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R Passariello

Publications and source records attributed to R Passariello.

At least 73 records · Page 4Linked to original sources
PubMed1997

Cost containment and diffusion of MRI: oil and water?. The situation in Europe.

Investments in diagnostic imaging in European countries range between 2.2 and 5.4 % of gross national product, a figure which, in view of new imaging modalities and increased radiological density, is considered to be wholly inadequate. Despite the fact that radiological examinations contribute more than laboratory tests and other diagnostic modalities to the final clinical diagnosis, and that MR is of increasing clinical relevance, economic constraints mean that the number of new MRI installations in Europe is decreasing relative to the situation elsewhere. The present article discusses the current state of radiological imaging in Europe with particular emphasis on present and expected future trends in MRI.

Cost Control↗
PubMed1997

MR cholangiography (MRC) in the evaluation of CBD stones before laparoscopic cholecystectomy.

BACKGROUND: The aim of our work was to evaluate the predictive value of MR cholangiography (MRC) in detecting CBD stones before laparoscopic surgical treatment. METHODS: MRC was performed as a unique preoperative imaging modality in 45 selected patients (16 male; 29 female; age range: 28-72; mean age: 54.4) before laparoscopic cholecystectomy. MRC imaging was obtained with a 3D Turbo Spin-Echo sequence (TR = 3000 ms, TE = 700 ms, Echo Train Length--128) with an acquisition time of 5 min 48 s. Diagnostic confirmation was obtained in all the cases at i.o. cholangiography. When a stone was detected it was removed by transcystic or transcholedochal approach. RESULTS: Eighteen of the 45 patients (40%) had CBD stones. MRC correctly evaluated 16 out of 18 stones, with a resulting sensitivity of 88.9%, specificity 100%, positive predictive value 100%, negative predictive value 90%, and accuracy 95.6%. CONCLUSIONS: Despite the good results of MRC, it cannot be proposed as a screening technique to be performed in all patients submitted to laparoscopic cholecystectomy due to high cost and the limited amount of MR equipment. In conclusion, only selected patients should be submitted to MRC before laparoscopic cholecystectomy.

Adult↗
PubMed1997

Magnetic resonance-cholangiopancreatography in the diagnosis of biliopancreatic diseases.

BACKGROUND: Magnetic resonance cholangiopancreatography (MRCP) is a new, noninvasive imaging technique for the visualization of the biliary ducts with cholangiographic images similar to those obtained with endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography. No contrast medium injection is used. The aim of this study was to assess the feasibility of MRCP versus ERCP in the diagnosis of biliary tract and pancreatic diseases. PATIENTS AND METHODS: One hundred and thirty-six patients were submitted to MRCP. They were referred to MR study according to four inclusion criteria: (1) evidence or suspicion of choledocholithiasis, (2) benign or malignant bile ducts stenosis, (3) follow-up of patients submitted to biliary-enteric anastomosis, and (4) chronic pancreatitis with Wirsung duct dilatation. The MRCP was performed with a 0.5T superconducting magnet (Philips Gyroscan T5). When neoplastic disease was detected, additional images on axial planes were acquired. MRCP allowed images of diagnostic value to be obtained in all the cases. RESULTS: In choledocholithiasis, MRCP showed 91.6% sensitivity, 100% specificity, and overall diagnostic accuracy 96.8%. Of 48 patients with stenotic lesions, 16 were correctly characterized as benign and 30 as malignant. Two cases of focal chronic pancreatitis were misdiagnosed as pancreatic head carcinoma. In the patients submitted to biliary-enteric anastomosis, MCRP was able to detect the dilatation of the intrahepatic ducts, the stenosis, and associated stones in all 8 positive cases. In the remaining 7 patients with mild signs of cholangitis, MCRP showed irregular aspects of the biliary tree in the main ducts. In the 11 patients with chronic pancreatitis, MCRP was able to depict the dilated Wirsung duct and the stenotic tract, although the fine details of the secondary ducts were not evaluated due to the low spatial resolution as compared with conventional films. CONCLUSIONS: MRCP can be considered a technique able to completely replace diagnostic ERCP. Further studies are necessary for a better evaluation of the potential advantages and disadvantages of this technique.

Adult↗
PubMed1997

Role of MR venography in the evaluation of deep venous thrombosis.

PURPOSE: MR venography has been recommended for the evaluation of deep venous thrombosis. The purpose of our study was to determine the role of MR venography, in particular at the level of the pelvis where other diagnostic modalities show major limitations. MATERIALS AND METHODS: Forty-three patients with clinical suspicion of deep venous thrombosis were examined by means of pelvic MR venography. In all cases, a 2D-TOF sequence was used with cranial arterial presaturation. In selected cases, i.e. when a small intraluminal filling defect was present, a cine-PC sequence was used in addition in order to exclude the presence of a pulsatility artifact as causing the filling defect. In all cases, contrast venography was also performed and considered to be the standard of reference. RESULTS: MR venography showed 26 patients to be positive for deep venous thrombosis at the pelvic level. These positive results were correct in 25 cases. The analysis of the results provided values of sensitivity and specificity of respectively 100% and 94%, with an overall accuracy of 97.6%. CONCLUSIONS: Our results indicate that MR can provide highly accurate images, similar to those of contrast venography, in a noninvasive fashion. It is particularly useful in the pelvic region where the limitations of other imaging modalities are more evident.

Contrast Media↗
PubMed1997

MR cholangiography in the examination of patients with biliary-enteric anastomoses.

OBJECTIVE: The aim of our study was to determine the role of MR cholangiography in the noninvasive examination of patients with biliary-enteric anastomoses. SUBJECTS AND METHODS: Twenty-four patients (nine men and 15 women; mean age, 68.9 years old) with biliary-enteric anastomoses underwent MR cholangiography. We used a fat-suppressed three-dimensional turbo spin-echo sequence (3000/700 [TR/TE]; echo train length, 128) with no breath-hold, optimized with a 0.5-T magnet. Imaging studies were performed because of scheduled follow-up (five patients), persistent jaundice (six patients), cholangitis and abnormal liver function (eight patients), and a combination of transient jaundice, epigastric pain, and abnormal liver function (five patients). RESULTS: Image quality was graded from optimal to good in 21 (88%) of 24 cases and poor in three (13%) of 24 cases. The degree of bile duct dilatation was correctly assessed, with complete agreement between the two observers in all cases. MR cholangiography correctly showed bile duct irregularities in six of the eight patients with cholangitis (kappa = .59), anastomotic strictures in all 19 patients with strictures (kappa = .86), and 3- to 15-mm stones in nine of 10 patients (kappa = .95). A slight overestimation of the strictures occurred in four of the 19 cases with strictures. CONCLUSION: MR cholangiography is a reliable imaging technique for the examination of patients with biliary-enteric anastomoses.

Aged↗
PubMed1997

[Combined conventional magnetic resonance, magnetic resonance angiography, and magnetic resonance cholangiopancreatography in the diagnosis and staging of pancreatic carcinoma].

PURPOSE: This study was aimed to integrating MR CholangioPancreatography (MRCP) and MR Angiography (MRA) to conventional MR images in the diagnosis and resectability assessment of pancreatic adenocarcinoma. MATERIAL AND METHODS: Twenty-three consecutive patients with pancreatic adenocarcinoma (16 in the head and 7 in the body-tail region) were examined with MR. Conventional MR, 3D MRCP and venous and arterial MRA images were acquired to assess biliary and vascular involvement. Acquisition time never exceeded 40-45 minutes. The images were independently studied by two radiologists and the final reading was decided upon consensus among readers. Sixteen patients underwent surgery. RESULTS: The diagnosis was confirmed at surgery in 16 patients and at percutaneous biopsy in 7. Interreader agreement was considered high, with .83 interobserver variability. Pancreatic adenocarcinoma was found in all patients examined. Unresectability because of vascular involvement was correctly assessed in all patients but 1. Biliary obstruction was demonstrated in 13 patients, involving the biliary and pancreatic ducts in 9 and the biliary ducts only in 4. CONCLUSION: Technical advances now permit the extensive application of MRI to the study of abdominal conditions. The combination of MRI, MRCP and MRA can provide most of the information needed for the diagnosis and resectability assessment of pancreatic adenocarcinoma, which can otherwise be obtained only performing three different exams.

Adenocarcinoma↗
PubMed1997

[Role of magnetic resonance in the evaluation of the normal and osteochondrosis hip in early and late childhood].

INTRODUCTION: Despite MR potentials, few studies investigate the features of normal hips and of hip osteochondrosis in early and late childhood. We report our personal experience with MRI of hip osteochondrosis in pediatric patients. MATERIAL AND METHODS: MR images were obtained with total body MR equipment at medium and high fields. The normal hips were studied in children aged 34 months to 6 years with abdominal-urinary tract disorders and in 9 patients of the same age with unilateral Perthes disease. Hip osteochondrosis was studied in 6 children with Catteral's type III and IV and in 3 with type I and II disease. General anesthesia was never necessary to perform MRI. RESULTS: MRI exactly defined the cephalic anatomic profiles of normal hips which are not depicted with conventional radiography before the femoral head cartilage ossifies completely. MR contrast resolution was very high in depicting the maturation of the epiphyseal nucleus and its exact site in the cartilagineous epiphyseal hemisphere proximal to the femur. The analysis of MR morphological and structural changes permitted to correlate MR findings with the histopathologic features described in the literature. In addition, MRI of childhood hip osteochondrosis showed maked structural changes of the epiphyseal nucleus which are usually missed with conventional radiography. MRI permits early location of the abnormal area and the recognition of growing disk abnormalities; it also shows the whole cephalic cartilage and the changes of the epiphyseal nucleus evolution, which permits to differentiate osteochondrosis evolution from recessive patterns. Finally, MRI clearly showed the increased equatorial diameters of the involved femoral heads and the associated decrease in polar diameters, which is essential to study the biomechanics of hip osteochondrosis and therefore to plan treatment. CONCLUSIONS: MRI, even with coronal sequences and T1-weighting only, permits: 1) to image normal hips and hip osteochondrosis, especially in early and late childhood; 2) to clearly define cephalocotyloid relationships; 3) to depict the actual anatomic margins of the head and its structure; 4) to investigate the head cartilage extent and to locate the ossification nucleus. These morphologic and structural data are very useful to diagnose and manage hip osteochondrosis in the evolutive age. MRI shows abnormal changes in anatomic structures which are not seen with conventional radiography and demonstrates the evolution of the osteochondrosis process over time. In children over six, at the end of the ossification process of the head cartilage, conventional radiography alone is often sufficient to depict cephalocotyloid relationships and the MR diagnostic criteria of bone-cephalic diseases are similar to those used in adult hip studies.

Adult↗
PubMed1997

[MR cholangiopancreatography: technique, indications and clinical results].

INTRODUCTION: MR cholangiopancreatography (MRCP) is a new noninvasive imaging technique for the study of biliopancreatic disorders, providing projectional images of the biliary tree and pancreatic duct without any contrast agent. MATERIAL AND METHODS: We used different sequences, with both breath-hold and nonbreath-hold techniques, to acquire MRCP images, first based on GE and then on FSE sequences. FSE images provide higher SNR and are less susceptible to artifacts (metal objects, motion and blood flow artifacts). At the Department of Radiology of the University of Rome La Sapienza, we acquired MRCP images with non breath-hold, 3D fat-suppressed TSE sequences (TR = 3000-2000, TE 700, turbo factor 128) optimized on a .5T magnet with 15 mT/m gradients. No patient preparation or sedation was required, although antiperistaltic drugs and oral administration of tap water were preferred. Four hundred and thirty patients were examined, all of them with an indication to conventional cholangiography. RESULTS: MRCP depicted the whole common bile duct and the first-order intrahepatic branches in all the normal cases. Its accuracy in identifying biliary obstruction level and site was 100%, versus 94.6% in characterizing its cause. MRCP had 96.3% diagnostic accuracy in choledocholithiasis, with some false positives and false negatives caused by: 1) small stones missed on MIP reconstructions; 2) signal loss due to complete CBD obstruction by stones; 3) pneumobilia; 4) differential diagnosis between small stones and air bubbles. The main role of MRCP in benign strictures is to provide a detailed map of the biliary tract for better treatment planning. In particular, MRCP is extremely useful in hepaticojejunostomy patients, where ERC is not indicated because of postoperative anatomical changes. Both conventional MRI and MRCP are important in malignant strictures to identify the lesion and to characterize and stage it. Finally, MR pancreatography is very useful to follow up chronic pancreatitis patients because it shows Wirsung duct strictures and dilatations, intraductal filling defects and, in some cases, the communication between the pseudocyst and the pancreatic duct. CONCLUSIONS: MRCP combined with conventional MRI can completely replace CT and ERCP in bilio-pancreatic disorders.

Adult↗
PubMed1996

MR cholangiopancreatography (MRCP) at 0.5 T: technique optimisation and preliminary results.

The aim of our study was to evaluate the feasibility of MR cholangiopancreatography (MRCP) at 0.5 T. To our knowledge no previous studies of MRCP have been performed at mid-field strength. Thirty-one patients with dilated biliary systems were examined with three-dimensional MRCP. All patients were studied with a 0.5 T superconducting magnet. A three-dimensional turbo spin-echo (TSE) sequence was acquired (TR = 5000 ms, TE = 244 ms, echo train length = 45; acquisition time = 14 min 10 s). Coronal images were post-processed with the MIP algorithm. Recently, the parameters have been optimised (TR = 3000 ms, TE = 700 ms, echo train length = 128), reducing the acquisition time to 3 min. Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 26 cases; 5 patients underwent percutaneous transhepatic cholangiography PTC. MRCP and ERCP images were evaluated by an experienced radiologist and an endoscopist. MRCP of diagnostic quality was acquired in all patients. Choledocholithiasis was correctly evaluated by MRCP in 12 of 12 patients, compared with 11 correct diagnoses by ERCP. The presence and the level of the stricture were accurately shown in 16 of 16 patients with MRCP and in 13 of 16 patients with ERCP. The peripheral biliary tree above the obstruction and pancreatic duct were better evaluated by MRCP in all cases. In 3 of 3 patients who had undergone bilio-enteric surgery, a correct evaluation of the site of the anastomosis was possible with MRCP. It is concluded that MRCP performed at mid-field strength allows good visualisation of the dilated biliary system. Excellent results have been obtained on comparison with ERCP. MRCP performed at mid-field strength could have the same clinical value as high field strength MRCP.

Adult↗
PubMed1996

An integrated approach to senology education: combination of a hypermedia program with a multimedia archive.

The aim of this work was to demonstrate the computerized system on senology, which combines a hypermedia application to a multimedia didactical archive, integrated with a radiological information system. These applications have been developed on Macintosh computers using the softwares Supercard and 4th Dimension. The hypermedia application deals with basic principles of anatomy as well as the radiologic semeiology and pathology through different imaging techniques in order to illustrate basic principles. Thus, students can modify their learning pathways and the timing as they wish. Limitations are related to time consumption in preparing the programs and technical difficulties in expanding them. Multimedia archive allows to classify a large number of difficult and uncommon clinical cases, creating an easily updatable teaching file in digital format which considerably improves access to stored image data, also reducing loss of films and film degradation. From initial experiences we conclude that these systems are valid devices in information and up to date for physicians dedicated to the study of breast pathology.

Breast↗
PubMed1996

MRI postoperative monitoring in patients surgically treated for aortic dissection.

In most cases, surgery of aortic dissections repairs only the ascending portion of the aorta, leaving a residual dissection in the arch and descending aorta. We studied 17 patients operated upon for type A aortic dissection. A total of 42 magnetic resonance imaging (MRI) examinations were performed, with two to five studies per patient (mean 2.47). The studies were done between 5 weeks and 47 months (mean 17.5 months) after surgery. The patients were evaluated by MRI using gated spin-echo and gradient-echo sequences on axial and oblique sagittal views, and in selected cases, coronal views. A high incidence of abnormalities was observed. Pericardial hematoma was observed in 11% of cases, aortic and branch involvement in 41%, abdominal aortic branch involvement in 47%, dilatation of native aorta in 58%, and extension of dissection in 10%. New complications were detected during follow-up in 53% of patients. MRI was helpful in the follow-up of patients operated upon for aortic dissections, owing to its noninvasiveness and multiplanarity. By means of this technique, it was possible to obtain information about the natural history of the disease, as well as information useful for subsequent treatment.

Adult↗
PubMed1996

Radiology information and image management system: new approach to PACS with hypermedia capabilities of personal computers.

A system for archiving patient data and images was developed, installed, and evaluated in a radiology department. The system was developed with a relational database program for use with commercially available computers linked with an Ethernet network. The main options of the system are those of a conventional radiology information system: scheduling, registration, examination execution, reporting, archives and statistics, and system administration. However, the main feature of the system is the image archiving capability. Images are associated with patient records after capture by direct acquisition of the video signal or by scanning. Only relevant pathologic images are archived and a commonly employed compression algorithm is used, reducing the total memory requirement for each case to 200-600 kbytes. The diagnosis is still made by reading the original images. The low-resolution images stored in the system have an important role in teaching and consultation and as a first-line archive. Good results have been obtained with this system, which is used by medical and nonmedical staff without any special training.

Humans↗
PubMed1996

[Color Doppler echography in the study of obstruction-related lung collapse].

The typical US pattern of obstructive atelectasis consists in a triangular hypoechoic area with anechoic bands inside related to fluid-filled bronchial structures--the US fluid bronchogram sign. According to some authors, this US sign within a chest mass indicates pulmonary parenchyma disease. Furthermore, it suggests the diagnosis of lung collapse. Sixty-one patients with obstructive atelectasis confirmed with conventional radiography, conventional and computed tomography, and bronchoscopy were submitted to B-mode and color-Doppler US to assess the importance of the US fluid bronchogram sign in obstructive pulmonary atelectasis. In this condition, B-mode US showed tubular anechoic bands in 59/61 patients. Power Doppler venous sampling showed a Doppler spectrum with marked phase oscillations. Arterial sampling showed a Doppler spectrum with high distal impedance-with poor or totally absent diastolic component. To conclude, in the atelectasis area, B-mode US showed in 96% of patients some anechoic bands with no apparent pulsatility. Color-Doppler showed color flow in 100% of cases, which confirmed the vascular nature of the masses. Thus, the US fluid bronchogram, which is frequently described in the literature, was never observed in our series. Power Doppler spectral flow analysis can be useful in the diagnosis of obstructive atelectasis because it depicts the hemodynamics of atelectasis parenchyma. Indeed, the arterial spectrum with high distal resistance is consistent with the effects of hypoxia on intra-atelectatic blood vessels. Further research is necessary to assess the role of color-Doppler US in the hemodynamic study of intra-atelectatic vessels. However, our preliminary results open new perspectives for the acquisition of physiopathologic data on abnormal blood flow in obstructive atelectasis.

Adult↗