Cavum septum pellucidum in pediatric traumatic brain injury

The cavum septum pellucidum (CSP) is a fluid-filled cavity in the thin midline structure of the septum pellucidum. The CSP has been linked to several neurodevelopmental disorders, but it also occurs as a result of head injury. The aims were to assess the presence and characterization of the CSP in youth with traumatic brain injury (TBI), to assess whether injury severity or IQ measures were related to CSP size, and to examine brain morphometry changes associated with the CSP size. Ninety-eight survivors of TBI and 34 control children underwent magnetic resonance imaging (MRI). Numerous methods were used to define the presence and characterization of the CSP including length, classification of abnormally large CSP, rating of the CSP, and volume. There was no difference in presence of CSP between TBI patients and controls; however, there was larger and more severely graded CSP in the patient group. Size of the CSP correlated positively with injury severity, and regions that correlated most significantly with CSP size were the right entorhinal cortex and bilateral hippocampus. Characterizing the CSP and related brain changes may provide important information concerning disturbances seen after a TBI.