Minor Deficits Research Articles

Regional issues in the global lead market

The world lead market will experience minor deficits in 2003 and 2004. These deficits alone are unlikely to reduce visible stocks of lead to the critically low levels necessary to provoke substantially higher prices. The world lead market is, however, undergoing structural change. Lead smelting has expanded rapidly in China and, in part due to a similar trend in zinc, is shifting away from the imperial smelting process (ISP). As a result, the production of refined lead in Western Europe is falling dramatically in 2003. Consumption patterns are also shifting. Consumption in the USA has been in decline since the collapse of the industrial battery sector in 2001, and there is growing evidence of a shift in battery manufacturing to China. Despite the generally neutral outlook for London Metal Exchange (LME) lead prices, these structural changes are causing disruption to the trade flows of lead, which is now impacting premiums and may impact LME prices. These issues are highly relevant to battery manufacturers.

False negative findings in intraoperative SEP monitoring: analysis of 658 consecutive neurosurgical cases and review of published reports

Objectives: To determine the sensitivity of intraoperative monitoring in neurosurgical operations using somatosensory evoked potentials and to identify reasons for false negative findings and possible settings with an increased risk...

Use of a Large Angioplasty Balloon for Predilation is a Risk Factor for Embolic Complications in Protected Carotid Stenting

Periprocedural neurological complications (PNCs) after carotid stenting were retrospectively analyzed to determine the risk factors with the use of various protective devices. Forty-three lesions in 40 patients were treated by carotid stenting with distal balloon protection for nearly all postdilation procedures and some predilation procedures. The following variables were statistically analyzed for association with PNCs: diameter of the angioplasty balloon used for predilation, use of a distal protection balloon during predilation, use of a protection balloon during postdilation, lesion-bifurcation distance, length of the lesion, age, clinical presentation of the lesion (symptomatic or asymptomatic), and hypercholesterolemia. PNCs occurred in five patients, four with minor deficits and one with major deficits. Univariate analysis showed large diameter of the predilation angioplasty balloon (p = 0.0026), use of a protection balloon during predilation (p = 0.0075), lesion length (p = 0.0003), and lesion-bifurcation distance (p = 0.0006) were significantly associated with PNCs. Multivariate analysis of these four variables showed that use of a large angioplasty balloon for predilation was the only independent predictor (p = 0.004, odds ratio 34.00) for the occurrence of PNCs. Use of a large angioplasty balloon for predilation carries the risk of periprocedural embolic complications. Therefore, even when a protection device is used, predilation should be performed with a small balloon.

Conditioned blood reperfusion markedly enhances neurologic recovery after prolonged cerebral ischemia

Objectives To determine whether controlled reperfusion using conditioned leukodepleted blood can substantially limit cerebral reperfusion injury following prolonged ischemia. Methods Eighteen pigs (25-35 kg) underwent 90 minutes of hypothermic circulatory arrest (19°C) to produce brain ischemia. At the start of rewarming, 10 pigs received uncontrolled reperfusion with unmodified (normal) blood. The other 8 pigs underwent 10 minutes of controlled reperfusion by selectively perfusing both common carotid arteries with blood passed through a CoBRA filter. This filter conditions the blood by removing white blood cells, platelets, and attenuating complement. Two other pigs underwent cooling and rewarming only (controls) without ischemia. Neurologic assessment was done using neurologic deficit scoring (0 = normal, 500 = brain death), and jugular venous samples were obtained for biochemical analysis postreperfusion. Results There were no statistical differences in hemodynamics between groups. At 6 hours postanesthesia, all animals receiving normal blood were substantially neurologically impaired. At 24 hours, they all had abnormal positioning and all but 1 were unable to sit or stand (neurologic score 124 ± 19). In contrast, nonischemic controls and pigs receiving conditioned blood reperfusion showed only minor neurologic deficits at 6 hours, and at 24 hours all were considered normal (neurologic scores 0 and 6 ± 5; P < .005 vs uncontrolled reperfusion). Compared with pigs receiving normal blood reperfusion, oxygen free radical formation (conjugated dienes 1.70 ± 0.03 vs 1.60 ± 0.02 Abs 240 nm; P < .05 vs uncontrolled reperfusion), and endothelin-1 release (2.12 ± 0.09 vs 1.84 ± 0.06 pg/mL; P < .05 vs uncontrolled reperfusion) were also significantly lower in animals receiving conditioned blood. Conclusions Following prolonged cerebral ischemia, reperfusion injury is avoided by delivering conditioned blood, which is devoid of white cells, platelets, and membrane attack complex. These results suggest that this modality is clinically useful in situations where the brain is subjected to prolonged ischemia.

Preserved functional competence of perilesional areas in drug-resistant epilepsy with lesion in supplementary motor cortex: fMRI and neuropsychological observations

We report a presurgical fMRI study and a longitudinal behavioral and structural MRI study in a 26-year-old right-handed woman with drug-resistant epilepsy of the supplementary motor region with cytoarchitectural dysplasia and minimal cortico-subcortical gliotic damage. fMRI scans were acquired during a silent phonemic verbal fluency task (VF), an automatic counting task (CT), and a finger-tapping motor task (MT). These were all compared with rest. Presurgical neuropsychological assessment was substantially normal with only a minor deficit in the domain of visuo-constructive and complex motor-planning skills. Noticeably, performance on phonemic verbal fluency was normal. Presurgical fMRI results revealed a normal specialization of left SMA and pre-SMA, including a fine-grained somatotopy for mouth and hand representations despite epilepsy. Immediately after surgical removal of the epileptogenic zone (the posterior third of the superior and middle frontal gyri including pre-SMA and part of SMA, and part of the anterior cingulate region—all of which were active presurgically at the fMRI tests), the patient suffered from transcortical motor aphasia temporarily. One year after surgery, she still showed impaired performance in the verbal fluency tasks while naming and comprehension were recovered. The patient was now free from seizures. This fMRI study supports the case that repeated seizures per se may not be sufficient to alter the distribution of neural representations of cognitive function. Selective behavioral impairment after surgical removal of brain areas that were activated during presurgical fMRI permits us to establish a causal link between these activations and task performance. This link could not have been made on the basis of activation patterns or lesion data taken on their own. These findings support the case that some epileptic patients may represent a unique opportunity for cognitive neuroscience studies.

Human immunodeficiency virus 1-associated minor motor disorders: perfusion-weighted MR imaging and H MR spectroscopy.

To investigate whether advanced magnetic resonance (MR) imaging techniques such as diffusion-weighted (DW) and perfusion-weighted (PW) MR imaging and hydrogen 1 (1H) MR spectroscopy can depict functional and pathophysiologic mechanisms in patients who have minor motor deficits (MMDs) associated with human immunodeficiency virus 1 (HIV-1). Thirty-two patients with results seropositive for HIV-1 and different degrees of HIV-1-related MMD underwent conventional brain MR imaging, as well as DW and PW MR imaging and 1H MR spectroscopy of the basal ganglia. PW MR imaging data were computed pixel by pixel for creation of time-to-peak, relative regional cerebral blood volume, and bolus amplitude parameter maps. In addition, quantitative regional cerebral blood flow (rCBF) maps were calculated with respect to the arterial input function by using the singular value decomposition algorithm. For 1H MR spectroscopy, a stimulated echo acquisition mode 20, or STEAM 20, sequence was used. Spectra were fit for determination of the signal intensities of the different metabolites. According to psychomotor testing results, patients were divided into three groups: group 1, 10 patients with normal motor function; group 2, eight patients with psychomotor slowing for the first time; and group 3, 14 patients who had had sustained pathologic psychomotor slowing for at least 6 months before the MR imaging examination. No patients had an abnormality at either conventional or DW MR imaging. PW MR imaging depicted significantly elevated rCBF in group 2 patients (P =.039, analysis of variance [ANOVA]) and significantly elevated myo-inositol-to-creatine ratio levels in group 3 patients (P =.020, ANOVA). Quantitative PW MR imaging and 1H MR spectroscopy can depict pathologic changes in patients who have HIV-1-related MMD but normal clinical examination and conventional MR imaging findings.

Long-term neurological outcome of childhood brain tumors treated by surgery only.

To evaluate the pattern of neurological late effects in patients who have received surgery only for a brain tumor in childhood and to identify possible risk factors for neurological sequelae. The medical, histologic, and operative records were reviewed for 65 consecutive patients operated for a benign brain tumor from 1970 to 1997, and all patients were re-examined after a median length of follow-up of 10.7 years. Thirty-four patients had posterior fossa tumors, 22 patients had cerebral hemisphere tumors, and nine patients had midline tumors. At the time of follow-up, 20 patients (31%) had no neurological deficits, 22 patients (34%) had minor deficits that did not interfere with their daily life activities, and 23 patients (35%) had moderate or severe deficits such as severe ataxia, spastic paresis, seriously reduced vision, or epilepsy with more than two seizures per year. Fourteen of the 31 patients (45%) registered with ataxia preoperatively had recovered fully. Six of seven patients had persistence of a pre- or postoperatively developed hemiparesis. Thirteen of 23 patients had persistence of cranial nerve deficits that developed second to surgery. Fifty-five percent of the 18 patients with seizures at diagnosis were seizure-free at follow-up. At follow-up both ataxia and hemiparesis were significantly more frequent among females (P =.02 and P =.03, respectively). In patients who received operation as the only treatment for their brain tumor, there was a good chance of total or partial recovery of preoperative and postoperative neurological deficits, although only one third of the patients will have no long-term neurological deficits.

Chemical ablation of sensory afferents in the walking system of the cat abolishes the capacity for functional recovery after peripheral nerve lesions.

Weakening the ankle extensor muscles of cats by denervation of the synergists of the medial gastrocnemius (MG) muscle results in transient increase in yield at the ankle during early stance. Recovery of ankle function occurs over a period of 1-2 weeks, is use-dependent, and is associated with increases in the strength of reflexes from MG group I muscle afferents and an increase in the magnitude of bursts in the MG muscles during stance. These observations have led to the hypothesis that feedback from large muscle afferents is necessary for functional recovery. In this investigation we have tested this hypothesis by examining functional recovery in animals treated with pyridoxine, a drug known to destroy large muscle afferents. In four adult animals we confirmed that pyridoxine abolished the group I-mediated tendon-tap reflex in the ankle extensor muscle, and subsequently found that group I afferents from MG were either destroyed or non-conducting. Immediately after pyridoxine treatment the animals showed severe locomotor dysfunction but all recovered significantly over a period of 1 or 2 months and showed only minor kinematics deficits at the time of the muscle denervations. In all four pyridoxine-treated animals, weakening of the ankle extensors by denervation of the synergists of the MG muscle resulted in a large increase in yield at the ankle that persisted almost unchanged for a month after the operation. The magnitude of burst activity in the MG muscle during early stance of the pyridoxine-treated animals either did not increase or increased only slightly after the denervation of synergists. These observations are consistent with the hypothesis that feedback from group I afferents is necessary for functional recovery in untreated animals.

Impact of perinatal asphyxia on the GABAergic and locomotor system

Perinatal asphyxia can cause neuronal loss and depletion of neurotransmitters within the striatum. The striatum plays an important role in motor control, sensorimotor integration and learning. In the present study we investigated whether perinatal asphyxia leads to motor deficits related to striatal damage, and in particular to the loss of GABAergic neurons. Perinatal asphyxia was induced in time-pregnant Wistar rats on the day of delivery by placing the uterus horns, containing the pups, in a 37 °C water bath for 20 min. Three motor performance tasks (open field, grip test and walking pattern) were performed at 3 and 6 weeks of age. Antibodies against calbindin and parvalbumin were used to stain GABAergic striatal projection neurons and interneurons, respectively. The motor tests revealed subtle effects of perinatal asphyxia, i.e. small decrease in motor activity. Analysis of the walking pattern revealed an increase in stride width at 6 weeks of age after perinatal asphyxia. Furthermore, a substantial loss of calbindin-immunoreactive (−22%) and parvalbumin-immunoreactive (−43%) cells was found in the striatum following perinatal asphyxia at two months of age. GABA A receptor autoradiography revealed no changes in GABA binding activity within the striatum, globus pallidus or substantia nigra. We conclude that perinatal asphyxia resulted in a loss of GABAergic projection neurons and interneurons in the striatum without alteration of GABA A receptor affinity. Despite a considerable loss of striatal neurons, only minor deficits in motor performance were found after perinatal asphyxia.

A Bi-centre Study of the Pattern and Evolution of readily detectable Neurological Sequelae of Acute Bacterial Meningitis

The pattern and evolution of obvious post-meningitic sequelae were determined in 187 post-neonatal children followed up at two tertiary centres. The pattern of sequelae was classified using previously described schemes, as well as by the number of deficits per child. One hundred and eighty-seven children were assessed on discharge, 157 after six weeks of discharge and 134 after three months. The incidence of sequelae was 40/187 (21.4 percent) on discharge versus 23/157 (14.7 percent) after six weeks (p = 0.106) and 18/134 (13.4 percent) after three months (p = 0.069) of follow up. Two (1.4 percent) of the 147 children who were apparently normal on discharge had sequelae on follow up, while two (7.4 percent) of the 27 children discharged with major sequelae, died. Among 17 children who were followed up for at least six months, three (18 percent) at >6 wks to 6 months (p = 0.034) had persistent deficits. Among the 42 children with sequelae, 29 (69 percent) had major deficits alone (n = 15) or with minor deficits (n = 14). Fifteen (36 percent) had one, 14 (33 percent) two and 13 (31 percent) >3 deficits. There was full or partial resolution of deficits in 15/19 (79 percent) children with sequelae who were treated with and in 6/15 (40 percent) (p

Craniocervical Tuberculosis: Protocol of Surgical Management

OBJECTIVE Craniovertebral junction tuberculosis (CVJ-TB) is rare and occurs in only 0.3 to 1% of patients with tuberculous spondylitis. In the available literature, the treatment options offered for this entity have ranged from a purely conservative approach to radical surgery without well-defined guidelines. In this study, we attempt to establish the most effective strategy for the management of this condition. METHODS Twenty-five patients with CVJ-TB were treated during the past 8 years. Severe neck pain, restricted neck movement, and myelopathy were the predominant symptoms. The patients were graded according to their disability as follows: Grade I (n = 7), only neck pain with no pyramidal tract involvement; Grade II (n = 8), independent with minor disability; Grade III (n = 1), partially dependent on others for assistance with activities of daily living; and Grade IV (n = 9), completely dependent on others for assistance with all activities of daily living. Nine patients in Grade IV also had severe respiratory compromise. In all patients, lateral radiographs of the CVJ in flexion and extension were used to determine the presence of atlantoaxial dislocation (AAD). Bony destruction, paraspinal abscess, and thecal compression were seen on intrathecal contrast computed tomographic scans (n = 9) and magnetic resonance imaging studies (n = 22). Under the cover of antituberculous therapy (ATT) administered for 18 months, the patients were placed under a management protocol that took into account the patient’s preoperative grade, the presence of mobile or fixed AAD, bony destruction and retropharyngeal abscess formation at the CVJ, and the clinicoradiological response to ATT within 3 months. Thus, 14 patients were kept on conservative management, with their neck movements stabilized with an external orthosis; 4 patients underwent a single-stage transoral decompression and posterior fusion procedure; and 7 patients underwent direct posterior fusion. RESULTS In a follow-up period that ranged from 6 months to 7 years (mean, 2.5 yr), the patients in Grades I and II maintained their neurological status. The single patient in Grade III improved to Grade II. Seven of the nine patients in Grade IV returned to normal, and one improved to Grade II. Neck pain improved in all patients. The only death in the series occurred as a result of aspiration pneumonitis leading to septicemia in a child in Grade IV with poor respiratory status and multilevel tuberculous involvement who had undergone transoral decompression and posterior fusion for fixed AAD. CONCLUSION This study discusses the clinicoradiological presentation as well as the management of CVJ-TB, in which ATT is administered for 18 months. In the patients with minor deficits (Grades I and II), conservative neck stabilization is adopted; in the patients with severe deficits (Grades III and IV) due to significant cervicomedullary compression caused by fixed AAD or bone destruction and granulation, anterior decompression and posterior fusion are performed. Patients with persistent reducible AAD undergo direct posterior fusion. A significant improvement is possible even in poor-grade patients with judicious use of the surgical options and ATT.

A new miniature fiber oxygenator for small animal cardiopulmonary bypass.

Neurocognitive decline following cardiac surgery is an increasing problem, particularly affecting older patients. The use of cardiopulmonary bypass is a suspected cause. Research into pathophysiology and possible preventive measures requires the use of an animal model. Commercial oxygenators are too large and expensive for use in small animals. We describe a fiber oxygenator scaled for use in the rat. In vitro and in vivo testing show that it is able to support full gas exchange in this size of animal, and causes no allergic or toxic reactions.

Neurotoxic complications of chemotherapy in patients with cancer: clinical signs and optimal management.

Neurotoxic side effects of chemotherapy occur frequently and are often a reason to limit the dose of chemotherapy. Since bone marrow toxicity, as the major limiting factor in most chemotherapeutic regimens, can be overcome with growth factors or bone marrow transplantation, the use of higher doses of chemotherapy is possible, which increases the risk of neurotoxicity. Chemotherapy may cause both peripheral neurotoxicity, consisting mainly of a peripheral neuropathy, and central neurotoxicity, ranging from minor cognitive deficits to encephalopathy with dementia or even coma. In this article we describe the neurological adverse effects of the most commonly used chemotherapeutic agents. The vinca-alkaloids, cisplatin and the taxanes are amongst the most important drugs inducing peripheral neurotoxicity. These drugs are widely used for various malignancies such as ovarian and breast cancer, and haematological cancers. Chemotherapy-induced neuropathy is clearly related to cumulative dose or dose-intensities. Patients who already have neuropathic symptoms due to diabetes mellitus, hereditary neuropathies or earlier treatment with neurotoxic chemotherapy are thought to be more vulnerable for the development of chemotherapy-induced peripheral neuropathy. Methotrexate, cytarabine (cytosine arabinoside) and ifosfamide are primarily known for their central neurotoxic side effects. Central neurotoxicity ranges from acute toxicity such as aseptic meningitis, to delayed toxicities comprising cognitive deficits, hemiparesis, aphasia and progressive dementia. Risk factors are high doses, frequent administration and radiotherapy preceding methotrexate chemotherapy, which appears to be more neurotoxic than methotrexate as single modality. Data on management and neuroprotective agents are discussed. Management mainly consists of cumulative dose-reduction or lower dose-intensities, especially in patients who are at higher risk to develop neurotoxic side effects. None of the neuroprotective agents described in this article can be recommended for standard use in daily practise at this moment, and further studies are needed to confirm some of the beneficial effects described.

Follow-up into young adulthood after cardiopulmonary resuscitation in term and near-term newborn infants. II. Neuropsychological consequences.

Brain injury after neonatal cardiopulmonary resuscitation in the term baby is often described as an all-or-nothing phenomenon, but little is known about possible late cognitive consequences. The aim of this study was therefore to investigate whether children who needed cardiopulmonary resuscitation because of presumed mild and moderate intra-partum asphyxia with no evidence of neurological impairments at 18 mo of age may display neuropsychological impairments later in life. A long-term follow-up of young adults was carried out. A blinded comprehensive neuropsychological assessment of the main aspects of cognitive functions was made. The subjects who were resuscitated were divided into two groups according to the clinical course: 20 cases with mild asphyxia and 11 cases with moderate asphyxia, all followed prospectively and compared with 18 healthy controls. The 31 subjects were born at term or near-term and selected randomly from 59 infants born in 1969-1978 at Sahlgren's Hospital, Göteborg. All infants with early neurological impairments were excluded. No major differences could be established between the two clinical groups and normal controls in any aspects of cognitive function or intelligence. All the groups performed within the normal range in all tests. A tendency toward minor deficits in verbal ability in the mild group compared to the controls was found. Only one subject had a clear, defined memory deficit. Infants who underwent cardiopulmonary resuscitatation at birth without neurological deficits at 18 mo of age did not show any cognitive deficits or neuropsychological impairments in adulthood even though inferior performance on some verbal subtests was observed compared to the control group.

Follow‐up into young adulthood after cardiopulmonary resuscitation in term and near‐term newborn infants. II. Neuropsychological consequences

Aim: Brain injury after neonatal cardiopulmonary resuscitation in the term baby is often described as an all‐or‐nothing phenomenon, but little is known about possible late cognitive consequences. The aim of this study was therefore to investigate whether children who needed cardiopulmonary resuscitation because of presumed mild and moderate intra‐partum asphyxia with no evidence of neurological impairments at 18 mo of age may display neuropsychological impairments later in life. Methods: A long‐term follow‐up of young adults was carried out. A blinded comprehensive neuropsychological assessment of the main aspects of cognitive functions was made. The subjects who were resuscitated were divided into two groups according to the clinical course: 20 cases with mild asphyxia and 11 cases with moderate asphyxia, all followed prospectively and compared with 18 healthy controls. The 31 subjects were born at term or near‐term and selected randomly from 59 infants born in 1969–1978 at Sahlgren's Hospital, Göteborg. All infants with early neurological impairments were excluded. Results: No major differences could be established between the two clinical groups and normal controls in any aspects of cognitive function or intelligence. All the groups performed within the normal range in all tests. A tendency toward minor deficits in verbal ability in the mild group compared to the controls was found. Only one subject had a clear, defined memory deficit. Conclusions: Infants who underwent cardiopulmonary resuscitatation at birth without neurological deficits at 18 mo of age did not show any cognitive deficits or neuropsychological impairments in adulthood even though inferior performance on some verbal subtests was observed compared to the control group.

Neuronavigation and Functional MRI for Surgery in Patients with Lesion in Eloquent Brain Areas

Surgery in patients with lesions in eloquent areas is still a challenge for the neurosurgeon. The aim of surgical interventions should be the radical removal of the lesions with functional preservation. Functional brain imaging methods provide the preoperative demonstration of those brain areas and their relationship to pathologic structures. Twenty-seven patients with pathologic lesions in or near eloquent regions were investigated with functional magnetic resonance imaging (fMRI). Nineteen patients were neurologically intact preoperatively, and presented only with headache and/or seizure. Eight patients had a minor neurological deficit. Twenty-five patients underwent surgery. Preoperatively a computed tomography (CT) scan or a magnetic resonance imaging procedure with five skin fiducials was performed. The data were transferred to the neuronavigation workstation. The tumour was lined out in colours, and reconstruction in a triplanar format as well as three-dimensionally was implemented. The information from the fMRI concerning the functional areas was transferred into the images manually to account for EPI distortions. Fifteen patients were operated on using the combination fMRI/neuronavigation. Diagnoses included eleven gliomas, two meningeomas, one metastasis and one cavernoma. In seven patients the tumour was removed completely, eight patients had residual tumour, demonstrated by early postoperative MRI. All patients with residual tumour had gliomas that involved functional areas. Postoperatively no patient had an additional neurological deficit. Functional MRI provides important additional information in patients with lesions in eloquent brain areas. In combination with neuronavigation this is a very helpful technique for surgical interventions on these patients to reduce morbidity. Nonetheless, there are still open questions concerning accuracy of display of the functional areas and integration into a neuronavigation system.

Two distinct forms of minor neurological dysfunction: perspectives emerging from a review of data of the Groningen Perinatal Project

Two distinct forms of minor neurological dysfunction: perspectives emerging from a review of data of the Groningen Perinatal Project

Effects of underwater sound exposure on neurological function and brain histology

To evaluate the safety of sonar exposure from a neurological perspective, the vulnerability of the central nervous system to underwater exposure with high-intensity, low-frequency sound (HI-LFS) was experimentally examined. Physiological, behavioral and histological parameters were measured in anesthetized, ventilated rats exposed to brief (5 min), underwater HI-LFS. Exposure to 180 dB sound pressure level (SPL) re 1 μPa at 150 Hz ( n = 9) did not alter acute cardiovascular physiology (arterial blood pH, pO 2, pCO 2, heart rate, or mean arterial blood pressure) from that found in controls ( n = 11). Rats exposed to either 180 dB SPL re 1 μPa at 150 Hz ( n = 12) or 194 dB SPL re 1 μPa at 250 Hz ( n = 12) exhibited normal cognitive function at 8 and 9 days after sound exposure. Evaluation of neurological motor function revealed a minor deficit 7 days after 180 dB SPL/150 Hz exposure that resolved by 14 days, and no deficits after 194 dB SPL/250 Hz exposure. No overt histological damage was detected in any group. These data suggest that underwater HI-LFS exposure may cause transient, mild motor dysfunction.

Symptomatic vasospasm after subarachnoid haemorrhage: assessment of brain damage by diffusion and perfusion-weighted MRI and single-photon emission computed tomography.

Our purpose was to assess the usefulness of diffusion- and perfusion-weighted MRI for the detection of ischaemic brain damage in patients with suspected vasospasm after subarachnoid haemorrhage (SAH). We studied 11 patients admitted with a ruptured aneurysm of the anterior circulation and suspected of intracranial vasospasm on clinical examination and transcranial Doppler sonography (TCD). All were investigated by technetium-hexamethyl-propylene amine oxime (Tc-HMPAO) single photon emission computed tomography (SPECT) and diffusion and perfusion-weighted MRI (DWI, PWI) within 2 weeks of their SAH. Trace images and TTP maps were interpreted by two examiners and compared with clinical and imaging follow-up. PWI revealed an area of slowed flow in seven patients, including four with major and three with minor hypoperfusion on SPECT. In two patients, PWI did not demonstrate any abnormality, while SPECT revealed major hypoperfusion in one and a minor deficit hypoperfusion in the other. Two patients with high signal on DWI had a permanent neurological deficit.

Isolated extradural hematoma in children presenting to an emergency department in Australia.

Isolated extradural hematoma (EDH) is becoming more frequently recognized in emergency departments (EDs) in children. We describe the natural history of children with isolated EDH presenting to a large Children's Hospital ED. This is a descriptive case series study using a retrospective review of the medical records of children presenting to the ED with a diagnosis of isolated EDH over 8 years. Comparison was made with children having other injuries in addition to EDH. The cause, nature of injury, presentations to hospital, management, outcome, and any association with nonaccidental injuries (NAI) were analyzed. Of the 35 cases with a final diagnosis of isolated EDH initially presenting to the ED, 70% were over 3 years of age (mean 6.6 years), and 60% were boys. A fall of less than half a meter was the cause of isolated EDH in 51.4% of patients. The remaining cases resulted from a fall from a height greater than half a meter (17.1%), a motor vehicle accident (11.4%), being hit by an object (8.6%), a bicycle accident (5.7%), and a skateboard accident (5.7%). Children younger than 3 years presented within 24 hours of injury in 70% of cases, compared with 65% of older children. In 95% of cases, presentation was nonspecific, suggesting a medical rather than a surgical problem. This resulted in a delay in seeking emergency care and a delay in final diagnosis for these patients. Surgical drainage was required in 68.6% of cases, with older children being more likely to be managed conservatively. In 23.4% of cases, minor residual neurologic deficit occurred; there were no cases of serious long-term problems. There were no cases of NAI in the children studied. This report highlights falls as a common cause of isolated EDH in children. Delay in presentation for clinical assessment is common, because many children have nonspecific presentation that is suggestive of a medical problem. No cases of NAI were reported in this study.