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2.
Radiol Artif Intell ; 5(5): e230034, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37795143

RESUMO

This dataset is composed of cervical spine CT images with annotations related to fractures; it is available at https://www.kaggle.com/competitions/rsna-2022-cervical-spine-fracture-detection/.

3.
Transl Oncol ; 14(10): 101188, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34343854

RESUMO

Biomarkers which can identify Diffuse Large B-Cell Lymphoma (DLBCL) likely to be refractory to first-line therapy are essential for selecting this population prior to therapy initiation to offer alternate therapeutic options that can improve prognosis. We tested the ability of a CT-based radiomics approach with machine learning to predict Primary Treatment Failure (PTF)-DLBCL from initial imaging evaluation. Twenty-six refractory patients were matched to 26 non-refractory patients, yielding 180 lymph nodes for analysis. Manual 3D delineation of the total node volume was performed by two independent readers to test the reproducibility. Then, 1218 hand-crafted radiomic features were extracted. The Random Forests machine learning approach was used as a classifier for constructing the prediction models. Seventy percent of the nodes were randomly assigned to a training set and the remaining 30% were assigned to an independent test set. The final model was tested on the dataset from the 2 readers, showing a mean accuracy, sensitivity and specificity of 73%, 62% and 82%, respectively, for distinguishing between refractory and non-refractory patients. The area under the receiver operating characteristic curve (AUC) was 0.83 and 0.79 for the two readers. We conclude that machine learning CT-based radiomics analysis is able to identify a priori PTF-DLBCL with a good accuracy.

4.
J Neurosurg ; 134(3): 971-982, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32217799

RESUMO

OBJECTIVE: Intravenous (IV) milrinone is a promising option for the treatment of cerebral vasospasm with delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH). However, data remain limited on the efficacy of treating cases that are refractory to standard therapy with IV milrinone. The aim of this study was to determine predictors of refractory vasospasm/DCI despite treatment with IV milrinone, and to analyze the outcome of rescue therapy with intraarterial (IA) milrinone and/or mechanical angioplasty. METHODS: The authors conducted a retrospective cohort study of all patients with aSAH admitted between 2010 and 2016 to the Montreal Neurological Institute and Hospital. Patients were stratified into 3 groups: no DCI, standard therapy, and rescue therapy. The primary outcome was frequency of DCI-related cerebral infarction identified on neuroimaging before hospital discharge. Secondary outcomes included functional outcome reported as modified Rankin Scale (mRS) score, and segment reversal of refractory vasospasm. RESULTS: The cohort included 322 patients: 212 in the no DCI group, 89 in the standard therapy group, and 21 in the rescue therapy group. Approximately half (52%, 168/322) were admitted with poor-grade aSAH at treatment decision (World Federation of Neurosurgical Societies grade III-V). Among patients with DCI and imaging assessing severity of vasospasm, 62% (68/109) had moderate/severe radiological vasospasm on DCI presentation. Nineteen percent (21/110) of patients had refractory vasospasm/DCI and were treated with rescue therapy. Targeted rescue therapy with IA milrinone reversed 32% (29/91) of the refractory vasospastic vessels, and 76% (16/21) of those patients experienced significant improvement in their neurological status within 24 hours of initiating therapy. Moderate/severe radiological vasospasm independently predicted the need for rescue therapy (OR 27, 95% CI 8.01-112). Of patients with neuroimaging before discharge, 40% (112/277) had developed new cerebral infarcts, and only 21% (23/112) of these were vasospasm-related. Overall, 65% (204/314) of patients had a favorable functional outcome (mRS score 0-2) assessed at a median of 4 months (interquartile range 2-8 months) after aSAH, and there was no difference in functional outcome between the 3 groups (p = 0.512). CONCLUSIONS: The aggressive use of milrinone was safe and effective based on this retrospective study cohort and is a promising therapy for the treatment of vasospasm/DCI after aSAH.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Milrinona/uso terapêutico , Vasodilatadores/uso terapêutico , Vasoespasmo Intracraniano/tratamento farmacológico , Adulto , Idoso , Angioplastia , Isquemia Encefálica/etiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Injeções Intra-Arteriais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vasoespasmo Intracraniano/complicações
5.
Reg Anesth Pain Med ; 43(4): 367-371, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29346229

RESUMO

BACKGROUND AND OBJECTIVES: Accidental breach of the vertebral artery (VA) during the performance of cervical pain blocks can result in significant morbidity. Whereas anatomical variations have been described for the foraminal (V2) segment of the VA, those involving its V3 portion (between the C2 transverse process and dura) have not been investigated and may be of importance for procedures targeting the third occipital nerve or the lateral atlantoaxial joint. METHODS: Five hundred computed tomography angiograms of the neck performed in patients older than 50 years for the management of cerebrovascular accident or cervical trauma (between January 2010 and May 2016) were retrospectively and independently reviewed by 2 neuroradiologists. Courses of the VA in relation to the lateral aspect of the C2/C3 joint and the posterior surface of the C1/C2 joint were examined. For the latter, any medial encroachment of the VA (or one of its branches) was noted. The presence of a VA loop between C1 and C2 and its distance from the upper border of the superior articular process (SAP) of C3 were also recorded. If the VA loop coursed posteriorly, its position in relation to 6 fields found on the lateral aspects of the articular pillars of C2 and C3 was tabulated. RESULTS: At the C1/C2 level, the VA coursed medially over the lateral quarter of the dorsal joint surface in 1% of subjects (0.6% and 0.4% on the left and right sides, respectively; P = 0.998). A VA loop originating between C1 and C2 was found to travel posteroinferiorly over the anterolateral aspect of the inferior articular pillar of C2 in 55.5% of patients on the left and 41.9% on the right side (P < 0.001), as well as over the SAP of C3 in 0.4% of subjects. When present in the quadrant immediately cephalad to the C3 SAP, VA loops coursed within 2.0 ± 1.5 and 3.3 ± 2.5 mm on the left and right sides, respectively, of its superior aspect (P < 0.001). CONCLUSIONS: The VA commonly travels adjacent to areas targeted by third occipital nerve procedures and more rarely over the access point for lateral atlantoaxial joint injections. Modifications to existing techniques may reduce the risk of accidental VA breach.


Assuntos
Vértebras Cervicais/anatomia & histologia , Vértebras Cervicais/diagnóstico por imagem , Artéria Vertebral/anatomia & histologia , Artéria Vertebral/diagnóstico por imagem , Articulação Atlantoaxial/anatomia & histologia , Articulação Atlantoaxial/irrigação sanguínea , Articulação Atlantoaxial/diagnóstico por imagem , Vértebras Cervicais/irrigação sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Rev. colomb. radiol ; 22(1): 3117-3121, mar. 2011.
Artigo em Espanhol | LILACS | ID: lil-590891

RESUMO

Objetivos: Describir los hallazgos por imagen en tomografía computarizada (TAC ) y resonancia magnética (RM) en una paciente con estenosis del CAI. Describir el desarrollo embriológico de las estructuras del CAI y la historia natural de la estenosis del CAI . Métodos: Se presenta el caso de una paciente de 4 años de edad con diagnóstico de cardiopatía congénita, hipoacusia neurosensorial (HNS ) y otitis media recurrente bilateral, y a quien se realizó TAC del hueso temporal con imágenes axiales y reconstrucciones coronales, en las cuales se observa disminución del diámetro de la luz del CAI izquierdo (menor de 2 mm), ausencia del CAI derecho y estructuras del oído interno de características normales, compatibles con estenosis del CAI izquierdo. Las imágenes de RM demuestran la estenosis del CAI izquierdo, sin observarse las estructuras nerviosas dentro de éste, compatible con hipoplasia/aplasia del nervio vestibulococlear. Resultados: Se describen brevemente la patología, el origen embriológico y la importancia de la asociación de la estenosis delCAI a hipoplasia/aplasia del nervio vestibulococlear en el diagnóstico diferencial de las causas de HNS , que contraindican la realización de implante coclear. Conclusiones: La estenosis del CAI e hipoplasia/aplasia del nervio vestibulococlear es un diagnóstico para tener en cuenta dentro de las causas de HNS , y su diagnóstico puede realizarse a través de TAC y de RM.


Objectives: To describe the computed tomography (CT) and magnetic resonance (MR) findings in a patient with a diagnosis of internal auditory canal (IAC) stenosis. To describe the embryological development of the IAC structures and the natural history of IAC stenosis. Methods: A 4 year old girl presents with sensorineural hearing loss and bilateral recurrent otitis media. The temporal bone CT shows diminished left IAC diameter (less than 2 mm),right IAC absence and normal inner ear structures. These findings are pathognomonic for left IAC stenosis. The MR findings include left IAC stenosis and IAC neural structures absence secondary to aplasia of the vestibulocochlear nerve on each IAC . Results: Hypoplasia/aplasia of the vestibulocochlear nerve in association with IAC stenosis is an important consideration in the differential diagnosis of sensorineural hearing loss, as it is a relative contraindication for cochlear implant placement. Conclusions: IAC stenosis and vestibulocochlear nerve hypoplasia/aplasia must be excluded as an etiology of sensorineural hearing loss. The diagnosis can be made by CT and MR.


Assuntos
Humanos , Perda Auditiva Neurossensorial , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
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