0000000000749635

AUTHOR

Stephanie Njau

showing 2 related works from this author

Denoising of MR spectroscopy signals using total variation and iterative Gauss-Seidel gradient updates

2015

We present a fast variational approach for denoising signals from magnetic resonance spectroscopy (MRS). Differently from the TV approaches applied to denoising of images, this is the first time to our knowledge that it has been used for the processing of free induction decay signals from single-voxel spectroscopy (SVS) acquisitions. Another novelty in this study is the direct use of the Euler Lagrange formulation coupled with Gauss Seidel gradient updates to improve the speed of iteration and reduce ringing. Results from brain MRS signals show improvement in signal to noise ratio as well as reduction in estimation error in the quantification of metabolites.

Free induction decayReduction (complexity)Mathematical optimizationSignal-to-noise ratioNoise reductionGauss–Seidel methodRingingTotal variation denoisingSpectroscopyAlgorithmMathematics2015 IEEE 12th International Symposium on Biomedical Imaging (ISBI)
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Neurochemical correlates of rapid treatment response to electroconvulsive therapy in patients with major depression

2016

Background: Electroconvulsive therapy (ECT) is a highly effective brain stimulation treatment for severe depression. Identifying neurochemical changes linked with ECT may point to biomarkers and predictors of successful treatment response. Methods: We used proton magnetic resonance spectroscopy (1H-MRS) to measure longitudinal changes in glutamate/glutamine (Glx), creatine (Cre), choline (Cho) and N-acetylaspartate (NAA) in the dorsal (dACC) and subgenual anterior cingulate cortex (sgACC) and bilateral hippocampus in patients receiving ECT scanned at baseline, after the second ECT session and after the ECT treatment series. Patients were compared with demographically similar controls at bas…

MaleBipolar Disordermedicine.medical_treatmentProton Magnetic Resonance SpectroscopyHippocampusHippocampuschemistry.chemical_compound0302 clinical medicineElectroconvulsive therapyMedicineCholinePharmacology (medical)Longitudinal StudiesElectroconvulsive TherapyDepression (differential diagnoses)PsychiatryDepressionPsychiatry and Mental healthmedicine.anatomical_structureMental HealthTreatment OutcomeCardiologyRegression AnalysisCognitive SciencesFemaleClinical psychologyResearch PaperAdultmedicine.medical_specialtyClinical SciencesCreatinebehavioral disciplines and activitiesGyrus Cinguli03 medical and health sciencesNeurochemicalClinical ResearchInternal medicinemental disordersHumansBiological PsychiatryAnterior cingulate cortexPsychiatric Status Rating ScalesDepressive DisorderDepressive Disorder Majorbusiness.industryNeurosciencesMajor030227 psychiatryBrain DisordersCross-Sectional Studiesnervous systemchemistryBrain stimulationbusiness030217 neurology & neurosurgeryBiomarkersFollow-Up Studies
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