RESUMEN
PURPOSE: Visual interpretation of brain amyloid-ß (Aß) PET can be difficult in individuals with borderline Aß burden. Coregistration with individual MRI is recommended in these cases, which, however, is not always available. This study evaluated coregistration with the early perfusion frames acquired immediately after tracer injection to support the visual interpretation of the late Aß-frames in PET with 18F-flutemetamol (FMM). PATIENTS AND METHODS: Fifty dual-time-window FMM-PET scans of cognitively normal subjects with 0 to 60 Centiloids were included retrospectively (70.1 ± 6.9 years, 56% female, MMSE score 28.9 ± 1.3, 42% APOE É4 carrier). Regional Aß load was scored with respect to a 6-point Likert scale by 3 independent raters in the 10 regions of interest recommended for FMM reading using 3 different settings: Aß image only, Aß image coregistered with MRI, and Aß image coregistered with the perfusion image. The impact of setting, within- and between-readers variability, region of interest, and Aß-status was tested by repeated-measure analysis of variance of the Likert score. RESULTS: The Centiloid scale ranged between 2 and 52 (interquartile range, 7-19). Support of visual scoring by the perfusion image resulted in the best discrimination between Aß-positive and Aß-negative cases, mainly by improved certainty of excluding Aß plaques in Aß-negative cases (P = 0.030). It also resulted in significantly higher between-rater agreement. The setting effect was most pronounced in the frontal lobe and in the posterior cingulate cortex/precuneus area (P = 0.005). CONCLUSIONS: The early perfusion image is a suitable alternative to T1-weighted MRI to support the visual interpretation of the late Aß image in FMM-PET.
Asunto(s)
Compuestos de Anilina , Benzotiazoles , Encéfalo , Tomografía de Emisión de Positrones , Humanos , Femenino , Masculino , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Benzotiazoles/farmacocinética , Imagen de Perfusión , Péptidos beta-Amiloides/metabolismo , Persona de Mediana Edad , Interpretación de Imagen Asistida por ComputadorRESUMEN
BACKGROUND AND AIM: Accurate interpretation of post-treatment imaging in head and neck malignancies poses a challenge due to treatment sequelae. Magnetic resonance (MR) perfusion helps in this scenario by evaluating the hemodynamic characteristics of lesions. This study aimed to elucidate the diagnostic efficacy of dynamic contrast-enhanced (DCE)-MR perfusion imaging in detecting recurrence in patients after they underwent definitive treatment for head and neck tumors. MATERIALS AND METHODS: Thirty patients who had received definitive curative-intent treatment for histopathology-proven malignant head and neck tumors and in whom recurrent tumor was detected on precontrast MR imaging (MRI) were accrued in the study. Patients underwent DCE-MR perfusion imaging. Time to peak (TTP), relative maximum enhancement (RME), and relative washout (RWO) ratio were calculated by using time-intensity curve (TIC). The diagnostic accuracy was compared with histopathology. RESULTS: A cut-off value of ≥125.3 for RME showed a sensitivity of 76.2% and specificity of 66.7% for differentiating post-radiation changes and recurrence. The optimal cut-off for RWO ratio was ≥-6.24 with a sensitivity of 76.2% and specificity of 55.6%. The optimal cut-off of TTP was ≤45.8 s with a sensitivity of 61.9% and specificity of 77.8%. Diagnostic accuracies of RME, RWO, and TTP were 73.3%, 70%, and 66.7%, respectively. CONCLUSIONS: DCE-MRI had significant diagnostic accuracy in detecting and differentiating recurrences. TIC analysis of high-temporal resolution DCE-MRI can provide information regarding microcirculation of tumors, and hence can be considered as an imaging modality of choice for assessment of early local tumor recurrence in head and neck tumors.
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Medios de Contraste , Neoplasias de Cabeza y Cuello , Recurrencia Local de Neoplasia , Humanos , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Anciano , Adulto , Imagen por Resonancia Magnética/métodos , Curva ROC , Angiografía por Resonancia Magnética/métodos , Imagen de Perfusión/métodosRESUMEN
This study aimed to evaluate the value of low-dose dual-input computed tomography perfusion (CTP) imaging in the differential diagnosis of benign and malignant pulmonary ground-glass opacity nodules (GGO). A retrospective study was conducted in patients with GGO who underwent CTP in our hospital from January 2021 to October 2023. All nodules were confirmed via pathological analysis or disappeared during follow-up. Postprocessing analysis was conducted using the dual-input perfusion mode (pulmonary artery and bronchial artery) of the body perfusion software to measure the perfusion parameters of the pulmonary GGOs. A total of 101 patients with pulmonary GGOs were enrolled in this study, including 43 benign and 58 malignant nodules. The dose length product of the CTP (348 mGy.cm) was < 75% of the diagnostic reference level of the unenhanced chest CT (470 mGy.cm). The effective radiation dose was 4.872 mSV. The blood flow (BF), blood volume (BV), mean transit time (MTT), and flow extraction product (FEP) of malignant nodules were higher than those of the benign nodules (p < 0.05). The FEP had the highest accuracy for the diagnosis of malignant nodules (area under the curve [AUC] = 0.821, 95% confidence interval [CI]: 0.735-0.908) followed by BV (AUV = 0.713, 95% CI 0.608-0.819), BF (AUC = 0.688, 95% CI 0.587-0.797), and MTT (AUC = 0.616, 95% CI 0.506-0.726). When the FEP was ≥ 19.12 mL/100 mL/min, the sensitivity was 91.5% and the specificity was 62.8%. To distinguish between benign nodules and malignant nodules, the AUC of the combination of BV and FEP was 0.816 (95% CI 0.728-0.903), whereas the AUC of the combination of BF, BV, MTT, and FEP was 0.814 (95% CI 0.729-0.900). Low-dose dual-input perfusion CT was extremely effective in distinguishing between benign from malignant pulmonary GGOs, with FEP exhibiting the highest diagnostic capability.
Asunto(s)
Neoplasias Pulmonares , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Persona de Mediana Edad , Diagnóstico Diferencial , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico , Estudios Retrospectivos , Anciano , Tomografía Computarizada por Rayos X/métodos , Adulto , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/patología , Imagen de Perfusión/métodos , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulos Pulmonares Múltiples/patología , Pulmón/diagnóstico por imagen , Pulmón/irrigación sanguínea , Pulmón/patología , Curva ROC , Dosis de RadiaciónRESUMEN
BACKGROUND: Intravenous tenecteplase increases reperfusion in patients with salvageable brain tissue on perfusion imaging and might have advantages over alteplase as a thrombolytic for ischaemic stroke. We aimed to assess the non-inferiority of tenecteplase versus alteplase on clinical outcomes in patients selected by use of perfusion imaging. METHODS: This international, multicentre, open-label, parallel-group, randomised, clinical non-inferiority trial enrolled patients from 35 hospitals in eight countries. Participants were aged 18 years or older, within 4·5 h of ischaemic stroke onset or last known well, were not being considered for endovascular thrombectomy, and met target mismatch criteria on brain perfusion imaging. Patients were randomly assigned (1:1) by use of a centralised web server with randomly permuted blocks to intravenous tenecteplase (0·25 mg/kg) or alteplase (0·90 mg/kg). The primary outcome was the proportion of patients without disability (modified Rankin Scale 0-1) at 3 months, assessed via masked review in both the intention-to-treat and per-protocol populations. We aimed to recruit 832 participants to yield 90% power (one-sided alpha=0·025) to detect a risk difference of 0·08, with an absolute non-inferiority margin of -0·03. The trial was registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613000243718, and the European Union Clinical Trials Register, EudraCT Number 2015-002657-36, and it is completed. FINDINGS: Recruitment ceased early following the announcement of other trial results showing non-inferiority of tenecteplase versus alteplase. Between March 21, 2014, and Oct 20, 2023, 680 patients were enrolled and randomly assigned to tenecteplase (n=339) and alteplase (n=341), all of whom were included in the intention-to-treat analysis (multiple imputation was used to account for missing primary outcome data for five patients). Protocol violations occurred in 74 participants, thus the per-protocol population comprised 601 people (295 in the tenecteplase group and 306 in the alteplase group). Participants had a median age of 74 years (IQR 63-82), baseline National Institutes of Health Stroke Scale score of 7 (4-11), and 260 (38%) were female. In the intention-to-treat analysis, the primary outcome occurred in 191 (57%) of 335 participants allocated to tenecteplase and 188 (55%) of 340 participants allocated to alteplase (standardised risk difference [SRD]=0·03 [95% CI -0·033 to 0·10], one-tailed pnon-inferiority=0·031). In the per-protocol analysis, the primary outcome occurred in 173 (59%) of 295 participants allocated to tenecteplase and 171 (56%) of 306 participants allocated to alteplase (SRD 0·05 [-0·02 to 0·12], one-tailed pnon-inferiority=0·01). Nine (3%) of 337 patients in the tenecteplase group and six (2%) of 340 in the alteplase group had symptomatic intracranial haemorrhage (unadjusted risk difference=0·01 [95% CI -0·01 to 0·03]) and 23 (7%) of 335 and 15 (4%) of 340 died within 90 days of starting treatment (SRD 0·02 [95% CI -0·02 to 0·05]). INTERPRETATION: The findings in our study provide further evidence to strengthen the assertion of the non-inferiority of tenecteplase to alteplase, specifically when perfusion imaging has been used to identify reperfusion-eligible stroke patients. Although non-inferiority was achieved in the per-protocol population, it was not reached in the intention-to-treat analysis, possibly due to sample size limtations. Nonetheless, large-scale implementation of perfusion CT to assist in patient selection for intravenous thrombolysis in the early time window was shown to be feasible. FUNDING: Australian National Health Medical Research Council; Boehringer Ingelheim.
Asunto(s)
Fibrinolíticos , Accidente Cerebrovascular Isquémico , Imagen de Perfusión , Tenecteplasa , Activador de Tejido Plasminógeno , Humanos , Tenecteplasa/uso terapéutico , Tenecteplasa/administración & dosificación , Masculino , Femenino , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Activador de Tejido Plasminógeno/uso terapéutico , Activador de Tejido Plasminógeno/administración & dosificación , Anciano , Fibrinolíticos/uso terapéutico , Fibrinolíticos/administración & dosificación , Persona de Mediana Edad , Imagen de Perfusión/métodos , Terapia Trombolítica/métodos , Resultado del Tratamiento , Anciano de 80 o más AñosRESUMEN
BACKGROUND AND OBJECTIVES: We recently developed a model (PROCEED) that predicts the occurrence of persistent perfusion deficit (PPD) at 24 hours in patients with incomplete angiographic reperfusion after thrombectomy. This study aims to externally validate the PROCEED model using prospectively acquired multicenter data. METHODS: Individual patient data for external validation were obtained from the Endovascular Therapy for Ischemic Stroke with Perfusion-Imaging Selection, Tenecteplase versus Alteplase Before Endovascular Therapy for Ischemic Stroke part 1 and 2 trials, and a prospective cohort of the Medical University of Graz. The model's primary outcome was the occurrence of PPD, defined as a focal, wedge-shaped perfusion delay on 24-hour follow-up perfusion imaging that corresponds to the capillary phase deficit on last angiographic series in patients with Asunto(s)
Reperfusión
, Trombectomía
, Humanos
, Trombectomía/métodos
, Masculino
, Femenino
, Anciano
, Persona de Mediana Edad
, Reperfusión/métodos
, Accidente Cerebrovascular Isquémico/cirugía
, Accidente Cerebrovascular Isquémico/diagnóstico por imagen
, Accidente Cerebrovascular Isquémico/terapia
, Imagen de Perfusión
, Estudios Prospectivos
, Circulación Cerebrovascular/fisiología
, Anciano de 80 o más Años
RESUMEN
In order to guide the formulation of post-stroke treatment strategy in time, it is necessary to have real-time feedback on collateral circulation and revascularization. Currently used near-infrared II (NIR-II) probes have inherent binding with endogenous albumin, resulting in significant background signals and uncontrollable pharmacokinetics. Therefore, the albumin-escaping properties of the new probe, IR-808AC, was designed, which achieved timely excretion and low background signal, enabling the short-term repeatable injection for visualization of cerebral vessels and perfusion. We further achieved continuous observation of changes in collateral vessels and perfusion during the 7-d period in middle cerebral artery occlusion mice using IR-808AC in vivo. Furthermore, using IR-808AC, we confirmed that remote ischemic conditioning could promote collateral vessels and perfusion. Finally, we evaluated the revascularization after thrombolysis on time in embolic stroke mice using IR-808AC. Overall, our study introduces a novel methodology for safe, non-invasive, and repeatable assessment of collateral circulation and revascularization in real-time that is crucial for the optimization of treatment strategies.
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Modelos Animales de Enfermedad , Accidente Cerebrovascular , Animales , Accidente Cerebrovascular/diagnóstico por imagen , Ratones , Masculino , Imagen de Perfusión/métodos , Arterias Cerebrales/diagnóstico por imagen , Ratones Endogámicos C57BL , Albúminas/química , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Espectroscopía Infrarroja Corta/métodos , Circulación ColateralRESUMEN
Brain death is defined as the complete and irreversible cessation of the entire brain function, including the brainstem. For the most part, the diagnosis is clinical, and ancillary testing is only needed when clinical criteria are not satisfied. Differences exist in brain death diagnosis policy in the confirmation of brain death with ancillary testing and the particular test used. Demonstration of the absence of cerebral circulation is a reliable indicator of brain death. Currently, there are no agreed-on universal criteria for ancillary imaging investigation. However, several guidelines and meta-analyses have referred to radionuclide imaging as the most reliable, accurate, and validated ancillary imaging procedure in the confirmation of brain death. Whenever available, lipophilic agents should be preferred using tomographic imaging in all or as needed. False results may occur because of slight temporal delays in flow-function interaction, and such findings may carry prognostic information. Detectable cerebral circulation in the clinical presence of brain death most probably indicates that the process of dying is not yet complete. The results of radionuclide studies may also suggest that the loss of viability in a significant proportion of brain tissue is not compatible with life.
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Muerte Encefálica , Circulación Cerebrovascular , Valor Predictivo de las Pruebas , Muerte Encefálica/diagnóstico por imagen , Humanos , Encéfalo/diagnóstico por imagen , Radiofármacos/administración & dosificación , Reproducibilidad de los Resultados , Imagen de Perfusión/métodos , PronósticoRESUMEN
Arterial spin-labeled perfusion and blood oxygenation level-dependent functional MRI are indispensable tools for noninvasive human brain imaging in clinical and cognitive neuroscience, yet concerns persist regarding the reliability and reproducibility of functional MRI findings. The circadian rhythm is known to play a significant role in physiological and psychological responses, leading to variability in brain function at different times of the day. Despite this, test-retest reliability of brain function across different times of the day remains poorly understood. This study examined the test-retest reliability of six repeated cerebral blood flow measurements using arterial spin-labeled perfusion imaging both at resting-state and during the psychomotor vigilance test, as well as task-induced cerebral blood flow changes in a cohort of 38 healthy participants over a full day. The results demonstrated excellent test-retest reliability for absolute cerebral blood flow measurements at rest and during the psychomotor vigilance test throughout the day. However, task-induced cerebral blood flow changes exhibited poor reliability across various brain regions and networks. Furthermore, reliability declined over longer time intervals within the day, particularly during nighttime scans compared to daytime scans. These findings highlight the superior reliability of absolute cerebral blood flow compared to task-induced cerebral blood flow changes and emphasize the importance of controlling time-of-day effects to enhance the reliability and reproducibility of future brain imaging studies.
Asunto(s)
Encéfalo , Circulación Cerebrovascular , Imagen por Resonancia Magnética , Descanso , Humanos , Masculino , Femenino , Adulto , Circulación Cerebrovascular/fisiología , Reproducibilidad de los Resultados , Descanso/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Encéfalo/irrigación sanguínea , Adulto Joven , Imagen por Resonancia Magnética/métodos , Imagen de Perfusión/métodos , Desempeño Psicomotor/fisiología , Ritmo Circadiano/fisiología , Nivel de Alerta/fisiologíaRESUMEN
OBJECTIVE: Delayed cerebral ischemia (DCI) is a potentially reversible adverse event after aneurysmal subarachnoid hemorrhage (aSAH), when early detected and treated. Computer tomography perfusion (CTP) is used to identify the tissue at risk for DCI. In this study, the predictive power of early CTP was compared with that of blood distribution on initial CT for localization of tissue at risk for DCI. METHODS: A consecutive patient cohort with aSAH treated between 2012 and 2020 was retrospectively analyzed. Blood distribution on CT was semi-quantitatively assessed with the Hijdra-score. The vessel territory with the most surrounding blood and the one with perfusion deficits on CTP performed on day 3 after ictus were considered to be at risk for DCI, respectively. RESULTS: A total of 324 patients were included. Delayed infarction occurred in 17% (56/324) of patients. Early perfusion deficits were detected in 82% (46/56) of patients, 85% (39/46) of them developed infarction within the predicted vessel territory at risk. In 46% (25/56) a vessel territory at risk was reliably determined by the blood distribution. For the prediction of DCI, blood amount/distribution was inferior to CTP. Concerning the identification of "tissue at risk" for DCI, a combination of both methods resulted in an increase of sensitivity to 64%, positive predictive value to 58%, and negative predictive value to 92%. CONCLUSIONS: Regarding the DCI-prediction, early CTP was superior to blood amount/distribution, while a consideration of subarachnoid blood distribution may help identify the vessel territories at risk for DCI in patients without early perfusion deficits.
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Isquemia Encefálica , Hemorragia Subaracnoidea , Tomografía Computarizada por Rayos X , Humanos , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/diagnóstico por imagen , Masculino , Femenino , Persona de Mediana Edad , Isquemia Encefálica/etiología , Anciano , Tomografía Computarizada por Rayos X/métodos , Estudios Retrospectivos , Adulto , Circulación Cerebrovascular/fisiología , Imagen de Perfusión/métodosRESUMEN
BACKGROUND: Postoperative pulmonary growth in congenital diaphragmatic hernias (CDH) remains unclear. We investigated postoperative pulmonary vascular growth using serial lung perfusion scintigraphy in patients with CDH. METHODS: Neonates with left CDH who underwent surgery and postoperative lung perfusion scintigraphy at our institution between 2001 and 2020 were included. Patient demographics, clinical courses, and lung scintigraphy data were retrospectively analyzed by reviewing medical records. RESULTS: Twenty-one patients with CDH were included. Of these, 10 underwent serial lung scintigraphy. The ipsilateral perfusion rate and median age on the 1st and serial lung scintigraphy were 32% (34 days) and 33% (3.6 years), respectively. Gestational age at prenatal diagnosis (p = 0.02), alveolar-arterial oxygen difference (A-aDO2) at birth (p = 0.007), and preoperative nitric oxide (NO) use (p = 0.014) significantly correlated with the 1st lung scintigraphy. No other variables, including operative approach, were significantly correlated with the 1st or serial scintigraphy findings. All patients improved lung perfusion with serial studies [Difference: + 7.0 (4.3-13.25) %, p = 0.001, paired t-test]. This improvement was not significantly correlated with preoperative A-aDO2 (p = 0.96), NO use (p = 0.28), or liver up (p = 0.90). The difference was significantly larger in patients who underwent thoracoscopic repair than in those who underwent open abdominal repair [+ 10.6 (5.0-17.1) % vs. + 4.25 (1.2-7.9) %, p = 0.042]. CONCLUSION: Our study indicated a postoperative improvement in ipsilateral lung vascular growth, which is possibly enhanced by a minimally invasive approach, in patients with CDH.
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Hernias Diafragmáticas Congénitas , Pulmón , Humanos , Hernias Diafragmáticas Congénitas/cirugía , Hernias Diafragmáticas Congénitas/diagnóstico por imagen , Estudios Retrospectivos , Femenino , Masculino , Recién Nacido , Pulmón/diagnóstico por imagen , Pulmón/irrigación sanguínea , Periodo Posoperatorio , Imagen de Perfusión/métodos , PreescolarRESUMEN
4D-flow MRI is a promising technique for assessing vessel hemodynamics. However, its utilization is currently limited by the lack of reference values, particularly for pulmonary vessels. In this work, we have analysed flow and velocity in the pulmonary trunk (PT), left and right pulmonary arteries (LPA and RPA, respectively) in Landrace pigs at both rest and stress through the software MEVISFlow. Nine healthy Landrace pigs were acutely instrumented closed-chest and transported to the CMR facility for evaluation. After rest measurements, dobutamine was administered to achieve a 25% increase in heart rate compared to rest. 4D-flow MRI images have been analysed through MEVISFlow by two independent observers. Inter- and intra-observer reproducibility was quantified using intraclass correlation coefficient. A significant difference between rest and stress regarding flow and velocity in all the pulmonary vessels was observed. Mean flow increased 55% in PT, 75% in LPA and 40% in RPA. Mean peak velocity increased 55% in PT, 75% in LPA and 66% in RPA. A good-to-excellent reproducibility was observed in rest and stress for flow measurements in all three arteries. An excellent reproducibility for velocity was found in PT at rest and stress, a good one for LPA and RPA at rest, while poor reproducibility was found at stress. The current study showed that pulmonary flow and velocity assessed through 4D-flow MRI follow the physiological alterations during cardiac cycle and after stress induced by dobutamine. A clinical translation to assess pulmonary diseases with 4D-flow MRI under stress conditions needs investigation.
Asunto(s)
Dobutamina , Valor Predictivo de las Pruebas , Arteria Pulmonar , Circulación Pulmonar , Sus scrofa , Animales , Reproducibilidad de los Resultados , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/fisiopatología , Dobutamina/administración & dosificación , Dobutamina/farmacología , Velocidad del Flujo Sanguíneo , Variaciones Dependientes del Observador , Imagen de Perfusión/métodos , Hemodinámica , Interpretación de Imagen Asistida por Computador , Modelos Animales , Imagen por Resonancia Magnética , Femenino , Angiografía por Resonancia Magnética , Frecuencia CardíacaRESUMEN
PURPOSE: Dynamic chest radiography using X-ray fluoroscopic video analysis has shown potential for the diagnosis of pulmonary embolism (PE), but its diagnostic performance remains uncertain. We aimed to evaluate the diagnostic performance of fluoroscopic video analysis for diagnosing PE. METHODS: A prospective single-center observational study was conducted between October 2020 and January 2022. Fifty consecutive adult patients, comprising definitive PE, pulmonary hypertension (PH), or suspected PH, were enrolled. The study population was classified into 23 PE and 27 non-PE cases by contrast-enhanced computed tomography, lung scintigraphy, right heart catheterization, and pulmonary angiography. Cineradiographic images of 10-second breath-holds were obtained and analyzed using a fluoroscopic video analysis workstation to generate pulmonary circulation images. Two blinded cardiologists qualitatively assessed the presence or absence of perfusion defects on the pulmonary circulation images. The diagnosis obtained from the fluoroscopic analysis was compared with the definitive diagnosis. The primary outcomes included sensitivity, specificity, positive and negative predictive values, and overall accuracy for diagnosing PE. RESULTS: Perfusion defects were observed in 21 of 23 PE patients and 13 of 27 non-PE patients. The diagnostic performance of fluoroscopic video analysis for diagnosing PE showed a sensitivity of 91%, specificity of 52%, positive predictive value of 62%, negative predictive value of 88%, and overall accuracy of 70%. CONCLUSIONS: The high sensitivity of the fluoroscopic video analysis suggests its potential usefulness in ruling out PE without the need for contrast media or radionuclide; however, its specificity and overall accuracy remain limited.
Asunto(s)
Valor Predictivo de las Pruebas , Embolia Pulmonar , Humanos , Embolia Pulmonar/diagnóstico por imagen , Estudios Prospectivos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Fluoroscopía , Reproducibilidad de los Resultados , Circulación Pulmonar , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/fisiopatología , Cinerradiografía , Grabación en Video , Adulto , Imagen de Perfusión/métodos , Hipertensión Pulmonar/diagnóstico por imagen , Hipertensión Pulmonar/fisiopatología , Interpretación de Imagen Radiográfica Asistida por ComputadorRESUMEN
OBJECTIVE: To quantitatively investigate the longitudinal computed tomography perfusion (CTP) imaging in meningiomas preoperatively embolized using microcatheters. METHODS: This retrospective monocentric study included 27 patients with symptomatic supratentorial meningiomas. Quantitative computed tomography perfusion (CTP) images before and postembolization were evaluated and correlated with angiographic, immunohistochemical, and clinical data. RESULTS: The mean age of the patients was 45 ± 18 years, with a female-to-male ratio of 1.45:1. After embolization, both the embolized (Eb) and unembolized (UEb) regions showed hypoperfusion. A steady state was achieved on days 4-6 postembolization, during which differences in regional cerebral blood volume (rCBV) (Eb 0.5 ± 0.3 ml/100 mg, UEb 3.3 ± 1.4 ml/100 mg; P < 0.05), and mean transit time (MTT) (Eb 3.5 ± 1.8 s, UEb 3.1 ± 0.4 s) were observed. The cerebral blood flow (rCBF) and time to the peak (TTP) exhibited opposite patterns between Eb and UEb. A steady state was reached in rCBF (Eb 1.7 ± 1.2 ml/100 g/min, UEb 30 ± 5.4 ml/100 g/min; P < 0.01), and TTP (Eb 5 ± 4.8 s, UEb 1.8 ± 1.5 s; P < 0.01) within 4 to 6 days. Estimated blood loss (EBL) showed significant association with the surgical time interval among the 3 groups (P < 0.05). Tissue necrosis predominated over 7 days postembolization, indicating a correlation with the devascularization process. The overall incidence of postembolized headache, seizures, extremity weakness/paralysis, and postoperational headache was 11.1%, 7.4%, 3.7%; and 7.4%, respectively. All symptoms resolved by the last follow-up (3 months). CONCLUSION: Preoperative embolization of meningiomas using N-butyl cyanoacrylate effectively induced significant and sustained tissue transformation and decreased estimated blood loss (EBL) over 7 days. Hemodynamic fluctuations tended to stabilize within 4 to 6 days.
Asunto(s)
Circulación Cerebrovascular , Embolización Terapéutica , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/cirugía , Meningioma/diagnóstico por imagen , Femenino , Masculino , Persona de Mediana Edad , Embolización Terapéutica/métodos , Neoplasias Meníngeas/cirugía , Neoplasias Meníngeas/diagnóstico por imagen , Adulto , Estudios Retrospectivos , Circulación Cerebrovascular/fisiología , Anciano , Resultado del Tratamiento , Procedimientos Endovasculares/métodos , Cuidados Preoperatorios/métodos , Imagen de Perfusión/métodos , Estudios Longitudinales , Tempo Operativo , Tomografía Computarizada por Rayos XRESUMEN
INTRODUCTION: Dynamic susceptibility contrast (DSC) perfusion weighted (PW)-MRI can aid in differentiating treatment related abnormalities (TRA) from tumor progression (TP) in post-treatment glioma patients. Common methods, like the 'hot spot', or visual approach suffer from oversimplification and subjectivity. Using perfusion of the complete lesion potentially offers an objective and accurate alternative. This study aims to compare the diagnostic value and assess the subjectivity of these techniques. METHODS: 50 Glioma patients with enhancing lesions post-surgery and chemo-radiotherapy were retrospectively included. Outcome was determined by clinical/radiological follow-up or biopsy. Imaging analysis used the 'hot spot', volume of interest (VOI) and visual approach. Diagnostic accuracy was compared using receiving operator characteristics (ROC) curves for the VOI and 'hot spot' approach, visual assessment was analysed with contingency tables. Inter-operator agreement was determined with Cohens kappa and intra-class coefficient (ICC). RESULTS: 29 Patients suffered from TP, 21 had TRA. The visual assessment showed poor to substantial inter-operator agreement (κ = -0.72 - 0.68). Reliability of the 'hot spot' placement was excellent (ICC = 0.89), while reference placement was variable (ICC = 0.54). The area under the ROC (AUROC) of the mean- and maximum relative cerebral blood volume (rCBV) (VOI-analysis) were 0.82 and 0.72, while the rCBV-ratio ('hot spot' analysis) was 0.69. The VOI-analysis had a more balanced sensitivity and specificity compared to visual assessment. CONCLUSIONS: VOI analysis of DSC PW-MRI data holds greater diagnostic accuracy in single-moment differentiation of TP and TRA than 'hot spot' or visual analysis. This study underlines the subjectivity of visual placement and assessment.
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Neoplasias Encefálicas , Glioma , Humanos , Masculino , Glioma/diagnóstico por imagen , Glioma/terapia , Femenino , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/terapia , Persona de Mediana Edad , Estudios Retrospectivos , Adulto , Anciano , Medios de Contraste , Interpretación de Imagen Asistida por Computador/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Imagen de Perfusión/métodos , Progresión de la Enfermedad , Angiografía por Resonancia Magnética/métodosRESUMEN
PURPOSE: To improve the spatial resolution and repeatability of a non-contrast MRI technique for simultaneous time resolved 3D angiography and perfusion imaging by developing an efficient 3D cone trajectory design. METHODS: A novel parameterized 3D cone trajectory design incorporating the 3D golden angle was integrated into 4D combined angiography and perfusion using radial imaging and arterial spin labeling (CAPRIA) to achieve higher spatial resolution and sampling efficiency for both dynamic angiography and perfusion imaging with flexible spatiotemporal resolution. Numerical simulations and physical phantom scanning were used to optimize the cone design. Eight healthy volunteers were scanned to compare the original radial trajectory in 4D CAPRIA with our newly designed cone trajectory. A locally low rank reconstruction method was used to leverage the complementary k-space sampling across time. RESULTS: The improved sampling in the periphery of k-space obtained with the optimized 3D cone trajectory resulted in improved spatial resolution compared with the radial trajectory in phantom scans. Improved vessel sharpness and perfusion visualization were also achieved in vivo. Less dephasing was observed in the angiograms because of the short TE of our cone trajectory and the improved k-space sampling efficiency also resulted in higher repeatability compared to the original radial approach. CONCLUSION: The proposed 3D cone trajectory combined with 3D golden angle ordering resulted in improved spatial resolution and image quality for both angiography and perfusion imaging and could potentially benefit other applications that require an efficient sampling scheme with flexible spatial and temporal resolution.
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Imagenología Tridimensional , Angiografía por Resonancia Magnética , Fantasmas de Imagen , Marcadores de Spin , Humanos , Imagenología Tridimensional/métodos , Angiografía por Resonancia Magnética/métodos , Reproducibilidad de los Resultados , Adulto , Masculino , Algoritmos , Femenino , Imagen de Perfusión/métodos , Voluntarios Sanos , Procesamiento de Imagen Asistido por Computador/métodos , Simulación por ComputadorRESUMEN
Oxygen content is crucial for the functioning of human body organs, as it plays a vital role in cellular respiration, which generates energy necessary for life-sustaining functions. The absence of adequate oxygen leads to cellular dysfunction and eventual organismal death due to energy deprivation. In this study, we designed a rapid, non-invasive, and non-contact custom hyperspectral imaging system to assess blood perfusion in arteries, capillaries, and veins across various human organs, including the arm, eye, and leg. The system recorded cube images consisting of multispectral image ranges, capturing spectral information in both the visible and infrared spectra. Segmentation of the visible spectrum (400 to 700 nm) and the infrared spectrum (700 to 1000 nm) facilitated the mapping of blood oxygen levels in the investigated samples. The estimated oxygen levels were calculated using the custom hyperspectral imaging system and associated algorithm, with validation and calibration performed against the gold standard pulse oximeter. Our results demonstrate that the custom hyperspectral imaging system accurately mapped blood perfusion and oxygen levels in organs, showing strong agreement with pulse oximeter measurements. This study underscores the utility of custom hyperspectral imaging in non-invasively assessing blood oxygenation and perfusion in human organs, offering a promising avenue for clinical diagnostics and monitoring of vascular health.
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Imágenes Hiperespectrales , Oximetría , Oxígeno , Flujo Sanguíneo Regional , Humanos , Oxígeno/sangre , Oximetría/métodos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Algoritmos , Biomarcadores/sangre , Imagen de Perfusión/métodos , MasculinoRESUMEN
BACKGROUND: Stroke AI platforms assess infarcted core and potentially salvageable tissue (penumbra) to identify patients suitable for mechanical thrombectomy. Few studies have compared outputs of these platforms, and none have been multicenter or considered NIHSS or scanner/protocol differences. Our objective was to compare volume estimates and thrombectomy eligibility from two widely used CT perfusion (CTP) packages, Viz.ai and RAPID.AI, in a large multicenter cohort. METHODS: We analyzed CTP data of acute stroke patients with large vessel occlusion (LVO) from four institutions. Core and penumbra volumes were estimated by each software and DEFUSE-3 thrombectomy eligibility assessed. Results between software packages were compared and categorized by NIHSS score, scanner manufacturer/model, and institution. RESULTS: Primary analysis of 362 cases found statistically significant differences in both software's volume estimations, with subgroup analysis showing these differences were driven by results from a single scanner model, the Canon Aquilion One. Viz.ai provided larger estimates with mean differences of 8cc and 18cc for core and penumbra, respectively (p<0.001). NIHSS subgroup analysis also showed systematically larger Viz.ai volumes (p<0.001). Despite volume differences, a significant difference in thrombectomy eligibility was not found. Additional subgroup analysis showed significant differences in penumbra volume for the Phillips Ingenuity scanner, and thrombectomy eligibility for the Canon Aquilion One scanner at one center (7 % increased eligibility with Viz.ai, p=0.03). CONCLUSIONS: Despite systematic differences in core and penumbra volume estimates between Viz.ai and RAPID.AI, DEFUSE-3 eligibility was not statistically different in primary or NIHSS subgroup analysis. A DEFUSE-3 eligibility difference, however, was seen on one scanner at one institution, suggesting scanner model and local CTP protocols can influence performance and cause discrepancies in thrombectomy eligibility. We thus recommend centers discuss optimal scanning protocols with software vendors and scanner manufacturers to maximize CTP accuracy.
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Circulación Cerebrovascular , Selección de Paciente , Imagen de Perfusión , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Programas Informáticos , Trombectomía , Humanos , Trombectomía/efectos adversos , Imagen de Perfusión/métodos , Femenino , Masculino , Anciano , Reproducibilidad de los Resultados , Persona de Mediana Edad , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/cirugía , Accidente Cerebrovascular Isquémico/fisiopatología , Accidente Cerebrovascular Isquémico/diagnóstico , Estudios Retrospectivos , Toma de Decisiones Clínicas , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/cirugía , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/diagnóstico , Tomografía Computarizada por Rayos X , Angiografía por Tomografía Computarizada , Anciano de 80 o más AñosRESUMEN
BACKGROUND: Delayed cerebral ischemia and vasospasm are the most common causes of late morbidity following aneurysmal SAH, but their diagnosis remains challenging. PURPOSE: This systematic review and meta-analysis investigated the diagnostic performance of CTP for detection of delayed cerebral ischemia and vasospasm in the setting of aneurysmal SAH. DATA SOURCES: Studies evaluating the diagnostic performance of CTP in the setting of aneurysmal SAH were searched on the Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Cochrane Clinical Answers, Cochrane Methodology Register, Ovid MEDLINE, EMBASE, American College of Physicians Journal Club, Database of Abstracts of Reviews of Effects, Health Technology Assessment, National Health Service Economic Evaluation Database, PubMed, and Google Scholar from their inception to September 2023. STUDY SELECTION: Thirty studies were included, encompassing 1786 patients with aneurysmal SAH and 2302 CTP studies. Studies were included if they compared the diagnostic accuracy of CTP with a reference standard (clinical or radiologic delayed cerebral ischemia, angiographic spasm) for the detection of delayed cerebral ischemia or vasospasm in patients with aneurysmal SAH. The primary outcome was accuracy for the detection of delayed cerebral ischemia or vasospasm. DATA ANALYSIS: Bivariate random effects models were used to pool outcomes for sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio. Subgroup analyses for individual CTP parameters and early-versus-late study timing were performed. Bias and applicability were assessed using the modified QUADAS-2 tool. DATA SYNTHESIS: For assessment of delayed cerebral ischemia, CTP demonstrated a pooled sensitivity of 82.1% (95% CI, 74.5%-87.8%), specificity of 79.6% (95% CI, 73.0%-84.9%), positive likelihood ratio of 4.01 (95% CI, 2.94-5.47), and negative likelihood ratio of 0.23 (95% CI, 0.12-0.33). For assessment of vasospasm, CTP showed a pooled sensitivity of 85.6% (95% CI, 74.2%-92.5%), specificity of 87.9% (95% CI, 79.2%-93.3%), positive likelihood ratio of 7.10 (95% CI, 3.87-13.04), and negative likelihood ratio of 0.16 (95% CI, 0.09-0.31). LIMITATIONS: QUADAS-2 assessment identified 12 articles with low risk, 11 with moderate risk, and 7 with a high risk of bias. CONCLUSIONS: For delayed cerebral ischemia, CTP had a sensitivity of >80%, specificity of >75%, and a low negative likelihood ratio of 0.23. CTP had better performance for the detection of vasospasm, with sensitivity and specificity of >85% and a low negative likelihood ratio of 0.16. Although the accuracy offers the potential for CTP to be used in limited clinical contexts, standardization of CTP techniques and high-quality randomized trials evaluating its impact are required.
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Isquemia Encefálica , Hemorragia Subaracnoidea , Vasoespasmo Intracraneal , Humanos , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/etiología , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/complicaciones , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/complicaciones , Sensibilidad y Especificidad , Angiografía Cerebral/métodos , Tomografía Computarizada por Rayos X , Imagen de Perfusión/métodosRESUMEN
BACKGROUND: Endovascular treatment (EVT) is effective for large vessel occlusion (LVO) stroke with smaller volumes of CT perfusion (CTP)-defined core. However, the influence of perfusion imaging during thrombectomy on the functional outcomes of patients with large ischemic core (LIC) stroke at both early and late time windows is uncertain in real-world practice. METHOD: A retrospective analysis was performed on 99 patients who underwent computed tomography angiography (CTA) and CT perfusion (CTP)-Rapid Processing of Perfusion and Diffusion (RAPID) before EVT and had a baseline ischemic core ≥ 50 mL and/or Alberta Stroke Program Early CT Score (ASPECTS) score of 0-5. The primary outcome was the three-month modified Rankin Scale (mRS) score. Data were analyzed by binary logistic regression and receiver operating characteristic (ROC) curves. RESULTS: A fair outcome (mRS, 0-3) was found in 34 of the 99 patients while 65 had a poor prognosis (mRS, 4-6). The multivariate logistic regression analysis showed that onset-to-reperfusion (OTR) time (odds ratio [OR], 1.004; 95% confidence interval [CI], 1.001-1.007; p = 0.008), ischemic core (OR, 1.066; 95% CI, 1.024-1.111; p = 0.008), and the hypoperfusion intensity ratio (HIR) (OR, 70.898; 95% CI, 1.130-4450.152; p = 0.044) were independent predictors of outcome. The combined results of ischemic core, HIR, and OTR time showed good performance with an area under the ROC curve (AUC) of 0.937, significantly higher than the individual variables (p < 0.05) using DeLong's test. CONCLUSIONS: Higher HIR and longer OTR time in large core stroke patients were independently associated with unfavorable three-month outcomes after EVT.
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Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Trombectomía , Humanos , Masculino , Femenino , Anciano , Procedimientos Endovasculares/métodos , Accidente Cerebrovascular Isquémico/cirugía , Persona de Mediana Edad , Resultado del Tratamiento , Estudios Retrospectivos , Trombectomía/métodos , Anciano de 80 o más Años , Reperfusión/métodos , Isquemia Encefálica/cirugía , Accidente Cerebrovascular/cirugía , Imagen de Perfusión , Angiografía por Tomografía ComputarizadaRESUMEN
OBJECTIVE: Alzheimer's disease, an irreversible neurological condition, demands timely diagnosis for effective clinical intervention. This study employs radiomics analysis to assess image features in default mode network cerebral perfusion imaging among individuals with cognitive impairment. METHODS: A radiomics analysis of cerebral perfusion imaging was conducted on 117 patients with cognitive impairment. They were divided into training and validation sets in a 7:3 ratio. Least Absolute Shrinkage and Selection Operator (LASSO) and Random Forest were employed to select and model image features, followed by logistic regression analysis of LASSO and Random Forest results. Diagnostic performance was assessed by calculating the area under the curve (AUC). RESULTS: In the training set, LASSO achieved AUC of 0.978, Random Forest had an AUC of 0.933. In the validation set, LASSO had AUC of 0.859, Random Forest had AUC of 0.986. By conducting Logistic Regression analysis in combination with LASSO and Random Forest, we identified a total of five radiomics features, with four related to morphology and one to textural features, originating from the medial prefrontal cortex and middle temporal gyrus. In the training set, Logistic Regression achieved AUC of 0.911, while in the validation set, it attained AUC of 0.925. CONCLUSION: The medial prefrontal cortex and middle temporal gyrus are the two brain regions within the default mode network that hold the highest significance for Alzheimer's disease diagnosis. Radiomics analysis contributes to the clinical assessment of Alzheimer's disease by delving into image data to extract deeper layers of information.