Functional connectivity-based classification of rapid eye movement sleep behavior disorder

BACKGROUND: Isolated rapid eye movement sleep behavior disorder (iRBD) is a clinically important parasomnia syndrome preceding α-synucleinopathies, thereby prompting us to develop methods for evaluating latent brain states in iRBD. Resting-state functional magnetic resonance imaging combined with a machine learning-based classification technology may help us achieve this purpose. METHODS: We developed a machine learning-based classifier using functional connectivity to classify 55 patients with iRBD and 97 healthy elderly controls (HC). Selecting 55 HCs randomly from the HC dataset 100 times, we conducted a classification of iRBD and HC for each sampling, using functional connectivity. Random forest ranked the importance of functional connectivity, which was subsequently used for classification with logistic regression and a support vector machine. We also conducted correlation analysis of the selected functional connectivity with subclinical variations in motor and non-motor functions in the iRBDs. RESULTS: Mean classification performance using logistic regression was 0.649 for accuracy, 0.659 for precision, 0.662 for recall, 0.645 for f1 score, and 0.707 for the area under the receiver operating characteristic curve (p < 0.001 for all). The result was similar in the support vector machine. The classifier used functional connectivity information from nine connectivities across the motor and somatosensory areas, parietal cortex, temporal cortex, thalamus, and cerebellum. Inter-individual variations in functional connectivity were correlated with the subclinical motor and non-motor symptoms of iRBD patients. CONCLUSIONS: Machine learning-based classifiers using functional connectivity may be useful to evaluate latent brain states in iRBD

Therapeutic strategies for pseudoaneurysm following blunt liver and spleen injuries: a multicenter cohort study in the pediatric population

BACKGROUND: Little guidance exists for the treatment of pseudoaneurysm following pediatric blunt liver and/or spleen injuries (BLSI). We aimed to describe the incidence of delayed pseudoaneurysm development and the subsequent clinical course of pseudoaneurysm in pediatric BLSI. METHODS: This multicenter retrospective cohort study from Japan included pediatric patients (≤16 years old) who sustained BLSI from 2008 to 2019. The cohort was divided into four groups based on hemostatic intervention within 48 hours of admission, namely non-operative management (NOM), NOM with interventional radiology (IR), operative management (OM), and combined IR/OM. Descriptive statistics were used to describe the incidence of delayed pseudoaneurysm among the groups and to characterize the clinical course of any pseudoaneurysms. RESULTS: A total of 1, 407 children (median age, 9 years) from 83 institutions were included. The overall number (incidence) of cases of delayed pseudoaneurysm formation was 80 (5.7%), and the number with delayed pseudoaneurysm rupture was 16 (1.1%) cases in the entire cohort. Patients treated with NOM (1056), NOM with IR (276), OM (53), and combined IR/OM (22) developed 43 (4.1%), 32 (12%), 2 (3.8%), and 3 (14%) delayed pseudoaneurysms, respectively. Among patients who developed any pseudoaneurysms, 39% of patients underwent prophylactic IR for unruptured pseudoaneurysm, while 13% required emergency angioembolization for delayed pseudoaneurysm rupture, with one ruptured case requiring total splenectomy. At least 45% of patients experienced spontaneous resolution of pseudoaneurysm without any interventions. CONCLUSION: Our results suggest that the risk of delayed pseudoaneurysm still exists even after acute phase IR as an adjunct to NOM for BLSI in children, indicating the necessity of a period of further observation. While endovascular interventions are usually successful for pseudoaneurysm management, including rupture cases, given the high incidence of spontaneous resolution, the ideal management of pseudoaneurysm remains to be investigated in future studies. LEVEL OF EVIDENCE: Level 4; Therapeutic/Care management

Functional connectivity-based classification of rapid eye movement sleep behavior disorder

BACKGROUND: Isolated rapid eye movement sleep behavior disorder (iRBD) is a clinically important parasomnia syndrome preceding α-synucleinopathies, thereby prompting us to develop methods for evaluating latent brain states in iRBD. Resting-state functional magnetic resonance imaging combined with a machine learning-based classification technology may help us achieve this purpose. METHODS: We developed a machine learning-based classifier using functional connectivity to classify 55 patients with iRBD and 97 healthy elderly controls (HC). Selecting 55HCs randomly from the HC dataset 100 times, we conducted a classification of iRBD and HC for each sampling, using functional connectivity. Random forest ranked the importance of functional connectivity, which was subsequently used for classification with logistic regression and a support vector machine. We also conducted correlation analysis of the selected functional connectivity with subclinical variations in motor and non-motor functions in the iRBDs. RESULTS: Mean classification performance using logistic regression was 0.649 for accuracy, 0.659 for precision, 0.662 for recall, 0.645 for f1 score, and 0.707 for the area under the receiver operating characteristic curve (p<0.001 for all). The result was similar in the support vector machine. The classifier used functional connectivity information from nine connectivities across the motor and somatosensory areas, parietal cortex, temporal cortex, thalamus, and cerebellum. Inter-individual variations in functional connectivity were correlated with the subclinical motor and non-motor symptoms of iRBD patients. CONCLUSIONS: Machine learning-based classifiers using functional connectivity may be useful to evaluate latent brain states in iRBD

Therapeutic strategies for pseudoaneurysm following blunt liver and spleen injuries: a multicenter cohort study in the pediatric population

BACKGROUND: Little guidance exists for the treatment of pseudoaneurysm following pediatric blunt liver and/or spleen injuries (BLSI). We aimed to describe the incidence of delayed pseudoaneurysm development and the subsequent clinical course of pseudoaneurysm in pediatric BLSI. METHODS: This multicenter retrospective cohort study from Japan included pediatric patients (≤16 years old) who sustained BLSI from 2008 to 2019. The cohort was divided into four groups based on hemostatic intervention within 48 hours of admission, namely non-operative management (NOM), NOM with interventional radiology (IR), operative management (OM), and combined IR/OM. Descriptive statistics were used to describe the incidence of delayed pseudoaneurysm among the groups and to characterize the clinical course of any pseudoaneurysms. RESULTS: A total of 1, 407 children (median age, 9 years) from 83 institutions were included. The overall number (incidence) of cases of delayed pseudoaneurysm formation was 80 (5.7%), and the number with delayed pseudoaneurysm rupture was 16 (1.1%) cases in the entire cohort. Patients treated with NOM (1056), NOM with IR (276), OM (53), and combined IR/OM (22) developed 43 (4.1%), 32 (12%), 2 (3.8%), and 3 (14%) delayed pseudoaneurysms, respectively. Among patients who developed any pseudoaneurysms, 39% of patients underwent prophylactic IR for unruptured pseudoaneurysm, while 13% required emergency angioembolization for delayed pseudoaneurysm rupture, with one ruptured case requiring total splenectomy. At least 45% of patients experienced spontaneous resolution of pseudoaneurysm without any interventions. CONCLUSION: Our results suggest that the risk of delayed pseudoaneurysm still exists even after acute phase IR as an adjunct to NOM for BLSI in children, indicating the necessity of a period of further observation. While endovascular interventions are usually successful for pseudoaneurysm management, including rupture cases, given the high incidence of spontaneous resolution, the ideal management of pseudoaneurysm remains to be investigated in future studies. LEVEL OF EVIDENCE: Level 4; Therapeutic/Care management