Postnatal diagnosis of single-suture craniosynostosis with cranial ultrasound: a systematic review

Fontanellar bone - A rarity in pediatric cranial abnormalities

Background

Fontanelles, membranous gaps in the infant skull, are integral for accommodating the expansion of the skull by the growing brain postnatally. The anterior fontanelle, situated at the frontal-parietal bone intersection, typically closes gradually within the first two years. Fontanellar bone, an exceedingly rare ossification anomaly of the anterior fontanelle, clinically mimics craniosynostosis.

Case Description

We present the case of a 22-day-old male with an almost closed anterior fontanelle who underwent evaluation. Prenatal and postnatal history were unremarkable. Physical examination revealed a well-nourished infant with a nearly closed fontanelle but no other anomalies. The initial diagnosis was craniosynostosis; however, a head computed tomography scan revealed fontanellar bone. Consequently, a conservative management approach with regular follow-ups was adopted.

Conclusion

This case provides valuable insights into fontanellar bone, emphasizing its consideration in differential diagnoses for almost closed anterior fontanelles. The report aims to enhance awareness and understanding of this rare condition, promoting accurate diagnosis and optimal patient outcomes.

Making the Diagnosis in Sagittal Craniosynostosis-It's Height, Not Length, That Matters

INTRODUCTION

This study assesses the diagnostic reliability of a novel photogrammetric measurement to distinguish sagittal craniosynostosis (SS) from control and false positive cases (SNS).

METHODS

Head CTs from 2014-2020 were reviewed for patients with sagittal synostosis (SS, n = 177), presumed sagittal synostosis with normal imaging (SNS, n = 30), and controls (n = 100). Using preoperative clinical photographs and CTs, a measurement reflecting the anterior-posterior location of the vertex was measured using an angle drawn between the cranial vertex, nasion, and opisthocranion (VNO) in profile view, with the head in a neutral position.

RESULTS

Mean age at pre-operative head CT was 9.5 months for the SS cohort, 4.2 months for the SNS cohort, and 8.9 months for controls (p = .327). Mean age at pre-operative clinical photograph was 9.5 months for the SS cohort and 4.2 months for the SNS cohort (p = .149). Pearson correlations revealed no significant association between age and VNO angle. The average VNO angle measured on clinical photographs was 54.7° ± 3.8° for the SS group, 43.1° ± 2.2° for the SNS group, and 41.1° ± 3.7° for controls (p < .001). Receiver operating characteristic (ROC) analysis yielded a cut-off of ≥ 50° to identify SS. Diagnostic sensitivity and specificity were 96.6% and 99.2%, respectively. Three-rater analysis yielded an average ICC of 0.742 (p = .004).

CONCLUSIONS

Measurement of the VNO angle is a reliable screening tool to diagnose sagittal craniosynostosis, with an angle of 50° or more suggesting suture synostosis. This method relies on the relationship between the anterior displacement of the vertex and occipital bulleting to approach the diagnostic accuracy of CT imaging.