Pure Bilateral Lambdoid and Posterior Sagittal Synostosis (Mercedes-Benz Syndrome): Case Report and Literature Review.

BACKGROUND

Bilateral lambdoid and posterior sagittal synostosis is a rarely encountered multisutural craniosynostosis accounting for 0.3%-0.7% of all craniosynostoses. It has been named "Mercedes-Benz Syndrome" (MBS) because of the bone ridges that resemble the Mercedes-Benz logo. The typical head shape is usually described as anterior turricephaly combined with mild brachycephaly. We describe a case of pure MBS without involvement of other sutures. Since we believe that MBS is a different pathology when other sutures are involved, we will discuss our case with a review of the literature, including all reported cases of bilateral lambdoid and posterior sagittal synostosis with no other sutures involved but sagittal and bilateral lambdoid.

CASE DESCRIPTION: A 3-month-old female baby came to our attention because of a turrycephalic appearance of the head. Findings of the neurologic examination were unremarkable. Computed tomography scan showed premature fusion of posterior third of sagittal suture and bilateral lambdoid suture. Magnetic resonance imaging did not show relevant intracranial abnormalities. She underwent sagittal decompression extended posteriorly below the lambdoid suture combined with biparietal decompression to obtain expansion of both parieto-frontal bones and posterior fossa. Post-operative course was uneventful. Follow-up at 3 months showed a good aesthetic result, and results of the neurologic examination were unremarkable.

CONCLUSIONS

Pure MBS is a rare condition that unlike other multisutural complex craniosynostosis is rarely associated with genetic syndromes, has a low rate of associated intracranial anomalies, and has less need for more skull-remodeling surgery. The choice of the most suitable surgical procedure must be tailored on the patient, considering preoperative head appearance and eventually associated anomalies.