Animal models for the study of intracranial hematomas (Review)

Abstract

Intracranial hematomas (ICH) are a frequent condition in neurosurgical and neurological practices, with several mechanisms of primary and secondary injury. Experimental research has been fundamental for the understanding of the pathophysiology implicated with ICH and the development of therapeutic interventions. To date, a variety of different animal approaches have been described that consider, for example, the ICH evolutive phase, molecular implications and hemodynamic changes. Therefore, choosing a test protocol should consider the scope of each particular study. The present review summarized investigational protocols in experimental research on the subject of ICH. With this subject, injection of autologous blood or bacterial collagenase, inflation of intracranial balloon and avulsion of cerebral vessels were the models identified. Rodents (mice) and swine were the most frequent species used. These different models allowed improvements on the understanding of intracranial hypertension establishment, neuroinflammation, immunology, brain hemodynamics and served to the development of therapeutic strategies.

Keywords: cerebral hemodynamics; experimental animal models; intracranial hematoma; intracranial hypertension; intracranial pressure.

Figure 1

Manuscript search and selection funneling.

Figure 2

Models, animals and outcomes assessed after an intracranial hematoma simulation.

Figure 3

Piglet surgery model with instrumentation implanted in the skull. Black star, ICP monitor with external ventricular drain; blue star, intracranial balloon; red star, transcranial Doppler probe; green star, intraparenchymal probe for ICP, brain oximetry and temperature monitoring. ICP, intracranial pressure.

Figure 4

Piglet brain after experiment with cortical injury produced by the intracranial balloon.

Figure 5

Piglet brain sagittal section after surgery. The balloon inflation produces injury by intracranial hypertension with local expansion, but not much adjacent injury. The arrow shows brain injury caused by the balloon inflation. The white stars mark the lateral ventricles of the animal.