Table 1 Diagnostic and prognostic use of instrumental tools recommendations in patients with disorders of consciousness
Guideline | Recommendation no. | Recommendation | Prognosis/diagnosis | Level of recommendations |
|---|---|---|---|---|
AAN | 2e | In situation where there is continued ambiguity regarding evidence of conscious awareness despite serial neurobehavioral assessments, or where confounders to a valid clinical diagnostic assessment are identified, clinicians may use multimodal evaluations incorporating specialized functional imaging or electrophysiologic studies to assess for evidence of awareness not identified on neurobehavioral assessment that might prompt consideration of an alternate diagnosis | Diagnosis | C (weak) |
5 | In post-traumatic VS/UWS patients, clinicians [..] may assess for the presence of P300 at 2–3 months post-injury or assess EEG reactivity at 2–3 months post-injury to assist in prognostication regarding 12-month recovery of consciousness for patients in traumatic VS/UWS | Prognosis | C (weak) | |
In post-traumatic VS/UWS patients, clinicians should perform MRI 6–8 weeks post-injury to assess for corpus callosal lesions, dorsolateral upper brainstem injury, or corona radiata injury in order to assist in prognostication regarding remaining in PVS at 12 months for patients in traumatic VS/UWS | Prognosis | B (moderate) | ||
In post-traumatic VS/UWS patients, clinicians should perform a SPECT scan 1–2 months post-injury to assist in prognostication regarding 12-month recovery of consciousness and degree of disability/recovery for patients in traumatic VS/UWS | Prognosis | B (moderate) | ||
In post-traumatic VS/UWS patients, clinicians may assess for the presence of higher-level activation of the auditory association cortex using BOLD fMRI in response to a familiar voice speaking the patient’s name to assist in prognostication regarding 12-month (post-scan) recovery of consciousness for patients in traumatic VS/UWS 1–60 months post-injury | Prognosis | C (weak) | ||
6 | In non-traumatic post-anoxic VS/UWS patients, clinicians [..] may assess SEPs to assist in prognostication regarding recovery of consciousness at 24 months | Prognosis | C (weak) | |
EAN | Functional neuroimaging | |||
PICO 1 | Resting-state fluorodeoxyglucose (FDG) PET may be considered as part of multimodal assessment in unresponsive patients | Diagnosis | Low evidence, weak recommendation | |
PICO 2 | If a standard clinical (structural) MRI is indicated, it is suggested that a resting-state fMRI sequence is added as part of multimodal assessment | Diagnosis | Low evidence, weak recommendation | |
PICO 3 | It is suggested to add a resting-state fMRI sequence as part of multimodal assessment whenever a standard (structural) MRI is indicated; however, the default mode network is just one of several resting-state fMRI networks that may be used to complement the behavioral assessment in patients with DOC | Diagnosis | Low evidence, weak recommendation | |
PICO 4 | It is suggested that passive fMRI paradigms be used within research protocols | Diagnosis | Low evidence, weak recommendation | |
PICO 5 | It is suggested that active fMRI paradigms should be considered as part of multimodal assessment in patients without command following at the bedside | Diagnosis | Moderate evidence, weak recommendation | |
PICO 6 | It is therefore suggested that salient stimuli should be used for examination of DOC patients by fMRI | Diagnosis | Very low evidence, weak recommendation | |
EEG-based techniques, including TMS-EEG and evoked potentials | ||||
PICO 1 | Visual analysis of clinical standard EEG seems to detect patients with preserved consciousness with high specificity but low sensitivity | Diagnosis | Low evidence, strong recommendation | |
PICO 2 | Non-visual (i.e. numerical) analysis of standard EEG cannot yet be recommended for the differentiation between VS/UWS and MCS | Diagnosis | Very low evidence, weak recommendation | |
PICO 3 | It is suggested that sleep EEG be used for the differentiation between VS/UWS and MCS as a part of multimodal assessment | Diagnosis | Low evidence, weak recommendation | |
PICO 4 | It is suggested that quantitative analysis of high-density EEG be considered for the differentiation between VS/UWS and MCS as part of multimodal assessment | Diagnosis | Moderate evidence, weak recommendation | |
PICO 5 | Cognitive evoked potentials for the differentiation between VS/UWS and MCS might be considered as part of multimodal assessment | Diagnosis | Low evidence, weak recommendation | |
PICO 6 | It is suggested that TMS-EEG should be considered for the differentiation between VS/UWS and MCS as part of multimodal assessment | Diagnosis | Low evidence, weak recommendation | |
RCP | 2.7 | It is not yet clear whether more sophisticated electrophysiology and brain imaging techniques (e.g., fMRI, PET, DTI) have any diagnostic or prognostic utility over and above expert clinical and behavioral assessment | Diagnosis and prognosis | E1/2 |
(a) They do not form part of the standard assessment battery for PDOC at the current time, nor do they represent a ‘practicable step’ required by s.1(3) MCA 2005 to support a person’s capacity to make relevant decisions | ||||
(b) Further work is required to understand the relationship between these and the formal clinical evaluation tests | ||||
(c) In the meantime, they should be only applied in the context of a registered research program and in conjunction with formal clinical evaluation as described in recommendation 2.4 | ||||