Structural connectivity changes in unilateral hearing loss.

Network connectivity, as mapped by the whole brain connectome, plays a crucial role in regulating auditory function. Auditory deprivation such as unilateral hearing loss might alter structural network connectivity; however, these potential alterations are poorly understood. Thirty-seven acoustic neuroma patients with unilateral hearing loss (19 left-sided and 18 right-sided) and 19 healthy controls underwent diffusion-weighted and T1-weighted imaging to assess edge strength, node strength, and global efficiency of the structural connectome. Edge strength was estimated by pair-wise normalized streamline density from tractography and connectomics. Node strength and global efficiency were calculated through graph theory analysis of the connectome. Pure-tone audiometry and word recognition scores were used to correlate the degree and duration of unilateral hearing loss with node strength and global efficiency. We demonstrate significantly stronger edge strength and node strength through the visual network, weaker edge strength and node strength in the somatomotor network, and stronger global efficiency in the unilateral hearing loss patients. No discernible correlations were observed between the degree and duration of unilateral hearing loss and the measures of node strength or global efficiency. These findings contribute to our understanding of the role of structural connectivity in hearing by facilitating visual network upregulation and somatomotor network downregulation after unilateral hearing loss.

Agenesis of the corpus callosum: What to tell expecting parents?

Agenesis of the corpus callosum (ACC) is one of the most common brain malformations, with an incidence estimated to range from 0.5 to 70 in 10,000 among the general population. Prenatal diagnosis is made via ultrasound; however, fetal MRI is useful to confirm or exclude the presence of associated cerebral abnormalities-mostly cortical malformations-that may affect postnatal prognosis. When no additional central nervous system (CNS) or extra CNS anomalies are identified and no genetic cause is found, an isolated ACC is diagnosed. Overall, in cases of ACC, an underlying genetic cause can be identified in up to 12.5% with chromosomal microarray (CMA) and up to 47% with whole exome sequencing (WES). In cases where ACC is the only anomaly detected, the yield of WES is 30%. Postnatal outcomes are variable and depend on whether the condition is isolated or not. In truly isolated ACC, outcomes range from normal in 65% of cases through mild to severe neurodevelopmental impairments in 35% of cases. An interdisciplinary team of medical experts is key in guiding parents toward informed decision-making in pregnancies complicated by ACC. Considering current and expected advancements in genetic testing and imaging technologies in upcoming years, we herein summarize current recommendations for the management and prenatal counseling of expecting parents of fetuses with ACC. Our review pertains primarily to expecting parents of fetuses with complete ACC.

Brain imaging signatures of neuropathic facial pain derived by artificial intelligence.

Advances in neuroimaging have permitted the non-invasive examination of the human brain in pain. However, a persisting challenge is in the objective differentiation of neuropathic facial pain subtypes, as diagnosis is based on patients' symptom descriptions. We use artificial intelligence (AI) models with neuroimaging data to distinguish subtypes of neuropathic facial pain and differentiate them from healthy controls. We conducted a retrospective analysis of diffusion tensor and T1-weighted imaging data using random forest and logistic regression AI models on 371 adults with trigeminal pain (265 classical trigeminal neuralgia (CTN), 106 trigeminal neuropathic pain (TNP)) and 108 healthy controls (HC). These models distinguished CTN from HC with up to 95% accuracy, and TNP from HC with up to 91% accuracy. Both classifiers identified gray and white matter-based predictive metrics (gray matter thickness, surface area, and volume; white matter diffusivity metrics) that significantly differed across groups. Classification of TNP and CTN did not show significant accuracy (51%) but highlighted two structures that differed between pain groups-the insula and orbitofrontal cortex. Our work demonstrates that AI models with brain imaging data alone can differentiate neuropathic facial pain subtypes from healthy data and identify regional structural indicates of pain.

Do Exercises Prevent Falls Among Older Adults: Where Are We Now? A Systematic Review.

OBJECTIVE: To determine whether single interventions (SI), multifactorial interventions (MI), or multiple component interventions (MCI) including vitamin D supplementation prevent the incidence of falls and fall risk factors among older adults who are community-dwelling or living in long-term care facilities. DESIGN: Systematic review. METHODS: PubMed, Scopus, MEDLINE, and Cochrane were searched with restrictions applied to publication year (2015‒2019) and language (limited to studies published in English). After duplicate removal and title and abstract screening, 2 authors independently identified eligible studies on the basis of inclusion criteria. Risk of bias and quality of evidence were assessed. RESULTS: Thirty-four studies were included after screening titles and abstracts from 855 citations and 129 full-text articles. Thirteen randomized-controlled trials and clinical trials (5 on MI, 1 on MCI, and 7 on SI) including 2232 participants and 21 systematic reviews (assessing SI, MI, MCI, or all) were extracted for qualitative synthesis. Fifteen out of 20 studies that reported outcomes on falls rate found a significant reduction. Seventeen out of 23 studies with outcomes on fall risk factors concluded a significant improvement. Five studies found no significant differences in falls incidence, and 5 studies found no significant differences in fall risks. One study reported worsened outcomes, including poorer balance. CONCLUSION AND IMPLICATIONS: Although results are inconclusive, SI, MI, and MCI involving exercises may prevent falls. Vitamin D supplementation may be beneficial alongside exercise; however, whether vitamin D use consistently reduces falls incidence or fall risks remains uncertain. Exercises that are individually tailored to participants' capabilities and risks may be the most effective falls prevention interventions. Implementation may reduce medical costs and improve quality of life for older adults who are community-dwelling or are living in long-term care facilities.