Inversion Recovery Hyperintense Research Articles

Asymptomatic HyperCKemia in the Pediatric Population: A Prospective Study Utilizing Next-Generation Sequencing and Ancillary Tests.

Persistent elevation of serum creatine kinase levels (hyperCKemia) as an isolated manifestation presents a diagnostic challenge. Genetic myopathies are frequently involved; however, studies using next-generation sequencing (NGS) in pediatric patients are lacking, and the significance of genetic aberrations remains poorly understood. This study, therefore, aimed to investigate the relevance of NGS and the support of contemporary diagnostic tools in the diagnosis of pediatric asymptomatic hyperCKemia. This was a prospective cohort study enrolling pediatric (0-18 years old) patients meeting the predefined criteria for asymptomatic/paucisymptomatic hyperCKemia, excluding DMD gene deletion/duplication, recruited from a referral center. NGS, muscle MRI, EMG, and muscle biopsies with immunolabeling and inflammatory markers were performed according to a prespecified protocol. Data analysis was performed using descriptive/univariate statistics and Bayesian logistic regression. The series comprised 65 patients (78% male). NGS diagnosis was achieved in 55% of the cohort, with 70% of the pathogenic variants involving 7 genes (DMD, CAPN3, ANO5, DYSF, RYR1, GAA, and CAV3). The diagnostic rate was similar across all age groups; however, the gene profiles varied between the childhood and juvenile groups. EMG yielded myopathic features in 48% of the investigated cases, being predictive for diagnosis (p < 0.05; odds ratio [OR] 13.484, 95% CI 1.358-705.297). MRI showed normal (64%), focal fatty change (26%), or short-tau inversion recovery hyperintensity (10%) profiles, which were not predictive of diagnosis but supported muscle biopsy indications. Muscle biopsy provided a significant diagnostic effect (p < 0.05; OR 0.028, 95% CI 0.001-0.238), contributing to myopathologic features clarifying the variant pathogenicity and identifying inflammatory myopathies. The diagnoses remained inconclusive and unresolved in 14% and 29% of the cohorts, respectively. The diagnostic rate for patients with CK levels below the threshold of 3× was 42%. In multivariate analysis, NGS was the only variable achieving a significant diagnostic effect (β = 9.85, 95% CI 4.65-16.09). NGS, as the primary diagnostic tool for investigating hyperCKemia in the pediatric population, yielded a higher diagnostic rate. However, muscle biopsies are necessary to define variants of uncertain pathogenicity and aid in identifying inflammatory myopathies. EMG and MRI may play a role in hyperCKemia characterization, guiding the decision to perform muscle biopsy. The primary limitation of this study was that not all ancillary tests were performed in all recruited patients owing to ethical restrictions, which lowered the power of the predictive analysis.

Vigabatrin-associated brain magnetic resonance imaging abnormalities and clinical symptoms in infants with tuberous sclerosis complex.

Previous retrospective studies have reported vigabatrin-associated brain abnormalities on magnetic resonance imaging (VABAM), although clinical impact is unknown. We evaluated the association between vigabatrin and predefined brain magnetic resonance imaging (MRI) changes in a large homogenous tuberous sclerosis complex (TSC) cohort and assessed to what extent VABAM-related symptoms were reported in TSC infants. The Dutch TSC Registry and the EPISTOP cohort provided retrospective and prospective data from 80 TSC patients treated with vigabatrin (VGB) before the age of 2 years and 23 TSC patients without VGB. Twenty-nine age-matched non-TSC epilepsy patients not receiving VGB were included as controls. VABAM, specified as T2/fluid-attenuated inversion recovery hyperintensity or diffusion restriction in predefined brain areas, were examined on brain MRI before, during, and after VGB, and once in the controls (at approximately age 2 years). Additionally, the presence of VABAM accompanying symptoms was evaluated. Prevalence of VABAM in VGB-treated TSC patients was 35.5%. VABAM-like abnormalities were observed in 13.5% of all patients without VGB. VGB was significantly associated with VABAM (risk ratio [RR] = 3.57, 95% confidence interval [CI] = 1.43-6.39), whereas TSC and refractory epilepsy were not. In all 13 VGB-treated patients with VABAM for whom posttreatment MRIs were available, VABAM entirely resolved after VGB discontinuation. The prevalence of symptoms was 11.7% in patients with VABAM or VABAM-like MRI abnormalities and 4.3% in those without, implicating no significant association (RR = 2.76, 95% CI = .68-8.77). VABAM are common in VGB-treated TSC infants; however, VABAM-like abnormalities also occurred in children without either VGB or TSC. The cause of these MRI changes is unknown. Possible contributing factors are abnormal myelination, underlying etiology, recurrent seizures, and other antiseizure medication. Furthermore, the presence of VABAM (or VABAM-like abnormalities) did not appear to be associated with clinical symptoms. This study confirms that the well-known antiseizure effects of VGB outweigh the risk of VABAM and related symptoms.

Cerebral cortical encephalitis in adults with myelin oligodendrocyte glycoprotein antibody-associated disease: A national case series.

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a relatively recently described disease, most commonly presenting with optic neuritis and longitudinally extensive transverse myelitis. Cerebral cortical encephalitis is a rare manifestation of MOGAD. We identified patients presenting with cerebral cortical encephalitis with positive MOG antibodies in serum across a large specialized service. Demographic and clinical information were collected. We describe clinical and laboratory characteristics, treatment response, and subsequent relapse risk in adults presenting with this phenotype. We identified eight patients meeting clinical criteria for cerebral cortical encephalitis with MOG antibodies. All had seizures; four had focal onset seizures with or without secondary generalization. Two patients exhibited encephalopathy, and six demonstrated focal neurological deficits at presentation. All had fluid-attenuated inversion recovery hyperintensities. Five of eight displayed cerebral swelling, and two of eight displayed leptomeningeal enhancement. Where cerebrospinal fluid (CSF) results were available, five of seven had CSF pleocytosis, protein was raised in two of seven, and one patient had oligoclonal bands unique to CSF. Median time to seizure control was 1.25 months, and all clinical features and magnetic resonance imaging abnormalities resolved. Four of eight patients (50%) had a clinical relapse, with a median time to relapse of 6.4 months. Cerebral cortical encephalitis appears to share similar CSF findings, steroid responsiveness, and risk of relapse with other clinical manifestations of MOGAD. This informs treatment decisions and patient counselling.

Evaluation of arterial spin labeling in the diagnosis and monitoring of myelin oligodendrocyte glycoprotein-associated cerebral cortical encephalitis.

Myelin oligodendrocyte glycoprotein (MOG)-associated disorders are inflammatory demyelinating diseases of the CNS. Cerebral cortical encephalitis (CCE) is characterized by cortical fluid-attenuated inversion recovery hyperintensity with seizures and headaches. We report two cases of MOG antibody-associated CCE (MOG-CCE) evaluated using serial MRI sequences, including arterial spin labeling (ASL), pre- and posttreatment. In both patients, ASL demonstrated hyperperfusion correlating with disease activity, which normalized following steroid therapy. Our cases highlight the usefulness of ASL in early detection, monitoring, and assessment of treatment response in MOG-CCE.

Comparison of distal extremity magnetic resonance imaging findings in Australian racing Standardbreds and Thoroughbreds.

Foot-related lameness is common in Standardbred and Thoroughbred racehorses. Magnetic resonance imaging (MRI) provides information on both the soft tissue and osseous structures of the distal extremity. The aim of this study was to determine whether abnormalities identified on distal limb MRI differed between these two racehorse populations. The records of Standardbred and Thoroughbred racehorse distal extremity MRI examinations conducted at Camden Equine Centre and Ballarat Veterinary Practice between 2013 and 2023 were retrieved. Horses were included if pain causing lameness had been localised to the foot using perineural or intra-articular analgesia. MRI abnormalities of the structures within the distal extremity were recorded and comparisons made between the two groups. There was a significant difference in the rate of occurrence of certain MRI abnormalities between the Thoroughbred and Standardbred racehorse populations, including distal phalangeal fractures, proximal phalangeal short tau inversion recovery (STIR) hyperintensity (distal aspect), the presence and severity of ungular cartilage ossification, abnormalities of the navicular bone distal border synovial invaginations/vascular channels and navicular bone distal border fragments. The presence of distal extremity STIR hyperintensity and fractures was significantly higher in Standardbred compared to Thoroughbred racehorses when these findings were grouped and considered in combination. There were many similarities in the distal extremity MRI abnormalities identified in lame Australian Standardbred and Thoroughbred racehorses. However, distal phalangeal fractures, ungular cartilage ossification and distal extremity STIR hyperintensity were identified in significantly more in Standardbred than Thoroughbred racehorses.

Cerebral Cortical Encephalitis and Other Meningocortical Manifestations of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease in Children: Case Series and Review of the Literature.

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease is a neuroinflammatory disorder (MOGAD) with heterogeneous phenotype including paroxysms of optic neuritis, transverse myelitis, acute disseminated encephalomyelitis, brainstem demyelination, and encephalitis. Fluid-attenuated inversion recovery hyperintense cortical lesions in MOG-associated encephalitis with seizures, or FLAMES, is a manifestation of cerebral cortical encephalitis seen less frequently than other typical MOG antibody-associated disease presentations. Cases of FLAMES are rarer in children, and frequently initially misdiagnosed with infectious meningoencephalitis. Other meningocortical manifestations of MOG antibody-associated disease have been described and likely exist along a continuum. In this retrospective single-center case series, we describe the demographic, clinical, radiographic, laboratory, and electroencephalographic features of 5 children with clinicoradiographic features consistent with the spectrum of MOG-IgG-positive meningocortical syndromes.

Clinical characteristics of overlapping syndrome in patients with GFAP-IgG and MOG-IgG: a case series of 8 patients and literature review.

The overlapping syndrome of anti-GFAP and anti-MOG antibodies is extremely rare. This retrospective study reports 8 adult cases of the GFAP-MOG overlapping syndrome. We reviewed the clinical characteristics of 8 adult patients with the GFAP-MOG overlapping syndrome from Jan 2019 and Sep 2023 at the Third Affiliated Hospital, Sun Yat-sen University. Moreover, we searched the literature and included all case reports with this overlapping syndrome since 2018 on PubMed. The predominant clinical syndrome was meningoencephalomyelitis (5/8), followed by meningoencephalitis (2/8), and myelitis (1/8). Five patients had a flu-like prodromal symptom or diarrhea. No neoplasms were found in these patients. Regarding brain MRI, T2-weighted/fluid-attenuated inversion recovery hyperintensities were in 7 patients and leptomeningeal enhancement was in 4 patients. However, only one patient had periventricular radial linear enhancement. Besides, two patients had large space-occupying lesions. For spinal MRI, T2-hyperintensities were observed in 4 patients, in which 3 patients had longitudinally extensive lesions. All patients were treated with immunotherapy, the median follow-up period was 18months (range, 3-36months). Three patients presented relapses during the follow-up, but all cases recovered to mRS scores ≤ 2 at last follow-up. In addition, we also reviewed 14 cases (including 7 adults and 7 children) with this overlapping syndrome by literature review. Our findings provide data to understandthe clinical features and prognosis of the GFAP-MOG overlapping syndrome. Recognizing this overlapping syndrome will expand our knowledge, allowing for better management of these patients.

AB012. A phase III randomized trial of gross total resection versus possible resection of fluid-attenuated inversion recovery (FLAIR) hyperintensity lesion on magnetic resonance image for newly diagnosed supratentorial glioblastoma (JCOG2209).

Complete resection of contrast-enhanced lesions [gross total resection (GTR)] without severe neurological deficits has been generally accepted as the goal of surgery. However, it remains unclear if additional resection of surrounding fluid-attenuated inversion recovery (FLAIR) hyper-intense lesions combined with GTR (FLAIRectomy) has survival advantage of primary glioblastoma patients. Multicenter, open-label, randomized phase III trial was commenced to confirm the superiority of FLAIRectomy to GTR alone followed by radiotherapy with concomitant and adjuvant temozolomide in terms of overall survival (OS) for primary glioblastoma IDH-wildtype patients. This trial investigates not only survival but also postoperative neurological and neurocognitive deficits in detail. We assumed a 2-year OS of 50% in the GTR arm and expected a 15% improvement in the FLAIRectomy arm. A total of 130 patients is required with a one-sided alpha of 5%, power of 70%, and will be accrued from 49 Japanese institutions in 4 years and follow-up will last 2.5 years. Patients aged 18-75 years will be registered and randomly assigned to each arm with 1:1 allocation. The primary endpoint is OS, and the secondary endpoints are progression-free survival, frequency of adverse events, proportion of Karnofsky performance status preservation, proportion of National Institutes of Health stroke scale preservation, proportion of mini-mental state examination preservation and proportion of health-related quality of life preservation. The Japan Clinical Oncology Group Protocol Review Committee approved this study protocol in May 2023. Ethics approval was granted by the National Cancer Center Hospital Certified Review Board. Patient enrollment began in July 2023. If FLAIRectomy is superior to GTR alone, aggressive surgery will become a standard surgical treatment for glioblastoma with resectable contrast-enhanced lesion. Registry number: jRCT1031230245. Date of registration: 19/July/2023. Date of first participant enrollment: 28/July/2023.

External auditory canal atresia affecting the horizontal canal of a 2‐year‐old Labrador Retriever dog

AbstractA 2‐year‐old, female neutered, Labrador Retriever dog was presented with left otalgia. Otoscopic examination revealed a blind ending left external ear canal. Magnetic resonance imaging confirmed an abrupt narrowing of the lateral aspect of the horizontal canal, medial to which the remaining horizontal ear canal and middle ear cavities contained well‐delineated, homogenous, T2w, fluid‐attenuated inversion recovery and T1w hyperintense, non‐contrast enhancing material. A diagnosis of external auditory canal atresia was made based on the imaging findings. Considering the patient's age and absence of preceding trauma, a congenital cause was considered most likely. Surgical treatment by way of a total ear canal ablation with lateral bulla osteotomy was performed. At the re‐check appointment, the surgical site had healed well and there were no associated complications noted; a telephone call with the owner 5 months later documented no clinical concerns.

Clinical and imaging features of Pseudomonas aeruginosa ventriculitis with suspected obstructive hydrocephalus in a German Shepherd dog

AbstractA 5‐year‐old male neutered German Shepherd dog was evaluated following a seizure for acute and rapidly progressive obtundation, vertical nystagmus and ataxia. Magnetic resonance imaging exhibited marked hydrocephalus in the lateral ventricles with cerebellar herniation through the foramen magnum. In the periventricular tissues, T2‐weighted fluid‐attenuated inversion recovery hyperintensity was present, representing periventricular oedema. The ventricular walls were multifocally thickened and contrast enhancing, indicating ventriculitis. There was mild multifocal asymmetric enhancement of the meninges of the left rostroventral calvarial margin and cervical spinal cord, with cervical syringomyelia. The patient was not able to self‐ventilate and was euthanased within 24 hours of starting supportive treatment. Necropsy findings were consistent with ventriculitis, meningitis, hydrocephalus and cerebellar herniation. A moderate yield of Pseudomonas aeruginosa was detected on cerebrospinal fluid culture and postmortem brain tissue culture.

Isoniazid-Induced Cerebellitis in a Chronic Kidney Disease Patient

Abstract The bacterial disease tuberculosis (TB), when it affects organs of the body other than the lungs, is called extrapulmonary TB. The treatment regimen includes the drugs isoniazid, rifampicin, pyrazinamide, and ethambutol, of which isoniazid is known to be the most active drug. Adverse drug reactions commonly include immunological as well as drug toxicity effects, with the latter being particularly important in renally impaired patients because of high risk of drug accumulation. Cerebellitis, which is an inflammatory condition that results in cerebellar dysfunction, is a rare complication of isoniazid use. Diagnosis is made after excluding all other possibilities. In the case described here, the extrapulmonary TB patient was a known case of chronic kidney disease (G4). He presented with slurred speech and sedation; magnetic resonance imaging scan showed bilateral fluid-attenuated inversion recovery hyperintensities in the dentate nuclei, indicative of cerebellitis. Dramatic improvement was seen upon replacing Isoniazid with levofloxacin and administration of antioxidants and pyridoxine supplements, which confirmed the diagnosis of isoniazid-induced cerebellitis.

Lateral Transorbital Endoscope-Assisted Resection of Anterior Temporal Lobe Neoplasm: 2-Dimensional Operative Video.

Transorbital neuroendoscopic surgery (TONES) is a minimally invasive approach, providing excellent access to extradural pathology of the sphenoid wing, orbital apex, Meckel's cave, and lateral cavernous sinus.1-10 Few cases of intradural pathology, such as gliomas or epileptic foci of the temporal lobe, have been described, apart from cadaveric anatomic studies.11-13 In this video, we present the case of a 63-year-old man with first time seizure. MRI demonstrated a fluid-attenuated inversion recovery hyperintense, noncontrast enhancing medial temporal lobe lesion consistent with low grade glioma. While frontotemporal craniotomy is the standard approach for this lesion, the TONES approach detailed in the video (the patient consented to the procedure and to the publication of his image) provided excellent access to the lesion, which minimized unnecessary trauma or removal of the lateral temporal lobe during the approach.4,14,15 The dura was closed primarily, overlayed with abdominal fat and fibrin glue, and a lumbar drain was left in place for 24 hours. The TONES approach avoided not only temporal lobe violation but also temporalis muscle disruption and any sort of external bone manipulation, which expedited the patient's recovery.16 The patient's eyelid incision was barely visible as early as postoperative day 7 with minimal ecchymosis. Postoperative MRI demonstrated a gross total resection. Pathology was consistent with a central nervous system World Health Organization grade 1 dysembryoplastic neuroepithelial tumor, a low-grade lesion with low risk of recurrence.17,18.

Comparison of MRI findings of hypothalamic-optic chiasmatic gliomas and craniopharyngiomas.

Differential diagnosis of hypothalamic-optic chiasmatic gliomas (HOCGs) and craniopharyngiomas on magnetic resonance imaging (MRI) can be quite challenging. To compare the MRI features of HOCGs and cranipharyngiomas. Patients diagnosed with HOCG or craniopharyngioma in histopathological evaluation between 2012 and 2022 and who underwent preoperative contrast-enhanced brain MRI were included. Various MRI features were retrospectively evaluated for each lesion: T2-weighted imaging and fluid attenuation inversion recovery hyperintensity, calcification, cystic change, T1-weighted (T1W) imaging hyperintensity of the cystic component, hemorrhage, involvement of sellar, suprasellar or other adjacent structures, lobulated appearance, presence of hydrocephalus, and contrast enhancement pattern. Apparent diffusion coefficient (ADC) values were also evaluated and compared. Among 38 patients included, 13 (34%) had HOCG and 25 (66%) had craniopharyngioma. Craniopharyngiomas had a significantly higher rate of cystic changes, calcification, and T1W imaging hyperintensity of the cystic component than HOCGs (P <0.05). Of HOCGs, 92% had chiasm involvement, 23% had optic nerve involvement, and 31% had brain stem involvement. On the other hand, chiasm involvement was observed in 8% of craniopharyngiomas, but none had optic nerve and/or brain stem involvement (P <0.05). While 62% (8/13) of HOCGs had diffuse homogeneous enhancement, 80% (20/25) of craniopharyngiomas had a diffuse heterogeneous enhancement pattern. Mean ADC values were significantly higher in craniopharyngiomas compared to HOCGs (2.1 vs. 1.6 ×10-3mm2/s, P <0.05). Although some neuroimaging findings may overlap, features such as presence of cyst and calcification, brain stem and optic pathway involvement, different enhancement patterns, and ADC values may be helpful in the differential diagnosis of HOCGs and craniopharyngiomas.

Circulating extracellular vesicles as biomarker for diagnosis, prognosis, and monitoring in glioblastoma patients.

Extracellular vesicles (EVs) obtained by noninvasive liquid biopsy from patient blood can serve as biomarkers. Here, we investigated the potential of circulating plasma EVs to serve as an indicator in the diagnosis, prognosis, and treatment response of glioblastoma patients. Plasma samples were collected from glioblastoma patients at multiple timepoints before and after surgery. EV concentrations were measured by nanoparticle tracking analysis and imaging flow cytometry. Tumor burden and edema were quantified by 3D reconstruction. EVs and tumors were further monitored in glioma-bearing mice. Glioblastoma patients displayed a 5.5-fold increase in circulating EVs compared to healthy donors (P < .0001). Patients with higher EV levels had significantly shorter overall survival and progression-free survival than patients with lower levels, and the plasma EV concentration was an independent prognostic parameter for overall survival. EV levels correlated with the extent of peritumoral fluid-attenuated inversion recovery hyperintensity but not with the size of the contrast-enhancing tumor, and similar findings were obtained in mice. Postoperatively, EV concentrations decreased rapidly back to normal levels, and the magnitude of the decline was associated with the extent of tumor resection. EV levels remained low during stable disease, but increased again upon tumor recurrence. In some patients, EV resurgence preceded the magnetic resonance imaging detectability of tumor relapse. Our findings suggest that leakiness of the blood-brain barrier may primarily be responsible for the high circulating EV concentrations in glioblastoma patients. Elevated EVs reflect tumor presence, and their quantification may thus be valuable in assessing disease activity.

Neuroinvasive West Nile Virus Infection in Immunosuppressed and Immunocompetent Adults

West Nile virus (WNV) is the leading cause of human arboviral disease in the US, peaking during summer. The incidence of WNV, including its neuroinvasive form (NWNV), is increasing, largely due to the expanding distribution of its vector, the Culex mosquito, and climatic changes causing heavy monsoon rains. However, the distinct characteristics and outcomes of NWNV in individuals who are immunosuppressed (IS) and individuals who are not IS remain underexplored. To describe and compare clinical and radiographic features, treatment responses, and outcomes of NWNV infection in individuals who are IS and those who are not IS. This retrospective cohort study used data from the Mayo Clinic Hospital system collected from July 2006 to December 2021. Participants were adult patients (age ≥18 years) with established diagnosis of NWNV infection. Data were analyzed from May 12, 2020, to July 20, 2023. Immunosuppresion. Outcomes of interest were clinical and radiographic features and 90-day mortality among patients with and without IS. Of 115 participants with NWNV infection (mean [SD] age, 64 [16] years; 75 [66%] male) enrolled, 72 (63%) were not IS and 43 (37%) were IS. Neurologic manifestations were meningoencephalitis (98 patients [85%]), encephalitis (10 patients [9%]), and myeloradiculitis (7 patients [6%]). Patients without IS, compared with those with IS, more frequently reported headache (45 patients [63%] vs 18 patients [42%]) and myalgias (32 patients [44%] vs 9 patients [21%]). In contrast, patients with IS, compared with those without, had higher rates of altered mental status (33 patients [77%] vs 41 patients [57%]) and myoclonus (8 patients [19%] vs 8 patients [4%]). Magnetic resonance imaging revealed more frequent thalamic T2 fluid-attenuated inversion recovery hyperintensities in individuals with IS than those without (4 patients [11%] vs 0 patients). Individuals with IS had more severe disease requiring higher rates of intensive care unit admission (26 patients [61%] vs 24 patients [33%]) and mechanical ventilation (24 patients [56%] vs 22 patients [31%]). The 90-day all-cause mortality rate was higher in the patients with IS compared with patients without IS (12 patients [28%] vs 5 patients [7%]), and this difference in mortality persisted after adjusting for Glasgow Coma Scale score (adjusted hazard ratio, 2.22; 95% CI, 1.07-4.27; P = .03). Individuals with IS were more likely to receive intravenous immunoglobulin than individuals without IS (12 individuals [17%] vs 24 individuals [56%]), but its use was not associated with survival (hazard ratio, 1.24; 95% CI, 0.50-3.09; P = .64). In this cohort study of individuals with NWNV infection, individuals with IS had a higher risk of disease complications and poor outcomes than individuals without IS, highlighting the need for innovative and effective therapies to improve outcomes in this high-risk population.

Magnetic Resonance Imaging Characteristics of LGI1-Antibody and CASPR2-Antibody Encephalitis

Rapid and accurate diagnosis of autoimmune encephalitis encourages prompt initiation of immunotherapy toward improved patient outcomes. However, clinical features alone may not sufficiently narrow the differential diagnosis, and awaiting autoantibody results can delay immunotherapy. To identify simple magnetic resonance imaging (MRI) characteristics that accurately distinguish 2 common forms of autoimmune encephalitis, LGI1- and CASPR2-antibody encephalitis (LGI1/CASPR2-Ab-E), from 2 major differential diagnoses, viral encephalitis (VE) and Creutzfeldt-Jakob disease (CJD). This cross-sectional study involved a retrospective, blinded analysis of the first available brain MRIs (taken 2000-2022) from 192 patients at Oxford University Hospitals in the UK and Mayo Clinic in the US. These patients had LGI1/CASPR2-Ab-E, VE, or CJD as evaluated by 2 neuroradiologists (discovery cohort; n = 87); findings were validated in an independent cohort by 3 neurologists (n = 105). Groups were statistically compared with contingency tables. Data were analyzed in 2023. MRI findings including T2 or fluid-attenuated inversion recovery (FLAIR) hyperintensities, swelling or volume loss, presence of gadolinium contrast enhancement, and diffusion-weighted imaging changes. Correlations with clinical features. Among 192 participants with MRIs reviewed, 71 were female (37%) and 121 were male (63%); the median age was 66 years (range, 19-92 years). By comparison with VE and CJD, in LGI1/CASPR2-Ab-E, T2 and/or FLAIR hyperintensities were less likely to extend outside the temporal lobe (3/42 patients [7%] vs 17/18 patients [94%] with VE; P < .001, and 3/4 patients [75%] with CJD; P = .005), less frequently exhibited swelling (12/55 [22%] with LGI1/CASPR2-Ab-E vs 13/22 [59%] with VE; P = .003), and showed no diffusion restriction (0 patients vs 16/22 [73%] with VE and 8/10 [80%] with CJD; both P < .001) and rare contrast enhancement (1/20 [5%] vs 7/17 [41%] with VE; P = .01). These findings were validated in an independent cohort and generated an area under the curve of 0.97, sensitivity of 90%, and specificity of 95% among cases with T2/FLAIR hyperintensity in the hippocampus and/or amygdala. In this study, T2 and/or FLAIR hyperintensities confined to the temporal lobes, without diffusion restriction or contrast enhancement, robustly distinguished LGI1/CASPR2-Ab-E from key differential diagnoses. These observations should assist clinical decision-making toward expediting immunotherapy. Their generalizability to other forms of autoimmune encephalitis and VE should be examined in future studies.

Comparison of standing cone‐beam computed tomography and low‐field magnetic resonance imaging findings in the equine metacarpo‐ or metatarsophalangeal region of standing sedated horses

SummaryBackgroundCone‐beam computed tomography (CBCT) and low‐field magnetic resonance imaging (MRI) are increasingly used in standing horses, so it is important to understand an efficient application of these imaging modalities.ObjectiveTo compare CBCT and MRI findings in the metacarpo (MCP)/metatarsophalangeal (MTP) region of clinical patients imaged for diagnostic purposes.Study designRetrospective study.MethodsThe CBCT and MRI images of the MCP/MTP region from equine clinical patients undergoing both standing MRI and CBCT imaging for lameness localised to the fetlock region (2021–2023) were retrospectively reviewed. Presence, location and imaging features of lesions were compared between modalities using descriptive analysis.ResultsImaging studies of 24 MCP/MTP regions from 22 horses were included. CBCT provided the assessment of subchondral bone integrity in palmar/plantar osteochondral disease, details of the length and associated attenuation changes of third metacarpal/tarsal parasagittal groove and proximal phalanx sagittal groove fissures, structural integrity and attenuation changes of subchondral and trabecular bone injuries, proximal phalanx dorsoproximal defects and anatomical and structural details of proximal sesamoid bone injuries. MRI provided the evaluation of short tau inversion recovery (STIR) hyperintensity associated with bone lesions and the extent of increased fluid accumulation in bone. CBCT revealed reduced joint space, indicating articular cartilage loss, while MRI showed joint distension and synovitis. MRI revealed generalised osseous STIR hyperintensity associated with septic arthritis. Soft tissue injuries were most identified by MRI except for heterotopic mineralisation most detected by CBCT.Main limitationsImaging findings not verified by a gold standard.ConclusionsCBCT and MRI contributed different diagnostic information so optimal information was obtained by using both modalities. Standing CBCT showed changes in bone structure and attenuation but was limited in detecting soft tissue injuries. Standing MRI showed increased fluid accumulation in bone and soft tissue injuries but was limited in assessing structural details of bone injuries.

OPHTHALMOLOGIC MANIFESTATIONS REVEALING POSTERIOR REVERSIBLE ENCEPHALOPATHY SYNDROME: A CASE REPORT

Posterior reversible encephalopathy syndrome (PRES) is a rare clinico-radiological syndrome, secondary to many diseases especially high blood pressure. First described by Hinchey in 1996, pathophysiology is not clear. Clinical manifestations are headache, seizures, altered mental state such as confusion or coma, and also visual disturbances, such as hemianopia, blurred vision, diplopia, or cortical blindness. We report the case of a Moroccan 47-years old patient who arrived at the ophthalmology emergency presenting a sudden vision loss and horizontal diplopia, associated with headache. General examination found a high blood pressure at 240/110mmhg. The funduscopy of both eyes found hypertensive retinopathy. A brain MRI was realized showing bilateral occipital cortex T2/fluid-attenuated inversion recovery (FLAIR) hyperintensities. The diagnosis of Posterior reversible encephalopathy syndrome was retained.

Reversible sulcal fluid-attenuated inversion recovery hyperintensity after combined bypass surgery for moyamoya disease - A "crevasse" sign.

Transient fluid-attenuated inversion recovery (FLAIR) hyperintensity is often observed on the operated brain surface after direct or combined bypass surgery for moyamoya disease, but its pathophysiology and clinical significance are still obscure. This study was aimed to clarify the underlying mechanism and clinical significance. This prospective study included 106 hemispheres of 61 patients with moyamoya disease and analyzed their radiological findings before and after combined bypass surgery. This study also included 11 patients who underwent superficial temporal artery to middle cerebral artery anastomosis for occlusive carotid artery diseases as the controls. Magnetic resonance imaging examination was serially repeated, and cerebral blood flow was measured before and after surgery. Signal intensity ratio (SIR) in the cortical sulci and cortex to the adjacent white matter on FLAIR images was calculated, and the postoperative SIR changes were semi-quantitatively evaluated to assess the temporal profile of postoperative FLAIR hyperintensity. Postoperative FLAIR hyperintensity occurred within the cortical sulci on the operated hemispheres in all moyamoya patients but not in patients with occlusive carotid artery diseases. SIR values started to increase immediately after surgery, peaked at about 4-fold at 4-13 days post-surgery, then declined, and recovered to baseline values over 28 days or later. The magnitude of this phenomenon was proportional to the severity of cerebral ischemia but not to postoperative hyperperfusion. Reversible sulcal FLAIR hyperintensity specifically occurs in the operated hemispheres after direct bypass surgery for moyamoya disease. This "crevasse sign" may represent the mixture of the extensive leakage of oxygen and proteins from the pial arteries into the CSF.

Creutzfeldt-Jakob disease presenting as psychiatric disorder: case presentation and systematic review.

Creutzfeldt-Jakob disease (CJD) is a spongiform encephalopathy caused by misfolded human prion proteins (PrP)s. Due to variability in presentation, the diagnosis may be missed in lieu of various psychiatric disorders. Our study reports on a prototypical case and psychiatric mimic for CJD, and the workup used to establish the correct diagnosis. A 54-year-old male with a past medical history of traumatic brain injury and major depressive disorder presented with chest pain. During the hospital stay, he was found to be increasingly aggressive, and behaved out of character. Further review of clinical history revealed that the patient was diagnosed with cognitive impairment and depression one year prior. The patient was agitated, poorly redirectable, and had unstable gait on neurological examination. Magnetic resonance imaging (MRI) of the brain demonstrated restricted diffusion (DWI) along the parietooccipital and temporal regions (L > R) and in the subcortical structures, including the basal ganglia and thalami, with accompanying subtle fluid attenuation inversion recovery (FLAIR) hyperintense signal abnormality in these regions, deemed as artifactual at the time. Repeat MRI brain two months later demonstrated progression of the DWI signal with ADC correlate and FLAIR findings. Cerebrospinal fluid 14-3-3 and RT-QuIC samples were positive. Upon passing a few months later, brain autopsy and Western Blot confirmed the CJD diagnosis. Literature review was conducted on PubMed to identify CJD cases initially diagnosed as psychiatric disorder. Search terms included "CJD" or "Creutzfeldt-Jakob disease" with three common psychiatric diagnoses, "Depression," "Psychosis," and "Mania." Positive EEG, MRI, PET, and CSF (including protein 14-3-3 and tau) findings for CJD were found in 66.7, 81.1, 50, and 72.7% of cases, respectively. Overall, CJD can present as a psychiatric mimic. In suspicious cases, EEG, imaging, and CSF studies should be promptly utilized to arrive at the correct diagnosis. Repeated MRI imaging is often required to help in the diagnostic process. Brain biopsy should be considered in selected cases.