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1.
Neuroradiology ; 66(2): 237-247, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38010403

RESUMO

PURPOSE: Endovascular treatment (EVT) of acute ischemic stroke can be complicated by vessel perforation. We studied the incidence and determinants of vessel perforations. In addition, we studied the association of vessel perforations with functional outcome, and the association between location of perforation on digital subtraction angiography (DSA) and functional outcome, using a large EVT registry. METHODS: We included all patients in the MR CLEAN Registry who underwent EVT. We used DSA to determine whether EVT was complicated by a vessel perforation. We analyzed the association with baseline clinical and interventional parameters using logistic regression models. Functional outcome was measured using the modified Rankin Scale at 90 days. The association between vessel perforation and angiographic imaging features and functional outcome was studied using ordinal logistic regression models adjusted for prognostic parameters. These associations were expressed as adjusted common odds ratios (acOR). RESULTS: Vessel perforation occurred in 74 (2.6%) of 2794 patients who underwent EVT. Female sex (aOR 2.0 (95% CI 1.2-3.2)) and distal occlusion locations (aOR 2.2  (95% CI 1.3-3.5)) were associated with increased risk of vessel perforation. Functional outcome was worse in patients with vessel perforation (acOR 0.38 (95% CI 0.23-0.63)) compared to patients without a vessel perforation. No significant association was found between location of perforation and functional outcome. CONCLUSION: The incidence of vessel perforation during EVT in this cohort was low, but has severe clinical consequences. Female patients and patients treated at distal occlusion locations are at higher risk.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , AVC Isquêmico/etiologia , Isquemia Encefálica/etiologia , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Trombectomia/métodos
2.
Acta Neurochir (Wien) ; 162(1): 79-85, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31802274

RESUMO

OBJECTIVE: This retrospective observational histological study aims to associate the size and type of disc herniation with the degree of macrophage infiltration in disc material retrieved during disc surgery in patients with sciatica. METHODS: Disc tissue of 119 sciatica patients was embedded in paraffin and stained with hematoxylin and CD68. Tissue samples were categorized as mild (0-10/cm2), moderate (10-100/cm2), and considerable (> 100/cm2) macrophage infiltration. All 119 patients received an MRI at baseline, and 108 received a follow-up MRI at 1-year. MRIs were reviewed for the size and type of the disc herniations, and for Modic changes in the vertebral endplates. RESULTS: Baseline characteristics and duration of symptoms before surgery were comparable in all macrophage infiltration groups. The degree of macrophage infiltration was not associated with herniation size at baseline, but significantly associated with reduction of size of the herniated disc at 1-year post surgery. Moreover, the degree of macrophage infiltration was higher in extrusion in comparison with bulging (protrusion) of the disc. Results were comparable in patients with and without Modic changes. CONCLUSION: Macrophage infiltration was positively associated with an extruded type of disc herniation as well as the extent of reduction of the herniated disc during 1-year follow-up in patients with sciatica. This is an indication that the macrophages play an active role in reducing herniated discs. An extruded disc herniation has a larger surface for the macrophages to adhere to, which leads to more size reduction.


Assuntos
Deslocamento do Disco Intervertebral/patologia , Disco Intervertebral/patologia , Vértebras Lombares/patologia , Macrófagos/patologia , Ciática/patologia , Adulto , Feminino , Humanos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Ciática/diagnóstico por imagem , Ciática/cirurgia
3.
Comput Biol Med ; 115: 103516, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31707199

RESUMO

Treatment selection is becoming increasingly more important in acute ischemic stroke patient care. Clinical variables and radiological image biomarkers (old age, pre-stroke mRS, NIHSS, occlusion location, ASPECTS, among others) have an important role in treatment selection and prognosis. Radiological biomarkers require expert annotation and are subject to inter-observer variability. Recently, Deep Learning has been introduced to reproduce these radiological image biomarkers. Instead of reproducing these biomarkers, in this work, we investigated Deep Learning techniques for building models to directly predict good reperfusion after endovascular treatment (EVT) and good functional outcome using CT angiography images. These models do not require image annotation and are fast to compute. We compare the Deep Learning models to Machine Learning models using traditional radiological image biomarkers. We explored Residual Neural Network (ResNet) architectures, adapted them with Structured Receptive Fields (RFNN) and auto-encoders (AE) for network weight initialization. We further included model visualization techniques to provide insight into the network's decision-making process. We applied the methods on the MR CLEAN Registry dataset with 1301 patients. The Deep Learning models outperformed the models using traditional radiological image biomarkers in three out of four cross-validation folds for functional outcome (average AUC of 0.71) and for all folds for reperfusion (average AUC of 0.65). Model visualization showed that the arteries were relevant features for functional outcome prediction. The best results were obtained for the ResNet models with RFNN. Auto-encoder initialization often improved the results. We concluded that, in our dataset, automated image analysis with Deep Learning methods outperforms radiological image biomarkers for stroke outcome prediction and has the potential to improve treatment selection.


Assuntos
Isquemia Encefálica , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Redes Neurais de Computação , Complicações Pós-Operatórias/diagnóstico por imagem , Sistema de Registros , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Acidente Vascular Cerebral/etiologia
4.
AJNR Am J Neuroradiol ; 39(5): 892-898, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29622556

RESUMO

BACKGROUND AND PURPOSE: The absence of opacification on CTA in the extracranial ICA in acute ischemic stroke may be caused by atherosclerotic occlusion, dissection, or pseudo-occlusion. The latter is explained by sluggish or stagnant flow in a patent artery caused by a distal intracranial occlusion. This study aimed to explore the accuracy of CTA for differentiating pseudo-occlusion from true occlusion of the extracranial ICA. MATERIALS AND METHODS: All patients from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) with an apparent ICA occlusion on CTA and available DSA images were included. Two independent observers classified CTA images as atherosclerotic cause (occlusion/high-grade stenosis), dissection, or suspected pseudo-occlusion. Pseudo-occlusion was suspected if CTA showed a gradual contrast decline located above the level of the carotid bulb, especially in the presence of an occluded intracranial ICA bifurcation (T-occlusion). DSA images, classified into the same 3 categories, were used as the criterion standard. RESULTS: In 108 of 476 patients (23%), CTA showed an apparent extracranial carotid occlusion. DSA was available in 46 of these, showing an atherosclerotic cause in 13 (28%), dissection in 16 (35%), and pseudo-occlusion in 17 (37%). The sensitivity for detecting pseudo-occlusion on CTA was 82% (95% CI, 57-96) for both observers; specificity was 76% (95% CI, 56-90) and 86% (95% CI, 68-96) for observers 1 and 2, respectively. The κ value for interobserver agreement was .77, indicating substantial agreement. T-occlusions were more frequent in pseudo- than true occlusions (82% versus 21%, P < .001). CONCLUSIONS: On CTA, extracranial ICA pseudo-occlusions can be differentiated from true carotid occlusions.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Arteriosclerose Intracraniana/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/patologia , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/patologia , Estenose das Carótidas/patologia , Feminino , Humanos , Arteriosclerose Intracraniana/patologia , Masculino , Pessoa de Meia-Idade , Países Baixos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Sensibilidade e Especificidade , Acidente Vascular Cerebral/patologia
5.
J Neurooncol ; 138(1): 133-139, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29392588

RESUMO

To assess the applicability of perfusion-weighted (PWI) magnetic resonance (MR) imaging in clinical practice, as well as to evaluate the changes in PWI in brain metastases before and after stereotactic radiotherapy (SRT), and to correlate these changes to tumor status on conventional MR imaging. Serial MR images at baseline and at least 3 and 6 months after SRT were retrospectively evaluated. Size of metastases and the relative cerebral blood volume (rCBV), assessed with subjective visual inspection in the contrast enhanced area, were evaluated at each time point. Tumor behavior of metastases was categorized into four groups based on predefined changes on MRI during follow-up, or on histologically confirmed diagnosis; progressive disease (PD), pseudoprogression (PsPD), non-progressive disease (non-PD) and progression unspecified (PU). Twenty-six patients with 42 metastases were included. Fifteen percent (26/168) of all PW images could not be evaluated due to localization near large vessels or the scalp, presence of hemorrhage artefacts, and in 31% (52/168) due to unmeasurable residual metastases. The most common pattern (52%, 13/25 metastases) showed a high rCBV at baseline and low rCBV during follow-up, occurring in metastases with non-PD (23%, 3/13), PsPD (38%, 5/13) and PU (38%, 5/13). Including only metastases with a definite outcome generally showed low rCBV in PsPD or non-PD, and high rCBV in PD. Although non-PD and PsPD may be distinguished from PD after SRT using the PW images, the large proportion of images that could not be assessed due to artefacts and size severely hampers value of PWI in predicting tumor response after SRT.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/secundário , Angiografia por Ressonância Magnética/métodos , Radiocirurgia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estatísticas não Paramétricas
6.
AJNR Am J Neuroradiol ; 37(11): 2037-2042, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27418474

RESUMO

BACKGROUND AND PURPOSE: Collateral flow is associated with clinical outcome after acute ischemic stroke and may serve as a parameter for patient selection for intra-arterial therapy. In clinical trials, DSA and CTA are 2 imaging modalities commonly used to assess collateral flow. We aimed to determine the agreement between collateral flow assessment on CTA and DSA and their respective associations with clinical outcome. MATERIALS AND METHODS: Patients randomized in MR CLEAN with middle cerebral artery occlusion and both baseline CTA images and complete DSA runs were included. Collateral flow on CTA and DSA was graded 0 (absent) to 3 (good). Quadratic weighted κ statistics determined agreement between both methods. The association of both modalities with mRS at 90 days was assessed. Also, association between the dichotomized collateral score and mRS 0-2 (functional independence) was ascertained. RESULTS: Of 45 patients with evaluable imaging data, collateral flow was graded on CTA as 0, 1, 2, 3 for 3, 10, 20, and 12 patients, respectively, and on DSA for 12, 17, 10, and 6 patients, respectively. The κ-value was 0.24 (95% CI, 0.16-0.32). The overall proportion of agreement was 24% (95% CI, 0.12-0.38). The adjusted odds ratio for favorable outcome on mRS was 2.27 and 1.29 for CTA and DSA, respectively. The relationship between the dichotomized collateral score and mRS 0-2 was significant for CTA (P = .01), but not for DSA (P = .77). CONCLUSIONS: Commonly applied collateral flow assessment on CTA and DSA showed large differences, indicating that these techniques are not interchangeable. CTA was significantly associated with mRS at 90 days, whereas DSA was not.

7.
Eur J Neurol ; 23(10): 1528-33, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27424939

RESUMO

BACKGROUND AND PURPOSE: Conventional magnetic resonance imaging (MRI) has limited value for differentiation of true tumor progression and pseudoprogression in treated glioblastoma multiforme (GBM). Perfusion weighted imaging (PWI) may be helpful in the differentiation of these two phenomena. Here interobserver variability in routine radiological evaluation of GBM patients is assessed using MRI, including PWI. METHODS: Three experienced neuroradiologists evaluated MR scans of 28 GBM patients during temozolomide chemoradiotherapy at three time points: preoperative (MR1) and postoperative (MR2) MR scan and the follow-up MR scan after three cycles of adjuvant temozolomide (MR3). Tumor size was measured both on T1 post-contrast and T2 weighted images according to the Response Assessment in Neuro-Oncology criteria. PW images of MR3 were evaluated by visual inspection of relative cerebral blood volume (rCBV) color maps and by quantitative rCBV measurements of enhancing areas with highest rCBV. Image interpretability of PW images was also scored. Finally, the neuroradiologists gave a conclusion on tumor status, based on the interpretation of both T1 and T2 weighted images (MR1, MR2 and MR3) in combination with PWI (MR3). RESULTS: Interobserver agreement on visual interpretation of rCBV maps was good (κ = 0.63) but poor on quantitative rCBV measurements and on interpretability of perfusion images (intraclass correlation coefficient 0.37 and κ = 0.23, respectively). Interobserver agreement on the overall conclusion of tumor status was moderate (κ = 0.48). CONCLUSIONS: Interobserver agreement on the visual interpretation of PWI color maps was good. However, overall interpretation of MR scans (using both conventional and PW images) showed considerable interobserver variability. Therefore, caution should be applied when interpreting MRI results during chemoradiation therapy.


Assuntos
Glioblastoma/diagnóstico por imagem , Imageamento por Ressonância Magnética/normas , Humanos , Angiografia por Ressonância Magnética/normas , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos
8.
Eur J Neurol ; 23(2): 290-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26031667

RESUMO

BACKGROUND AND PURPOSE: An elevated international normalized ratio (INR) of >1.7 is a contraindication for the use of intravenous thrombolytics in acute ischaemic stroke. Local intra-arterial therapy (IAT) is considered a safe alternative. The safety and outcome of IAT were investigated in patients with acute ischaemic stroke using oral anticoagulants (OACs). METHODS: Data were obtained from a large national Dutch database on IAT in acute stroke patients. Patients were categorized according to the INR: >1.7 and ≤1.7. Primary outcome was symptomatic intracerebral hemorrhage (sICH), defined as deterioration in the National Institutes of Health Stroke Scale score of ≥4 and ICH on brain imaging. Secondary outcomes were clinical outcome at discharge and 3 months. Occurrence of outcomes was compared with risk ratios and corresponding 95% confidence intervals. Further, a systematic review and meta-analysis on sICH risk in acute stroke patients on OACs treated with IAT was performed. RESULTS: Four hundred and fifty-six patients were included. Eighteen patients had an INR > 1.7 with a median INR of 2.4 (range 1.8-4.1). One patient (6%) in the INR > 1.7 group developed a sICH compared with 53 patients (12%) in the INR ≤ 1.7 group (risk ratio 0.49, 95% confidence interval 0.07-3.13). Clinical outcomes did not differ between the two groups. Our meta-analysis showed a first week sICH risk of 8.1% (95% confidence interval 3.9%-17.1%) in stroke patients with elevated INR treated with IAT. CONCLUSION: The use of OACs, leading to an INR > 1.7, did not seem to increase the risk of an sICH in patients with an acute stroke treated with IAT.


Assuntos
Anticoagulantes/farmacologia , Isquemia Encefálica/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Acidente Vascular Cerebral/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Criança , Estudos de Coortes , Feminino , Humanos , Infusões Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
9.
Interv Neuroradiol ; 21(6): 715-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26464287

RESUMO

We describe a case of intra-arterial treatment (IAT) of acute posterior circulation occlusion in a patient with a persistent primitive trigeminal artery (PPTA). The patient presented with an acute left sided hemiparesis and loss of consciousness (Glasgow coma score of 5). Computed tomography angiography showed an acute occlusion of the right internal carotid artery (ICA), the PPTA, distal basilar artery (BA), right posterior cerebral artery (PCA), and right superior cerebellar artery (SCA). Stent-retriever assisted thrombectomy was not considered possible through the hypoplastic proximal BA. After passage of the proximal ICA occlusion, the right PCA and SCA were recanalized through the PPTA, with a single thrombectomy procedure. Ten days after intervention patient was discharged scoring optimal EMV with only a mild facial and left hand paresis remaining. PPTA is a persistent embryological carotid-basilar connection. Knowledge of existing (embryonic) variants in neurovascular anatomy is essential when planning and performing acute neurointerventional procedures.


Assuntos
Doenças das Artérias Carótidas/cirurgia , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Idoso , Artéria Basilar , Doenças das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Interna , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Humanos , Masculino , Artéria Cerebral Posterior , Acidente Vascular Cerebral/diagnóstico por imagem
10.
Acta Neurol Scand ; 131(3): 164-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25312840

RESUMO

Patients with acute severe headache may have a secondary form of headache. Standard head computer tomography (CT) and cerebrospinal fluid (CSF) examination are often performed in the absence of neurological deficits to exclude subarachnoid hemorrhage (SAH). Increasingly, patients undergo subsequent CT angiography (CTA) to exclude cerebral venous thrombosis (CVT), dissection or reversible cerebral vasoconstriction syndrome (RCVS). It is unknown whether this additional imaging increases diagnostic yield. We aimed to evaluate the yield of CTA in patients with acute severe headache with normal neurological examination and no abnormalities at standard CT and CSF analysis. We included consecutive patients presenting to the emergency room between January 2008 and May 2011 with acute severe headache and without abnormalities at neurological examination, CT and CSF research, who received a CTA in the diagnostic process in our teaching hospital. All scans were rereviewed by an experienced neuroradiologist. We included 70 patients, 71% were women and average age was 45 years. We found a vascular abnormality in 13 (19%) of our patients. Four had either a prior aneurysm or CVT. Eight patients had an unruptured intracranial aneurysm (UIA) on CTA (11%), two had CVT (3%), two had RCVS (3%) and one had cerebral ischemia (1%). We found a high percentage of vascular abnormalities. A third of these patients had a prior episode of either an aneurysm or CVT. In patients with a history of UIA or CVT performing CTA despite normal CT and LP therefore seems warranted. A prospective study to delineate indications for CTA is needed.


Assuntos
Angiografia Cerebral/métodos , Cefaleia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Cefaleia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Strahlenther Onkol ; 188(8): 696-701, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22722818

RESUMO

PURPOSE: The 1-year local control rates after single-fraction stereotactic radiotherapy (SRT) for brain metastases > 3 cm diameter are less than 70%, but with fractionated SRT (FSRT) higher local control rates have been reported. The purpose of this study was to compare our treatment results with SRT and FSRT for large brain metastases. MATERIALS AND METHODS: In two consecutive periods, 41 patients with 46 brain metastases received SRT with 1 fraction of 15 Gy, while 51 patients with 65 brain metastases received FSRT with 3 fractions of 8 Gy. We included patients with brain metastases with a planning target volume of > 13 cm(3) or metastases in the brainstem. RESULTS: The minimum follow-up of patients still alive was 22 months. Comparing 1 fraction of 15 Gy with 3 fractions of 8 Gy, the 1-year rates of freedom from any local progression (54% and 61%, p = 0.93) and pseudo progression (85% and 75%, p = 0.25) were not significantly different. Overall survival rates were also not different. CONCLUSION: The 1-year local progression and pseudo progression rates after 1 fraction of 15 Gy or 3 fractions of 8 Gy for large brain metastases and metastases in the brainstem are similar. For better local control rates, FSRT schemes with a higher biological equivalent dose may be necessary.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Neoplasias da Mama/cirurgia , Fracionamento da Dose de Radiação , Neoplasias Pulmonares/cirurgia , Melanoma/secundário , Melanoma/cirurgia , Radiocirurgia/métodos , Neoplasias Cutâneas/cirurgia , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Avaliação de Estado de Karnofsky , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Carga Tumoral
12.
Clin Radiol ; 66(1): 25-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21147295

RESUMO

AIM: To evaluate the interobserver agreement on magnetic resonance imaging (MRI) evaluation of herniated discs, spondylotic neuroforaminal stenosis, and root compression in patients with recent onset cervical radiculopathy and in addition, to assess the added value of disclosure of clinical information to interobserver agreement. MATERIALS AND METHODS: The MRI images of 82 patients with less than 1 month of symptoms and signs of cervical radiculopathy were evaluated independently by two neuroradiologists who were unaware of clinical findings. MRI analysis was repeated after disclosure of clinical information. Interobserver agreement was calculated using kappa statistics. RESULTS: The kappa score for evaluation of herniated discs and of spondylotic foramen stenosis was 0.59 and 0.63, respectively. A kappa score of 0.67 was found for the presence of root compression. After disclosure of clinical information kappa scores increased slightly: from 0.59 to 0.62 for the detection of herniated discs, from 0.63 to 0.66 for spondylotic foramen stenosis, and from 0.67 to 0.76 for root compression. CONCLUSION: Interobserver reliability of MRI evaluation in patients with cervical radiculopathy was substantial for root compression, with or without clinical information. Agreement on the cause of the compression, i.e., herniated disc or spondylotic foraminal stenosis, was lower.


Assuntos
Vértebras Cervicais , Deslocamento do Disco Intervertebral/diagnóstico , Imageamento por Ressonância Magnética/normas , Radiculopatia/diagnóstico , Estenose Espinal/diagnóstico , Feminino , Humanos , Deslocamento do Disco Intervertebral/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neurorradiografia/métodos , Neurorradiografia/normas , Variações Dependentes do Observador , Radiculopatia/patologia , Sensibilidade e Especificidade , Conduta Expectante
13.
J Neurol ; 255(4): 551-60, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18283398

RESUMO

OBJECTIVE: The authors describe their experience in treating 22 children with a single brain arteriovenous malformation (bAVM) using a dedicated LINAC stereotactic radiosurgery unit. METHODS: The findings of 22 consecutive patients < or = 18 years of age who underwent radiosurgery for a single bAVM and with at least 24 months of follow-up, or earlier proven obliteration,were reviewed. The median age at radiosurgery was 13.8 years,with a hemorrhagic presentation in 86%. Median bAVM-volume was 1.8 ml, with a median prescribed marginal dose of 19.0 Gy. RESULTS: The crude complete obliteration-rate was 68% (n = 15) after a median follow-up of 24 months. The actuarial obliteration- rate was 45 % after two years and 64 % after three years. Patients with a radiosurgery-based AVM score < or = 1 more frequently had an excellent outcome than patients with a bAVM score > 1 (71% vs. 20%, P = 0.12), as well as an increased obliteration rate (P = 0.03) One patient died from a bAVM-related hemorrhage 27 months after radiosurgery, representing a postradiosurgery hemorrhage rate of 1.3%/year for the complete followup interval. Overall outcome was good to excellent in 68% (n = 15). Radiation-induced changes on MR imaging were seen in 36% (n = 8) after a median interval of 12.5 months, resulting in deterioration of pre-existing neurological symptoms in one patient. CONCLUSIONS: Radiosurgery is a relatively effective, minimally invasive treatment for small bAVMs in children. The rebleeding rate is low, provided that known predilection places for bleeding had been endovascularly eliminated.Our overall results compare unfavourably to recent pediatric microsurgical series, although comparison between series remains imprecise. Nevertheless, when treatment is indicated in a child with a bAVM that is amenable to both microsurgery or radiosurgery, microsurgery should carefully be advocated over radiosurgery, because of its immediate risk reduction.


Assuntos
Artérias Cerebrais/anormalidades , Artérias Cerebrais/efeitos da radiação , Malformações Arteriovenosas Intracranianas/cirurgia , Radiocirurgia/métodos , Radiocirurgia/estatística & dados numéricos , Adolescente , Fatores Etários , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Encéfalo/cirurgia , Angiografia Cerebral , Artérias Cerebrais/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/cirurgia , Criança , Estudos de Coortes , Feminino , Seguimentos , Humanos , Malformações Arteriovenosas Intracranianas/patologia , Malformações Arteriovenosas Intracranianas/fisiopatologia , Masculino , Hemorragia Pós-Operatória/mortalidade , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
14.
Acta Neurochir (Wien) ; 148(9): 1005-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16770516

RESUMO

Idiopathic transdural spinal cord herniation is a rare but treatable cause of thoracic myelopathy caused by herniation of the spinal cord through a defect in the dura. The diagnosis is frequently missed or delayed, but the latest imaging techniques can document spinal cord herniation through a dural defect. Surgical treatment, consisting of reducing the herniation by closing the dural defect or widening the aperture to prevent spinal cord compression, is rather successful. We describe a new technique to untether the spinal cord by wrapping a dura graft around the myelum to prevent recurrent transdural herniation. Two patients and a review of the literature are discussed. We conclude that high-resolution T2 magnetic resonance imaging is the best imaging modality to detect the entity, and wrapping the myelum is an effective surgical technique to untether the spinal cord.


Assuntos
Dura-Máter/cirurgia , Dura-Máter/transplante , Herniorrafia , Procedimentos Neurocirúrgicos/métodos , Doenças da Medula Espinal/cirurgia , Medula Espinal/cirurgia , Adulto , Síndrome de Brown-Séquard/etiologia , Síndrome de Brown-Séquard/fisiopatologia , Síndrome de Brown-Séquard/cirurgia , Progressão da Doença , Dura-Máter/patologia , Espaço Epidural/patologia , Espaço Epidural/fisiopatologia , Espaço Epidural/cirurgia , Feminino , Hérnia/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Doenças da Medula Espinal/etiologia , Doenças da Medula Espinal/fisiopatologia , Transplantes , Resultado do Tratamento
15.
J Neurol Sci ; 233(1-2): 199-202, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15949505

RESUMO

Atrophy is one of the hallmarks in multiple sclerosis (MS), especially in the advanced stage. Modern magnetic resonance (MR) techniques can reliably measure brain volume and changes therein. Depending on the technique used, changes of about 1% may be detected. Clinicoradiological studies show good correlation between atrophy measures, both in brain and spinal cord, and clinical measures. The exact relationship between focal MS lesions and global atrophy has yet to be established. Number of lesions early in the disease seems to predict later atrophy. The exact pathomechanism of atrophy in MS probably may be explained by both demyelination and axonal loss--which may occur independently from each other.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/patologia , Atrofia/patologia , Humanos
16.
Neurology ; 62(2): 226-33, 2004 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-14745058

RESUMO

OBJECTIVE: The most recent diagnostic criteria for multiple sclerosis (MS) ascertain that findings from spinal cord MRI can be used to demonstrate dissemination in space. Because little is known about the prevalence and characteristics of cord lesions early in the disease, the authors studied the prevalence of spinal cord abnormalities in patients with early-stage MS and assessed their impact on diagnostic classification. METHODS: The brains and spinal cords of 104 recently diagnosed patients with MS were examined. Median interval between first symptom and diagnosis was 18.4 months. The brain MRI protocol included before and after gadolinium axial T1-weighted conventional spin-echo sequences and dual-echo spin-echo images. For spinal cord MRI, sagittal cardiac-triggered dual-echo T2-weighted and sagittal T1-weighted spin-echo images were included. Clinical assessment for each patient included age, sex, clinical signs for spinal cord involvement, and Expanded Disability Status Scale. RESULTS: Abnormal cord MRIs were found in 83% of patients, usually with only focal lesions. Diffuse cord abnormalities were found in 13% of patients, although in isolation they were found in only three patients. Focal cord lesions were often multiple (median number, 3.0), small (median, 0.8 vertebral segments), and primarily (56.4%) situated in the cervical spinal cord. In 68 of 104 patients (65.4%), two or more focal lesions were visible on spinal cord images. The criteria for dissemination in space, as defined in the McDonald criteria for the brain, were met in only 66.3% of the patients. This percentage increased to 84.6% when spinal cord MRI abnormalities were also included. CONCLUSION: Spinal cord abnormalities are prevalent in patients with early-stage MS, have distinct morphologic characteristics, and help to determine dissemination in space at time of diagnosis.


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla/patologia , Medula Espinal/patologia , Adulto , Encéfalo/patologia , Meios de Contraste , Feminino , Gadolínio , Humanos , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos
17.
Neurology ; 59(11): 1766-71, 2002 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-12473766

RESUMO

OBJECTIVE: To determine the degree of axonal damage in relationship to signal abnormalities on T2-weighted high-resolution MRI in spinal cord tissue of patients with MS. METHODS: Spinal cord specimens of nine patients with MS and four controls were imaged at high resolution (4.7 T) in an axial plane and scored for lesions with increased signal intensity (SI). Histopathologic sections were cut and immunostained with NE14 (neurofilament marker) and Luxol fast blue (myelin stain). For each area, axonal density and diameter were quantified; axonal irregularity, NE14 axonal staining intensity, and myelin content were semiquantitatively scored. Included were 209 areas from MS cases and 109 areas from control cases distributed over lateral, posterior, and anterior columns. RESULTS: In control cases, no SI changes were found, average density of axons was 26,989/mm(2), average diameter was 1.1 micro m, and all scores for axonal irregularity, NE14 staining intensity, and myelin were normal. In MS cases, areas with increased SI were found, average axonal density was 11,807/mm(2) (p < 0.0001), and average axonal diameter 2.0 micro m (p = 0.001). Areas with high SI on MRI had lowest axonal density (average count: 10,504/mm(2); range: 3,433 to 26,325/mm(2)), largest diameter (average: 2.3 micro m; range: 1.0 to 4.0 micro m), and highest axonal irregularity and NE14 staining intensity compared to normal appearing cord tissue (NACT). However, NACT of MS cases also had lower axonal density (14,158/mm(2)) and higher average axonal diameter (1.6 micro m) than controls. CONCLUSIONS: Marked axonal loss occurs in MS spinal cords, largely independent of the degree of signal abnormality on T2-weighted MRI.


Assuntos
Axônios/patologia , Imageamento por Ressonância Magnética , Esclerose Múltipla/patologia , Medula Espinal/patologia , Adulto , Idoso , Tamanho Celular , Corantes , Feminino , Humanos , Imuno-Histoquímica , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Bainha de Mielina/patologia
18.
Arch Neurol ; 58(1): 76-81, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11176939

RESUMO

CONTEXT: Hypointense lesions on T1-weighted spin-echo magnetic resonance images (T1 lesions) represent destructive multiple sclerosis (MS) lesions, consisting of axonal loss and matrix destruction. These lesions are being used as a secondary outcome measure in phase III clinical trials. Clinical determinants of T1 lesions may differ between subgroups of patients with MS and subsequently may have implications for the selection of patients for clinical trials. OBJECTIVE: To determine if clinical characteristics of patients with MS are related to T1 lesion volume. DESIGN: A survey of 138 patients with MS (52 with relapsing-remitting MS, 44 with secondary progressive MS, and 42 with primary progressive MS). SETTING: The Magnetic Resonance Center for Multiple Sclerosis Research, University Hospital "Vrije Universiteit," Amsterdam, the Netherlands. MAIN OUTCOME MEASURES: Type of MS, Expanded Disability Status Scale (EDSS) score, sex, age at first symptoms, and T1 lesion volume. RESULTS: Patients with secondary progressive MS have the highest T1 lesion volume. Patients with relapsing-remitting MS have a lower T1/T2 ratio than patients with secondary progressive MS and patients with primary progressive MS. In patients with relapsing-remitting MS and secondary progressive MS, T1 lesion volume relates to disease duration and EDSS score, while in patients with primary progressive MS sex is important. A trend toward higher T1 lesion volume was shown for male patients with primary progressive MS when compared with female patients with primary progressive MS (1.0 cm(3) vs 0.3 cm(3), P=.03); a trend toward higher T1 lesion volume was found with age at onset in patients with relapsing-remitting MS and in patients with primary progressive MS. CONCLUSIONS: In patients with MS different clinical characteristics associate with T1 lesion volume, suggesting a more destructive type of lesions in certain subgroups. A possible sex difference in (destructive) lesion development on magnetic resonance imaging should be evaluated in more detail, preferably in a cohort.


Assuntos
Encéfalo/patologia , Imagem Ecoplanar/métodos , Esclerose Múltipla Crônica Progressiva/diagnóstico , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Adulto , Fatores Etários , Axônios/patologia , Meios de Contraste , Estudos Transversais , Avaliação da Deficiência , Progressão da Doença , Feminino , Gadolínio DTPA , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores Sexuais , Inquéritos e Questionários
19.
Eur Radiol ; 10(5): 753-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10823627

RESUMO

The current optimal imaging protocol in spinal cord MR imaging in patients with multiple sclerosis includes a long TR conventional spin-echo (CSE) sequence, requiring long acquisition times. Using short tau inversion recovery fast spin-echo (fast STIR) sequences both acquisition time can be shortened and sensitivity in the detection of multiple sclerosis (MS) abnormalities can be increased. This study compares both sequences for the potential to detect both focal and diffuse spinal abnormalities. Spinal cords of 5 volunteers and 20 MS patients were studied at 1.0 T. Magnetic resonance imaging included cardiac-gated sagittal dual-echo CSE and a cardiac-gated fast STIR sequence. Images were scored regarding number, size, and location of focal lesions, diffuse abnormalities and presence/hindrance of artifacts by two experienced radiologists. Examinations were scored as being definitely normal, indeterminate, or definitely abnormal. Interobserver agreement regarding focal lesions was higher for CSE (kappa = 0.67) than for fast STIR (kappa = 0.57) but did not differ significantly. Of all focal lesions scored in consensus, 47% were scored on both sequences, 31% were only detected by fast STIR, and 22% only by dual-echo CSE (n.s.). Interobserver agreement for diffuse abnormalities was lower with fast STIR (kappa = 0.48) than dual-echo CSE (kappa = 0.65; n. s.). After consensus, fast STIR showed in 10 patients diffuse abnormalities and dual-echo CSE in 3. After consensus, in 19 of 20 patients dual-echo CSE scans were considered as definitely abnormal compared with 17 for fast STIR. The fast STIR sequence is a useful adjunct to dual-echo CSE in detecting focal abnormalities and is helpful in detecting diffuse MS abnormalities in the spinal cord. Due to the frequent occurrence of artifacts and the lower observer concordance, fast STIR cannot be used alone.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico , Doenças da Medula Espinal/diagnóstico , Análise de Variância , Artefatos , Humanos , Aumento da Imagem/métodos , Variações Dependentes do Observador , Sensibilidade e Especificidade , Medula Espinal/patologia , Estatísticas não Paramétricas , Fatores de Tempo
20.
J Neuroimaging ; 10(2): 67-72, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10800258

RESUMO

The authors compare the spinal cord magnetization transfer ratio (MTR) of multiple sclerosis (MS) patients to healthy volunteers, relate MTR to spinal cord atrophy, and relate these and other magnetic resonance (MR) imaging parameters to disability. Sixty-five patients with MS (14 relapsing remitting [RR], 34 secondary progressive [SP], and 17 primary progressive [PP] MS), and 9 healthy volunteers were studied using MR at 1.0 T. Disability of the patients was assessed using the expanded disability status scale (EDSS). Magnetic resonance parameters were upper spinal cord MTR, number of focal spinal lesions, presence of diffuse abnormalities, and spinal cord cross-sectional area (CSA). Correlations were assessed using Spearman's rank correlation coefficient (r). Magnetization transfer ratio was higher in the controls (median, 33%; range, 30%-38%) than in patients with MS (median, 30%; range, 16-36; p < 0.05). In patients with MS EDSS correlated with spinal cord MTR, albeit weakly (r = -0.25, p < 0.05). Correlation between EDSS and spinal cord CSA was better (SRCC = -0.40, p < 0.01). No correlation was found between MTR and CSA (r = 0.1, p = 0.4). Combining MTR with spinal cord CSA improved correlation with EDSS (r = -0.46, p < 0.001), suggesting an independent correlation between disability and these 2 MR parameters. Expanded disability status scale scores were higher in patients who had diffuse spinal cord abnormality regardless of focal lesions (median, 6; range, 1.5-7.5) than in patients without diffuse abnormalities (median, 3.5; range, 0-8; p < 0.01). CSA was lower in patients with diffuse spinal cord abnormality (median, 62; range, 46-89 mm2) than in patients without diffuse abnormalities (median, 73; range, 47-89 mm2; p < 0.01). MTR was slightly lower in patients with diffuse spinal cord abnormalities (median, 29; range, 21%-33%) than in patients without diffuse abnormalities (median, 31; range, 16-36; t-test, p < 0.05).


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla Crônica Progressiva/patologia , Medula Espinal/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/patologia
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