James L.Bernat, Dartmouth-Hitchcock Medical Centerbernat@dartmouth.edu
James L. Bernat, Lebanon, NH
Submitted January 02, 2013
The article by Yu and colleagues1 contributes several additional cases of
patients diagnosed in a vegetative state (unresponsive wakefulness
syndrome) by clinical criteria but who have shown fMRI or processed EEG
responses indicating awareness, and therefore should be diagnosed
correctly as in a minimally conscious state. These cases and similar ones
published previously show that the neurological examination alone may, in
some cases, be insensitive to detect the presence of awareness. The
medical and ethical importance of this finding has been emphasized in
numerous publications over the past six years. [2-4]
The impact of functional neuroimaging in showing the limitations of
the neurological examination to detect awareness is reminiscent of the
earlier impact of DNA genetic studies in showing the limitation of the
clinical phenotypic classification of neurogenetic syndromes.
What would be most useful at this point is for one of the
investigators to collect all the cases in which the neurological
examination has been found inadequate to assess awareness and contrast
them with the majority of cases in which the clinical examination was
accurate. Perhaps there are common features of the clinically misdiagnosed
cases that could inform our understanding of awareness with and without
responsiveness.
James L. Bernat, M.D.
Dartmouth-Hitchcock Medical Center
Lebanon, NH 03756
1. Yu T, Lang S, Vogel D, et al. Patients with unresponsive
wakefulness syndrome respond to the pain cries of other people. Neurology
2013;80:1-8.
2. Coleman MR, Davis MH, Rodd JM, et al. Toward the routine use of brain imaging to aid the clinical diagnosis of disorders of consciousness. Brain 2009;132:2541-2552.
3. Wilkinson DJ, Kahane G, Horne M, Savulescu J. Functional neuroimaging and withdrawal of life-sustaining therapy from vegetative patients. J Med Ethics 2009;35:508-511.
4. Bernat JL. Current controversies in states of chronic unconsciousness. Neurology 2010;75 (Suppl 1): S33-S38.
The article by Yu and colleagues1 contributes several additional cases of patients diagnosed in a vegetative state (unresponsive wakefulness syndrome) by clinical criteria but who have shown fMRI or processed EEG responses indicating awareness, and therefore should be diagnosed correctly as in a minimally conscious state. These cases and similar ones published previously show that the neurological examination alone may, in some cases, be insensitive to detect the presence of awareness. The medical and ethical importance of this finding has been emphasized in numerous publications over the past six years. [2-4]
The impact of functional neuroimaging in showing the limitations of the neurological examination to detect awareness is reminiscent of the earlier impact of DNA genetic studies in showing the limitation of the clinical phenotypic classification of neurogenetic syndromes.
What would be most useful at this point is for one of the investigators to collect all the cases in which the neurological examination has been found inadequate to assess awareness and contrast them with the majority of cases in which the clinical examination was accurate. Perhaps there are common features of the clinically misdiagnosed cases that could inform our understanding of awareness with and without responsiveness.
James L. Bernat, M.D. Dartmouth-Hitchcock Medical Center Lebanon, NH 03756
1. Yu T, Lang S, Vogel D, et al. Patients with unresponsive wakefulness syndrome respond to the pain cries of other people. Neurology 2013;80:1-8.
2. Coleman MR, Davis MH, Rodd JM, et al. Toward the routine use of brain imaging to aid the clinical diagnosis of disorders of consciousness. Brain 2009;132:2541-2552.
3. Wilkinson DJ, Kahane G, Horne M, Savulescu J. Functional neuroimaging and withdrawal of life-sustaining therapy from vegetative patients. J Med Ethics 2009;35:508-511.
4. Bernat JL. Current controversies in states of chronic unconsciousness. Neurology 2010;75 (Suppl 1): S33-S38.