Neuroimaging

Background/Objectives: MRI-guided neurovascular interventions could benefit from lower-field systems due to reduced magnetic and radiofrequency hazards. However, safety and practical visibility of commonly used neurointerventional devices at 0.55 T remain insufficiently characterized. We evaluated magnetic field interactions, RF-induced heating, and qualitative device visibility in 11 commercially available and commonly used neurovascular devices on a 0.55 T MRI system. Methods: Eleven devices, including stent retrievers, guidewires, catheters, and one embolization implant, were tested at 0.55 T. Magnetostatic interactions were quantified using the American Society for Testing and Materials (ASTM)-guided deflection methods for translational force (ASTM-F2052) and a two-string suspension apparatus for torque (adapted from Stoianovici et al.). RF-induced heating was measured in an in vitro perfused cerebral vessel phantom using a 15 min high-specific absorption rate spin echo sequence under static and flow conditions. Qualitative device visibility was assessed using a turbo spin echo (TSE) and balanced steady-state free precession (bSSFP) imaging on each device individually. Results: Eight of eleven devices passed the translational force test, while three devices (D, E, and G), containing significant ferromagnetic components, failed with deflection angles > 45°. Eight devices passed torque testing, remaining below the critical threshold in all rotation positions; three devices (D, G, and J) failed by exceeding the 54° criterion, including one guidewire and two devices with braided/coiled metallic structures. Under static conditions, RF-induced heating ranged from negligible to 10.4 °C (maximum in device D) and generally decreased under flow; in the flow configuration, temperature rise remained below 2 °C for 6/11 devices. Qualitative imaging performance differed by sequence, with bSSFP enabling improved delineation of device structure (best for devices A, C, and H), whereas devices D, E, F, and J produced extensive signal voids that precluded reliable visualization in both sequences. Overall, three devices satisfied all safety criteria while remaining clearly visible under MRI. Conclusions: Devices that pass safety thresholds at 0.55 T can serve as candidates for further sequence optimization and preclinical workflow development, enabling the design of low-SAR, device-compatible imaging protocols tailored for neurointerventional workflows. These results provide key safety data supporting the feasibility of MR-guided neurovascular procedures at 0.55 T. Full article

Background/Objectives: Speech-evoked brain potentials provide a window into the neural encoding of speech, experience-dependent plasticity, and deficits in central auditory processing from communication disorders. Stronger and faster frequency-following responses (FFRs) and cortical event-related potentials (ERPs) have been interpreted as reflecting more robust and efficient auditory–sensory processing across brainstem and cortical levels. Importantly, these neural signatures relate to real-world listening skills like speech-in-noise (SIN) perception. How functional FFR/ERPs relate to the underlying anatomical structures that generate these responses in brainstem and cortex is unknown. Methods: Using a multimodal imaging approach, we recorded FFRs and ERPs to clean and noise-degraded speech sounds to assess the strength of listeners’ neural encoding of speech at brainstem (FFR) and cortical (ERP) levels. MRI volumetrics of midbrain and transverse temporal gyrus (Heschl’s gyrus) quantified morphological variation in subcortical and cortical anatomy that underly these EEG potentials. We used the QuickSIN to assess behavioral SIN abilities. Results: We found larger and thicker right (but not left) Heschl’s gyrus was related to listeners’ SIN perception as well as the size of their cortical ERPs. Structural and functional measures interacted at a subcortical level. For listeners with smaller midbrain volumes, larger speech FFRs were associated with better QuickSIN scores, whereas in individuals with larger midbrain volumes, larger FFRs were related to poorer QuickSIN scores. Conclusions: Our findings reveal common functional signatures of speech sound processing (FFRs, ERPs) are related to the anatomy of their underlying generator sources and suggest that both auditory brain structure and function can account for perceptual SIN capacity. Full article

Background: Addictive disorders are characterized by the dysregulation of neural circuits involved in reward processing, salience attribution, emotional regulation, and cognitive control. Traditional neuroimaging paradigms based on static or two-dimensional stimuli show limited ecological validity and may fail to capture the contextual complexity of real-world addictive triggers. Immersive virtual reality (VR) offers a novel approach to simulate realistic, multisensory environments capable of eliciting craving and emotional responses. Although several reviews have examined VR in addictive disorders, most combined immersive and non-immersive tools and did not restrict inclusion to studies with brain-based outcomes. Methods: This systematic review with narrative synthesis was conducted in PubMed/MEDLINE and APA PsycINFO for studies published up to 30 December 2025. This systematic review followed PRISMA 2020 and was prospectively registered in PROSPERO; due to heterogeneity, findings were synthesized narratively. Eligible studies included human participants with substance-related or behavioral addictions and employed immersive VR paradigms (e.g., head-mounted display–based environments) combined with neuroimaging or neurophysiological measures (EEG, fMRI, fNIRS, PET, or DTI). Risk of bias was assessed using ROB-2 or ROBINS-I, and overall certainty of evidence was evaluated with the GRADE framework. Results: Ten studies met the inclusion criteria, encompassing over 1450 participants with alcohol, nicotine, methamphetamine, opioid use disorders, and internet gaming disorder. Immersive VR was associated with craving-related neural responses across modalities, involving prefrontal, insular, limbic, and striatal networks. EEG studies reported spectral power changes associated with craving and attentional salience, while fMRI, fNIRS, and PET studies demonstrated activation and modulation of executive control and reward-related circuits. Preliminary longitudinal and interventional studies indicate that repeated VR exposure may induce neurobiological changes consistent with therapeutic modulation. Conclusions: Immersive VR combined with neuroimaging supports the use of immersive VR as an ecologically grounded framework to probe addiction-related brain circuits; however, larger trials and standardized reporting are needed to strengthen clinical translation. Future studies should prioritize adequately powered randomized designs, harmonized VR cue-reactivity paradigms, and transparent neuroimaging reporting to enable reproducibility and cumulative inference. Full article

In this case report, we described the pitfalls in the differential diagnosis of a pituitary stalk lesion in a patient affected by Klinefelter Syndrome (KS) that was initially suspected of infundibulo-neuro-hypophysitis (INH). According to the atypical radiological picture for INH, the not-conclusive pathology findings, and the partial response to glucocorticoid treatment, a [18F] fluorocholine ([18F] FCH) positron emission computed tomography (PET-CT) scan was performed and identified a pituitary stalk proliferative lesion that was suggestive for neoplasia. This clinical case emphasizes the prospective and potential diagnostic role of the [18F] FCH PET-CT in pituitary stalk lesions and in the diagnosis of pituitary germinoma. Our article also includes a brief review of the literature, focusing on the differential diagnosis of lesions involving the pituitary stalk, the oncological risk associated with KS, and the role of nuclear imaging in the evaluation of such cases. Full article

Background: Traumatic subarachnoid hemorrhage (tSAH) is a common and clinically significant component of traumatic brain injury (TBI), contributing to complications such as vasospasm, delayed cerebral ischemia, and long-term neurological impairment. This review examines how contemporary imaging approaches enhance the diagnosis, monitoring, and management of tSAH. Methods: A systematic search of major databases identified studies evaluating imaging strategies relevant to tSAH within the broader context of TBI. Results: CT remains the primary modality for acute identification of subarachnoid blood and associated mass effect, while MRI offers greater sensitivity for soft-tissue injury and secondary pathological changes. Quantitative and functional imaging techniques provide emerging insights into microstructural damage, perfusion disturbances, and metabolic dysfunction, though their integration into routine clinical practice remains limited. Conclusion: Imaging plays a central role in the evaluation of tSAH and supports key clinical decisions throughout TBI management. Standard methods such as CT and MRI remain indispensable, while newer quantitative and functional techniques may refine risk stratification and enable more personalized care as evidence for their clinical utility continues to grow. Full article

The study of the nervous system in health and disease presents an extraordinary scientific challenge, one deeply rooted in the intrinsic complexity of brain structure and function across multiple scales of biological organization. The nervous system is not only a dense network of billions of neuronal and non-neuronal cells (i.e., glial cells) but is also a dynamic system influenced by genetic, molecular, cellular, systemic, metabolic, environmental, and social factors that collectively and continuously shape neurocognitive and physiological outcomes. Understanding this multifaceted system demands a multiscale integrated approach, spanning from the molecular and cellular levels to the macroscopic and population scales, leveraging cutting-edge technologies and interdisciplinary expertise. This commentary highlights the complexity inherent to neuroscience research and the critical need for integrated methodologies to advance personalized medicine and effective therapeutic strategies for neurological and psychiatric disorders. Full article