Clinical Imaging

2012-01-01

Role of apparent diffusion coefficient values and diffusion-weighted magnetic resonance imaging in differentiation between benign and malignant thyroid nodules

2011-07-18

Abstract: Objective: The purpose of the study was to differentiate between benign and malignant thyroid nodules using nodule-spinal cord signal intensity and nodule apparent diffusion coefficient (ADC) ratios on diffusion-weighted magnetic resonance imaging (DW-MRI).Materials and Methods: Forty-four patients (27 females, 17 males; mean age, 49 years) with nodules who underwent DW-MRI were included in this study. The images were acquired with 0, 50, 400 and 1000 s/mm2 b values. ADC maps were calculated afterwards. Fine needle aspiration biopsies (FNAB) were performed at the same day with DW-MRI acquisition. The diagnosis in patients where malignity was detected after FNAB was confirmed by histopathologic analysis of the operation material. The signal intensities of the spinal cord and the nodule were measured additionally, over b-1000 diffusion-weighted images. Nodule/cord signal intensity (SI) ratios were obtained and the digital values were calculated by dividing to ADC values estimated for each nodule. Statistical analysis was performed.Results: The (nodule SI-cord SI)/nodule ADC ratio is calculated in the DW images, and a statistically significant relationship was found between this ratio and the histopathology of the nodules (P<.001). The ratio was determined as 0.27 in benign and 0.86 in malignant lesions. The result of receiver operating characteristic (ROC) analysis was statistically significant, and the area under curve (100%) was considerably high. The threshold value was calculated as 0.56 according to the ROC analysis. According to this threshold value, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rates for (nodule SI/cord SI)/ADC ratios in differentiating benign from malignant thyroid nodules are calculated as 100%, 97%, 83%, 100%, and 98%, respectively.Conclusion: We have found that (nodule/cord SI)/nodule ADC ratio has the highest values for sensitivity and specificity among the tests defined for characterization of nodules.

Mucoepidermoid carcinoma of the lung: common findings and unusual appearances on CT

Xinchun Li, Weidong Zhang, Xiaomei Wu, Chongpeng Sun, Miaoling Chen, Qingsi Zeng — 2011-09-26

Abstract: Objectives: This study aimed to analyze the computed tomographic (CT) various findings of mucoepidermoid carcinoma of the lung and to improve the diagnostic efficacy for such tumor.Materials and Methods: Sixteen consecutive patients with mucoepidermoid carcinoma of the lung confirmed by pathology were reviewed retrospectively. All the patients had undergone unenhanced and contrast-enhanced examinations; one of them also had undergone 18F-FDG PET/CT examinations.Results: There were 6 males and 10 females with a mean age of 34.1 years.On CT plain scan, 14 out of 16 cases showed a well-defined endobronchus mass (n=12) or single peripheral nodule (n=2) with obstructive pneumonia or atelectasis (n=4), one case appeared a cavity in the tumor mass, and one presented diffuse circumferential wall thickening. Punctate calcification was observed in four cases (25%). Tumors showed mild (n=4, 25 %), moderate (n=6, 37.5%), and marked (n=6, 37.5%) degrees of contrast enhancement. Two patients had mediastinal lymph node metastasis, and one of them also had bone metastasis.Conclusions: Mucoepidermoid carcinoma of the lung likely affects young adults. The common findings included a well-defined ovoid or rounded intraluminal mass; and uncommon findings included cavitation, diffuse thickening, or spiculation. Although CT manifestations of it are variable and nonspecific, a well-defined ovoid or lobulated intraluminal or lung peripheral mass with moderate to marked heterogeneous contrast enhancement may suggest the diagnosis of mucoepidermoid carcinoma of the lung. It should be included in the differential diagnosis of regional tumors.

Pulmonary metastases from colorectal cancer: imaging findings and growth rates at follow-up CT

2011-06-20

Abstract: The objective of the study was to evaluate the computed tomographic (CT) features and growth rates of pulmonary metastases from colorectal cancer (CRC) on serial CT scans. The study included 17 patients (28 pulmonary metastases) who underwent metastasectomy from CRC. The characteristic CT features include well-defined round or oval nodules in the peripheral or subpleural/fissural lung with frequent feeding vessel sign. The mean tumor volume doubling time was calculated as 160 days. With these growth rates, short-term follow-up (i.e., 5–6 months) would be helpful.

Safety and efficacy of image-guided percutaneous biopsies in the diagnosis of gastrointestinal stromal tumors

2011-06-20

Abstract: Background: After the invention of effective target agent therapy for gastrointestinal stromal tumors (GISTs), percutaneous biopsies may be indicated for unresectable diseases or before neoadjuvant chemotherapy. The purpose of this study was to evaluate the safety and efficacy of percutaneous biopsies for GISTs.Material and methods: Fifty-eight procedures of transluminal biopsies or image-guided percutaneous biopsies in 49 patients at our Institution from 1999 to 2010 were retrospectively reviewed.Result: Twenty-three transluminal biopsies, 20 ultrasonography-guided biopsies, and 15 CT-guided biopsies were performed. Failure rate was higher in the group of transluminal biopsies (17%). There is no major procedure-related complication in patients who underwent percutaneous biopsy. However, life-threatening bleeding after transluminal biopsies happened in two patients.Conclusion: Image-guided percutaneous biopsy is a safe and efficient alternative tool for the diagnosis of patients with GISTs.

Ileal adenocarcinoma in Crohn's disease: magnetic resonance enterography features

2011-05-30

Abstract: Patients with Crohn's disease are at increased risk for small bowel adenocarcinoma. We report herein two cases of Crohn's disease-related ileal adenocarcinoma, which were investigated by means of magnetic resonance (MR)-enterography. Two different patterns were observed. In one case, the tumor presented as long circumferential, asymmetric and heterogeneous thickening of the ileum with visible nodule on free induction echo stimulated acquisition images. In the other case, the malignant lesion presented as a tumor mass of the terminal ileum, extending onto the cecum, and showed restricted diffusion on diffusion-weighted MR imaging. In both cases, the tumors were diagnosed preoperatively. Histopathological analysis after surgical resection confirmed T4N1 poorly differentiated mucinous adenocarcinoma of the ileum in association with findings consistent with active in one case and inactive Crohn's disease in the other case. Our observations suggest that MR-enterography may be a useful imaging test for the detection of small bowel adenocarcinoma in patients with Crohn's disease.

Diagnostic power of various computed tomography signs in diagnosing acute appendicitis

2011-05-16

Abstract: Objective: To review the diagnostic power of various computed tomography (CT) signs in acute appendicitis, in particular those initially classified as inconclusive.Materials and methods: Retrospective review of 100 CT abdomen and pelvis studies with assessment of maximal luminal diameter, wall thickness and cross-sectional diameter of the appendix, periappendiceal inflammatory changes, and presence of appendicolith.Results: All CT signs show statistically significant occurrences in acute appendicitis. Their respective cut-off values with best sensitivity and specificity were calculated. Those from the inconclusive cases were also reviewed.Conclusion: Maximal cross-sectional diameter of the appendix is the most powerful parameter. Rest of the CT signs is supportive, especially in cases with inconclusive results.

Transmural colonic ischemia: clinical features and computed tomography findings

2011-04-01

Abstract: Our purpose was to describe the computed tomography features of transmural colonic ischemia in correlation with clinical, laboratory and histopathological findings of 14 patients who underwent colectomy (9 female and 5 male; mean age, 68 years). Seven patients died (50%). Transmural necrosis involved the right colon in 10 patients (10/14, or 72%). Eleven patients showed thickened colonic wall (11/14, or 79%), 10 pneumatosis (10/14, or 71%), 5 gas in the portal venous system (5/14, or 36%), and 14 fat stranding (14/14, or 100%).

Is it possible to differentiate between hydatid and simple cysts in the liver by means of diffusion-weighted magnetic resonance imaging?

2011-05-10

Abstract: Objective: Our aim was to evaluate the contribution of diffusion-weighted imaging to the differentiation of hydatid cysts (HCs) from the simple cysts and to the identification of the HC subtypes.Materials and methods: A total of 37 patients were included in this retrospective study. Fifty of these patients had diagnosed liver cysts (28 HCs and 22 simple cysts) of at least 1 cm in size. All of the cysts were examined with sonography and magnetic resonance imaging, and the HCs were classified according to the World Health Organization criteria.Results: Twenty-eight of the total 50 cysts were HCs, and 22 were simple cysts. When the apparent diffusion coefficient (ADC) values of all HCs were compared with the ADC values of the simple cysts, a statistically significant relationship was found (P=.001). The optimal ADC threshold value was established as 2.5 s/mm2. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy rates were 60%, 95%, 94%, 65% and 76%, respectively.Conclusion: Diffusion-weighted imaging–magnetic resonance imaging is a considerably helpful technique for differentiating between HCs and simple cysts and for differentiating between HC subtypes.

Evaluation of the screening power of Cognitive Abilities Screening Instrument for probable Alzheimer's disease using voxel-based morphometry

Greta S.P. Mok, Yi-Ying Wu, Kun-Mu Lu, Jay Wu, Liang-Kuang Chen, Tung-Hsin Wu — 2011-05-03

Abstract: Objective: The aim of this study was to compare two screening methods, total score of the Cognitive Abilities Screening Instrument (CASIT) and the combined score for the short-term memory and orientation domains (CASIR) for screening and grading probable Alzheimer's disease (AD), based on their correlations with voxel-based morphometry (VBM).Materials and methods: Forty-five subjects with probable AD and normal controls underwent magnetic resonance imaging and CASI testing. Their corresponding T1-weighted magnetic resonance images were analyzed using VBM.Results: VBM results showed that in moderate-to-severe AD subgroups, significant whole-brain gray matter loss was detected using both CASIT and CASIR. Significantly more voxels were detected using the CASIT compared with the CASIR system in mild AD subjects (P<.05).Conclusions: Based on their correlations with VBM results, there is no significant difference for CASIR and CASIT for grading moderate-to-severe AD subgroups, and CASIR scoring system may be more accurate and effective than the CASIT for screening mild AD.

Abdominal complications of chemotherapy: findings at computed tomography

2011-03-25

Abstract: Modern chemotherapy may result in an array of complications that can produce computed tomography (CT) findings in the hepatobiliary, gastrointestinal and urinary systems. This article describes the CT findings that may be seen in abdominal complications of contemporary chemotherapy. Knowledge of the varying CT appearances that can be encountered may facilitate both diagnosis and management in such cases.

Angiocentric glioma in a 4-year-old boy: imaging characteristics and review of the literature

Korgun Koral, Kadriye M. Koral, Fred Sklar — 2011-06-01

Abstract: An angiocentric glioma of the right temporal lobe is presented in a 4-year-old male. Imaging characteristics of this newly codified glial neoplasm are discussed with a review of the literature.

18F-Fluorodeoxyglucose uptake and apparent diffusion coefficient in lung schwannoma

2011-07-18

Abstract: Intrapulmonary schwannoma is uncommon and preoperative radiological diagnosis is rare. Described is a schwannoma that developed as a pulmonary hilar nodule in a 38-year-old woman. The nodule showed strong 18F-fluorodeoxyglucose uptake with a maximum standard uptake value of 5.98 on positron emission tomography and had a high apparent diffusion coefficient (2.5×103 mm2/s) on diffusion-weighted magnetic resonance imaging. Combination of these functional imaging techniques warrants further evaluation in radiological diagnosis of intrapulmonary schwannoma.

Right-side paraduodenal hernia: unexplained recurrent abdominal pain

Chih-Wei Lu, Liang-Chih Liu — 2011-06-30

Abstract: Paraduodenal hernia is a rare congenital malformation. Although it may be an incidental finding at autopsy or at laparotomy, some cases are symptomatic. In such a condition, imaging is mandatory for the diagnosis. In the clinical literature, only a few cases of paraduodenal hernia diagnosed with computed tomography (CT) have been reported. We report two cases of surgically proven right paraduodenal hernia diagnosed preoperatively by multislice helical CT.

Reversible uro-lymphatic fistula

2011-05-25

Abstract: Renal lymphatic fistulas are rare and, in most cases, of parasitic origin. We report a case of a reversible uro-lymphatic fistula, which was demonstrated by CT and was felt to be secondary to a radiolucent calculus.

Intramural vesicular fat — an uncommon CT finding

Raj Ramabhai Patel, Bruce R. Javors — 2011-07-18

Abstract: We present a case of a 75-year-old male who presented with lower back pain found to have an incidental finding of intramural vesicular fat on an unenhanced computed tomography of the pelvis. This relatively uncommon finding of a normal entity should not be mistaken for other causes of pathology within the urinary bladder.

Radiology-pathology conference: primary perinephric and renal extraosseous Ewing's sarcoma

2011-07-18

Abstract: Ewing's sarcoma/primitive neuroectodermal tumor is a rare entity belonging to a family of neoplasms of neuroectodermal origin. These highly aggressive neoplasms overwhelmingly affect children and young adults. A quarter of Ewing's sarcomas occur principally in the soft tissues with primary involvement of the perinephric fat and kidney being exceptionally rare. We present a 38-year-old man with primary Ewing's sarcoma of the perinephric fat and kidney diagnosed 2 years earlier who subsequently developed an infiltrating left renal and perinephric mass.

Case reports

2011-12-02

Eugenio Borsatti — 2011-12-02

Oncological imaging has changed in the last 10 years, from an exclusively morphological assessment towards a metabolic evaluation of disease. This passage was principally due to the widespread use of FDG-positron emission tomography (PET) in cancer management, whose value has had an enormous impact on diagnostic medicine, greater than that of any other nuclear medicine procedure over the last 50 years. Nowadays, FDG-PET is the mainstay of diagnostic oncology, and this textbook, edited by Juweid and Hoekstra, from Iowa (USA) and Amsterdam (The Netherlands), respectively, constitutes a complete review of both consolidated and recent oncological PET applications.

Pietro Torricelli — 2011-11-23

Among the many broad uses for magnetic resonance imaging (MRI) in diagnostic imaging, the abdomen and pelvis are the parts most difficult to handle owing to wide spectrum of technical potential and pathological findings. As stated by the editors in their preface, the authors tried to overcome the gap between reference books and up-to-date MRI applications, in order to provide the practicing radiologist with the appropriate tools to produce and accurately interpret excellent quality examinations in the setting of a busy daily routine. The competence of the authors in the MRI field is well known and documented in the recent literature, and the second edition of this book is awaited as a real quintessence of the clinically relevant information currently available in abdominal and pelvic MRI. Progress in hardware and software affirms MRI as a robust and well-established nonionizing radiation diagnostic tool in abdominal–pelvic imaging by offering qualitative and quantitative information.

Jean Noël Bruneton — 2011-12-02

This book belongs to the very interesting series which, under the title RadCases, presents 12 books dealing with the imaging of different anatomical regions and also with different types of imaging, such as interventional radiology, nuclear medicine, and ultrasonography.

Jean Noël Bruneton — 2011-12-02

Critical Care Radiology answers a need often felt by anesthesiologists and emergency physicians who are often confronted by urgent diagnostic problems shown on standard radiographs, often of poor quality. These problems are still relatively frequent in large hospital centers and in large private clinics. Digitalization and telemedicine have potentially improved the information obtained by imaging performed on a bedridden patient. Nevertheless, it is still true that these types of situations remain preoccupying. Consequently, this kind of book is really useful in helping the clinician rapidly reach certain therapeutic decisions which may be crucial to the prognosis of the patient; and concerning the time necessary for an emergency imaging, as an example, one should keep in mind that computed tomographic examinations require sufficient time just for the transport of the patient.

Antonio F. Govoni — 2011-12-05

This textbook, edited by two very well known gastro-entero-radiologists, is part of a new series, defined by the publisher as high-yield imaging, in which the reader can quickly clear a diagnostic problem, by presenting and discussing the pros and cons of the differential diagnoses of specific gastrointestinal diseases.

Re: Article by Gonoi et al.

Tatsuya Kin, James Shapiro — 2011-09-19

In 2008, Leyendecker and Baginski coined the term “circumportal pancreas” to describe an anatomical variant characterized by complete encirclement of the main portal vein by pancreatic tissue. This variant was not recognized well in the past, but recently, the number of reports describing this variant has increased substantially.

Clinical Imaging

Contents

Role of apparent diffusion coefficient values and diffusion-weighted magnetic resonance imaging in differentiation between benign and malignant thyroid nodules

Mucoepidermoid carcinoma of the lung: common findings and unusual appearances on CT

Pulmonary metastases from colorectal cancer: imaging findings and growth rates at follow-up CT

Safety and efficacy of image-guided percutaneous biopsies in the diagnosis of gastrointestinal stromal tumors

Ileal adenocarcinoma in Crohn's disease: magnetic resonance enterography features

Diagnostic power of various computed tomography signs in diagnosing acute appendicitis

Transmural colonic ischemia: clinical features and computed tomography findings

Is it possible to differentiate between hydatid and simple cysts in the liver by means of diffusion-weighted magnetic resonance imaging?

Evaluation of the screening power of Cognitive Abilities Screening Instrument for probable Alzheimer's disease using voxel-based morphometry

Abdominal complications of chemotherapy: findings at computed tomography

Angiocentric glioma in a 4-year-old boy: imaging characteristics and review of the literature

18F-Fluorodeoxyglucose uptake and apparent diffusion coefficient in lung schwannoma

Right-side paraduodenal hernia: unexplained recurrent abdominal pain

Reversible uro-lymphatic fistula

Intramural vesicular fat — an uncommon CT finding

Radiology-pathology conference: primary perinephric and renal extraosseous Ewing's sarcoma

Case reports

Re: Article by Gonoi et al.