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Biomedical subjects

M Mascalchi

Publications and source records attributed to M Mascalchi.

At least 55 records · Page 3Linked to original sources
PubMed1998

Posterior spinal artery infarct.

Acute medullary syndrome developed in a patient in whom glue had been inadvertently injected into the right posterior radiculomedullary artery during endovascular occlusion of a spinal dural arteriovenous fistula at T-11. MR imaging 40 days after the procedure showed signal changes and contrast enhancement in the posterior and right lateral column at T10-11. Circumscribed signal changes in the same areas without contrast enhancement were seen 4 months later. MR imaging was able to show this posterior spinal artery infarct.

Aged↗
PubMed1998

[Hematomyelia complicating a spinal dural arteriovenous fistula. Report of a case].

We report a case of hematomyelia which led to sudden onset complete paraplegia in a 74-year-old man. Hematomyelia revealed a spinal dural arteriovenous fistula at level T8-T9. Spinal hemorrhage was observed in contact with a round-shaped aneurysmal like ectasia which undoubtedly ruptured. Treatment was embolization. Spinal atrophy followed and MRI one year after embolisation visualized the involution of the pathological vessels. We discuss the pathophysiology of this hemorrhagic accident and specific anomalies of the drainage veins in these malformations.

Aged↗
PubMed1997

Gaze-evoked amaurosis heralding orbital angiomyoma. Case report.

The unusual case of a patient presenting with gaze-evoked amaurosis as an early and isolated sign of orbital angiomyoma is reported. Computed tomography or magnetic resonance of the orbits need to be expeditiously performed in patients with gaze-evoked amaurosis in order to identify or rule out the possible presence of an underlying tumor.

Angiomyoma↗
PubMed1997

MRI and MR angiography of vertebral artery dissection.

A review of 4,500 angiograms yielded 11 patients with dissection of the vertebral arteries who had MRI and (in 4 patients) MR angiography (MRA) in the acute phase of stroke. One patient with incidental discovery at arteriography of asymptomatic vertebral artery dissection and two patients with acute strokes with MRI and MRA findings consistent with vertebral artery dissection were included. Dissection occurred after neck trauma or chiropractic manipulation in 4 patients and was spontaneous in 10. Dissection involved the extracranial vertebral artery in 9 patients, the extra-intracranial junction in 1, and the intracranial artery in 4. MRI demonstrated infarcts in the brain stem, cerebellum, thalamus or temporo-occipital regions in 7 patients with extra- or extra-intracranial dissections and a solitary lateral medullary infarct in 4 patients (3 with intracranial and 1 with extra-intracranial dissection). In 2 patients no brain abnormality related to vertebral artery dissection was found and in one MRI did not show subarachnoid haemorrhage revealed by CT. Intramural dissecting haematoma appeared as crescentic or rounded high signal on T1-weighted images in 10 patients examined 3-20 days after the onset of symptoms. The abnormal vessel stood out in the low signal cerebrospinal fluid in intracranial dissections, whereas it was more difficult to detect in extracranial dissections because of the intermediate-to-high signal of the normal perivascular structures and slow flow proximal and distal to the dissection. In two patients examined within 36 h of the onset, mural thickening was of intermediate signal intensity on T1-weighted images and high signal on spin-density and T2-weighted images. MRA showed abrupt stenosis in 2 patients and disappearance of flow signal at and distal to the dissection in 5. Follow-up arteriography, MRI or MRA showed findings consistent with occlusion of the dissected vessel in 6 of 8 patients.

Adult↗
PubMed1997

Case report. MRI and MR angiography of basilar artery dissection in a child.

MRI showed a pontine infarct and mural thickening of intermediate signal in T1-weighted images proximal to occlusion of the basilar artery in a 10-year-old boy. Two days later the mural thickening was of high signal, consistent with methaemoglobin formation and MR angiography (MRA) showed nonspecific lack of flow in the mid-segment of the basilar artery, which corresponded to a tapered occlusion at arteriography. MRI is more useful than MRA for noninvasive diagnosis of basilar artery dissection.

Aortic Dissection↗
PubMed1997

Ex-vivo MR imaging of liver intracellular contrast agents.

The objective is to evaluate whether an ex-vivo model can be used to test intracellular contrast agents for MR imaging of the liver. T1 weighted inversion recovery, proton density spin echo and T2* weighted gradient echo images of the liver were acquired at 0.5 T in 10 rats before and 30 min after intravenous injection of 0.075 mmol/kg Gadolinium benzyloxypropionictetraacetate (Gd-BOPTA, n = 5) or 0.015 mmol/kg dextran magnetite (DM, n = 5), Four additional animals served as controls. After exsanguination and perfusion with saline and formalin, specimens of the liver and brain were embedded in an agar gel and examined with MR imaging one to three weeks later using the same protocol. In-vivo, the mean liver signal enhancement caused by Gd-BOPTA in T1, proton density and T2* weighted images was +23%, +28% and -70%, respectively. The mean liver signal enhancement caused by DM was -71%, -76% and -94%. In-vitro, no signal change was seen in the brain of animals injected with Gd-BOPTA and DM as compared to controls. Liver signal was increased by Gd-BOPTA and decreased by DM. Mean liver enhancement rate induced by Gd-BOPTA was +22%, +5% and +27% for T1, proton density and T2* weighted images, respectively. Mean liver enhancement rate induced by DM was -27%, -19% and -31%. MR imaging signal changes induced by liver intracellular contrast agents are still appreciable in an ex-vivo model. The latter might be useful for for preliminary investigation of intracellular contrast agents for MR imaging of the liver.

Animals↗
PubMed1997

Reversal of syphilitic hydrocephalus with intravenous penicillin.

BACKGROUND: CSF shunting procedures are generally considered the fundamental therapy of syphilitic hydrocephalus. METHODS: We followed up with CSF analysis and MR imaging a patient with progressive mental and gait disturbances and tetraventricular hydrocephalus due to tertiary syphilis who was treated for 14 days with high dose intravenous penicillin alone. RESULTS: Clinical and CSF abnormalities resolved within a few months, whereas the hydrocephalus disappeared only 30 months after therapy. CONCLUSIONS: Before consideration of a CSF shunting procedure, a trial of high dose intravenous penicillin is warranted for patients with syphilitic hydrocephalus.

Adult↗
PubMed1997

Identification of the feeding arteries of spinal vascular lesions via phase-contrast MR angiography with three-dimensional acquisition and phase display.

PURPOSE: To determine whether identification of the feeding arteries of spinal vascular lesions with phase-contrast MR angiography benefits from the higher spatial resolution of three-dimensional (volume) acquisitions and flow-direction information provided by the phase reconstruction of two-dimensional acquisitions. METHODS: Fifteen patients with high- or low-flow spinal vascular lesions proved by spinal arteriography underwent MR angiography with phase-contrast techniques. Arteriographic and MR angiographic studies were reviewed to identify the arterial feeders of spinal vascular lesions. RESULTS: On modulus reconstructions of coronal 2-D or 3-D acquisitions, three of four arteries feeding high-flow lesions and three of 14 arteries feeding low-flow lesions were identified as hypertrophic vessels joining the parent intercostal or cervical arteries. Of 11 intradural veins draining dural arteriovenous fistulas, three were identified on coronal 2-D acquisitions and six on coronal 3-D acquisitions as vessels that coursed from a neural foramen to a midline tangle of vessels. Phase reconstruction showed ascending and descending flow patterns in two patients with intramedullary arteriovenous malformations, and diverging flow in perimedullary veins draining a hemangioblastoma. In nine patients with dural arteriovenous fistulas, phase reconstruction provided information as to the level of the arterial feeders. Phase reconstruction in coronal plane acquisitions also provided evidence of centripetal flow. CONCLUSION: Three-dimensional acquisitions and phase display of 2-D acquisitions improved the visibility of arterial pedicles of spinal vascular lesions at phase-contrast MR angiography.

Adult↗
PubMed1996

MRI of cerebellar white matter damage due to carbon monoxide poisoning: case report.

Extensive bilateral cerebellar white matter signal change, with sparing of the overlying cortex, consistent with demyelination was seen in a 12-year-old boy who had suffered carbon monoxide poisoning 6 years previously. His youth at the time of exposure and the long delay between exposure and examination might account for this unusual finding.

Carbon Monoxide Poisoning↗
PubMed1996

A preliminary open trial with nimodipine in patients with cognitive impairment and leukoaraiosis.

We treated, in a preliminary open trial, 31 patients presenting with cognitive impairment, progressive bilateral motor dysfunction, and leukoaraiosis on computed tomography (CT) with a 90-mg daily dose of nimodipine for a period as long as 1 year (minimum: 96 days, maximum: 424 days), to study the safety and possible effects on functional and cognitive conditions throughout this period. Of the 29 patients who had been followed for at least 9 months, most (82%) remained stable or improved as evaluated by the Global Deterioration Scale. A significant improvement was observed in the total Sandoz Clinical Assessment Geriatric scale score (44.66 +/- 7.17 at baseline vs. 36.86 +/- 9.34 at exit, analysis-of-variance time effect, p < 0.0001). These data indicate that nimodipine, chronically administered in patients presenting with cognitive impairment, progressive bilateral motor dysfunction, and leukoaraiosis on CT, is safe and might have beneficial effect, to be confirmed by a randomized trial.

Adult↗
PubMed1996

Usefulness of MR signal intensity in distinguishing benign from malignant pleural disease.

OBJECTIVE: The aim of this study was to analyze the potential usefulness of MR signal intensity in differentiating malignant from benign pleural disease. SUBJECTS AND METHODS: Forty-five patients with pleural lesions identified on CT scans were subsequently examined by MR imaging at 0.5 T. T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted spin-echo images were obtained. For 34 patients, a diagnosis of malignant (n = 18) or benign (n = 16) disease was established. The morphologic features of the pleural lesions and MR signal intensity on T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted images were evaluated, and the ratio of lesion to muscle signal intensity was computed. RESULTS: Assessment of morphologic features by MR imaging and CT was not significantly different. High signal intensity on proton density-weighted and T2-weighted images was observed in all malignant lesions and in two benign lesions (sensitivity, 100%; specificity, 87%; negative predictive value, 100%). The ratio of lesion to muscle signal intensity on T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted images discriminated between malignant and benign lesions (p < .0001). For the subgroup of lesions misinterpreted by CT (n = 6), the evaluation of MR signal intensity on long-TR images made it possible to differentiate malignant from benign conditions. CONCLUSION: MR signal intensity is a valuable additional feature for differentiating malignant from benign pleural disease. Signal hypointensity with long-TR sequences is a reliable predictive sign of benign pleural disease.

Adult↗
PubMed1995

The cardiovascular outcome of patients with motor impairment and extensive leukoaraiosis.

BACKGROUND AND METHODS: The long-term outcome of patients with motor impairment and extensive leukoaraiosis on computed tomographic scan is unknown. We studied the incidence of stroke, myocardial infarction, and death in 31 such patients (cases) and in 68 neurologic patients without leukoaraiosis (controls). The patients in both groups had a routine neurologic and cardiovascular assessment and were followed up for 51.9 +/- 20.1 (mean +/- SD) months (cases) and 49.5 +/- 18.6 months (controls). RESULTS: The 6-year risk of cumulative stroke, as determined by life table analysis, was 49% among cases and 16% among controls (hazard ratio, 3.0; 95% confidence interval, 1.2 to 7.5). The risk of stroke or myocardial infarction was 69% vs 36% (hazard ratio, 2.9; 95% confidence interval, 1.4 to 6.2). The stroke risk remained significantly increased among cases after adjustment for age, sex, and any conventional vascular risk factor, while it was reduced (hazard ratio, 2.5; 95% confidence interval, 0.8 to 7.4) after adjustment for history of lacunar stroke was corrected for and was almost halved (hazard ratio, 1.6; 95% confidence interval, 0.5 to 4.6) after adjustment for the presence of lacunar infarction images on computed tomographic scan. CONCLUSIONS: Patients with motor impairment and extensive leukoaraiosis have a very poor cardiovascular outcome. Lacunar infarction might be the major determinant of the outcome in these patients.

Brain Diseases↗
PubMed1995

MRI of spinal epidural lymphoma.

We reviewed the MRI features in eight patients with spinal epidural lymphoma (clinically primary in 4 patients); one patient had multiple lesions. The cervical spine was involved in one patient, the thoracolumbar spine in 5 and the sacrum in two. Mean longitudinal extension of the epidural lesion was 2.6 vertebral segments. The tumours were homogeneously isointense with the spinal cord on T1-weighted images and isointense or hyperintense on proton-density and T2-weighted images. The spinal cord was compressed in four patients but showed signal changes in only one. In five patients the lesions communicated through the intervertebral foramina with paravertebral soft tissue masses. In all but one of the patients diffuse signal changes in the vertebral body marrow consistent with osteolytic or osteoblastic changes were identified adjacent to or at distance from the epidural lesion. Vertebral collapse was observed in two patients.

Adult↗
PubMed1995

MRI of congenital Foix-Chavany-Marie syndrome.

MRI findings of bilateral central macrogyria allowed the diagnosis of a congenital variant of Foix-Chavany-Marie syndrome in four patients aged between 13 and 32 years, with facio-pharyngo-glosso-masticatory central diplegia, mental retardation and seizures.

Adolescent↗
PubMed1995

Corticospinal tract degeneration in motor neuron disease.

Long-repetition-time spin-echo MR images showed symmetric hyperintensity of the intracerebral corticospinal tracts in two patients with clinical and neurophysiologic diagnosis of primary lateral sclerosis and amyotrophic lateral sclerosis. In both, axial low-flip-angle gradient-echo images of the cervical spine showed hyperintensity of the lateral columns of the cord consistent with antegrade degeneration of the crossed corticospinal tracts.

Adult↗