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Marianne Juhler

Publications and source records attributed to Marianne Juhler.

7 recordsLinked to original sources
PubMed2006

Evaluation of the lumbar and ventricular infusion test in the diagnostic strategy of pediatric hydrocephalus and the therapeutic implications.

AIM: To evaluate the infusion test as a diagnostic tool behind the choice of intervention in pediatric hydrocephalus. MATERIALS AND METHODS: Intracranial pressure (ICP) measurement and infusion test were performed intraventricularly, by lumbar route, or combined in 40 consecutive children as a part of the standard diagnostic program in 1996-1999. RESULTS: The median age was 18.5 months, ranging from 2 weeks to 13 years. In the subgroup of patients with radiological aqueductal stenosis (N=14), mean lumbar/intraventricular ICP was 13 (3-35)/10 (2-27). Mean lumbar/ventricular R(out) were 18 (4-49)/17 (6-37). For patients with radiological communication between the third and fourth ventricles (N=14), the mean lumbar/intraventricular ICP was 11 (7-17)/9 (1-16). Mean lumbar/ventricular R(out) were 8 (3-11)/8 (4-12). A total of 13 patients had a shunt insertion, 10 had an endoscopic third ventriculostomy (ETV), 5 had endoscopic fenestration of a cyst, and 12 had no surgery. Of the patients initially treated with EVT, 50% had a shunt insertion shortly after. For communicating hydrocephalus, 75% of the patients initially not operated based on normal R(out) values ended up having a shunt insertion. DISCUSSION: R(out) has doubtful value as an indicator for conducting an operation or not and in the choice between EVT and shunt in children. This should be interpreted in the light of a growing understanding of hydrocephalus on a molecular level.

Adolescent↗
PubMed2006

A report of nine newborns with congenital brain tumours.

BACKGROUND: Although rare, brain tumours represent one of the relatively larger groups of congenital neoplasias. Most studies on congenital neoplastic disease deal with several types of neoplasms and are dominated by leukaemias, retinoblastomas and systemic solid tumours. Few studies are dedicated to congenital brain tumours. We present nine newborns (four boys and five girls) who were diagnosed with congenital brain tumours during the 8-year period 1 January 1992-31 December 1999 at our institution, which covers all paediatric neuro-oncology cases for Eastern Denmark. EPIDEMIOLOGY: Two of the cases were referred from Western Denmark for surgery, and were therefore excluded from the calculation of incidence. During the same period, a total of 172 children below the age of 15 years were diagnosed as having primary central nervous system tumours. The seven remaining congenital cases thus represent 4% of all paediatric brain tumour cases in the area (95% confidence interval 1.7-8.3%). The population of the referral area is 2.383x10(6), and based on the total number of living births, the incidence of congenital brain tumour was calculated to be 2.9 per 100,000 live births. The ages of the mothers were 28-33 years, corresponding to the present mean age of 31 years for Danish primipara. The gestational age varied between 35 and 42 weeks, and the birth weights were 3,044-4,790 g. RISK FACTORS: Two patients with p53-related glioblastoma multiforme (GBM) had relatives with p53-related neoplasms. In one case, the mother was treated for cancer of the ovary with surgery and chemotherapy 2 months before conception. CLINICAL FEATURES: In five of the cases, brain abnormality was suspected antenatally. The clinical features of the newborns were limited to enlarged head circumferences, associated hydrocephalus, and asymmetric skull growth. DIAGNOSIS AND TREATMENT: Three babies were treated with complete tumour resection. In the remaining six cases, a guided or open biopsy to obtain histology was made after CT/MRI imaging. The histological diagnoses were teratoma in four cases, GBM in two cases, anaplastic astrocytoma in two cases and, finally, haemangioma capillare in one case. OUTCOME: Four of the patients (44%) are still alive, including two patients with totally resected combined orbital/intracranial teratomas, one patient with a totally resected haemangioma and one patient with anaplastic astrocytoma who did not receive any treatment apart from supportive care. The survival lengths of the five neonates who died varied between 1 day and 51 days.

Brain Neoplasms↗
PubMed2006

Effect of graded hyperventilation on cerebral metabolism in a cisterna magna blood injection model of subarachnoid hemorrhage in rats.

In subarachnoid hemorrhage (SAH) with cerebrovascular instability, hyperventilation may induce a risk of inducing or aggravating cerebral ischemia. We measured cerebral blood flow (CBF) and cerebral metabolic rates of oxygen (CMRO2), glucose (CMRglc), and lactate (CMRlac) at different PaCO2 levels after experimental SAH in rats (injection of 0.07 mL of autologous blood into the cisterna magna). Four groups of Sprague-Dawley male rats were studied at predetermined PaCO2 levels: group A: normocapnia (5.01-5.66 kPa [38.0-42.0 mm Hg]); group B: slight hyperventilation (4.34-5.00 kPa [32.5-37.5 mm Hg]); group C: moderate hyperventilation (3.67-4.33 kPa [27.5-32.4 mm Hg]); group D: profound hyperventilation (3.00-3.66 kPa [22.5-27.4 mm Hg]). Each of the four groups included eight rats with SAH and eight sham-operated controls. CBF was determined by the intracarotid Xe method; CMRo2, CMRglc, and CMRlac were obtained by cerebral arteriovenous differences. In both SAH rats and controls, hyperventilation decreased CBF in proportion to the decrement in PaCO2 without affecting either CMRO2, CMRglc, or CMRlac. In groups C and D, CBF decreased by 20%-35%, but CMRs were maintained by a compensatory increase in oxygen extraction fraction (OEF). The results show that even profound hyperventilation in this model of SAH is associated with an adequate increase in OEF so that CMRs of oxygen, glucose, and lactate remain similar to levels observed in normocapnic conditions.

Animals↗
PubMed2003

Effects of cerebrospinal fluid acidity on cerebral blood flow and autoregulation in rats.

Using a ventriculocisternal perfusion method, the effects of cerebrospinal fluid (CSF) acidity of nonrespiratory origin on cerebral blood flow (CBF) and autoregulation of CBF were investigated. Three groups (six rats each) were studied: one group of sham operated rats, one control group with ventriculocisternal perfusion at normal pH (mean inflow pH +/- SD, 7.42 +/- 0.02), and one experimental group with ventriculocisternal perfusion at low pH (mean inflow pH +/- SD, 6.81 +/- 0.01). CBF was measured by the intracarotid xenon 133 method. Autoregulation was studied by repetitive measurements of CBF during an initial increase and then stepwise reduction of mean arterial blood pressure (MABP). No difference in CBF was found between sham operated and control rats with unperturbed pH (mean cisternal outflow pH +/- SD, 7.42 +/- 0.03) of CSF), and autoregulation was intact in both groups. In the experimental group, the mean CBF +/- SD was increased by 58%, from 127 +/- 33 mL/(100 g.min) before ventriculocisternal perfusion to 201 +/- 54 mL/(100 g.min) (P <.00001) during perfusion with acid CSF (mean cisternal outflow pH +/- SD, 7.23 +/- 0.04). In this group, the relationship between CBF and MABP was linear, thus indicating disrupted autoregulation. In conclusion, CSF acidity significantly increases CBF and impairs autoregulation of CBF.

Animals↗
PubMed2002

A single subcutaneous bolus of erythropoietin normalizes cerebral blood flow autoregulation after subarachnoid haemorrhage in rats.

Systemic administration of recombinant erythropoietin (EPO) has been demonstrated to mediate neuroprotection. This effect of EPO may in part rely on a beneficial effect on cerebrovascular dysfunction leading to ischaemic neuronal damage. We investigated the in vivo effects of subcutaneously administered recombinant EPO on impaired cerebral blood flow (CBF) autoregulation after experimental subarachnoid haemorrhage (SAH). Four groups of male Sprague-Dawley rats were studied: group A, sham operation plus vehicle; group B, sham operation plus EPO; group C, SAH plus vehicle; group D, SAH plus EPO. SAH was induced by injection of 0.07 ml of autologous blood into the cisterna magna. EPO (400 iu kg(-1) s.c.) or vehicle was given immediately after the subarachnoid injection of blood or saline. Forty-eight hours after the induction of SAH, CBF autoregulatory function was evaluated using the intracarotid (133)Xe method. CBF autoregulation was preserved in both sham-operated groups (lower limits of mean arterial blood pressure: 91+/-3 and 98+/-3 mmHg in groups A and B, respectively). In the vehicle treated SAH-group, autoregulation was abolished and the relationship between CBF and blood pressure was best described by a single linear regression line. A subcutaneous injection of EPO given immediately after the induction of SAH normalized autoregulation of CBF (lower limit in group D: 93+/-4 mmHg, NS compared with groups A and B). Early activation of endothelial EPO receptors may represent a potential therapeutic strategy in the treatment of cerebrovascular perturbations after SAH.

Animals↗