Dunaway, D.J. (David J.)
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- A novel soft tissue prediction methodology for orthognathic surgery based on probabilistic finite element modelling(Public Library of Science, 2018) Rodriguez-Florez, N. (Naiara); Badiali, G. (Giovanni); Schievano, S. (Silvia); Ruggiero, F. (Federica); Dunaway, D.J. (David J.); Marchetti, C. (Claudio); Jeelani, O. (Owase); Bianchi, A. (Alberto); Borghi, A. (Alessandro); Knoops, P.G.M. (Paul G. M.); Breakey, R.W.F. (Richard W. F.)Repositioning of the maxilla in orthognathic surgery is carried out for functional and aesthetic purposes. Pre-surgical planning tools can predict 3D facial appearance by computing the response of the soft tissue to the changes to the underlying skeleton. The clinical use of commercial prediction software remains controversial, likely due to the deterministic nature of these computational predictions. A novel probabilistic finite element model (FEM) for the prediction of postoperative facial soft tissues is proposed in this paper. A probabilistic FEM was developed and validated on a cohort of eight patients who underwent maxillary repositioning and had pre- and postoperative cone beam computed tomography (CBCT) scans taken. Firstly, a variables correlation assessed various modelling parameters. Secondly, a design of experiments (DOE) provided a range of potential outcomes based on uniformly distributed input parameters, followed by an optimisation. Lastly, the second DOE iteration provided optimised predictions with a probability range. A range of 3D predictions was obtained using the probabilistic FEM and validated using reconstructed soft tissue surfaces from the postoperative CBCT data. The predictions in the nose and upper lip areas accurately include the true postoperative position, whereas the prediction under-estimates the position of the cheeks and lower lip. A probabilistic FEM has been developed and validated for the prediction of the facial appearance following orthognathic surgery. This method shows how inaccuracies in the modelling and uncertainties in executing surgical planning influence the soft tissue prediction and it provides a range of predictions including a minimum and maximum, which may be helpful for patients in understanding the impact of surgery on the face.
- Intracranial volume and head circumference in children with unoperated syndromic craniosynostosis.(LIPPINCOTT WILLIAMS & WILKINS, 2018-11) Rodriguez-Florez, N. (Naiara); Schievano, S. (Silvia); O'Hara, J. (Justine); James, G. (Gregory); Dunaway, D.J. (David J.); Jeelani, O. (Owase); Borghi, A. (Alessandro); Knoops, P.G.M. (Paul G. M.); Breakey, R.W.F. (Richard W. F.)Background: When analyzing intracranial volume gain resulting from operative intervention in craniosynostosis, it is necessary to understand the underlying growth. The authors sought to create comprehensive intracranial volume and occipitofrontal circumference growth charts, as measured on unoperated craniosynostotic children, and aimed to investigate whether intracranial volume and occipitofrontal circumference could act as proxy measures for each other. Methods: All preoperative Great Ormond Street Hospital patients with a diagnosis of Apert, Crouzon-Pfeiffer, or Saethre-Chotzen syndrome from the year 2004 onward were considered for this study. A control group of unaffected Great Ormond Street Hospital patients were also measured. Intracranial volume and occipitofrontal circumference were measured on the same scans. To study correlation between intracranial volume and occipitofrontal circumference, logarithmic fits were assessed. Results: One hundred forty-seven craniosynostotic children with 221 preoperative scans were included (81 Apert, 81 Crouzon, 31 Pfeiffer, and 28 Saethre-Chotzen). The control group comprised 56 patients with 58 scans. Apert intracranial volume curves were significantly larger than those of other syndromes from 206 days onward; occipitofrontal circumference curves were not significantly different. The correlation coefficient between intracranial volume and occipitofrontal circumference was R-2 = 0.87 for all syndromes combined and R-2 = 0.91 for the control group. Conclusions: Apert syndrome children have a larger intracranial volume than children with other syndromic craniosynostotic conditions and unaffected children but maintain a similar occipitofrontal circumference. This study demonstrates high correlation between intracranial volume and occipitofrontal circumference with clinical care implications. The authors' reference growth curves can be used to monitor intracranial volume change over time and correct operative change for underlying growth.
- The esthetic perception of morphological severity in scaphocephalic patients is correlated with specific head geometrical features(2023) Rodriguez-Florez, N. (Naiara); Koudstaal, M. (M.); Schievano, S. (Silvia); Ruggiero, F. (Federica); Dunaway, D.J. (David J.); Heutinck, P. (Pam); Jeelani, O. (Owase); Borghi, A. (Alessandro); Ajami, S. (Sima)Objective To investigate the relationship between perception of craniofacial deformity, geometric head features, and 3D head shape analyzed by statistical shape modeling (SSM). Patients A total of 18 unoperated patients with scaphocephaly (age = 5.2 +/- 1.1m)-6 were followed-up after spring-assisted cranioplasty (SAC) (age = 9.6 +/- 1.5m)-and 6 controls (age = 6.7 +/- 2.5m). Main Outcome Measures 3D head shapes were retrieved from 3D scans or computed tomography (CTs). Various geometrical features were measured: anterior and posterior prominence, take-off angle, average anterior and posterior lateral and horizontal curvatures, cranial index (CI) (cranial width over length), and turricephaly index (TI) (cranial height over length). SSM and principal component analysis (PCA) described shape variability. All models were 3D printed; the perception of deformity was blindly scored by 9 surgeons and 1 radiologist in terms of frontal bossing (FB), occipital bulleting (OB), biparietal narrowing (BN), low posterior vertex (LPV), and overall head shape (OHS). Results A moderate correlation was found between FB and anterior prominence (r = 0.56, P < .01) and take-off angle (r = - 0.57, P < .01). OB correlated with average posterior lateral curvature (r = 0.43, P < 0.01) similarly to BPN (r = 0.55, P < .01) and LPV (r = 0.43, P < .01). OHS showed strong correlation with CI (r = - 0.68, P < .01) and TI (r = 0.63, P< .01). SSM Mode 1 correlated with OHS (r = 0.66, p < .01) while Mode 3 correlated with FB (r = - 0.58, P < .01). Conclusions Esthetic cranial appearance in craniofacial patients is correlated to specific geometric parameters and could be estimated using automated methods such as SSM.
- Three-dimensionalenvironment and vascularization induce osteogenic maturation of human adipose-derived stem cells comparable to that of bone-derived progenitors(Wiley, 2020) Rodriguez-Florez, N. (Naiara); Ferretti, P. (Patrizia); New, S.E.P. (Sophie E. P.); Gardner, O.F.W. (Oliver F.W.); Dunaway, D.J. (David J.); Bulstrode, N.W. (Neil W.); Ibrahim, A. (Amel); Borghi, A. (Alessandro); Zucchelli, E. (Eleonora)While human adipose-derived stem cells (hADSCs) are known to possess osteogenic differentiation potential, the bone tissues formed are generally considered rudimentary and immature compared with those made by bone-derived precursor cells such as human bone marrow-derived mesenchymal stem cells (hBMSCs) and less commonly studied human calvarium osteoprogenitor cells (hOPs). Traditional differentiation protocols have tended to focus on osteoinduction of hADSCs through the addition of osteogenic differentiation media or use of stimulatory bioactive scaffolds which have not resulted in mature bone formation. Here, we tested the hypothesis that by reproducing the physical as well as biochemical bone microenvironment through the use of three-dimensional (3D) culture and vascularization we could enhance osteogenic maturation in hADSCs. In addition to biomolecular characterization, we performed structural analysis through extracellular collagen alignment and mineral density in our bone tissue engineered samples to evaluate osteogenic maturation. We further compared bone formed by hADSCs, hBMSCs, and hOPs against mature human pediatric calvarial bone, yet not extensively investigated. Although bone generated by all three cell types was still less mature than native pediatric bone, a fibrin-based 3D microenvironment together with vascularization boosted osteogenic maturation of hADSC making it similar to that of bone-derived osteoprogenitors. This demonstrates the important role of vascularization and 3D culture in driving osteogenic maturation of cells easily available but constitutively less committed to this lineage and suggests a crucial avenue for recreating the bone microenvironment for tissue engineering of mature craniofacial bone tissues from pediatric hADSCs, as well as hBMSCs and hOPs.