Clinical studies on diffuse axonal injury in patients with severe closed head injury.
OBJECTIVE: To discuss the clinical criteria for diagnosing diffuse axonal injury (DAI). METHODS: Clinical and computed tomographic features of 117 patients with severe closed head injury were analyzed. The authors preliminarily put forward CT diagnostic criteria of DAI, that is, 1) single or multiple small intraparenchymal hemorrhages in the cerebral hemispheres (< 2 cm in diameter); 2) intraventricular hemorrhage; 3) hemorrhage in the corpus callosum; 4) small focal areas of hemorrhage adjacent to the third ventricle (< 2 cm in diameter); and 5) brain stem hemorrhage. All patients were divided into two groups, DAI and non-DAI group, according to the criteria. There were 42 patients in the DAI group and 75 patients in the non-DAI group. The injury causes, Glasgow coma scale (GCS) scores on admission, coexisting injuries and outcomes were compared between the two groups. The relationship between DAI and the outcomes in the patients with severe head injury was analyzed. RESULTS: Traffic accident was the main injury cause in the cases of DAI. GCS scores on admission in patients with DAI were significantly lower than those in patients without DAI. The incidence of diffuse brain swelling (DBS) in the DAI group was significantly higher than that in the non-DAI group, whereas the incidences of both skull fracture and epidural hematoma (EDH) in the DAI group were significantly lower than those in non-DAI group. There was no significant difference between the incidence of subarachnoid hemorrhage (SAH) and subdural hematoma (SDH) in the two groups. The incidence of poor outcome in the DAI group was significantly higher than that in the non-DAI group, although there was no significant difference between the mortalities in the two groups. CONCLUSIONS: Because DAI is a very important factor worsening the outcome of patients with head injury, it is essential to make a diagnosis as soon as possible. The clinical manifestations of DAI, however, are not specific and DAI does not show directly on CT scans, so it is difficult to make a definite diagnosis. The CT diagnostic criteria of DAI put forward in this article are practicable, though they are by no means perfect. (+info)
Fatal familial insomnia: clinical features and molecular genetics.
Fatal familial insomnia (FFI) is an autosomal dominant prion disease clinically characterized by inattention, sleep loss, dysautonomia, and motor signs and pathologically characterized by a preferential thalamic degeneration. FFI is linked to a missense mutation at codon 178 of the prion protein gene, PRNP, coupled with the presence of the codon methionine at position 129, the locus of a methionine-valine polymorphism. Homozygotes at codon 129, expressing methionine also in the nonmutated allele, have a shorter disease course (often less than 1 year), prominent sleep and autonomic disturbances at disease onset, and pathology restricted to the thalamus. Heterozygotes at codon 129, expressing valine in the nonmutated allele, have a longer disease course (often longer than 1 year), ataxia and dysarthria at disease onset, and lesions widespread to cerebral cortex. Both in the thalamus and in the cortex, the limbic structures are those most consistently and severely involved: the anterior ventral and mediodorsal thalamic nuclei, the cingulate gyrus, and the orbitofrontal cortex. FFI is thus a prion disease selectively damaging the thalamocortical limbic structures. Loss of sleep, sympathetic hyperactivity, and flattening of vegetative and hormonal circadian oscillations characterize FFI and result from a homeostatic imbalance caused by the interruption of the thalamocortical limbic circuits, the phylogenetically most advanced structures involved in the control of the sleep-wake cycle and the body's homeostasis. The selective atrophy of the limbic thalamus that characterizes FFI might be due to the binding of FFI toxic PrP or PrPres to specific receptors on thalamolimbic neurons. (+info)
Survey of Japanese physicians' attitudes towards the care of adult patients in persistent vegetative state.
OBJECTIVES: Ethical issues have recently been raised regarding the appropriate care of patients in persistent vegetative state (PVS) in Japan. The purpose of our study is to study the attitudes and beliefs of Japanese physicians who have experience caring for patients in PVS. DESIGN AND SETTING: A postal questionnaire was sent to all 317 representative members of the Japan Society of Apoplexy working at university hospitals or designated teaching hospitals by the Ministry of Health and Welfare. The questionnaire asked subjects what they would recommend for three hypothetical vignettes that varied with respect to a PVS patient's previous wishes and the wishes of the family. RESULTS: The response rate was 65%. In the case of a PVS patient who had no previous expressed wishes and no family, 3% of the respondents would withdraw artificial nutrition and hydration (ANH) when the patient did not require any other life-sustaining treatments, 4% would discontinue ANH, and 30% would withhold antibiotics when the patient developed pneumonia. Significantly more respondents (17%) would withdraw ANH in the case of a PVS patient whose previous wishes and family agreed that all life support be discontinued. Most respondents thought that a patient's written advance directives would influence their decisions. Forty per cent of the respondents would want to have ANH stopped and 31% would not want antibiotics administered if they were in PVS. CONCLUSIONS: Japanese physicians tend not to withdraw ANH from PVS patients. Patients' written advance directives, however, would affect their decisions. (+info)
Legal and ethical aspects of the vegetative state.
The diagnosis of persistent or permanent vegetative state (PVS) raises ethical and legal problems. Strict adherence to the doctrine of the sanctity of life would require carers to continue to maintain the individual, perhaps for many years. However, few would regard this as an appropriate outcome when the person clearly has no capacity to interact with the environment and has no likelihood of recovery. However, the ethical and legal commitment to the sanctity of life has led courts to employ a variety of approaches to this situation in order to find a way in which the person in PVS can be allowed to die. It is argued that each of the approaches is disingenuous and ultimately unhelpful. What the law is doing is endorsing non-voluntary euthanasia, but dressing it up as something else. This is unhelpful for all concerned and the time has come for a review of all end of life decisions so that doctors, patients, and relatives can make honest decisions without fear of legal reprisal. (+info)
The neuropathology of the vegetative state after an acute brain insult.
The vegetative state is often described clinically as loss of function of the cortex while the function of the brainstem is preserved. In an attempt to define the structural basis of the vegetative state we have undertaken a detailed neuropathological study of the brains of 49 patients who remained vegetative until death, 1 month to 8 years after an acute brain insult. Of these, 35 had sustained a blunt head injury and 14 some type of acute non-traumatic brain damage. In the traumatic cases the commonest structural abnormalities identified were grades 2 and 3 diffuse axonal injury (25 cases, 71%). The thalamus was abnormal in 28 cases (80%), and in 96% of the cases who survived for more than 3 months. Other abnormalities included ischaemic damage in the neocortex (13 cases, 37%) and intracranial haematoma (nine cases, 26%). In the non-traumatic cases there was diffuse ischaemic damage in the neocortex in nine cases (64%) and focal damage in four (29%); the thalamus was abnormal in every case. There were cases in both groups where the cerebral cortex, the cerebellum and the brainstem were of structurally normal appearance. In every case, however, there was profound damage to the subcortical white matter or to the major relay nuclei of the thalamus, or both. These lesions render any structurally intact cortex unable to function because connections between different cortical areas via the thalamic nuclei are no longer functional, and there is also extensive damage to afferent and efferent cerebral connections. (+info)
Auditory processing in the vegetative state.
H(2)(15)O-PET was used to investigate changes in regional cerebral blood flow in response to auditory stimulation in patients in the vegetative state. Five patients in a vegetative state of hypoxic origin were compared with 18 age-matched controls. In addition, the cerebral metabolism of these patients and 53 age-matched controls was studied using [(18)F]fluorodeoxyglucose. In control subjects, auditory click stimuli activated bilateral auditory cortices [Brodmann areas (BA) 41 and 42] and the contralateral auditory association cortices (BA 22). In the patients, although resting metabolism was decreased to 61% of normal values, bilateral auditory areas 41 and 42 showed activation as seen in the controls, but the temporoparietal junction cortex (BA 22) failed to be activated. Moreover, the auditory association cortex was functionally disconnected from the posterior parietal association area (BA 40), the anterior cingulate cortex (BA 24) and the hippocampus, as revealed by psychophysiological interaction analysis. Thus, despite altered resting metabolism, the auditory primary cortices were still activated during external stimulation, whereas hierarchically higher-order multi- modal association areas were not. Such a cascade of functional disconnections along the auditory cortical pathways, from the primary auditory areas to multimodal and limbic areas, suggests that the residual cortical processing observed in the vegetative state cannot lead to the integrative processes that are thought to be necessary for the attainment of the normal level of awareness. (+info)
Anaesthetic management of a pregnant patient in a persistent vegetative state.
Pregnancy in a patient in a persistent vegetative state presents challenging therapeutic questions about the level of supportive management required, the assessment of fetal well-being, the timing and mode of delivery and the anaesthetic management of labour and delivery. We report the case of a 29-yr-old woman who had a favourable fetal outcome despite suffering hypoxic brain damage after a suicide attempt by a drug overdose. She was managed until the onset of labour on an intensive care unit and had a spontaneous vaginal delivery assisted by epidural anaesthesia. (+info)
Late occurrence of diffuse cerebral swelling after intracerebral hemorrhage in a patient with the HELLP syndrome--Case report.
Hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome can occur at any time in the course of pregnancy and is associated with many complications including fatal stroke. A 37-year-old female presented with HELLP syndrome causing an intracerebral hematoma, which was treated by evacuation and mild hypothermia. Unexpected diffuse cerebral swelling occurred on the 15th day of the initially favorable postoperative course. Considerable impairment of consciousness persisted despite conservative therapy. Serial computed tomographic findings indicated delayed cerebral vasospasm as the cause of the swelling. Particularly careful management is required even beyond the first 2 weeks for patients with stroke as a complication of HELLP syndrome. (+info)