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L Bonomo

Publications and source records attributed to L Bonomo.

At least 109 records · Page 6Linked to original sources
PubMed1995

[Diagnostic pitfalls in magnetic resonance angiography].

The authors report on their clinical experience with Magnetic Resonance angiography (MRA) pitfalls. January, 1989, to February, 1995, six hundred MRA examinations were performed in different vascular districts, with a 1.5-T superconductive magnet, the time-of-flight (TOF) technique and 2D and 3D acquisitions. Intracranial arteries, epiaortic vessels and renal arteries were studied with FISP 3D sequences; intracranial veins, thoracic vessels, vena cava and pelvic vessels were studied with FISP 2D sequences. Pitfalls were observed in 56 of 600 MRA exams (9.3%). Of 56 pitfalls, 26 (46.4%) were in epiaortic vessels, 15 (26.7%) in intracranial vessels, 6 (10.7%) in renal arteries, 6 (10.7%) in thoracic vessels, 1 (1.7%) in the inferior vena cava and 2 (3.5%) in iliac vessels. Stenoses were overestimated in 21 patients and underestimated in three; 16 patients were misdiagnosed and 16 were false positives. As for cerebral vascular lesions, 5 aneurysms and 7 transverse sinus thromboses were false positives, while 3 lesions were misdiagnosed as venous angiomas. As for 26 MRA exams of thoracic vessels, stenoses were overestimated in 16 patients and underestimated in 10 patients with subclavian steal syndrome, where the left vertebral artery was misinterpreted as occluded. In 6 MRA exams of thoracic vessels, 1 patient was misdiagnosed as having an aneurysm and 5 patients were misdiagnosed as having lung cancer infiltrating aorta and superior vena cava. As for renal vessels, 2 normal renal arteries were misdiagnosed as false positives and 4 stenoses were overestimated. In the inferior vena cava, a partial agenesis was misinterpreted as thrombosis. In 2 MRA exams of iliac vessels, a stenosis and a thrombosis were misinterpreted as false positives. Our experience suggests that MRA pitfalls are caused by the incorrect use of the various techniques. The pitfalls we observed can be classified as caused by three types of artifacts: saturation, turbulence and paramagnetic substance artifacts.

Diagnostic Errors↗
PubMed1994

Anti-idiotypes against antiphospholipid antibodies are present in normal polyspecific immunoglobulins for therapeutic use.

In the present study we found that antiphospholipid activity in sera from patients with anticardiolipin antibodies was inhibited in vitro by therapeutic polyspecific normal immunoglobulins (IVIg). In fact, F(ab')2 fragments from IVIg (IVIg-F(ab')2) inhibited the binding of anticardiolipin antibodies to the corresponding antigen in a dose-dependent fashion, thus suggesting that the interaction between IVIg-F(ab')2 and anticardiolipin antibodies occurred within or near the antigen combining site. The maximal inhibition ranged from 35.25 +/- 5.56 to 64 +/- 5.48%. In addition, patients' IgG containing antiphospholipid activity specifically bound insolubilized IVIg-F(ab')2, as assessed by enzyme-linked immunosorbent assay (ELISA). These results indicate that IVIg obtained from a large pool of normal donors contain anti-idiotypic antibodies directed against idiotypes located on antiphospholipid antibodies. Moreover, our observations suggest that the reported favourable effect of high dose infusion of IVIg in patients with recurrent abortions due to antiphospholipid antibodies may depend, at least in part on inhibition of the binding of such autoantibodies to the corresponding antigens (s) and/or inactivation of idiotype bearing B cell clones.

Abortion, Habitual↗
PubMed1994

Magnetic resonance angiography of the left renal vein.

The authors evaluated magnetic resonance angiography (MRA) as a possible diagnostic method to image the left renal vein. Twenty-five patients with abdominal aortic aneurysm underwent both plain and contrast-enhanced CT, as well as two-dimensional (2D) sequential time of flight (TOF) MRA. MRA images were evaluated on the basis of the results of CT, taken as the "gold standard" for vessel demonstration. MRA was performed with a 1.5 T superconductive magnet (Magnetom), fast imaging with steady-state free precession (FISP) 2D sequence (TR 40 ms, TE 10 ms, FA 18 degrees). Images were acquired in breath-hold on the coronal and sagittal plane and reconstructed according to maximum intensity projection (MIP) and targeted-MIP techniques. MRA images acquired on the sagittal plane correctly showed the retroaortic course on the left renal v. in six cases. On the coronal plane, targeted-MIP reconstructions for the course of the left renal v. correctly detected its outlet at the level of the inferior vena cava in five cases and of the left iliac v. in one case. MRA appears to be a promising noninvasive vascular imaging technique capable of correctly detecting the course and the outlet of the left renal v. We particularly noticed that the left renal v. can be imaged in a few seconds by using only one scout view with 2D sequential TOF technique on the sagittal plane at the level of the abdominal aorta.

Aged↗
PubMed1994

Comparative effects of arginine and other amino acid deprivation on in vitro expression of lymphocyte activation markers.

Enteral or parenteral arginine supplementation enhances lymphocyte activation after mitogenic stimulation, in rats and humans. Arginine deprivation in culture media is associated with a reduction of lymphocyte activation; this effect, however, has not yet been proven to be specific for arginine. This study was designed to evaluate the specificity of arginine deprivation from culture media on the reduction of in vitro lymphocyte activation. Peripheral blood mononuclear cells, obtained from 11 healthy volunteers, were cultured in RPMI 1640, selectively deprived of single amino acids (i.e. arginine, phenylalanine, leucine, methionine, and threonine) and supplemented with phytohemagglutinin (PHA). The expression of interleukin-2 receptor and transferrin receptor was evaluated by cytometric analysis; the levels of soluble IL-2 receptor were determined by immuno-enzymatic assay. Results were compared with those obtained by culturing cells in non-deprived, RPMI 1640 medium. The expression of transferrin and IL-2 receptor, as well as the levels of IL-2 soluble receptor, were significantly reduced in all deprived media irrespective of the lacking amino acid. These results suggest that the reduction of in vitro lymphocyte activation is not an arginine specific effect. Therefore, the known enhancement of immune response, following arginine supplementation in vivo, is likely to involve a more complex series of events.

Journal Article↗
PubMed1994

Spiral CT of the mediastinum: optimization of contrast medium use.

Spiral computed tomography (CT) allows very satisfactory temporal resolution for the detection and analysis of changes in contrast medium density, so that volumes of contrast material smaller than those recommended for conventional CT can be used. The present double-blind, parallel group study was designed to compare image quality and diagnostic efficacy obtained with two different iodine strengths (200 and 300 mgI/ml) and two different flow rates (2 and 3 ml/s) of a fixed volume (70 ml) of iomeprol in adult consenting patients requiring spiral CT of the mediastinum. Imaging was performed during suspended respiration and, a 15-s delay to scan. Spiral CT was initiated 1 cm above the aortic arch and continued inferiorly for 24 cm in all patients. Two independent readers blindly graded image quality, opacification of the superior vena cava, thoracic aorta and pulmonary arteries, and overall diagnostic quality of the CT examination. CT density measurements were performed over the level of the aortic arch, left and right pulmonary arteries, left atrium, and descending aorta. Opacification of the mediastinal vessels was better in the patients injected at 3 ml/s flow rate and was independent of the iodine strength used, except in the case of the thoracic aorta, which was better opacified by injecting iomeprol 300 mgI/ml at 3 ml/s. The highest diagnostic efficacy of the spiral CT examination was obtained with iomeprol 300 mgI/ml at 3 ml/s infusion rate, which seems to represent the administration scheme of choice.

Adult↗
PubMed1994

Anti-cardiolipin antibodies in autoimmune thyroid diseases.

OBJECTIVE: In recent years anti-phospholipid antibodies have gained much attention since they are frequently associated with thrombosis, recurrent abortion, and thrombocytopenia. Besides disease-specific autoantibodies, other autoantibodies reactive with both organ and non-organ specific autoantigens have been found in patients with autoimmune thyroid diseases. Therefore the objective of this study was to evaluate the presence and significance of anti-phospholipid antibodies in untreated patients with different forms of autoimmune thyroid diseases. PATIENTS AND METHODS: Thirty-one patients (26 females, five males; mean age 42.5 years) affected by different autoimmune thyroid diseases were studied. Fourteen patients were affected by Graves' disease, eight by silent thyroiditis, five by Hashimoto's thyroiditis. Four patients with Graves' disease in remission were also evaluated. Anti-cardiolipin antibodies were detected by enzyme linked immunosorbent assay. In five Graves' disease patients anti-cardiolipin antibodies were evaluated before and after 3 months of therapy with methimazole. RESULTS: Seventeen out of 31 patients were positive for IgG and/or IgM anti-cardiolipin antibodies, the highest levels occurring in three Graves' disease patients with severe thyrotoxicosis. In four of five Graves' patients evaluated before and after methimazole therapy, anticardiolipin antibodies decreased following treatment. None of the patients with increased IgG and/or IgM anticardiolipin antibodies showed clinical manifestations of the anti-phospholipid syndrome during our observation which ranged from 1 to 5 years. CONCLUSIONS: Our results showed an increased incidence of anti-cardiolipin antibodies in patients affected by autoimmune thyroid diseases. However, these autoantibodies seem merely to represent a non-specific marker of immune dysregulation.

Adult↗
PubMed1994

[Artifacts in magnetic resonance angiography].

UNLABELLED: This study was aimed at assessing and classifying the incidence of Magnetic Resonance Angiography (MRA) artifacts using the 2D and 3D time-of-flight (TOF) technique. MATERIALS AND METHODS: from 300 MRA examinations performed January 1991 through April 1993, we selected the first 10 examinations for each vascular region which exhibited an artifact. Many kinds of artifacts were considered, i.e., hardware, sequence, magnetic susceptibility, patient and maximum intensity projection (MIP) artifacts. A superconductive 1.5-T magnet (Magnetom, Siemens) was used, with 2D and 3D TOF acquisitions. RESULTS: the quantitative analysis of artifact frequency showed that in the intracranial vessels (2D and 3D TOF sequences) the most common artifacts are saturation (30%) and magnetic susceptibility (30%) artifacts. As for neck vessels (3D TOF sequences), turbulence (40%) and lack of inclusion (30%) artifacts are the most common ones. In thoracic vessels (2D TOF sequences), MIP (50%) and ghost (30%) artifacts are the most common ones, while in the abdominal aorta (2D TOF sequences) magnetic susceptibility (20%), voluntary movement (20%), peristalsis (20%) and MIP (20%) artifacts occurred most frequently. Saturation (30%) and respiratory movement (30%) artifacts were the most common ones in the study of the renal arteries (3D TOF sequences), while MIP artifacts prevailed (40%) in the inferior vena cava (2D TOF sequences). Finally, MIP (40%) and patient movement (30%) artifacts were the most frequent ones in the study of the lower limbs (2 TOF sequences). CONCLUSIONS: in 2D and 3D TOF studies, being familiar with artifacts and their physical principles helps avoid image misinterpretation so that, if no technical means can prevent an artifact from occurring, at least it will not become a diagnostic pitfall.

Artifacts↗
PubMed1994

[Anesthesiological problems in magnetic resonance].

A prospective study was carried out on 68 patients examined with Magnetic Resonance Imaging (MRI) under general anesthesia. Mean patients age was 10 years (range: 9 days to 77 years). MRI was performed with a 1.5 T superconductive magnet and different anatomical regions were studied: the brain in 63 cases, the lumbar spine in 3, the cervical spine in 1 and finally the upper abdomen in 1 patient. The patients 0-10 years old were anesthetized with isoflurane, while those 11-77 years old were given i.v. propofol and isoflurane. Severe complications occurred in 2 patients only (3%): a 3-year-old child presented respiratory depression and a 21-year-old man had a bronchospasm. Minor complications occurred in 5 more patients. Image quality was excellent in 75% of cases, while few movement artifacts were observed in the extant 25%. To conclude, isoflurane anesthesia is a safe, effective and efficient type of sedation for the patients to be submitted to MRI which can be used also on an outpatient basis.

Adolescent↗
PubMed1994

Monoclonal expansion of immunoglobulin not-secreting CD5+ CD11c+ CD38+ B-cells in a rare case of chronic lymphoplasmacytoid leukaemia.

We present the clinical and immunological features of a rare case of chronic lymphoid leukaemia with lymphoplasmacytoid morphology. The patient was first admitted suffering from weakness, pallor, dyspnoea, marked splenomegaly, hepatomegaly and systemic lymphadenopathy and panhypogammaglobulinaemia. White blood cell count revealed important leukocytosis (220 x 10(9) WBC/l) with 2% neutrophils and 98% lymphoid cells showing lymphoplasmacytoid features, while lymphoid cells of identical morphology severely infiltrated the bone marrow and lymph nodes. The disease, initially controlled by non aggressive chemotherapy over a period of 30 months, later evolved to a clinical and haematological picture suggestive of Richter's syndrome. Immunophenotyping of the leukaemic cells demonstrated a monoclonal expansion of B-cells bearing surface markers of typical CLL (CD5, CD19, CD20, CD21, CD22, CD23, CD24, CD40 and low density IgM+IgD/kappa) and also the CD11c and CD38 antigens. A proportion of these cells expressed activation markers (CD25, CD69 and CD71). Following in vitro activation with TPA or PWM, the cells responded by weak incorporation of 3H-TdR but failed to secrete immunoglobulins. These findings confirm the broad morphological, phenotypical and clinical spectrum of chronic lymphoid leukaemias.

Antibodies, Monoclonal↗
PubMed1994

[Comparative evaluation of 2 non-ionic contrast media, iopentol (350 mgI/ml) and iopamidol (370 mgI/ml) in coronary angiography].

This randomized double-blind comparative study was designed to investigate the safety and efficacy of a new nonionic monomeric contrast agent, Iopentol 350 mgI/ml, versus a nonionic monomeric contrast agent currently used, Iopamidol 370 mgI/ml, in cardioangiography. Blood pressure, heart rate, end-diastolic left ventricular and mean aortic pressure, ECG, adverse reactions and discomfort were the safety variables recorded; technical adequacy and diagnostic yield were the efficacy variables recorded. A hundred patients entered the trial and were subdivided into two groups of 50 patients each; all of them were included in the safety and efficacy assessments. Demographic data, general and background characteristics and procedural data were comparable in the two treatment groups. No significant difference in efficacy was observed between the two groups: diagnostic yield was optimal in 90% of the patients in the Iopentol group and in 88% of the patients in the Iopamidol group. Systolic blood pressure 30 min. after the examination showed, in both groups, a slight but statistically significant reduction relative to baseline values (-3.48 mmHg and -3.85 mmHg in the Iopentol and in the Iopamidol group, respectively), while no significant reduction was observed in diastolic blood pressure. A statistically but not clinically significant decrease in heart rate was observed in the Iopamidol group 30 min. after the examination (-5.05%), while this variable remained practically the same in the Iopentol group (-0.58%). No difference was found between the two groups relative to the incidence of discomfort following the injection. Other adverse reactions were experienced by 7 patients in the Iopentol group and by 9 patients in the Iopamidol group: they all promptly recovered after medical treatment, with no sequelae. All but one event in the Iopamidol group (chest and abdominal pain with ECG changes) were mild to moderate and mainly related to the procedure and to the underlying disease. In conclusion, both contrast agents are safe and effective for use in cardioangiography.

Contrast Media↗
PubMed1994

[Aneurysm of the abdominal aorta. Angiography with magnetic resonance versus color Doppler ultrasonography].

This prospective study was aimed at comparing the diagnostic accuracy of Magnetic Resonance Angiography (MRA) with that of color-Doppler ultrasonography (color-Doppler US) in the detection and assessment of abdominal aortic aneurysms. Twenty patients with abdominal aortic aneurysms underwent MRA, color-Doppler US, digital subtraction angiography (DSA) and Computed Tomography (CT) on three consecutive days. Fourteen patients underwent surgical repair of the aneurysm. MRA and color-Doppler findings were compared with DSA, surgical and pathologic findings, which were considered as the gold standard. In the 6 patients who refused surgery, CT and DSA were considered the gold standard. MRA always correctly assessed the size and site of the aneurysm, the involvement of the renal and common iliac arteries, the retroarotic course of the left renal vein, the thrombotic component and calcifications. Color-Doppler US always correctly assessed the size and site of the aneurysm, the thrombotic component and calcifications and the involvement of the iliac arteries. In one case color-Doppler US failed to demonstrate the involvement of the renal arteries and the retroaortic course of the left renal vein. Our preliminary results suggest MRA as the best non-invasive technique to study abdominal aortic aneurysms.

Aged↗
PubMed1994

[Still's disease in the adult].

The adult Still's disease (ASD) is an uncommon inflammatory systemic disorder which affects the young adult. It is characterized by high spiking fever, vanishing rash, oligopolyarthritis, neutrophilic leucocytosis, negative titers for rheumatoid factor and antinuclear antibodies. Polyserositis, sore throat, uveitis are sometimes present and in one third of the cases it is possible to find hepato-splenomegaly with lymph node enlargement. G. Still first described the disease in child, in 1897, and in the adult it was recognized as a nosologic entity more than 70 years later. The ASD diagnosis is difficult and it is possible after the exclusion of many other diseases. Clinical manifestation are all nonspecific. In particular the presence of adenopathy, hepato-splenomegaly may suggest the possibility of a malignant lymphoma. Important exclusions include many other diseases such as the rheumatic fever, periodic fever, Lyme disease. At the same time a probable diagnosis of ASD should be considered in all the cases of high fever with rash, arthritis, neutrophilic leucocytosis or in the cases of fever of unknown origin (FUO). The prognosis is considered overall benign. The disease is usually sensible to salicylate treatment, even but the association with corticosteroids or, sometimes, with cytotoxic therapy is often required.

Adult↗
PubMed1994

[The superior and inferior venae cavae: angiography by TOF 2D magnetic resonance versus spin-echo sequences].

This work was aimed at assessing the usefulness of magnetic resonance angiography (MRA) in the investigation and diagnosis of vena cava conditions. Forty-five subjects that is 20 volunteers and 25 patients, were examined with MRA using a 1.5 T superconductive system (SE and angiography pulse sequences). In the 25 patients, 8 cases of thrombosis were diagnosed, together with 4 cases of suspected tumor spread into either the superior or the inferior vena cava, 2 cases of inferior vena cava agenesis, 5 cases of retroaortic left renal vein and 5 cases of abdominal aortic aneurysm. MRA was performed with the 2D time-of-flight (TOF) technique (FA 18 degrees, TR 30-40 ms, TE 10 ms); the images were acquired on the coronal, sagittal and axial planes with and without presaturation pulse and rotated in the post-processing according to the maximum intensity projection. In all volunteers MRA identified jugular veins, subclavian veins, anonymous veins, superior vena cava, inferior vena cava and common iliac veins. The main limitation of MRA was its spatial resolution. MRA proved to be less accurate than SE sequences in the assessment of tumor spread. As for thrombotic conditions, MRA provided useful additional information and is therefore considered a complementary technique to SE MRI. As for venous anomalies (double inferior vena cava, vena cava agenesis and retroaortic left renal vein) and in the study of the relationships with abdominal aortic aneurysms, MRA proved to be the more accurate of the two techniques.

Adult↗
PubMed1994

[Renal arteries: angiography with TOF 3D magnetic resonance with and without contrast media (Gd-DTPA)].

This work was aimed at investigating the value of Gd-DTPA to demonstrate distal renal artery branches with 3D TOF Magnetic Resonance angiography (MRA). Ten volunteers and two patients with proximal-distal renal artery stenoses were studied with MRA; all subjects were studied before and after Gd-DTPA. MRA was performed with a 1.5-T superconductive magnet (Magnetom Siemens); the FISP 3D sequence was used with the following setting: FA 25 degrees, TR 40 ms, TE 6 ms, slice thickness 64 mm with 64 partitions and MA 256 x 256. This setting was not changed from pre- to post-contrast scans. The images acquired on the z axis were rotated, according to the MIP, on the axial and the sagittal axes, from 0 degrees to 180 degrees, with a 15 degrees step. 0.2 ml/kg of Gd-DTPA were injected as bolus during 3D acquisitions; the injection was started half-way through acquisition. To evaluate and compare pre- and post-contrast MRA images, the signal-to-noise (S/N) ratio and the demonstration of the various renal artery segments were studied. Average S/N ratio was 2.3 in the right renal artery and 2.1 in the left renal artery on pre-contrast MRA images, while it was 0.9 in the left renal artery and 0.8 in the right renal artery on post-contrast MRA images. These differences were statistically significant (p < 0.01). As for the demonstration of the distal segments and of the bifurcations, enhanced MRA was no better than unenhanced MRA. As for the demonstration of distal segment stenoses, enhanced MRA proved no better than unenhanced MRA in both patients. To conclude, in our experience MRA after Gd-DTPA failed to allow the systematic demonstration of the distal segments and of the bifurcations of the renal arteries.

Adult↗
PubMed1994

[Reproducibility of Doppler ultrasonography in the study of hepatic blood flow].

The reproducibility of hepatic blood flow measurement with pulsed Doppler US was assessed in 6 healthy volunteers. All subjects underwent two different study sessions and were examined by three different operators after overnight fasting. Each operator was blind to his measurements. Hepatic arterial and portal venous blood flow and hepatic arterial maximum velocity were measured; resistive index (RI), pulsatility index (PI) and hepatic perfusion index (HPI) were calculated. Each measurement was repeated three times per session. The data from repeated measurements were analyzed with the analysis of variance (ANOVA) method to assess the intra- and intersubject variations for each variable. The Scheffe test was used to evaluate intra- and interobserver variations. Significant differences among the 6 examined subjects were found for all the variables measured, except for hepatic arterial maximum velocity. The same subject exhibited significant differences in mean velocity of the main portal vein trunk and of its right branch, in maximum hepatic arterial velocity, RI, portal vein section area and blood flow. No significant interobserver variation was observed in the same session and no intraobserver variation detected for all the measurements performed in different sessions. Thus, we conclude that pulsed Doppler US is a repeatable method for measuring hepatic blood flow and may therefore be useful to detect changes in hepatic perfusion.

Analysis of Variance↗
PubMed1994

[Color Doppler ultrasonography in the identification and characterization of secondary focal lesions of the liver].

This study was aimed at assessing the potentials of color Doppler US in the detection of hepatic metastases by measuring changes in hepatic perfusion. Color-Doppler US was performed on 40 patients with multiple metastatic lesions (mean theta: 3 cm). In each patient both smaller and bigger lesions were studied--80 lesions on the whole. Differences in flow distribution (peritumoral or intratumoral) and the highest systolic peak flow velocity were investigated on color Doppler US scans. Hepatic arterial and portal venous blood flow measured in 40 patients with hepatic metastases were compared with those in 40 healthy controls. The two groups were homogeneous relative to age, sex, height and weight. The ratio of hepatic arterial to total liver blood flow (Doppler perfusion index, DPI) and the ratio of hepatic arterial to portal venous blood flow (Doppler flow ratio, DFR) were calculated. Color flow US scans were obtained in 56 of 80 metastatic lesions. We observed peritumoral flow in 76% of the lesions, intratumoral flow in 6% and mixed peritumoral and intratumoral flow in 18% of cases. The DPI and DFR values were significantly higher in the patients with liver metastases than in the control group. The changes in DPI and DFR resulted from an increase in hepatic arterial flow; no changes in portal venous blood flow were observed. These results suggest that Doppler measurements of hemodynamic hepatic changes may be of great value for the earlier detection of hepatic metastases.

Aged↗
PubMed1994

Magnetic resonance angiography compared with basic magnetic resonance in intracranial vascular diseases.

The diagnostic value of magnetic resonance angiography (MR-Angio) in the study of intracranial vascular diseases was compared with that of basic magnetic resonance (MR) in 35 patients presenting with a total of 45 pathologies (13 vascular malformations, 17 aneurysms, 3 vascular stenoses, all also examined by standard angiography, and 12 cases of dolichobasilar artery). A joint reading of the results was carried out by two radiologists who evaluated the basic MR and MR-Angio separately and thereafter filled in a fixed-choice answer form. In the author's opinion, MR-Angio may be considered a complementary technique to basic MR, offering a greater capacity for identification and characterization of these intracranial lesions. In vascular malformations and aneurysms, MR-Angio may be performed as a preliminary to digital subtraction angiography.

Aneurysm↗