Chronische Erweiterung des Ventrikelsytems in Patienten mit posttraumatischem Hydrozephalus nach schwerem SHT. Nur chronisch oder Unterdrainage?

Posttraumatic hydrocephalus is a well-known complication after severe head injury and typically occurs after few weeks of trauma. Usually, a CSF resorption anomaly underlies this situation. Patients mostly undergo ventriculoperitoneal shunting (VPS) with programmable valves. Nevertheless, persistent enlargement of ventricular system can be frequently observed in mid-term follow-up in TBI patients after hemicraniectomy, even though in absence of shunt underdrainage or malfunction of the valve.

We performed a retrospective analysis of all severe TBI patients (initial GCS <7) who had undergone a VP shunt implantation because of posttraumatic hydrocephalus between 2013 und 2023. Analyzed parameters included age, hemicraniectomy, traumatic findings on CT scans as t-SAB, SDH, and contusions . Ventricle width was measured on CT scan using the biventrucular width and diameter of the third ventricle at presentation as well as during follow-up at 3 and 6 months postoperatively.

25 patients with severe TBI with fully available follow-up data were included in this analysis. The median age was 48 years. 88% of the patients were male. 68% of the patients (n=17) had undergone decompressive hemicraniectomy. Initially, SDH was observed in 64% of the cases, t-SAB in 84%. Reprogramming of the shunt valve pressure was necessary in 50% of all patients. Measurements of enlargement of ventricular system were performed by assessment of biventricular diameter as well as 3rd. ventricle diameter on CT scans. Overall, 12 patients (48%) showed significant chronic enlargement in the diameter of the third- or biventricular diameter (more than 3 mm for third ventricle- and more than 10 mm of biventricular- diameter). Enlargement of ventricular system was observed in 76% of all TBI patients who needed decompressive hemicraniectomy whereas in the group of patients without hemicraniectomy only 37% developed enlargement of CSF system during follow- up.all 4 patients diagnosed of diffuse axonal injury in MRI showed enlargement of ventricular system

Our findings suggest that severe TBI patients undergoing hemicraniectomy are prone to developchronic enlargement of ventricular system regardless of multiple valve pressure reprogramming. Whether this phenomenon is associated with underlying neuroinflammatory processes emerging after severe TBI or instead, with negative pressure associated disruption of brain microstructure and stiffness remains to be elucidated with large series of TBI patients.