A CT-study of the Cranial Suture Morphology and its Reorganization during the Obliteration

Obliteration of the cranial sutures is an age-dependent process. Its premature occurrence (craniosynostosis) causes different craniofacial deformations, dependent on the affected suture(s). The understanding of the suture morphology and the remodeling processes during the obliteration is essential for early diagnosis and treatment of the premature closure. This study aimed to investigate the morphology of open and obliterated sutures and to perform comparison analysis on the 3D images obtained by both industrial and medical computed tomography (CT) systems with various resolutions. A segment of the sagittal suture of dry skulls of known age and sex was scanned using Nikon XTH 225, a n industrial CT system , developed by Nikon Metrology. The same section of the sagittal suture was observed on patients undergoing CT scanning with a multislice system Toshiba Aquilion 64 with 0.5 mm slice thickness. For 3D visualization , VGStudioMax 2.2 were used. The suture morphology was observed in coronal section on sequential 2D slices. M icro-CT (µCT) scanning of dry skulls enabled calculation of the morphometric parameters and visualization of the microarchitecture of the suture and its reorganization during the obliteration, unlike the CT imaging of patients, where the sutures were scarcely discernable. In the entirely open sections of the suture the bone edges were separated by a gap of various widths. As the obliteration proceeded, the gap gradually reduced and the bone edges got into a contact. In the final stages, the traces from the contact faded away and the sutural area became a homogenous structure of increased integrity. The µCT scanning of dry bones is a powerful non-destructive technique for examination of the suture morphology. Remodeling of the suture during the obliteration leads to gradually diminishing of the gap between the bone edges to their entire coalescence.