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BACKGROUND: Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI)-based methodology widely used for the evaluation of microstructural integrity of the central nervous system (CNS), particularly of brain white matter fibers and bundles. METHODS: The most common parameters evaluated in a DTI study are the fractional anisotropy (FA) and mean diffusivity (MD). Combining FA and MD analyses is commonly used in the evaluation of various types of brain pathologies, such as brain tumors, where a combined analysis allows an accurate tumor characterization. RESULTS: Recent studies have shown that FA and MD could be of value in non-oncologic spinal pathology. In this regard, it has been demonstrated that DTI can provide new insights into the diagnosis and prognosis of cervical spondylotic myelopathy and cervical spinal cord injury. CONCLUSIONS: Further studies are needed to assess the role of DTI in such a new clinical scenario.
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OBJECTIVE: The aim of this study is to investigate the role of a computed tomography angiography (CTA)-based approach in patients undergoing mechanical thrombectomy for vertebrobasilar stroke treatment. METHODS: A CTA and digital subtraction angiography (DSA) retrospective analysis of patients with acute vertebrobasilar stroke treated with thrombectomy was performed. A modified Rankin Scale score of 3 or lower at 3 months was considered as favorable outcome. The posterior circulation ASPECTS (pc-ASPECTS) was evaluated on CTA and vertebrobasilar segments involved in the occlusion were assessed using a 6-point posterior circulation computed tomography angiography (pc-CTA) vascular score aimed at evaluating the posterior circulation vascular pattern including collaterals. The primary end point was the correlation between pc-CTA and outcome; secondary end points included the concordance between CTA-DSA images and the correlation between pc-ASPECTS and outcome. RESULTS: Fifteen patients with vertebrobasilar stroke were retrospectively analyzed. All patients in coma showed a bad outcome (P = .01) and all patients with an alert state showed a good outcome (P = .004). An excellent interobserver agreement for pc-CTA (P = .001) was observed with poor interobserver agreement for pc-ASPECTS (P = .21). No significant correlations between pc-ASPECTS and clinical outcome were observed. Patients with good outcome had a lower pc-CTA (P = .02). The patency of the distal third of the basilar artery and both posterior cerebral arteries was related with good outcome. CONCLUSION: The pc-CTA seems to have prognostic value in patients with vertebrobasilar stroke undergoing mechanical thrombectomy. It may be used as an additional prognostic triage technique in this subgroup of stroke patients.
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Infarto Encefálico/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Trombectomia/métodos , Adulto , Idoso , Angiografia Digital , Infarto Encefálico/cirurgia , Angiografia Cerebral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Acidente Vascular Cerebral/cirurgia , Resultado do TratamentoRESUMO
INTRODUCTION: Kennedy's disease (KD) is a progressive degenerative disorder affecting lower motor neurons. We investigated the correlation between disease severity and whole brain white matter microstructure, including upper motor neuron tracts, by using diffusion-tensor imaging (DTI) in eight patients with KD in whom disease severity was evaluated using the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS). METHODS: From DTI acquisitions we obtained maps of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (L1) and radial diffusivities (L2, L3). We then employed tract-based spatial statistics (TBSS) to investigate within-patient correlations of DTI invariants with ALSFRS and disease duration (DD). RESULTS: We found a significant correlation between low ALSFRS and 1) low FA values in association commissural and projection fibers, and 2) high L3 values in commissural tracts and fronto-parietal white matter. Additionally, we found a significant association between longer DD and 1) low FA in the genu and body of corpus callosum, association fibers and midbrain and 2) high L1 in projection and association tracts. CONCLUSIONS: The associations between clinical variables and white matter microstructural changes in areas thought to be spared by the disease process support the hypothesis of a multisystem involvement in the complex pathogenic mechanisms responsible for the clinical disability of these patients.
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Encéfalo/patologia , Atrofia Bulboespinal Ligada ao X/patologia , Imagem de Tensor de Difusão/métodos , Fibras Nervosas Mielinizadas/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: The efficacy of thrombolytic treatment with recombinant tissue plasminogen activator (rt-PA) within 3 h from stroke onset has been extensively supported by randomised placebo-controlled multicentre trials. In our single-centre study, we investigated the efficacy of intravenous (IV) administration of rt-PA within 4.5 h of stroke onset, in terms of clinical and radiological outcome, using a 3T magnetic resonance (MR) scanner in a cohort of patients similar to that of multicentre clinical trials. MATERIALS AND METHODS: Consecutive patients treated with IV rt-PA were compared with an historical cohort of untreated patients (controls). Inclusion criteria were: (1) infarction of the middle cerebral artery territory, (2) eligibility for IV rt-PA treatment, and (3) 3T perfusion- and diffusion-weighted MR imaging and MR angiography performed within 4.5 h and repeated after 5-7 days. Stroke severity was assessed with the National Institutes of Health Stroke Scale (NIHSS). Growth of the DWI lesion, saved hypoperfused tissue, and clinical outcome was assessed and compared in treated patients and controls. RESULTS: Forty-three patients treated with rt-PA and 69 controls were eligible for the analysis. Treated patients showed higher percentages of saved hypoperfused tissue (75 vs. 40 %; p = 0.009), vessel recanalisation (65 vs. 27.5%; p = 0.003), and haemorrhagic transformation (21 vs. 7%; p = 0.004), without any clinically significant haemorrhages. Furthermore, treated patients had a significant improvement of NIHSS at 24 h (p < 0.001), at discharge (p ≤ 0.001), and at the 3-month clinical evaluation (p < 0.001), while similar rates of both treated patients and controls achieved a 3-month modified Rankin scale ≤ 2 (62 and 65%; p = 0.7). CONCLUSION: Treatment with IV rt-PA within 4.5 h of stroke onset preserves a significant amount of brain tissue from final infarction, and increases the possibility of early and late clinical improvement.
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Imagem de Difusão por Ressonância Magnética , Fibrinolíticos/uso terapêutico , Angiografia por Ressonância Magnética , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Administração Intravenosa , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Terapia Trombolítica/métodos , Fatores de Tempo , Ativador de Plasminogênio Tecidual/administração & dosagem , Resultado do TratamentoRESUMO
The aim of this study was to identify potential diagnostic markers of Hereditary Spastic Paraplegia (HSP). We investigated the white matter features of spastic gait (SPG)11- and SPG4-linked HSP, using diffusion tensor imaging performed with a 3-Tesla (3T) scanner. We examined four patients with SPG11 mutations, three with SPG4 mutations, and 26 healthy controls. We obtained maps of fractional anisotropy (FA) and mean diffusivity (MD), which we analyzed through both region of interest -based approach and tract-based spatial statistics (TBSS). Compared with healthy controls, SPG11 patients presented increased MD and decreased FA in the semioval centers, frontal and peritrigonal white matter, posterior limb of the internal capsule, and throughout the corpus callosum. Similar alterations were seen in the SPG4 patients at the levels of the semioval centers, the posterior limb of the internal capsule, the left cerebral pedicle, the genu and trunk of the corpus callosum, and the peritrigonal white matter on the left. No MD or FA alterations were observed in the cerebellar white matter. In a direct comparison, white matter alterations were more pronounced and widespread in HSP-SPG11 than in HSP-SPG4 patients. Joint TBSS analysis of all three groups confirmed significant widespread alterations of FA and MD values in the supratentorial white matter. This noninvasive study documented the presence of altered diffusivity in white matter in both forms of HSP, which could represent an important diagnostic marker of HSP. The association of reduced FA and increased MD in this patient population supports the interpretation of HPG as a neurodegenerative disorder.
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Adenosina Trifosfatases/genética , Imagem de Tensor de Difusão , Fibras Nervosas Mielinizadas/patologia , Proteínas/genética , Adulto , Anisotropia , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Mutação , Neuroimagem , Paraplegia/diagnóstico , Paraplegia/genética , Paraplegia/patologia , Paraplegia Espástica Hereditária/diagnóstico , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/patologia , Espastina , Adulto JovemRESUMO
PURPOSE: To investigate the relationship between chronic cerebrospinal venous insufficiency (CCSVI) and cerebral hemodynamic parameters and to disclose any possible involvement in the pathophysiology of multiple sclerosis (MS). MATERIALS AND METHODS: The study was approved by the institutional review board, and written informed consent was obtained from all participants. The diagnosis of CCSVI was assigned by using specific color Doppler ultrasonographic criteria. Cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time were assessed with dynamic susceptibility contrast material-enhanced magnetic resonance imaging in normal-appearing white matter (NAWM) in 39 patients with MS. Of these, 25 had CCSVI and 14 did not. Twenty-six healthy control subjects were also evaluated, and of these, 14 had CCSVI and 12 did not. Two-way analysis of variance testing was used for statistical analysis, with Bonferroni correction for multiple comparisons. Correlation analysis was performed by calculating Spearman coefficients. RESULTS: Individuals with CCSVI showed cerebral hemodynamic anomalies, such as decreased CBF and CBV, as compared with individuals without CCSVI, without any delay in mean transit time. No significant interaction between MS and CCSVI was found for any hemodynamic parameters. Furthermore, no correlations were found between CBV and CBF values in NAWM or for severity of disability in patients with MS. The MS group showed prolonged mean transit time in the periventricular NAWM, as compared with the control group, and positive correlation was found between mean transit time values and disability scales in patients with MS. CONCLUSION: The data support a role of CCSVI in cerebral hemodynamic changes, such as a decrease of CBV and CBF, regardless of the presence of MS. CCSVI had no effect on neurologic function and disability progression in patients with MS.
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Circulação Cerebrovascular , Hemodinâmica/fisiologia , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/fisiopatologia , Insuficiência Venosa/fisiopatologia , Adulto , Análise de Variância , Velocidade do Fluxo Sanguíneo , Volume Sanguíneo , Estudos de Casos e Controles , Meios de Contraste , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Ultrassonografia Doppler em CoresRESUMO
PURPOSE: To analyze in vivo the diffusion tensor magnetic resonance imaging (DT-MRI) properties of the intraorbital optic nerve at two different levels: Proximal to the optic nerve head (ONH) and distal to the ONH at the level of the orbital apex in glaucoma patients. METHODS: Twenty-four patients with primary open-angle glaucoma were examined. The categorization into early and severe glaucoma was performed by Hodapp's classification. Fifteen healthy individuals served as controls. DT-MRI was performed with a 3T-MR unit. RESULTS: At early stage mean diffusivity (MD) values were higher at the proximal site with respect to the distal site. On the contrary, a decrease in fractional anisotropy (FA) was observed only relative to patient stage, independent of optic nerve site. Moreover, at early disease stage an increase in overall diffusivities, was evident at the proximal site, whereas at the distal site a decrease of the largest diffusivity and an increase in both the intermediate and smallest diffusivities were observed. FA and MD measured at the proximal site, had, respectively, the highest sensitivity and specificity in discriminating between healthy and glaucomatous eyes. CONCLUSIONS: Our study represents the first attempt to evaluate in vivo fiber integrity changes along the optic nerve with DT-MRI. Optic nerve degeneration appears to be a process that affects differently the proximal and the distal segments of the optic nerve. The complementary high sensitivity of FA with the high specificity of MD at the proximal site may provide reliable indexes for the identification of glaucomatous patients at early stages.
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Imagem de Tensor de Difusão/métodos , Glaucoma de Ângulo Aberto/diagnóstico , Nervo Óptico/patologia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Índice de Gravidade de DoençaRESUMO
PURPOSE: This study was designed to evaluate the efficacy of CT-guided injection of anesthetic and corticosteroid for the treatment of pain in patients with piriformis syndrome unresponsive to conservative treatment. METHODS: We enrolled 23 patients with piriformis syndrome, proposing a percutaneous intramuscular injection of methylprednisone-lidocaine. Among them, 13 patients accepted and 10 refused to undergo the procedure; the second group was used as a control group. Clinical evaluation was performed with four maneuvers (Lasègue sign, FAIR test, Beatty and Freiberg maneuver) and a VAS questionnaire before the injection, after 5-7 days, and after 2 months. A telephonic follow-up was conducted to 3, 6, and 12 months. RESULTS: Procedural success was achieved in all patients who were treated without any complications. After 2 months, among 13 treated subjects, 2 of 13 patients showed positivity to FAIR test (hip flexion, adduction, and internal rotation), 2 of 13 were positive to Lasègue sign, and the Beatty maneuver was positive in 1 patient. Patients who underwent conservative treatment were positive respectively in 7 of 10 (p = 0.01), 6 of 10 (p = 0.03), and 6 of 10 (p = 0.01). The VAS score showed a difference between patients treated with percutaneous approach and those managed with conservative therapy at the baseline evaluation (p = 0.04), after 2 months (p = 0.02), and 12 months (p = 0.002). We observed a significant reduction in pain for patients treated percutaneously, who were evaluated with the VAS scale at 5-7 days, 2 months, 3, 6, and 12 months (p < 0.001). CONCLUSIONS: Our findings suggested potential benefit from the percutaneous injection of anesthetics and corticosteroids under CT guidance for the treatment of piriformis syndrome.
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Lidocaína/administração & dosagem , Metilprednisolona/administração & dosagem , Dor/prevenção & controle , Síndrome do Músculo Piriforme/tratamento farmacológico , Adulto , Anestésicos/administração & dosagem , Combinação de Medicamentos , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Humanos , Injeções Intramusculares , Imageamento por Ressonância Magnética , Masculino , Dor/etiologia , Medição da Dor , Síndrome do Músculo Piriforme/complicações , Síndrome do Músculo Piriforme/diagnóstico , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
OBJECTIVES: To prospectively investigate diagnostic value and tolerability of MRI after intra-vaginal gel opacification for diagnosis and preoperative assessment of deeply infiltrating endometriosis. METHODS: Sixty-three women with clinical suspicion of deeply infiltrating endometriosis were previously examined with trans-vaginal ultrasonography and then with MRI pre and post administration of vaginal gel. We evaluated the tolerability of this procedure with a scoring scale from 0 to 3. We also assessed with a score from 1 to 4 the visibility of four regions: Douglas-pouch, utero-sacral-ligaments, posterior-vaginal-fornix and recto-vaginal-septum. All patients underwent laparoscopic surgery after MRI. RESULTS: Five patients considered procedure intolerable. Visibility of utero-sacral-ligaments and posterior-vaginal-fornix showed to be increased with gel (p<0.001). In 57 out of 80 patients the MRI has allowed us to diagnose deeply infiltrating endometriosis. Overall, the percentages of MRI-sensitivity, specificity, positive predictive value and negative predictive value were respectively 67.8%, 95.3%, 89.4 and 83.5% without gel, and 90.8%, 94.6%, 90.8% and 94.6% with gel; trans-vaginal ultrasonography sensitivity, specificity, positive predictive value and negative predictive value were 57.5%, 96.6%, 90.9% and 79.5%. In evaluation of utero-sacral-ligaments trans-vaginal ultrasonography, MRI without gel and with gel sensitivity was respectively 61.9%, 47.6% and 81%; for recto-vaginal-septum these values were 12.5%, 68.7% and 93.7%; for pouch of Douglas 82%, 87% and 97.4%; finally for posterior-vaginal-fornix 27.3%, 36.4% and 81.8%. CONCLUSIONS: MRI with gel opacification of vagina should be recommended for suspicion of deep infiltrating endometriosis, in particular for the added value in evaluation of recto-vaginal septum, utero-sacral ligaments and posterior vaginal fornix.
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Endometriose/patologia , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Técnica de Subtração , Vagina/patologia , Cremes, Espumas e Géis Vaginais , Adulto , Artefatos , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Background. Patients with acute ischemic stroke due to internal carotid artery (ICA) disease are at high risk of early stroke recurrence. A combination of IV thrombolysis and early carotid artery stenting (CAS) may result in more effective secondary stroke prevention. Objective. We tested safety and durability of early CAS following IV thrombolysis in stroke patients with residual stenosis in the symptomatic ICA. Methods. Of consecutive patients treated with IV rtPA, those with residual ICA stenosis ≥70% or <70% with an ulcerated plaque underwent early CAS (>24 hours). The protocol included pre-rtPA MRI and MR angiography, and post-rtPA carotid ultrasound and CT angiography. Stroke severity was assessed by the NIH Stroke Scale (NIHSS). Three- and twelve-month stent patency was assessed by ultrasound. Twelve-month functional outcome was assessed by the modified Rankin Scale (mRS). Results. Of 145 consecutive IV rtPA-treated patients, 6 (4%) underwent early CAS. Median age was 76 (range 67-78) years, median NIHSS at stroke onset was 12 (range 9-16) and 7 (range 7-8) before CAS. Median onset-to-CAS time was 48 (range 30-94) hours. A single self-expandable stent was implanted to cover the entire lesion in all patients. The procedure was uneventful in all patients. After 12 months, all patients had stent patency, and the functional outcome was favourable (mRS ≤ 2) in all but 1 patient experiencing a recurrent stroke for new-onset atrial fibrillation. Conclusion. This small case series of a single centre suggests that early CAS may be considered a safe alternative to CEA after IV rtPA administration in selected patients at high risk of stroke recurrence.