Intracranial Volume Not Correlated With Severity in Trigonocephaly

Radiographic severity is associated with worse executive function in metopic craniosynostosis

BACKGROUND

Children with metopic synostosis have been found to have more neurocognitive and behavioral difficulties. The variables that may affect future neurodevelopmental outcomes, including presenting morphologic severity, have not been fully studied. In the largest study to date, we aimed to assess what portends worse neurocognitive and behavioral outcomes at school age.

METHODS

Children 6-18 years old with surgically corrected metopic nonsyndromic craniosynostosis underwent neurocognitive testing. Parents completed behavior rating surveys about their child: Conners-3 (ADHD), Social Responsiveness Scale-2 (autism spectrum disorder), Behavior Rating Inventory of Executive Function-2 (BRIEF-2: executive function), and Child's Behavior Checklist (overall behavior). The endocranial bifrontal angle (EBA), adjusted EBA (aEBA), frontal angle (FA), and AI-derived metopic severity score (MSS) were determined on pre-operative CT images. Multivariate linear regressions were used to evaluate the association of age at surgery and severity.

RESULTS

There were 87 children who underwent neurocognitive testing (average age 10.9 ± 3.3 years) of whom 67 also completed behavioral assessments. Greater phenotypical severity of metopic synostosis (lower FA, aEBA, and EBA) was associated with worse scores on the subscales of the BRIEF-2 (executive function) and executive subscale of the Conners-3. Increasing age at surgery was associated with worse executive function subscale scores of the Conners-3 when controlling for each severity measurement and sociodemographic risk.

CONCLUSION

Children with greater phenotypic severity of metopic synostosis have worse executive function at school age. The majority of children with metopic synostosis have signs of ADHD. Later surgeries (greater than 12 months) may impact executive functioning, regardless of the degree of severity. Future research should aim at identifying the direct structural changes to the brain.

New diagnostic criteria for metopic ridges and trigonocephaly: a 3D geometric approach

BACKGROUND

Trigonocephaly occurs due to the premature fusion of the metopic suture, leading to a triangular forehead and hypotelorism. This condition often requires surgical correction for morphological and functional indications. Metopic ridges also originate from premature metopic closure but are only associated with mid-frontal bulging; their surgical correction is rarely required. Differential diagnosis between these two conditions can be challenging, especially in minor trigonocephaly.

METHODS

Two hundred seven scans of patients with trigonocephaly (90), metopic rigdes (27), and controls (90) were collected. Geometric morphometrics were used to quantify skull and orbital morphology as well as the interfrontal angle and the cephalic index. An innovative method was developed to automatically compute the frontal curvature along the metopic suture. Different machine-learning algorithms were tested to assess the predictive power of morphological data in terms of classification.

RESULTS

We showed that control patients, trigonocephaly and metopic rigdes have distinctive skull and orbital shapes. The 3D frontal curvature enabled a clear discrimination between groups (sensitivity and specificity > 92%). Furthermore, we reached an accuracy of 100% in group discrimination when combining 6 univariate measures.

CONCLUSION

Two diagnostic tools were proposed and demonstrated to be successful in assisting differential diagnosis for patients with trigonocephaly or metopic ridges. Further clinical assessments are required to validate the practical clinical relevance of these tools.

Classification of Skull Shape Deformities Related to Craniosynostosis on 3D Photogrammetry

Implementation of the Utrecht Cranial Shape Quantificator (UCSQ) classification method on 3D photogrammetry in patients with different types of craniosynostosis is the aim of the present study. Five children (age <1 year) of every group of the common craniosynostoses (scaphocephaly, brachycephaly, trigonocephaly, right-sided and left-sided anterior plagiocephaly) were randomly included. The program 3-Matic (v13.0) was used to import and analyze the included 3dMD photos. Three external landmarks were placed. Using the landmarks, a base plane was created, as well as a plane 4 cm superior to the base plane. Using UCSQ, we created sinusoid curves of the patients, the resulting curves were analyzed and values were extracted for calculations. Results per patient were run through a diagnostic flowchart in order to determine correctness of the flowchart when using 3D photogrammetry. Each of the patients (n=25) of the different craniosynostosis subgroups is diagnosed correctly based on the different steps in the flowchart. This study proposes and implements a diagnostic approach of craniosynostosis based on 3D photogrammetry. By using a diagnostic flowchart based on specific characteristics for every type of craniosynostosis related to specific skull deformities, diagnosis can be established. All variables are expressed in number and are therefore objective.