Neuroradiology Case of the Week

Case 37

Francisco Garcia-Morales, MD and P-L Westesson, MD, PhD, DDS

Clinical Presentation: Five-month-old infant presents with an abnormal head shape.

Radiological Findings: CT scan with 3-dimensional reconstruction shows closure of the right coronal suture with associated head deformity (Figs. 1 & 2). The MIP image (Figs. 3B) demonstrates the closure of the right coronal suture. A rotation of the MIP images (Fig. 4) further demonstrates the closure of the right coronal suture with the resulting skull deformity.

Figure 1: 3D CT reconstruction in AP projection shows the asymmetric closure (arrow) of the right side of the coronal suture, with asymmetry of the skull.	Figure 2: 3D CT reconstruction right lateral projection better depicts the closure premature closure (arrows) of the right side of the coronal suture.
Figure 3: Comparative Vertex view of 3D CT reconstruction (A) and CT-MIP (B) showing the abnormally premature right coronal suture (arrow).
Figure 4: Rotational MIP demonstrating the abnormal and normal sutures.

Diagnosis: Craniosynostosis with premature closure of the right coronal suture.

Discussion:
   Craniosynostosis results from premature fusion of the sutures. It is thought that the premature closure of the suture results in growth retardation of the skull, which secondarily may lead to functional abnormalities of mentation, breathing, feeding and vision. The majority of cranial synostosis involves a single suture and is non-syndromic [2].
   Craniosynostosis represents a diversity of condition which often requires early recognition in order to predict associated complication and insure preventive rather than symptomatic intervention. Cranial synostosis has been classified as single versus multiple sutures synostosis. The single suture synostosis involves the sagittal, coronal, lambdoid or metopic suture. The multiple suture synostoses are more often associated with an underlying syndrome such as the Apert syndrome, Crouzon syndrome, Pfeiffer syndrome, Saethre-Chotzen syndrome or Carpenter syndrome [2].
   Before the event of cross-sectional imaging, plain films were the standard. In today’s imaging CT is the standard for evaluating craniosynostosis. Recent studies [1] have shown that both 3-D CT and MIP (maximal intensity projection) can better depict the patency of skull sutures making it an important imaging tool to evaluate the extent of the synostosis and associated deformity and helps to plan and determine the extent of surgery.

References:

1. Medina LS. Three-dimensional CT maximum intensity projections of the calvaria: A new approach for diagnosis of cranial synostosis and fractures. AJNR Amer J Neuroradiol 2000;21:1951-1954.
2. Aviv RI, Roger E, Hall CM. Cranial synostosis. Clin Radiol 2002;57:93-102.