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A Tartaro

Publications and source records attributed to A Tartaro.

34 records · Page 2Linked to original sources
PubMed1993

[2D TOF angio-MR of the thoraco-abdominal aorta. Technique and clinical applications].

The diagnostic role of Magnetic Resonance Angiography (MRA) was investigated in the study of the thoracic and abdominal aorta. Thirty-two patients with different conditions were examined: the thoracic aorta was affected in 7 cases (3 aneurysms, 2 dissections, 2 tumors) and the abdominal aorta in 25 cases (21 aneurysms, 3 stenoses and 1 dissection). Moreover, 2 kinkings and 1 dextroposition of the thoracic aorta were observed as occasional findings, together with 15 abdominal aorta kinking cases. A 1.5-T superconductive magnet (Magnetom, Siemens) with circular polarization body coil and the 2D TOF (FL 18 degrees, TR 30 ms, TE 10 ms, ST 5 mm, 1-mm overlap) technique were used. The images acquired on the coronal and sagittal or parasagittal planes were rotated from -45 degrees to 45 degrees and from 60 degrees to 120 degrees during post-processing, according to MIP. Digital angiography was the gold standard in all cases, angiography and CT were the gold standards for aneurysms, and surgery for the lesions reaching the thoracic aorta. The 2D TOF technique allowed excellent visualization of both the thoracic and the abdominal aorta. In thoracic aorta conditions, MRA always identified aneurysms and assessed their relationship to epiaortic branchings. Moreover, MRA identified 2 cases of thoracic aorta dissection. In one case (1/2) MRA failed to depict aortic wall infiltration by tumor. In 21 abdominal aorta aneurysms, MRA always correctly demonstrated both the extent of the aneurysm and its relationships to renal and iliac arteries. Moreover, the thrombotic aneurysmal component was demonstrated, together with left renal vein course, which was retroaortic in 4 cases. Abnormal course, stenoses (2 cases) and dissection of the abdominal aorta were always identified by MRA.

Aorta, Abdominal↗
PubMed1992

[Magnetic resonance angiography with gadolinium (Gd-DTPA) versus baseline magnetic resonance angiography in the study of the intracranial circulation].

The authors evaluated the role of GdDTPA in magnetic resonance angiography (MRA) of intracranial vessels. Fifteen patients affected with different conditions underwent MRA of intracranial vessels before and after paramagnetic contrast medium infusion. A superconductive 1.5-T magnet (Magnetom Siemens) was used, and a head circular coil, together with the 3DFT TOF technique. The enhanced exam was performed following the infusion of 0.2 ml/kg of GdDTPA in about 2 minutes, with simultaneous MRA image acquisition. To compare enhanced with unenhanced images relative to signal intensity, the signal increase at the basilar artery and carotid sinus was studied, together with signal-to-noise (S/N) ratio and spatial resolution. During acquisition, enhanced MRA images at the basilar artery showed a mean intensity value of 423.8 +/- 33.2 vs 357.8 +/- 53.2 of unenhanced scans; a statistically significant difference (p < 0.05; p < 0.01) was observed in favor of enhanced images. At the carotid sinus, enhanced MRA showed 184.5 +/- 28.4 mean intensity value vs 190.5 +/- 19.8 of unenhanced exams; no statistically significant difference was observed (p < 0.05; p < 0.01) in favor of unenhanced exams. At the basilar artery the S/N ratio of baseline exams was 1.9 vs 2.2 for enhanced scans; at the carotid sinus S/N ratio was 2.4 (unenhanced) vs 2.3 (enhanced). Thus, MRA allowed better visualization of peripheral branches of arterial (95.6%) and venous vessels, which unenhanced scans always failed to depict; on the other hand, enhanced images exhibited poorer definition of arterial vessels which were never isolated from the background. The simultaneous visualization of arterial and venous vessels, of choroid plexus and mucosae, affect the quality of enhanced angiograms. At present, GdDTPA is the sole contrast medium suitable for MRA intracranial vessels even though, due to its pharmacokinetic features, it is not the optimum medium.

Adult↗
PubMed1992

[Magnetic resonance venogram of the intracranial circulation. Technique, anatomy, indications].

The authors standardized the MR-venography technique in 50 patients for the study of intracranial venous circulation and identified, for each vessel and district, the best acquisitions and rotations. The possible diagnostic applications of MR-angiography were also evaluated. The examinations were performed with a 1.5-T superconductive magnet (Magnetom, Siemens) and linear head coil. Fifty subjects were examined--40 healthy volunteers, 5 patients affected with multiple sclerosis (MS) and 5 patients with pathologic conditions of intracranial venous circulation. The 40 volunteers were studied with FISP 2D techniques; in 10 of them the images were acquired on the coronal plane, in 10 on the sagittal plane, in 10 on the axial plane, and in 10 on the axial plane after a 90 degrees saturation pulse to obtain saturation of the arterial signal. The FISP 3D sequence acquired on the axial plane and after i.v. gadolinium administration was used in the study of the 5 patients affected with MS. In the post-processing all the acquired images were rotated on the axial (z), sagittal (x), and coronal (y) axes, from 0 degrees to 180 degrees with a 15 degrees step. Data correlation showed that the veins of the postero-superior group were well visualized with 2D sequences on the sagittal plane and rotated, in the post-processing, on the z axis 0 degrees-180 degrees and on the coronal axis from -45 degrees to 45 degrees. The veins of the antero-inferior group were clearly demonstrated with 2D sequences acquired on the axial plane and after arterial saturation, rotated in the post-processing on the sagittal and coronal axes from -45 degrees to 45 degrees. Small veins--i.e., veins of the scalp, diploic and emissary veins, and inferior sagittal sinus--were well visualized with 2D sequences acquired on the coronal plane an rotated during post-processing on the z and x axes 0 degrees-180 degrees following i.v. injection of gadolinium. MR-venography is a new technique which can be useful to answer such specific diagnostic questions as the staging of brain neoplasm contiguous to intracranial venous vessels, the study of arteriovenous malformations and thrombosis on intracranial venous sinuses, as it has been demonstrated in 5 pathologic cases.

Cerebral Veins↗
PubMed1991

[Cerebrovascular pathology. Comparison of magnetic resonance and magnetic resonance angiography].

After making the visualization of the intracranial circulation possible without contrast media, the radiologist is now evaluating the diagnostic role of the different techniques of MRA. Attempts are also being made to characterize the main patterns of intracranial vascular diseases. The authors examined, with 3D TOF MRA, 40 patients presenting with 50 vascular lesions on MRI scans. Twenty of 40 patients were also studied with angiography. Seventeen aneurysms were detected, together with 3 stenoses of the cerebral arteries, 13 arteriovenous malformations, 12 dolichobasilar arteries, 3 postoperative and 2 post-embolization controls. MRI was performed with a superconductive magnet (1.5 T), a dedicated coil and gradient-echo 3D TOF FT sequences. The refocused sequence for flux, FISP 3DFT, required the following parameters: TR = 0.04 s, TE = 10 ms, flip angle = 15 degrees, 256 x 256 matrix, 1 acquisition. The 64-80 mm volume along the axial plane was divided so that an actual 1-mm thickness was excited. In post-processing, the maximum-intensity projection was employed on the axial plane 0 degrees-90 degrees (15 degrees interval). In the various conditions, the results obtained with MRA were correlated and compared with MRI findings. MRA provided useful additional information in 27.4% of cases in the study of aneurysms, arteriovenous malformations, vascular occlusion and dolichobasilar arteries, as well as in the follow-up of these lesions. MRA is currently suggested in the evaluation of cerebral circulation and is considered a complementary technique to MRI. MRA is also to be used preliminary to angiography.

Arteriovenous Malformations↗
PubMed1990

Reduced temporal lobe areas in schizophrenia: preliminary evidences from a controlled multiplanar magnetic resonance imaging study.

Seventeen young patients with relapsing schizophrenia and 13 normal controls matched for age, gender, and educational level underwent magnetic resonance imaging (MRI) scans. Three sagittal, eight axial, and seven coronal images were obtained for all subjects. Schizophrenic patients showed a reduction of brain tissue in the temporal lobes. Among the several brain structures identified, left temporal lobe area, but not ventricular brain ratio (VBR), discriminated between the two groups. As VBR has been reported to be increased in the more severe forms of schizophrenia, temporal lobe abnormalities may characterize the less severe cases of schizophrenia.

Adult↗
PubMed1990

[Magnetic resonance angiography of the intracranial vessels. Technique and anatomy].

Fifty volunteers were studied by means of MR angiography of the intracranial vessels, with a 1.5 T Siemens Magnetom. The technical features of the most employed MR angiographic techniques were analyzed. The inflow technique was tested with refocused gradient-echo sequences for the FISP 3DFT flow and a dedicate coil. The study was aimed at evaluating the resolution power of each technique and at identifying the most useful rotations and angles for each chosen vessels. The acquisition volume of the gradient-echo sequence was positioned on the axial plane with sella turcica in the center. TR was set at 0.04 s, TE at 10 ms, and flip angle was 15 degrees. A 256 x 256 matrix was used, and an 80-mm acquisition volume, with 64 partitions. The chosen images were rotated on the axial and sagittal planes 0 degrees-180 degrees. The results showed that both rotation planes and their relative angles allow the visualization of all the vessels. To reduce post-processing time, with immediate availability of computer keyboard, a standardization is suggested with 0 degrees-180 degrees rotations on the axial plane, with 15 degrees interval and 0 degrees-45 degrees rotations on the sagittal plane, with 15 degrees interval. The main limitation of this method is its spatial resolution, which was 1.2 mm in rotations and acquisitions on the axial plane and 1 mm in acquisitions on the axial plane rotated on the sagittal plane.

Adult↗
PubMed1990

[Usefulness and limitations of neuroradiologic tests (CT, US, MRI) in periventricular leukomalacia].

Sixteen young patients, with clinical and radiological signs of periventricular leukomalacia (PVL), were investigated with MR imaging. Twelve of them were investigated with US in the perinatal period. The extant 4 patients, older than the others, had a clinical history of PVL. US scans were capable of yielding precise information about the anatomical features of PVL in both the acute and the middle phases. The lesions appeared as hyperechoic areas which subsequently turned to anechoic cavities. MR imaging and CT scans did not present any particular advantage over US scans in the acute phase, but they did detect periventricular damage when the patient was 6-7 months old. MR imaging was superior to CT in detecting the delayed myelination of white matter. Inversion-recovery sequences gave more anatomical details to distinguish normal from abnormal white matter. Spin-echo proton-density images detected periventricular gliosis, which appeared as persistent hyperintense areas. CT might be useful in the acute phase, after US detection of hyperechoic intraparenchymal areas, for it allowed purely ischemic lesions to be distinguished from hemorrhagic ones.

Adolescent↗
PubMed1989

[Lymphocyte subpopulations in multiple sclerosis (MS). A contribution].

The characterization of peripheral blood T-cell subpopulations in 29 multiple sclerosis (MS) patients is studied. A direct immunofluorescence assay was performed using monoclonal antibodies (OK series) directed to lymphocytes surface antigens. In transverse study, the patients suffering from progressive MS showed T4+ lymphocytes and T4+/T8+ ratio significantly high (p less than 0.05) compared to controls; furthermore T8+ lymphocyte values were low. T3+ lymphocytes were low (p less than 0.05) during the relapse in the MS remitting relapsing patients. A six month follow-up of the patients showed, during relapse, a reduction and, immediately after, a recovery of T3+ and T4+ lymphocyte values; T8+ lymphocytes didn't show remarkable fluctuations.

Adult↗
PubMed1985

Parkinsonism, basal ganglia calcification and epilepsy as late complications of postoperative hypoparathyroidism.

A patient with post-thyroidectomy hypoparathyroidism, basal ganglia calcification, parkinsonism and seizures is reported. The parkinsonism was resistant to levodopa therapy but was not significantly improved by the correction of hypoparathyroidism. Previously reported cases are discussed, as well as the relationship between hypoparathyroidism, calcification of basal ganglia, parkinsonism and epilepsy.

Basal Ganglia Diseases↗
PubMedDate not supplied

The role of magnetic resonance angiography in the diagnosis of subclavian steal.

PURPOSE: To compare magnetic resonance angiography (MRA) with digital angiography for diagnosis of subclavian steal syndrome. METHODS: A comparison study between MRA and digital contrast arteriography was carried out in 10 patients with suspected subclavian steal syndrome. Two of these patients were studied by MRA before and after percutaneous transluminal angioplasty (PTA). MRA was obtained on a 1.5 tesla superconductive magnet with linear head coil using a fast low angle shot (FLASH 2D) sequence in the axial plane as well as a fast imaging with steady state precession (FISP 3D) with velocity compensation gradient echo sequence in the coronal plane. The coronal images were used as source data for the construction of projection images with the use of a maximum-intensity pixel algorithm. The images were rotated from -45 degrees to 45 degrees in 15 degrees steps. RESULTS: All 10 patients had evidence of proximal subclavian artery obstruction and flow reversal in the ipsilateral vertebral artery. On MRA, consistent visualization of the affected vertebral artery in the FLASH 2D sequences and nonvisualization in the FISP 3D sequences was interpreted as an indirect sign of subclavian steal. The subclavian artery obstruction could not be assessed due to field size limits of MRA. CONCLUSION: MRA allows determination of flow reversal in the diagnosis of subclavian steal.

Adult↗
PubMedDate not supplied

[Neoplasms of the glomus caroticum: magnetic resonance angiography versus magnetic resonance].

This work was aimed at investigating the diagnostic role of Magnetic Resonance angiography (MRA) versus spin-echo images in the study of carotid paragangliomas. Ten patients affected with carotid paragangliomas were studied; surgery was the gold standard. MR examinations were performed with a superconductive 1.5 T magnet and a linear head coil. T1-weighted (TR 500 ms, TE 15 ms, 256 x 256 matrix) and T2-weighted (TR 2000 ms, TE 15/90 ms, 256 x 256 matrix) spin-echo sequences were acquired. TOF 3D (flash: FA 25 degrees, TR 30 ms, TE 7 ms) MRA images were acquired; coronal and sagittal images were rotated according to the MIP. Spin-echo images demonstrated the typical "salt and pepper" pattern in all cases. In 6 cases (lesion diameter > 3 cm) the vascular structures of the paragangliomas and carotid dislocation were clearly demonstrated by MRA. MRA also depicted carotid dislocation in all cases. In conclusion, in the evaluation of carotid paragangliomas > 3 cm diameter, MRA yields complementary information on vascular structures and dislocation of carotid vessels to spin-echo MR sequences.

Adult↗
PubMedDate not supplied

[Optimization and diagnostic accuracy of computerized tomography with tridimensional spiral technique in the study of craniostenosis].

INTRODUCTION: Conventional Computed Tomography (CT) with three-dimensional (3D) reconstructions is considered the most complete and accurate imaging modality to diagnose craniosynostosis. However, the introduction of Spiral CT (SCT) opened new possibilities for 3D studies of the skull in pediatric patients with craniosynostosis. The purpose of our study is two fold: first, to optimize the scanning and imaging parameters to obtain diagnostic images in a single spiral scan; second, to assess the diagnostic accuracy of such images in the identification of normal and abnormal cranial vault sutures. MATERIAL AND METHODS: Seventy-eight pediatric patients (age range: 1-35 months; mean: 11.8 months) with craniosynostosis were submitted to SCT of the head. The images were acquired with the following parameters: 3- and 5-mm nominal slice thickness, 5-6 mm/s table feed (pitch 1-2), 165 mAs and 120 kV. Two different algorithms and increases were used for image reconstructions. A first set of images was reconstructed with 2-mm increases and a soft tissue algorithm: these images were used for brain studies and for 3D reconstructions. A second set of slices was reconstructed with 5-mm increases and a bone algorithm to visualize the sutures of the axial plane. The 3D images were processed with the Shaded Surface Display software with threshold values ranging 120-150 HU. All images were acquired with a single spiral scan lasting less than 30 seconds. Two blinded radiologists analyzed the 3D and the planar images independently to evaluate the course and depth of each cranial suture. The sensitivity, specificity and diagnostic accuracy of both 3D and planar SCT images were evaluated. The frequency of artifacts (the Lego effect, boiled egg, pseudoforamina, movement, and chainsaw artifacts) and their influence on the final diagnosis were studied on 3D SCT images. RESULTS: The diagnostic accuracy rates of 3D SCT images, by suture, were: sagittal 90.7%, metopic 100%, left lamboid 90.9%, right lamboid 93.9%, left coronal 85.7%, right coronal 91.1%. The diagnostic accuracy rates of the axial images, by suture, were: sagittal 90.7%, metopic 95.5%, left lamboid 86.4%, right lamboid 90.9%, left coronal 83.7%, right coronal 91.1%. The interobserver agreement on 3D images was: sagittal 91.1%, metopic 100%, left lamboid 88.9%, right lamboid 91.1%, left coronal 88.9%, right coronal 84.4%. The Lego effect artifact was the most frequent one (82%) and affected image evaluation in 6.3% of cases. CONCLUSIONS: Our results prove that 3D SCT is a very accurate technique for identifying normal and abnormal sutures and presents many advantages over conventional 3D CT in the examination of pediatric patients with craniosynostosis. The quality of 3D SCT images was adequate and the artifacts did not affect the final diagnostic yield significantly.

Child, Preschool↗