Although there are unified criteria for the clinical diagnosis and grading of neonatal hypoxic-ischemic encephalopathy (HIE), clinical features and neuropathological patterns vary considerably among the neonates with HIE due to birth asphyxia in the same classification. The patterns and progression of brain injury in HIE, which is closely associated with long-term neurodevelopment outcomes, can be well shown on magnetic resonance imaging (MRI), but different sequences may lead to different MRI findings at the same time. It is suggested that diffusion-weighted imaging sequence be selected at 2-4 days after birth, and the conventional MRI sequence at 4-8 days. The major patterns of brain injury in HIE on MRI are as follows: injury of the thalamus and basal ganglia and posterior limbs of the internal capsules; watershed injury involving the cortical and subcortical white matter; focal or multifocal minimal white matter injury; extensive whole brain injury. Severe acute birth asphyxia often leads to deep grey matter injury (thalamus and basal ganglia), and the brain stem may also be involved; the pyramidal tract is the most susceptible white matter fiber tract; repetitive or intermittent hypoxic-ischemic insults, with inflammation or hypoglycemia, usually cause injuries in the watershed area and deep white matter. It is worth noting that sometimes the pattern of brain injury among those described above cannot be determined exactly, but rather a predominant one is identified; not all cases of HIE have characteristic MRI findings.
Brain ; diagnostic imaging ; Brain Injuries ; classification ; diagnostic imaging ; Diffusion Magnetic Resonance Imaging ; methods ; Humans ; Hypoxia-Ischemia, Brain ; diagnostic imaging ; Infant, Newborn ; Magnetic Resonance Imaging ; methods

Clinically, non-contrastive computed tomography (NCCT) is used to quickly diagnose the type and area of ​​stroke, and the Alberta stroke program early computer tomography score (ASPECTS) is used to guide the next treatment. However, in the early stage of acute ischemic stroke (AIS), it's difficult to distinguish the mild cerebral infarction on NCCT with the naked eye, and there is no obvious boundary between brain regions, which makes clinical ASPECTS difficult to conduct. The method based on machine learning and deep learning can help physicians quickly and accurately identify cerebral infarction areas, segment brain areas, and operate ASPECTS quantitative scoring, which is of great significance for improving the inconsistency in clinical ASPECTS. This article describes current challenges in the field of AIS ASPECTS, and then summarizes the application of computer-aided technology in ASPECTS from two aspects including machine learning and deep learning. Finally, this article summarizes and prospects the research direction of AIS-assisted assessment, and proposes that the computer-aided system based on multi-modal images is of great value to improve the comprehensiveness and accuracy of AIS assessment, which has the potential to open up a new research field for AIS-assisted assessment.
Alberta ; Brain Ischemia/diagnostic imaging* ; Humans ; Ischemic Stroke ; Stroke/diagnostic imaging* ; Tomography, X-Ray Computed

Brain Ischemia ; Cardiomyopathy, Hypertrophic/diagnostic imaging* ; Hemorrhagic Stroke ; Humans ; Moyamoya Disease/diagnostic imaging* ; Stroke/etiology*

OBJECTIVETo investigate the role of cerebral computed tomography (CT) in the evaluation of the severity of brain injury following hypoxia in neonates.

METHODSA total of 114 full-term newborns who had perinatal hypoxia, including 25 cases of hypoxic-ischemic encephalopathy (HIE), 36 cases of neonatal asphyxia and 53 cases of simple intrauterine fetal distress, were enrolled in this study. Twenty normal newborns served as the Control group. All had cerebral CT scan at 2-7 days of age. Neonatal behavior neurological assessment (NBNA) was performed at 5 days of age.

RESULTSThe average NBNA scores were significantly lower and the abnormality rate of NBNA was significantly higher in the HIE group than in the other three groups (P < 0.05). The Asphyxia and the Distress groups had also lower NBNA scores and higher abnormality rate of NBNA than the Control group (P < 0.05). Twenty-two patients were found to have cerebral CT abnormality in the HIE group, but there was only 1 case in the Control group (P < 0.01). The abnormality rate of cerebral CT in the Asphyxia and the Distress groups was not statistically different from that of the Control group. Twenty-five cases of HIE were divided into mild (n=15), medium (n=6) and severe (n=4) by clinical grading but were divided into normal (n=3), mild (n=10), medium (n=7) and severe (n=5) by CT grading. CT and clinical grading on HIE was not consistent. The sensitivity of CT in the diagnosis of mild, moderate and severe HIE was 47%, 33% and 50% respectively, the specificity was 70%, 74% and 86% respectively and the accuracy was 48%, 64% and 80% respectively.

CONCLUSIONSCT evaluation on mild brain injury induced by asphyxia or intrauterine fetal distress is not of any value and the role of CT evaluation on the HIE grade is uncertain and doubtful.

Asphyxia Neonatorum ; diagnostic imaging ; Brain ; diagnostic imaging ; Female ; Fetal Distress ; diagnostic imaging ; Humans ; Hypoxia-Ischemia, Brain ; diagnostic imaging ; Infant, Newborn ; Male ; Neurologic Examination ; Tomography, X-Ray Computed

OBJECTIVETo determine the distribution of aortic arch and intra/extracranial cerebral arterial atherosclerosis in Chinese patients who had suffered acute ischemic strokes.

METHODSEighty-nine patients with acute ischemic strokes were included in this study. Transesophageal echocardiography (TEE) was used to evaluate potential sources of embolisms in the aortic arch and in the heart; duplex ultrasound was used for the carotid artery; and intracranial Doppler (TCD) imaging was used for the middle cerebral artery (MCA), anterior cerebral artery (ACA), posterior cerebral artery (PCA), and basilar artery (BA). An atherosclerotic lesion in the aortic arch was defined as normal (0); mild plaque (1); moderate plaque (2); and protruding plaque or mobile plaque (3). A lesion in the carotid artery was considered a plaque if the maximal carotid plaque thickness was 1.2 mm. TCD results were deemed abnormal if flow velocity was either greater or lower than normal, and, in the case of the MCA, if an asymmetry index above 21% was measured.

RESULTSOf the 89 patients, 52 (58.43%) patients showed evidence of aortic arch atherosclerosis (AAA), including 11 (12.36%) patients graded mild, 18 (20.22%) patients graded moderate, and 23 (25.84%) patients graded severe. Of the 23 patients with severe AAA, AAA was determined to be an important potential embolic source in 14 patients. Forty-nine (50.56%) patients had carotid arterial plaques (CAPs). The incidence of carotid plaques was higher among patients with AAA than among patients without AAA (71.15% vs 21.62%, OR = 3.291, 95% CI = 1.740 - 6.225, P < 0.001). TCD abnormalities affecting the MCA were found in 54 (60.67%) patients. Differences in incidence of TCD abnormalities between patients with AAA and without AAA (69.23% vs 48.65%) were not significant (OR = 1.423, 95% CI = 0.976 - 2.076, P = 0.05). There was a higher incidence of AAA in older, male patients with a history of diabetes and smoking.

CONCLUSIONSAAA is an important potential source of cerebral embolic strokes. The presence of carotid arterial plaques correlates with AAA incidence. Most of carotid artery lesion were plaques other than severe stenosis, it may be the character of carotid atherosclerosis of stroke patients. It appears that atherosclerosis does not mainly occur in the intracranial arteries in stroke patients as thought before. Aged, male, diabetes, and smoking are important risk factors to the AAA.

Acute Disease ; Aged ; Aorta, Thoracic ; diagnostic imaging ; Aortic Diseases ; diagnostic imaging ; Arteriosclerosis ; diagnostic imaging ; Brain Ischemia ; diagnostic imaging ; Female ; Humans ; Intracranial Arteriosclerosis ; diagnostic imaging ; Intracranial Embolism ; diagnostic imaging ; Male ; Middle Aged ; Stroke ; diagnostic imaging ; Ultrasonography

OBJECTIVES: To explore a new method for electroencephalography (EEG) background analysis in neonates with hypoxic-ischemic encephalopathy (HIE) and its relationship with clinical grading and head magnetic resonance imaging (MRI) grading. METHODS: A retrospective analysis was performed for the video electroencephalography (vEEG) and amplitude-integrated electroencephalography (aEEG) monitoring data within 24 hours after birth of neonates diagnosed with HIE from January 2016 to August 2022. All items of EEG background analysis were enrolled into an assessment system and were scored according to severity to obtain the total EEG score. The correlations of total EEG score with total MRI score and total Sarnat score (TSS, used to evaluate clinical gradings) were analyzed by Spearman correlation analysis. The total EEG score was compared among the neonates with different clinical gradings and among the neonates with different head MRI gradings. The receiver operating characteristic (ROC) curve and the area under thecurve (AUC) were used to evaluate the value of total EEG score in diagnosing moderate/severe head MRI abnormalities and clinical moderate/severe HIE, which was then compared with the aEEG grading method. RESULTS: A total of 50 neonates with HIE were included. The total EEG score was positively correlated with the total head MRI score and TSS (r_s=0.840 and 0.611 respectively, P<0.001). There were significant differences in the total EEG score between different clinical grading groups and different head MRI grading groups (P<0.05). The total EEG score and the aEEG grading method had an AUC of 0.936 and 0.617 respectively in judging moderate/severe head MRI abnormalities (P<0.01) and an AUC of 0.887 and 0.796 respectively in judging clinical moderate/severe HIE (P>0.05). The total EEG scores of ≤6 points, 7-13 points, and ≥14 points were defined as mild, moderate, and severe EEG abnormalities respectively, which had the best consistency with clinical grading and head MRI grading (P<0.05). CONCLUSIONS The new EEG background scoring method can quantitatively reflect the severity of brain injury and can be used for the judgment of brain function in neonates with HIE.
Infant, Newborn ; Humans ; Hypoxia-Ischemia, Brain/diagnostic imaging* ; Retrospective Studies ; Brain Injuries ; Electroencephalography ; ROC Curve

The present study aimed to improve the processing of data acquired from laser speckle contrast imaging (LSCI) to provide a standardization method to explore changes in regional cerebral blood flow (rCBF) and to determine the correlations among rCBF, cerebral ischemic lesion volume and microvascular density over time in a focal ischemic region. C57BL/6J mice were subjected to focal photothrombotic (PT) ischemia. rCBF was measured using LSCI at different time points before and after PT ischemia through an intact skull. Standardized rCBF (SrCBF), defined as the ratio of rCBF measured in the ipsilateral region of interest (ROI) to that in the corresponding contralateral region, was calculated to evaluate potential changes. In addition, the volume of the ischemic lesion and the microvascular density were determined using Nissl staining and immunofluorescence, respectively. The relationships among the ischemic lesion volume, microvascular density and SrCBF were analyzed over time. The results showed that the cortical rCBF measured using LSCI following PT ischemia in the C57BL/6J mice gradually increased. Changes in the cerebral ischemic lesion volume were negatively correlated with SrCBF in the ischemic region. Changes in the microvascular density were similar to those observed in SrCBF. Our findings indicate that LSCI is a practical technique for observing changes in murine cortical rCBF without skull opening and for analyzing the relationships among the ischemic lesion volume, microvascular density and SrCBF following focal cerebral ischemia. Preliminary results also suggest that the use of LSCI to observe the formation of collateral circulation is feasible.
Animals ; Brain Ischemia ; diagnostic imaging ; etiology ; Cerebrovascular Circulation ; Diagnostic Imaging ; methods ; Intracranial Thrombosis ; diagnostic imaging ; etiology ; Laser-Doppler Flowmetry ; methods ; Light ; adverse effects ; Male ; Mice ; Mice, Inbred C57BL

OBJECTIVETo evaluate the hemodynamic changes in the central branches of the middle cerebral artery in different stages of neonatal hypoxic-ischemic encephalopathy (HIE) and provide new evidence for clinical diagnosis of HIE.

METHODSFrom March, 2013 to July, 2013, a total of 136 newborn infants were diagnosed to have HIE in our center. We performed two-dimensional ultrasonography and color Doppler ultrasound for assessments of systolic velocity (Vs) and resistant index (RI) of the central branches of the middle cerebral artery. The data were compared with the results of a control group consisting of 251 normal full-term infants.

RESULTSInfants with mild HIE showed hyperechoic changes in the white matter around the ventricle, while in moderate and severe HIE, such hyperechoic changes were diffuse in both hemispheres with unclear echoes of the brain structures. Pulse Doppler assessments of hemodynamics of the central branches of the middle cerebral artery demonstrated a significant decrease in Vs and an increase in RI regardless of HIE severity (P<0.05). In addition, Vs and RI values in mild HIE infants differed significantly (P<0.05) from those in infants with moderate and severe HIE, who had comparable Vs and RI values (P>0.05).

CONCLUSIONTranscranial ultrasonography may provide dynamic information on cerebral blood flow in neonates and hemodynamic parameters of the central branches of the middle cerebral artery are valuable for clinical diagnosis and early intervention of HIE.

Brain ; blood supply ; Cerebrovascular Circulation ; Hemodynamics ; Humans ; Hypoxia-Ischemia, Brain ; diagnostic imaging ; Infant ; Infant, Newborn ; Middle Cerebral Artery ; diagnostic imaging ; Ultrasonography

OBJECTIVETo evaluate the changes of cerebral blood flow (CBF) with real-time contrast-enhanced ultrasound (CEU) in a canine model of acute cerebral ischemia.

METHODSCerebral perfusion was assessed in 6 dogs subjected to craniotomy with CEU at the time of 0, 30, 60, 90 and 120 min after occlusion of the left common carotid artery (LCCA). The microvascular volume (A) and blood flow velocity (beta) in the brain were measured from the time-versus-acoustic intensity plots, and the value of Axbeta were calculated. 99mTc-ECD brain single photon emission computed tomography (SPECT) was performed on the day before the experiment and at 120 min after LCCA occlusion. The radioactive counts on both sides of the cerebral cortex were calculated.

RESULTSA significant correlation was found between Axbeta from CEU and volume of the blood flow of the CCA from Doppler flowmetry. A, beta and Axbeta values varied significantly between the different time points (P>0.001). The ipsilateral hemisphere showed a low-perfusion state while the contralateral hemisphere showed a high-perfusion state immediately after the occlusion.

CONCLUSIONSThe changes of beta is the main regulation mechanism during acute cerebral ischemia in dogs.

Animals ; Blood Flow Velocity ; Brain ; blood supply ; Brain Ischemia ; diagnostic imaging ; Cerebrovascular Circulation ; Dogs ; Male ; Regional Blood Flow ; Ultrasonography

OBJECTIVETo investigate the current status of the application of H-magnetic resonance spectroscopy (H-MRS) in neonates with hypoxic-ischemic encephalopathy (HIE), and to describe the trend of research in the field.

METHODSPubMed, EMBASE, and Web of Science were searched for English articles published up to January 10, 2018, with the combination of key words and MeSH terms. The articles were screened according to inclusion and exclusion criteria. Excel 2016, Bicomb 2.0, and VOSviewer1.6.6 were used to analyze the key words, to perform a cluster analysis of hot words, and to plot the knowledge map.

RESULTSA total of 66 articles were included, and 27 high-frequency key words were extracted. The results showed that H-MRS was mainly used in four directions of the clinical practice and scientific research on HIE. In clinical practice, H-MRS attracted wide attention as a clinical examination for HIE and a tool for prognostic evaluation; in scientific research, H-MRS was used in animal experiments and studies associated with mild hypothermia therapy.

CONCLUSIONSAs an auxiliary means of magnetic resonance imaging, H-MRS plays an important role in investigating the pathogenesis of neonatal HIE, improving existing therapies, and evaluating the prognosis of neonates with HIE.

Female ; Humans ; Hypoxia-Ischemia, Brain ; diagnosis ; diagnostic imaging ; Infant, Newborn ; Infant, Newborn, Diseases ; diagnosis ; diagnostic imaging ; Magnetic Resonance Imaging ; methods ; Male