From connectome mapping to surgical interventions

This 15-minute session will give a brief introduction to use of intra-cerebral depth electrode recording using stereoelectroencephalography (stereo-EEG, SEEG) for presurgical evaluation of focal drug-resistant epilepsy, in conjunction with other structural and functional imaging modalities. An illustrative case will be shown of a patient with frontal lobe epilepsy in whom multi-modal and quantified analysis of the epileptogenic zone network helped to guide surgical decision making for treating refractory hyperkinetic seizures.  

Enormous sums of tax payer dollars have been aimed at neuroimaging based research with the hope of providing new treatments and related insights. Despite the efforts of ten of thousands over 3 decades, until the past few years, using fMRI clinically required having one of those people do it for you, which is not scalable or useful. In this talk, I will outline our efforts over the past 7 years to bring a connectomic medical device in the market and to train people how to use it. In this,we will talk about product creation, insights into what the field needs to do, and the direction we see this heading in the next few years. 

Cognition and behaviour are thought to be underpinned by seven segregated brain networks, ranging from the sensory functions of the visual network to the intrinsic mental processes, such as consciousness, associated with the default-mode network. However, it remains uncertain whether the functional integrity of these networks persists when the brain is devoid of external inputs. To explore this, we examine the functional organization of individual brain hemispheres in individuals who have undergone hemispherotomy for pharmacoresistant epilepsy. Our findings reveal that the intrinsic functional organization of the seven hierarchically ordered macroscale networks is preserved in the isolated hemisphere after hemispherotomy. However, both isolated and connected hemispheres exhibit reduced network segregation and higher interindividual variability compared to healthy brains. These results suggest that isolated hemispheres retain functional integrity, prompting further exploration into their cognitive capabilities and their potential to be “islands of awareness”.
 

In this translational presentation, Dr. Holanda describes how she integrates her neurosurgical practice with anatomical research, including the dissection of white matter in postmortem brains using Klingler’s method.