title: Results of a prospective study (CATS) on the effects of thalamic stimulation in minimally conscious and vegetative state patients.
abstract: OBJECTIVE Deep brain stimulation of the thalamus was introduced more than 40 years ago with the objective of improving the performance and attention of patients in a vegetative or minimally conscious state. Here, the authors report the results of the Cortical Activation by Thalamic Stimulation (CATS) study, a prospective multiinstitutional study on the effects of bilateral chronic stimulation of the anterior intralaminar thalamic nuclei and adjacent paralaminar regions in patients affected by a disorder of consciousness. METHODS The authors evaluated the clinical and radiological data of 29 patients in a vegetative state (unresponsive wakefulness syndrome) and 11 in a minimally conscious state that lasted for more than 6 months. Of these patients, 5 were selected for bilateral stereotactic implantation of deep brain stimulating electrodes into their thalamus. A definitive consensus for surgery was obtained for 3 of the selected patients. All 3 patients (2 in a vegetative state and 1 in a minimally conscious state) underwent implantation of bilateral thalamic electrodes and submitted to chronic stimulation for a minimum of 18 months and a maximum of 48 months. RESULTS In each case, there was an increase in desynchronization and the power spectrum of electroencephalograms, and improvement in the Coma Recovery Scale-Revised scores was found. Furthermore, the severity of limb spasticity and the number and severity of pathological movements were reduced. However, none of these patients returned to a fully conscious state. CONCLUSIONS Despite the limited number of patients studied, the authors confirmed that bilateral thalamic stimulation can improve the clinical status of patients affected by a disorder of consciousness, even though this stimulation did not induce persistent, clinically evident conscious behavior in the patients. Clinical trial registration no.: NCT01027572 ( ClinicalTrials.gov ).
authors.affiliation: Neurochirurgia Dipartimento di Scienze Clinico-Chirurgiche, Diagnostiche e Pediatriche, University of Pavia-Fondazione IRCCS Policlinico S. Matteo, Pavia.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Magrassi
authors.affiliation: Neurorehabilitation Unit, Salvatore Maugeri Foundation IRCCS, Scientific Institute of Pavia.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Maggioni
authors.affiliation: Neurorehabilitation Unit, Salvatore Maugeri Foundation IRCCS, Scientific Institute of Pavia.
authors.forename: Caterina
authors.initials: C
authors.lastname: Pistarini
authors.affiliation: Neuroradiology Unit, Neurological Institute IRCCS Fondazione C. Mondino, Pavia, Italy.|Coma Science Group, Cyclotoron Research Center, University of Liege, Belgium.
authors.forename: Carol
authors.initials: C
authors.lastname: Di Perri
authors.affiliation: Neuroradiology Unit, Neurological Institute IRCCS Fondazione C. Mondino, Pavia, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Bastianello
authors.affiliation: Istituto di Bioimmagini e Fisiologia Molecolare, CNR, Segrate; and.
authors.forename: Antonio G
authors.initials: AG
authors.lastname: Zippo
authors.affiliation: Rianimazione 2° and.
authors.forename: Giorgio A
authors.initials: GA
authors.lastname: Iotti
authors.affiliation: Istituto di Bioimmagini e Fisiologia Molecolare, CNR, Segrate; and.
authors.forename: Gabriele E M
authors.initials: GE
authors.lastname: Biella
authors.affiliation: Rianimazione 2° and.|Phase I Clinical Trial Unit and Experimental Therapy, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Imberti
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D046690:Deep Brain Stimulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018458:Persistent Vegetative State / Q000628:therapy*; D011446:Prospective Studies; D013788:Thalamus; D014474:Unconsciousness / Q000628:therapy*; D055815:Young Adult
keywords: CATS = Cortical Activation by Thalamic Stimulation; CRS-R = Coma Recovery Scale Revised; DBS = deep brain stimulation; DOC = disorder of consciousness; EEG = electroencephalographic; ICA = independent component analysis; IRCCS = Istituto Ricerca Cura Carattere Scientifico; MCS = minimally conscious state; UMRS = Unified Myoclonus Rating Scale; VS/UWS = vegetative state/unresponsive wakefulness syndrome; deep brain stimulation; fMRI = functional MRI; minimally conscious state; thalamic stimulation; unresponsive wakefulness syndrome; vegetative state