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S Bastianello

Publications and source records attributed to S Bastianello.

At least 73 records · Page 4Linked to original sources
PubMed1997

Interscanner variation in brain MRI lesion load measurements in MS: implications for clinical trials.

We evaluated the effect of interscanner variation on brain MRI-measured lesion volumes and measurement reproducibility in MS. Twenty clinically definite MS patients were each scanned on two or three scanners (a total of 14 scanners were used). In addition, a formalin-fixed MS brain was studied on eight scanners from different manufacturers and with different field strengths. For the formalin-fixed MS brain, on each machine we obtained two scans with slice thicknesses of 5 and 3 mm. Only 5-mm-thick slices were obtained from patients. The lesion volume present on each scan was evaluated three times by a single observer in random order, using a local thresholding technique. In two groups of eight patients scanned on machines with different field strengths, the mean lesion volumes present on scans obtained at 1.5 T were significantly higher than those measured on scans obtained with machines operating at 0.5 and 1.0 T (p < 0.01). When a single observer repeatedly evaluated the same scan, a median introbserver agreement of 98.7% (95% CI, 97.9 to 99.1) was achieved. However, when the observer evaluated the scans from different MRI scanners, the agreement (an interscanner agreement) fell to 91.1% (CI, 90.2 to 94.1). When only scanners operating at 1.5 T were considered, the median interscanner agreement was 96.7% (CI, 95 to 97.5). Also, for the formalin-fixed MS brain, the intraobserver agreements obtained with both slice thicknesses were significantly higher than the corresponding interscanner agreements. The interscanner agreement, but not the intraobserver agreement, obtained with a slice thickness of 3 mm was higher than that obtained with a slice thickness of 5 mm. Our results indicate that lesion volume measurements in MS are influenced significantly by the use of different MR scanners and that a patient included in a serial study should be always scanned with the same MR machine using 3-mm thick slices.

Adult↗
PubMed1997

Fast spin-echo and fast fluid-attenuated inversion-recovery versus conventional spin-echo sequences for MR quantification of multiple sclerosis lesions.

PURPOSE: To compare fast spin-echo (FSE) and fast fluid-attenuated inversion recovery (FLAIR) sequences with conventional spin-echo (CSE) MR imaging in the quantification of the number and volume of multiple sclerosis lesions. METHODS: In 30 patients with relapsing-remitting multiple sclerosis, we calculated the total number and volume of lesions detected with each of the three sequences using a semiautomated program. RESULTS: On CSE sequences, we calculated a total of 2,583 lesions with a global volume of 836.3 cm3. With FSE sequences, we observed a 16% relative reduction in the number of lesions detected and a 25% relative reduction in global volume as compared with CSE. With fast FLAIR sequences, we detected a significantly lower number and volume of infratentorial lesions, whereas at the cortical/subcortical level the lesions were both more numerous and bulkier than on CSE sequences. Finally, we observed a higher lesion/white matter contrast, a significant reduction in time required for the quantification of lesion load, and a very low interobserver variability in favor of fast FLAIR sequences. CONCLUSION: Despite its limitations in the detection of infratentorial lesions, the fast FLAIR sequence in conjunction with a semiautomated quantification program provides a reliable means to evaluate the total lesion burden in patients with MS.

Adult↗
PubMed1997

[Fast spin echo and fast fluid attenuated inversion recovery sequences in multiple sclerosis].

Fast spin echo (FSE) and fast fluid attenuated inversion recovery (fast-FLAIR) MR sequences were compared with conventional spin echo (CSE) in quantitating multiple sclerosis (MS) lesion burden. For each sequence, the total number and volume of MS lesions were calculated in 38 remitting MS patients using a semiautomated lesion detection program. CSE, FSE and fast-FLAIR images were reported on randomly and at different times by two expert observers. Interobserver differences, the time needed to quantitate MS lesions and lesion signal intensity (contrast-to-noise ratio and overall contrast) were considered. The lesions were classified by site into infratentorial, white matter and cortical/subcortical. A total of 2970 lesions with a volume of 961.7 cm3 was calculated on CSE images. FSE images depicted fewer (16.6%; p < .005) and smaller (24.9%; p < .0001) lesions and the differences were statistically significant. Despite an overall nonsignificant reduction for fast-FLAIR images (.5% and 4.8% for lesion number and volume, respectively), significantly lower values (lesion number: p < .01; volume: p < .04) were observed for infratentorial lesions, while significantly higher values were seen for cortical/subcortical lesions (lesion number: p < .01; volume: p < .02). A higher lesion/white matter contrast (p < .002), a significant time saving for lesion burden quantitation (p < .05) and very low interobserver variability were found in favor of fast-FLAIR. Our data suggest that, despite the limitations regarding infratentorial lesions, fast-FLAIR sequences are indicated in MS studies because of their good identification of cortical/subcortical lesions, almost complete interobserver agreement, higher contrast-to-noise ratio and the limited time needed for semiautomated quantitation.

Adult↗
PubMed1996

Power spectrum analysis contribution to the detection of cardiovascular dysautonomia in multiple sclerosis.

In multiple sclerosis (MS) autonomic cardiovascular dysfunction is an uncommon, but potentially dangerous event, to which studies of spectral analysis of heart rate variability have not been applied, yet. MATERIAL AND METHODS--We studied 16 patients with definite MS (11 women and 5 men, mean age 30.3 +/- 7.4 yrs., mean EDSS 2.06 +/- 1.42) and 16 sex- and age-matched healthy controls. Besides cardiovascular reflex tests (valsalva manoeuvre, deep breathing, lying to standing, Blood Pressure response to standing and sustained handgrip), each underwent spectral analysis of the R-R interval short-term variability at rest and after tilting, to detect three components: very low frequency (VLF), low frequency (LF) and high frequency (HF). A recent brain MRI was obtained from patients, to compare plaque characteristics with spectral parameters. RESULTS--At cardiovascular reflexes, only four patients (25%) showed an impairment, mostly of a mild degree. VLF and LF at rest were lower in MS subjects than in controls (p < 0.01). No significant correlation was found between spectral parameters and lesion area or localization as detected on MRI. CONCLUSIONS--Spectral analysis could usefully flank reflex tests to detect autonomic subclinical cardiovascular abnormalities.

Adult↗
PubMed1996

Magnetic resonance imaging changes with recombinant human interferon-beta-1a: a short term study in relapsing-remitting multiple sclerosis.

OBJECTIVE: To evaluate whether recombinant human interferon-beta-1a significantly affects disease activity as measured by a reduction in the number and volume of Gd enhancing lesions on monthly MRI. The study also evaluated the effect on six-monthly T2 weighted abnormality and relapse frequency. METHODS: After a baseline scan and a six month pretreatment period, 68 patients were randomly assigned to receive either 3 MIU or 9 MIU of interferon-beta-1a by subcutaneous injection three times a week for six months. All patients were examined by Gd enhanced MRI every month in both pretreatment and treatment periods. The evaluation of Gd enhancing lesions was performed blind at the end of the study. RESULTS: The mean number of Gd enhancing lesions was higher during the pretreatment period than during treatment. This difference was statistically significant for the two different dose subgroups (3.5 v 1.8, P < 0.001 for the 3 MIU group and 2.4 v 0.9, P < 0.001 for the 9 MIU group, corresponding to a reduction of 49% and 64% respectively). The mean volume of Gd enhancing lesions also significantly decreased by 61% (3 MIU group) and 73% (9 MIU group). These reductions were evident only after the first month of treatment. The six-monthly rate of new lesions as seen in T2 weighted images showed a similar trend of reduction with treatment (65% and 70% respectively). Lesion volume on T2 scans significantly increased during the pretreatment period whereas it remained almost stable during the treatment period in both groups. Clinical relapse rate was significantly reduced by treatment (53% for the 3 MIU group, P < 0.001; 69% for the 9 MIU group, P < 0.001). CONCLUSION: Interferon-beta-1a seemed effective in reducing disease activity in relapsing-remitting multiple sclerosis at both the doses used.

Adolescent↗
PubMed1996

Posterior circulation infarcts simulating anterior circulation stroke. Perspective of the acute phase.

BACKGROUND AND PURPOSE: Ischemic stroke patients whose initial clinical presentation suggests an involvement of the anterior circulation (AC) are sometimes found to have a posterior circulation (PC) infarct, a fact that may generate erroneous decisions in clinical management. We investigated the prevalence of this misdiagnosis in the first few hours after stroke onset. METHODS: We performed a cohort study of 158 patients hospitalized within 5 hours of onset of a presumed AC ischemic stroke, as diagnosed on clinical grounds. RESULTS: Final CT or pathology diagnosis was AC infarct in 128 patients (81%), a repeatedly negative CT in 14 (9%), PC infarct (5 pons, 1 midbrain and cerebellum, 6 supratentorial territory of the posterior cerebral artery) in 12 (8%), and other or undiagnosed lesions in 4 (3%). AC and PC stroke patients did not differ in terms of age, vascular risk factors, and initial severity, but the latter were more frequently men (83% versus 53%; P = .04), were hospitalized later (mean +/- SD, 168 +/- 86 versus 109 +/- 55 minutes; P = .001), and presented a pure motor hemiparesis or a sensorimotor stroke (50% versus 33%) more often than their counterparts. At baseline CT, PC stroke patients never exhibited an early parenchymal hypodensity in the carotid territory or a hyperdense middle cerebral artery, which were instead found in 59% (P = .0003) and 31% (P = .02) of AC stroke patients, respectively. Early neurological deterioration, 1 month case-fatality rate, and disablement in survivors were comparable in the two groups. CONCLUSIONS: Shortly after onset the clinical discrimination between AC and nontypical PC infarcts is not reliable, which explains the frequent occurrence of this misdiagnosis. Emergency CT scan helps in the differential diagnosis only when it demonstrates an early focal hypodensity within the carotid territory.

Acute Disease↗
PubMed1996

Hemorrhagic transformation of brain infarct: predictability in the first 5 hours from stroke onset and influence on clinical outcome.

OBJECTIVE: To identify, in the first 5 hours of acute brain infarct, clinical and radiologic predictors of subsequent hemorrhagic transformation (HT), and to evaluate its influence on the clinical course. BACKGROUND: The identification of early predictors of HT might be important to plan antithrombotic or thrombolytic treatments. PATIENTS: One hundred fifty consecutive patients with cerebral anterior circulation infarct systematically underwent a first CT within 5 hours of onset. During the first week after stroke, we performed a repeat CT or autopsy to look for HT. Outcome measures were early neurologic deterioration within the first week of onset and 30-day case fatality rate and disability. RESULTS: HT was observed in 65 patients (43%): 58 (89%) had a petechial HT and seven (11%) a hematoma. Among initial clinical an CT findings, the only independent predictor of HT was early focal hypodensity. Its presence was associated with subsequent HT in 77% of cases (95% CI, 68 to 86%), whereas its absence predicted the absence of subsequent HT in 94% of cases (95% CI, 89 to 99%). No baseline clinical or CT characteristic differentiated patients with petechial HT from those with hematoma. Antithrombotic and antiplatelet agents did not influence the occurrence of either type of HT. The frequency of early neurologic deterioration and of 30-day death or disability in HT patients was twice as high as in those without HT. However, a large-sized infarct and the presence of mass effect at the repeat CT or autopsy were the only factors independently linked to both the outcome events, irrespective of the development of HT. Clinical evolution of HT patients given antithrombotics was comparable with that of HT patients not receiving these drugs. CONCLUSIONS: HT of a brain infarct is a common event that occurs independently of anticoagulation and can be reliably predicted as early as 5 hours from stroke onset by the presence of focal hypodensity at CT. Apart from the infrequent cases of massive hematoma, HT does not influence prognosis, whereas a poor outcome in HT patients is correlated with a higher frequency of large edematous infarcts in this subgroup. The clinical course and final outcome of HT in anticoagulated patients does not differ from that of non-anticoagulated HT patients.

Aged↗
PubMed1995

Progressing neurological deficit secondary to acute ischemic stroke. A study on predictability, pathogenesis, and prognosis.

OBJECTIVES: To identify predictors and possible pathogenetic mechanisms of early neurological deterioration in patients with acute ischemic strokes and to evaluate their impact on clinical outcome. DESIGN: Case series. SETTING: University hospital's stroke unit. PATIENTS: A continuous series of 152 patients with first-ever ischemic hemispheric strokes were hospitalized within 5 hours of onset, evaluated with the Canadian Neurological Scale, and underwent a computed tomographic (CT) scan. The initial subset of 80 patients also underwent angiography. A repeated CT scan or autopsy was performed within 5 to 9 days of a patient's stroke. Progressing neurological deficit was defined as a decrease of one point or more in the global neurological scale score during hospitalization, when compared with that at entry. RESULTS: The conditions of 39 patients (26%) deteriorated during the initial 4 days; 20 patients (51%) had an impaired level of consciousness, and 19 patients (49%) had impaired limb strength and/or speech. They had been hospitalized earlier and had higher serum glucose levels at admission; the baseline CT scans of these patients showed an early focal hypodensity and initial mass effect more frequently. On the repeated CT scan (144 patients) or at autopsy (eight patients), patients with a progressing course more frequently had large infarcts, severe mass effect, and hemorrhagic infarction. We found no differences with regard to demographic data, medical history, and treatments that were given; only subcutaneous heparin calcium was more frequently administered to patients with a progressing course. Twenty-two (27%) of the 80 patients who underwent angiography had a progressing course, of whom 20 (91%) had an intracranial and/or extracranial arterial occlusion, with collateral blood supply in seven patients (35%). Logistic regression analysis showed that the independent predictors of progression were the serum glucose levels at admission and the early focal hypodensity with cortical and corticosubcortical locations, with the positive predictive values of the latter being 34% (95% confidence interval [CI], 26% to 42%) and 57% (95% CI, 47% to 67%), respectively. Among patients who underwent angiography, logistic regression analysis showed a significant correlation between carotid siphon occlusion and a progressing course. The 30-day case-fatality ratio and disability (Barthel index, < 60) were higher in patients with a progressing course (36% and 54% vs 12% and 35%, respectively). CONCLUSIONS: Early stroke deterioration is still an event that is difficult to predict; it is largely determined by cerebral edema following an arterial occlusion, as indicated by an early focal hypodensity and initial mass effect on the baseline CT scan. Since early deterioration anticipates a bad outcome in 90% of patients, it might be used as an early surrogate end point in therapeutic trials.

Acute Disease↗
PubMed1995

Clinical and MRI assessment of disease activity in patients with multiple sclerosis after influenza vaccination.

We investigated the possible effects of influenza vaccination on disease activity in multiple sclerosis (MS). Six patients were evaluated clinically during the year preceding and the year following influenza vaccination. Gadolinium-enhanced magnetic resonance imaging (Gd-MRI) was performed one day before and at days 15 and 45 after vaccination. Cumulatively, we did not observe increases in clinical or MRI disease activity following vaccination, with the exception of one case. This was the patient with the highest clinical disease activity during the year preceding vaccination. These results support and supplement previous observations, indicating that influenza vaccination is a safe procedure in multiple sclerosis. Nevertheless, it should be used with caution in patients with active/progressing disease.

Adult↗
PubMed1995

Clinical and prognostic correlates of stroke subtype misdiagnosis within 12 hours from onset.

BACKGROUND AND PURPOSE: Pure motor hemiparesis and sensorimotor stroke syndromes are not accurate predictors of lacunar infarct when described in the first 12 hours of stroke onset. We evaluate here whether this inaccuracy of clinical diagnosis might have influenced the planning of patient management either in routine practice or in therapeutic trials. METHODS: A consecutive hospital series of 517 first-ever ischemic hemispheric stroke patients presented lacunar or nonlacunar syndromes at the first examination within 12 hours of the event. A distinction was subsequently made, by means of a CT scan or autopsy performed within 15 +/- 2 days of stroke, between patients affected by lacunar or nonlacunar infarcts. We compared stroke risk factors, considered to be indicative of potential pathogenetic mechanisms, and the clinical outcome of lacunar infarct versus nonlacunar infarct patients and those of lacunar syndrome versus nonlacunar syndrome patients. RESULTS: Two hundred nineteen patients (42%) presented a lacunar syndrome and 298 (58%) a nonlacunar syndrome, while 170 (33%) had lacunar infarcts and 347 (67%) nonlacunar infarcts. Lacunar infarct patients were more frequently associated with hypertension and a previous transient ischemic attack and less frequently with atrial fibrillation when compared with their nonlacunar infarct counterparts, whereas no differences were apparent between lacunar syndrome and nonlacunar syndrome patients. Logistic regression analysis showed that hypertension and a previous transient ischemic attack on the one hand and atrial fibrillation on the other were strongly correlated with the diagnosis of lacunar infarct and nonlacunar infarct, respectively, while no risk factor was correlated with the diagnosis of lacunar syndrome. Twenty-two percent of lacunar infarct patients and 68% of nonlacunar infarct subjects had a poor outcome (death plus disability of survivors) as opposed to 40% of lacunar syndrome and 63% of nonlacunar syndrome patients. Logistic regression selected age, severity of neurological deficit at entry, cardiopathies, diabetes, and lacunar infarct, but not lacunar syndrome, as predictors of outcome. CONCLUSIONS: The inaccurate clinical diagnosis of lacunar infarct made in the first 12 hours of stroke might lead to no distinction being made between stroke subgroups with potentially different pathogenetic mechanisms and prognostic estimates, thus negatively influencing the planning of patient management.

Age Factors↗
PubMed1995

Human recombinant interferon beta in the treatment of relapsing-remitting multiple sclerosis: preliminary observations.

An open comparative, randomized trial with recombinant human interferon beta (r-hIFN-beta) involving 72 patients with clinically definite and/or laboratory-supported relapsing-remitting MS is in progress at the University 'La Sapienza' and at the S. Camillo Hospital of Rome. After a 6 month period of clinical and magnetic resonance imaging (MRI) observation (baseline findings), patients are randomly assigned to one of two treatment groups receiving 3 or 9 MIU of recombinant human IFN-beta (r-hIFN-beta) self-administered by subcutaneous injection three times a week for 6 months. All patients are examined by MRI with and without gadolinium (Gd-DTPA) every 4 weeks for the entire duration of the study (12 months). The main aim of the study is to test the hypothesis that r-hIFN-beta may halt or slow the progression of the disease by showing a significant reduction in MRI activity. This will be achieved by comparing pre and post-treatment periods. As an additional clinical end point, the exacerbation rate during these two periods will be compared. This study began in June 1993 and the final analysis of MRI data is planned for the spring of 1995.

Adjuvants, Immunologic↗
PubMed1994

Influence of hyperglycaemia on infarct size and clinical outcome of acute ischemic stroke patients with intracranial arterial occlusion.

We investigated the effects of hyperglycaemia on infarct size of 82 acute ischaemic stroke patients with angiographically diagnosed intracranial occlusion in middle cerebral artery territory. There were 9 diabetics, 40 non-diabetic hyperglycaemics and 33 non-diabetic normoglycaemics (mean age 67 +/- 8 SD years, male/female ratio 1:1). For each patient the infarct at CT was compared to that predicted from the location of the arterial occlusion. The extent of the infarct was then classified as equal to, smaller than and larger than estimated, taking a standard anatomical template of arterial territories as reference. The results were analysed separately according to the presence or absence of a collateral blood supply (CBS) at angiography. The clinical outcome at 30 days was also evaluated. The 35 patients lacking CBS had a high frequency of equal to estimated lesions (75%), without substantial differences among the three subgroups (72% of hyperglycaemics, 82% of normoglycaemics and 67% of diabetics; Fisher's exact test not significant for any of the pairwise comparisons). On the contrary, the 47 patients with CBS exhibited an overall predominance of smaller than estimated lesions (66%) but with a very uneven distribution among hyperglycaemics, normoglycaemics and diabetics (82%, 64% and 0%, respectively; p < 0.05 at Fisher's exact test for diabetics vs hyperglycaemics). Finally, the clinical outcome was bad (death and neurological impairment) in 89% of diabetics, 72% of hyperglycaemics and 54% of normoglycaemics (p < 0.05). These results suggest that in patients with intracranial arterial occlusion associated with CBS the effects of hyperglycaemia might be beneficial in non-diabetics and harmful in diabetics.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

A controlled trial of mitoxantrone in multiple sclerosis: serial MRI evaluation at one year.

We present the results of a randomized double-blinded placebo controlled, multicenter trial, of low-dose mitoxantrone (MX), after one year, in 25 patients with relapsing-remitting multiple sclerosis, who had serial enhanced magnetic resonance imaging (MRI). Treatment groups were balanced for age, gender, duration of illness and neurological disability. Five of the 13 MX patients and 10 of the 12 placebo patients had exacerbations during treatment (p < 0.02). The mean change in the extended disability status scale was not significantly different between the MX and placebo treatment groups. Serial Gadolinium-DTPA enhanced MRI detected no significant difference between the MX treated and placebo groups in the mean total number of new, enlarging, or Gadolinium-DTPA enhancing lesions; there was a trend toward a reduction of new, enlarging and Gadolinium-DTPA enhancing lesions in MX patients. Despite this ameliorating effect, the results indicate that serial Gadolinium-DTPA enhanced MRI, performed over one year in a limited number of patients, could not provide conclusive evidence for a role of MX therapy in relapsing-remitting multiple sclerosis.

Adolescent↗
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↗
PubMed1994

Pure motor hemiparesis and sensorimotor stroke. Accuracy of very early clinical diagnosis of lacunar strokes.

BACKGROUND AND PURPOSE: Clinical differentiation of lacunar from nonlacunar strokes in the very early phase could help to exclude patients with lacunar stroke from pharmacologic trials designed for nonlacunar strokes, namely, those with thrombolytic agents. In a continuous series of acute ischemic stroke patients, we evaluated how accurately a clinical diagnosis of pure motor hemiparesis or sensorimotor stroke formulated in the first hours from onset predicts a lacunar stroke documented by cerebral computed tomography or by autopsy. METHODS: We examined 517 patients (299 men, 218 women; mean +/- SD age, 67 +/- 10 years) within 12 hours (mean +/- SD, 6.1 +/- 3.2 hours) of the event. At hospital admission, we observed 151 (29%) patients with pure motor hemiparesis and 68 (13%) patients with sensorimotor stroke. RESULTS: Computed tomography or autopsy was compatible with a lacunar stroke (ie, detection of a lacune or permanently negative computed tomography) in 170 (33%) patients, of whom 123 (72%) had pure motor hemiparesis and 47 (28%) had sensorimotor stroke. This led to a sensitivity of 72%, a specificity of 72%, a positive predictive value of 56%, and a negative predictive value of 84%. Overall positive predictive value of pure motor hemiparesis was 58% (60% for two areas and 58% for three areas involved), and that of sensorimotor stroke was 51% (87% for two areas and 40% for three areas involved). By separately evaluating the sides of lesions, we found a positive predictive value of 46% for right-side infarcts and of 72% for left-side infarcts. Right-side lesions constituted 51% of lesions in lacunar syndrome patients with lacunar stroke, 76% in those with nonlacunar stroke, 19% in nonlacunar syndrome patients with lacunar stroke, and 31% in those with nonlacunar stroke (P < .0001). During the first days of hospital stay we observed a deterioration of 21% of lacunar syndrome patients with nonlacunar stroke and an improvement of 49% of nonlacunar syndrome patients with lacunar stroke, with appearance and disappearance of symptoms of cortical involvement, respectively. The examination of these patients after the occurrence of these clinical changes would have led to a daily increase of the positive predictive value up to a maximum of 66% at day 7. CONCLUSIONS: Pure motor hemiparesis and sensorimotor stroke diagnosed within 12 hours of the event are poorly predictive of lacunar strokes. Hence, the very early identification of these syndromes cannot be used for patient selection in therapeutic trials.

Aged↗