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H P Haring

Publications and source records attributed to H P Haring.

At least 19 recordsLinked to original sources
PubMed2002

Rehabilitation approaches to stroke.

This article describes the state of the science in stroke rehabilitation dealing with three main topics: (1) General approach to stroke rehabilitation (stroke services and stroke units), (2) Neurophysiological and pharmacological interventions (facilitation of brain repair mechanisms) and (3) Experimental approaches (neuronal transplantation). Stroke rehabilitation is an active process beginning during acute hospitalisation, progressing to a systematic program of rehabilitation services and continuing after the individual returns to the community. There is world-wide consensus that stroke patients should be treated at specialised stroke unit with specially trained medical and nursing staff, co-ordinated multidisciplinary rehabilitation and education programs for patients and their families. Stroke Unit has been shown to be associated with a long-term reduction of death and of the combined poor outcomes of death and dependency, independent of patients age, sex, or variations in stroke unit organisations. No study has clearly shown to what extent the beneficial effect is due to specific rehabilitation strategies. New imaging studies in stroke patients indicate altered post stroke activation patterns, which suggest some functional reorganisation. Reorganisation may be the principle process responsible for recovery after stroke. It is assumed that different post ischaemic interventions like physiotherapy, occupational therapy, speech therapy, electrical stimulation, etc. facilitates such changes. Scientific evidence demonstrating the values of specific rehabilitation interventions after stroke is limited. Comparisons between different methods in current use have so far mostly failed to show that any particular physiotherapy, occupational therapy, speech therapy or stroke rehabilitation strategy is superior to another. Clinical data are strongly in favour of early mobilisation and training. Pharmacological interventions in animals revealed that norepinephrine, amphetamine and other alpha-adrenergic stimulating drugs can enhance motor performance after unilateral ablation of the sensory motor cortex. The clinical data in humans are rather contradictory. Neural grafting and neurogenesis are new potential modes of stroke therapy. Neural grafting enhanced functional outcome and reduced thalamic atrophy in rats only when combined with housing in enriched environments. Recent studies have shown that stem cells can differentiate to neurons in the adult human dentate gyrus in vivo.

Activities of Daily Living↗
PubMed2001

Rapid loss of microvascular integrin expression during focal brain ischemia reflects neuron injury.

The integrity of cerebral microvessels requires the close apposition of the endothelium to the astrocyte endfeet. Integrins alpha1beta1 and alpha6beta4 are cellular matrix receptors that may contribute to cerebral microvascular integrity. It has been hypothesized that focal ischemia alters integrin expression in a characteristic time-dependent manner consistent with neuron injury. The effects of middle cerebral artery occlusion (MCAO) and various periods of reperfusion on microvasclar integrin alpha1beta1 and alpha6beta4 expression were examined in the basal ganglia of 17 primates. Integrin subunits alpha1 and beta1 colocalized with the endothelial cell antigen CD31 in nonischemic microvessels and with glial fibrillary acidic protein on astrocyte fibers. Rapid, simultaneous, and significant disappearance of both integrin alpha1 and beta1 subunits and integrin alpha6beta4 occurred by 2 hours MCAO, which was greatest in the region of neuron injury (ischemic core, Ic), and progressively less in the peripheral (Ip) and nonischemic regions (N). Transcription of subunit beta1 mRNA on microvessels increased significantly in the Ic/Ip border and in multiple circular subregions within Ic. Microvascular integrin alpha1beta1 and integrin alpha6beta4 expression are rapidly and coordinately lost in Ic after MCAO. With loss of integrin alpha1beta1, multiple regions of microvascular beta1 mRNA up-regulation within Ic suggest that microvessel responses to focal ischemia are dynamic, and that multiple cores, not a single core, are generated. These changes imply that microvascular integrity is modified in a heterogeneous, but ordered pattern.

Animals↗
PubMed1999

Attenuated corticomedullary contrast: An early cerebral computed tomography sign indicating malignant middle cerebral artery infarction. A case-control study.

BACKGROUND AND PURPOSE: No neuroradiological markers have been characterized that support a timely decision for decompressive surgery in malignant middle cerebral artery (MCA) infarction (mMCAI). This case-control study was designed to analyze whether early cerebral CT (CCT) scanning provides reliable information for the prospective selection of stroke patients at risk of developing mMCAI. METHODS: Thirty-one pairs (n=62) were formed with cases (mMCAI) and controls (acute but not malignant MCA infarction) closely matched in terms of age, sex, and stroke etiology. CCT was performed within 18 hours of stroke onset and analyzed by a blinded neuroradiologist according to a defined panel of 12 CCT criteria. RESULTS: In terms of predicting mMCAI, the criteria of extended MCA territory hypodensities >67% and >50%, hemispheric brain swelling, midline shift, and hyperdense MCA sign exhibited high specificity (100%, 93. 5%, 100%, 96.7%, and 83.9%, respectively) but low sensitivity (45.2%, 58.1%, 12.9%, 19.4%, and 70.9%, respectively). Two criteria yielded high sensitivity (subarachnoid space compressed, 100%; cella media compressed, 80.6%) but low specificity (29% and 74.2%, respectively). The criterion of attenuated corticomedullary contrast yielded both high specificity (96.8%) and sensitivity (87.1%). The latter remained as the crucial criterion [Exp(B)=90.8; 95% CI, 5.8 to 1427. 5] in a 2-tailed logistic regression analysis with the strongest correlating parameters (Spearman correlation factor >/=0.6 or </=-0.6). CONCLUSIONS: The analysis of CCT scans within 18 hours of stroke onset revealed an attenuated corticomedullary contrast as the crucial CCT criterion, which, with both sufficient sensitivity and specificity, predicted mMCAI with 95% certainty.

Adult↗
PubMed1998

Prediction of recovery from post-traumatic vegetative state with cerebral magnetic-resonance imaging.

BACKGROUND: The early post-traumatic vegetative state (VS) is compatible with recovery. Various clinical and laboratory tests have failed to predict recovery so we assessed the value of cerebral magnetic-resonance imaging (MRI) in prediction of recovery. METHODS: 80 adult patients in post-traumatic VS had cerebral MRI between 6 weeks and 8 weeks after injury. MRIs were reviewed by three neuroradiologists for the number, sizes, and location of brain lesions. Three neurologists assessed the patients at the time of MRI and at 2 months, 3 months, 6 months, 9 months, and 12 months after injury using the Glasgow Outcome Scale. FINDINGS: At 12 months, 38 patients had recovered while 42 patients remained in the VS. The demographic characteristics and causes and severity of injury were similar in patients in persistent VS (PVS) and those who recovered (NPVS). An average of 6.1 different brain areas were injured in patients in PVS compared with 4.6 areas in patients who had NPVS. Patients in PVS revealed a significantly higher frequency of corpus callosum, corona radiata, and dorsolateral brainstem injuries than did patients who recovered. Logistic regression analysis showed that corpus callosum and dorsolateral brainstem injuries were predictive of non-recovery. The adjusted odds ratios for non-recovery of patients with a corpus callosum lesion and dorsolateral brainstem injury were 213.8 (95% CI 14.2-3213.3), and 6.9 (11-42.9), respectively. In contrast, clinical characteristics, such as initial score on the Glasgow Coma Scale, age, and pupillary abnormalities failed to predict recovery. INTERPRETATION: Cerebral MRI findings in the subacute stage after head injury can predict the outcome of the post-traumatic VS. Corpus callosum and dorsolateral brainstem lesions are highly significant in predicting non-recovery.

Adult↗
PubMed1998

The persistent vegetative state after closed head injury: clinical and magnetic resonance imaging findings in 42 patients.

OBJECT: In this retrospective study, the authors analyzed the frequency, anatomical distribution, and appearance of traumatic brain lesions in 42 patients in a posttraumatic persistent vegetative state. METHODS: Cerebral magnetic resonance (MR) imaging was used to detect the number of lesions, which ranged from as few as five to as many as 19, with a mean of 11 lesions. In all 42 cases there was evidence on MR imaging of diffuse axonal injury, and injury to the corpus callosum was detected in all patients. The second most common area of diffuse axonal injury involved the dorsolateral aspect of the rostral brainstem (74% of patients). In addition, 65% of these patients exhibited white matter injury in the corona radiata and the frontal and temporal lobes. Lesions to the basal ganglia or thalamus were seen in 52% and 40% of patients, respectively. Magnetic resonance imaging showed some evidence of cortical contusion in 48% of patients in this study; the frontal and temporal lobes were most frequently involved. Injury to the parahippocampal gyrus was detected in 45% of patients; in this subgroup there was an 80% incidence of contralateral peduncular lesions in the midbrain. The most common pattern of injury (74% in this series) was the combination of focal lesions of the corpus callosum and the dorsolateral brainstem. In patients with no evidence of diffuse axonal injury in the upper brainstem (26% in this series), callosal lesions were most often associated with basal ganglia lesions. Lesions of the corona radiata and lobar white matter were equally distributed in patients with or without dorsolateral brainstem injury. Moreover, cortical contusions and thalamic, parahippocampal, and cerebral peduncular lesions were also similarly distributed in both groups. CONCLUSIONS: The data indicate that diffuse axonal injury may be the major form of primary brain damage in the posttraumatic persistent vegetative state. In addition, the authors demonstrated in this study that MR imaging, in conjunction with a precise clinical correlation, may provide useful supportive information for the accurate diagnosis of a persistent vegetative state after traumatic brain injury.

Adolescent↗
PubMed1997

Cerebrospinal fluid (CSF) pharmacokinetics of intraventricular vancomycin in patients with staphylococcal ventriculitis associated with external CSF drainage.

We studied the efficacy and pharmacokinetics of intraventricularly administered vancomycin in three patients with shunt-associated staphylococcal ventriculitis. We instilled 10 mg of the drug intraventricularly every 24 hours. Cerebrospinal fluid (CSF) levels were measured 1 hour after instillation and then every 2 hours. Peak vancomycin levels reached a mean of 292.9 microg/mL. The mean trough levels, measured immediately before readministration of vancomycin, were 7.6 microg/mL; this level has proved to be sufficient for maintaining the necessary steady-state serum concentration of vancomycin. All three patients were cured clinically and bacteriologically, and CSF parameters returned to normal within 5-13 days. No side effects were observed. Our results suggest that intraventricularly administered vancomycin is a valuable therapeutic strategy for treating shunt-associated staphylococcal ventriculitis. In addition, we provide evidence that 10 mg of vancomycin, administered intraventricularly every 24 hours, allows maintenance of therapeutic drug levels in the CSF for at least 24 hours.

Brain Injuries↗
PubMed1997

Impaired microcirculation and tissue oxygenation in human cerebral malaria: a single photon emission computed tomography and near-infrared spectroscopy study.

Serial single photon emission computed tomography (SPECT), near-infrared spectroscopy (NIRS), and transcranial doppler (TCD) sonography examinations were performed to investigate changes of cerebral perfusion and tissue oxygenation in a patient with complicated cerebral malaria that have been acquired in Nigeria. On admission to the Neurologic Intensive Care Unit in Innsbruck, Austria, SPECT and NIRS revealed focal right hemispheric hypoperfusion and decreased oxygen saturation, respectively, correlating exactly to the patient's right hemispheric localizing signs. In contrast, TCD examinations of the basal cerebral vessels revealed normal flow patterns. The patient showed an initial Plasmodium falciparum parasitemia rate of 30% and was cured by intravenous quinine and oral mefloquine therapy. He was discharged without neurologic symptoms. Follow-up SPECT and NIRS examinations revealed regular cerebral perfusion and oxygenation patterns in both cortical hemispheres. In summary, the presented findings provide first evidence that noninvasive SPECT and NIRS may be important diagnostic tools in the evaluation of impaired cerebral microcirculation in patients with P. falciparum malaria.

Adult↗
PubMed1996

E-selectin appears in nonischemic tissue during experimental focal cerebral ischemia.

BACKGROUND AND PURPOSE: E-selectin participates in leukocyte-endothelial adhesion and the inflammatory processes that follow focal cerebral ischemia and reperfusion. The temporal and topographical patterns of microvascular E-selectin presentation after experimental focal cerebral ischemia are relevant to microvascular reactivity to ischemia. METHODS: The upregulation and fate of E-selectin antigen during 2 hours of middle cerebral artery occlusion (n = 4) and 3 hours of occlusion with reperfusion (1 hour, n = 4; 4 hours, n = 6; 24 hours, n = 6) were evaluated in the nonhuman primate. E-selectin and E:P-selectin immunoreactivities were semiquantitated with the use of computerized light microscopy video imaging and laser confocal microscopy. RESULTS: Three patterns of microvascular E-selectin expression, defined by the antibody E-1E4, were confirmed by complete elimination of E-1E4 binding after incubation with soluble recombinant human E-selectin: (1) Low immunoperoxidase intensity was observed in ischemic microvessels at 2 hours of occlusion extending to 4 hours of reperfusion (E-selectin/laminin = 0.32 +/- 0.10). (2) A significant fraction of ischemic microvessels displayed high-intensity E-selectin signal by 24 hours of reperfusion (0.61 +/- 0.17) compared with control and nonischemic tissues (2P < .003). (3) In the contralateral nonischemic basal ganglia and other nonischemic tissues, low but significant E-selectin levels appeared by 24 hours of reperfusion (2P = .0005). The latter were further confirmed by an E:P-selectin immunoprobe. CONCLUSIONS: E-selectin antigen is distinctively and significantly upregulated in nonhuman primate brain after focal ischemia and reperfusion. The late appearance of E-selectin in nonischemic cerebral tissues suggests stimulation by transferable factors generated during brain injury.

Animals↗
PubMed1995

Hyperventilation reverses the nitrous oxide-induced increase in cerebral blood flow velocity in human volunteers.

Because hypocapnia is routine during general anaesthesia for intracranial procedures, we have compared, in 13 healthy volunteers, the effect of normocapnia (PE'CO2 5.3 kPa) and hypocapnia (PE'CO2 3.3 kPa) on mean blood flow velocity in the middle cerebral artery (Vmca) during normoventilation and hyperventilation with air and with 50% nitrous oxide in oxygen. After replacement of air with 50% nitrous oxide in oxygen, there was an increase in mean Vmca during normoventilation (air: mean 68.23 (SD 16.98) cm s-1 vs nitrous oxide in oxygen: 90.69 (20.41) cm s-1; P < 0.01), whereas during hyperventilation mean Vmca values were similar regardless of the inhaled gas mixture (air: 43.46 (9.97) cm s-1 vs nitrous oxide in oxygen: 41.69 (8.08) cm s-1. Our data suggest that the nitrous oxide-induced increase in mean Vmca can be blocked by hyperventilation.

Adult↗
PubMed1994

Continuous positive airway pressure breathing increases cerebral blood flow velocity in humans.

The effect of a continuous positive airway pressure (CPAP) of 12 cm H2O on mean middle cerebral artery flow velocity (CBFV) was studied in nine human volunteers by means of transcranial Doppler sonography (TCD). During CPAP breathing, CBFV increased (45 +/- 9 vs 59 +/- 11 cm/s; P < 0.001; mean +/- SD), and pulsatility index (PI) decreased (0.87 +/- 0.1 vs 0.74 +/- 0.2; P < 0.05), indicating an increase in cerebral blood flow due to cerebral vasodilation. This phenomenon should be taken into account when CPAP is applied to patients with intracranial disease or when assessing CBFV patterns of patients during CPAP respiration.

Adult↗
PubMed1993

Time course of cerebral blood flow velocity in central nervous system infections. A transcranial Doppler sonography study.

In a 3-year period, 110 patients with central nervous system infections of various causes were examined serially by means of transcranial Doppler sonography. In viral-induced infections, no changes of flow velocity in basal cerebral arteries were seen, whereas in bacterial meningitis, a significant increase of blood flow velocity in the middle cerebral artery was recorded. Its extent was mainly associated with the type of the infectious agent, most frequently observed in pneumococcal meningitis (77%). The increase was up to 100% of the baseline values and was reversible in all cases. All patients were offered full-scale neurointensive care, and all subjects with bacterial meningitis were fully heparinized.

Adolescent↗
PubMed1993

Isolated pontine lesion in algid cerebral malaria: clinical features, management, and magnetic resonance imaging findings.

Malaria, the most important of all tropical diseases, causes approximately one million deaths per year. In Plasmodium falciparum malaria, the organs most affected are the brain, kidneys, lungs, and liver. Cerebral involvement is the most important lethal complication with a mortality rate of up to 50%. We report a patient with malignant, tertian falciparum malaria with an initial parasitemia rate of 60% and severe cerebral, hepatorenal, and pulmonary involvement. In addition to the severe diffuse encephalopathy, an initial neurologic examination showed signs of a pontine lesion that was confirmed by cerebral magnetic resonance imaging. We therefore conclude that cerebral malaria may be responsible for focal neurologic lesions that can be demonstrated by this procedure.

Adult↗
PubMed1993

[Course and management of tetanus].

Within a span of 18 months 4 patients (2 men, 2 women) were admitted with generalized tetanus to our neurological intensive care unit. The "period of onset" ranged from 2 to 14 days. All patients needed artificial ventilation over 17 to 38 days. The clinical course was complicated by gram-negative pneumonia in 3 of the 4 patients. Time of hospitalization ranged between 35 and 60 days. One patient had never been immunized against tetanus. The other 3 had not received a booster dose for over 10 years. All 4 patients survived, 3 of them without sequelae.

Adult↗
PubMed1992

Hemodynamic findings in migraine patients on transcranial Doppler sonography.

Forty migraine patients were examined by means of 3D-transcranial Doppler scanning (TCD). The complete circle of Willis was investigated in all patients during headache-free intervals. TCD investigations were repeated in 10 patients during a migraine attack, in one patient twice. Based on the diagnostic criteria of the "headache classification committee of the international headache society" 23 patients were assigned to a "migraine without aura" group and 17 to a "migraine with aura" group. Twenty age-matched volunteers, not suffering from headache or any vascular disease, served as a control group. No significant differences were detected between the hemodynamic data of the control group and the migraine groups both with respect to the headache-free interval and the attack. No hemodynamic changes in keeping with the pathophysiologic hypothesis of vasospasm were found in the proximal segments of the basal cerebral arteries.

Adolescent↗