Mc Michelassi

Assessment of midbrain atrophy in patients with progressive supranuclear palsy with routine magnetic resonance imaging

Objectives –  To assess midbrain atrophy through morphometric (linear, surface and volumetric) measurements in patients with clinically diagnosed progressive supranuclear palsy (PSP) and to establish the most accurate measure to be implemented in routine magnetic resonance (MR) protocol in distinguishing PSP from healthy subjects and MSA‐p (multiple system atrophy, parkinsonian form) patients.

Contrast-enhanced three-dimensional MR angiography of neck vessels: does dephasing effect alter diagnostic accuracy?

Abstract. The aim of this study was to evaluate diagnostic accuracy of contrast-enhanced MRA (CEMRA) compared with digital subtraction angiography (DSA) in studying neck vessels of 48 patients. In three groups of patients, we used three MRA protocols differing for voxel size to assess if intravoxel dephasing effects could modify accuracy of CEMRA. Accuracy and correlation with DSA results were calculated in all patients and separately in the three groups. A qualitative analysis of the likeness between morphology of the stenosis in CEMRA and DSA images was also assessed. In all patients accuracy and agreement with DSA were 96% and k=0.85 in subclavian arteries, 96% and k=0.84 in vertebral artery, 97% and k=0.88 in common carotid arteries, and 94% and k=0.86 in internal carotid arteries. In the three groups accuracy and agreement with DSA did not show any significant difference. Qualitative analysis of CEMRA and DSA images revealed a better agreement in depicting the morphology of stenosis using a smaller voxel size. The CEMRA represents a powerful tool for the non-invasive evaluation of neck vessels. Overestimation trend of CEMRA is confirmed and the reduction of voxel size, decreasing the dephasing intravoxel effect, allows to have a better overlapping of stenosis morphology on CEMRA compared with DSA, but it does not yield diagnostic gain in the stenosis grading.

Cyclosporine-related posterior reversible encephalopathy syndrome (PRES) in non-transplant patient : a case report and literature review

A 53-year-old Caucasian female was referred because of acute speech difficulties and mental confusion. Six months prior to the referral she was treated by acetylsalicylic acid (325 mg/day) and methylprednisolone (4 mg/day), associated with cyclosporine A (CsA) (175 mg/ day) for psoriatic arthritis. A pure motor aphasia with recovery in 24 h was present, without other neurological signs. Blood investigation and blood pressure were normal. A cranial computed tomography (CT) depicted extensive areas of low attenuation involving the white matter (WM) of the temporo-parietal-occipital lobes. Cerebrospinal fluid examination and Doppler of the epiaortic vessels were normal. Magnetic resonance imaging showed a diffuse area, of high signal intensity (SI) on FLAIR and T2-weighted images and of low SI on T1-weighted ones, in the temporo-parieto-occipital WM including the subcortical U fibers. The alteration had major extension on the left hemisphere, mainly the fronto-parietal WM and temporo-occipital cortical layer, causing a partial sulcal effacement (Fig. 1a,b). No pathological contrastenhancement was appreciable. Diffusion weighted (DW) sequences showed isointensity of the lesions indicative of vasogenic edema (Fig. 1c). Clinical and MR findings suggested a toxic leukoencephalopathy. The patient gradually replaced cyclosporine with salazopyrine (2 g/day). Three months later, an MR examination showed a clear-cut reduction of the alteration (Fig. 1d–e), confirming the

Atypical Posterior Reversible Encephalopathy Syndrome in Puerperium

A 37-year-old woman with no significant past medical history presented on the 4th day of puerperium with sudden headache and severe bilateral visual disturbance (blurring and teichopsia) followed by isolated generalized tonic-clonic seizure. No other impairment was observed at neurological examination. Arterial blood pressure was consistently elevated (180/110 mm Hg). Blood and urine routine assays were normal, and no proteinuria was detected during both the pregnancy and puerperium. Cranial CT scan was unremarkable, whereas MRI FLAIR and FSET 2 sequences revealed scattered areas of increased signal in subcortical occipital and posterior parietal white matter, and more confluent areas of signal hyperintensity in the grey matter of the striatum, in the external and internal capsule bilaterally and in the upper brainstem ( fig. 1 a, b). Diffusion-weighted images (DWI) revealed signal isointensity or slight hyperintensity of the affected areas with an increase in the apparent diffusion coefficient (ADC) indicating vasogenic edema. MR venography was also performed to evaluate the deep venous system, and resulted normal. The patient was treated with labetalol 20 mg i.v. for 2 min followed by 40 mg i.v. at 10-min intervals until normalization of Dear Sir, Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiological entity characterized by headache, visual loss and epileptic seizures in a severe arterial hypertension setting due to hypertension-inducing diseases, such as renal diseases or eclampsia [1, 2] . Moreover, PRES can also be caused by hypertension-inducing treatments (i.e. erythropoietin, blood transfusion or immunosuppressants) [1] . Brain MRI typically documents vasogenic edema involving the occipitoparietal regions [3] as a result of loss of cerebral autoregulation related to hypertensive endothelial dysfunction and disruption of blood-brain barrier with increased permeability [4] . If PRES is diagnosed at the right time, both clinical signs and neuroradiological pattern are frequently reversible, whereas delayed diagnosis and treatment can lead to ischemic or hemorrhagic lesions with permanent neurological damage [4] . Edema can rarely involve the brainstem or the hemispheric deep structures. In this case, the resulting syndrome is called atypical PRES [5] . Misdiagnosis is a frequent event and involves vertebrobasilar ischemia, cerebral venous thrombosis and metabolic diseases. Here, we report two unusual cases of atypical PRES during puerperium with good outcome. Received: January 31, 2007 Accepted: May 22, 2007 Published online: January 29, 2008

Redistribuzione del flusso ematico misurato con Angio-RM 2D Fast-PC nella stenosi della carotide interna

La causa più frequente di ischemia cerebrale è rappresentata dalla tromboembolia dovuta a placche aterosclerotiche dei vasi cerbroafferenti. La patogenesi emodinamica nell’ischemia cerebrale gioca solo un ruolo marginale. Al fine di programmare una tromboendoarterectomia (TEA), un corretto inquadramento diagnostico con tecniche non invasive, come l’ecocolor Doppler e la risonanza magnetica tridimensionale con bolo di contrasto (CEMRA) sembra incrementare il beneficio del trattamento chirurgico. La possibilità di misurare quantitativamente il flusso e la velocità all’interno di un vaso utilizzando tecniche bidimensionali contrasto di fase triggerate permette di ottenere utili informazioni sull’impatto emodinamico di una stenosi carotidea. Nelle stenosi aterosclerotiche dei vasi del collo, le tecniche contrasto di fase, fornendo un dato emodinamico, consentono una valutazione quantitativa del grado di compromissione del flusso ematico all’interno del vaso in studio e possono essere utili nella valutazione della progressione o della stabilità di malattia. Diverse tecniche di imaging permettono la valutazione del flusso ematico totale, tra queste però solo l’eco-colo Doppler e la risonanza magnetica contrasto di fase forniscono informazioni quantitative sul flusso ematico in ogni singolo vaso. Lo scopo di questo studio è quello di valutare il volume ematico totale afferente all’encefalo con tecnica fast PC e la sua ridistribuzione nei pazienti con stenosi dell’arteria carotide interna (ICA). Materiale e metodi