Weakly supervised multitask learning models to identify symptom onset time of unclear-onset intracerebral hemorrhage.

BACKGROUND: Approximately one-third of spontaneous intracerebral hemorrhage patients did not know the onset time and were excluded from studies about time-dependent treatments for hyperacute spontaneous intracerebral hemorrhage. AIMS: To help clinicians explore the benefit of time-dependent treatments for unclear-onset patients, we presented artificial intelligence models to identify onset time using non-contrast computed tomography (NCCT) based on weakly supervised multitask learning (WS-MTL) structure. METHODS: The patients with reliable symptom onset time (strong label) or repeat CT (weak label) were included and split into training set and test set (internal and external). The WS-MTL structure utilized strong and weak labels simultaneously to improve performance. The models included three binary classification models for classifying whether NCCT acquired within 6, 8 or 12 h for different treatments measured by area under curve, and a regression model for determining the exact onset time measured by mean absolute error. The generalizability of models was also explored in comprehensive analysis. RESULTS: A total of 4004 patients with 10,780 NCCT scans were included. The performance of WS-MTL classification model showed high accuracy, and that of regression model was satisfactory in ≤6 h subgroup. In comprehensive analysis, the WS-MTL showed better performance for larger hematomas and thinner scans. And the performance improved effectively as training amounts increasing and could be improved steadily through retraining. CONCLUSIONS: The WS-MTL models showed good performance and generalizability. Considering the large number of unclear-onset spontaneous intracerebral hemorrhage patients, it may be worth to integrate the WS-MTL model into clinical practice to identify the onset time.

Pulmonary complications and respiratory management in neurocritical care: a narrative review / 中华医学杂志(英文版)

Neurocritical care (NCC) is not only generally guided by principles of general intensive care, but also directed by specific goals and methods. This review summarizes the common pulmonary diseases and pathophysiology affecting NCC patients and the progress made in strategies of respiratory support in NCC. This review highlights the possible interactions and pathways that have been revealed between neurological injuries and respiratory diseases, including the catecholamine pathway, systemic inflammatory reactions, adrenergic hypersensitivity, and dopaminergic signaling. Pulmonary complications of neurocritical patients include pneumonia, neurological pulmonary edema, and respiratory distress. Specific aspects of respiratory management include prioritizing the protection of the brain, and the goal of respiratory management is to avoid inappropriate blood gas composition levels and intracranial hypertension. Compared with the traditional mode of protective mechanical ventilation with low tidal volume (Vt), high positive end-expiratory pressure (PEEP), and recruitment maneuvers, low PEEP might yield a potential benefit in closing and protecting the lung tissue. Multimodal neuromonitoring can ensure the safety of respiratory maneuvers in clinical and scientific practice. Future studies are required to develop guidelines for respiratory management in NCC.

The Patterns of Morphological Change During Intracerebral Hemorrhage Expansion: A Multicenter Retrospective Cohort Study.

Objectives: Hemorrhage expansion (HE) is a common and serious condition in patients with intracerebral hemorrhage (ICH). In contrast to the volume changes, little is known about the morphological changes that occur during HE. We developed a novel method to explore the patterns of morphological change and investigate the clinical significance of this change in ICH patients. Methods: The morphological changes in the hematomas of ICH patients with available paired non-contrast CT data were described in quantitative terms, including the diameters of each hematoma in three dimensions, the longitudinal axis type, the surface regularity (SR) index, the length and direction changes of the diameters, and the distance and direction of movement of the center of the hematoma. The patterns were explored by descriptive analysis and difference analysis in subgroups. We also established a prognostic nomogram model for poor outcomes in ICH patients using both morphological changes and clinical parameters. Results: A total of 1,094 eligible patients from four medical centers met the inclusion criteria. In 266 (24.3%) cases, the hematomas enlarged; the median absolute increase in volume was 14.0 [interquartile range (IQR), 17.9] mL. The initial hematomas tended to have a more irregular shape, reflected by a larger surface regularity index, than the developed hematomas. In subtentorial and deep supratentorial hematomas, the center moved in the direction of gravity. The distance of center movement and the length changes of the diameters were small, with median values of less than 4 mm. The most common longitudinal axis type was anterior-posterior (64.7%), and the axis type did not change between initial and repeat imaging in most patients (95.2%). A prognostic nomogram model including lateral expansion, a parameter of morphological change, showed good performance in predicting poor clinical outcomes in ICH patients. Conclusions: The present study provides a morphological perspective on HE using a novel automatic approach. We identified certain patterns of morphological change in HE, and we believe that some morphological change parameters could help physicians predict the prognosis of ICH patients.

Exosome extracted from hAMSCspromotes neurological function recovery after traumatic brain injury in rats / 基础医学与临床

Objective To investigate the therapeutic effect of exosomes extracted from human adipose-derived mesenchymal stem cells(hAMSCs) on traumatic brain injury (TBI) and its possible mechanism.Methods Mesenchymal stem cells(MSCs) were isolated from healthy human adipose tissue and the exosomes were extracted by ultrafiltration.Rats were divided into four groups: sham group, PBS control group, MSCs treatment group and exosomes treatment group.24 h After TBI, the treatment group was locally injected along the lesion area, 30 μL of PBS, 2×105 MSC, 25 μg protein of exosomes respectively, the total volume was 30 μL.We performed the Modified Neurological Severity Score(mNSS) and the forelimb Foot-Fault Test in all rats before injury and at 1, 3, 7, 10, 13, 16, 21 and 30 days after TBI.The rats were sacrificed at 3 and 7 days after TBI respectively,total RNA was extracted from rat brain tissue.The expression of TNF-α and IL-1β were detected by quantitative PCR.The rats were also killed at 30 days after TBI for testing the neuronal apoptosis in lesion area by tunel-neun double imm-unofluorescence.Results Exosomes treatment significantly promotes the recovery of neurological deficits caused by TBI,and the therapeutic effect is similar to MSCs, its possible mechanism may be the inhibition of the acute inflammation and the reducing of the neurons apoptosis after TBI.Conclusions Exosomes extracted from human adipose-derived mesenchymal stem cellshas promoted neurological functionrecovery after traumatic brain injury, which will provide a new and safer TBI treatment for clinical practice.