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R S Pozzi Mucelli

Publications and source records attributed to R S Pozzi Mucelli.

At least 19 recordsLinked to original sources
PubMed1996

"Aggressive" renal angiomyolipoma.

PURPOSE: We describe the US and CT examinations of 4 patients with renal angiomyolipoma with an "aggressive" appearance, and review the literature. MATERIAL AND METHODS: The imaging findings in 4 patients with benign renal angiomyolipomas associated with thrombosis of the renal vein and/or inferior vena cava are presented. In one case, enlarged lymph nodes at the renal hilum were found. RESULTS: CT demonstrated fat densities within both tumor and thrombus. In one patient, small lymph nodes with low density internal areas were detected in the para-aortic region. When considering our patients together with those reported in the literature, we found that most angiomyolipomas with venous invasion were large and centrally located within the kidney. Venous thrombosis was observed in 9 lesions of the right kidney, and in only 4 of the left one; detection of the site of origin was impossible in one case. One patient only had symptoms due to the thrombus; 10 had problems due to the tumor; and 3 were asymptomatic. Only 4 patients with pararenal enlarged lymph nodes have been reported on in the imaging literature. Fat-containing nodes were detected by CT in one case only; the others had enlarged nodes of soft-tissue density. In one patient the diagnosis of hamartomatous lymph node invasion was established by angiography. CONCLUSION: In patients with renal angiomyolipoma, demonstration of both fatty thrombus and the fatty infiltration of lymph nodes of the renal hilum cannot be regarded as an indication of malignancy, but only of local aggressive behavior. Although surgery is commonly contemplated to prevent symptoms from venous thrombosis, conservative treatment seems possible. Detection of enlarged lymph nodes of soft tissue density may cause difficult diagnostic problems, with the diagnosis addressed only by the presence of associated lesions. Increased awareness that renal angiomyolipoma can sometimes appear "aggressive" could help to prevent such lesions from being considered malignant, and thus avoid surgical confirmation of their nature.

Adult↗
PubMed1995

[Magnetic resonance of tibiotalar and subtalar joints. Normal anatomy].

Fifty-three ankles of 29 normal volunteers were examined with Magnetic Resonance Imaging (MRI) to improve the anatomical MR knowledge of tibiotalar and subtalar joints. The aim of our study was therefore to assess the visibility of articular cartilages, tendons and ligaments of the ankle and to define the best scan plane for their visualization. MR studies were performed with SE T1-weighted sequences on the sagittal, coronal and axial planes. The visibility of articular cartilages was 70.8% for the tibiotalar joint and 56.3% for the subtalar joint. All ankle tendons and four of the eight ankle ligaments considered in our study were assessed, at least on one of the sagittal, coronal or axial planes, with over 70% visibility. The deltoid ligament was detected in 95% of the cases on coronal images, the anterior and the posterior talofibular ligaments were seen respectively in 82% and in 75% of the cases on axial images, while the interosseous ligament was detected in 87.5% of the cases on sagittal images. Our study assessed both the capabilities and the limitations of MRI in the detection of anatomical structures of the tibiotalar and subtalar joints and defined the best scan plane for their visualization.

Achilles Tendon↗
PubMed1991

[Echography: problems and errors in the diagnosis of renal masses].

US plays an extremely important role in the diagnosis of renal masses. However, a number of diagnostic difficulties still exists in both identification of the mass and definition of its nature. The most frequent causes of diagnostic errors are discussed. Errors may be due to the radiologist, to technical limitations, and to the lesion itself. The radiologist is responsible for inexperience and negligence (incorrect application of the technique, limited clinical information, poor knowledge of US findings). Technical limitations are due to poor spatial and contrast resolution, to extremely fat patients, and to artifacts. As far as lesions are concerned, cystic and solid masses must be distinguished, since the problems are different. As for cystic lesions, problems are relative to their visualization and to the definition of their nature in cases of atypical or complex cysts, due to the complexity of some US findings. The latter involve both cystic wall and content and are related to calcifications, septa, vegetations, blood, purulent debris. In case of solid masses, problems concern the identification of small renal tumors, the differentiation among the various anatomical variants, the differential diagnosis of benign from malignant tumors, and the evaluation of tumor extent. The authors conclude that, whereas operator-dependent errors can be avoided, those inherent to technical parameters and to the lesion itself represent the diagnostic limitation of US.

Diagnostic Errors↗
PubMed1991

[Computerized tomography: problems and errors in the diagnosis of renal masses].

The diagnostic imaging of renal masses has greatly benefitted from US and CT. Nevertheless, a certain number of problems and errors are still present, and they must be discussed once more. In the authors' experience, problems and errors have 3 fundamental causes: operator, examination technique and complex patterns of renal masses. The latter is the most important cause of error in CT diagnosis. Complex patterns are seen in a limited number of cystic masses--i.e., hemorrhagic, inflammatory, and septated cysts, and cystic tumors. Hemorrhagic cysts, if hemorrhage is not recent, can cause some diagnostic difficulties since the typical high density of the recent hemorrhage is no longer present. Other renal masses may appear hyperdense on unenhanced CT scans, and therefore they must be considered in the differential diagnosis. Inflammatory cysts and abscesses are sometimes difficult to differentiate from other masses due to their aspecific appearance; clinical correlation is important in these instances to support CT diagnosis. Multiseptated cysts and cystic tumors cause huge problems of differential diagnosis. A good knowledge of differential CT findings is sure to reduce the problems in differentiating benign from malignant tumors and, among the latter, the different histotypes and metastases, when present as solitary masses. Also in this case, the correlation between CT, clinical history and other modalities can reduce the number of questionable cases.

Diagnostic Errors↗
PubMed1989

Ultrasonography in oncology. A review.

The applications of ultrasonography (US) in oncology have rapidly increased during the past few years. Technical improvements, development of new technologies, easy availability, and non-invasiveness are some of the reasons for the rapid diffusion of US. Nowadays a large number of malignancies, both superficial and deep-seated, can be examined by US. In order to give an overview of the present role of US in oncology it is necessary to discuss many different topics including tissue characterization, diagnostic role, staging, follow-up and future developments.

Humans↗
PubMed1988

Urinary beta-1-galactosyl-0-hydroxylysine (GH) as a marker of collagen turnover of bone.

beta-1-galactosyl-0-hydroxylysine (GH) was measured in the urine of 59 women and 48 men, aged 30-79 years, by High Performance Liquid Chromatography (HPLC) of the dansylated derivative. Vertebral mineral density, measured by quantitative computed tomography (QCT), and urinary GH were inversely correlated (r = -0.74; P less than 0.001). High rate of bone mineral loss is associated with a high urinary GH excretion. Measurement of GH in urine provides a simple and noninvasive method for the evaluation of the extent of bone resorption in large groups of subjects and appears to be more specific than urinary hydroxyproline excretion.

Aging↗
PubMed1988

[Computerized tomography of the spine in the evaluation of multiple myeloma].

Computed Tomography (CT) of the spine was performed on 17 patients with myeloma in order to assess the role of the technique in recognizing and evaluating the extent of the lesions. Myelomatous lesions followed two patterns at CT: first of all, multiple focal lesions, whose density is either solid, liquid, or fatty; second, an extensive pattern involving the spongiosa of the vertebra, including the posterior arch. CT detected more lesions than conventional radiology; furthermore, the extent of the lesions was much better demonstrated by CT. CT should thus be performed: a) in case of pain and/or neurological findings in negative radiological examinations; b) to evaluate the extent of myelomatous lesions (mainly in the spine); c) in solitary myeloma CT may be performed on different bone segments with clinical symptomatology but normal X-ray findings.

Humans↗
PubMed1987

[Instrumental diagnosis of non-glandular superficial inflammation].

The study of soft tissues has greatly improved since the introduction of ultrasonography (US) and computed tomography (CT). In order to define the role of instrumental investigations, 51 patients affected by non glandular superficial soft tissue masses underwent US and 9 were also examined with CT. US proved to be accurate to define the size, the structure of the mass (93%), the benign or malignant nature (91%). US was also useful for percutaneous biopsy. However, US cannot be considered the only investigation because it does not give enough data about bony and articular structures: a conventional X-ray film must be performed in order to define the relation of the mass with the adjacent bone and to clarify the possible presence of fatty tissue in a solid mass shown at US. CT has a role in case of large masses, surrounding a bone diaphysis, when the malignant nature is suspected and to define the relationship with vessels and muscles.

Abscess↗
PubMed1987

[Clinical applications of an instrument of resistive-type magnetic resonance of new design].

In Magnetic Resonance, resistive magnets give a poorer image quality than superconductive magnets, due to the lower magnetic field strength, uniformity and stability of resistive magnets. However, recent developments in resistive magnet technology have improved the field strength, as well as its uniformity and stability. The aim of this paper is to report the preliminary results of a new resistive magnet based on a iron core technology with transverse field orientation, operating at 0.38 T. The clinical experience based on about 200 studies of the brain, spinal cord, cervical, thoracic, lumbo-sacral spine, heart, abdomen and joints was promising in most clinical applications with results comparable to those of superconductive magnets with a similar field strength.

Brain↗
PubMed1986

[3-dimensional craniofacial computerized tomography].

Computed tomography allows today to reconstruct three-dimensional (3D) images from axial scans. The authors report their experience in cranio-facial pathology achieved in two Departments of Radiology (University of Trieste, Italy and University of Stanford, California). 3D images have been realized using two different softwares, one of which allows to reconstruct both soft tissue and bone structures. The applications in maxillo-facial traumas, cranio-facial malformations and head tumours are discussed. 3D images turned out to be very useful for the optimal visualization and for the spatial demonstration of the lesion and have potential applications in cranio-facial surgery and radiotherapy.

Facial Bones↗
PubMed1986

Three-dimensional computed tomography of the acetabulum.

Acetabular fractures represent a complex variety that are classified in different types. Conventional radiology is often inadequate to demonstrate and classify the fractures. Computed tomography (CT) has already been shown to be superior in this field. A further advantage of CT is represented by the recent availability of three-dimensional (3D) images that are realized from axial CT scans by means of a new software. The Authors report the applications of this new software to the study of the normal acetabulum and in patients with fractures. 3D images allows an effective demonstration of the fracture, its irradiation and the dislocation of bone fragments. The information is contained in one or few images rather than many axial images. Therefore the role of 3D images may be considered complementary to axial CT scans.

Acetabulum↗
PubMed1985

[Sialography, echography and computerized tomography in the study of the parotid region].

The diagnostic accuracy of sialography and ultrasonography (US) in the evaluation of parotid masses is evaluated. Furthermore the role of computed tomography (CT) in this pathology is discussed. In the personal experience US proved to be the best method in the recognition of a parotid tumor while sialography was superior in defining the intra or extraparotid site. The two investigations showed the same accuracy in the definition of benign or malignant nature of the mass. Therefore we consider US the only investigation in most instances; sialography could be performed when the site of the lesion is uncertain or an inflammatory lesion is suspected. CT is never the first investigation; its use is limited to a low number of cases, mainly for the evaluation of large masses and when the association US-sialography does not allow a sure diagnosis.

Adenolymphoma↗
PubMed1985

[Clinical control of the quality of dynamic echography].

The performances of 4 real-time scanners (2 mechanical sector scanners and 2 linear electronic scanners) have been tested. The clinical test used was the examination of liver, gallbladder and biliary tract and in other circumstances the examination of kidney and breast. The quality of the scanners has been judged on the ground of four parameters: the diagnostic quality of the image (DQI) the overall quality of the image (OQI), the efficiency of the exploration (EE) and feasibility of use (FU). The ideal conditions of use for each technology are described and the authors emphasize the impact of improved technology on the quality of the ultrasonographic scanners.

Gallbladder Diseases↗
PubMed1985

Computed tomographic follow-up in a case of Addison's disease.

Addison's disease of the adrenal glands presents with different pathological findings depending on the stage. In the acute phase the adrenal glands are bilaterally enlarged while in the chronic phase the glands are small and calcified. A case of Addison's disease with follow-up over a period of a year by CT is reported. CT showed the evolution of the adrenal glands from bilateral masses to small calcified glands. The differential diagnostic problems in the acute phase are also discussed.

Addison Disease↗
PubMedDate not supplied

MR imaging of adrenal myelolipomas.

The magnetic resonance (MR) images in six patients with seven adrenal myelolipomas are presented. Four lesions involved the right gland, and three the left; they ranged from 3 to 12.5 cm in diameter. Magnetic resonance was able to image all lesions. Using T1-weighted sequences, three structural patterns were observed; (a) homogeneous masses with intensity equal to adjacent fat (three cases); (b) heterogeneous masses with fat intensity areas and areas similar to renal cortex (two cases); and (c) nodules quite different from fat, hypointense to the liver (two cases). On T2-weighted images, myelolipomas were slightly hypointense to fat and either hypo- or isointense to the liver. A comparison with the results of CT studies was possible in all cases, and good correlation with determination of the presence and quantity of fat density tissues within the lesions was observed. However, MR imaging did not seem to help in diagnosing adrenal myelolipoma in patients with equivocal CT findings, and needle biopsy is still needed in difficult cases.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

[Ultrasonography and computerized tomography in the diagnosis of renal metastasis].

The US and CT findings of renal metastases are described in a series of 26 patients. US findings were round or oval masses ranging in diameter from 1.5 cm to 8 cm (mean: 4.2 cm); in only 21.2% of cases lesion diameters were less than or equal to 3 cm. In most patients (84.8%) the metastatic lesions were hypo-isoechoic, while in the extant cases they were either mildly hyperechoic or inhomogeneous. CT findings were round masses with variable diameters (1 cm to 8 cm; mean: 2.7 cm); in most cases (86.4%) lesions diameters were less than or equal to 3 cm. The latter finding was in significant disagreement with US results. CT densities were within the soft-tissue range, and always hypodense if compared to normal renal parenchyma in contrast-enhanced scans. Few cases of perirenal metastases were observed. US sensitivity was only 57%, much lower than that of CT; the latter method yielded no false negatives. CT showed metastatic lesions in patients with normal US findings; in 2 cases a greater number of lesions was detected with CT than with US. Our results are in substantial agreement with literature data, as far as US and CT findings are concerned; however, a lower incidence of bilateral cases was observed in our series than in previous reports. Our results support the primary role of CT in the detection of renal metastases thanks to its high sensitivity and to its allowing the simultaneous evaluation of other organs.

Humans↗