Delayed postanoxic encephalopathy after strangulation. Serial neuroradiological and neurochemical studies

Spectrum of delayed post-hypoxic leukoencephalopathy syndrome: A systematic review

BACKGROUND

Delayed post hypoxic leukoencephalopathy syndrome (DPHLS), also known as Grinker's myelinopathy, is a rare but significant neurological condition that manifests days to weeks after a hypoxic event. Characterized by delayed onset of neurological and cognitive deficits, DPHLS presents substantial diagnostic and therapeutic challenges.

AIM

To consolidate current knowledge on pathophysiology, clinical features, diagnostic approaches, and management strategies for DPHLS, providing a comprehensive overview and highlighting gaps for future research.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines, we systematically searched PubMed, ScienceDirect and Hinari databases using terms related to delayed post-hypoxic leukoencephalopathy. Inclusion criteria were original research articles, case reports, and case series involving human subjects with detailed clinical, neuroimaging, or pathological data on DPHLS. Data were extracted on study characteristics, participant demographics, clinical features, neuroimaging findings, pathological findings, treatment, and outcomes. The quality assessment was performed using the Joanna Briggs Institute critical appraisal checklist.

RESULTS

A total of 73 cases were reviewed. Common comorbidities included schizoaffective disorder, bipolar disorder, hypertension, and substance use disorder. The primary causes of hypoxia were benzodiazepine overdose, opioid overdose, polysubstance overdose, and carbon monoxide (CO) poisoning. Symptoms frequently include decreased level of consciousness, psychomotor agitation, cognitive decline, parkinsonism, and encephalopathy. Neuroimaging commonly revealed diffuse T2 hyperintensities in cerebral white matter, sometimes involving the basal ganglia and the globus pallidus. Magnetic resonance spectroscopy often showed decreased N-acetylaspartate, elevated choline, choline-to-creatinine ratio, and normal or elevated lactate. Treatment is often supportive, including amantadine, an antioxidant cocktail, and steroids. Hyperbaric oxygen therapy may be beneficial in those with CO poisoning. Parkinsonism was often treated with levodopa. Most of the patients had substantial recovery over the course of months and many cases had some residual neurocognitive deficits.

CONCLUSION

DPHLS remains a complex and multifaceted condition with various etiologies and clinical manifestations. Early recognition and appropriate management are crucial to improving patient outcomes. Future research should focus on standardizing diagnostic criteria, using advanced imaging techniques, and exploring therapeutic interventions to improve understanding and treatment of DPHLS. Conducting prospective cohort studies and developing biomarkers for early diagnosis and monitoring will be essential to advance patient care.

Akinetic mutism and gait disturbance in a patient with delayed post-hypoxic leukoencephalopathy

We report on a patient with delayed post-hypoxic leukoencephalopathy (DPHL) who showed akinetic mutism and gait disturbance, neural injuries that were demonstrated on diffusion tensor tractography (DTT). A patient was exposed to carbon monoxide (CO) and rapidly recovered; however, two weeks after onset, he began to show cognitive impairment and gait disturbance. At six weeks after CO exposure, he showed akinetic mutism and gait inability. DTT at 6-weeks post-exposure showed discontinuations in neural connectivities of the caudate nucleus to the medial prefrontal and orbitofrontal cortex in both hemispheres. In addition, the corticoreticulospinal tract revealed severe thinning in both hemispheres.

Pre- and post-conditioning with poly I:C exerts neuroprotective effect against cerebral ischemia injury in animal models: A systematic review and meta-analysis

BACKGROUND

Toll-like receptor (TLR) agonist polyinosinic-polycytidylic acid (poly I:C) exerts neuroprotective effects against cerebral ischemia (CI), but concrete evidence supporting its exact mechanism of action is unclear.

METHODS

We evaluated the neuroprotective role of poly I:C by assessing CI indicators such as brain infarct volume (BIV), neurological deficit score (N.S.), and signaling pathway proteins. Moreover, we performed a narrative review to illustrate the mechanism of action of TLRs and their role in CI. Our search identified 164 articles and 10 met the inclusion criterion.

RESULTS

Poly I:C reduces BIV and N.S. (p = 0.00 and p = 0.03). Interestingly, both pre- and post-conditioning decrease BIV (preC p = 0.04 and postC p = 0.00) and N.S. (preC p = 0.03 and postC p = 0.00). Furthermore, poly I:C upregulates TLR3 [SMD = 0.64; CIs (0.56, 0.72); p = 0.00], downregulates nuclear factor-κB (NF-κB) [SMD = -1.78; CIs (-2.67, -0.88); p = 0.0)], and tumor necrosis factor alpha (TNF-α) [SMD = -16.83; CIs (-22.63, -11.02); p = 0.00].

CONCLUSION

We showed that poly I:C is neuroprotective and acts via the TLR3/NF-κB/TNF-α pathway. Our review indicated that suppressing TLR 2/4 may illicit neuroprotection against CI. Further research on simultaneous activation of TLR3 with poly I:C and suppression of TLR 2/4 might open new vistas for the development of therapeutics against CI.

Neurodegenerative effect of DAPK1 after cerebral hypoxia-ischemia is associated with its post-transcriptional and signal transduction regulations: A systematic review and meta-analysis

Cerebral hypoxia-ischemia (CHI) causes brain aging, neurological disorders, cognitive decline, motor function impairment, and mortality. Inhibiting death-associated protein kinase 1 (DAPK1) has shown therapeutic potential against CHI, but several reports contradict its protective function, mechanism of activation, and signal transduction. Here, we systematically reviewed the role and the activation mechanism of DAPK1, and quantitatively assess the efficacy of DAPK1 inhibition (DI) methods in neuroprotection, following a CHI in animal models. Embase and PubMed were searched for relevant studies. Overall, 13 studies met the inclusion criteria, and the SYRCLE Risk of bias tool (RoB) tool was used to assess RoB. StataSE 16 was used for meta-analysis and network meta-analysis (NMA). Standardized mean differences (SMD) with 95% confidence intervals (CI) were calculated to estimate the effect size. DI was associated with the reduction of brain infarct volume (BIV) [SMD = -1.70, 95% CI (-2.10, -1.30); p = 0.00], neurological score (N.S.), neuronal degeneration, with no change in the level of in cell death [SMD = -0.83, 95% CI (-2.00, 0.35); p = 0.17], indicating the protective role of DI against CHI. No differences were found in DAPK1 mRNA and protein levels [SMD = 0.50, 95% CI (-0.05, 1.04); p = 0.07] {single-study driven; upregulated after exclusion (p = 0.01, I² = 36.43)}, whereas phospho-DAPK1 [SMD = -2.22, 95% CI (-3.69, -0.75); p = 0.00] was downregulated and phosphorylated myosin light chain [SMD = 3.37, 95% CI (2.51, 4.96); p = 0.00] was upregulated between CHI and sham groups. Furthermore, we performed NMA to understand the molecular level at which DI offers maximum protection against BIV. Post-transcriptional inhibition (PTI; SUCRA, 82.6%) and gene knockout showed best (KO; SUCRA, 81.3%), signal transduction inhibition (STI; SUCRA, 49.5%) offered 3^rd best, while catalytic activity inhibition (CAI; SUCRA, 0.3%) exhibited the lowest reduction in BIV against CHI. The results demonstrate that DI has a neuroprotective effect against CHI and DAPK1 might be regulated at the post-transcriptional and post-translational levels after CHI. Inhibiting DAPK1 at the post-transcriptional level and blocking multiple signal transduction pathways of DAPK1 could lead to better functional recovery against CHI. AVAILABILITY OF DATA AND MATERIALS: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Parenchymal brain injuries in abusive head trauma

The consequences of abusive head trauma (AHT) can be devastating for both the individual child and for wider society. Death is undoubtedly a very real possibility, but even for those children who survive, there is often very significant morbidity with the potential for gross motor and cognitive impairment, behavioural problems, blindness and epilepsy, which can greatly affect their quality of life. Caring for such children places a vast financial and infrastructural burden on society that frequently extends well into adulthood. While few struggle to have any sympathy for the perpetrator, frequently the infant's father, it should be noted that a single solitary and momentary loss of complete control can have horrific and unforeseen consequences. A number of papers within this edition describe features of AHT and include descriptions of skull fractures and extra-axial haemorrhage, along with mimics of such phenomena. However, in this review we concentrate our attention on the myriad of parenchymal findings that can occur. Such parenchymal injuries include hypoxic-ischaemic damage, clefts, contusion and focal haemorrhage. We offer our perspectives on current thinking on these entities and put them in the context of the immensely important question - how do we recognise abusive head trauma?

Neck-MRI experience for investigation of survived strangulation victims

For the medicolegal evaluation of victims of survived strangulation, a neck-magnetic resonance imaging (MRI) can be performed for assessing lesions in the inner soft tissues (fat, muscles or lymph nodes, for example). In our institute, such MRI examinations have been performed for a test period of 4 years with the aim of evaluating the use of this tool by forensic pathologists and identifying medicolegal indicators for the performance of neck-MRI in surviving victims of strangulation. We retrospectively reviewed medicolegal reports from all victims examined during the test period. We extracted objective lesions (e.g. petechiae, bruising and abrasions) and reported clinical symptoms (e.g. vision disorder, dysphasia) from the reports. These findings were compared to those reported from the neck-MRI. In total, 112 victims were clinically examined after suspected strangulation. Eleven of these victims underwent an MRI examination of the neck. Eighty-four of the victims presented objective lesions during the clinical examination, with eight showing signs of both petechiae and bruising. Neck-MRI was performed in four of these eight victims and three of them showed lesions visible in MRI. Of 76 victims with bruising as the only objective finding, 66 victims described clinical symptoms. Of those 66 victims, seven were examined by MRI and two demonstrated lesions in MRI. When MRI was performed, relevant findings were detected in 45% of the cases. This leads to the suspicion that many more findings could have been detected in the other victims, if an MRI had been performed in those cases. Our results lead us to the conclusion that an MRI examination of victims of suspected strangulation is useful, and strict indications for its application should be established.

Clemastine rescues myelination defects and promotes functional recovery in hypoxic brain injury

Hypoxia can injure brain white matter tracts, comprised of axons and myelinating oligodendrocytes, leading to cerebral palsy in neonates and delayed post-hypoxic leukoencephalopathy (DPHL) in adults. In these conditions, white matter injury can be followed by myelin regeneration, but myelination often fails and is a significant contributor to fixed demyelinated lesions, with ensuing permanent neurological injury. Non-myelinating oligodendrocyte precursor cells are often found in lesions in plentiful numbers, but fail to mature, suggesting oligodendrocyte precursor cell differentiation arrest as a critical contributor to failed myelination in hypoxia. We report a case of an adult patient who developed the rare condition DPHL and made a nearly complete recovery in the setting of treatment with clemastine, a widely available antihistamine that in preclinical models promotes oligodendrocyte precursor cell differentiation. This suggested possible therapeutic benefit in the more clinically prevalent hypoxic injury of newborns, and we demonstrate in murine neonatal hypoxic injury that clemastine dramatically promotes oligodendrocyte precursor cell differentiation, myelination, and improves functional recovery. We show that its effect in hypoxia is oligodendroglial specific via an effect on the M1 muscarinic receptor on oligodendrocyte precursor cells. We propose clemastine as a potential therapy for hypoxic brain injuries associated with white matter injury and oligodendrocyte precursor cell maturation arrest.

Delayed Post-hypoxic Leukoencephalopathy: A Case Series and Review of the Literature

Delayed post-hypoxic leukoencephalopathy (DPHL) is a unique clinical entity that presents with cognitive impairment days to weeks after an episode of acute hypoxic brain injury. Frequently hypoxia is unrecognized as a mechanism for clinical decline and extensive workup ensues. We present two cases of DPHL highlighting the neuroimaging findings. In both patients, a cerebral hypoxic event was followed by a recovery phase with subsequent delayed clinical decline. Patient 1 suffered hypoxia from drug-induced respiratory depression and lack of post-operative positive airway pressure (PAP) support. Her neurological exam on follow-up revealed progressive cognitive decline. Magnetic resonance imaging (MRI) brain showed bilateral white matter changes involving the centrum semiovale. Patient 2 developed a generalized tonic-clonic seizure during an endobronchial biopsy procedure and was found to have multiple air emboli on computed tomography (CT) head scan. She was initially in a drug-induced coma for her seizures. Electroencephalography (EEG) on day 14 of admission showed changes consistent with diffuse encephalopathy. MRI brain showed bilateral white matter changes particularly at the watershed zones and in the centrum semiovale. DPHL is a rare and under-recognized clinical entity that requires clinical suspicion and detailed evaluation for diagnosis. Neuroimaging studies can provide prognostic information regarding the extent of neurological injury.

Differentiating among Attempted, Completed, and Multiple Nonfatal Strangulation in Women Experiencing Intimate Partner Violence

PURPOSE

Because identification of intimate partner violence (IPV) in health care settings is low and strangulation increases lethality risk among women experiencing IPV, we examined the prevalence and correlates of nonfatal strangulation among 1,008 women survivors of IPV.

METHODS

Trained researchers conducted semistructured interviews with women survivors of IPV referred by police. Multinomial logistic regression examined differential correlates of attempted, completed, and multiple strangulation.

RESULTS

Interviews were conducted with 71.14% of eligible women contacted by researchers. A high proportion (79.66%) of the women interviewed experienced attempted (11.70%), completed (30.16%), or multiple (37.80%) strangulation. Each form of strangulation was independently significantly associated with sexual violence when compared with no strangulation. African American women were at increased risk of attempted (adjusted relative risk ratio [ARR], 2.02; p < .05), completed (ARR, 1.79; p < .05), and multiple strangulation (ARR, 2.62; p < .001). Compared with no strangulation, multiple strangulation was associated with more IPV injury and risk factors for homicide, including loss of consciousness (ARR, 2.95; p < .05) and miscarriage (ARR, 5.08; p < .05). Women who had lost consciousness owing to strangulation were more likely to seek medical care than those who had been strangled but had not lost consciousness (p < .01).

CONCLUSIONS

Strangulation is a prevalent form of IPV that presents significant health risks to women. Women's health practitioners are optimally positioned to identify subtle signs and symptoms of strangulation, help women to understand the delayed sequelae and potential future fatality associated with strangulation, and connect them with appropriate resources to reduce the risk of morbidity and mortality.

Delayed-onset Reversible Cortical Blindness after Resuscitation from Cardiac Arrest

We present a patient who presented with cortical blindness (CB) 1 week after repeated cardiac arrest while undergoing treatment for an acute myocardial infarction. He had been revived within 5 min in each instance and was apparently neurologically normal until presentation. Magnetic resonance imaging showed subtle hyperintensities on fluid-attenuated inversion recovery and diffusion-weighted imaging in both temporooccipital cortices. A rapid recovery over the next 2 weeks was remarkable for the appearance of metamorphopsia. CB may present even days to weeks after hypoxic-ischemic encephalopathy following cardiac arrest, even in patients apparently without immediate neurological sequelae. The pathogenesis of this phenomenon remains to be fully elucidated, but is likely to be due to delayed effects of anoxia on the occipital cortex and may be analogous to the previously described syndrome of delayed posthypoxic leukoencephalopathy. Prognosis for visual recovery appears to be good.

Delayed posthypoxic leukoencephalopathy: a case series and review of the literature

BACKGROUND

Delayed posthypoxic leukoencephalopathy (DPHL) is a rare and underrecognized entity where patients manifest a neurological relapse after initial recovery from an acute hypoxic episode. We sought to describe the magnetic resonance imaging (MRI) findings in a group of patients with DPHL and review the available literature.

METHODS

Retrospective case series including patients who presented with neurological and/or psychiatric symptoms after recovery from an acute hypoxic episode. The history and clinical presentation were reviewed from the electronic medical records. MRI scans were evaluated from the picture archiving and communication system. We performed a comprehensive review of the English medical literature for prior published cases of DPHL and describe the key imaging findings that have been reported related to this condition.

RESULTS

A total of five patients were identified, including four patients with respiratory failure due to drug overdoses from benzodiazepines, opioids, and/or barbiturates, and one patient who presented after cardiopulmonary arrest due to pulmonary embolism. All patients showed diffuse, extensive, and confluent white matter signal abnormalities including prominent restricted diffusion, extending to the subcortical white matter and respecting the U-fibers. There was no gyral edema or contrast enhancement. In one case histopathology was available, which highlighted patchy subcortical myelin loss with sparing of U-fibers and demonstrated prominent macrophage/microglial inflammation with extensive axonal damage. Of the other four patients, two were at their neurological baselines and two had persistent neurological deficits at the time of discharge.

CONCLUSIONS

The described constellation of MRI findings is highly suggestive of DPHL in the appropriate clinical setting.

Toxic leukoencephalopathies

Leukoencephalopathy is a syndrome of neurologic deficits, including alteration of mental status, caused by pathologic changes in the cerebral white matter. The term, toxic leukoencephalopathy, encompasses a wide variety of exposures and clinical presentations. The diagnosis in these Frontiers in Clinical Neurotoxicology syndromes is made by careful attention to the history, clinical features, and radiologic findings. This article details three of the best-defined toxic leukoencephalopathies: delayed posthypoxic leukoencephalopathy, including delayed neurologic sequelae after carbon monoxide poisoning; heroin inhalation leukoencephalopathy; and posterior reversible encephalopathy syndrome.

Temporary recovery after resuscitation: delayed postanoxic encephalopathy

Delayed postanoxic encephalopathy is reported infrequently and is characterised by a lucid interval of seemingly good recovery from an anoxic insult. Days or even weeks may pass before changes in behaviour, motor responses or consciousness occur. Neurological deterioration may progress to coma, death or severe disability, whereas some patients have a second recovery period. Pathogenesis is yet to be discovered. Prognosis is reportedly poor, treatment is symptomatic and at best anecdotal. We present a case report and available literature.

CT and MR in non-neonatal hypoxic-ischemic encephalopathy: radiological findings with pathophysiological correlations

Non-neonatal hypoxic-ischemic encephalopathy is a clinical condition often related to cardiopulmonary arrest that demands critical management and treatment decisions. Management depends mainly on the degree of neurological impairment and prognostic considerations. Computed tomography (CT) is often used to exclude associated or mimicking pathology. If any, only nonspecific signs such as cerebral edema, sulci effacement, and decreased gray matter (GM)/white matter (WM) differentiation are evident. Pseudosubarachnoid hemorrhage, a GM/WM attenuation ratio <1.18, and inverted GM attenuation are associated with a poor prognosis. Magnetic resonance (MR) imaging is more sensitive than CT in assessing brain damage in hypoxic-ischemic encephalopathy. Some MR findings have similarities to those seen pathologically, based on spatial distribution and time scale, such as lesions distributed in watershed regions and selective injury to GM structures. In the acute phase, lesions are better depicted using diffusion-weighted imaging (DWI) because of the presence of cytotoxic edema, which, on T2-weighted images, only become apparent later in the early subacute phase. In the late subacute phase, postanoxic leukoencephalopathy and contrast enhancement could be observed. In the chronic phase, atrophic changes predominate over tissue signal changes. MR can be useful for estimating prognosis when other tests are inconclusive. Some findings, such as the extent of lesions on DWI and presence of a lactate peak and depleted N-acetyl aspartate peak on MR spectroscopy, seem to have prognostic value.

Post-hypoxic early selective putaminal necrosis followed by delayed extensive sub-cortical demyelination

OBJECTIVE

To describe the patterns of early and delayed hypoxic damage to the brain parenchyma.

METHODS

This paper reports a case with interesting clinical course and MRI brain changes in a patient following a single hypoxic-anoxic exposure after an alcoholic binge.

RESULTS

Bilaterally symmetrical putaminal necrosis was noted in the initial MRI, but subsequent follow-up revealed extensive demyelination of the sub-cortical white matter, associated with the clinical deterioration.

CONCLUSIONS

The brain, in general, and the neurons in caudate nucleus, putamen, globus pallidus and cerebral white matter, in particular, are susceptible to hypoxic injury. These changes may occur simultaneously and early or sequentially and late.

Delayed parkinsonism with a selective symmetric basal ganglia lesion after manual strangulation

A 21-year-old woman, who experienced manual strangulation, developed delayed parkinsonism associated with a selective symmetric basal ganglia lesion. The patient had recovered completely one year after early combination therapy. This case emphasizes the need for greater attention in detecting early brain injuries in those afflicted with strangulation so as to provide optimal management.

Forensic assessment of survived strangulation

By a retrospective analysis of all survived strangulation cases examined at the Institute of Forensic Medicine of Berne, Switzerland between 1987 and 2002, the authors tried to find out, if findings and symptoms of victims could be related to the fierceness of the assault and the mode of strangulation and if general evaluation criteria could be established on the basis of objective findings. One hundred and thirty-four survived strangulation cases were analysed on the basis of written reports, photographies and schematical sketches. Findings and symptoms reflected the fierceness of the assault in 71% of all cases by displaying a continuum of findings from minor injuries to severe traumatisation. This applied especially for cases of manual strangulation while other modes of strangulation resulted in different constellations of findings. As a result of this study, the authors deem the following classification of three degrees of severity as practical on condition that a complete forensic medical examination was performed upon the surviving victim shortly after the incident of strangulation: Light strangulation, confined to skin abrasions and/or reddening of the skin of the neck. Moderate strangulation, defined as bruising to, and/or bleeding from the neck, and/or damage to deeper soft tissues or the larynx, as exhibited by the symptoms of sore throat, difficulty in swallowing, and hoarseness. Severe, life-threatening strangulation if the victim presents petechial bleedings as a result of venous congestion with or without accompanying loss of consciousness.

Delayed postanoxic encephalopathy: a case report and literature review

Delayed postanoxic encephalopathy is a rare condition in which patients appear to make a complete clinical recovery after an episode of anoxia or hypoxia but then develop a relapse characterized by apathy, confusion, agitation, and/or progressive neurologic deficits. The incidence of delayed postanoxic encephalopathy is unclear but has been reported to range from less than 1 to 28 per 1000 in patients who have suffered hypoxic or anoxic events. The exact pathogenesis remains unknown. We describe a case of an independently living 51-year-old woman admitted to an inpatient rehabilitation unit 11 days after a respiratory arrest. At admission, she exhibited cognitive and visual deficits that were relatively mild but prevented a safe return to independent living. Two days later, she developed the sudden onset and rapid worsening of parkinsonian symptoms and excruciating bilateral lower-extremity pain. The pain was intractable, and over the next 2 days she progressed to being unable to walk or perform her activities of daily living without maximum assistance. A diagnosis of delayed postanoxic encephalopathy was made, and the patient responded to a trial of carbidopa and levodopa as well as redirection of her physical and occupational therapy programs. This case illustrates the unusual presentation of delayed postanoxic encephalopathy during inpatient rehabilitation and suggests that this condition should be considered if patients who have suffered an anoxic or hypoxic event show a sudden neurologic deterioration.

Survey results of women who have been strangled while in an abusive relationship

Few studies attempt to examine individual methods of domestic abuse. The objectives of this study are to evaluate strangulation as a method of domestic violence abuse: to determine the incidence of strangulation occurrence within the cycle of domestic violence, the subjective medical symptoms experienced by victims of intimate partner strangulation, and the elective utilization of health care following a strangulation incident. Sixty-two women were surveyed at two women's shelters in Dallas, Texas and Los Angeles, California and the Parkland Health & Hospital (PHHS) Violence Intervention Prevention (VIP) Center in Dallas, Texas. Each patient was individually interviewed and verbal responses were recorded. Statistics were performed using the SPSS program. Of the 62 surveyed, 42 (68%) had been strangled by their intimate partner who was a husband (23, 55%), boyfriend (13, 31%), or fiancé (2, 5%), by a mother, stranger, or friend (1 each). Strangulation, as a method of domestic violence, is quite common in women seeking medical help or shelter in a large urban city. This study suggests that strangulation occurs late in the abusive relationship; thus, women presenting with complaints consistent with strangulation probably represent women at higher risk for major morbidity or mortality.

Neuroimaging on delayed postanoxic encephalopathy with lesions localized in basal ganglia

A 59-year-old woman suffered from prolonged hypotension with myocardial infarction. Sixteen days after the episode, she showed bradykinesia, gait disturbance, and postural tremor. MRI revealed low signa intensities in the bilateral caudate nuclei and putamen on the T1-weighted image and high signal intensities on the T2-weighted image. PET with 18F-FDG revealed a severe decrease in glucose metabolism in bilateral basal ganglia. It is concluded that prolonged hypotension may induce localized delayed anoxic lesions in basal ganglia.

Strangulation injuries in children. Part 1. Clinical analysis

Over the past 4 years, 7.4% of deaths caused by strangulation in Peoria County, Ill., involved children under 18 years of age. Clinical review of a consecutive series of 13 children treated from 1985 through 1994 revealed an incidence of 32 of 10,000 intensive care unit admissions with a 5.5:1 male bias. Accidental causes were seen in six children, with suicide or autoerotic causes prevalent in older children and adolescents. Five children had behavioral disorders before injury. The initial Glasgow Coma Scale score was 8 or below in seven children. Cervical roentgenograms in all patients and computed tomographic examinations performed in seven children were interpreted as normal. Seven children required ventilatory assistance, and four had pneumonia or acute lung injury. Intracranial pressure monitoring in three children failed to reveal sustained elevations of pressure. Serial changes in electroencephalograms in five patients paralleled improvements in their clinical examinations. Ten children were normal on follow-up; one adolescent reported mild neurologic sequelae and one adolescent showed severe disability. One adolescent died 2 days after injury. Comparison of this series with previous reports of 26 children indicated that the extent of the initial injury and effectiveness of resuscitation were major determinates for outcome. Pulmonary complications were common, whereas the development of elevated intracranial pressure indicated a poor prognosis and suggested the use of telemetry in children, with clinical evidence of severe injury. Continued awareness of preventative measures for accidental strangulation in infants and intentional hanging in children with behavioral disorders may reduce the incidence of these injuries.

Selective sparing of human nucleus accumbens in aging and anoxia

OBJECTIVE

To investigate the effects of aging and anoxia on the nucleus accumbens.

METHODS

The number of neurons in nucleus accumbens and caudate nucleus in 35 patients over 65 and 35 under 65 years, all without neurological or psychiatric disease were counted.

RESULTS

There was no statistically significant difference between the number of neurons in the accumbens in the two groups, but there was a decrease in the number of neurons in the elderly group. There was no reduction in volume of the neuronal nucleoli of the accumbens measured in 12 elderly patients compared to controls. These data suggest a sparing of the accumbens from changes associated with aging. There was relative preservation of the nucleus accumbens in 3 patients with anoxic encephalopathy.

CONCLUSIONS

These results show that accumbens was resistant to both aging and anoxia, the mechanism of which is discussed.

Delayed post-anoxic encephalopathy

Delayed anoxic encephalopathy, a rare yet clinically and pathologically welldelineated complication of hypoxia with unknown pathogenesis, is described in a 40-year-old man following a drug overdose.

The neuropathogenesis of delirium. A need to focus our research

Delirium symptoms suggest dysfunction of multiple brain regions. However, little is known about delirium's underlying neuropathogenesis. This article addresses the need for research on neuroanatomic and neuropathophysiologic underpinnings of delirium, analogous to that of schizophrenia and affective disorders. Electrophysiologic tests, structural and functional brain imaging, and neurotransmitter studies in delirium are critically reviewed. The importance of both cerebral cortical and subcortical areas is noted, with emphasis on frontal, right-hemisphere, and subcortical regions, including caudate and anteromedial thalamus. Each symptom of delirium can be viewed from a neuroanatomic and neurochemical perspective. Recommendations for research are made throughout the article.

Delayed parkinsonism associated with hypotension in a child undergoing open-heart surgery

An eight-year-old boy developed acute parkinsonism four days after open-heart surgery for repair of a ventriculo-septal defect. During the procedure he experienced a hypotensive episode which required administration of positive-inotropic agents. Complementing the clinical signs of parkinsonism, CT scan showed symmetrical hypodensities in the basal ganglia, and decreased regional cerebral blood flow was demonstrated using 99mTc HMPAO SPECT. These findings were suggestive of a hypoxic-ischaemic insult to the basal ganglia. The child was treated with levodopa/carbidopa and subsequently completely recovered within a follow-up period of eight months. CT scan appearances and cerebral blood flow findings returned to normal. Parkinsonism secondary to a hypoxic-ischaemic insult to basal ganglia in children is a rare but reversible disorder, in contrast to its progressive course which results in severe disability in adults.

Thyroid storm in a young woman resulting in bilateral basal ganglia infarction

We describe a 30 year old woman who presented with thyroid storm. She had non-specific symptoms and few clinical signs of hyperthyroidism despite markedly raised thyroid hormone concentrations. Soon after admission her behaviour became abnormal and her level of consciousness deteriorated. Despite the rapid restoration of thyroid hormone concentrations to normal using conventional therapies, and correction of hypoxia resulting from acute pulmonary oedema, her level of consciousness did not improve. Cranial CT scanning revealed extensive bilateral basal ganglia infarction, a previously unreported complication of thyroid storm. This observation suggests that thyroid storm may predispose to hypoxic neurological damage.