What is the incidence of hypertelorism in Filipino frontonasal encephalocele patients?

It is unclear whether Filipinos with sincipital encephaloceles have true orbital hypertelorism or just telecanthus. Knowing this determines whether orbital osteotomies or medial canthoplasty are more appropriate corrective procedures. To evaluate this, 56 sequential Filipino sincipital encephalocele patients (28 female and 28 male, average age 66.6 months, age range 4 days to 21.8 years) were evaluated for orbital width. Soft tissue measurements of inner and outer canthal position and CT measurements of medial and lateral orbital wall position were obtained. Normative data curves by age and sex for orbital bony and soft tissue distances in normal Filipino children were developed. Data was plotted on these curves and analyzed to determine if encephaloceles were associated with medial widening alone or true hypertelorism. Inner canthal measurements for male were approximately +2.8 standard deviation (SD) and female +2.3 SD wider than average. Medial orbital wall dimensions were wider for male +1.5 SD and female +1.4 SD. Lateral orbital measurements for both male and female clustered around the normative mean (males -0.5 SD and females -0.8 SD). Female outer canthal measurements also clustered around the normative mean (+0.6 SD wider) while male outer canthal measurements averaged approximately +1.1 SD wider than mean. As expected, measurements were wider medially when compared to normative data. However, lateral bony and soft tissue widening was minimal or approached normative averages. This suggests the problem is medial widening only and less invasive procedures such as medial canthoplasty or nasal bony contouring may be the most appropriate surgical management.