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Alessandro Bozzao

Publications and source records attributed to Alessandro Bozzao.

13 recordsLinked to original sources
PubMed2004

Magnetic resonance imaging in Posterior Reversible Encephalopathy Syndrome: report of three cases and review of literature.

INTRODUCTION: Eclampsia is one of the main causes of Posterior Reversible Encephalopathy Syndrome (PRES) a recent clinico-neuroradiological entity represented by characteristic MR findings of a symmetric bilateral subcortical/cortical hyperintensity in T2-weighted images, more often in parieto-occipital lobes, accompanied by clinical neurological alterations. Neuroradiological and clinical alterations are commonly completely reversible although ischemic evolution has been described. The pathophysiology is still a matter of debate. Specific magnetic resonance (MR) techniques, such as FLAIR (fluid attenuated inversion recovery) and DWI (diffusion weighted images) sequences, have improved the ability to detect subcortical/cortical lesions and helped to clarify the underlying pathophysiological mechanism of cerebrovascular involvement, which results important for an appropriate therapeutic decision. CASE REPORT AND DISCUSSION: We report the MR imaging findings of three patients with eclampsia and PRES as well as a careful review of literature.

Adult↗
PubMed2004

Increased brain apparent diffusion coefficient in tuberous sclerosis.

PURPOSE: To evaluate the water diffusivity of normal-appearing white matter (NAWM) in patients with tuberous sclerosis complex compared with that in control subjects. MATERIALS AND METHODS: Diffusion and conventional magnetic resonance (MR) imaging examinations were performed in 18 patients with clinically established tuberous sclerosis complex (10 male and eight female patients; mean age, 20.1 years; range, 12-30 years), as well as in 18 age-matched control subjects (nine male and nine female; mean age, 20.2 years; range, 11-28 years). Apparent diffusion coefficients (ADCs) were generated, and small elliptic regions of interest were manually placed both in perilesional NAWM and in six anatomic locations of NAWM remote from hamartomatous lesions. Perilesional ADCs were compared with those at the same anatomic site on the contralateral side of the brain (generalized linear regression analysis). ADCs from the predetermined sites in patients were compared with those in control subjects (generalized linear regression analysis). RESULTS: Supratentorial ADCs were higher in patients with tuberous sclerosis complex than in control subjects, and statistically significant differences were observed in the occipital white matter, frontal white matter, centrum semiovale, parietal white matter, and corona radiata (for each location, P <.001). Significant increases were also seen in the perilesional NAWM compared with NAWM at the same anatomic locations on the contralateral side (P <.001). Infratentorial ADCs were normal. CONCLUSION: Significant ADC increases were measured in the supratentorial NAWM.

Adolescent↗
PubMed2004

Evaluation of anterior pituitary gland volume in childhood using three-dimensional MRI.

BACKGROUND: Three-dimensional MRI (3D-MRI) is a reliable tool for the evaluation of anatomical volumes. Volumetric measurement of the normal anterior pituitary gland in childhood has been performed in the past by 2D-MRI calculations, but has inherent inaccuracies. OBJECTIVE: To obtain accurate normal anterior pituitary gland volume in childhood using 3D-MRI coronal sections. MATERIALS AND METHODS: The anterior pituitary gland was measured using coronal T1-weighted 3D-gradient-echo sequences (section thickness 0.75 mm). The study group was composed of 95 prepubertal children (age range 2 months-10 years) with clinically normal pituitary function and no pituitary or brain abnormalities. RESULTS: A measurement error of 0.2-0.4% was assessed by using a phantom study. Volumetric evaluation of the anterior pituitary gland showed progressive growth of the gland from a mean 131+/-24 mm(3) at 2-12 months, to 249+/-25 mm(3) at 1-4 years and 271+/-29 mm(3) at 5-10 years. CONCLUSIONS: These data may be useful for paediatricians in the evaluation of patients with neuroendocrine diseases, in particular growth hormone deficiency.

Analysis of Variance↗
PubMed2004

Neonatal identification of pituitary aplasia: a life-saving diagnosis. Review of five cases.

BACKGROUND: Neonatal onset hypopituitarism is a life-threatening, potentially treatable endocrine disease. A possible cause is congenital absence of the anterior pituitary gland, a condition very rarely reported in the literature. METHODS: A series of 5 cases of children with pituitary aplasia referred to the Centre of Paediatric Endocrinology 'Rina Balducci', Tor Vergata University, Rome, is presented. RESULTS: Major clinical features in our patients were respiratory distress on the first day of life, in spite of uneventful pregnancy, labour and delivery, metabolic acidosis, non-cholestatic jaundice, hypotonia, severe hypoglycaemia, hypogenitalism, and midline defects. Diagnosis was established by endocrine tests during hypoglycaemia and hypothalamic-pituitary MRI scan. Symptoms disappeared soon after replacement therapy was started. CONCLUSION: We stress the importance of performing baseline endocrine tests as soon as possible during hypoglycaemia and MRI of the brain aimed at visualizing the hypothalamic-pituitary area in neonates with hypogenitalism and severe unexplained hypoglycaemia, so that the irreversible neurological and developmental consequences of panhypopituitarism can be prevented by adequate replacement therapy.

Brain↗
PubMed2003

Syringomyelia associated with hydrocephalus and Blake's pouch cyst: case report.

STUDY DESIGN: This is a case report of a 37-year-old woman who sought treatment for a large syringomyelic cavitation extending from C3 to the entire medulla, a tetraventricular hydrocephalus, and a cystic cavitation in the posterior cranial fossa communicating with the fourth ventricle (Blake's pouch cyst). The patient underwent a decompressive craniectomy, a C1 laminectomy, and the opening of the cysts to enable communication with the subarachnoid spaces. After an initial period of symptom remission, reassured by the magnetic resonance images indicating a reduction of the syringomyelia, the patient's neurologic conditions deteriorated because of further dilation of the ventricular cavities, which was resolved by the insertion of a ventriculoperitoneal shunt. OBJECTIVE: To suggest the treatment of choice in a patient with syringomyelia and hydrocephalus caused by Blake's pouch cyst. SUMMARY OF BACKGROUND DATA: Blake's pouch cyst is an entity often poorly understood, deriving from nonperforation of the primitive foramen of Magendie, causing a precarious equilibrium of the cerebrospinal fluid flow resulting from a defect in communication between the fourth ventricle and the encephalic and spinal subarachnoid spaces. Authors report the association of Blake's pouch cyst with cervicodorsal syringomyelia and tetraventricular hydrocephalus. METHODS: A case of syringomyelia associated with hydrocephalus and Blake's pouch cyst is described. RESULTS: Symptoms of syringomyelia and hydrocephalus disappeared only after positioning of a ventriculoperitoneal shunt. CONCLUSIONS: The treatment of choice for a case of syringomyelia associated with Blake's pouch cyst and hydrocephalus is the application of a ventriculoperitoneal shunt or, even better, an endoscopic third ventriculostomy.

Adult↗
PubMed2003

Diffusion-weighted MR imaging in the early diagnosis of periventricular leukomalacia.

Diffusion-weighted imaging (DWI) has been shown to be highly sensitive in detecting acute cerebral infarction, but its use in detecting hypoxic-ischemic encephalopathy (HIE) in neonates is still controversial. Moreover, few reports concern pre-term infants with possible periventricular leukomalacia (PVL). We examined the ability of this technique to detect cerebral changes in the acute phase of PVL. Fifteen MR examinations were performed in 11 pre-term infants (mean age 3.4 days, range 2-6 days). Conventional DWI sequences, apparent diffusion coefficient (ADC) maps, and US obtained in the acute phase were compared. All the neonates underwent US follow-up up to 4 months after delivery; those with suspected PVL also underwent MRI follow-up for up to 2 months. Qualitative and quantitative evaluations were performed to assess the presence of DW changes compatible with PVL. Diffusion-weighted MRI showed signal hyperintensity associated with decreased ADC values in 3 subjects (27%). In these patients conventional MRI sequences were interpreted as normal and US (performed at the same time) as doubtful in 2 and compatible with PVL in 1 subject. The MRI and US follow-up confirmed severe damage in all these patients. In 1 neonate hemorrhages involving the germinative matrix were identified. In 8 neonates MRI was considered normal. In these subjects US follow-up (up to 4 months) confirmed no signs of PVL. Diffusion-weighted imaging may have a higher correlation with later evidence of PVL than does conventional MR imaging and US when performed in the acute phase of the disease.

Brain↗
PubMed2003

Quantitative EEG and dynamic susceptibility contrast MRI in Alzheimer's disease: a correlative study.

OBJECTIVE: To investigate the relationship between the electroencephalographic (EEG) power spectra features obtained by quantitative EEG (qEEG) and the hemodynamic parameters detected by dynamic susceptibility contrast-enhanced MR imaging (DSC MRI) in patients with Alzheimer's disease (AD). METHODS: Fourteen patients with probable AD and 15 elderly healthy controls were included in the study. All subjects underwent both EEG recording in a rest condition and perfusion MRI. Three EEG scalp areas were defined (anterior, central and posterior) and power spectra values were obtained from each scalp area. Relative values of temporoparietal and sensorimotor regional cerebral blood volume (rCBV) were measured bilaterally and successively averaged to obtain a total perfusion index. The brain atrophy index was calculated and used as a covariate to rCBV. Correlation analysis was performed between EEG variables and hemodynamic-morphological parameters. RESULTS: qEEG power spectra of AD patients were characterized by an increase in mean relative power of theta (4-7.75 Hz) associated with a decrease in alpha (8-12.75 Hz) frequency bands with a topographic distribution over the central and posterior EEG scalp regions, when compared with controls; beta (13-31 Hz) frequency band also displayed a significant decrease over the anterior and posterior EEG scalp regions of AD patients with respect to controls. The DSC MRI revealed a bilateral reduction in the temporoparietal and sensorimotor rCBV with respect to controls. Correlation analysis showed that the total level of hypoperfusion selectively correlates with the EEG power spectra in theta and alpha frequency bands distributed over anterior/central and central region, respectively. Within AD patients, the lower the level of hypoperfusion, the higher the content of EEG power spectra in theta frequency band, and the lower the level of hypoperfusion, the lower the content of EEG power spectra in alpha band. CONCLUSIONS: The combined qEEG and DSC MRI technology unveiled a selective correlation between neurophysiological and hemodynamical patterns in AD patients. Further investigations will ascertain the relevance of this multi-modal approach in the heterogeneous clinical context of AD.

Aged↗
PubMed2002

Cerebrospinal fluid changes after intravenous injection of gadolinium chelate: assessment by FLAIR MR imaging.

Fluid-attenuated inversion recovery (FLAIR) sequence is currently used in clinical practice. Some reports emphasize the possibility that, in pathologic conditions, intravenous injection of gadolinium chelates may lead to an increased signal inside the cerebrospinal fluid (CSF). The aim of this study was to evaluate the presence of CSF signal changes in pathologic conditions causing blood-brain barrier disruption or neovascularization when imaging is performed after intravenous injection of gadolinium. We obtained FLAIR sequences after gadolinium injection from 33 patients affected by different intracranial pathologies and 10 control subjects. Patients were affected by ischemic stroke in the subacute phase, from 2 to 7 days from onset of symptoms (12 patients), meningiomas (8 patients), high-grade gliomas (5 patients), previous surgical procedures for intra-axial neoplasms (5 patients), and multiple sclerosis with active plaques (3 patients). Magnetic resonance imaging was performed in patients and controls using a 1.5-T magnet, using T2- and T1-weighted FLAIR sequences. The FLAIR sequence was acquired before and 1-3 h after injection of a standard dose of gadolinium. In those patients affected by ischemic lesions, FLAIR sequences were repeated the next days and 3-4 days later. The CSF signal was visually evaluated by two readers and scored from 0 to 3 depending by the degree of enhancement. The location of CSF signal changes (close to the lesion, hemispheric, or diffuse) was also considered. The CSF signal was markedly increased after 3 h from intravenous injection of gadolinium in all the patients with stroke, in those with previous surgery, and in those with high-grade gliomas whose neoplasm's surface was in contact with the subarachnoid spaces (SAS) or ventricles; a strong enhancement was also evident inside the necrotic component of the tumor. The CSF changes were more evident close to the pathology and/or in the hemisphere involved by the pathology. Moderate CSF enhancement was observed in the SAS close to meningiomas. No signal changes were evident in all the others. In those patients with stroke imaged in the following days, CSF signal showed to be diffuse to both hemispheres the next day and returned to normal values within 2 days. In patients affected by pathologies with blood-brain barrier breakdown or neovascularization close the SAS or the ventricles, CSF changes, related to gadolinium leakage, are likely when FLAIR sequences are acquired 2-24 h after i.v. injection of the contrast. This pattern should be known in order to differentiate it from that of subarachnoid hemorrhage.

Aged↗
PubMed2002

Dynamic susceptibility contrast (DSC) MRI and interictal epileptiform activity in cryptogenic partial epilepsy.

PURPOSE: To study the possible correlation between interictal EEG patterns and neuroradiologic data obtained by dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) in patients with partial epilepsy. METHODS: Seventeen subjects with cryptogenic partial epilepsy underwent long-term video-EEG monitoring and DSC-MRI in the same session. Ten patients had temporal lobe epilepsy (TLE) and seven, epilepsy of extratemporal origin (ExTE). MRI data were compared with EEG findings, and the accuracy of DSC-MRI was analyzed considering spiking rate (number of interictal epileptiform abnormalities, IEA/min) and type of epilepsy. RESULTS: DSC-MRI showed a relevant asymmetry in the frontal, temporal, and occipital regions in eight (47%) of 17 patients, consisting of a relative regional cerebral blood volume (rCBV) increase in these areas. Because this region corresponded to the interictal EEG focus (IEF) or to the hemisphere involved in the genesis of epileptic discharges in most patients showing a higher spiking rate, patients were classified in two groups: patients with high spiking rate (HSR, n = 9) and with low spiking rate (LSR, n = 8); the cutoff corresponded to the median value of IEA/min. The rCBV increase corresponded to the IEF or to the hemisphere involved in the genesis of epileptic discharges in seven (77.7%) of nine HSR patients. No patients with LSR showed significant asymmetries in rCBV pattern. In five of six patients with TLE-HSR (83.3%), DSC-MRI showed a relative rCBV increase concordant with IEF or hemisphere involved in the genesis of epileptic discharges; in patients with ExTE-HSR, the concordance was 66%. CONCLUSIONS: DSC-MRI is a noninvasive procedure that may provide useful additional information to lateralize and/or localize the IEF when interictal epileptiform activity is sufficiently elevated.

Adolescent↗
PubMed2002

Hemodynamic modifications in patients with symptomatic unilateral stenosis of the internal carotid artery: evaluation with MR imaging perfusion sequences.

BACKGROUND AND PURPOSE: Risk of developing ischemia is higher in patients with reduced cerebrovascular reactivity than in those with preserved cerebrovascular reactivity. Therefore, we assessed cerebral hemodynamic modifications in patients with unilateral stenosis of the internal carotid artery by using perfusion-weighted MR imaging to determine if these modifications underlie or anticipate ischemic signs and symptoms. METHODS: Fifteen patients with unilateral 70-90% carotid artery stenosis were studied with digital subtraction angiography and perfusion-weighted MR imaging. Their findings were compared with those of 15 age- and sex-matched control subjects. Regional cerebral blood volume (rCBV) and mean transit time (MTT) values were calculated in the middle cerebral artery and border zone territories. RESULTS: No significant difference was noted in rCBV and MTT values between the hemispheres in the symptomatic patients. There was a significant difference in MTT values in the border zones between patients and control subjects. MR images in patients and control subjects did not reveal large territorial infarcts and did reveal similar white matter lesion burdens. CONCLUSION: There is adequate compensation of unilateral stenosis when the stenosis is less than 90%. The risk of stroke is higher in patients with stenoses exceeding 70%, mostly because of decreased collateral reserve when confronted with emboli.

Aged↗
PubMedDate not supplied

Epidural hematoma after thoracic epidural catheter removal in the absence of risk factors.

BACKGROUND AND OBJECTIVES: The purpose of this report is to enhance awareness that an epidural hematoma can occur even in patients devoid of risk factors. CASE REPORT: A 69-year-old, 55-kg male was scheduled for video-assisted thoracoscopic resection of bilateral pulmonary metastases and received combined thoracic epidural and general anesthesia. The epidural catheter insertion was unremarkable. All laboratory values were within normal values. No anticoagulation or antiplatelet drugs were administered. The epidural catheter was removed on postoperative day 2. The patient developed signs of an epidural hematoma a few hours later and was treated by decompressive laminectomy. Full neurologic recovery was observed after a 6-month period. CONCLUSION: Catheter removal is a critical period for epidural hematoma formation even if no risk factors are identified. Early recognition and treatment are essential features for good neurologic recovery after an epidural hematoma.

Aged↗
PubMedDate not supplied

Diffusion-weighted MR Imaging: clinical applications in neuroradiology.

Among functional magnetic resonance imaging techniques, diffusion-weighted imaging (DWI) plays an important role in the assessment of a wide variety of brain diseases. DWI provides image contrast that depends on the molecular motion of water and it can be easily added to a standard cranial MR examination, with limited increase in time (imaging time ranges from a few seconds to 2 minutes). DWI is particularly sensitive in the detection of acute ischaemic stroke and in monitoring its evolution (also in the light of new therapeutic strategies for early treatment). Diffusion-weighted MR imaging also provides adjunctive information in the differential diagnosis of other brain diseases including neoplasms, intracranial infections, traumatic brain injury and demyelination some of which may manifest with sudden neurological deficits mimicking acute ischaemic stroke.

Acute Disease↗