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Lymphomatosis cerebri (LC) is a rare form of primary central nervous system lymphoma; we report a case of LC mainly involving the brainstem and cerebellum. This diagnosis should be considered in patients presenting with diffuse white matter disease, and a subacute clinical history of cognitive deficits, ataxic gait, and personality changes. We present our findings along with a review of the neuroradiological literature.

Myotonic dystrophy type 1 (DM1) is a multisystemic disease involving multiple organ systems including central nervous system (CNS) and muscles. Few studies have focused on the central motor system in DM1, pointing to a subclinical abnormality in the CNS. The aim of our study was to investigate patterns of cerebral activation in DM1 during a motor task using functional MRI (fMRI). Fifteen DM1 patients, aged 20 to 59 years, and 15 controls of comparable age were scanned during a self-paced sequential finger-to-thumb opposition task of their dominant right hand. Functional MRI images were analyzed using SPM99. Patients underwent clinical and genetic assessment; all subjects underwent a conventional MR study. Myotonic dystrophy type 1 patients showed greater activation than controls in bilateral sensorimotor areas and inferior parietal lobules, basal ganglia and thalami, in the ipsilateral premotor area, insula and supplementary motor area (corrected P

We describe a case of neuroplasticity associated with both arteriovenous malformation (AVM) and stroke, which occurred in two successive events in the same patient. Functional magnetic resonance imaging (fMRI) during right-hand movement in a young man with a left rolandic AVM detected activation of a region corresponding to the left premotor cortex. The AVM was embolized. A few hours after the last embolization session, the patient sustained an ischemic complication in the left subcortical white matter. A second fMRI detected a lower degree of left premotor cortex activation and strong activation of the contralesional right primary motor cortex and bilateral supplementary motor areas. One month later, in association with clinical recovery, the fMRI activation returned to that observed in the first fMRI, ie, selective activation of the ipsilesional left premotor cortex. This is, to our knowledge, the first description of two distinct functional cortical changes determined by an AVM and a stroke within the motor network.

The purpose of this study was to investigate short-time metabolic variations related to continuous epileptic activity elicited by fixation-off sensitivity (FOS). Time-resolved magnetic resonance spectroscopy was performed on a patient on whom previous clinical findings clearly indicated presence of FOS. The epileptic focus was localized with a simultaneous electroencephalographic and functional magnetic resonance imaging study. The results showed a linear increase of the sum of glutamate and glutamine with time of paroxysmal activity in epileptic focus and much greater concentration of choline-containing compounds in focus than in the contralateral side.

Using functional MRI (fMRI), patients with multiple sclerosis showed a greater extent of motor activation than controls. Although functional changes are often interpreted as adaptive and as a contributing factor in limiting the clinical deficit, no longitudinal studies have yet been performed for multiple sclerosis. Sixteen patients with multiple sclerosis, two patients with possible multiple sclerosis and nine age-matched controls underwent two fMRI studies with a time interval of 15-26 months. The motor task consisted of a self-paced sequential finger opposition movement with the right hand. Patients with multiple sclerosis exhibited greater bilateral activation than controls in both fMRI studies. At follow-up, patients showed a reduction in functional activity in the ipsilateral sensorimotor cortex and in the contralateral cerebellum. No significant differences between the two fMRI studies were observed in controls. Activation changes in ipsilateral motor areas correlated inversely with age, extent and progression of T1 lesion load, and occurrence of a new relapse. This study may help the understanding of the evolution of brain plastic changes in multiple sclerosis indicating that, in younger patients with a less structural brain damage and benign clinical course, the brain reorganizes its functional activity towards a more lateralized pattern of brain activation. The tendency towards a normalization of brain functional activity is hampered in older patients and in those developing relapses or new irreversible brain damage.

Several cystic lesions may involve the temporal lobe including arachnoid, choroidal fissure and juxta-sylvian cysts. We reported a case of appearance, increase and spontaneous disappearance of a juxta-sylvian cyst in a young girl with headache studied by MRI between 1990 and 2003. In agreement with previous reports, the sudden disappearance, without a history of trauma, could be the result of an osmotic effect that shifted CSF inside the cyst, leading to an increase in osmotic pressure and rupture of the cyst wall.

A standard EEG equipment was modified in order to work properly during ultra-fast MRI acquisitions. Changes include: amagnetic electrode cap, optical fiber link, shielding box for EEG amplifier, twisted low metal mass cable. The effects of the RF pulse and time varying magnetic fields were minimized by using a correct head cap wires locked environment montage and then removed with a simple subtraction algorithm during EEG/fMRI acquisition. Ballistocardiogram artifact was also minimized at suitable levels by using a comfortable head position and immobilization.

Functional magnetic resonance imaging (fMRI) data on motor function have shown adaptive functional changes related to brain injury in multiple sclerosis (MS). We investigated whether patients with MS have altered fMRI activation patterns during attention and memory tasks, and whether functional changes in the brain correlate with the extent of overall tissue damage on conventional MRI. Twenty-two right-handed patients with relapsing-remitting MS (RRMS) and no or only mild deficits at neuropsychological testing and 22 matched healthy subjects were scanned during the Paced Auditory Serial Addition Test (PASAT) and a recall task. fMRI data were analyzed using Statistical Parametric Mapping (SPM99). The relation between fMRI changes during both tasks and T2 lesion load was investigated. During both tasks, patients exhibited significantly greater brain activation than controls and recruited additional brain areas. Task-related functional changes were more significant in patients whose performance matched that of controls than in patients with a lower performance. During the PASAT, brain functional changes involved the right supplementary motor area and cingulate, the bilateral prefrontal, temporal and parietal areas, whereas during the recall task they involved the prefrontal and temporal cortex and basal ganglia bilaterally, and the left thalamus. In patients, activation in specific brain areas during performance of both tasks positively correlated with T2 brain lesions. Patients with RRMS exhibit altered patterns of activation during tasks exploring sustained attention, information processing and memory. During these tasks, fMRI activity is greater in patients with better cognitive function than in those with lower cognitive function. Functional changes in specific brain areas increase with increasing tissue damage suggesting that they may also represent adaptive mechanisms that reflect underlying neural disorganization or disinhibition, possibly associated with MS.

The objectives of this study were to assess whether cortical motor reorganization in the early phase of multiple sclerosis (MS) is correlated with the clinical presentation and with specific damage to the corticospinal tract. Twenty patients with clinically isolated syndrome (CIS) and serial MR findings indicative of MS were selected. In 10 patients the CIS was hemiparesis (group H), and in 10 patients the CIS was optic neuritis (group ON). There were no significant differences in age, disease duration, total T2 lesion load (LL), and total T1 LL between group H and group ON. Ten age-matched healthy subjects served as controls (group C). All subjects were submitted to fMRI during a sequential finger-to-thumb opposition task of the right hand. Group H showed a significantly higher EDSS score and T1 LL calculated along the corticospinal tract than group ON. Three-group comparison by ANOVA showed significantly higher activation in group H than in the other two groups (P < 0.001). Significant foci were located in the sensory-motor cortex (BA 1-4), the parietal cortex (BA 40), the insula of the ipsilateral hemisphere, and the contralateral motor cortex (BA 4/6). Group ON showed, although at a lower level of significance (P < 0.01), higher activation of the contralateral motor-related areas than group C. Multiple regression analysis showed that T2 and T1 LL along the corticospinal tract and time since clinical onset positively correlated with activation in motor areas in both cerebral hemispheres (P < 0.005). Total T2 LL positively correlated with activation in motor areas in the contralateral hemisphere (P < 0.005). Total T1 LL and EDSS did not show any significant correlation. More severe specific damage to the motor pathway in patients with previous hemiparesis may explain the significantly higher involvement of ipsilateral motor areas observed in group H than in group ON. Furthermore, the significant correlation between the time since clinical onset and activation in motor areas suggests that cortical reorganization develops gradually in concomitance with the subclinical accumulation of tissue damage.

Using functional MRI (fMRI) with concurrent EEG monitoring the authors studied cortical activation associated with epileptiform discharges in three patients with fixation-off sensitivity. The EEG paroxysmal activity elicited by eliminating central vision correlated significantly with an increased blood oxygen level-dependent signal in the extrastriate cortex (Brodmann areas 19 and 37). fMRI provides a unique opportunity for localizing precisely the cortical areas generating paroxysmal activity in patients with fixation-off sensitivity.

Background and Purpose —The term symptomatic hemorrhage secondary to ischemic stroke implies a clear causal relationship between clinical deterioration and hemorrhagic transformation (HT) regardless of the type of HT. The aim of this study was to assess which type of HT independently affects clinical outcome. Methods —We used the data set of the European Cooperative Acute Stroke Study (ECASS) II for a post hoc analysis. All patients had a control CT scan after 24 to 96 hours or earlier in case of rapid and severe clinical deterioration. HT was categorized according to radiological criteria: hemorrhagic infarction type 1 and type 2 and parenchymal hematoma type 1 and type 2. The clinical course was prospectively documented with the National Institutes of Health Stroke Scale and the modified Rankin Scale. The independent risk of each type of HT was calculated for clinical deterioration at 24 hours and disability and death at 3 months after stroke onset and adjusted for possible confounding factors such as age, severity of stroke syndrome at baseline, and extent of the ischemic lesion on the initial CT. Results —Compared with absence of HT, only parenchymal hematoma type 2 was associated with an increased risk for deterioration at 24 hours after stroke onset (adjusted odds ratio, 18; 95% CI, 6 to 56) and for death at 3 months (adjusted odds ratio, 11; 95% CI, 3.7 to 36). All other types of HT did not independently increase the risk of late deterioration. Conclusions —Only parenchymal hematoma type 2 independently causes clinical deterioration and impairs prognosis. It has a distinct radiological feature: it is a dense homogeneous hematoma >30% of the ischemic lesion volume with significant space-occupying effect.

Negli ultimi anni, grazie allo sviluppo nel campo della tecnologia ultraveloce e ad una migliore comprensione dei principi fisici che regolano l'azione dei mezzi di contrasto per RM, è stata introdotta una modalità di imaging funzionale completamente nuova, la RM funzionale. Le tecniche funzionali permettono l'acquisizione di mappe dei principali parametri emodinamici (RM di perfusione o PWI), la valutazione della mobilità delle molecole d'acqua (RM di diffusione o DWI) e lo studio delle attivazioni neuronali (fMRI). La combinazione delle diverse tecniche funzionali permette di valutare nello stesso esame aspetti diversi e complementari della fisiopatologia cerebrale e di combinarli con le informazioni fornite dall'acquisizione di immagini convenzionali. Per questo motivo per la disponibilità commerciale delle tecniche ultraveloci, le tecniche di RM funzionale, in un primo momento applicate prevalentemente a scopo di ricerca, sono state gradualmente introdotte nella pratica clinica. In questo lavoro illustreremo brevemente i principi fisici alla base delle tecniche di diffusione e perfusione e le loro principali applicazioni cliniche. In recent years, advances in ultrafast technology and a better understanding of the physical principles underlying the effect of MR contrast media have given rise to a new functional imaging technique, functional magnetic resonance. Functional techniques allow the acquisition of maps of the main haemodynamic parameters (perfusion MR or PWI), evaluation of the mobility of water molecules (diffusion MR or DWI) and the study of neuronal activation (fMRI). The combination of different functional techniques allows assessment of different complementary aspects of brain pathophysiology during the same examination so that they can be combined with information provided by conventional scans. Following the advent of ultrafast techniques, functional MR imaging initially confined to research has gradually been introduced into clinical practice. This paper briefly described the physical principles underlying the diffusion and perfusion techniques and their main clinical applications.

La RM di diffusione (DWI) e perfusione (PWI) sono da considerarsi tecniche di elezione nello studio dell'ischemia acuta nell'uomo. La DWI permette infatti di evidenziare il danno tissutale dovuto all'ischemia già dopo pochi minuti dall'insulto ischemico. La PWI, d'altra parte, offre la possibilità di valutare l'emodinamica cerebrale e di evidenziare, quindi, aree non ancora danneggiate, ma a rischio di evolvere verso l'infarto. L'uso combinato di queste due metodiche di indagine permette il giusto inquadramento del paziente con ictus ischemico acuto, da un punto di vista prognostico e terapeutico. I dati della letteratura sono riportati e interpretati, sulla base dell'esperienza personale.

Using functional MRI (fMRI), we have studied the changes induced by the performance of a complex sequential motor task in the cortical areas of six akinetic patients with Parkinson's disease and six normal subjects. Compared with the normal subjects, the patients with Parkinson's disease exhibited a relatively decreased fMRI signal in the rostral part of the supplementary motor area (SMA) and in the right dorsolateral prefrontal cortex, as previously shown in PET studies. Concomitantly, the same patients exhibited a significant bilateral relative increase in fMRI signal in the primary sensorimotor cortex, lateral premotor cortex, inferior parietal cortex, caudal part of the SMA and anterior cingulate cortex. These fMRI data confirm that the frontal hypoactivation observed in patients with Parkinson's disease is restricted to the rostral part of the SMA and to the dorsolateral prefrontal cortex. These results also show that, apart from the lateral premotor and parietal cortices, increased fMRI signals can be found in other cortical motor areas of these patients, including the posterior SMA, the anterior cingulate cortex and the primary sensorimotor cortices, which are then likely to participate in the same putative attempt by the dopamine-denervated brain to recruit parallel motor circuits in order to overcome the functional deficit of the striatocortical motor loops.

In order to evaluate the clinical usefulness of emergency computed tomography (CT) in acute ischemic stroke, we assessed whether CT findings within the first few hours of stroke onset reliably predict type, site and size of the index infarction, and risk of death or disability. For this reason we reviewed clinical and CT findings in a cohort of unselected consecutive patients referred to the stroke unit of a large urban hospital because of a presumed ischemic stroke in the anterior circulation (AC), and submitted to CT within 5 h from onset. Out of 158 total patients, emergency CT revealed parenchymal changes compatible with AC focal ischemia in 77 (49%) and a hyperdense middle cerebral artery (MCA) in 41 (26%). Parenchymal changes and hyperdense MCA predicted an AC territorial infarction respectively in 97% of cases (95% C.I. 93% to 100%) and in 95% of cases (95% C.I. 88% to 100%). Site and size of early changes coincided with those of final lesions in 79% of patients with cortical changes and in 95% of patients with cortico-subcortical changes, but only in 37% of patients with initial subcortical changes, the remainder of whom developed a cortico-subcortical infarction. At logistic regression parenchymal changes were the only independent predictor of an AC territorial infarction. Negative predictive power, however, was only 40% (95% C.I. 29% to 51%) for parenchymal changes, and 35% for hyperdense MCA (95% C.I. 26% to 44%). The odds for death or disability at 1 month associated with parenchymal changes were thrice as high as with negative CT, even after adjustment for clinical severity on admission. These results indicate that CT scan adds significantly to the prediction of outcome made on clinical grounds. The frequent development of a territorial infarction in patients with initially negative CT and the subsequent recruitment of the cortex in those initially exhibiting only subcortical changes suggest that the transition from ischemia to infarction often occurs after the first five h following stroke.

Background and Purpose —The hyperdense middle cerebral artery sign (HMCAS) is a marker of thrombus in the middle cerebral artery. The aim of our study was to find out the frequency of the HMCAS, its association with initial neurological severity and early parenchymal ischemic changes on CT, its relevance to clinical outcome, and the efficacy of intravenous recombinant tissue plasminogen activator (rtPA) in patients with the HMCAS. Methods —Secondary analysis of the data from 620 patients who received either rtPA or placebo in the European Cooperative Acute Stroke Study I (ECASS I), a double-blind, randomized, multicenter trial. The baseline CT scans were obtained within 6 hours from the onset of symptoms. Functional and neurological outcomes were assessed using the modified Rankin Scale and the Scandinavian Stroke Scale at day 90. Results —We found an HMCAS in 107 patients(17.7%). The initial neurological deficit was more severe in patients with the HMCAS than in those lacking this sign ( P P P P =0.0297). Conclusions —The HMCAS is associated with severe brain ischemia and poor functional outcome. However, it has no significant independent prognostic value when accounting for the effect of initial severity of neurological deficit and of early parenchymal ischemic changes on CT. Patients with the HMCAS may benefit from intravenous rtPA.

Scopo del lavoro è stato quello di valutare eventuali alterazioni della intensità di segnale e di volume della regione ippocampale in pazienti affetti da epilessia temporale farmaco-resistente utilizzando sequenze Turbo-FLAIR (Fluid Attenuated Inversion Recovery) e sequenze volumetriche pesate in T1. A tale scopo abbiamo studiato 40 pazienti affetti da epilessia temporale farmaco-resistente utilizzando un apparecchio RM da 1,5 TESLA (NT 15 Philips «Gyroscan»). Sono state utilizzate sequenze Spin-Echo convenzionali, Turbo Spin-Echo, Inversion Recovery, Turbo-FLAIR e sequenze 3D volumetriche sui piani coronali, sequenze Spin-Echo convenzionali sui piani assiali e sagittali. L'intensità del segnale ed il volume della regione ippocampale sono stati valutati mediante analisi semi-quantitative automatiche eseguite con una workstation SUN. Abbiamo riscontrato una differenza significativa dei valori dell'intensità di segnale dei due ippocampi in 22 pazienti utilizzando le sequenze FLAIR. In 8 di questi pazienti non erano invece presenti differenze significative con le sequenze Spin-Echo convenzionali e Turbo Spin-Echo. L'analisi volumetrica ha mostrato un assottigliamento della corteccia dell'ippocampo in 12 dei 22 pazienti che presentavano anomalie dell'intensità del segnale. I dati del presente studio suggeriscono una maggiore sensibilità delle sequenze Turbo-FLAIR nell'evidenziare alterazioni dell'intensità di segnale della regione dell'ippocampo.

The aim of this study was to investigate whether a concomitant treatment with recombinant interferon beta 1a (rIFN beta-1a) modifies the effect of steroids on the blood-brain barrier (BBB) in relapsing remitting MS patients, as evaluated by enhanced MRI of the brain. We evaluated 19 patients with a clinical relapse treated only with intravenous methylprednisolone (IVMP; 1 g daily for 6 days), and 10 patients who experienced a clinical relapse and were treated with IVMP (1 g daily for 6 days) during an rIFN beta-1a treatment period. The number and volume of enhancing lesions were analyzed on four serial MR images obtained at monthly intervals (one scan before and three scans after IVMP treatment). A significant reduction in the mean number and volume of enhancing lesions was seen in the first scan after IVMP treatment in all patients. However, while persistently low enhancement was seen in the follow-up scans of patients treated with rIFN beta-1a, a rebound effect (i.e., increase in the number and volume of gadolinium-enhancing lesions) was observed in the other patients during the follow-up. These data suggest that rIFN beta-1a prolongs the beneficial effect of steroids on the BBB.

To determine whether the extent of subtle parenchymal hypoattenuation detected on computed tomographic (CT) scans obtained within 6 hours of ischemic stroke is a factor in predicting patients' response to thrombolytic treatment.The baseline CT scans of 620 patients, who received either recombinant tissue plasminogen activator (rt-PA) or a placebo, in a double-blind, randomized multicenter trial were prospectively evaluated and assigned to one of three categories according to the extent of parenchymal hypoattenuation: none, 33% or less (small), or more than 33% (large) of the middle cerebral artery territory. The association between the extent of hypoattenuation on the baseline CT scans and the clinical outcome in the placebo-treated and the rt-PA-treated groups after 3 months was analyzed.In 215 patients with a small hypoattenuating area, treatment increased the chance of good outcome. In 336 patients with a normal CT scan and in 52 patients with a large hypoattenuating area, rt-PA had no beneficial effect but increased the risk for fatal brain hemorrhage.The response to rt-PA in patients with ischemic stroke can be predicted on the basis of initial CT findings of the extent of parenchymal hypoattenuation in the territory of the middle cerebral artery.

The potential role of magnetic resonance imaging (MRI) in differentiating between specific causes of cognitive decline in patients with vascular dementia (VD) has not yet been fully established. We therefore decided to assess the supratentorial cerebral contents in 24 patients with a diagnosis of probable VD and in 24 normal subjects, matched for age and education level, using MRI volumetric parameters obtained by means of a quantitative method. The volumes of subarachnoid and ventricular spaces, cerebral tissue, and hyperintense areas on T2-weighted images were calculated. In order to reduce interindividual variability caused by differences in intracranial size, each absolute measurement was normalized to the relative size of the intracranial volume. In addition, we calculated the ratio between the areas of the corpus callosum (CC) and supratentorial brain at the same level on the T1-weighted image midsagittal plane. The MRI data were correlated with the deterioration of cognitive functions. Patients with VD showed significantly lower cerebral tissue volume and CC area, and higher ventricular space volume than normal subjects. Furthermore, the total volume of the T2 signal alterations was higher in VD patients than in normal subjects. In VD patients, this volume was found to be proportional to the increase in the volume of the ventricular space. On the other hand, no correlation was found between the volume of the T2 signal alterations and the area of the CC. The degree of global cognitive dysfunction and the score of each neuropsychological test did not show any correlation with the MRI data. Our results suggest that ventricular enlargement in VD patients is correlated with the increase in volume of the T2 signal abnormalities, but that the degree of global cognitive dysfunction is not influenced by the volume of these T2 signal abnormalities. Furthermore, the CC atrophy does not influence the score of any neuropsychological test or the degree of global cognitive dysfunction.

Imaging of a 29-year-old man with seizures showed a frontal lobe mass with curvilinear narrow calcifications, cystic components and multiple flow-voids. An AVM was considered. A DSA confirmed the hypervascular nature of the lesion. It was resected and microscopic examination showed an anaplastic oligodendroglioma remarkable for a diffuse and hypertrophic vasculature with areas of frank vascular proliferation. The marked vascularity seen on the MRI, the gyriform calcifications and the cystic degeneration are all features which can be encountered in an AVM. This case illustrates that highly vascular malignant gliomas can simulate vascular lesions by radiology and may require an angiogram for diagnosis.

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.

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.

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.

The aim of this study was to evaluate the relationships of morphological and CBF patterns with both the severity and the evolution of the motor deficit in the late phase of stroke and, in particular, to identify morphological and/or functional brain alterations associated with a persistent severe motor deficit or a poor, delayed motor recovery. We analysed CT/MRI and single photon emission tomography (SPET) findings from 37 patients studied in the chronic phase of stroke (mean duration +/- SD = 3.6 +/- 1.6 months), whom we were able to follow clinically for a period of 3 months. The eventual degree of motor recovery correlated significantly (negatively) with the time since stroke at entry, but not with the severity of neurological impairment at entry. The volume, side and location (cortical or subcortical) of the infarct did not correlate with either the severity or the evolution of the motor deficit. Patients with a CT/MRI lesion of the parietal lobe (n = 8) showed a more severe motor deficit than those with other cortical locations. The severity of the motor deficit correlated significantly (negatively) with CBF values in the supplementary motor area (SMA) and parietal areas of the damaged hemisphere, and in the contralateral undamaged primary motor cortex. The degree of motor improvement correlated significantly (positively) with CBF values in the contralateral undamaged thalamus, lentiform and caudate nuclei, and premotor cortex. In the late phase of stroke, the severity of the motor deficit may be positively associated with the functional impairment of associative parietal and frontal areas of the damaged hemisphere. The functional impairment of the basal ganglia-frontal network in the undamaged hemisphere seems to be related to a poor, delayed motor recovery.

Nel presente lavoro viene riportato lo studio clinico e neuroradiologico di un caso di neurinoma primitivo del nervo facciale, affezione relativamente rara. L'insieme dei dati neuroradiologici (RM, TC e TC ad alta risoluzione) ha permesso una precisa diagnosi con una ottimale valutazione dell'estensione del tumore e dei rapporti con le strutture contigue, soprattutto con la catena ossiculare, consentendo un corretto approccio chirurgico e la radicale exeresi. I neurinomi endocranici rappresentano l'8% dei tumori cerebrali ed originano dalle cellule di Schwann dei nn cranici nel loro decorso prima dell'emergenza dal neurocrania. Nell '80% dei casi originano dalla componente vestibolare dell'VIII. Sono abbastanza rari i neurinomi che originano dagli altri nervi cranici e tra questi in particolare quelli del VII che possono localizzarsi lungo tutto il decorso del nervo; più spesso sono o extracranici o all'interno dell'osso temporale. Quelli a localizzazione intracranica possono originare in sede intrapetrosa od originare da cellule embrionali del ganglio genicolato ed estendersi in fossa cranica media. Nel nostro lavoro viene descritto un caso di neurinoma del facciale con localizzazione intrapetrosa a partenza dalle strutture del ganglia genicolato ed estensione nella fossa cranica media. Si sottolinea l'importanza delle metodiche d'immagini utilizzate, RM e TC, che hanno permesso di formulare una precisa diagnosi di natura e di estensione del tumore; di particolare utilità la TC ad alta risoluzione che ha documentato l'invasione della cassa timpanica da parte della neoplasia permettendone la completa asportazione.

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.

Motor recovery is remarkable when the brain is damaged early in life. We describe a case of early damage to the right hemisphere with remarkable reorganization and plastic functional changes, studied by computed neuroimaging. A 31-year-old man had a left-sided hemiplegia at the age of 12, followed by good motor recovery despite a large right cortical-subcortical lesion. Single-photon emission computed tomography with motor activation study showed cerebral blood flow increase in the left premotor and sensorimotor cortices irrespective of the hand he was moving, without flow changes in the right hemisphere. A remarkable reorganization and plastic brain functional changes occurred in a patient after early diffuse damage of the right hemisphere. The study points to a potential role of ipsilateral cortical efferent pathways in subserving hand movements after early cerebral damage.

Viene riportata una revisione della letteratura nella diagnostica dei tumori del glomo timpanico e si espone un caso giunto alla osservazione personale. I dati emersi dalla nostra esperienza sottolineano l'utilità della RM anche nei casi in cui ci si trovi di fronte a tumori glomici timpanici puri. Viene in particolare evidenziato come l'aspetto RM di tale lesione consenta di differenziarla da un concomitante tessuto flogistico sia sulla base della diversa intensità di segnale nelle sequenze T2 pesate che del diverso potenziamento dopo mdc.

We applied the technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) split-dose method in order to evaluate the feasibility of assessing cerebral blood flow (CBF) changes with single photon emission tomography (SPET) during a motor activation task. Eleven normal subjects were studied using the Tomomatic 564 (Medimatic, DK). Five subjects were studied twice at rest and 6 subjects at rest and during a motor task performance (finger opposition movements). A total of 28 mCi of 99mTc-HMPAO was injected in 2 doses with a 1:3 ratio. The first scan was obtained after injection of 7 mCi at rest in all subjects. The second scan was obtained a few minutes later, after injection of the remaining dose (21 mCi), under similar resting conditions or during a motor task performance. The mean brain uptake was proportional to the amount of tracer injected and to the acquisition time for both the first scan (5263±1266 counts × mCi × min) and the second (5034.4±966 counts × mCi × min). The grey/white matter ratio was 1.67±0.019 and 1.67±0.097 for the two scans, respectively. A three-way analysis of variance (ANOVA) for repeated measure showed no significant effects of side, slice and region of interest (ROI) on the CBF in the 5 subjects studied twice at rest, and the mean regional CBF change was −0.2%±5%. In the 6 subjects studied at rest and during motor activation, the image subtraction analysis showed a significant CBF increase in the primary motor cortex contralateral to the stimulated side (15%±7%, n=6) and medially in the supplementary motor area (22%±12%, n=4). Our results indicate that the split-dose method allows the detection of a local CBF response to motor activation using 99mTc-HMPAO in a single imaging session.

Abbiamo valutato la sede e l'estensione del sanguinamento subaracnoideo con la TC, l'esordio ed il follow-up clinico in 23 pazienti affetti da ESA con angiografia negativa. L'esordio clinico dell'ESA con angiografia negativa è meno drammatico che nei casi con documentazione di aneurisma cerebrale, più bassa la percentuale di vasospasmo ed ischemia cerebrale tardiva, migliore la prognosi in relazione a nuovi sanguinamenti. I nostri dati confermano come l'ESA con angiografia negativa abbia un andamento più favorevole rispetto all'ESA sostenuta da patologia aneurismatica. Il migliore andamento clinico sembra indipendente dalla localizzazione del sangue nella fase acuta della sintomatologia.

Gelastic (laughing) epilepsy, relatively uncommon, is usually associated with hypothalamic hamartomas, pituitary tumors, astrocytomas of the mammillary bodies, and dysraphic conditions. Cases of unknown etiology are rare. In three of the four cases reported here, the diagnoses were hamartoma of the tuber cinereum; lobar holoprosencephaly; and lissencephaly type I, grade 2. In the fourth, radiographic investigation gave a normal result; a genetic etiology was suggested because of bilateral familial idiopathic epilepsy. In all patients, EEGs showed both focal spikes and generalized spike-and-wave discharges. The primary underlying neurophysiologic disorder may be provoked by the diffuse hyperexcitability of the cortex and subsequent firing of the thalamocortical networks with which the cortical brain is reciprocally interlinked.

Background: Unenhanced computed tomography (CT) is the imaging technique used in acute stroke. In some cases it is unable to detect damage even 24–48 h after symptom onset. The aim of our work was to evaluate the diagnostic value of diffusion-weighted imaging (DWI) in the post-acute phase of cerebral ischemia in patients in whom CT did not yield a definitive diagnosis. Methods: We retrospectively evaluated DWI findings in 214 patients, out of a series of 1,680 patients admitted to our hospital following the acute onset of focal neurological symptoms, in whom non-contrast CT, performed within 30 h of symptom onset, was normal (123), incongruous, i.e. a marked hypodensity indicative of an old infarct or a slight hypodensity not consistent with the clinical findings (66), or leukoaraiotic, i.e. diffuse chronic hypodensities in the periventricular white matter (25). Results: DWI showed signs of recent brain ischemia in 125/214 (58%) patients: 64/123 (52%) with a normal CT, 41/66 (62%) with an incongruous CT, and 20/25 (80%) with leukoaraiosis (p = 0.027). Multiple lesions were detected in 16/125 (16%) patients, while single lesions were ≤2 cm in 83/109 (76%) cases. DWI showed signs of ischemia in 22/91 (24%) patients with TIA and in 103/123 (84%) patients with stroke (p = 0.0001). Conclusion: In a quite high proportion of patients with recent symptoms of transient ischemic attack/ischemic stroke and a repeat non-diagnostic CT, DWI may help in the diagnosis of ischemic stroke and in shedding light on the underlying pathogenic mechanism.

Functional magnetic resonance imaging (fMRI) research has shown that brain arteriovenous malformations (AVMs) lead to reorganization of cortical motor areas. Since it is known that blood oxygenation level-dependent signal in fMRI may be influenced by the hemodynamic perturbation associated with the presence of the AVM, in the present study, a combined exploration with fMRI and transcranial magnetic stimulation was performed in a patient with a right rolandic AVM in order to explore the relationship between neuronal and hemodynamic activity. The combined protocol of investigation adopted in this study was able to provide significant information regarding neuronal activity of the different cortical areas that partake to post-lesional reorganization.

Summary Purpose: We characterized a family with autosomal dominant lateral temporal epilepsy (ADLTE) whose proband presented uncommon electroclinical findings such as drug-resistant seizures and recurrent episodes of status epilepticus with dysphasic features. Methods: The electroclinical characteristics and LGI1 genotype were defined in the family. In the proband, the ictal pattern was documented during video-EEG monitoring and epileptic activity was mapped by EEG/fMRI. Results: The affected members who were studied had drug-resistant seizures. In the proband, seizures with predominant dysphasic features often occurred as partial status epilepticus. The video-EEG-documented ictal activity and fMRI activation clearly indicated the elective involvement of the left posterior lateral temporal cortex. Sequencing of LGI1 exons revealed a heterozygous c.367G>A mutation in exon 4, resulting in a Glu123Lys substitution in the protein sequence. Conclusions: The uncommon clinical pattern (high seizure frequency, drug-resistance) highlights the variability of the ADLTE phenotype and extends our knowledge of the clinical spectrum associated with LGI1 mutations.

Gli autori riferiscono la loro esperienza su 8 pazienti affetti da rinofibroma osservati nel periodo 1988–91. Tutti i pazienti sono stati esaminati con TC, RM ed angiografia. È stata inoltre eseguita una seduta di embolizzazione preoperatoria. I reperti operatori hanno confermato la validità della TC e della RM nel precisare l'estensione della lesione. Le modificazioni della massa tumorale indotte dalla embolizzazione hanno permesso una rimozione radicale con scarsa perdita di sangue.

La RM diretta consente di documentare con chiarezza sede, numero e dimensioni delle placche di demielinizzazione e valutare tali aspetti in esami seriati nel tempo. È possibile in tal modo documentare la comparsa di nuove placche o l'aumento di volume di placche preesistenti, indici di progressione della malattia. Durante la fase acuta (fase di attività) che Jura circa 2 mesi, è presente a livello della placca una alterazione della barriera emato - encefalica, apprezzabile alla RM, dopo somministrazione endovenosa di mezzo di contrasto paramagnetico, sotto forma di impregnazione: questa è stata osservato, come prevedibile, nelle placche di nuova formazione ed in quelle che aumentavano di volume; è stata però anche osservata in placche di demielinizzazione che, restando stabili nel tempo per morfologia e dimensioni all'esame di RM senza mezzo di contrasto, erano state considerate come croniche. L'utilizzo della Gadolinio-DTPA in RM fornisce quindi informazioni sullo stato della barriera emato - encefalica, espressione di attività di placca e quindi di attività di malattia, informazioni di importanza notevole ai fini di un corretto approccio prognostico e terapeutico.

Gli autori hanno cercato di definire, alla luce delle attuali esperienze, l'utilità del contrasto paramagnetico (Gadolinio - DTPA) nello studio diagnostico, tramite risonanza magnetica, della patologia cerebrovascolare ischemica. Vengono analizzati in breve la fisiopatologia dello sviluppo del danno ischemico parenchimale e il meccanismo d'azione dell'impregnazione dell'area infartuata, dopo iniezione di contrasto per vena, nei vari stadi del suo sviluppo. L'assenza di danni radiobiologici, la maggiore sensibilità rispetto alla TC, la possibilità di indagine multiplanare rendono la RM con contrasto paramagnetico, metodica particolarmente utile nel diagnosticare piccoli infarti situati in territori vascolari terminali profondi (talamo, nucleo della base, tronco dell'encefalo) e corticali molto superficiali, oltre che nel doocumentare eventuali minime alterazioni di barriera anche in una fase molto precoce del loro sviluppo. Controlli seriati, possibili per l'innocuità della metodica RM, potrebbero essere effettuati nello stesso paziente al fine di valutare l'esatta evoluzione temporale del danno di barriera nell'area infartuata; ciò permetterebbe di monitorare, già in una fase molto acuta di sviluppo del danno parenchimale, interventi terapeutici mirati o farmacologici (anticoagulanti) o chirurgici (disobliterazione vasale) senza incorrere nel temuto infarcimento emorragico della lesione ischemica.

To prospectively evaluate use of diffusion-weighted (DW) magnetic resonance (MR) images and apparent diffusion coefficient (ADC) maps for determination of the consistency of macroadenomas.The study protocol was approved by the institutional ethics committee, and informed consent was obtained from all patients. Twenty-two patients with pituitary macroadenoma (10 men, 12 women; mean age, 54 years +/- 17.09 [standard deviation]; range, 21-75 years) were examined. All patients underwent MR examination, which included T1-weighted spin-echo and T2-weighted turbo spin-echo DW imaging with ADC mapping and contrast material-enhanced T1-weighted spin-echo imaging. Regions of interest (ROIs) were drawn in the macroadenomas and in normal white matter on DW images, ADC maps, and conventional MR images. Consistency of macroadenomas was evaluated at surgery and was classified as soft, intermediate, or hard. Histologic examination was performed on surgical specimens of macroadenomas. Mean ADC values, signal intensity (SI) ratios of tumor to white matter within ROIs on conventional and DW MR images, and degree of enhancement were compared with tumor consistency and with percentage of collagen content at histologic examination by using analysis of variance for linear trend.The mean value of ADC in the soft group was (0.663 +/- 0.109) x 10(-3) mm(2)/sec; in the intermediate group, (0.842 +/- 0.081) x 10(-3) mm(2)/sec; and in the hard group, (1.363 +/- 0.259) x 10(-3) mm(2)/sec. Statistical analysis revealed a significant correlation between tumor consistency and ADC values, DW image SI ratios, T2-weighted image SI ratios, and percentage of collagen content (P.001, analysis of variance). No other statistically significant correlations were found.Findings in this study suggest that DW MR images with ADC maps can provide information about the consistency of macroadenomas.

Summary: Purpose: Electroencephalography/functional magnetic resonance imaging (EEG/fMRI) has been proposed recently as a tool to study electrophysiological activity and, consequently, detect brain regions activated during epileptiform EEG abnormalities. The purpose of the study was to review our two-year experience with studying ictal and interictal activities in patients with epilepsy. Methods: Using EEG/fMRI, we studied hemodynamic changes associated with ictal and interictal EEG abnormalities in 43 patients with partial (31 cases) or generalized (12 cases) epilepsy. Using two different paradigms (block design and event-related design), we studied several forms of EEG activity consisting of (i) interictal abnormalities constantly elicitable by specific stimulation (8 cases); (ii) focal and generalized interictal activity, such as focal spikes or typical and atypical generalized spike-and-wave discharges (18 cases); and (iii) focal and generalized ictal electro-clinical activity, such as tonic seizures or pseudo-absences in frontal lobe epilepsy, typical absences in idiopathic generalized epilepsy, complex partial seizures in temporal lobe epilepsy, and perisylvian seizures in special syndromes (17 patients). Results: EEG/fMRI revealed clear hemodynamic changes related to EEG abnormalities in 21 patients. In 18 of these patients, the changes were highly concordant with electro-clinical findings. In the remaining 22 patients, fMRI analysis data failed to show activation or deactivation clusters, probably owing either to lack or inadequate amount of temporal distribution of abnormal EEG activity, or to intrinsic methodological problems. Conclusions: By defining the electro-clinical and hemodynamic correlates of EEG activity, fMRI may shed light on the neurophysiological mechanisms underlying epileptic phenomena. However, as several methodological issues have yet to be addressed, further studies are warranted to assess the reliability and usefulness of EEG/fMRI in clinical practice.

Leukoaraiosis (LA) is the widely accepted definition for the changes in the white matter of the brain frequently detected in the elderly by neuroimaging techniques. LA has a vascular pathogenesis and is a definite contributory factor for stroke, cognitive decline and dementia. Theoretically, though not yet in practice, if these lesions are detected at an early stage treatment can be instituted promptly, thereby preventing a catastrophic event later. Here we concisely review the relevant literature and stress the imaging of LA and its clinical significance.

Recently EEG/functional magnetic resonance imaging (f MRI) has been proposed in epilepsy research to study and map electrophysiological activity. It can detect regions in the brain activated during interictal or ictal EEG abnormalities and thus contribute to a clearer understanding of neurophysiologic mechanisms underlying epileptic phenomena (1‐3). However, f MRI studies are limited by a number of factors: some are related to the technique itself (nonstandardized technical approach, heterogeneous procedures used in the experimental paradigms, image processing and statistical analysis, and varying sensitivity of the instrument), whereas others are related to the seizures (unpredictable occurrence, technical problems, and artifact on images in case of motor activity). It may, consequently, be difficult to verify the reproducibility of results over time, as is suggested by the lack of studies focusing on this aspect.

3,4-diaminopyridine (3,4-DAP), a potassium (K+) channel blocker, improves fatigue and motor function in multiple sclerosis (MS). Although it was thought to do so by restoring conduction to demyelinated axons, recent experimental data show that aminopyridines administered at clinical doses potentiate synaptic transmission.To investigate motor cerebral activity with fMRI and transcranial magnetic stimulation (TMS) after a single oral dose of 3,4-DAP in patients with MS.Twelve right-handed women (mean +/- SD age 40.9 +/- 9.3 years) underwent fMRI on two separate occasions (under 3,4-DAP and under placebo) during a simple motor task with the right hand. FMRI data were analyzed with SPM99. After fMRI, patients underwent single-pulse TMS to test motor threshold, amplitude, and latency of motor evoked potentials, central conduction time, and the cortical silent period; paired-pulse TMS to investigate intracortical inhibition (ICI) and intracortical facilitation (ICF); and quantitative electromyography during maximal voluntary contraction.FMRI motor-evoked brain activation was greater under 3,4-DAP than under placebo in the ipsilateral sensorimotor cortex and supplementary motor area (p0.05). 3,4-DAP decreased ICI and increased ICF; central motor conduction time and muscular fatigability did not change.3,4-DAP may modulate brain motor activity in patients with MS, probably by enhancing excitatory synaptic transmission.