The CORE Group


Spring Membership Meeting
2002

April 22 - 26, 2002
Project HOPE
Millwood, Virginia

Where am I?     Home / Resources / Meeting Reports / Spring Membership Meeting 2002 / Non-Invasive Assessment of Micronutrient Status

Non-Invasive Assessment of Micronutrient Status

A round-table session with practical demonstrations using a prototype. Moderator: Luis Benavente (co-chair CORE Nutrition Working Group). Presenters: Ciro Franco (MOST): magnitude and distribution of MN deficiencies, assessment methods; Babs Soller (University of Massachusetts): NIRS technology and its application to assess anemia.

Session objectives:

  1. Describe briefly the magnitude and distribution of anemia and vitamin A deficiency
  2. Identify the advantages and disadvantages of current procedures to assess MN status.
  3. Describe the basic optical principles of reflectance spectroscopy and the ideal characteristics of a device to assess MN status in the field without drawing blood.
  4. Identify possible collaborative venues between CORE, academic institutions and the medical device industry to develop such device

NIRS (Near Infrared Spectroscopy) uses reflected or transmitted light through the skin of subjects, allowing the measurement of substances for screening, diagnosis and monitoring. The number of optical sensor systems used in clinical applications has multiplied during the last years, but the equipment developed for clinical use costs thousands of dollars. The progress necessary to apply this technology for public health use involves interdisciplinary researchers and product makers.

Get adobe PDF Reader

Note: If you have Power Point installed on your computer, click the Download tab to view the presentation using your software. If you do not have Power Point you may View the slides using Adobe (pdf).

NIRS technology: Babs Soller (University of Massachusetts) View Download
Anemia: Ciro Franco (MOST) View Download

Resources:

  • OMNI: Anemia detection methods, 1997.
  • Bodenner D: Noninvasive measurement of plasma metabolites using near-infrared spectroscopy. IN: Emerging technologies for Nutrition research, 1997 pp 345-358, Natl Academy Press, Washington DC.
  • Abstract: Investigation of Noninvasive in Vivo Blood Hematocrit Measurement Using NIR Reflectance Spectroscopy and Partial Least-Squares Regression. Applied Spectroscopy February 2000 Volume 54 (2) by Songbiao Zhang, Babs R. Soller, Shubjeet Kaur, Kristen Perras, and Thomas J. Vander Salm, Department of Surgery, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655-0304 USA. Hematocrit (Hct), the volume percent of red cells in blood, is monitored routinely for blood donors, surgical patients, and trauma victims, and requires blood to be removed from the patient. An accurate, noninvasive method for directly measuring hematocrit on patients is desired for these applications. The feasibility of noninvasive hematocrit measurement using NIR spectroscopy and partial least-squares (PLS) techniques was investigated and methods of in-vivo calibration examined. Twenty Caucasian patients undergoing cardiac surgery on cardiopulmonary bypass were randomly selected to form two study groups. A fiber-optic probe was attached to the patient's forearm and NIR spectra were continuously collected during surgery.
Blood samples were simultaneously collected and reference Hct measurements were made by using the spun capillary method. PLS multivariate calibration techniques were applied to investigate the relationship between spectral and Hct changes. Single patient calibration models were developed with good cross-validated estimation of accuracy (~ 1 Hct %) and trending capability for most patients. Time-dependent system drift, patient temperature, and venous oxygen saturation were not correlated with the hematocrit measurements. Multi-subject models were developed for prediction of independent subjects. These models demonstrated a significant patient-specific offset that was shown to be partially related to spectrometer drift. The remaining offset is attributed to the large spectral variability of patient tissue and a significantly larger set of patients would be required to adequately model this variability. After removing the offset the cross-validated estimation of accuracy is 2 Hct %.

Babs Soller is a Research Associate Professor of Surgery at the University of Massachusetts Medical School. She is also affiliated with the University's Department for Biomedical Engineering and Medical Physics. Babs received her MA and PhD in Physical Chemistry from Princeton University.

Ciro Franco is a physician with a Masters in Public Health from Johns Hopkins University and a Diploma in Tropical Disease from the Prince Leopold Institute of Tropical Medicine in Belgium. He has over 20 years' experience in medicine and public health, with 16 years focused on international health issues and 10 years of long-term assignments in Africa. His areas of expertise encompass a wide range of health care programs, including reproductive health (family planning, maternal health, HIV/AIDS/STI), child health (IMCI, malaria, ARI, diarrhea), and nutrition (Vitamin A, anemia). He is now working with the MOST Project as the Field Operations Program Director. (Continued next page)

Dr. Luis Benavente, as the Associate Director for Maternal and Child Health programs, works closely with the Director to backstop Project HOPE's child survival programs in Guatemala, Peru, and Nicaragua. He previously served HOPE as Program Director of a Child Survival Program in the Amazon Basin of Perú.

Dr. Benavente was Professor and Head of the Department of Public Health at Universidad Peruana Cayetano Heredia, and he was the Director of the National Food and Nutrition Institute in Peru. Dr. Benavente holds a Medical Degree and a Master of Science Degree in Microbiology and Immunology from Universidad Peruana Cayetano Heredia.

Accredited as a Specialist in Epidemiology, he has extensively published in epidemiology of nutritional disorders, nutrition and infection, and micronutrient deficiencies. Dr. Benavente is chairing The CORE Group's Nutrition Working Group since 2001.

Back