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Introduction: The liver, a vital organ responsible for digestion, detoxification, and receiving rich blood supply from the hepatic artery and portal vein, is susceptible to various diseases, both benign and malignant. The alteration in blood supply patterns serves as the foundation for the triple-phase scan of the liver. Contrast-enhanced triphasic CT, evaluating the organ in arterial, portal venous, and delayed phases, proves instrumental in identifying a spectrum of abnormalities. Methodology: This cross-sectional investigation, conducted at a private medical college and tertiary hospital in Hyderabad, involved administering non-ionic contrast medium to patients with suspected liver illnesses. Arterial phase measurements were taken 35-40 seconds postcontrast administration, showcasing peak hepatic artery-supplied lesions. The portal phase, obtained 70-80 seconds later, proved optimal for evaluating hypo-vascular lesions, while the delayed or equilibrium phase, acquired 5-7 minutes post-contrast injection, offered comprehensive insights. Results: The study revealed that 57% of lesions were hypovascular, more discernible in the portal venous phase, while 43% were hypervascular, exhibiting prominence in the arterial phase. Lesions smaller than 3 cm constituted 43% of cases, those between 3 and 5 cm accounted for 16%, and lesions larger than 5 cm comprised 40%. Notably, lesions smaller than 3 cm demonstrated metastases, predominantly hypo-vascular and visible in the portal phase. Comparisons with Miller et al.'s study on malignant focal lesions corroborated the current findings, particularly in lesion detection concerning size and phase variability. Marten S. van Leeuwen et al. identified 11 enhancement patterns, categorizing six as benign, three as malignant, and two as metastases and hemangiomas. Gualdi GF et al. presented 11 enhancement patterns, with four always indicative of benign disease and four of malignant disease. The rest were observed in both benign and malignant cases. The study showcased that 50% of metastatic lesions originated from colorectal carcinoma, 20% from pancreatic malignancy, and 10% each from stomach, ovary, and lung cancers. Gastrointestinal tract malignancies predominantly contributed to liver metastasis. Conclusion: Triphasic contrast-enhanced CT emerged as an optimal modality for characterizing focal liver lesions, revealing diverse enhancement patterns in different phases. Metastasis, particularly from colorectal carcinoma, dominated in the age group of 50-59 years. Hepatic arterial phase excelled in identifying hyper-vascular lesions, while the portal venous phase exhibited superior conspicuity for hypo-vascular lesions. This non-invasive tool, serving as the first line of differentiation between benign and malignant lesions, minimizes unnecessary biopsies for lesions like hemangiomas and certain infective pathologies with distinctive enhancing patterns. The study's findings align with previous research, emphasizing the robustness and clinical relevance of triphasic contrast-enhanced CT in liver lesion characterization. [ABSTRACT FROM AUTHOR]

This was a prospective, multicenter study designed to evaluate the utility of MDCT in the diagnosis of coronary artery disease (CAD) in patients scheduled for elective coronary angiography (CA) using different MDCT systems from different manufacturers. Twenty national sites prospectively enrolled 367 patients between July 2004 and June 2006. Computed tomography (CT) was performed using a standardized/optimized scan protocol for each type of MDCT system (> or =16 slices) and compared with quantitative CA performed within 2 weeks of MDCT. A total of 284 patients (81%) were studied by 16-slice MDCT systems, while 66 patients (19%) by 64-slice MDCT scanners. The primary analysis was on-site/off-site evaluation of the negative predictive value (NPV) on a per-patient basis. Secondary analyses included on-site evaluation on a per-artery and per-segment basis. On-site evaluation included 327 patients (CAD prevalence 58%). NPV, positive predictive value (PPV), sensitivity, specificity, and diagnostic accuracy (DA) were 0.91 (95% CI 0.85-0.95), 0.91 (95% CI 0.86-0.95), 0.94 (95% CI 0.89-0.97), 0.88 (95% CI 0.81-0.93), and 0.91 (95% CI 0.88-0.94), respectively. Off-site analysis included 295 patients (CAD prevalence 56%). NPV, PPV, sensitivity, specificity, and DA were 0.73 (95% CI 0.65-0.79), 0.93 (95% CI 0.87-0.97), 0.73 (95% CI 0.65-0.79), 0.93 (95% CI 0.87-0.97), and 0.82 (95% CI 0.77-0.86), respectively. The results of this study demonstrate the utility of MDCT in excluding significant CAD even when conducted by centers with varying degrees of expertise and using different MDCT machines. [ABSTRACT FROM AUTHOR]

Cardiovascular magnetic resonance (CMR) is a useful noninvasive technique for determining the presence of microvascular obstruction (MVO) and intramyocardial hemorrhage (IMH), frequently occurring in patients after reperfused myocardial infarction (MI). MVO, or the so-called no-reflow phenomenon, is associated with adverse ventricular remodeling and a poor prognosis during follow-up. Similarly, IMH is considered a severe damage after revascularization by percutaneous primary coronary intervention (PPCI) or fibrinolysis, which represents a worse prognosis. However, the pathophysiology of IMH is not fully understood and imaging modalities might help to better understand that phenomenon. While, during the past decade, several studies examined the distribution patterns of late gadolinium enhancement with different CMR sequences, the standardized CMR protocol for assessment of IMH is not yet well established. The aim of this review is to evaluate the available literature on this issue, with particular regard to CMR sequences. New techniques, such as positron emission tomography/magnetic resonance imaging (PET/MRI), could be useful tools to explore molecular mechanisms of the myocardial infarction healing process.

In more than 20% of all patients, the Crohn's disease presents before the age of 18years. The diagnosis and management of Crohn's disease in children has changed dramatically over the last decade, mainly due to increased awareness, availability of newer diagnostic modalities such as magnetic resonance imaging (MRI) and newer, more powerful treatments such as biologics. Imaging of the small bowel is needed for diagnosis, management, follow-up and also evaluation of the disease in terms of location, extent, activity and complications. We review all the methods (barium examinations, ultrasonography, computed tomography, MR, and computed tomography- positron emission tomography) commonly used for imaging the small bowel in paediatric patients with Crohn's disease analyzing the advantages and disadvantages of each modality, with particular emphasis on MR imaging.

Purpose: Alterations of the brain microstructure and metabolism have been identified in patients with neurofibromatosis type 1 (NF1). In this study, we analyzed the basal ganglia of NF1 subjects without cognitive delay throughout a combined approach with magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI) in order to better define the metabolic and microstructural characteristics of these regions and, furthermore, to verify if metabolic and microstructural abnormalities may be present in normally developed NF1 patients., Methods: A 3-T MRI with multivoxel MRS and DTI was performed in 14 NF1 patients and eight controls. N-acetyl-aspartate (NAA), choline (Cho), creatine (Cr) values and ratios, fractional anisotropy, and apparent diffusion coefficient (ADC) were calculated, for a total of four regions of interest (ROI) for each hemisphere., Results: NF1 patients, compared to healthy controls, showed (a) decreased NAA in all the four ROI, (b) increased Cho and decreased Cr in three of the four ROI, (c) decreased NAA/Cho ratio in three ROI, and (d) increased ADC in all the four ROI. A trend of increased ADC was present in three of the four ROI of NF1 patients with unidentified bright objects (UBOs) and younger than 18 years., Conclusion: These data confirm the presence of neuroaxonal damage with myelin disturbances in NF1 patients. We showed that metabolic and microstructural anomalies can be present in the same time in NF1 patients without developmental delay or cognitive deficits. Relations between brain anomalies, UBOs, and cognitive functions need further studies.

Atherosclerotic plaques can be responsible for life-threatening cardiovascular and cerebrovascular events. Some features of the plaque, such as a thin fibrous cap, large necrotic core, macrophage infiltration, neovascularization, and intraplaque hemorrhage, are associated with a major risk of such events and so their assessment is fundamental. Novel imaging techniques, each one with its own strength and drawbacks, can help in the evaluation and quantification of atherosclerosis. An analysis of the recent literature was carried out. The different techniques were compared by evaluating the accuracy of each one in the detection and assessment of the atherosclerotic plaque's features named above., (© 2012 The Authors. Therapeutic Apheresis and Dialysis © 2012 International Society for Apheresis.)

Background: Evidence-based criteria in the therapeutic choice for sigmoid acute diverticulitis (AD) are lacking. It is necessary to differentiate an acute episode of diverticular disease, not complicated (NCAD) and complicated (CAD) because these stages of diverticular disease needs different approach., Methods: In a prospective study on 377 consecutive patients admitted for AD, 265 had NCAD and 112 CAD diagnosed with CT scan. Thirty-six of 265 with NCAD were operated on due to two or more previous episodes of AD. On 188 patients with NCAD followed-up, 35 had further episodes of NCAD and 2 had CAD. On 112 CAD patients, 61 had Hinchey I and were submitted to colonic resection. Twenty-three of 24 patients with Hinchey II were treated with percutaneous drainage. All Hinchey II patients were operated on. All the 13 patients with Hinchey III and IV had emergency surgery., Results: We had no mortality and respectively 9.8% and 30% morbidity in Hinchey I and II patients. In Hinchey II patients percutaneous drainage was successful in 21 on 23 (91.3%). In 13 Hinchey III and IV patients the mortality rate was 25%. The comparison of CT findings and pathological results showed a sensitivity of 100% and predictive positive value of respectively 94.4, 96.7, 100 and 100% for NCAD, Hinchey I, Hinchey II and Hinchey III-IV., Conclusions: The therapeutic approach of diverticular disease needs to differentiate among an acute episode, NCAD and CAD. Evidence-based therapeutic choices can be reached only by homogeneous diagnostic criteria obtained by CT scan.

Last years technological developments in imaging field have made a substantial contribution to diagnosis and staging of rectal cancer. Endorectal ultrasound and MRI with endorectal coil are very useful in rectal cancer initial staging thanks to their ability to distinguish between the rectal wall layers. Major ultrasound limitations are presence of inflammations, desmoplastic reaction and small field of view which limits evaluation of perirectal invasion. MRI with phased-array coils, instead, allows depiction of mesorectum and to assess the distance between tumor and mesorectal fascia. Unfortunately CT shows low accuracy compared to MRI in local staging because it fails to distinguish the rectal wall layers. The criterion used in assessing nodal involvement remains unfortunately still the dimensional one even if new contrast media based on nano-iron particles look promising in this regard On reassessment after chemo-radiotherapy treatment, MRI proved to be a very accurate tool thanks to its ability to detect tumor downstaging, disappearance of mesorectal fascia infiltration or even to show a complete response. The presence of recurrence can be studied by contrast enhanced perfusion-MRI or with good accuracy using PET which, however, presents major technical limitations at present.

Background: Unenhanced computed tomography (CT) is the imaging technique used in acute stroke. In some cases it is unable to detect damage even 24-48 h after symptom onset. The aim of our work was to evaluate the diagnostic value of diffusion-weighted imaging (DWI) in the post-acute phase of cerebral ischemia in patients in whom CT did not yield a definitive diagnosis., Methods: We retrospectively evaluated DWI findings in 214 patients, out of a series of 1,680 patients admitted to our hospital following the acute onset of focal neurological symptoms, in whom non-contrast CT, performed within 30 h of symptom onset, was normal (123), incongruous, i.e. a marked hypodensity indicative of an old infarct or a slight hypodensity not consistent with the clinical findings (66), or leukoaraiotic, i.e. diffuse chronic hypodensities in the periventricular white matter (25)., Results: DWI showed signs of recent brain ischemia in 125/214 (58%) patients: 64/123 (52%) with a normal CT, 41/66 (62%) with an incongruous CT, and 20/25 (80%) with leukoaraiosis (p=0.027). Multiple lesions were detected in 16/125 (16%) patients, while single lesions were

The primary role of imaging in identification as well as in characterization adrenal lesions has been demonstrated by several studies. The recent technologic progress has allowed to identify adrenal lesions even when they are very small, with a consequent conspicuous increase of the frequency of incidentalomas. Computed Tomography, Magnetic Resonance and Nuclear Medicine are routinely used to evaluate adrenal glands and their pathologic conditions. The aim of this article is to show how the imaging is employed to assess adrenal masses, with special regard to the contribution given by Computed Tomography (CT) and Magnetic Resonance (MR) imaging to the differential diagnosis between benignant and malignant lesions.

The purpose of Radiologic Unit in Emergency is to reach diagnostic and therapeutic effectiveness in the best way and in less time possible. The Portable Ultrasound Device is an instrument necessary in Emergency Room and in ambulance/helicopter to evaluate the evidence of endoperitoneal bleeding. The CT is the radiologic methodic more fast that permits a complete evaluation of all body segments in traumatized patient in the famous "golden hour" after the trauma, therefore it would be placed in Emergency Area. The multislice CT brought to a reduction of morbidity and mortality, thanks to a quick acquisition, to a thin collimation, to a more spatial resolution and to an optimal vessel opacization, determining a saving of hospital global costs, therefore a reduction of percentage of not necessaries operations and permitting a more rapid diagnosis, obtaining a considerable reduction of waiting in Trauma Emergency Room with more rapid and aimed therapies and a consequent costs reduction. To satisfy a so wide question of radiologic exams necessaries devices are informatic systems completely connected between Radiology department and other departments. Main advantages of MR in Emergency are the use of non ionising radiations, the possibility to effect diffusion and perfusion studies and to evaluate spinal cord damage. Reduction of time of patient preparation and times of acquisition and elaboration of imagines by modern and performant devices is basic to make more rapid therapeutic decisions.

Pancreatitis is a flogistic disease, caused by activation and digestion of pancreas by its enzymes. Diagnosis is based on integrated evaluation of clinical and laboratoristic data and morphological imaging. To evaluate the severity of pancreatitis there is a clinical classification in interstitial--mild pancreatitis and severe--necrotic one. The evaluation of severity is basic, because it is strictly correlated to the prognosis of the patient. CT has revealed the best method for diagnosis, staging and for evaluate the complications and follow-up and in some cases it is useful for therapeutic change.The abdomen X-Ray in orthostatism is performed in every situation suspected for acute abdominal disease, also if aspecific; the ultrasound can be used as first instance method in patient with clinical suspect of acute pancreatitis; the MR has actually a secondary role for the diagnosis, with only except for dubious cases to exclude primitive tumor of pancreas and pancreatic shock, but it represents, instead, first instance method in patients with adverse reaction to contrast medium. The CPRE has, like angiography, a selective indication.

The clinic diagnosis of degenerative lumbar intervertebral instability is a controversial topic and have not yet been clarified clinical criteria for to define this condition with accuracy. Although the lumbar pain is the most common symptom in patients who have lumbar intervertebral instability its clinical presentation is not specific; moreover in patients with lumbar pain there are no agreed signs and symptoms that can be truly attributable to instability. Despite better imaging techniques of testing spinal instability there is not a clear relations between radiologic signs of instability and clinical symptoms. It is, however, still far from unanimous definition of degenerative lumbar intervertebral instability accepted from all specialists involved in diagnosis and treatment of this condition; however, seem there is most agree about suspected vertebral instability. Nevertheless this unresolved topic, it is possible to state that imaging play an increasing role in diagnosis and management of patients with suspected instability. The aim of this study is to investigate the different imaging modalities most indicated in diagnosis if vertebral instability and whether degenerative change can be associated with lower back pain.

Acute pancreatitis is one of the more commonly encountered etiologies in the emergency setting. While in the majority of cases it is a self-limiting disease which responds rapidly to conservative management, in some cases acute pancreatitis may present with a more pronounced, sometimes dramatic, clinical picture and requires immediate medical care to avoid fatal complication. In this context, imaging plays a significant role because it enables identification of the development of the disease and local/systemic complications. The purpose of this article is to offer an overview of the disease and a spectrum of imaging findings in patients with acute pancreatitis, emphasizing the role of ultrasound, computed tomography, and magnetic resonance imaging according to the appropriate clinical context and advantages and limitations of each imaging modality are examined.

Objective: The objective of our study was to evaluate the sensitivity and specificity of endorectal MRI combined with dynamic contrast-enhanced MRI to detect local recurrence after radical prostatectomy., Materials and Methods: A total of 51 patients who had undergone radical prostatectomy for prostatic adenocarcinoma 10 months to 6 years before underwent a combined endorectal coil MRI and dynamic gadolinium-enhanced MRI before endorectal sonographically guided biopsy of the prostatic fossa. The MRI combined with MR dynamic imaging results were correlated with the presence of recurrence defined as a positive biopsy result or reduction in prostate-specific antigen level after radiation therapy., Results: Overall data of 46 (25 recurred, 21 nonrecurred) out of 51 evaluated patients were analyzed. All recurrences showed signal enhancement after gadolinium administration and, in particular, 22 of 24 patients (91%) showed rapid and early signal enhancement. The overall sensitivity and specificity of MR dynamic imaging was higher compared with MRI alone (88%, [95% CI] 69-98% and 100%, 84-100% compared with 48%, 28-69% and 52%, 30-74%). MRI combined with dynamic imaging allowed better identification of recurrences compared with MRI alone (McNemar test: chi-square(1) = 16.67; p = < 0.0001)., Conclusion: MRI combined with dynamic contrast-enhanced MRI showed a higher sensitivity and specificity compared with MRI alone in detecting local recurrences after radical prostatectomy.

New technologies in these years has taken to a spread and to a growth of the CT application with an increase of patients and population exposure. In clinical practice some technical devices can be used to reduce the exposure dose of multidetector CT that allows radiologist to answer the clinical question with less damage to the patient. The radiologist remains however the guarantor of the ionizing radiation exposition and he has to consider also the opportunity to use other methodics (MR, US) to answer some questions. The radiologist has the role to evaluate the clinical indication to the exam demanded from other doctor and has the responsibility for exam management and for progressive radiologic course, controls and follow-up.

Aim: The diagnosis of acute coronary syndrome (ACS), non-ST-elevation myocardial infarction and unstable angina in the emergency department (ED) remains a challenge. The aim of our study was to investigate quality and the diagnostic accuracy of 16-MDCT coronary angiography, detecting coronary artery lesions in patients with suspected ACS presented in ED., Materials and Methods: We studied with 16-MDCT (Sensation 16, Siemens, Forchleim, Germania) and coronary angiography 37 patients with the following inclusion criteria: chest pain compatible with myocardial ischemia, normal or no-diagnostic ECG changes and initial concentrations of serum troponin-I < or =1 ng/ml. The 16-MDCT was performed with ECG-gated technique after the intravenous administration of 90-100 ml of iodinated contrast material followed by a saline bolus. The scan parameters were: 120 kV, 650-720 mAs, 16 x 0.75mm collimation, 0.42s rotation time, 3 mm (pitch 0.25) feed/rot, B30f kernel. We evaluated for each patient: image quality and different artefacts, plaques identification and characterization., Results: The evaluation of the image quality was based on a total of 453 segments, of which 415 segments (92.2%) were considered to have diagnostic image quality. MDCT correctly detected 15 patients with at least 1 stenosis >50% and correctly ruled out significant coronary artery disease in 19 patients with 1 FP and 2 FN: sensitivity 88%, specificity 95%, PPV 94%, NPV 90%. The plaques were hard in 6 cases, mixt in 16 cases and soft in 14 cases, respectively., Conclusions: Our results point-out that 16-MDCT in ED has the real ability to detect and rule out significant coronary stenoses in patients with ACS.

Purpose: To establish the additional value of 3D magnetic resonance spectroscopy (3D-MRS) imaging to endorectal MR imaging in the diagnosis of prostrate cancer in the peripheral zone., Materials and Methods: MR imaging and MRS imaging were performed in 79 patients with suspicion of prostate cancer on the basis of digital rectal exploration, transrectal ultrasound and PSA level. All the examinations were performed with 1.5 T MR scan using an endorectal coil (transverse and coronal FSE T2-weighted sequences, axial SE T1-weighted and PRESS 3D CSI). MR examinations have been evaluated by two Radiologists blind of the clinical data in a "per patients" analysis. MR imaging and MRS imaging findings were compared with the result of histological data from radical prostatectomy in 53 patients and biopsy in 17 patients., Results: Nine patients (11.4%) were excluded because of serious artefacts in the MR spectrum. The reported values of sensitivity, specificity, PPV and NPV for MR imaging alone were respectively 84%, 50%, 76% and 63% (LR+ 1.7; LR- 0.3). Instead the reported values of sensitivity, specificity, PPV and NPV for the combination of MR imaging to MRS imaging were respectively 89%, 79%, 89% and 79% (LR+ 4.28; LR- 0.14). We found an incremental benefit of MRS imaging to MR imaging for tumour diagnosis although these results did not show statistically significant differences., Conclusions: The MRS imaging improves the accuracy of the endorectal MR imaging in the diagnosis of prostate cancer.

The central nervous system inflammatory disease can be due to any kind of infective agent (bacterial viral, fungal and parasitic), but entails also multiple sclerosis, a primary demyelinating disease in which the causal agent is unknown. MR imaging is, in most often, the procedure of choice, due to her multiplanar and multiparametric imaging, and to her better contrast resolution. The post-contrast imaging with double dose of gadolinium and late sequences enable visualisation of smallest pathologic foci or slightest blood-brain barrier alterations, with a sensibility very higher than post-contrast CT scan. In addition, RM provide to many functional informations, by means of diffusion, perfusion and spectroscopy studies, Bold technique for cortical activation studies and Fiber Tracking technique, in order to demonstrate pathologic modification earlier than they are evident on morphologic imaging. Functional imaging is also employed to monitor response to treatment and damage reversibility.

Gastroduodenal obstruction is a preterminal event in patients with advanced malignancies of the stomach, pancreas and duodenum. Surgical gastrojejunostomy has been considered the traditional palliative treatment. The use of metallic stents is intended not to be curative but to provide nonsurgical palliation for the symptoms of obstruction. The advantages of this technique are the minor invasivity, the decrease in morbidity and mortality respect the surgical approach, the patient that can be discharged the day of or the day after the procedure and the better life expectation.

An abused child can present with every lesion known to medicine, but some of these lesions can be specific of child abuse. The most frequent skeletal lesions are that of the long bones, of the head and the chest. Head damages are responsible for 80% of the dead in abused child. These kind of lesions are very important because they can produce important neurological deficits. Most frequent are extraxial bleeding and intraparenchimal lesions. Abdominal damages are the second cause of dead in the abused child. They can be asymptomatic and so they can be misdiagnosed. They are not so frequent but if they are present, they are letal. Conventional radiology, CT and MRI are very important in the management of child abuse because they allow to reveal multiorgan damages which, in some instances, can be specific of a child abuse.

Enteroclysis has been suggested as the technique of choice for the evaluation of Crohn disease of the small intestine. Adequate distention of the entire small bowel with barium suspension allows the radiologic demonstration of mucosal abnormalities and provides functional information by defining distensibility or fixation of the small bowel loops. The principal disadvantage of conventional enteroclysis is the limited indirect information on the state of the bowel wall and extramural extension of Crohn disease, and its effectiveness may be hindered owing to overlapping bowel loops. Moreover, the radiation dose administered to patients, mostly at a young age, should be considered. Magnetic resonance (MR) enteroclysis is an emerging technique for small bowel imaging and was introduced to overcome the limitations of conventional enteroclysis and MR cross-sectional imaging by combining the advantages of both into one technique. MR enteroclysis has the potential to change how the small bowel is assessed because of the functional information, soft tissue contrast, direct multiplanar imaging capabilities, and lack of ionizing radiation.

The results of recent studies of magnetic resonance imaging (MRI) combined with three-dimensional magnetic resonance spectroscopic imaging (3D-MRSI) demonstrate that the MRI/3D-MRSI exam is a unique method by which to noninvasively study the cellular metabolism and anatomy of the prostate. 3D-MRSI is emerging as the most specificity tool for non-invasive evaluation of the prostate cancer. The results of current MRI/3D-MRSI studies also provide evidence that the magnitude of metabolic changes in regions of cancer before therapy, as well as the extent of the time course of metabolic changes after therapy, may improve our understanding of cancer aggressiveness. Assessment of cancer spread outside the prostate can be significantly improved by combining MRI findings with estimates of metabolic abnormalities provided by 3D-MRSI. Clinically, combined MRI/3D-MRSI has already demonstrated a potential for improved diagnosis, staging, and treatment planning for patients with prostate cancer. This article reviewed the value of 3D-MRS imaging for the diagnosis, localization, staging, aggressiveness, and treatment planning of prostate cancer.

Purpose: The aim of this study was to identify and classify the ultrasonographic and computed tomography (CT) signs of simple and complicated acute cholecystitis and to define the correct diagnostic protocol., Materials and Methods: We retrospectively reviewed 35 patients (23 men and 12 women; mean age 66.6 years) presenting with acute cholecystitis who were assessed by emergency ultrasonography (US) (30/35 cases) and spiral CT (12/35 cases); all patients underwent emergency surgery. The US signs were analysed and classified as major criteria (wall thickening and stratification, distension, Murphy's sign), minor criteria (bile stones, sludge, and biliary tract dilatation), and complication signs (gas collections, aerobilia, fluid collection, difficult or missed identification of the gallbladder). Imaging results were compared with histological findings (gold standard), and accuracy, sensitivity, specificity, and positive and negative predictive values (PPVs and NPVs) were assessed for each modality. Concordance between the US and CT findings was also evaluated for cases undergoing both examinations; additional findings provided by one or the other modality were also assessed., Results: US had an accuracy of 66.6%, a sensitivity of 37.5%, a specificity of 70%, a PPV of 100%, and an NPV of 58.3%. CT had 100% accuracy, sensitivity, and specificity. Concordance between US and CT was observed for diagnosis of complications, but CT provided additional findings in all cases. The majority of complicated cases undergoing US examination (68.7%) revealed more than two major criteria and one minor criterion or at least one sign of complication., Conclusions: If more than two major signs associated with one minor sign or at least one sign of complication are present at US, CT is mandatory to recognise and thoroughly evaluate the type of complication and indicate appropriate treatment.

Virtual endoscopy is a new method for studying the colon; it consists in acquisition of CT and MR images and to elaborate them with a workstation, to create endoluminal vision as like as traditional colonscopy, permitting the complete exploration of colonic lumen, also with stenotic tumors. The analysis of the differences between CT and MR colography shows like these two techniques present both advantages and disadvantages, such as the impossibility to perform MR in patients with pace-maker or in claustrophobic patients and the impossibility to perform CT with iodated agents in patients with renal failure or with a story of adverse reactions. The increased use of these techniques is due to the high sensitivity of last-generation CT and MR machine, to the increased spatial resolution, to specific softwares for digital cleaning of colon, to the introduction of high-end workstations and to the possibility of computed assisted diagnosis (CAD). So, it is desiderable that the increasing spread of multidetector CT devices and the future technical innovations, should have the effect to increase culture and experience in various diagnostic centers about CT-colography, making possible the spreading of virtual endoscopy as a screening tool.

Purpose: One the main reasons for the limited use of MRI in the evaluation of aortic dissection in emergency conditions is its long execution time. The authors report their experience regarding a new MRI sequence that reduces execution time and avoids the use of contrast medium., Materials and Methods: Eighteen haemodynamically stable patients with suspected (16 cases, 3 with confirmed diagnosis of aneurysm) or known aortic dissection (2 cases) underwent in emergency conditions 1.5T MRI with Steady-State sequence (Fast Imaging Employing Steady-State Acquisition: GRE 2D; TR 3.5, TE 1.6; Flip Angle 45, bandwidth 125, matrix 224x224, NEX 1, acquisition time per slice 7 s, thickness 6-8 mm, FOV 38; 2D-GE breath-hold sequence requiring cardiac triggering). The results obtained were compared in terms of diagnostic accuracy and execution time with those of classical MRI examination (black blood T1, FSE T2 and 3D MR-angiography) or multislice CT., Results: The diagnostic accuracy of MRI, both with Steady-State sequence and the ''classical'' technique, and multislice CT in the diagnosis of dissection or aneurysm is equal (100%), whereas execution time is 6, 25 and 6 minutes, respectively. Multislice CT proved to be more accurate than Steady-State MRI in evaluating the renal parenchyma and the extension of the dissection to the renal arteries., Conclusions: The Steady-State MRI sequence provides a diagnosis of aortic dissection or aneurysmal dilatation in a short time and may represent a valuable alternative to CT in emergency settings, especially in patients with reported contraindications to iodinated contrast media.

Median sternotomy is the surgical technique of chosen for cardiac surgery. Although the complications after median sternotomy are not so frequent, these are associated to elevated mortality. The complications can interest the presternal compartment, the sternal compartment or the retrosternal compartment. Even if the clinical diagnosis of infection is not difficult for the clinician, it is nearly impossible to establish the depth of the infection. Multislice CT, thanks to the possibility to obtain thin layers and three-dimensional multiplanar reconstructions and Volume Rendering, turns out extremely useful for being able to demonstrate the extension and the depth of the infection. Of fundamental importance it is the elaboration of the images, executed on workstation, with which multiplanar reformatted and Volume Rendering images are obtained. The CT turns out useful moreover like guide for the execution of interventional procedures such as aspiration of material for bacteriological characterization or eventual positioning of a catheter for abscess drainage. The Magnetic Resonance, thanks to its high resolution of contrast and to its multiplanarity, finds one of its elective applications in the study of the flogistic and neoplastic processes of the soft tissues. A great limit of the MR is the possible generation of artifacts due to sternal suture.

Purpose: To establish the additional value of MR Spectroscopy (3D CSI MRS Three-dimensional Chemical Shift Imaging Magnetic Resonance Spectroscopy) to endorectal MR in the diagnosis and grading of prostate cancer., Materials and Methods: MR and 3D CSI MR spectroscopy were performed in 53 patients with suspicion of prostate cancer on the basis of rectal exploration and/or transrectal ultrasound and/or the PSA levels. All the examinations were performed with a 1.5 T imager using an endorectal coil. We acquired axial and coronal T2-weighted FSE sequences, axial T1-weighted SE sequences and PRESS 3D CSI (Point Resolved Spectroscopy 3D Chemical Shift Imaging) sequences localized on the axial T2 images so as to include the prostatic gland while excluding the periprostatic fat. The MR examinations were evaluated by two radiologists unaware of the clinical data, transrectal ultrasound findings, PSA levels and histological findings. The MR and 3D CSI MRS findings were compared with the biopsy findings in 22 cases and with material obtained from laparoscopic prostatectomy in 31 cases., Results: The histological examination revealed adenocarcinoma in 37 cases, prostatitis in 2 cases and no alterations in the remaining 14 cases. The morphologic MR scan showed a sensitivity of 76%, a specificity of 56%, an accuracy of 70%, a PPV of 80% and a NPV of 50%. By combining MR and 3D CSI MRS we obtained a sensitivity of 95%, a specificity of 81%, an accuracy of 91%, a PPV of 92% and a NPV of 87%. Elevated choline concentrations were found both in tumours with a low Gleason score (18 cases) and in those with a high Gleason score (19 cases); instead we found markedly reduced (n=9) or absent (n=4) citrate only in the tumours with a high Gleason score, while we found normal citrate levels in the 18 tumours with a low Gleason score., Conclusions: The 3D CSI MRS improved the reliability of endorectal MR in the diagnosis and characterisation of prostatic cancer. Moreover, the 3D CSI MRS findings demonstrated a linear correlation with tumour grade.

Alzheimer disease (AD), the most common cause of dementia in the elderly, is a progressive neurodegenerative disorder, associated with deterioration in cognition and behaviour. With the availability of newer drugs for symptoms treatments there is a general agreement to the need of an early diagnosis and an the development of new sensitive tools, to identify and/or monitor early cerebral changes, suggestive for AD. CT and MRI are recommended for routine evaluation, in order to exclude treatable causes of dementia and to exactly evaluate the degree of cerebral atrophy and the presence of parenchymal signal abnormalities. Functional imaging, including PET, SPECT and functional MR techniques, are able to investigate physiological cerebral function, such as blood perfusion, metabolism, activation, molecular composition and water diffusibility, and have the potential to detect subtle pathological changes earlier during course of disease. MRI can provide both an accurate morphological assessment and a functional evaluation. Further investigations are needed to precisely define which will be the role of the different MR techniques. Most likely an exhaustive evaluation of AD will include information obtained by conventional and functional imaging, combined with clinical, laboratory and genetic findings.

The cancer is a problem that plagues all the ages but the greater part of the malignant tumors hits the old persons. The more elevated incidence sites of primary tumor in geriatrical age are the prostate, the lung and the colon-rectum in the men and the breast, the colon-rectum, the lung and the stomach in the women. The imaging has made steps of giant in the last few decades, with the introduction of new equipment and methodical news so as to assure everybody early and accurated diagnosis. For the lung carcinoma great advantages have been bring to us with the introduction of CT-PET and the multislice CT, that has concurred the execution of virtual bronchoscopy. The virtual endoscopy has been applied with happening also in the screening of the carcinoma of colon-rectum, executed through CT or MR. New MR technologies have allowed perform spectroscopic studies in such organs as prostate and breast, bringing the biochemical diagnosis beyond that morphologic. The MR then turns out fundamental in the appraisal of the Patient with bone metastases thanks also to the new whole body examinations. Finally the recent technology has allowed the execution of multiorgan CT screening bringing in this way new possibilities but also new questions.

Next to the knee, the shoulder is the most common joint to be referred for MRI. Excellent soft tissue contrast and multiplanar acquisition provide optimal assessment of muscle, tendons, hyaline and fibrous cartilage, joint capsule, fat, bursae and bone marrow. In this article the most common indications for shoulder MRI are reviewed and discussed, but we focused primarily on the rotator cuff syndrome and shoulder instability. Correct diagnosis requires the use of appropriate pulse sequences and imaging planes, proper patient positioning, and a satisfactory surface coil. Moreover, technical improvements continuously augment the ability of MRI to study the shoulder; for example Magnetic Resonance arthrography is superior to the other imaging techniques in evaluation of glenohumeral joint. This interdependence between technical development in MRI and clinical advance in shoulder therapy ensures that MRI will continue to play an important role in the routine management of patients with shoulder disease.

The diagnostic ability of Magnetic Resonance Colonography (MRC) in detecting colonic endoluminal masses was compared with that of conventional colonoscopy (CC) and related to the findings from histologic examination. In seventy consecutive patients MRC achieved a diagnostic accuracy similar to CC. Therefore MRC could be useful in screening patients at high risk for colonic cancer. However every patient with MRC-detected endoluminal lesion must undergo CC for histologic diagnosis.

Neuroendocrine tumors (NET) of the pancreas are distinguished in functional (85%) and non functional (15%) in relation to the production and release of the hormone produced. Functional tumors show early, because the neoplasm release the hormone produced when they are still small. Non functional tumors show late when the tumor grows. The localization and the evaluation of the extensive of these tumors has come fundamentally important both in correct presurgical detection and also in the diagnosis of metastases which excluded surgery. Also, as the survival of 20% of the patients with metastases is only five years, the use of non-invasive imaging techniques is very important for the evaluation of results of the various therapies (chemotherapy, interferon, somatostatin). Recent studies have shown that in patients with Zollinger-Ellison syndrome, SRS is the most sensitive non invasive method in localizing primitive tumors and metastases. The accuracy of this technique has not yet been provided in the study of tumors like insulinomas which do not have a high percentage of somatostatine receptors on their cell membranes. The sensitivity obtained in recent studies on a large number of patient and the low cost, lower than all the other imaging technique in use today, surely make SRS the first choice in the study of NET. Where SRS is negative and surgery is possible, Spiral CT or better still MRI is the best tool to check the results of chemotherapy in patients with hepatic metastases (already detected by SRS), because it is easier to compare the changes in size and morphology of metastases.

Background & Aims: The most effective prophylaxis for colorectal cancer is endoscopic polypectomy. Prompted by the disadvantages of conventional colonoscopy (CC), we assessed the diagnostic ability of a promising alternative technique for detecting endoluminal masses: magnetic resonance colonography (MRC)., Methods: Seventy consecutive patients referred for CC underwent preliminary MRC. The diagnostic ability of this technique in detecting colonic endoluminal lesions was determined, compared with that of CC, and related to the findings from histologic examination., Results: In detecting endoluminal lesions, MRC achieved a diagnostic accuracy similar to CC (sensitivity, 96%; specificity, 93%; positive predictive value, 98%; and negative predictive value, 87.5%)., Conclusions: MRC could be useful in screening programs of patients at high risk for colon cancer. Patients with MRC-detected endoluminal lesions must undergo CC for histologic diagnosis.