Insight into the Pathophysiologic Mechanisms behind Cognitive Dysfunction in Trigonocephaly

The relationship between trigonocephaly and cognitive problems might be explained by: secondary mechanical factors related to growth restriction of the skull, and primary structural defects caused by a shared mechanism related to brain developmental disorder(s) and skull malformation. However, because the exact pathophysiology remains unknown, we examined the pathophysiologic mechanisms behind cognitive dysfunction in patients with trigonocephaly, with an aim of providing a model for cognitive dysfunction based on routinely available variables.

Included were 72 patients with trigonocephaly who were operated on. Postoperatively, intelligence was assessed prospectively. The two independent variables, secondary mechanical and primary brain developmental mechanisms, were evaluated retrospectively. Computed tomographic imaging was used to assess skull volume and severity of the frontal stenosis (secondary mechanical factors), width of the central part of the lateral ventricles, and other structural brain anomalies (primary brain developmental factors). Extracranial congenital anomalies were also taken into account.

No association was found between secondary mechanical factors and postoperative IQ score. Width of the central part of the lateral ventricles, and an interaction effect between this width and additional extracranial anomalies, showed a significant negative association with postoperative IQ.

Primary brain developmental disorders seem to play an important role in the development of cognitive problems in trigonocephaly. Assessment of width of the central part of the lateral ventricle scores and additional extracranial congenital anomalies for the early prediction of cognitive problems in patients with trigonocephaly could be clinically valuable and can be performed using routinely available tools.