MRC/UCT Medical Imaging Research Unit

Screening for fetal alcohol syndrome using stereo-photogrammetry

Tania Douglas, Ernesta Meintjes

Collaborators: Denis Viljoen – Foundation for Alcohol-Related Research

Postdoctoral fellow: Mahesh Veezhinathan

Completed student projects:

o Rex Grobbelaar (MSc, 2005) Stereo facial image matching to aid in fetal alcohol syndrome screening

o Tinashe Mutsvangwa (MSc, 2006) Statistical analysis of facial landmark data for optimization of fetal alcohol syndrome diagnosis

Current student projects:

o Tinashe Mutsvangwa, Stereophotogrammetric facial analysis for diagnosis of fetal alcohol syndrome in infants

o Mahalingam Veeraragoo, Pattern recognition to detect fetal alcohol syndrome in stereo facial images

Description:

Fetal alcohol syndrome (FAS), which occurs as a consequence of excessive maternal alcohol ingestion during pregnancy, is one of the most common preventable causes of mental retardation worldwide. The highest prevalence of FAS worldwide has been found among first-grade children in a wine-growing region in the Western Cape province of South Africa. Conventional diagnosis of FAS relies heavily on the measurement of facial distances to identify a characteristic facial phenotype and requires intensive specialist participation, making it a costly procedure. This study aims to provide, using a stereo-photogrammetric approach, a cost-effective and easily deployed tool for the rapid evaluation of populations at risk for FA. Image processing methods and statistical shape analysis (geometric morphometrics) are being explored as means to identify the facial dysmorphology associated with FAS.

Landmark-based facial shape variation between children with fetal alcohol syndrome and control subjects; application of generalised Procrustes analysis and principal component analysis. The solid line indicates the mean facial shape across all subjects. The dotted lines indicate the normal shape and the FAS shape in the left and right columns, respectively. Features of interest: o Underdeveloped midface o Microcephaly o Longer and slightly smoother philtrum o Shorter outer canthal distances o Small palpebral fissure lengths

Recent publications:

Journal papers:

– E.M. Meintjes, T.S. Douglas, F. Martinez, C.L. Vaughan, L.P. Adams, A. Stekhoven, D. Viljoen. A stereo-photogrammetric method to measure the facial dysmorphology of children in the diagnosis of Fetal Alcohol Syndrome. Medical Engineering & Physics, 24(10):683-689, 2002.

– T.S. Douglas, F. Martinez, E.M. Meintjes, C.L. Vaughan, D. Viljoen. Eye feature extraction for diagnosing the facial phenotype associated with Fetal Alcohol Syndrome. Medical & Biological Engineering & Computing, 41(1):101-106, 2003.

– T.S. Douglas, E.M. Meintjes, C.L. Vaughan, D. Viljoen. The role of depth in eye distance measurements: comparison of single and stereo-photogrammetry, American Journal of Human Biology, 14(4):573-578, 2003.

– T.S. Douglas. Image processing for craniofacial landmark identification and measurement: a review of photogrammetry and cephalometry. Computerized Medical Imaging and Graphics, 28(7):401-409, 2004.

– T.S. Douglas, D.L. Viljoen. Eye measurements in 7 year-old black South African children. Annals of Human Biology, 33(2):241:254, 2006.

– R. Grobbelaar, T.S. Douglas. Stereo image matching for facial feature measurement to aid in Fetal Alcohol Syndrome screening. Medical Engineering & Physics, 29(4):459-464, 2007.

– T.E.M. Mustvangwa, T.S. Douglas. Morphometric analysis of facial landmark data to characterize the facial phenotype associated with Fetal Alcohol Syndrome. Journal of Anatomy, 210:209-220, 2007.

Book chapter:

– E.M. Meintjes, T.S. Douglas. Diagnosis of Fetal Alcohol Syndrome: measurement of the facial dysmorphology. In Comprehensive Handbook of Alcohol Related Pathology, Eds: V.R. Preedy and R.R. Watson, Academic Press, ISBN 0125643705, 2004.

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