Light, Kindling, Action! Brain-Wide Circuit Changes After Optogenetic Hippocampal Kindling Revealed by Functional Magnetic Resonance Imaging

Neurophotonic methods in approach to in vivo animal epileptic models: Advantages and limitations

Neurophotonic technology is a rapidly growing group of techniques that are based on the interactions of light with natural or genetically modified cells of the neural system. New optical technologies make it possible to considerably extend the tools of neurophysiological research, from the visualization of functional activity changes to control of brain tissue excitability. This opens new perspectives for studying the mechanisms underlying the development of human neurological diseases. Epilepsy is one of the most common brain disorders; it is characterized by recurrent seizures and affects >1% of the world's population. However, how seizures occur, spread, and terminate in a healthy brain is still unclear. Therefore, it is extremely important to develop appropriate models to accurately explore the causal relationship of epileptic activity. The use of neurophotonic technologies in epilepsy research falls into two broad categories: the visualization of neural epileptic activity, and the direct optical influence on neurons to induce or suppress epileptic activity. An optogenetic variant of the classical kindling model of epileptic seizures, in which activatable cells are genetically defined, is called optokindling. Research is also underway concerning the application of neurophotonic techniques for suppressing epileptic activity, aiming to bring these methods into clinical practice. This review aims to systematize and describe new approaches that use combinations of different neurophotonic methods to work with in vivo models of epilepsy. These approaches overcome many of the shortcomings associated with classical animal models of epilepsy and thus increase the effectiveness of developing new diagnostic methods and antiepileptic therapy.

Increased seizure frequency in an epilepsy patient receiving medium cut-off dialysis

This paper presents the case of a male dialysis patient, with generalised epilepsy, who experienced complications after starting medium cut-off (MCO) dialysis. While receiving haemodiafiltration, the patient's epilepsy had been relatively well controlled using two antiseizure medications (brivaracetam and sodium valproate). However, the patient's seizure frequency increased when he was changed to MCO dialysis. MCO is a new dialysis method that has been developed to allow for better clearance of uraemic toxins through its larger pore size. We hypothesise that using the highly permeable MCO membrane changed the seizure threshold by an unknown mechanism. This is the first reported case to observe increased seizure frequency in a patient receiving MCO dialysis. The case highlights the need for caution when prescribing dialysis methods to patients with epilepsy.