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Neuroscience research has been increasingly active during the last 2 decades, largely driven by the high prevalence and increasing burden of neurologic disorders. While rodents are essential models for biomedical research of neurologic disorders, they lack similar brain anatomy and protein expression profiles to humans, thus limiting their translational value as models of traumatic brain injury, stroke, Alzheimer's disease, and Parkinson's disease. The use of ferrets as a model species in neuroscience has been increasing due to their neuroanatomical similarities with humans, including a gyrencephalic brain and larger white matter-to-gray matter ratio. Compared with nonhuman primates, sheep, and swine, ferrets also have the advantages of reduced size, lower housing costs, and lower phylogenetic order. These, among other advantages, make ferrets a promising species to bridge research gaps and complement traditional rodent studies. Although modern neuroscience research in ferrets relies heavily on advanced imaging techniques such as magnetic resonance imaging (MRI), most of the preclinical MRI installations are not designed or optimized for use with ferrets. In this paper we discuss the intricacies and limitations that need to be considered when performing ferret MRI procedures. Reviews of ferret biologic peculiarities, anesthetic protocols, management of complications, and the impact of these factors on MRI outcomes are presented. Standardizing anesthesia protocols for the conduct of MRI in ferrets will aid in better physiologic monitoring as well as imaging outcomes that ultimately benefit the science being conducted.

Background: We aimed to investigate whether combined phosphorous ( 31 P) magnetic resonance spectroscopic imaging (MRSI) and quantitative T 2 ' mapping are able to detect alterations of the cerebral oxygen extraction fraction (OEF) and intracellular pH (pH i ) as markers the of cellular energy metabolism in cerebral small vessel disease (SVD)., Materials and Methods: 32 patients with SVD and 17 age-matched healthy control subjects were examined with 3-dimensional  31 P MRSI and oxygenation-sensitive quantitative T 2 ' mapping (1/ T 2 '  = 1/T 2 * - 1/T 2 ) at 3 Tesla (T). PH i  was measured within the white matter hyperintensities (WMH) in SVD patients. Quantitative T 2 ' values were averaged across the entire white matter (WM). Furthermore, T 2 ' values were extracted from normal-appearing WM (NAWM) and the WMH and compared between patients and controls., Results: Quantitative T 2 ' values were significantly increased across the entire WM and in the NAWM in patients compared to control subjects (149.51 ± 16.94 vs. 138.19 ± 12.66 ms and 147.45 ± 18.14 vs. 137.99 ± 12.19 ms, p  < 0.05). WM T 2 ' values correlated significantly with the WMH load (ρ=0.441, p  = 0.006). Increased T 2 ' was significantly associated with more alkaline pH i  (ρ=0.299, p  < 0.05). Both T 2 ' and pH i were significantly positively correlated with vascular pulsatility in the distal carotid arteries (ρ=0.596, p  = 0.001 and ρ=0.452, p  = 0.016)., Conclusions: This exploratory study found evidence of impaired cerebral OEF in SVD, which is associated with intracellular alkalosis as an adaptive mechanism. The employed techniques provide new insights into the pathophysiology of SVD with regard to disease-related consequences on the cellular metabolic state., Competing Interests: The authors declare that there are no conflicts of interest related to this article., (© 2023 The Author(s).)

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a rare chronic central-nervous-system inflammatory disorder that became known only recently, and the pathogenesis of CLIPPERS remains poorly understood. This report presents clinical and radiological features of a rare case: a young female patient who rapidly died of suspected CLIPPERS. Helpful multiparametric MRI diagnostic criteria are proposed that can help discriminate CLIPPERS from non-CLIPPERS pathologies. We reviewed clinical history, symptoms, quantitative data from brain multiparametric MRI before and after treatment, and histopathological data. Perfusion-weighted imaging revealed a decrease in regional cerebral blood flow by 31% and in cerebral blood volume by 64%, with a moderate increase in transit time and in time to peak by up to 23% in affected pontine and cerebral white matter. As estimated by diffusion tensor imaging, there was elevated density of tracts (n/mm 2 ) and a decrease of fraction anisotropy (×10 -3 mm/s 2 ) in the patient's pons as compared to a healthy control: density of tracts = 13.5 vs 12.4 and fraction anisotropy = 0.32 vs 0.45, respectively. Macromolecular proton fraction values proved to be reduced (15.8% and 14.5% in the control, respectively) in the patient's cerebral peduncles by 3% and in the pons by 4.1% and in a periventricular white matter lesion by 6.4% (11.3% in the normal-looking contralateral hemisphere). Based on our findings, we argue that quantitative MRI techniques may be a valuable source of biomarkers and reliable diagnostic criteria and can shed light on the pathogenesis and exact nosological position of this disorder., (© 2022 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

Spinal cord injuries pose grave medical and socioeconomic burdens warranting measures for early diagnosis, triaging, prognostication and therapeutics. Imaging has since long played a pivotal role in this regard, with continuing research and technological advancements opening newer frontiers. One such advanced Magnetic resonance (MR) technique is Diffusion tensor imaging (DTI) which assesses cord microstructure by tracking the movement of water molecules in biological tissues. DTI utilizes the principle of anisotropy exhibited by the normal compact white matter (WM) tracts of the cord, in which direction-dependent water molecular motion is seen along the axonal axis. Disruption of this complex structure in response to injury alters the movement of these molecules, interrupting anisotropy and thereby DTI metrics. Evaluation of DTI images can be done both by quantitative indices, of which fractional anisotropy (FA) and mean diffusivity (MD) are the most commonly used and by qualitative fiber tracking (tractography) methods in which three-dimensional WM tracts are reconstructed by algorithmic post-processing. Reduced FA is consistently seen at injury sites as a direct consequence of disturbance of anisotropy. Diffusivity values are however more variable with both high and low values recorded across studies. 3D tractography images allow visual assessment of cord integrity, morphology, and orientation. Significant correlation is found between DTI parameters and various spinal injury scores. Furthermore, DTI also helps in accurate lesion mapping and in assessing cord changes distant from injury epicenter providing a holistic evaluation. From its inception, consistent progress in the understanding and application of DTI has effectuated its clinical utility and impact. Incorporation into day-to-day diagnostics is however still challenging, due to suboptimal image acquisition, difficult post-processing, and lack of standardized protocols & image interpretation guidelines. Further research with technical validation, development of normative and disease data sets, and histological confirmation will help establish this novel technique in routine diagnostics., (© 2022 Delhi Orthopedic Association. All rights reserved.)