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Biomedical subjects

N Vasile

Publications and source records attributed to N Vasile.

At least 37 records · Page 2Linked to original sources
PubMed1994

MR imaging in acute infectious cellulitis.

PURPOSE: To describe magnetic resonance (MR) imaging findings in acute infectious cellulitis and assess its value for the diagnosis of severe necrotizing forms. MATERIALS AND METHODS: Spin-echo (SE) T1- and T2-weighted imaging was performed in 36 patients with acute infectious cellulitis. T1-weighted SE images obtained after injection of a paramagnetic contrast agent were also obtained when an abscess was suspected on precontrast images. Sixteen patients underwent surgical débridement, along with fascial and muscle biopsy. RESULTS: Distinct MR imaging features were found in patients with necrotizing soft-tissue infections, that is, hyperintense signal on T2-weighted images at the deep fasciae, poorly defined areas of hyperintense signal on T2-weighted images within muscles, and peripheral enhancement on contrast material-enhanced T1-weighted images. In nonnecrotizing cellulitis, signal intensity abnormalities were seen only in the subcutaneous fat. CONCLUSION: The precise extent of acute cellulitis and the presence of necrotizing soft-tissue infections can be determined with MR imaging, particularly on T2-weighted images.

Abdominal Muscles↗
PubMed1993

Focal nodular hyperplasia of the liver: value of color Doppler US in association with MR imaging.

Seventeen patients with 19 lesions of focal nodular hyperplasia (FNH) underwent prospective examination with color Doppler ultrasound (US) and magnetic resonance (MR) imaging. In 13 lesions, color Doppler US demonstrated central spots with an arterial Doppler spectrum. The frequency shifts ranged from 1.02 to 1.94 kHz (mean, 1.56 kHz). On flow-sensitive unenhanced gradient-echo images, hyperintense central dots were depicted in only five of these 13 lesions. All the MR features of FNH were present in 12 lesions. Among the seven lesions without all of the MR features, central color spots were present with an arterial Doppler spectrum in four lesions. In the remaining three lesions, color Doppler examination demonstrated either peritumoral pulsatile flow (two lesions) or no flow (one lesion). Color Doppler US adds information about the intratumoral flow characteristics of this vascular malformative lesion and appears to be superior to MR imaging in detection of the arterial intratumoral abnormalities.

Adult↗
PubMed1993

Detection of multiple myeloma involving the spine: efficacy of fat-suppression and contrast-enhanced MR imaging.

OBJECTIVE: To determine the efficacy of fat-suppressed sequences and contrast-enhanced MR imaging for the detection of focal spinal lesions caused by multiple myeloma, we obtained MR images in 32 patients with newly diagnosed myeloma who had back pain. SUBJECTS AND METHODS: All patients had biopsy-proved myeloma and had MR imaging at the painful level of the spine. Spin-echo T1-weighted, T2-weighted, and short TI inversion-recovery (STIR) images; dynamic ultrafast low-angle shot (turbo-FLASH) images after IV injection of a bolus of paramagnetic contrast material; and contrast-enhanced T1-weighted images were obtained. We qualitatively compared the signal intensities and contrast enhancement of focal lesions with those of the surrounding vertebral bodies. RESULTS: Multiple lesions were detected in all but two of the 32 patients. On T2-weighted and STIR images, all lesions had homogeneously high signal intensity. On T1-weighted images, the lesions were visible as hypointense areas compared with surrounding bone in all except four patients, in whom the lesions were isointense or hyperintense. All tumor nodules enhanced on turbo-FLASH images obtained in the arterial phase. No additional lesions were seen on STIR or contrast-enhanced images. MR findings resulted in a change in the staging of the disease in one patient and led to prompt treatment in five patients with epidural involvement. CONCLUSION: MR imaging appears to be helpful in detecting spinal involvement in patients with multiple myeloma. The diagnosis of spinal lesions is best achieved by using either fat-suppressed or T2-weighted images. Although myeloma lesions enhanced in all patients, contrast material appears to be of no value for the detection of additional lesions.

Contrast Media↗
PubMed1993

MR appearance of multiple myeloma of the spine before and after treatment.

OBJECTIVE: The aim of this study was to describe the changes in the MR appearance of painful lesions of the spine before and after treatment in 18 patients with multiple myeloma and to correlate these changes with the clinical response to treatment. SUBJECTS AND METHODS: Eighteen patients with multiple myeloma and tumor nodules in the spine had MR imaging of the same site in the spine before and after treatment. Unenhanced T1- and T2-weighted spin-echo images, dynamic ultrafast low-angle shot (turbo-FLASH) images before and after IV bolus injection of paramagnetic contrast material, and contrast-enhanced T1-weighted spin-echo images were obtained. Characteristic signal and contrast enhancement before and after treatment were compared and were correlated with clinical data and the results of immunochemical and pathologic tests. RESULTS: Changes in signal intensity and enhancement of the lesions occurred after treatment in 14 of 18 patients. The characteristics of the lesions after treatment had three patterns: (1) rim enhancement or no enhancement of the lesions, (2) early enhancing lesions associated with other nonenhancing lesions or lesions with rim enhancement, and (3) no change from the enhancement pattern seen before treatment. In 13 of 18 patients, these patterns correlated well with the response to treatment. A discrepancy was observed in five patients. CONCLUSION: The MR appearance of spinal myeloma is different before and after treatment. MR images, particularly contrast-enhanced images, may be helpful in monitoring the response to treatment of focal bone lesions of myeloma.

Combined Modality Therapy↗
PubMed1993

[Role of x-ray computed tomography in the follow-up of the course of Hodgkin's disease].

Fourteen files of patients having had Hodgkin's disease have been analyzed retrospectively to assess the justification of systematic surveillance after complete remission has been achieved. The data of successive CT exams, compared with the findings of clinical and biological studies performed on the same dates, confirm the primordial role of imaging, since computed tomography was predictive for 7 of 18 events (14 relapses and 4 second progressions). The occurrence of subphrenic recurrence in 3 cases for which the initial site was mediastinal leads to discussing the merits of a yearly thoraco-abdomino-pelvic examination during the two years following complete remission.

Adult↗
PubMed1992

Value of CT and sonography in the conservative management of acute splenoportal and superior mesenteric venous thrombosis.

Acute splenoportal and superior mesenteric venous thrombosis were diagnosed on sonography and computed tomography (CT) in six patients. Sonography demonstrated the presence of echoic material filling the involved vessels in all patients. Precontrast CT scans demonstrated an increased, intra luminal density of the clots in four patients with splenoportal thrombosis. However, in two cases of superior mesenteric venous thrombosis, no hyperdensity was observed within the lumens. Nevertheless, the clots were always visualized as low-density regions in the vessel lumens after bolus injection. Intravenous anticoagulant therapy was started immediately after the diagnosis. All patients were evaluated twice a week with sonography and/or CT until recanalization occurred. The patency of the previously involved vessels was assessed from 6 days to 4 weeks after the acute episode (average time of recanalization: 17 days) without development of collateral pathways. It is concluded that, in the absence of clinical signs of a life-threatening process, a conservative management of acute splanchnic thrombosis can be successfully achieved by (1) early diagnosis, (2) efficacious intravenous anticoagulant therapy, (3) careful imaging follow-up of these patients by sonography and/or CT during the acute phase and, finally, (4) by an extensive search for a hypercoagulable state.

Acenocoumarol↗
PubMed1992

Fast magnetic resonance imaging in the evaluation of tumoral obstructions of the inferior vena cava.

A prospective study was conducted on 9 patients with suspected obstruction of the inferior vena cava on ultrasonography, dynamic computerized tomography and/or inferior venacavography during the course of a retroperitonal tumor to assess the value of magnetic resonance imaging with gradient echo sequences. The findings on gradient echo magnetic resonance imaging were compared with the other imaging modalities and surgical or necropsy results. Our results suggest that gradient echo magnetic resonance imaging is the most appropriate imaging modality to diagnose and delineate the extent of inferior vena caval obstruction.

Adult↗
PubMed1992

Clinical and biological analysis of peripheral T-cell lymphomas: a single institution study.

Peripheral T-cell lymphoma (PTCL) accounts for 15-20% of non-Hodgkin's lymphoma in the Western World. Clinical, histopathologic, phenotypic and genotypic data were received from 33 cases of PTCL referred to our institution. The median age order was 50 years, 78% were males, and 18% had a history of a preceding disorder of the lymphoid system. 60% had stage 4 at diagnosis and B symptoms were also present in 60%. The most frequent sites of extranodal involvement were bone marrow (54%), liver (45%) and skin (33%). Twenty-eight of 33 cases were histologically classified according to the Working Formulation (most in the diffuse mixed and large-cell subgroups) and the Kiel updated system. Phenotypic and genotypic studies of malignant cells showed a considerable heterogeneity with respect to the expression of either T-cell receptor (TCR) alpha beta and gamma delta and pan-T differentiation molecules. Of the studied cases 63% expressed TCR-alpha beta. All five patients with PTCL of the TCR-gamma delta subtype had a peculiar extra-nodal presentation. The vast majority of cases expressed an abnormal T-cell phenotype with respect to the expression of pan-T antigens, including the lack of expression of the TCR-associated CD3 molecule in 2 cases. Rearrangements of the TCR beta and/or delta-chain genes showed clonality in 21 of the 23 studied cases. Twenty-five patients were treated with a multiagent chemotherapy regimen with curative intent and the remainder received a less intensive palliative regimen. Only 9 patients achieved CR (8 of whom had received an anthracycline-containing regimen) and the 4-year survival rate was 25%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[X-ray computed tomography of thoracic injuries. Apropos of 40 cases].

On chest radiographs, the precise assessment of thoracic injuries consecutive to blunt trauma is often compromised by the nonspecific appearance of many lesions. Furthermore, significant injuries are frequently overlooked. However, the management of the patients with chest trauma is still often based primarily upon clinical and radiographic findings and Computed Tomography (CT) is often performed secondarily on the basis of unexplained clinical signs or suspected radiographic abnormality. Some authors have reported that CT was a highly sensitive method for detecting thoracic lesions frequently not seen or underestimated on conventional supine chest radiographs. However, the value that these new CT findings could have in the therapeutic management of these patients, have not been systematically investigated to our knowledge, except in a limited series suggesting that the course of critically ill patients could be substantially altered after thoracic CT. In order to estimate the role of early CT in the management of patient care, we report the therapeutic consequences of CT findings in forty patients who we report the therapeutic consequences of CT findings in forty patients who had a thoracic CT within few hours following a chest injury. We showed that early thoracic CT scan in patients with blunt trauma detected significantly more lesions than did chest X-Ray and appreciably modified the treatment modalities in 70% of our patients. We then recommend that all the patients admitted in ICU after chest trauma undergo a thoracic CT scan as soon as possible in order to optimize their treatment modalities.

Adolescent↗
PubMed1992

Asymptomatic renal-vein thrombosis in adult nephrotic syndrome ultrasonography and urinary fibrin-fibrinogen products: a prospective study.

OBJECTIVES: The diagnosis of renal vein thrombosis (RVT), a frequent complication of adult nephrotic syndrome (NS), is generally made by means of invasive methods, i.e. renal venography, venous time of renal arteriography and, more recently, computed tomography (CT). We undertook a prospective study to evaluate the use of Doppler ultrasonography (DUS) and urinary fibrin-fibrinogen degradation products (FDPU) for the diagnosis of asymptomatic RVT. METHODS: Thirty-one adult NS with non proliferative glomerulonephritis were studied. Reference procedures [(selective renal arteriography (n = 18) and renal vein CT (n = 13)] were performed blindly within a few days (48 hours in 17 patients) of renal vein DUS (search for a lack of venous flow) and measurement of FDPU (5 micrograms/min) (in 24 patients). RESULTS: DUS was not interpretable in one patient and positive in nine. Of these 9 patients, RVT was detected by reference methods in only two (sensitivity: 1, specificity: 0.75; positive predictive value: 0.22; negative predictive value: 1). Increased FDPU was observed in 4 patients, 2 of whom had an RVT (sensitivity: 1, specificity: 0.9; positive predictive value: 0.5; negative predictive value: 1). CONCLUSION: We conclude that DUS and FDPU are helpful for screening of RVT in asymptomatic NS patients; their negativity allow further radiological investigations to be avoided while positive results must be confirmed by reference methods.

Adolescent↗
PubMed1991

Value of MR imaging in evaluating focal fatty infiltration of the liver: preliminary study.

Focal fatty infiltration of the liver is a well-known entity that occasionally mimics metastatic disease on ultrasonographic (US) and computed tomographic (CT) scans and requires biopsy for diagnosis. To determine if high-field-strength magnetic resonance (MR) imaging might be useful in the differential diagnosis of the lesions, the authors compared US, CT, and MR findings in three patients with biopsy-proved fatty hepatic lesions. Areas of focal fatty infiltration were hyperechoic on US scans and had low attenuation on CT scans. No mass effect of the lesions on vascular structures or liver contours was observed, particularly on contrast material-enhanced CT scans. For all three patients, MR findings suggested the correct diagnosis by demonstrating focal high signal intensity on spin-echo T1- and T2-weighted images. On the basis of these preliminary findings, it appears that focal fatty infiltration of the liver may be differentiated from metastatic disease by means of high-field-strength MR imaging.

Aged↗
PubMed1991

Focal nodular hyperplasia of the liver: assessment with contrast-enhanced TurboFLASH MR imaging.

Twenty-two patients with 25 cases of focal nodular hyperplasia (FNH) proved with pathologic study were imaged with a TurboFLASH (fast low angle shot) sequence combined with bolus administration of gadolinium tetraazacyclododecanetetraacetic acid (DOTA), spin-echo (SE) T2-weighted sequences, and postcontrast T1-weighted sequences. FNH-liver signal-difference-to-noise ratios were quantified; the features of the central scar were qualitatively analyzed. On SE T2-weighted images, all FNHs were hyperintense; in two cases the central scar exhibited a high signal intensity associated with hypointense areas corresponding to fibrous tissue within the branches of the scar. Unenhanced TurboFLASH images always demonstrated the FNHs as hypointense and always depicted the central scar as a hypointense area within the lesion. After bolus injection, arterial enhancement of FNH was clearly seen, and in 10 of 25 lesions, enhancement within the scar was seen 40-80 seconds after injection. Both unenhanced and enhanced TurboFLASH sequences produced the best signal-difference-to-noise ratios in comparison with T2-weighted images.

Adolescent↗
PubMed1991

Constant-flow insufflation prevents arterial oxygen desaturation during endotracheal suctioning.

In mechanically ventilated patients, disconnection from the ventilator and endotracheal suctioning can induce major arterial oxygen desaturation resulting from apnea, changes in inspired oxygen fraction, and decrease in lung volume. The aim of this study was to test the efficacy of a simple method of delivering oxygen and maintaining lung volume during this process. Our study was conducted in two parts. In the first part, constant-flow insufflation of oxygen (CFI) was used in seven patients ventilated for acute respiratory failure (PaO2/FlO2 = 347 +/- 33 mm Hg) as a means of maintaining arterial oxygenation during apnea and disconnection from the ventilator. CFI was administered via a modified endotracheal tube in which small capillaries allowed delivery of a high-velocity jet flow near the tracheal end of the tube during disconnection from the ventilator. In comparison to apnea alone, CFI prevented a fall in arterial oxygen tension (16 +/- 7 mm Hg during CFI versus 117 +/- 27 during apnea, after 90 s of disconnection in the two situations, p less than 0.001), whereas it did not reduce the development of hypercapnia. The efficacy of CFI resulted both from the injection of oxygen into the trachea and from the maintenance of positive alveolar pressure induced by air entrainment (mean 10.4 +/- 1.1 cm H2O), preventing a fall in lung volume usually occurring after disconnection (+338 +/- 88 ml during CFI versus -344 +/- 64 ml during apnea, p less than 0.01). In the second part of the study CFI was used to prevent arterial oxygen desaturation induced by endotracheal suctioning.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

[Gradient echo sequences in the diagnosis of inferior vena cava thrombosis].

The capability for studying noninvasively vessels has been dramatically improved with the use of gradient echo sequences. Twenty-one patients presenting a suspected inferior vena cava obstruction on cavography underwent MR examination with axial, sagittal and coronal gradient echo images. Eighteen patients were also imaged with ultrasound and/or CT. Gradient echo sequences visualized a thrombus in 19 cases and a normal vein in the remaining 2 cases. The potential MR pitfalls are illustrated and the two cases of false positive on cavography are discussed. Gradient echo sequences allow a fast and performant examination of the vessels.

Adolescent↗
PubMed1990

[Epidermoid cysts of the spleen. Report of 6 cases].

The authors report 6 cases of epidermoid cysts of the spleen. They emphasize the rarity of the lesion, its pathological and clinical features, and describe the abnormalities which can be noted on plain films, ultrasonography and computed tomography.

Adult↗