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Biomedical subjects

G Scotti

Publications and source records attributed to G Scotti.

At least 55 records · Page 3Linked to original sources
PubMed1996

Endovascular treatment of bacterial intracranial aneurysms.

We report three patients with bacterial intracranial aneurysms treated by the endovascular approach: two presented with sudden severe neurological deficits after a diagnosis of endocarditis; the other had suspected vasculitis. CT showed an intracerebral haematoma in all cases; angiography revealed bacterial aneurysms of distal branches of the middle cerebral artery in one. Because of the patients' condition and the location of the aneurysms, endovascular treatment was considered the fastest and safest treatment. Hyperselective catheterisation of the parent branch, close to the aneurysm, was performed with a microcatheter. A small amount of glue was injected to occlude both the aneurysm and a short segment of the diseased vessel. Follow-up angiography revealed occlusion of the aneurysm in all cases. One patient recovered completely; one recovered over some months, with neurological deficit due to the haematoma. The third patient suddenly worsened and died 9 days after treatment for a contralateral haematoma, due to rupture of a new bacterial aneurysm of the middle cerebral artery. Endovascular occlusion of the aneurysm and parent vessel may be an alternative to surgery in selected, severe cases of deep or distal bacterial intracranial aneurysms.

Adult↗
PubMed1996

Proton magnetic resonance spectroscopy and intracranial tumours: clinical perspectives.

Proton magnetic resonance spectroscopy (1H-MRS) was applied to characterize intracranial tumours of different hystological types. Seventy patients with intracranial neoplasms were studied before receiving surgery, radiotherapy or chemotherapy. All tumours were characterized by reduced or absent N-acetylasparate and increased signal from choline-containing compounds. Distinctive patterns were observed only for primitive brain neoplasms; high-grade gliomas were differentiated from low-grade ones by higher levels of choline-containing compounds. The metabolic aspects of metastatic lesions were similar to high-grade gliomas. These results, together with the limitations of 1H-MRS and future applications are reviewed.

Adenoma↗
PubMed1996

Brain and spinal cord MR in benign multiple sclerosis: a follow-up study.

We performed a clinical and magnetic resonance (MR) longitudinal study in 19 patients with benign multiple sclerosis (MS) to achieve a better definition of the nature of disability in MS. Patients with higher lesion volumes on conventional T2-weighted images at entry were those with more frequent relapses (p = 0.0004) and more new MR lesions (p = 0.003) during the follow up. However, 1/3 of these new lesions were located periventricularly and about 2/3 were small or intermediate in size. Two of the 11 patients (18%) with higher lesion volumes at entry developed progressive neurological deficits: in these two patients the new lesions seen on conventional T2 images had lower magnetization transfer ratios (p = 0.005) than those present in patients who remained clinically stable and a marked increase in hypointense lesion volumes on T1-weighted images was also found. Spinal cord cross-sectional area at C5 and MTR values for the seemingly normal white matter were similar to those found in normal controls. This study suggests that patients with benign MS have two different patterns of disease evolution, one characterized by very low clinical and MR activities, the other in which the lack of disabling symptomatology might be related to factors like site, size and nature of lesions. It also indicates that in patients with benign MS and high MR lesion loads the risk of developing a secondary progressive form of the disease is still present even after many years after onset.

Adult↗
PubMed1996

Correlation between brain MRI lesion volume and disability in patients with multiple sclerosis.

In this study we evaluated the relationships between clinical variables and lesion volumes measured from magnetic resonance imaging (MRI) scans in a large cohort of multiple sclerosis (MS) patients. One hundred and thirty patients with MS entered the study: 36 patients had relapsing-remitting (RR), 39 benign (B), 42 secondary progressive (SP) and 13 primary progressive (PP) courses. There was a significant correlation (r = 0.3; p = 0.0006) between the total lesion load and the EDSS score when the whole cohort of patients was considered. This correlation increased (r = 0.5) when only patients with RRMS and SPMS were considered. Our data indicate that a correlation between disability and MRI lesion volume in MS exists, but its strength is moderate.

Adult↗
PubMed1996

Comparison of triple dose versus standard dose gadolinium-DTPA for detection of MRI enhancing lesions in patients with MS.

We studied whether a triple dose of gadolinium-DTPA alone or in combination with delayed scanning increases the sensitivity of brain MRI for detecting enhancing lesions in patients with MS. We obtained T1-weighted brain MRI scans in two sessions for 22 patients with clinically definite MS. In the first session, we obtained one scan 5 to 7 minutes after the injection of 0.1 mmol/kg gadolinium-DTPA (standard dose). In the second session, 6 to 24 hours later, we obtained one scan before the two scans 5 to 7 minutes (for all patients) and one hour (for 11 patients) after the injection of 0.3 mmol/kg gadolinium-DTPA (triple dose). We detected 83 enhancing lesions in 14 patients when the standard dose of gadolinium-DTPA was used. The numbers of enhancing lesions increased to 138 (average increase 66%; p = 0.001) and the numbers of patients with such lesions to 18 (increase 28%) when we used the triple dose of gadolinium-DTPA. In addition, the total area per patient occupied by such lesions was greater (p < 0.0001) and lesion signal intensity higher (p = 0.0001) on the triple-dose scans than the standard-dose scans. There was an increase in the number of large enhancing lesions (p = 0.03) in the scans obtained 1 hour after the injection of the triple dose of gadolinium-DTPA. These data indicate that in patients with MS, a triple dose of gadolinium-DTPA can reveal many more enhancing lesions, which also appear larger. This suggests that the pathologic nature of "active" lesions in MS is heterogeneous, which might have impact on planning clinical trials.

Contrast Media↗
PubMed1995

Acute subarachnoid haemorrhage: 3D time-of-flight MR angiography versus intra-arterial digital angiography.

To evaluate the efficacy and reliability of 3D time-of-flight MR angiography (TOF MRA) as a noninvasive procedure, 27 patients with acute subarachnoid haemorrhage (SAH) were studied with MRA immediately before or after intra-arterial digital subtraction angiography (DSA).3DTOF MRA was performed with an axial slab of 60 mm centered on the circle of Willis and isotropic voxels. DSA showed 22 aneurysms and 1 dural arteriovenous fistula in 21 patients; the aneurysms ranged in size from 2 to 8mm. MRA failed to show 2 small aneurysms, at the origin of the posterior and anterior communicating arteries. The 3D display of the intracranial vessels obtained with maximum intensity projection (MIP) or targetted MIP sometimes rendered the aneurysms better than DSA. However, due to its high spatial resolution, DSA more clearly defined the overall anatomy of the walls of the normal and abnormal vessels.

Acute Disease↗
PubMed1995

An elastic computerized brain atlas for the analysis of clinical PET/SPET data.

An elastic computerized brain atlas was developed for the analysis of positron emission tomography/single-photon emission tomography (PET/SPET) data. It consists of a set of digital anatomical contours and a template of regions of interest, schematically describing the brain, derived from a currently used anatomical/functional brain atlas. A warping algorithm, matching equivalent contours, was implemented to elastically fit the atlas to individual brain images. The elastic computerized brain atlas was applied to representative magnetic resonance imaging (MRI)-PET/SPET studies, MRI providing the anatomical information used by the matching procedure. The atlas is suited for clinical use in a nuclear medicine environment.

Brain↗
PubMed1995

Transitional progressive multiple sclerosis: MRI and MTI findings.

Transitional progressive multiple sclerosis (MS) is quite an unusual form of presentation and course of the disease. A case with this progressive form is presented and brain MRI and MTI findings are discussed in relation to the possible insight they may provide for understanding the mechanisms that determine progressive disability in MS.

Adult↗
PubMed1995

A brain MRI study of different types of chronic-progressive multiple sclerosis.

INTRODUCTION: This study was performed to define the pattern of brain magnetic resonance imaging (MRI) abnormalities in chronic-progressive MS (MS). MATERIAL AND METHODS: Brain MRIs were obtained for 17 patients with secondary progressive MS (SPMS), 14 with primary progressive MS (PPMS) and 5 with "transitional" progressive MS (TPMS). RESULTS: Total lesion loads were different for the three groups of patients (p < 0.01). At post-hoc analysis, there was no difference between patients with TPMS and those with PPMS, while both these groups had lesion loads lower than those of patients with SPMS. Patients with PPMS with clinical signs indicating involvement of both brain and spinal cord had greater total lesion loads than those with clinical isolated spinal cord involvement (p < 0.05). CONCLUSION: These data indicate that brain MRI patterns of abnormalities are related to the clinical manifestations in patients with chronic-progressive MS.

Adult↗
PubMed1995

Brain magnetic resonance imaging and multimodal evoked potentials in benign and secondary progressive multiple sclerosis.

Brain MRI and multimodal evoked potentials (EPs) were obtained for 13 patients with benign multiple sclerosis and 13 patients with secondary progressive multiple sclerosis, matched for age and duration of the disease, to investigate the nature of the disability in multiple sclerosis. Patients with secondary progressive multiple sclerosis had significantly greater lesion loads for five of seven periventricular regions and for three of nine regions separate from the ventricles. Patients with secondary progressive multiple sclerosis also had more severe infratentorial atrophy scores (p = 0.04), whereas there were no differences between the two groups in number and extent of enhancing lesions. The frequencies were significantly higher and severities greater for multimodal EP abnormalities of all the modalities in patients with secondary progressive multiple sclerosis. At least one EP component was absent in 12 (92%) patients with secondary progressive multiple sclerosis but in only one patient (8%) with benign multiple sclerosis (p < 0.001). There was neurophysiological evidence for cervical cord involvement in eight (61%) patients with secondary progressive multiple sclerosis and in one with benign multiple sclerosis (p < 0.01). These data indicate that the total amount of lesions, the distribution, and the nature of the pathological process might all account for the development of disability in multiple sclerosis.

Age of Onset↗
PubMed1995

Comparison of triple dose versus standard dose gadolinium-DTPA for detection of MRI enhancing lesions in patients with primary progressive multiple sclerosis.

This study was performed to evaluate whether a triple dose of gadolinium-DTPA (Gd-DTPA) increases the sensitivity of brain MRI for detecting enhancing lesions in patients with primary progressive multiple sclerosis (PPMS). T1 weighted brain MRI was obtained for 10 patients with PPMS in two sessions. In the first session, one scan was obtained five to seven minutes after the injection of 0.1 mmol/kg Gd-DTPA (standard dose). In the second session, six to 24 hours later, one scan before and two scans five to seven minutes and one hour after the injection of 0.3 mmol/kg Gd-DTPA (triple dose) were obtained. Four enhancing lesions were detected in two patients when the standard dose of Gd-DTPA was used. The numbers of enhancing lesions increased to 13 and the numbers of patients with such lesions to five when the triple dose of Gd-DTPA was used and to 14 and six in the one hour delayed scans. The mean contrast ratio for enhancing lesions detected with the triple dose of Gd-DTPA was higher than those for lesions present in both the standard dose (P < 0.0009) and the one hour delayed scans (P = 0.04). These data indicate that with a triple dose of Gd-DTPA many more enhancing lesions can be detected in patients with PPMS. This is important both for planning clinical trials and for detecting the presence of inflammation in vivo in the lesions of such patients.

Adult↗
PubMed1995

A magnetization transfer imaging study of normal-appearing white matter in multiple sclerosis.

We attempted to define the role of subtle changes in the normal-appearing white matter (NAWM) in the development of disability in multiple sclerosis (MS). Twenty-seven clinically definite MS patients with either relapsing-remitting or chronic-progressive courses and 10 sex- and age-matched controls entered the study. For each patient and control, we studied two NAWM areas in the frontal lobe with magnetization transfer imaging (MTI). For patients, we also calculated the MT ratios (MTRs) for three contiguous areas of NAWM progressively further from "isolated" lesions visible on conventional MRI. Frontal NAWM in MS patients had lower mean MTRs than the frontal white matter of the controls (p = 0.02). MTRs in the NAWM adjacent to isolated lesions increased with distance from them to the cortical gray matter (p = 0.04). This pattern was typical for patients with chronic-progressive MS whose MTRs in the first two regions of NAWM adjacent to lesions were lower than those of the same regions of patients with relapsing-remitting MS. This study confirms that there are alterations in the NAWM of MS patients and suggests that such changes might be relevant to the disability in MS.

Adult↗
PubMed1995

Spontaneous involution of optic pathway lesions in neurofibromatosis type 1: serial contrast MR evaluation.

PURPOSE: To evaluate with contrast MR the evolution in size, signal, and contrast enhancement of optic pathway lesions in four patients with neurofibromatosis type 1. METHODS: The four reported patients are children with ages ranging from 21 months to 13 years affected by neurofibromatosis type 1 and optic pathway lesions. No treatment of the optic pathway lesions was carried out in these patients. They have been followed by serial contrast MR. RESULTS: In all patients a change in size, signal, and enhancement of optic pathways lesions was noted with time, and in the last follow-up study a marked reduction in size and enhancement of optic pathway lesions was observed in all cases. CONCLUSIONS: Modification and regression of optic pathway lesions with spontaneous disappearance of the enhancement is demonstrated. This finding could have a crucial influence on the therapeutic approach of the optic pathway lesions.

Adolescent↗
PubMed1995

Acute transverse myelopathy: spinal and cranial MR study with clinical follow-up.

PURPOSE: To evaluate the contribution of MR in determining the cause of acute transverse myelopathy, to determine the frequency and types of the intracranial lesions detectable on MR at the onset of the disease, and to monitor clinical and MR evolution of the disease. METHODS: Spinal and cranial MR images were obtained for 30 patients with acute transverse myelopathy. Gadopentetate dimeglumine was administered in 10 patients. Mean follow-up time was 18 months. RESULTS: Spinal cord MR findings were abnormal in 14 of 30 patients. The abnormal MR can be divided into group A, in which one segment was involved (8 patients), and group B, in which more than one segment was involved (6 patients). In both groups there were 2 patients with enhancing lesions. Enhancement was less homogeneous in the group B patients. Enhancement did not change with increased length of lesion. At follow-up, the diagnostic categories of the patients were multiple sclerosis (8 patients), encephalomyelitis (1 patient), viral myelitis (3 patients), and myelopathy of unknown cause (18 patients). After the episode of acute transverse myelopathy, in 4 of 8 patients in group A and in 4 of 5 patients with normal spinal MR but abnormal brain MR findings clinical signs of multiple sclerosis developed. In no patients in group B did multiple sclerosis develop. The final diagnoses for the 4 patients with gadolinium-enhancing spinal lesions were myelopathy of unknown cause (2 patients), multiple sclerosis (1 patient), and viral myelitis (1 patient). CONCLUSION: MR contributed to establishing the diagnosis in 40% of our cases.

Acute Disease↗
PubMed1994

Early diagnosis of optic glioma in children with neurofibromatosis type 1.

Twenty-five asymptomatic patients with neurofibromatosis type 1 (NF 1), aged 6-21 years, underwent the following examinations: intracranial magnetic resonance testing (MRI), visual acuity testing, ophthalmoscopy, and visual field and pattern reversal visual evoked potentials (VEPs). MRI showed enlargement of one or both optic nerves in six children, with bilateral involvement in three. VEPs were normal in all these patients; two of them had abnormalities on other visual examinations, although there were no subjective visual disturbances. These results show that VEPs cannot be considered as a screening test for optic pathway lesions in children with NF 1, as previously stated, and that other types of visual function examination may be more sensitive. These data may contribute to the establishment of more precise guidelines for the evaluation and treatment of children with NF 1.

Adolescent↗
PubMed1994

Evidence of a congenital midline brain anomaly in pituitary dwarfs: a magnetic resonance imaging study in 101 patients.

BACKGROUND: Magnetic resonance imaging (MRI) of the brain in pituitary dwarfs has revealed a previously unknown entity: ectopia of the posterior pituitary (PPE), absence or hypoplasia of the pituitary stalk and hypoplasia of the anterior pituitary. The pathogenesis of these findings was explained originally by a traumatic transection of the pituitary stalk during delivery. A high incidence of breech delivery has been reported in these groups, but the traumatic hypothesis cannot explain the findings in the relatively high percentage of patients with normal delivery, nor account for a different feature also found in other pituitary dwarfs consisting of pituitary hypoplasia with normal posterior pituitary. A second hypothesis could then been proposed, based on dysgenesis or abnormal embryonic development of both adenohypophysis and neurohypophysis. OBJECTIVE: To review the value and significance of these two different etiopathogenetic hypotheses by analyzing clinical, endocrinological, and MRI findings in a large population of pituitary dwarfs. METHODS: One hundred and one consecutive patients with congenital idiopathic growth hormone deficiency (CIGHD) were studied by MRI; they were compared with a control group of 46 healthy short children. A complete clinico-endocrinological evaluation was obtained in both patients and controls to assess the perinatal history, the pituitary-hypothalamic function, and the neurological status. MRI studies were evaluated both qualitatively and quantitatively and the pituitary volume (PV) was calculated in both patients and controls. Quantitative data were statistically analyzed to compare the mean PV of the patients with the mean PV of controls, the hormonal therapy, the single or multiple pituitary hormone deficiency, and the presence of breech delivery. RESULTS: MRI revealed PPE in 59 patients and a normal posterior pituitary (NPP) in 42. PV was extremely small in patients with PPE and in patients with NPP associated with a severely narrowed pituitary stalk; mean PV was significantly lower in CIGHD patients when compared with that of healthy short children. PV was not influenced by hormonal therapy and did not differ between patients with single and multiple pituitary hormone deficiency and between patients with normal and breech delivery. PPE patients differed from NPP patients for a higher male/female ratio (3:1 vs 1:1) and for a greater frequency of multiple pituitary hormone deficiency (49% vs 12%), breech delivery (32% vs 7%), and associated congenital brain anomalies (12% vs 7%). In PPE patients breech delivery was strongly associated with multiple pituitary hormone deficiency. CONCLUSION: On the basis of this study the traumatic hypothesis could theoretically explain the pathogenesis of PPE only in 32% of the patients with this condition. On the basis of modern understanding of embryogenesis of anterior and posterior pituitary, it is then justified to propose that a defective induction of mediobasal structure of the brain in the early embryo could account for both the complex morphological MRI abnormality and the clinico-endocrinological features encountered in all PPE patients. The close contiguity between the future pituitary and hypothalamus, the peculiar association with congenital midline brain anomalies, and the recent data about a possible role of Pit-1 gene, all support the hypothesis of a congenital defect. Finally, breech delivery can be considered not as a cause of PPE, but as an effect of the embryonic pituitary-hypothalamic abnormalities.

Adolescent↗