title: Assessment of brain cognitive functions in patients with vitamin B12 deficiency using resting state functional MRI: A longitudinal study.
abstract: BACKGROUND
  The resting state functional MRI (rsfMRI) approach is useful to explore the brain's functional organization in health and disease conditions. In this study, using rsfMRI the alteration in brain due to vitamin B12 deficiency and reversibility of these alterations following therapy was studied.
  
  
  METHODS
  Thirteen patients with clinical and biochemical evidence of vitamin B12 deficiency were recruited in this study. Fifteen age and sex matched healthy controls were also included. Patients and controls were clinically evaluated using neuropsychological test (NPT). The analysis was carried out using regional homogeneity (ReHo) and low frequency oscillations (LFO) of BOLD signals in resting state. Six patients were also evaluated with rsfMRI and NPT after 6 weeks replacement therapy.
  
  
  RESULTS
  ReHo values in patients with vitamin B12 deficiency were significantly lower than controls in the entire cerebrum and the brain networks associated with cognition control, i.e., default mode, cingulo-opercular and fronto-parietal network. There was no significant difference using LFO and it did not show significant correlations with NPT scores. ReHo showed significant correlation with NPT scores. All the 6 patients showed increase in ReHo after replacement therapy.
  
  
  CONCLUSIONS
  We conclude that brain networks associated with cognition control are altered in patients with vitamin B12 deficiency, which partially recover following six weeks of replacement therapy. This is the first study to evaluate the rsfMRI in the light of clinical neuropsychological evaluation in patients. rsfMRI may be used as functional biomarker to assess therapeutic response in vitamin B12 deficiency patients.
authors.affiliation: Philips India Ltd., Bangalore, India.
authors.forename: Lalit
authors.initials: L
authors.lastname: Gupta
authors.affiliation: Department of Radiology and Imaging, Fortis Memorial Research Institute, Gurgaon, Haryana, India. Electronic address: rakeshree1@gmail.com.
authors.forename: Rakesh Kumar
authors.initials: RK
authors.lastname: Gupta
authors.affiliation: Department of Radiology and Imaging, Fortis Memorial Research Institute, Gurgaon, Haryana, India.
authors.forename: Pradeep K
authors.initials: PK
authors.lastname: Gupta
authors.affiliation: Department of Neurology, King George Medical University, Lucknow, India.
authors.forename: Hardeep Singh
authors.initials: HS
authors.lastname: Malhotra
authors.affiliation: Philips India Ltd., Gurgaon, India.
authors.forename: Indrajit
authors.initials: I
authors.lastname: Saha
authors.affiliation: Department of Neurology, King George Medical University, Lucknow, India.
authors.forename: Ravindra K
authors.initials: RK
authors.lastname: Garg
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000473:pathology / Q000503:physiopathology; D015203:Reproducibility of Results; D012146:Rest; D012680:Sensitivity and Specificity; D014806:Vitamin B 12 Deficiency / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D055815:Young Adult
keywords: Brain cognitive networks; Neuropsychological test; Regional homogeneity; Resting-state fMRI; Vitamin B12 deficiency