The cortical hand knob region of the brain is a knob-like segment of the precentral gyrus, projecting into the middle genu of the central sulcus. This anatomic landmark is responsible for intricate control of hand motor movements and has often been implicated in motor weakness following stroke. In some instances, damage to this area has been mistaken for peripheral causes of hand weakness. Our article aims to consolidate clinically relevant information on the cortical hand knob area in a comprehensive review to guide clinicians regarding diagnosis and treatment strategies. We conducted a systematic search within the Medline/PubMed database for reports of strokes in the cortical hand knob region. All studies were published electronically up until December 2023. The search was conducted using the keyword “hand knob”. A total of 24 reports containing 150 patients were found. The mean and median ages were 65 and 67 years, respectively. Sixty-two percent of the individuals were male. According to the TOAST criteria for the classification of the stroke, 59 individuals had a stroke due to large-artery atherosclerosis, 8 had small-vessel occlusion, 20 had cardioembolism, 25 were determined, and 38 were undetermined. The most common etiologies for stroke in the hand knob area can be attributed to large vessel occlusions, small vessel occlusions, or cardioembolism. Presentations following damage to this area can mimic ulnar, median, or radial neuropathy as well. Our comprehensive review serves as a resource for recognizing and managing stroke in the cortical hand knob area.

A Narrative Review of Stroke of Cortical Hand Knob Area

Background Childhood hand function is considered to be one of the strongest predictors of the ability to participate in daily activities as children with cerebral palsy (CP) reach adulthood. The manual ability classification system (MACS) is currently the most widely used for grading hand function in children with CP. However, the MACS method is subjective and may be affected by the raters’ experience. Hand knob is an important control center for hand movement. Therefor this study aimed to develop and validate an objective model for hand function estimation in children with CP and visualize it as a nomogram. Methods A total of 70 Children (2–12 years old) with CP underwent magnetic resonance imaging (MRI) scanning, MACS assessment. According to MACS, children with CP were divided into mild impairment group (grade I–III) and severe impairment group (grade IV–V). Hand function prediction models based on (I) hand knob score, (II) clinical features, and (III) the combination of clinical features and hand knob score were developed and validated separately. The models were subjected to stepwise regression according to the maximum likelihood method, and the Akaike information criterion was used to select the best model. Model discrimination was assessed using receiver operating characteristic (ROC) and calibration curves. The nomogram was finally built according to the best model. Results The area under the curve (AUC) of the hand knob score model in the training set was 0.752, the clinical features model was 0.819, and the hand knob score and clinical features combined model was 0.880. The AUC of the hand knob score model in the validation set was 0.765, the clinical features model was 0.782, and the combined model was 0.894. The best model was the hand knob score-clinical features combined model, and the nomogram finally incorporated two assessment items: the hand knob score and white matter injury. The estimated probability of hand function injury degree of the combined model displayed good agreement with the actual occurrence probability. Conclusions The hand knob score-clinical features combined model can be used to preliminarily assess the degree of hand impairment in children with CP, with good calibration.

/pdf/development-and-validation-of-a-novel-model-based-on-hand-2ymj8e2y.pdf

Development and validation of a novel model based on hand knob score and white matter injury on MRI to predict hand function in children with cerebral palsy

This study was to systematically assess the occipital lobe gray and white matter volume of isolated ventriculomegaly (IVM) fetuses with MRI and to follow up the neurodevelopment of participants. MRI was used to evaluate 37 IVM fetuses and 37 control fetuses. The volume of gray and white matter in each fetal occipital gyrus was manually segmented and compared, and neurodevelopment was followed up and assessed in infancy and early childhood. Compared with the control group, the volume of gray matter in occipital lobe increased in the IVM group, and the incidence of neurodevelopmental delay increased. We tested the hypothesis that prenatal diagnosis IVM represents a biological marker for development in fetal occipital lobe. Compared with the control group, the IVM group showed differences in occipital gray matter development and had a higher risk of neurodevelopmental delay.

Volume development changes in the occipital lobe gyrus assessed by MRI in fetuses with isolated ventriculomegaly correlate with neurological development in infancy and early childhood

OBJECTIVE
To evaluate the consistency and reproducibility of aortic root measurements by Anythink, a semi-automated preoperative CT analysis software, with those of 3mensio.


METHODS
Sixty-seven patients undergoing transcatheter aortic valve replacement (TAVR) in the First Medical Center of Chinese PLA General Hospital from December, 2016 to February, 2022 were retrospectively enrolled in this study. A cardiology resident who completed his professional training used both the software Anythink and 3mensio (as the gold standard) to reconstruct the aortic root model and analyze the parameters of the aortic annulus and the surrounding structures. The correlation and consistency of the measurement results of two software were analyzed. Two independent residents also used Anythink software to repeat the measurements for the same patient for assessment of the reproducibility of Anythink measurements. The valve models were selected based on the measurements by Anythink and 3mensio, and similarities and differences of the two software in clinical valve selection were assessed.


RESULTS
The measurements of the distances from the anulus plane to the left and right coronary ostium, average diameter of the anulus, anulus area, anulus perimeter, and the angle between the annulus and horizontal plane did not differ significantly between the two software (P > 0.05), and their measurements showed positive correlations (r= 0.884-0.981, P < 0.01). The intra-group and inter-group correlation coefficients of the anulus parameters measured by Anythink ranged from 0.894 to 0.992 and from 0.651 to 0.954, respectively. The Kappa-test values of valve models selected by Anythink and 3mensio based on the average diameter, area diameter and perimeter diameter were 0.886, 0.796 and 0.775, respectively. The intra-group Kappa values for the valve models selected based on Anythink measurements were 0.819, 0.841, and 0.795, and the inter-group Kappa values were 0.812, 0.812, and 0.768, respectively. Compared with the measurements by 3mensio, the recommended area diameter measured by Anythink was slightly greater in patients with postoperative paravalvular leakage, but slightly smaller in patients with postoperative new-onset conduction block.


CONCLUSION
Anythink has excellent measurement consistency and high reproducibility for aortic root measurements, and trained cardiologists can use Anythink to obtain accurate aortic root parameters before TAVR.

[Anythink for CT-based aorta root measurements before transcatheter aortic valve replacement: measurement consistency with 3mensio and impact on short-term prognosis].

Background: Although it is critically important to understand the underlying molecular and electrophysiological changes that predispose to the induction and maintenance of atrial fibrillation (AF), the underlying mechanism of AF is still poorly defined. AF is characterized as the electrophysiological and membrane integrity abnormality of the atrial cells, and claudin-5 (Cldn5), a tight junction protein, may be involved in the pathophysiology of AF, however, the role of Cldn5 in AF is unknown. Methods: Left atrial appendages from the enlarged left atrium were obtained from AF patients undergoing modified radiofrequency ablation maze procedure and normal left atrial appendages were obtained from non-AF donors. Western blot, immunofluorescence, transmission electron microscope (TEM), and proteomics analysis were performed to screen the specific protein expression and signal pathway changes in AF heart tissue vs. non-AF heart tissue. In addition, Cldn5 shRNA or siRNA adeno-associated virus (AAV) were then injected into the mouse left ventricle or added into HL1 cells respectively to knockdown claudin-5 in cardiomyocytes to observe whether the change of Cldn5 influences electrophysiology and affects those protein expressions stem from the proteomic analysis. Mitochondrial density and membrane potential were also measured by Mito tracker staining and JC-1 staining under the confocal microscope in vitro. Results: The protein level of claudin-5 was significantly decreased in cardiomyocytes from the left atrium of AF patients compared to non-AF donors. Proteomics analysis showed that 83 proteins were downregulated and 102 proteins were upregulated in the left atrial appendage of AF patients. Among them, CACNA2D2, CACNB2, MYL2 and MAP6 were dramatically downregulated. KEGG pathway analysis showed these changes would lead to hypertrophic and/or dilated cardiomyopathy. Cldn5 shRNA AAV infection induced-Cldn5 deficiency caused severe cardiac atrophy and arrhythmias in mice. The decreases in both mitochondrial numbers and mitochondrial membrane potential (MMP) were also observed in vitro after Cldn5 knockdown by siRNA. Finally, western blot analysis confirmed the protein level of CACNA2D2, CACNB2, MYL2 and MAP6 were downregulated after Cldn5 knockdown in vivo and in vitro. Conclusions: We demonstrated for the first time the deficiency of Cldn5 in cardiomyocytes in the left atrium of AF patients. The mechanism of AF might be associated with Cldn5 deficiency-associated downregulation of CACNA2D2, CACNB2, MYL2 and MAP6, and mitochondrial dysfunction in cardiomyocytes.

Atrial fibrillation is associated with decreased claudin-5 in cardiomyocyte

BACKGROUND AND PURPOSE: Knowledge of anatomic markers of the hand motor cortex is essential in the evaluation and treatment of motor neurologic diseases for both adults and developing populations. However, hand motor cortex variants in developing brains remain to be investigated. Our objective was to observe morphologic variants of the hand motor cortex in developing brains from neonates through childhood. MATERIALS AND METHODS: In this study, 542 participants (0∼15 years of age) were retrospectively enrolled and divided into different age groups. The hand motor cortex morphology was evaluated on the basis of 3D T1WI. Variations in hand motor cortex variants were compared among different age groups. Inter-gender and interhemispheric differences of hand motor cortex variants were also evaluated. RESULTS: Various hand motor cortex variants could be observed in developing brains, even in the neonatal period. One new morphologic shape, “immature Ω,” was found in neonates and infants. The proportion of this new shape decreased dramatically during the first year after birth, then disappeared after 1 year of age. It persisted for a longer time in the right hemisphere and in males. However, sex or hemispheric effects on the distribution of the proportion of variants were not statistically significant. Furthermore, the proportion of concordance of the bilateral hand motor cortex showed an increasing trend with age (P = .006), higher in females than males. CONCLUSIONS: Various hand motor cortex variants already existed at birth. The distribution of proportions of different variants developmentally varied during the first year after birth and became stable after 1 year of age. The concordance of the bilateral hand motor cortex could be influenced by age and sex.

http://www.ajnr.org/content/ajnr/43/2/292.full.pdf

Morphologic Variants of the Hand Motor Cortex in Developing Brains from Neonates through Childhood Assessed by MR Imaging

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[Anythink for CT-based aorta root measurements before transcatheter aortic valve replacement: measurement consistency with 3mensio and impact on short-term prognosis].

Atrial fibrillation is associated with decreased claudin-5 in cardiomyocyte

Morphologic Variants of the Hand Motor Cortex in Developing Brains from Neonates through Childhood Assessed by MR Imaging