Several hydrocephalus predictors were identified; these included distance from the midline, hygroma, age, injury severity, subarachnoid or intraventricular hemorrhage, delayed time to craniotomy, repeated operation, and duraplasty. However, results differed among studies. The impact of DC on hydrocephalus remains controversial 1).
It is demonstrated that the occurrence of posttraumatic hydrocephalus (PTH) is high in patients with large decompressive craniectomy (DC). Patients with low GCS and bilateral decompression tend to develop PTH after DC. Duraplasty in DC might facilitate reducing the occurrence of PTH. Patients with PTH concomitant skull defects should be managed deliberately to restore the anatomical and physiological integrity so as to facilitate the neurological resuscitation 2).
A study suggests that PTH development is multifactorial and shows that PTH is not that rare. Fotakopoulos et al showed a correlation between craniectomy size and the incidence of PTH 3).
They analyzed the area of craniotomy and the distance of the craniotomy from the midline. Results showed that patients who had undergone craniectomies with a superior limit less than 25 mm from the midline had a markedly increased risk of developing hydrocephalus. They hypothesized, based on the Starling resistor concept, that during each cardiac cycle in which extracellular fluid is produced during systole and absorbed in diastole, an imbalance between the production and absorption of extracellular fluid in favor of absorption would cause a decrease in brain parenchyma volume and consequently increase the size of the ventricles 4).
The presence of interhemispheric hygroma IHHs was a predictive radiological sign of hydrocephalus development within the first 6 months of DC in patients with severe head injury 5).