Investigating the Localization of Consciousness Through Patients with Disorders of Consciousness: Anterior Vs. Posterior Cortex Debate

Patients enrolled in the study underwent five assessments using the CRS-R (Coma Recovery Scale-Revised) within 10 days, along with an 18F-FDG-PET (18F-fluorodeoxyglucose-positron emission tomography) scan. The CRS-R evaluations were conducted by professionally trained and highly experienced personnel. During the CRS-R assessments, patients' behavioral responses were recorded in the domains of visual, auditory, motor, oromotor/verbal, communication, and arousal. Based on the optimal CRS-R results obtained within the 10-day period, patients were categorized into MCS (Minimally consciousness state, criteria: consistent command-following, reproducible responses to commands, object recognition, intelligible verbalization, partially accurate communication, object localization, visual pursuit and visual object localization, spontaneous motor responses, object manipulation, and/or localization to noxious stimulation) or UWS (Unresponsive wakefulness syndrome, criteria: preserved wakefulness accompanied by behavioral responses such as localization to sound, auditory startle, visual startle, withdrawal/flexion movements, abnormal posturing, vocalizations/oromotor movements, and reflexive oromotor responses). All patients exhibited stable vital signs. For data analysis, a healthy control group from Belgium was included to compare brain metabolism between patients with disorders of consciousness and healthy individuals.

Inclusion criteria

• Confirmed diagnosis of disorders of consciousness after 5 CRS-R assessments;
• Age >18 years;
• Stable vital signs;
• No use of sedatives or neuromuscular blockers within 24 hours prior to enrollment.

Exclusion criteria

• Acute-phase patients (injury duration <28 days);
• Fewer than 5 CRS-R assessments completed within 10 days;
• Patients diagnosed with EMCS (Emerging Minimally Conscious State);
• Patients with unclear diagnoses (cases where experienced evaluators could not reach a consensus diagnosis);
• Patients with persistent seizures.