POSITIONING PLAGIOCEPHALY AND TRUE CRANIOSYNOSTOSIS – RELIABLE DIAGNOSIS BY HIGH-FREQUENCY SONOGRAPHY

Purpose: The incidence of positioning plagiocephaly has been an increasing diagnostic and therapeutic problem since international pediatric societies had been advocating to lay infants on their back preventing sudden infant death syndrome. Even mortality has been decreased dramatically, roentgenography and CT-imaging with high radiation doses are frequently performed to exclude true synostosis.

Methods and Materials: In 2004 83 children, 3–14 month old, with a head deformity have been admitted to our craniofacial outpatient clinic. Patient history and clinical examination were followed by high-frequency ultrasound (10MHz) of the calvarian sutures to check the accuracy of this method differentiating positioning plagiocephaly from true synostosis. Sonographic findings were correlated to morphological histology.

Results: Normal sutures are characterized by a less echogenic gap of 0.4–2.6mm with an echogenic thin bridging (<0.3mm) of the pericranium and dura mater. This could be reliable identified in 51 children with an unilateral flattening of the occipital head excluding lambdoid synostosis. In five children sonographic investigation remained unsatisfactory (artefacts to movement and hair). Roentgenography confirmed in one of five patients unilateral synostosis of lambdoid suture. Bilateral synostosis was found in none of our patients. 27 children were found sonographically to have short- or longdistant, highly echogenic, bony-like bridging suspecting true synostosis. Diagnosis was confirmed by roentgenography.

Conclusions: Patient history and clinical examination may be already leading in diagnosing the underlying course of a head deformity. High-frequency sonography should noted as an important step in the diagnostic work-up enabling to confirm correct diagnosis of positioning plagiocephaly and synostosis with a high sensitivity, thereby radiation doses may be deminished to a minimum.