Mercedes Benz pattern craniosynostosis associated with Chiari malformation type 1: A case report of a rare condition

Abstract

Introduction: Craniosynostosis results from the premature fusion of cranial sutures and is classified as complex when it affects multiple sutures. The abnormal and rare fusion of the sagittal and bilateral lambdoid sutures is known as the Mercedes-Benz (CMB)  pattern responsible for up to 0.7% of craniosynostoses. It's characterized by flattening of the occipital bone and sub-lambdoid depression. Additionally, the Arnold-Chiari malformation, one of the anomalies associated, occurs due to the junction of deformities in the posterior fossa and rhombencephalon. Type 1 (CM1) is the most incident and less severe, represented by the pointed shape of the cerebellar tonsils.

Objective: The objective of this article is to report a rare case presentation of Mercedes Benz pattern Craniosynostosis associated with Arnold Chiari malformation 

Case presentation: Male patient, 11 months old, diagnosed with CMB associated with CM1, presenting with anterior turribrachycephaly and occipital brachycephaly. The diagnosis was made after the 10th month of life, with typical findings on computed tomography and cerebellar tonsil herniation (CTH) on magnetic resonance imaging (MRI). No signs of neurodevelopmental delay were observed, and there is no history of cranial malformations in the family. At 11 months, the patient underwent neurosurgery involving cranial parietal remodeling to correct craniosynostosis, along with posterior fossa decompression to address CM1.

Conclusion: Neurosurgical techniques like parietal remodeling and posterior decompression, despite their complexity, play a central role in addressing CMB. It's crucial to discuss this rare condition to ensure early diagnosis and treatment, facilitating an efficient approach and preventing potential later consequences.