New Severity Indices for Quantifying Single-Suture Metopic Craniosynostosis

Abstract

OBJECTIVE To describe novel severity indices with which to quantify severity of trigonocephaly malformation in children diagnosed with isolated metopic synostosis. METHODS Computed tomographic scans of the cranium were obtained from 38 infants diagnosed with isolated metopic synostosis and 53 age-matched control patients. Volumetric reformations of the cranium were used to trace two-dimensional planes defined by the cranium-base plane and well-defined brain landmarks. For each patient, novel trigonocephaly severity indices (TSI) were computed from outline cranium shapes on each of these planes. The metopic severity index based on measurements of interlandmark distances was also computed and a receiver operating characteristic analysis used to compare the accuracy of classification based on TSIs versus that based on the metopic severity index. RESULTS The proposed TSIs are a sensitive measure of trigonocephaly malformation that can provide a classification accuracy of 96% with a specificity of 95%, in contrast with 82% of the metopic severity index at the same specificity level. CONCLUSIONS We completed exploratory analysis of outline-based severity measurements computed from computed tomographic image planes of the cranium. These TSIs enable quantitative analysis of cranium features in isolated metopic synostosis that may not be accurately detected by analytic tools derived from a sparse set of traditional interlandmark and semilandmark distances.

Little Evidence of Association Between Severity of Trigonocephaly and Cognitive Development in Infants With Single-Suture Metopic Synostosis

“…18 The TSI is outline based and can be measured on any of the 3 cranial image planes that we investigated. Our previous work suggested that the TSI in the M plane yielded the best accuracy in distinguishing metopic synostosis from nonsynostotic cranial shapes; thus, we incorporated only TSI in the M plane measurements in the current work.…”

“…To quantify severity of trigonocephaly, we applied the recently described trigonocephaly severity index (TSI), which incorporates data regarding the outline of a cranial shape extracted from 3-dimensional (3D) computed tomography (CT) images. 18 We showed in a previous study that the TSI distinguished metopic synostosis patients from nonsynostotic control infants with 96% accuracy. 18 …”

“…18 We showed in a previous study that the TSI distinguished metopic synostosis patients from nonsynostotic control infants with 96% accuracy. 18 …”

Objective Assessment of the Interfrontal Angle for Severity Grading and Operative Decision-Making in Metopic Synostosis

“…[3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Because metopic synostosis, like all craniosynostosis, is a skeletal problem, craniofacial surgeons have scrutinized radiographs for different features that might be useful for diagnosis and classification. Whitaker et al insightfully argued for differentiation of synostosis from normal fusion based on the "omega sign," a distinctive feature of the pathologic suture in cross-section.…”

Automatical Cranial Suture Detection based on Thresholding Method

“…Some researches tried to determine the diagnosis by quantifying the malformation of the cranium for making automatic Craniosynostosis diagnose system. Another author proposes a method for evaluating the degree of using the anthropometric indices on cranial CT images [4][5][6][7][8][9]. However, merely using cranial shape data, the result was not satisfactory accurate.…”