Disruption of Conscious Access in Psychosis Is Associated with Altered Structural Brain Connectivity

According to global neuronal workspace (GNW) theory, conscious access relies on long-distance cerebral connectivity to allow a global neuronal ignition coding for conscious content. In patients with schizophrenia and bipolar disorder, both alterations in cerebral connectivity and an increased threshold for conscious perception have been reported. The implications of abnormal structural connectivity for disrupted conscious access and the relationship between these two deficits and psychopathology remain unclear. The aim of this study was to determine the extent to which structural connectivity is correlated with consciousness threshold, particularly in psychosis. We used a visual masking paradigm to measure consciousness threshold, and diffusion MRI tractography to assess structural connectivity in 97 humans of either sex with varying degrees of psychosis: healthy control subjects (n = 46), schizophrenia patients (n = 25), and bipolar disorder patients with (n = 17) and without (n = 9) a history of psychosis. Patients with psychosis (schizophrenia and bipolar disorder with psychotic features) had an elevated masking threshold compared with control subjects and bipolar disorder patients without psychotic features. Masking threshold correlated negatively with the mean general fractional anisotropy of white matter tracts exclusively within the GNW network (inferior frontal-occipital fasciculus, cingulum, and corpus callosum). Mediation analysis demonstrated that alterations in long-distance connectivity were associated with an increased masking threshold, which in turn was linked to psychotic symptoms. Our findings support the hypothesis that long-distance structural connectivity within the GNW plays a crucial role in conscious access, and that conscious access may mediate the association between impaired structural connectivity and psychosis.     

Computer-Aided Diagnosis of Vertebral Compression Fractures Using Convolutional Neural Networks and Radiomics

Journal of Digital Imaging - Vertebral Compression Fracture (VCF) occurs when the vertebral body partially collapses under the action of compressive forces. Non-traumatic VCFs can be secondary to...     

Microstructural changes of the dentato‐rubro‐thalamic tract after transcranial MR guided focused ultrasound ablation of the posteroventral VIM in essential tremor

Essential tremor is the most common movement disorder in adults. In patients who are not responsive to medical treatment, functional neurosurgery and, more recently, transcranial MR‐guided focused ultrasound thalamotomy are considered effective therapeutic approaches. However, the structural brain changes following a thalamotomy that mediates the clinical improvement are still unclear. In here diffusion weighted images were acquired in a cohort of 24 essential tremor patients before and 3 months after unilateral transcranial MR‐guided focused ultrasound thalamotomy targeting at the posteroventral part of the VIM. Microstructural changes along the DRTT were quantified by means of probabilistic tractography, and later related to the clinical improvement of the patients at 3‐months and at 1‐year after the intervention. In addition the changes along two neighboring tracts, that is, the corticospinal tract and the medial lemniscus, were assessed, as well as the relation between these changes and the presence of side effects. Thalamic lesions produced local and distant alterations along the trajectory of the DRTT, and each correlated with clinical improvement. Regarding side effects, gait imbalance after thalamotomy was associated with greater impact on the DRTT, whereas the presence of paresthesias was significantly related to a higher overlap between the lesion and the medial lemniscus. This work represents the largest series describing the microstructural changes following transcranial MR‐guided focused ultrasound thalamotomy in essential tremor. These results suggest that clinical benefits are specific for the impact on the cerebello‐thalamo‐cortical pathway, thus reaffirming the potential of tractography to aid thalamotomy targeting.     

A comparison of physical comorbidities in patients with posttraumatic stress disorder developed after a terrorist attack or other traumatic event

No study investigated whether the presence of specific medical comorbidities is associated with the type of traumatic event, in particular with terrorist attack (TA). In a group of subjects with posttraumatic stress disorder (PTSD), the current study investigated the association between the types of traumatic event (TA vs. other traumatic event [OTE]) and medical comorbidities, controlling for sex and PTSD duration. The Mini International Neuropsychiatric Interview, the Clinician-Administered PTSD Scale, and the Davidson Trauma Scale were administered to 84 subjects diagnosed with PTSD. Thirty-nine were victims of TA and 45 victims of OTE. TA was associated with higher prevalence of neoplasms (β = 2.60, p = 0.02). Females were more protected than males from circulatory system comorbidities (β = 1.47, p = 0.04), while PTSD duration was associated with higher prevalence of such comorbidities (β = 0.005, p = 0.01). Females showed a higher prevalence of neoplasms than males (β = 2.50, p = 0.02). Female sex was protective against metabolic syndrome (β = −1.79, p = 0.02). Patients with PTSD due to TA and female patients should be considered for their higher prevalence of neoplasms, while male patients and those with higher symptom duration should be monitored for circulatory disease and metabolic syndrome. Symptom duration might be associated with circulatory and metabolic disease. Implications for tailored and timely psychopharmacological and psychotherapeutic intervention for PTSD are discussed focusing on these specific medical comorbidities.     

New drugs in early-stage clinical trials for allergic rhinitis

Introduction: Allergic rhinitis (AR) is the most common allergic disease, and it has a relevant impact on the quality of life of the patient. Treatment of AR includes a combination of strategies of proven efficacy and effectiveness; however, a relevant proportion of patients remain uncontrolled.

Areas covered: This review article summarizes emerging therapeutic approaches to AR; these approaches include nasal sprays, oral drugs, alternative allergen immunotherapy administration routes, and biologic agents.

Expert opinion: The agents discussed require further clinical trials to prove their efficacy in the treatment of AR. Some of these agents, in particular, allergen immunotherapies and biologics, have the potential to form crucial precision medicine approaches to AR. Those that prove their efficacy in clinical trials must also be evaluated from a pharmacoeconomic perspective, possibly in real-life studies; this will define which therapeutic strategies achieve the most convenient and cost-effective ratio, thus yielding a novel opportunity for the most severe and previously treatment-resistant allergic patients.