Micrognathia occurs isolated and as part of entities like Robin sequence (RS). An objective measurement of mandible size and growth is needed to determine the degree of micrognathia and enable a comparison of treatment outcomes. A pilot study was conducted to investigate the usability of 3-dimensional (3D) facial photogrammetry, a fast, noninvasive method, to estimate mandible size and growth in a small cohort of newborns and infants.
Exterior mandibular volume was estimated using a tetrahedron defined by 4 facial landmarks. Twelve patients with RS with different etiologies were selected and photogrammetric images were obtained prospectively in 3 patients with RS in whom mandibular growth in the first year of life was determined. We used 3 tetrahedra defined by 6 landmarks on mandibular computed tomography (CT) scans to estimate an interior mandibular volume, which we compared to the exterior mandibular volume in 10 patients.
The exterior mandibular volume using 3D photography could be determined in all patients. Signature heat maps allowed visualization of facial dysmorphism in 3D; signature graphs demonstrated similarities of facial dysmorphism in patients with the same etiology and differences from those with other diagnoses and from controls. The correlation between interior (3D photogrammetry) and exterior mandibular volumes (CT imaging) was 0.8789.
The 3D facial photogrammetry delineates the general facial characteristics in patients with different syndromes involving micrognathia, and can objectively estimate mandibular volume and growth, with excellent correlation with bony measurement. It has been concluded that 3D facial photogrammetry could be a clinically effective instrument for delineating and quantifying micrognathia.
*Department of Plastic and Reconstructive Surgery
†Department of Pediatrics, Amsterdam UMC–location AMC, University of Amsterdam, Amsterdam, the Netherlands
‡Big Data Institute and Nuffield Department of Obstetrics and Gynecology, University of Oxford, Oxford
§UCL Great Ormond Street Hospital Institute of Child Health, University College London, London, UK.
Address correspondence and reprint requests to Raoul C. Hennekam, MD, PhD, Department of Pediatrics, Room H7-236, Amsterdam UMC–location AMC, Meibergdreef 9, 1105AZ Amsterdam, the Netherlands; E-mail: firstname.lastname@example.org
Received 18 December, 2017
Accepted 19 August, 2018
RCH and PH contributed equally to this study.
PH and MS were supported in part by funds from NIAAA (U01AA014809-10) and AI by the Royal College of Surgeons Blond Research Training Fellowship.
The Medical Ethics Committee of the Amsterdam UMC–location AMC in Amsterdam had approved the study (W13_076# 13.17.0096).
The authors report no conflicts of interest.