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A Pierallini

Publications and source records attributed to A Pierallini.

33 records · Page 2Linked to original sources
PubMed1997

Supratentorial diffuse astrocytic tumours: proposal of an MRI classification.

The aim of this study was to obtain an MRI severity-related classification of diffuse astrocytic tumours able to integrate the histological data in the grading of such tumours. We studied presurgical MR images of 91 patients with a histological diagnosis of astrocytoma, anaplastic astrocytoma and glioblastoma. A score ranging from 1 to 3 was assigned by two independent readers to each of the following MR features: oedema, mass effect, contrast enhancement, borders, signal homogeneity, necrosis, haemorrhage and flow void. Statistical analysis showed significant differences in the mean MRI scores between the three histological grades. Contrast enhancement was found to be the best predictor of the histological grade followed by necrosis, signal homogeneity and border scores. This classification represents a simple and reproducible means of carefully evaluating some macroscopic characteristics of these tumours. It could be used to integrate histological data especially in cases in which tissue sampling defects may affect the validity of this examination.

Adult↗
PubMed1996

Relationship between thallium-201 uptake by supratentorial glioblastomas and their morphological characteristics on magnetic resonance imaging.

Single-photon emission tomography (SPET) with thallium-201 is used in the assessment of patients with gliomas because the amount of 201Tl accumulated by the tumoral cells increases in proportion to the degree of tumour malignancy, thus making it possible to differentiate high-grade from low-grade gliomas or recurrences from radiation necrosis. However, in large areas of tissue such as those examined in 201Tl SPET studies, the uptake of 201Tl may vary considerably even in tumours with the same histological diagnosis, as occurs in glioblastomas (GBMs). In order to evaluate the possible influence of the macroscopic characteristics of tumours on 201Tl uptake, we studied a series of 13 patients with histologically proven GBMs, comparing magnetic resonance imaging (MRI) parameters such as tumour dimensions, perilesional oedema, intratumoral necrosis and contrast enhancement with the degree of 201Tl uptake. The patients underwent both 201Tl SPET and MRI before surgery. The 201Tl index (tumour/contralateral unaffected brain) was calculated using two different region of interest (ROI) methods: the first employed irregular large ROIs (3.2+/-13.9 cm2) including pixels with more than 50% maximum activity; the second employed regular square small ROIs (2.7 cm2) centered on the maximum activity of the lesion. Of the MRI morphological parameters studied, only necrosis significantly reduced the degree of 201Tl uptake in GBMs when larger ROIs were used. However, by using small regular ROIs the influence of necrosis on 201Tl uptake was found to be less relevant. Since necrosis is related to tumour proliferative activity and represents a negative prognostic factor in astrocytoma, a possible underestimation of 201Tl uptake due to intratumoral necrosis must be carefully evaluated.

Brain↗
PubMed1996

Supratentorial glioblastoma: neuroradiological findings and survival after surgery and radiotherapy.

Few studies have attempted to correlate neuroimaging with outcome in patients with glioblastoma. Our aim was to evaluate the relationship between neuroradiological findings and survival in these patients. We studied 18 consecutive patients with glioblastoma who had undergone surgery and radiotherapy. We assessed the following features, using preoperative CT and/or MRI: tumour size, extent of necrotic area within the mass, extent of perifocal oedema and contrast enhancement. The mean survival was 14.2 +/- 5 months (range 6-22). The extent of radiological evidence of necrosis within the mass correlated significantly with survival time, whereas tumour size, perifocal oedema and contrast enhancement did not.

Aged↗
PubMed1994

No differences in corpus callosum size by sex and aging. A quantitative study using magnetic resonance imaging.

To identify normal variations in the magnetic resonance imaging appearances of the corpus callosum with regard to sex and age, a prospective study was performed in 130 normal subjects. Callosal measurements were calculated by morphometric analysis. There were no significant sex differences in corpus callosum area or the callosal subregions. The absolute area did not decrease significantly with aging in normal males or females. However, age-related changes of callosal configuration were shown by a decrease in the ratio of the rostrum and genu to the splenium.

Adolescent↗
PubMed1993

CT findings in peripheral mononeuropathies.

Thirty-six patients with a peripheral localized nerve lesion (18 of median nerve, 7 of ulnar nerve, 2 of radial nerve, 1 of lateral cutaneous brachii nerve, 1 of sciatic nerve, 5 of peroneal nerve and 2 of tibial nerve), were evaluated by Computed Tomography (CT). We used a high resolution scanner (Siemens Somatom CR) and we performed 2mm thickness slices. Sagittal and coronal reconstructed images were obtained too. Thirty-two out of 36 patients underwent surgery. CT scan was useful in all cases in defining the relationship between nerve lesions and surrounding tissues and in planning surgical procedures. The CT evaluation of tissues densities and characteristics allowed us to define the pathologic nature of the lesions in 10 cases.

Adult↗
PubMed1992

Sleep patterns in acute ischemic stroke.

We studied polysomnographic recordings using an Oxford Medilog 9000 System in 18 patients with ischemic stroke in the middle cerebral artery territory. All patients underwent neurologic examination and brain CT scan within 5 h after the onset of symptoms. Polysomnographic recordings were started immediately thereafter and went on for three nights. Clinical and polysomnographic follow-up were performed 3 weeks after admission. The number and duration of REM phases were significantly reduced in the acute phase. This reduction correlated with the severity of neurological deficit at outcome and with the anatomical site of the lesion on CT scan. Our data provide evidence that polysomnographic recording is useful to detect symptoms of patients with different clinical outcomes during the acute phase of ischemic stroke.

Aged↗
PubMed1991

Hyperdense middle cerebral artery CT sign. Comparison with angiography in the acute phase of ischemic supratentorial infarction.

The early CT finding of an hyperdensity of a portion of the middle cerebral artery Hyperdense Middle Cerebral Artery Sign (HMCAS), in patients with supratentorial stroke, is often indicative of an embolic occlusion. Aim of this study was to verify the incidence and reliability of the HMCAS and its possible correlation with early CT findings and with the extent of late brain damage. We studied 36 patients presenting with symptoms of stroke in the MCA territory, by means of CT and angiography performed respectively within 4 and 6 hours. Follow-up CT scans were then obtained after one week and three months from the ischemic event. The HMCAS was present in 50% of our patients and in this group it always correlated positively with the angiographic finding of occlusion. The same group presented a high incidence of early CT hypodensity (88%). Finally the presence of HMCAS might be considered a negative prognostic sign for the development of extensive brain damage.

Brain↗
PubMed1983

Successful repair of delayed rupture of the left ventricular wall after mitral valve replacement. Report of two cases.

Rupture of left ventricular wall (LVWR) following mitral replacement (MVR) is rare (0.5 to 7.3% of all MVR). Two "types" of LVWR have been recognized and attributed to technical errors during MVR and/or to co-existing unfavourable conditions. The two types are precisely located, and appear "early" during operation, at discontinuation of cardiopulmonary bypass (CPB). Miller et al. have described a "third type" LVWR which depends primarily on local conditions, is located between the other two and occurs "late". Successful repair is rare. The outcome is favourably influenced by intraoperative recognition. This paper reports two LVWRs "type III" which occurred among 282 MVR (0.7%) done in our Department since 1977. Both were successfully repaired respectively 12 (and again 48) and 15 hours after MVRs. To the best of our knowledge these are the only cases of successful repair of a "type III" LVWR reported in the literature. On the basis of this experience some considerations are presented.

Aged↗
PubMedDate not supplied

Early angiographic and CT findings in patients with hemorrhagic infarction in the distribution of the middle cerebral artery.

Hemorrhagic infarction subsequent to ischemic brain damage, even if small, slight, or marbled, can be detected by CT. The mechanisms that give rise to this transformation in humans are not well elucidated. Previous reports indicate that hemorrhagic infarction is most common in embolic stroke and large infarcts, and can worsen the clinical state of ischemic patients. We examined 36 patients with supratentorial ischemic signs and symptoms within the first hours after onset. CT was used to judge if hypodensity on early CT studies might predict the development of hemorrhagic infarction. Angiography was used to observe the site of arterial occlusion, the state of collateral circulation, and the mechanisms of late reperfusion. Hemorrhagic infarction was present in 18 of our 36 patients. Angiography revealed occlusion of the middle cerebral artery or internal carotid artery (three cases) in all patients. Hypodensity was present on early CT studies in all of the 18 patients who developed hemorrhagic infarction. The finding of hypodensity on CT studies performed soon after embolic ischemic stroke is strongly predictive of hemorrhagic transformation.

Brain Ischemia↗
PubMedDate not supplied

The usefulness of dynamic CT in patients with aneurysm of Willis circle. Comparative study with the angiography.

The diagnosis of cerebral aneurysm is currently based on the angiographic data. We have tried to evaluate the usefulness of a less-invasive examination, such as the dynamic-CT, in the diagnosis of intracranial aneurysm and of the possible and concomitant subaracnoid haemorrhage. The CT examination is useful in the diagnosis of both subarachnoid haemorrhage and giant trombosed aneurysm. It is less reliable than the angiography as regard to aneurysm of small dimension.

Adult↗