Research Overview

Dr. Vajapeyam's research interests are in the areas of MR image and data processing, with special emphasis on brain tumors and diffusion. His research goals include: Developing image and data analysis methods for magnetic resonance imaging and magnetic resonance spectroscopy Studying white matter development of the human brain in infancy and childhood Diffusion tensor imaging and tractography in the human brain Applications of magnetic resonance methods for the characterization, assessment and treatment of human brain neoplasms 

About Sridhar Vajapeyam, PhD 

Dr. Vajapeyam did his undergraduate work in mechanical engineering at the Indian Institute of Technology in Madras, India. He earned his ME and PhD degrees in mechanical engineering from the University of Delaware and completed a 3-year postdoctoral fellowship at Children’s Hospital Boston in 1997.

Researcher Services

Researcher Areas

  • MR Image and Data Processing
  • Brain Tumors and Diffusion

Research Departments

PUBLICATIONS

Publications powered by Harvard Catalyst Profiles

  1. Vajapeyam S, Ecklund K, Mulkern RV, Feldman HA, O'Donnell JM, DiVasta AD, Rosen CJ, Gordon CM. Magnetic resonance imaging and spectroscopy evidence of efficacy for adrenal and gonadal hormone replacement therapy in anorexia nervosa. Bone. 2018 05; 110:335-342. View abstract
  2. Vajapeyam S, Brown D, Johnston PR, Ricci KI, Kieran MW, Lidov HGW, Poussaint TY. Multiparametric Analysis of Permeability and ADC Histogram Metrics for Classification of Pediatric Brain Tumors by Tumor Grade. AJNR Am J Neuroradiol. 2018 Jan 04. View abstract
  3. Ecklund K, Vajapeyam S, Mulkern RV, Feldman HA, O'Donnell JM, DiVasta AD, Gordon CM. Bone marrow fat content in 70 adolescent girls with anorexia nervosa: Magnetic resonance imaging and magnetic resonance spectroscopy assessment. Pediatr Radiol. 2017 Jul; 47(8):952-962. View abstract
  4. Zukotynski KA, Vajapeyam S, Fahey FH, Kocak M, Brown D, Ricci KI, Onar-Thomas A, Fouladi M, Poussaint TY. Correlation of 18F-FDG PET and MRI Apparent Diffusion Coefficient Histogram Metrics with Survival in Diffuse Intrinsic Pontine Glioma: A Report from the Pediatric Brain Tumor Consortium. J Nucl Med. 2017 Aug; 58(8):1264-1269. View abstract
  5. Vajapeyam S, Stamoulis C, Ricci K, Kieran M, Poussaint TY. Automated Processing of Dynamic Contrast-Enhanced MRI: Correlation of Advanced Pharmacokinetic Metrics with Tumor Grade in Pediatric Brain Tumors. AJNR Am J Neuroradiol. 2017 Jan; 38(1):170-175. View abstract
  6. Poussaint TY, Vajapeyam S, Ricci KI, Panigrahy A, Kocak M, Kun LE, Boyett JM, Pollack IF, Fouladi M. Apparent diffusion coefficient histogram metrics correlate with survival in diffuse intrinsic pontine glioma: a report from the Pediatric Brain Tumor Consortium. Neuro Oncol. 2016 05; 18(5):725-34. View abstract
  7. Kieran MW, Chi S, Goldman S, Onar-Thomas A, Poussaint TY, Vajapeyam S, Fahey F, Wu S, Turner DC, Stewart CF, Moses M, Packer RJ, Jakacki R, Banerjee A, Boyett JM, Fouladi M, Kun L. A phase I trial and PK study of cediranib (AZD2171), an orally bioavailable pan-VEGFR inhibitor, in children with recurrent or refractory primary CNS tumors. Childs Nerv Syst. 2015 Sep; 31(9):1433-45. View abstract
  8. Mulkern RV, Ricci KI, Vajapeyam S, Chenevert TL, Malyarenko DI, Kocak M, Poussaint TY. Pediatric brain tumor consortium multisite assessment of apparent diffusion coefficient z-axis variation assessed with an ice-water phantom. Acad Radiol. 2015 Mar; 22(3):363-9. View abstract
  9. Rollins CK, Watson CG, Asaro LA, Wypij D, Vajapeyam S, Bellinger DC, DeMaso DR, Robertson RL, Newburger JW, Rivkin MJ. White matter microstructure and cognition in adolescents with congenital heart disease. J Pediatr. 2014 Nov; 165(5):936-44.e1-2. View abstract
  10. Zukotynski K, Fahey F, Kocak M, Kun L, Boyett J, Fouladi M, Vajapeyam S, Treves T, Poussaint TY. 18F-FDG PET and MR imaging associations across a spectrum of pediatric brain tumors: a report from the pediatric brain tumor consortium. J Nucl Med. 2014 Sep; 55(9):1473-80. View abstract
  11. Gururangan S, Fangusaro J, Poussaint TY, McLendon RE, Onar-Thomas A, Wu S, Packer RJ, Banerjee A, Gilbertson RJ, Fahey F, Vajapeyam S, Jakacki R, Gajjar A, Goldman S, Pollack IF, Friedman HS, Boyett JM, Fouladi M, Kun LE. Efficacy of bevacizumab plus irinotecan in children with recurrent low-grade gliomas--a Pediatric Brain Tumor Consortium study. Neuro Oncol. 2014 Jan; 16(2):310-7. View abstract
  12. Zukotynski KA, Fahey FH, Vajapeyam S, Ng SS, Kocak M, Gururangan S, Kun LE, Poussaint TY. Exploratory evaluation of MR permeability with 18F-FDG PET mapping in pediatric brain tumors: a report from the Pediatric Brain Tumor Consortium. J Nucl Med. 2013 Aug; 54(8):1237-43. View abstract
  13. Rivkin MJ, Watson CG, Scoppettuolo LA, Wypij D, Vajapeyam S, Bellinger DC, DeMaso DR, Robertson RL, Newburger JW. Adolescents with D-transposition of the great arteries repaired in early infancy demonstrate reduced white matter microstructure associated with clinical risk factors. J Thorac Cardiovasc Surg. 2013 Sep; 146(3):543-9.e1. View abstract
  14. Gururangan S, Fangusaro J, Young Poussaint T, Onar-Thomas A, Gilbertson RJ, Vajapeyam S, Gajjar A, Goldman S, Friedman HS, Packer RJ, Boyett JM, Kun LE, McLendon R. Lack of efficacy of bevacizumab + irinotecan in cases of pediatric recurrent ependymoma--a Pediatric Brain Tumor Consortium study. Neuro Oncol. 2012 Nov; 14(11):1404-12. View abstract
  15. Fleming BC, Vajapeyam S, Connolly SA, Magarian EM, Murray MM. The use of magnetic resonance imaging to predict ACL graft structural properties. J Biomech. 2011 Nov 10; 44(16):2843-6. View abstract
  16. Poussaint TY, Kocak M, Vajapeyam S, Packer RI, Robertson RL, Geyer R, Haas-Kogan D, Pollack IF, Vezina G, Zimmerman R, Cha S, Patay Z, Boyett JM, Kun LE. MRI as a central component of clinical trials analysis in brainstem glioma: a report from the Pediatric Brain Tumor Consortium (PBTC). Neuro Oncol. 2011 Apr; 13(4):417-27. View abstract
  17. Zukotynski KA, Fahey FH, Kocak M, Alavi A, Wong TZ, Treves ST, Shulkin BL, Haas-Kogan DA, Geyer JR, Vajapeyam S, Boyett JM, Kun LE, Poussaint TY. Evaluation of 18F-FDG PET and MRI associations in pediatric diffuse intrinsic brain stem glioma: a report from the Pediatric Brain Tumor Consortium. J Nucl Med. 2011 Feb; 52(2):188-95. View abstract
  18. Prabhu SP, Ng S, Vajapeyam S, Kieran MW, Pollack IF, Geyer R, Haas-Kogan D, Boyett JM, Kun L, Poussaint TY. DTI assessment of the brainstem white matter tracts in pediatric BSG before and after therapy: a report from the Pediatric Brain Tumor Consortium. Childs Nerv Syst. 2011 Jan; 27(1):11-8. View abstract
  19. Gururangan S, Chi SN, Young Poussaint T, Onar-Thomas A, Gilbertson RJ, Vajapeyam S, Friedman HS, Packer RJ, Rood BN, Boyett JM, Kun LE. Lack of efficacy of bevacizumab plus irinotecan in children with recurrent malignant glioma and diffuse brainstem glioma: a Pediatric Brain Tumor Consortium study. J Clin Oncol. 2010 Jun 20; 28(18):3069-75. View abstract
  20. Ecklund K, Vajapeyam S, Feldman HA, Buzney CD, Mulkern RV, Kleinman PK, Rosen CJ, Gordon CM. Bone marrow changes in adolescent girls with anorexia nervosa. J Bone Miner Res. 2010 Feb; 25(2):298-304. View abstract
  21. Schwartz R, Mulkern R, Vajapeyam S, Kacher DF. Catheter angiography, MR angiography, and MR perfusion in posterior reversible encephalopathy syndrome. AJNR Am J Neuroradiol. 2009 Feb; 30(2):E19; author reply E20. View abstract
  22. Poussaint TY, Phillips PC, Vajapeyam S, Fahey FH, Robertson RL, Osganian S, Ramamurthy U, Mulkern RV, Treves ST, Boyett JM, Kun LE. The Neuroimaging Center of the Pediatric Brain Tumor Consortium-collaborative neuroimaging in pediatric brain tumor research: a work in progress. AJNR Am J Neuroradiol. 2007 Apr; 28(4):603-7. View abstract
  23. Turner CD, Chi S, Marcus KJ, MacDonald T, Packer RJ, Poussaint TY, Vajapeyam S, Ullrich N, Goumnerova LC, Scott RM, Briody C, Chordas C, Zimmerman MA, Kieran MW. Phase II study of thalidomide and radiation in children with newly diagnosed brain stem gliomas and glioblastoma multiforme. J Neurooncol. 2007 Mar; 82(1):95-101. View abstract
  24. Mulkern RV, Vajapeyam S, Haker SJ, Maier SE. Magnetization transfer studies of the fast and slow tissue water diffusion components in the human brain. NMR Biomed. 2005 May; 18(3):186-94. View abstract
  25. Mulkern RV, Huang J, Vajapeyam S, Packard AB, Oshio K, Grinspoon S. Fat fractions and spectral T2 values in vertebral bone marrow in HIV- and non-HIV-infected men: a 1H spectroscopic imaging study. Magn Reson Med. 2004 Sep; 52(3):552-8. View abstract
  26. Rivkin MJ, Wolraich D, Als H, McAnulty G, Butler S, Conneman N, Fischer C, Vajapeyam S, Robertson RL, Mulkern RV. Prolonged T*2 values in newborn versus adult brain: Implications for fMRI studies of newborns. Magn Reson Med. 2004 Jun; 51(6):1287-91. View abstract
  27. Als H, Duffy FH, McAnulty GB, Rivkin MJ, Vajapeyam S, Mulkern RV, Warfield SK, Huppi PS, Butler SC, Conneman N, Fischer C, Eichenwald EC. Early experience alters brain function and structure. Pediatrics. 2004 Apr; 113(4):846-57. View abstract
  28. Maier SE, Vajapeyam S, Mamata H, Westin CF, Jolesz FA, Mulkern RV. Biexponential diffusion tensor analysis of human brain diffusion data. Magn Reson Med. 2004 Feb; 51(2):321-30. View abstract
  29. Jaramillo D, Connolly SA, Vajapeyam S, Robertson RL, Dunning PS, Mulkern RV, Hayward A, Maier SE, Shapiro F. Normal and ischemic epiphysis of the femur: diffusion MR imaging study in piglets. Radiology. 2003 Jun; 227(3):825-32. View abstract
  30. Rivkin MJ, Vajapeyam S, Hutton C, Weiler ML, Hall EK, Wolraich DA, Yoo SS, Mulkern RV, Forbes PW, Wolff PH, Waber DP. A functional magnetic resonance imaging study of paced finger tapping in children. Pediatr Neurol. 2003 Feb; 28(2):89-95. View abstract
  31. Mulkern RV, Vajapeyam S, Robertson RL, Caruso PA, Rivkin MJ, Maier SE. Biexponential apparent diffusion coefficient parametrization in adult vs newborn brain. Magn Reson Imaging. 2001 Jun; 19(5):659-68. View abstract
  32. Tzika AA, Robertson RL, Barnes PD, Vajapeyam S, Burrows PE, Treves ST, Scott RM. Childhood moyamoya disease: hemodynamic MRI. Pediatr Radiol. 1997 Sep; 27(9):727-35. View abstract
  33. Tzika AA, Vajapeyam S, Barnes PD. Multivoxel proton MR spectroscopy and hemodynamic MR imaging of childhood brain tumors: preliminary observations. AJNR Am J Neuroradiol. 1997 Feb; 18(2):203-18. View abstract