A hemispherotomy involves complete neural disconnection of the brain’s dysfunctional right hemisphere. The surgeon enters the brain through the right-hand side, removes (‘resects’) the temporal lobe, and then cuts through all the bundles of connections – the white-matter tracts – that link the right hemisphere with the rest of the brain and body. The isolated hemisphere remains inside the skull, and is still connected to its blood supply. It is a living but isolated island of cortex.
