"photoanthropometric investigation of facial structures in iranian children with down syndrome and normal controls"

the photoanthropometric method was used to study the facial features in 136 iranian children with down syndrome, aged 4 to 14 years. nineteen parameters were investigated and compared to an age related control group of 100 normal iranian children. the obtained measurements were related to reference values in the same faces. the normal range was defined by age related index values between the 20th and 80th percentile in the collective of normal iranian children. five parameters were considered as characteristic facial traits of iranian children with down syndrome by index values outside these percentiles in ≥ 50% of the studied collective: low midface; narrow and upslanted palpebral fissures ; short, and anteriorly rotated ears. twelve parameters were considered as additional facial traits by index values outside these percentiles in ≥ 30% < 50% of the studied collective: broad inner canthal distance; prominent nose root; short nose back; everted nasal base; long nasolabial distance; forwards inclined integumental upper lip; narrow mouth fissure; high and prominent chin; high-set, narrow ears and narrow conchae. these results contribute to an objective definition of facial traits in children with down syndrome in a homogeneous ethnic population.