Is the presence of linear fracture a predictor of delayed posterior fossa epidural hematoma?

BACKGROUND: Though traumatic posterior fossa epidural hematoma (PFEDH) is rare, the associated rates of morbidity and mortality are higher than those of supratentorial epidural hematoma (SEDH). Signs and symptoms may be silent and slow, but rapid deterioration may set in, resulting in death. With the more frequent use of computed tomography (CT), early diagnosis can be achieved in patients with cranial fractures who have suffered traumatic injury to the posterior fossa. However, some hematomas appear insignificant or are absent on initial tomography scans, and can only be detected by serial CT scans. These are called delayed epidural hematomas (EDHs). The association of EDHs in the supratentorial-infratentorial compartments with linear fracture and delayed EDH (DEDH) was presently investigated.

METHODS: A total of 212 patients with SEDH and 22 with PFEDH diagnosed and treated in Göztepe Training and Research Hospital Neurosurgery Clinic between 1995 and 2005 were included. Of the PFEDH patients, 21 underwent surgery, and 1 was followed with conservative treatment. In this group, 4 patients underwent surgery for delayed posterior fossa epidural hematoma (DPFEDH).

RESULTS: Mean age of patients with PFEDH was 12 years, and that of the patients with SEDH was 18 years. Classification made according to localization on cranial CT, in order of increasing frequency, revealed of EDHs that were parietal (27%), temporal (16%), and located in the posterior fossa regions (approximately 8%). Fracture line was detected on direct radiographs in 48% of SEDHs and 68% of PFEDHs. Incidence of DPFEDH in the infratentorial compartment was statistically significantly higher than incidence in the supratentorial compartment (p=0.007). Review of the entire EDH series revealed that the likelihood of DEDH development in the infratentorial compartment was 10.27 times higher in patients with linear fractures than in patients with supratentorial fractures (p<0.05).

CONCLUSION: DPFEDH, combined with clinical deterioration, can be fatal. Accurate diagnosis and selection of surgery modality can be lifesaving. The high risk of EDH development in patients with a fracture line in the posterior fossa on direct radiographs should be kept in mind. These patients should be kept under close observation, and serial CT scans should be conducted when necessary.