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R Pozzi Mucelli

Publications and source records attributed to R Pozzi Mucelli.

53 records · Page 3Linked to original sources

[Adrenal tuberculosis in 13 patients with Addison's disease. CT findings].

A series of thirteen cases of adrenal tuberculosis with Addison's disease is presented. At the onset of disease, CT findings consisted of an enlargement of both glands, with peripheral enhancement after contrast medium was injected. The CT differential diagnosis among tubercular, metastatic and amyloidotic etiology was not possible. When the course of the illness was favourable, CT showed a generalized glandular atrophy with calcifications. In two fatal cases, the diagnosis could be made only at post-mortem examination.

Addison Disease↗

[Results of a study of the resected stomach using biphasic and traditional technics].

The authors report their results in the evaluation of 181 gastroresected patients. All these cases were clinically selected; 96 of them have been examined by using standard biphasic-contrast examination and 85 by using traditional radiological technique. Their aim was to determine the contributions of the new technique in the evaluation of the resected stomach and to effect a critical review of the traditional one. Their results show that the standard biphasic-contrast examination carries out a notable improvement in the radiological diagnostic accuracy. It reduces greatly the discrepancy between radiology and endoscopy.

Contrast Media↗

Ultrasonography of the pancreas. 3. Doppler imaging.

Ultrasonography is probably the most widely used medical imaging technique. In fact, its non-invasivity, portability, widespread distribution and good clinical results have made it the preferred method for a first imaging approach to patients in a large variety of clinical settings. Ultrasound technology is advancing rapidly, aimed to increase image quality. In particular, increased color-Doppler sensitivity is contributing to the diagnosis and staging of pancreatic disease. Doppler studies are in fact integral part of ultrasound examination of the pancreas evaluating the peripancreatic vascular structures enclose portal vein, splenic artery and vein, superior mesenteric artery and vein, aorta, and inferior vena cava. While flows in all peri-pancreatic vessels are well recognized, only few parenchymal vessels are usually appreciable in normal conditions. Anyway the increased Doppler sensitivity allows the visualization of smaller peri-pancreatic and intra-pancreatic vessels. This article will review the technical background underlying the clinical application of Doppler ultrasonography in pancreatic imaging, with particular emphasis to normal vascular anatomy of the pancreas, and to the main applications of Doppler techniques in the different pancreatic pathologies.

Humans↗

Ultrasonography of the pancreas. 4. Contrast-enhanced imaging.

The introduction of contrast-enhanced ultrasonography (CEUS) has lead to great developments in the diagnostic capabilities of ultrasound. Second generation contrast media, characterized by harmonic responses at low mechanical index of the ultrasound beam, have already proven usefulness in the study of the liver but other abdominal organs can take advantage from the dynamic study during continuous ultrasonographic scans. The dynamic observation of the enhancement allows the perfect evaluation of the abdominal organs perfusion. The perfusion of the pancreas is well correlated to the semeiology of the gland parenchymography at CEUS. The study of the pancreas is a new and promising application of CEUS. CEUS can be used to better identify pancreatic lesions respect to conventional Ultrasound (US) or to characterize pancreatic lesions already visible at US. Moreover the staging of some pancreatic lesions can be improved by the use of contrast media. This article will review the clinical application of CEUS in the different pancreatic pathologies.

Contrast Media↗

Ultrasonography of the pancreas. 5. Interventional procedures.

Interventional ultrasonography (US) is often used for the diagnosis and therapy of pancreatic pathologies, and its diffusion has definitely modified the diagnostic and therapeutic management of some diseases. US is particularly suitable for targeting percutaneous pancreatic interventional procedures and important technical features contribute to this result. First of all, US is dynamic, and thus the ongoing procedure can be continually monitored. Then, the high spatial resolution achieved by US imaging in recent years, its speed and availability and the low-cost of the technique, together with the technical features, have led to an ever-increasing use of US in pancreatic interventional procedures. This article will review the application of US as guide of diagnostic and interventional procedures in the different pancreatic pathologies.

Biopsy, Needle↗

Ultrasonography of the pancreas. 7. Intraoperative imaging.

The usefulness of intraoperative ultrasonography (IOUS) has been documented in the Literature since the Eighties and, although its main applications are in hepatobiliary and pancreatic surgery, it has been used also in neurosurgery, cardiovascular and endocrine surgery. The continuous technical developments have led to an increase in the diagnostic accuracy of IOUS from the Eighties to now. The use of IOUS has increased in time together with the technical innovations until, mainly in the midnineties, its value was recognized by many surgeons. This results have been obtained with scanners that allow to depict fine anatomical details and detect small lesions in real time with extremely high spatial resolution. IOUS is able to shows fine details, such as primary or secondary lesions not detectable with other preoperative imaging modalities or tumor extension and its relationship with vessels. Assessment of resectability by IOUS may determine important changes in therapeutic planning. The role of IOUS, however, has recently been down-sized, especially in those centers where preoperative imaging is advanced. This article will review the clinical role of pancreatic IOUS in the different pancreatic pathologies.

Humans↗

[Current role of color Doppler ultrasound in acute renal failure].

Acute Renal Failure (ARF) is characterized by a rapid decline of the glomerular filtration rate, due to hypotension (prerenal ARF), obstruction of the urinary tract (post-renal ARF) or renal parenchymal disease (renal ARF). The differential diagnosis among different causes of ARF is based on anamnesis, clinical symptoms and laboratory data. Usually ultrasound (US) is the only imaging examination performed in these patients, because it is safe and readily available. In patients with ARF gray scale US is usually performed to rule out obstruction since it is highly sensitive to recognize hydronephrosis. Patients with renal ARF have no specific changes in renal morphology. The size of the kidneys is usually normal or increased, with smooth margins. Detection of small kidneys suggests underlying chronic renal pathology and worse prognosis. Echogenicity and parenchymal thickness are usually normal, but in some cases there are hyperechogenic kidneys, increased parenchymal thickness and increased cortico-medullary differentiation. Evaluation of renal vasculature with pulsed Doppler US is useful in the differential diagnosis between prerenal ARF and acute tubular necrosis (ATN), and in the diagnosis of renal obstruction. Latest generation US apparatus allow color Doppler and power Doppler evaluation of renal vasculature up to the interlobular vessels. A significant, but non specific, reduction in renal perfusion is usually appreciable in the patients with ARF. There are renal pathologic conditions presenting with ARF in which color Doppler US provides more specific morphologic and functional information. In particular, color Doppler US often provides direct or indirect signs which can lead to the right diagnosis in old patients with chronic renal insufficiency complicated with ARF, in patients with acute pyelonephritis, hepatic disease, vasculitis, thrombotic microangiopathies, and in patients with acute thrombosis of the renal artery and vein. Contrast enhanced US is another useful diagnostic tool in patients with ARF which has been recently introduced in clinical practice. Microbubble administration may reduce technical failure in the evaluation of the renal artery. Moreover, perfusion defects due to stenosis or thrombosis of the renal segmentary vessels are better recognized. New diagnostic possibilities of enhanced US include evaluation of both cortical and medullar vessels, and functional evaluation of renal perfusion. Measuring the transit time of the microbubbles is useful for the diagnosis of renal artery stenosis and, in transplanted kidneys, for differential diagnosis between ATN and acute rejection.

Acute Kidney Injury↗

Renal angiomyolipoma: typical and atypical features.

Renal angiomyolipoma is an uncommon lesion, well-known to the radiologists as one of the few lesions for which a specific diagnosis can be achieved on the basis of radiological findings. It contains variable amounts of adipose tissue, smooth muscle and vessels. It usually grows as single lesion, and it can be isolated or associated with tuberous sclerosis or with the more rare lymphangioleiomyomatosis. From a radiological point of view there are typical aspects that allow a confident diagnosis, whereas more rarely there are atypical aspects that make the diagnosis more controversial. In this review the clinical, macro and microscopic morphological aspects of angiomyolipoma are presented as well as the therapeutic approaches that can be adopted in different circumstances. The most frequent and the atypical characteristics that can be appreciated with diagnostic imaging are described as well.

Angiomyolipoma↗

[Intraoperative iliac angioplasty and distal revascularization: is it an efficacious method in the high-risk patient?].

The fact that iliac femoro-popliteal areas are both simultaneously interested in some high risk patients, frequently is cause of several problems in the indication of the surgical treatment. So, we have decided to practice an iliac Angioplasty peroperatively as a method of iliac revascularization in association with the surgical repairment of the femoro-popliteal area. Results of 20 patients with 23 surgical procedures during a period of two years is reported.

Aged↗

Three-dimensional rotational angiography of the carotid arteries with high-flow injection from the aortic arch. Preliminary experience.

PURPOSE: Three-Dimensional Rotational Angiography (3DRA) is a new technique based on a rotational angiographic acquisition able to display arterial vessels in a 3D rendering mode. The system was mainly developed for neuroradiological evaluations but preliminary extracranial experiences have also been reported. The aim of our work was to compare the results of three-dimensional angiography of the carotid arteries done with high-flow injection of contrast medium from the aortic arch with the results of selective angiography. MATERIALS AND METHODS: Twenty patients underwent digital angiography of the supra-aortic vessels in order to quantify a stenosis of the carotid bifurcations previously detected at Doppler Ultrasound. Examinations were performed with the Philips Integris Allura system provided with the rotational angiography (RA) tool connected to a workstation for three-dimensional reconstruction able to display vessels in a 3D fashion (Volume Rendering, Gradient Rendering, Shaded Surface Display), automatically remove bone structures (cervical spine, calcified plaque, etc.) and perform an automatic analysis of the vessel diameter and surface area at the point of major stenosis and in the disease-free vessel segments above and below. The carotid evaluation was done either with selective catheterization and the two standard AP and LL projections and with RA after contrast medium injection from the aortic arch followed by 3D reconstruction. RESULTS: The comparison of the selective angiography and three-dimensional images was possible in 37 out of 40 carotid bifurcations (3 internal carotid arteries were occluded) and a good diagnostic quality was obtained in 35 out of 37 cases with an high correlation in the degree of stenosis. In 2/37 cases with calcified plaques the degree of stenosis was effectively demonstrated only after electronic subtraction of the calcified component of the plaque. CONCLUSIONS: The technique we propose proved to be feasible in all cases with a good correlation in the quantification of the degree of stenosis. The practical advantage of our technique is the almost complete exclusion of risks of neurological complications due to selective catheterization, and reduced examination time.

Aged↗

[Cardiac complications of intravenous digital angiography. Comparison of ionic and nonionic contrast media].

The review of 1405 digital intravenous subtraction angiographies carried out in the period may 1982-february 1985 showed in about 2% of the cases cardiac symptoms, which arose during or after the examination. In the great majority of the cases the symptomatology was characterized by angina pectoris. In order to better understand these data and analysing the results of the literature, a trial has been performed in 100 patients who underwent DSA. They have been divided into two groups in which two different contrast media, ionic (sodium meglumine diatrizoate) and non ionic (iopamidol) have been randomly injected. A detailed cardiologic anamnesis has been collected and EKG has been performed before and after each injection with pre-established gaps. The results showed that the incidence of cardiac symptoms and EKG variations is lesser with the non ionic contrast medium: therefore this agent is to be preferred at least in patients at risk from cardiologic point of view.

Acute Disease↗

[Correlations between nephrotomography and arteriography in the diagnosis of renal mass lesions (author's transl)].

A series of 325 patients with renal mass lesions were examined by means nephrotomography during the years 1973-76; 85 of them (26%) underwent angiographic investigations. The basic findings observed with nephrotomography are described followed by the criteria which have suggested the necessity of the arteriographic examination. The analysis of the correlations between the two methods, shows the criteria which may limit the use of renal arteriography.

Hematoma↗

[Diagnostic imaging and interventional therapy in hepatocarcinoma. Multicenter study of 290 cases].

We report the results of a multicenter study on the diagnosis and interventional therapy of hepatocellular carcinoma (HCC). The first aim--diagnosis--was to evaluate the sensitivity of 4 imaging techniques, namely ultrasonography (US), Computed Tomography (CT), digital arteriography (DSA) and Lipiodol CT (LCT), in HCC detection. The accuracy of these techniques was also investigated in tumor staging, which is important for treatment planning. Two hundred ninety patients underwent this imaging protocol. The patients were classified by tumor spread into three groups, namely group 1 (single HCCs < 5 cm), group 2 (multifocal HCCs with max. 3 nodules or tumor volume < 80 cc), group 3 (multifocal HCCs with more than 3 nodules and/or tumor volume > 80 cc). US and CT diagnosed more cases as group 1 and fewer cases as group 3 than DSA and LCT; the latter two techniques gave a similar classification. With LCT as the gold standard, US and CT understaged 27.9% and 26.5% of cases, respectively. Even though LCT is known to have 53% sensitivity, it is currently the most sensitive preoperative investigation and therefore the best tool for treatment planning. In surgical patients, however, intraoperative US, with its nearly 100% sensitivity, is suggested. The second aim--treatment--consisted in assessing the therapeutic efficacy of intraarterial chemoembolization (CEAT) versus percutaneous ethanol injection (PEI) in non advanced HCC and of CEAT versus no treatment (NT) in advanced HCC. Treatment efficacy was evaluated with the following randomized protocols: PEI versus CEAT in group 1, PEI versus CEAT in group 2 and CEAT versus NT in group 3. The data were analyzed relative to 215 patients for 6 to 30 months. The Kaplan-Meier method was used to calculate survival rates, which were, at 24 and 30 months, 72% and 72% for PEI and 72% and 52% for CEAT in group 1, 52% and 28% for PEI and 70% and 50% for CEAT in group 2 and finally 30% and 20% for NT and 45% and 30% for CEAT in group 3. In group 1, PEI appeared markedly superior to CEAT. In group 2, the difference between PEI and CEAT was not statistically significant; the results in this group indicate that CEAT should be considered when three nodules are present because of PEI invasiveness in these cases. In group 3, CEAT results were definitely better in the first two years, but there was no difference with NT patients at the end of the third year. Therefore, CEAT is indicated in advanced HCC because it improves the survival rate in the first 24 months. After this period, the survival time is not modified by treatment.

Antineoplastic Agents, Hormonal↗

[Morpho-functional study of the kidney in patients with kidney disease and liver disease with magnetic resonance].

INTRODUCTION: We studied renal function and perfusion after the i.v. injection of Gd-DTPA-BMA, a nonionic paramagnetic contrast agent, to assess renal morphology and function in normal subjects, in renal insufficiency patients and in patients with hepatic failure and normal renal function. The latter were chosen because some patients with advanced hepatic failure may suffer from the hepatorenal syndrome, characterized by severe vasoconstriction in the renal cortical vessels. We investigated if dynamic MRI can detect early renal perfusion abnormalities in the patients who will eventually develop this syndrome. MATERIAL AND METHODS: Thirty MR examinations were carried out on 30 subjects after the i.v. injection of Gd-DTPA-BMA. Our series consisted of: 10 normal subjects; 10 renal insufficiency patients; 10 patients with hepatic failure and normal renal function. MR examinations were performed on a Philips ACS II scanner operating at 1.5 T. Two sequences were carried out in all cases: T1-weighted SE and T1-weighted TGE sequences after the bolus injection of .1 mmol/kg contrast agent. Renal longitudinal diameter and parenchymal thickness were measured in all cases and signal intensity time curves were always made. The signal intensity of the cortex, corticomedullary junction, medulla and pyelocaliceal system of each kidney was measured using a region of interest (ROI). The signal intensity curves were made considering quantitative parameters, including the area below the curve (ASC), the peak (P) and the time to peak (T-P). RESULTS: Longitudinal diameter and parenchymal thickness values were significantly lower in renal insufficiency patients than in normal subjects. Four phases were demonstrated after i.v. contrast agent injection in normal subjects, namely A) the cortical phase, B) the corticomedullary junction phase, C) the medullary phase, D) the pyelocaliceal phase. No signal intensity decrease in the medullary and pyelocaliceal curves was observed in renal insufficiency patients. Signal intensity curves values were lower in hepatic failure patients than in those with normal renal function. Hepatic failure patients could be divided into two groups: 5 patients had low P and ASC values and 4 had normal P and ASC values. The patients with lower P and ASC values developed the hepatorenal syndrome within a few months of the MR examination. DISCUSSION: Signal intensity decreased in the pyelocaliceal system phase in normal subjects because of the high paramagnetic contrast agent concentration. The lack of signal intensity decrease in renal insufficiency patients was caused by the reduced capability of concentrating Gd-DTPA-BMA. Lower signal intensity values in hepatic failure patients may be considered an early sign of the hepatorenal syndrome.

Adult↗

[Virtual endoscopy of the nasal cavity and the paranasal sinuses with computerized tomography. Anatomical study].

INTRODUCTION: Virtual endoscopy is a new 3D technique which permits to depict the inner surface of anatomic cavities. We report our experience in the study of the nasal cavity and paranasal sinuses. MATERIAL AND METHODS: CT examinations of the maxillofacial region were obtained using 1.5 or 3.0 mm slices, 1.5 or 3.0 mm table feed, 120 kV, 140 mA, 2 s scan time, standard and high resolution algorithms for bony structures and a field of view of 14-16 cm. The images were transferred on a workstation and processed with the Navigator virtual endoscopy software (General Electric). A threshold value ranging -300 to -550 UH was applied. RESULTS: We report a series of virtual images of the nasal cavity which includes rhinopharynx vault, torius tubarius, choanae, turbinates, tubal orifice and osteomeatal complex. Moreover, images of frontal sinus and tear duct, of polyps and fracture of maxillary sinus are also presented. 3D virtual endoscopy provides a clear visualization of the anatomic structures of the nasal cavity and sinuses. The images are similar to those of conventional endoscopy. Moreover virtual endoscopy visualizes the paranasal sinuses, which are not accessible at conventional endoscopy. The main limitations of this new technique are the arbitrary choice of the threshold value and the homogenization of different tissue densities, which reduces the contrast resolution. CONCLUSIONS: Virtual endoscopy can presently be considered a complementary technique of the standard axial and coronal CT examination. It provides an effective demonstration of the anatomy of these structures and shows areas which are difficult to visualize with conventional endoscopy. This technique could be of help in didactical activity; its clinical application has to be verified.

Humans↗