. Nineteen women and 2 men (median age, 23 years; range, 14-59) were included. Seven patients (7/21; 33%) presented with abdominal symptoms. The median largest tumor diameter was 53mm (range, 32-141 mm). SPTs were located in the pancreatic head, body, and tail in 9 (9/21; 43%), 5 (5/21; 24%) and 7 (7/21, 33%) patients, respectively. All patients (21/21; 100%) had a single SPT. SPTs were more frequently oval (12/21; 57%), predominantly solid (12/21; 57%), fully encapsulated (16/21; 76%), larger than 30 mm (21/21; 100%), hypointense on T1-weighted MR images (21/21, 100%), hyperintense on T2-weighted MR images (21/21; 100%) and with an enhancing capsule after gadolinium-chelate administration (21/21; 100%). There is trend of appearance for SPT of the pancreas on MR imaging but that variations may be observed in a number of cases. SPT uniformly presents as a single, well-demarcated and encapsulated pancreatic mass.
Clinical Imaging, 2011
Disease in the abdomen and pelvis is frequent in patients with metastatic melanoma (MM). Multidet... more Disease in the abdomen and pelvis is frequent in patients with metastatic melanoma (MM). Multidetector row computed tomography is the imaging modality of choice for diagnosis and follow-up of MM. However, positron emission tomographic scan may be used as well as other newer imaging modalities, particularly for imaging of the abdominal and pelvic metastases. The aim if this exhibit is to review the distribution and features of melanoma metastases to the abdomen and pelvis as well as the role of currently available imaging modalities.
Clinical Imaging, 2012
The purpose of our article was to review the magnetic resonance imaging (MRI) features of pelvic ... more The purpose of our article was to review the magnetic resonance imaging (MRI) features of pelvic abscesses. Pelvic abscesses account for a wide range of abnormalities from various etiologies. MRI is being increasingly used for pelvic exploration. Radiologists must thus be aware of their features and characteristics.
Abdominal Imaging, 2014
Purpose: To retrospectively analyze the MR imaging features of rectal cancer in patients with inf... more Purpose: To retrospectively analyze the MR imaging features of rectal cancer in patients with inflammatory bowel diseases (IBD). Materials and methods: The MR imaging examinations of 13 patients with IBD-related rectal cancer were retrospectively reviewed. MR imaging included T2weighted, diffusion-weighted (DW), and gadolinium chelate-enhanced MR imaging. MR imaging findings were analyzed and compared with endoscopic and histopathological findings. Results: Eight patients (8/13; 62%) had active IBD and five (5/13; 38%) had quiescent IBD on MR imaging. Two different tumor patterns were individualized including clearly visible soft-tissue mass (4/13; 31%) (Type 1 tumor) and marked circumferential rectal wall thickening (9/13; 69%) (Type 2 tumor). Twelve tumors (12/13; 92%) showed high signal intensity on T2-weighted MR images. All six tumors studied with DW-MR imaging (6/6; 100%) showed high signal on DW-MR imaging with restricted diffusion on apparent diffusion coefficient (ADC) map. On gadolinium chelate-enhanced MR imaging, heterogeneous enhancement was observed in one tumor (1/13; 8%), whereas 12 tumors (12/13; 92%) showed homogeneous enhancement. MR imaging showed pelvic fistula and intrapelvic abscess in association with four (4/13; 31%) and two tumors (2/13; 15%), respectively. Conclusion: Our limited retrospective study demonstrates that rectal cancer in IBD patients can present as a circumferential wall thickening resembling inflammation and can occur in the absence of fistula or abscess. The use of T2-weighted and DW-MR imaging is recommended to improve rectal cancer detection in patients with long-standing IBD.
World journal of gastroenterology : WJG, Jan 21, 2014
Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant disease linked to a mutation of the ST... more Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant disease linked to a mutation of the STK 11 gene and is characterized by the development of benign hamartomatous polyps in the gastrointestinal tract in association with a hyperpigmentation on the lips and oral mucosa. Patients affected by PJS have an increased risk of developing gastrointestinal and extra-digestive cancer. Malignancy most commonly occurs in the small-bowel. Extra-intestinal malignancies are mostly breast cancer and gynecological tumors or, to a lesser extent, pancreatic cancer. These polyps are also at risk of acute gastrointestinal bleeding, intussusception and bowel obstruction. Recent guidelines recommend regular small-bowel surveillance to reduce these risks associated with PJS. Small-bowel surveillance allows for the detection of large polyps and the further referral of selected PJS patients for endoscopic enteroscopy or surgery. Video capsule endoscopy, double balloon pushed enteroscopy, multidetector ...
Diagnostic and interventional imaging, 2013
To compare the capabilities of apparent diffusion coefficient (ADC) and normalized ADC using the ... more To compare the capabilities of apparent diffusion coefficient (ADC) and normalized ADC using the pancreatic parenchyma as reference organ in the characterization of focal pancreatic lesions. Thirty-six patients with focal pancreatic lesions (malignant, n=18; benign tumors, n=10; focal pancreatitis, n=8) underwent diffusion-weighted MR imaging (DWI) at 1.5-Tesla using 3 b values (b=0, 400, 800 s/mm(2)). Lesion ADC and normalized lesion ADC (defined as the ratio of lesion ADC to apparently normal adjacent pancreas) were compared between lesion types using nonparametric tests. Significant differences in ADC values were found between malignant (1.150 × 10(-3)mm(2)/s) and benign tumors (2.493 × 10(-3)mm(2)/s) (P=0.004) and between benign tumors and mass-forming pancreatitis (1.160 × 10(-3)mm(2)/s) (P=0.0005) but not between malignant tumors and mass-forming pancreatitis (P=0.1092). Using normalized ADC, significant differences were found between malignant tumors (0.933 × 10(-3)mm(2)/s), ...
Journal de radiologie, 2009
The advent of second-generation microbubble ultrasound contrast agents and the development of con... more The advent of second-generation microbubble ultrasound contrast agents and the development of contrast specific ultrasound techniques improved the ability of contrast enhanced ultrasound (CEUS) in detecting and characterizing focal liver lesions, opening new prospects in liver imaging. A Medline search in June 2008 identified 72 published studies that used CEUS in focal liver lesion detection, characterization, and follow-up to monitor tumor ablation procedures and antiangiogenic treatment. The purpose of this paper, based on literature review, is to describe the technical recommendations when using CEUS for liver imaging and to define the different vascular patterns of the most relevant benign and malignant lesions. Diagnostic performance of CEUS and the important clinical indications are also presented and discussed. CEUS is increasingly accepted in clinical use for diagnostic imaging and post-interventional workup liver imaging. It may replace many computed tomography and magneti...
Radiology, 2015
Advances in image quality over the past few years, mainly due to refinements in hardware and coil... more Advances in image quality over the past few years, mainly due to refinements in hardware and coil systems, have made diffusion-weighted ( DW diffusion weighted ) magnetic resonance (MR) imaging a promising technique for the detection and characterization of pancreatic conditions. DW diffusion weighted MR imaging can be routinely implemented in clinical protocols, as it can be performed relatively quickly, does not require administration of gadolinium-based contrast agents, and enables qualitative and quantitative assessment of tissue diffusivity (diffusion coefficients). In this review, acquisition parameters, postprocessing, and quantification methods applied to pancreatic DW diffusion weighted MR imaging will be discussed. The current common clinical uses of DW diffusion weighted MR imaging (ie, pancreatic lesion detection and characterization) and the less-common applications of DW diffusion weighted MR imaging used for the diagnosis of pancreatic parenchymal diseases will be rev...
Critical Reviews in Oncology/Hematology, 2014
Dramatic advances in image quality over the past few years have made diffusion-weighted magnetic ... more Dramatic advances in image quality over the past few years have made diffusion-weighted magnetic resonance imaging (DW-MRI) a promising tool for rectal lesion evaluation. DW-MRI derives its image contrast from differences in the motion of water molecules between tissues. Such imaging can be performed quickly without the need for the administration of exogenous contrast medium. The technique yields qualitative and quantitative information that reflects changes at a cellular level and provides information about tumor cellularity and the integrity of cell membranes. The sensitivity to diffusion is obtained by applying two bipolar diffusion-sensitizing gradients to a standard T2-weighted spin echo sequence. The diffusion-sensitivity can be varied by adjusting the "b-factor", which represents the gradient duration, gradient amplitude and the time interval between the two gradients. The higher the b-value, the greater the signal attenuation from moving water protons. In this review, technical considerations relatively to image acquisition and to quantification methods applied to rectal DW-MRI are discussed. The current clinical applications of DW-MRI, either in the field of inflammatory or neoplastic rectal disease are reviewed. Also, limitations, mainly in terms of persistent lack of standardization or evaluation of tumoral response, and future directions of rectal DW-MRI are discussed. The potential utility of DW-MRI for the evaluation of rectal tumor response is on its way to being admitted but future well-designed and multicenter studies, as well as standardization of DW-MRI, are still required before a consensus can be reached upon how and when to use DW-MRI.
European Radiology
To investigate the role of diffusion-weighted magnetic resonance imaging (DWMRI) in the diagnosis... more To investigate the role of diffusion-weighted magnetic resonance imaging (DWMRI) in the diagnosis of abscess-complicating fistula-in-ano.
Medical Radiology, 2011
Page 1. Nonischemic Colitis Philippe Soyer, Mourad Boudiaf, Youcef Guerrache, Christine Hoeffel, ... more Page 1. Nonischemic Colitis Philippe Soyer, Mourad Boudiaf, Youcef Guerrache, Christine Hoeffel, Xavier Dray, and Patrice Taourel Contents 1 Introduction..... 222 2 CT Technique..... ...
Southern Medical Journal, 1999
We report the case of a 22-year-old woman with a large, bilateral lymphangiomatous cyst originati... more We report the case of a 22-year-old woman with a large, bilateral lymphangiomatous cyst originating from the adrenal glands. Since she was having persistent pain and the diagnosis was uncertain, we did surgery.
Journal of Computer Assisted Tomography, 2014
To qualitatively and quantitatively assess the presentation of hepatic focal nodular hyperplasia ... more To qualitatively and quantitatively assess the presentation of hepatic focal nodular hyperplasia (FNH) at diffusion-weighted magnetic resonance imaging (DWMRI) using multiple high b values. Twenty-five patients with 27 FNHs had liver DWMRI at 1.5 T using free-breathing acquisition and 3 b values (0, 600, 1000 s/mm). Focal nodular hyperplasias were evaluated qualitatively using visual analysis of diffusion-weighted magnetic resonance (DWMR) images and quantitatively using conventional apparent diffusion coefficient (ADC) and normalized ADC measurements. All FNHs (100%) were visible on b0 DWMR images; 26 of the 27 FNHs (96%), on b600 DWMR images; and 21 of the 27 FNHs (78%), on b1000 DWMR images. A total of 18 of the 27 FNHs (67%) exhibited a hyperintense central scar on the b0 DWMR images that remained visible on the b600 and b1000 DWMR images in 6 of the 27 FNHs (22%). Conventional ADC value of FNHs (1.318 × 10 mm/±0.208) was significantly lower than that of adjacent hepatic parenchyma (1.414 × 10 mm/s ± 1.95) (P = 0.0003), although a substantial overlap was found. The use of normalized ADC using the liver as reference organ resulted in a more restricted distribution of ADC values (variation coefficient, 5.3%). Focal nodular hyperplasias show a wide range of morphological features at DWMRI using high b values. Further studies are needed to fully investigate as to what extent normalized ADC may result in better lesion characterization.
European Radiology, 2013
To perform a meta-analysis to determine sensitivity and specificity estimates of helical CT-enter... more To perform a meta-analysis to determine sensitivity and specificity estimates of helical CT-enteroclysis in the detection of small-bowel tumours. A search for relevant articles published from January 1992 to November 2010 was performed. Study design, patient characteristics and 2 × 2 contingency tables were recorded for eligible studies. Heterogeneity was assessed with the I (2) statistic. A bivariate generalised linear random-effects model was used to summarise sensitivity and specificity estimates for small-bowel tumour detection on a per-patient basis. Sensitivity and specificity estimates were compared in different subgroups. Twelve studies (696 patients) were eligible. The mean small-bowel tumour prevalence was 22.6 % (range 7.7-45.8 %). Inter-study heterogeneity was substantial for sensitivity (I (2) = 66.9 %; 95 % CI 28.7-88.5 %) and low for specificity (I (2) = 10.6 %; 95 % CI 0.0-55.0 %). On a per-patient basis, pooled sensitivity was 92.8 % (95 % CI 71.3-98.5 %) and pooled specificity 99.2 % (95 % CI 94.2-99.9 %) for the diagnosis of small-bowel tumour. Subgroup analysis revealed that small-bowel preparation, more than one imaging pass and large volumes (≥2 L) of enteral contrast agent did not improve tumour detection. Our meta-analysis confirms that helical CT-enteroclysis has high degrees of sensitivity and specificity for small-bowel tumour detection. However, our findings reinforce the need for more standardised individual studies.
European Radiology, 2013
To prospectively evaluate magnetic resonance (MR) enterography for detecting mesenteric small-bow... more To prospectively evaluate magnetic resonance (MR) enterography for detecting mesenteric small-bowel tumours (MSBTs) and assess the added value of gadolinium-chelate injection. Over a 2-year period MR enterography examinations of 75 patients (33 men, 42 women; mean age, 53.8 years; range, 19-85) with suspected MSBT were blindly analysed by two readers for the presence of MSBT. Sensitivities, specificities, predictive positive values (PPVs), negative predictive values (NPVs) and accuracies of MR enterography for the detection of MSBT were calculated on per-patient and per-lesion bases. The McNemar test was used to compare sensitivities and specificities of the unenhanced and gadolinium-enhanced sets of MR enterographies. Thirty-seven MSBTs were pathologically confirmed in 26 patients. The mean tolerance score of the examinations was 0.7. On a per-patient basis, sensitivity, specificity, PPV, NPV and accuracy for detection of MSBT were 96 % [95 % CI, 89-100 %], 96 % [90-100 %], 93 % [83-100 %], 98 % [94-100 %] and 96 % [92-100 %], respectively. On a per-lesion basis, sensitivity and PPV were 70 % [56-85 %] and 93 % [83-100 %], respectively. Gadolinium injection yielded higher sensitivities on both bases (P = 0.008). MR enterography is an accurate and well-tolerated imaging modality for detecting MSBT. Intravenous administration of gadolinium-chelate improves sensitivity for MSBT detection. • MR enterography accurately detects mesenteric small bowel tumours. • MR enterography is a well-tolerated imaging technique. • Intravenous administration of gadolinium chelate improves sensitivity for detecting small-bowel tumours.
European Journal of Radiology, 2013
To describe the imaging presentation of carcinoid tumors of the small-bowel at 64-section CT-ente... more To describe the imaging presentation of carcinoid tumors of the small-bowel at 64-section CT-enteroclysis and determine the sensitivity of this technique for tumor detection. The 64-section CT-enteroclysis examinations of 22 patients with histopathologically proven small-bowel carcinoid tumors and those of 6 patients with suspected recurrence after small-bowel resection for carcinoid tumor were reviewed. Images were analyzed with respect to imaging presentation. Sensitivity, specificity, and accuracy, of 64-section CT-enteroclysis for the diagnosis of carcinoid tumor of the small-bowel were estimated with 95% confidence intervals (CIs). Twenty-five carcinoid tumors were confirmed in 22 patients (prevalence, 22/28; 79%). Overall sensitivity for carcinoid tumor detection was 76% (19/25; 95%CI: 55-91%) on a per-lesion basis. On a per-patient basis, 64-section CT-enteroclysis had a sensitivity of 86% (19/22; 95%CI: 65-97%), a specificity of 100% (6/6; 95%CI: 54-100%) and an accuracy of 89% (25/28; 95%CI: 72-98%) for the diagnosis of carcinoid tumor. Focal small-bowel wall thickening, mesenteric stranding, and mesenteric mass were found in 20/22 (91%), 18/22 (82%) and 15/22 (68%) patients with pathologically confirmed tumors. 64-Section CT-enteroclysis shows highly suggestive features for the diagnosis of carcinoid tumor of the small-bowel and achieves high degrees of sensitivity for tumor detection.
Digestive Diseases and Sciences, 2009
The purpose of our study was to prospectively compare unenhanced ultrasonography (US) to contrast... more The purpose of our study was to prospectively compare unenhanced ultrasonography (US) to contrast-enhanced US (CEUS) in the detection of hepatic metastases from carcinoid tumor. Thirty patients with carcinoid tumor prospectively underwent US, CEUS, and magnetic resonance imaging (MRI). Differences in sensitivity at US and CEUS were compared using a combination of the results of MR imaging, fine-needle biopsy, and follow-up imaging. Lesion conspicuity was assessed subjectively for US and CEUS. Seventeen patients had a total of 69 hepatic metastases. The addition of CEUS improved the detection of individual metastases from 47 (Se 68%; 95% CI: 57.0, 79.0) to 68 (Se 99%; 99% CI: 96.7, 100.0). Contrast enhancement improved the subjective conspicuity of metastases in 85% of patients. CEUS showed one more metastasis than did MRI in one patient, and MRI showed one more than did CEUS in one patient. CEUS is more sensitive than US in the detection of carcinoid liver metastases.
Critical Reviews in Oncology/Hematology, 2009
Response evaluation in solid tumours currently uses radiological imaging techniques to measure ch... more Response evaluation in solid tumours currently uses radiological imaging techniques to measure changes under treatment. Imaging requires a well-defined anatomical lesion to be viewed and relies on the measurement of a reduction in tumour size during treatment as the basis for presumed clinical benefit. However, with the development of anti-angiogenesis agents, anatomical imaging has became inappropriate as certain tumours would not reduce in size. Functional studies are therefore necessary and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI), DCE-computed tomography (CT) and DCE-ultrasonography (US) are currently being evaluated for monitoring treatments. Diffusion-weighted MR imaging (DW-MRI) and magnetic resonance spectroscopy (MRS) are also capable of detecting changes in cell density and metabolite content within tumours. In this article, we review anatomical and functional criteria currently used for monitoring therapy. We review the published data on DCE-MRI, DCE-CT, DCE-US, DW-MRI and MRS. This literature review covers the following area: basic principles of the technique, clinical studies, reproducibility and repeatability, limits and perspectives in monitoring therapy. Anatomical criteria such as response evaluation criteria in solid tumours (RECIST) will require adaptation to employ not only new tools but also different complementary techniques such as functional imaging in order to monitor therapeutic effects of conventional and new anti-cancer agents.
Critical Reviews in Oncology/Hematology, 2009
This article summarizes the recent advances in radiological imaging in the hepatogastrointestinal... more This article summarizes the recent advances in radiological imaging in the hepatogastrointestinal field in terms of detection, characterization and staging of tumors. Introduction of multidetector row computed tomography technology has helped computed tomography to excel in its already established indications, and has expanded its capabilities by adding new clinical applications, such as computed tomography angiography, liver perfusion, computed tomography enterography or enteroclysis, and virtual colonoscopy. Contrast-enhanced ultrasound has dramatically changed the role of ultrasound in liver tumor characterization, detection, and other applications. Combining the advantages of unsurpassed soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging of the gastrointestinal tract has become increasingly used clinically. Moreover, substantial progress in molecular and cellular magnetic resonance imaging has been achieved in the past few years. Particularly, the increasing number of available specific contrast agents dedicated to the evaluation of the liver and lymph nodes shows promises in the area of oncologic abdominal imaging.
Critical Reviews in Oncology/Hematology, 2011
This article describes the recent advances in radiological imaging of malignant neoplasms of the ... more This article describes the recent advances in radiological imaging of malignant neoplasms of the mesenteric small bowel and provides an outline of new trends and perspectives that can be anticipated. The introduction of multidetector row technology, which allows the acquisition of submillimeter and isotropic voxels, has dramatically improved the capabilities of computed tomography in the investigation of the mesenteric small bowel. This technology combined with optimal filling of small bowel loops through the use of appropriate enteral contrast agents has markedly changed small bowel imaging. Computed tomography-enteroclysis, which is based on direct infusion of enteral contrast agent into the mesenteric small bowel through a naso-jejunal tube, provides optimal luminal distension. By contrast, computed tomography-enterography is based on oral administration of enteral contrast agent. These two techniques are now well-established ones for the detection and the characterization of small bowel neoplasms. During the same time, combining the advantages of unsurpassed soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging has gained wide acceptance for the evaluation of patients with suspected small bowel neoplasms. Rapid magnetic resonance imaging sequences used in combination with specific enteral contrast agents generate superb images of the mesenteric small bowel so that magnetic resonance-enteroclysis and magnetic resonance-enterography are now considered as effective diagnostic tools for both the detection and the characterization of neoplasms of the mesenteric small bowel. Recent improvements in image post-processing capabilities help obtain realistic three-dimensional representations of tumors and virtual enteroscopic views of the small bowel that are useful for the surgeon and the gastroenteroenteologist to plan surgical or endoscopic interventions. Along with a better knowledge of the potential and limitations of wireless capsule endoscopy and new endoscopic techniques, these recent developments in radiological imaging reasonably suggest that substantial changes in the investigation of small bowel tumors may be anticipated in a near future, thus potentially create a new paradigm shift after standard small bowel follow-through study has been universally abandoned.
Clinical Imaging, 2014
Solid-pseudopapillary tumor (SPT) of the pancreas is a rare, low-grade malignancy, which mostly o... more Solid-pseudopapillary tumor (SPT) of the pancreas is a rare, low-grade malignancy, which mostly occurs in adolescent and young adult females. The goal of this study was to retrospectively analyze the magnetic resonance (MR) imaging presentation of SPT of the pancreas. We retrospectively reviewed the preoperative MR imaging examinations and the medical, surgical and histopathological records of 21 patients who underwent surgery for SPT of the pancreas. MR imaging included T1-weighted, T2-weighted, and gadolinium chelate-enhanced MR imaging. In addition, 10 patients had diffusion-weighted (DW) MR imaging. MR examinations were retrospectively reviewed for location, size, morphological features and signal intensity of the tumors. Nineteen women and 2 men (median age, 23 years; range, 14-59) were included. Seven patients (7/21; 33%) presented with abdominal symptoms. The median largest tumor diameter was 53mm (range, 32-141 mm). SPTs were located in the pancreatic head, body, and tail in 9 (9/21; 43%), 5 (5/21; 24%) and 7 (7/21, 33%) patients, respectively. All patients (21/21; 100%) had a single SPT. SPTs were more frequently oval (12/21; 57%), predominantly solid (12/21; 57%), fully encapsulated (16/21; 76%), larger than 30 mm (21/21; 100%), hypointense on T1-weighted MR images (21/21, 100%), hyperintense on T2-weighted MR images (21/21; 100%) and with an enhancing capsule after gadolinium-chelate administration (21/21; 100%). There is trend of appearance for SPT of the pancreas on MR imaging but that variations may be observed in a number of cases. SPT uniformly presents as a single, well-demarcated and encapsulated pancreatic mass.
Clinical Imaging, 2011
Disease in the abdomen and pelvis is frequent in patients with metastatic melanoma (MM). Multidet... more Disease in the abdomen and pelvis is frequent in patients with metastatic melanoma (MM). Multidetector row computed tomography is the imaging modality of choice for diagnosis and follow-up of MM. However, positron emission tomographic scan may be used as well as other newer imaging modalities, particularly for imaging of the abdominal and pelvic metastases. The aim if this exhibit is to review the distribution and features of melanoma metastases to the abdomen and pelvis as well as the role of currently available imaging modalities.
Clinical Imaging, 2012
The purpose of our article was to review the magnetic resonance imaging (MRI) features of pelvic ... more The purpose of our article was to review the magnetic resonance imaging (MRI) features of pelvic abscesses. Pelvic abscesses account for a wide range of abnormalities from various etiologies. MRI is being increasingly used for pelvic exploration. Radiologists must thus be aware of their features and characteristics.
Abdominal Imaging, 2014
Purpose: To retrospectively analyze the MR imaging features of rectal cancer in patients with inf... more Purpose: To retrospectively analyze the MR imaging features of rectal cancer in patients with inflammatory bowel diseases (IBD). Materials and methods: The MR imaging examinations of 13 patients with IBD-related rectal cancer were retrospectively reviewed. MR imaging included T2weighted, diffusion-weighted (DW), and gadolinium chelate-enhanced MR imaging. MR imaging findings were analyzed and compared with endoscopic and histopathological findings. Results: Eight patients (8/13; 62%) had active IBD and five (5/13; 38%) had quiescent IBD on MR imaging. Two different tumor patterns were individualized including clearly visible soft-tissue mass (4/13; 31%) (Type 1 tumor) and marked circumferential rectal wall thickening (9/13; 69%) (Type 2 tumor). Twelve tumors (12/13; 92%) showed high signal intensity on T2-weighted MR images. All six tumors studied with DW-MR imaging (6/6; 100%) showed high signal on DW-MR imaging with restricted diffusion on apparent diffusion coefficient (ADC) map. On gadolinium chelate-enhanced MR imaging, heterogeneous enhancement was observed in one tumor (1/13; 8%), whereas 12 tumors (12/13; 92%) showed homogeneous enhancement. MR imaging showed pelvic fistula and intrapelvic abscess in association with four (4/13; 31%) and two tumors (2/13; 15%), respectively. Conclusion: Our limited retrospective study demonstrates that rectal cancer in IBD patients can present as a circumferential wall thickening resembling inflammation and can occur in the absence of fistula or abscess. The use of T2-weighted and DW-MR imaging is recommended to improve rectal cancer detection in patients with long-standing IBD.