Brainstem hemorrhage in descending transtentorial herniation (Duret hemorrhage).

OBJECTIVES

To review clinical and radiological findings in patients with Duret hemorrhages and to discuss the pathophysiology and differential diagnosis of these lesions.

PATIENTS AND

METHODS

We reviewed the case records of four patients with Duret hemorrhages who had been admitted to the neurological intensive care unit with supratentorial mass lesions.

RESULTS

Descending transtentorial and subfalcine herniations were present in all cases. Three patients were admitted with acute subdural hematoma and one with intraparenchymal hemorrhage. Computed tomography revealed the presence of blood in the mesencephalon and upper pons. Three patients died; one survived with severe disabilities.

DISCUSSION: Duret hemorrhages are typically located in the ventral and paramedian aspects of the upper brainstem (mesencephalon and pons). The pathophysiology of Duret hemorrhage remains under debate: arterial origin (stretching and laceration of pontine perforating branches of the basilar artery), versus venous origin (thrombosis and venous infarction). Multifactorial causation seems likely.

CONCLUSION

Duret hemorrhages are delayed, secondary brainstem hemorrhages. They occur in craniocerebral trauma victims with rapidly evolving descending transtentorial herniation. Diagnosis is made on computed tomography of the brain. In most cases the outcome is fatal. On the basis of our observations we believe that arterial hypertension and advanced age are risk factors for the development of Duret hemorrhage.