3-Dimensional Morphometric Outcomes After Endoscopic Strip Craniectomy for Unicoronal Synostosis

Endoscopic strip craniectomy with postoperative helmeting (ESCH) for unicoronal synostosis has shown to be a less morbid procedure when compared with fronto-orbital remodeling (FOR). We aim in this pilot study to report objective methods and quantitative morphologic outcomes of endoscopically treated unicoronal synostosis using 3-dimensional surface scans.

Our electronic records were reviewed for ophthalmological, neurodevelopmental outcomes, and helmet-related complications. For morphologic outcomes, the following parameters were used: Cranial Index, Cranial Vault Asymmetry Index, Anterior Symmetry Ratio (ASR), and Root Mean Square between the normal and synostotic sides of the head. Three-dimensional stereophotogrammetry scans were evaluated at 3 time points preoperative, 6 months post-op, and at the end of the treatment, which was compared with age-matched scans of normal controls and FOR patients. Nonparametric tests were used for statistical analysis.

None of the ESCH cases developed strabismus, major neurodevelopmental delay, or helmet complications. All morphologic parameters improved significantly at 6 months post-op except for the Cranial Vault Asymmetry Index. The ASR was the only parameter to change significantly between 6 months post-op and final scans. At end of helmet treatment, ASR and Root Mean Square differed significantly between the ESCH and both FOR and control groups.

Endoscopic strip craniectomy with postoperative helmeting for single unicoronal synostosis had excellent clinical outcomes. Most of the improvement in head morphology occurred in the first 6 months of treatment. Despite the normalization of the overall head shape, there was residual asymmetry in the frontal and temporal regions of the head.