Transcranial color Doppler sonography in the emergency diagnosis of middle cerebral artery occlusion in a patient after head injury

Fast synchronized dual-wavelength laser speckle imaging system for monitoring hemodynamic changes in a stroke mouse model

In this Letter, we describe a newly developed synchronized dual-wavelength laser speckle contrast imaging system, which contains two cameras that are synchronously triggered to acquire data. The system can acquire data at a high spatiotemporal resolution (up to 500 Hz for ~1000×1000 pixels). A mouse model of stroke is used to demonstrate the capability for imaging the fast changes (within tens of milliseconds) in oxygenated and deoxygenated hemoglobin concentration, and the relative changes in blood flow in the mouse brain, through an intact cranium. This novel imaging technology will enable the study of fast hemodynamics and metabolic changes in vascular diseases.

A new method for the early diagnosis of brain edema/brain swelling. An experimental study in rabbits

The aim of the present work is to develop a non-destructive, non-invasive technique for the early diagnosis of an oncoming brain edema based on the variation of vibration characteristics of the head system (i.e. eigenfrequency spectrum and modal damping). Besides the theoretical model that supports the basic principle, the proposed technique has been verified experimentally in animal tests. The advantage of such an approach is that the relative information is available well in advance an increase of intracranial pressure is detected. The uncontrolled intracranial hypertension is associated with increased mortality or vegetative state in head trauma. Traumatic lesions located on temporal lobe render particularly impeding the transtendorial herniation. From the medical point of view, intracranial pressure (ICP) monitoring represents an effective way for early consideration of neurological decompensation in various neurosurgical conditions particularly in the head-injured setting. However, the use of ICP monitoring is not an effective way of brain edema detection, since ICP increase very often causes irreversible problems to the patient's brain. Therefore, the determination of an earlier, less invasive and more sensitive indicator of the oncoming intracranial hypertension and of the impeding neurological deterioration is of profound importance. The present work aims at experimental verification of both eigenfrequency shifting and modal damping increase of the spectral response of the head system of rabbits, wherever a mass increase in the content of cranial shell appears. The conducted analysis concludes that the eigenfrequency spectrum and its modal damping characteristics are sufficiently sensitive parameters in order to characterize mass increase in the cranial shell. Therefore the combination of both the above parameters could be used with confidence for the early diagnosis of brain edema.