Publications by authors named "Alexander U Brandt"

Quantitative magnetic resonance imaging (qMRI) involves mapping microstructure in standardized units sensitive to histological properties and supplements conventional MRI, which relies on contrast weighted images where intensities have no biophysical meaning. While measuring tissue properties such as myelin, iron or water content is desired in a disease context, qMRI changes may typically reflect mixed influences from aging or pre-clinical degeneration. We used a fast multi-parameter mapping (MPM) protocol for clinical routine at 3T to reconstruct whole-brain quantitative maps of magnetization transfer saturation (MT), proton density (PD), longitudinal (R1), and transverse relaxation rate (R2*) with 1.

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  • Patients with neuromyelitis optica spectrum disorder (NMOSD) often have antibodies against aquaporin-4 (AQP4), making MRI monitoring critical for understanding the disease's progression.
  • A retrospective study involved MRI data from 525 AQP4-IgG-seropositive NMOSD patients across 11 countries, focusing on the types and locations of lesions in the central nervous system.
  • Results showed a high prevalence of hyperintense lesions in the brain and significant patterns of myelitis in the spinal cord, emphasizing the importance of MRI in tracking this condition.
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  • The 2022 International Consortium for Optic Neuritis introduced new diagnostic criteria using optical coherence tomography (OCT) to better assess optic neuritis, with a particular focus on intereye difference metrics in patients with MOG-associated optic neuritis (MOG-ON).
  • A multi-center study validated the diagnostic value of pre-established intereye difference cutoff values in 66 subjects, finding that metrics from the macular ganglion cell and inner plexiform layer (mGCIP) were most sensitive and specific for diagnosing MOG-ON.
  • Results indicated that OCT-based intereye difference metrics had high diagnostic accuracy for MOG-ON, especially in cases of unilateral optic neuritis, suggesting these metrics could effectively distinguish affected individuals
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  • The study aimed to describe the clinical features of double-antibody seronegative neuromyelitis optica spectrum disorders (DN-NMOSD), focusing on how these disorders affect the retina.
  • Researchers analyzed data from 25 individuals with DN-NMOSD and compared it to those with aquaporin-4 antibody positive neuromyelitis optica (AQP4-NMOSD) and healthy controls, using optical coherence tomography (OCT) to assess retinal damage.
  • The findings revealed significant thinning of the retinal nerve fiber layer and ganglion cell layers in DN-NMOSD patients, even after just one optic neuritis episode, indicating severe retinal damage and neurodegeneration regardless of an ON history.
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  • The study aims to evaluate how age-adjusted scores from retinal optical coherence tomography (OCT) can predict future disease activity and disability worsening in people with multiple sclerosis (PwMS).
  • Researchers created age-adjusted reference values for specific retinal measurements using data from healthy eyes and transformed existing data from PwMS into these scores for comparison.
  • Results showed that lower scores (pRNFL-z) were linked to a greater risk of disability worsening, with significant findings from two different cohorts highlighting the importance of retinal imaging in assessing MS progression.
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  • Retinal optical coherence tomography (OCT) serves as a biomarker for tracking disease progression in relapsing-remitting multiple sclerosis (RRMS), although the changes in retinal layers for progressive MS remain uncertain.
  • Analyzing data from 195 RRMS, 87 secondary progressive MS (SPMS), 125 primary progressive MS (PPMS), and 98 control patients, researchers found that certain retinal layer thicknesses could predict relapses and MRI activity in various MS types.
  • However, the variability in measuring retinal thickness limits the effectiveness of longitudinal assessments for individual patients.
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Complex diseases such as Multiple Sclerosis (MS) cover a wide range of biological scales, from genes and proteins to cells and tissues, up to the full organism. In fact, any phenotype for an organism is dictated by the interplay among these scales. We conducted a multilayer network analysis and deep phenotyping with multi-omics data (genomics, phosphoproteomics and cytomics), brain and retinal imaging, and clinical data, obtained from a multicenter prospective cohort of 328 patients and 90 healthy controls.

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Objective: Retrograde trans-synaptic neuroaxonal degeneration is considered a key pathological factor of subclinical retinal neuroaxonal damage in multiple sclerosis (MS). We aim to evaluate the longitudinal association of optic radiation (OR) lesion activity with retinal neuroaxonal damage and its role in correlations between retinal and brain atrophy in people with clinically isolated syndrome and early MS (pweMS).

Methods: Eighty-five pweMS were retrospectively screened from a prospective cohort (Berlin CIS cohort).

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This study aimed to identify quantitative biomarkers of motor function for cerebellar ataxia by evaluating gait and postural control using an RGB-depth camera-based motion analysis system. In 28 patients with degenerative cerebellar ataxia and 33 age- and sex-matched healthy controls, motor tasks (short-distance walk, closed feet stance, and stepping in place) were selected from a previously reported protocol, and scanned using Kinect V2 and customized software. The Clinical Assessment Scale for the Assessment and Rating of Ataxia (SARA) was also evaluated.

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Background: In the demyelinating disease multiple sclerosis (MS), chronic-active brain inflammation, remyelination failure and neurodegeneration remain major issues despite immunotherapy. While B cell depletion and blockade/sequestration of T and B cells potently reduces episodic relapses, they act peripherally to allow persistence of chronic-active brain inflammation and progressive neurological dysfunction. N-acetyglucosamine (GlcNAc) is a triple modulator of inflammation, myelination and neurodegeneration.

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Background: Functional connectome fingerprinting can identify individuals based on their functional connectome. Previous studies relied mostly on short intervals between fMRI acquisitions.

Objective: This cohort study aimed to determine the stability of connectome-based identification and their underlying signatures in patients with multiple sclerosis and healthy individuals with long follow-up intervals.

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  • Multiple sclerosis (MS) is a chronic inflammatory disease affecting the central nervous system, and optical coherence tomography (OCT) is emerging as a noninvasive method to monitor it, utilizing AI for detailed analysis.
  • The study employs advanced techniques, like multilayer segmented OCTs, to distinguish between MS patients and healthy controls, using algorithms like support vector machine and random forest for classification validation.
  • The results highlight that the ganglion cell and inner nuclear layers of the retina are crucial in differentiating MS from healthy individuals, achieving an accuracy of 88% with the linear SVM model.
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Background And Objectives: With the increasing use of visually evoked potentials (VEPs) as quantitative outcome parameters for myelin in clinical trials, an in-depth understanding of longitudinal VEP latency changes and their prognostic potential for subsequent neuronal loss will be required. In this longitudinal multicenter study, we evaluated the association and prognostic potential of VEP latency for retinal neurodegeneration, measured by optical coherence tomography (OCT), in relapsing-remitting MS (RRMS).

Methods: We included 293 eyes of 147 patients with RRMS (age [years, median ± SD] 36 ± 10, male sex 35%, F/U [years, median {IQR} 2.

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  • The study investigates the effectiveness of intereye differences (IED) in optical coherence tomography (OCT) parameters to diagnose optic neuritis (ON) in patients with aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorders (AQP4+NMOSD).
  • It compares OCT data from AQP4+NMOSD patients who had unilateral ON more than six months prior with healthy controls and other AQP4+NMOSD patients without ON, measuring both absolute and percentage differences in retinal thickness.
  • The findings show high accuracy for using IED metrics in diagnosing ON in AQP4+NMOSD, indicating that these OCT parameters could improve diagnostic criteria for this condition.
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  • MOG antibodies are linked to specific types of CNS demyelinating syndromes that differ from multiple sclerosis and aquaporin-4-seropositive neuromyelitis optica spectrum disorder.* -
  • A proposed set of diagnostic criteria for MOG antibody-associated disease (MOGAD) emphasizes that the presence of MOG-IgG is crucial and typically associates with conditions like acute disseminated encephalomyelitis, optic neuritis, or transverse myelitis.* -
  • Validating these criteria could enhance the diagnosis of MOGAD, which is important for understanding long-term clinical outcomes and for refining clinical trial criteria, though not all multiple sclerosis patients need to be tested for MOG-IgG.*
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Background And Purpose: Thinning of the retinal combined ganglion cell and inner plexiform layer (GCIP) as measured by optical coherence tomography (OCT) is a common finding in patients with multiple sclerosis. This study aimed to investigate whether a single retinal OCT analysis allows prediction of future disease activity after a first demyelinating event.

Methods: This observational cohort study included 201 patients with recently diagnosed clinically isolated syndrome or relapsing-remitting multiple sclerosis from two German tertiary referral centers.

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Background: Retinal degeneration leading to optical coherence tomography (OCT) changes is frequent in patients with multiple sclerosis (PwMS).

Objective: To investigate associations among OCT changes, MRI measurements of global and regional brain volume loss, and physical and cognitive impairment in PwMS.

Methods: 95 PwMS and 52 healthy controls underwent OCT and MRI examinations.

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Background: Large-scale disease overarching longitudinal data are rare in the field of neuroimmunology. However, such data could aid early disease stratification, understanding disease etiology and ultimately improve treatment decisions. The Berlin Registry of Neuroimmunological Entities (BERLimmun) is a longitudinal prospective observational study, which aims to identify diagnostic, disease activity and prognostic markers and to elucidate the underlying pathobiology of neuroimmunological diseases.

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Background: The diagnosis of multiple sclerosis (MS) requires demyelinating events that are disseminated in time and space. Peripapillary retinal nerve fiber layer (pRNFL) thickness as measured by optical coherence tomography (OCT) distinguishes eyes with a prior history of acute optic neuritis (ON) and may provide evidence to support a demyelinating attack.

Objective: To investigate whether a deep learning (DL)-based network can distinguish between eyes with prior ON and healthy control (HC) eyes using peripapillary ring scans.

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Optic neuritis (ON) in neuromyelitis optica spectrum disorders (NMOSD) regularly leads to more profound vision loss compared to multiple sclerosis (MS) and myelin-oligodendrocyte-glycoprotein-antibody associated disease (MOGAD). Here we investigate ON-related vision loss in NMOSD compared to MS and MOGAD in order to identify neuroaxonal and retinal contributors to visual dysfunction. In this retrospective study we included patients with aquaporin-4-antibody seropositive NMOSD (n = 28), MOGAD (n = 14), MS (n = 29) and controls (n = 14).

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Background: Aquaporin-4 immunoglobulin-G positive (AQP4-IgG) neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune astrocytopathy associated with optic neuritis (ON). Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an oligodendrocytopathy with a similar phenotype. Serum glial fibrillary acidic protein (sGFAP), an astrocyte-derived protein, is associated with disease severity in AQP4-IgG NMOSD.

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Background: Spectral-domain (SD-) optical coherence tomography (OCT) can reliably measure axonal (peripapillary retinal nerve fiber layer [pRNFL]) and neuronal (macular ganglion cell + inner plexiform layer [GCIPL]) thinning in the retina. Measurements from 2 commonly used SD-OCT devices are often pooled together in multiple sclerosis (MS) studies and clinical trials despite software and segmentation algorithm differences; however, individual pRNFL and GCIPL thickness measurements are not interchangeable between devices. In some circumstances, such as in the absence of a consistent OCT segmentation algorithm across platforms, a conversion equation to transform measurements between devices may be useful to facilitate pooling of data.

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Purpose: To test the hypothesis that newly developed shape measures using optical coherence tomography (OCT) macular volume scans can discriminate patients with perimetric glaucoma from healthy subjects.

Methods: OCT structural measures defining macular topography and volume were recently developed based on cubic Bézier curves. We exported macular volume scans from 135 eyes with glaucoma (133 patients) and 155 healthy eyes (85 subjects) and estimated global and quadrant-based measures.

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Background And Objectives: Connectivity-based approaches incorporating the distribution and magnitude of the extended brain network aberrations caused by lesions may offer higher sensitivity for axonal damage in patients with multiple sclerosis (MS) than conventional lesion characteristics. Using individual brain disconnectome mapping, we tested the longitudinal associations between putative imaging-based brain network aberrations and levels of serum neurofilament light chain (NfL) as a neuroaxonal injury biomarker.

Methods: MS patients (n = 312, mean age 42.

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