Multifocal visual evoked potentials-a method study of responses from small sectors of the visual field.

Objective: A method study of the mfVEP technique to establish a standardised way to identify stable response components from small areas in all parts of the visual field and a test-retest reliability study. Methods: MfVEP was recorded from 26 healthy volunteers. Results: Two response components could be clearly identified. The latencies corresponded to those of the traditional VEP response (N75 and P100). The visual field was divided into 12 sectors. A characteristic pattern was obtained. Component I was mainly negative in the upper sectors and positive in the lower sectors. Component II was positive in the upper sectors and negative in the lower ones. Most of the sectors with missing responses were the ones adjacent to the horizontal meridian, corresponding to the phase reversals. In a test-retest reliability study, the amplitude and latency measurements of the second test were plotted against those of the first test. Correlation coefficients between 0.84 and 0.93 were obtained. Conclusions: The mfVEP allows a reliable quantification of two response components from small parts of the visual field. Significance: This paper suggests that mfVEP could be a valuable supplement to the traditional VEP for exploring restricted parts of the visual pathways

Lack of orthostatic symptoms in dementia patients with orthostatic hypotension.

Purpose: Orthostatic hypotension (OH) is common and increases with age. OH is part of the autonomic dysfunction in dementia with Lewy bodies (DLB). Commonly OH is diagnosed when the patient falls which is a risk factor of premature death. Our objective was to systematically investigate the clinical symptoms associated with measurement of OH in different neurodegenerative dementias and normal controls (NC). Methods: 154 patients [50 DLB, 50 Alzheimer’s disease (AD), 54 AD and vascular components (ADvasc)] were examined with systolic and diastolic blood pressure measurements in supine position, immediately after standing up and after 1, 3, 5 and 10 min of standing. They were compared with 50 NC. Orthostatic symptoms were registered according to a predefined protocol. Results: Twenty-seven percent of all the investigated individuals reported OH symptoms during the measurement while 43% fulfilled the criteria of OH. Sixty-three percent of orthostatic patients did not have any symptoms during the measurement. The prevalence of any orthostatic symptoms during the measurement differed significantly (p<0.001) between the diagnostic groups with 40% in DLB patients, 37% in ADvasc, 28% in AD and 2% in NC. The most frequent symptom was dizziness 13.7%. Conclusions: Classical orthostatic symptoms are absent in the majority of dementia patients with OH. The orthostatic reaction must therefore be routinely measured in this patient group. This is particularly important for patients with DLB where falls as a result of OH are common

Evaluation of Systolic and Diastolic Hypotension in Dementia with Lewy Bodies and Alzheimer’s Disease.

BACKGROUND: Orthostatic hypotension (OH) can be seen in as many as 30% to 50% of the elderly population as well as in dementia. OH is part of the autonomic dysfunction in dementia with Lewy bodies (DLB) and prevalent in the majority of these patients. It is also suggested to be a negative prognostic factor for survival in DLB. A detailed interpretation of the 10-minute orthostatic blood pressure measurement has shown prolonged orthostasis in DLB compared with other dementias. The type of OH (systolic and diastolic) has not been separately investigated in different dementias. OBJECTIVES: The aims of this study were to analyze the type of orthostatic hypotension, systolic and/or diastolic, in different dementia groups compared with normal controls. PATIENTS AND METHODS: One-hundred fifty-six individuals, 52 with DLB, 50 with Alzheimer’s disease (AD), 54 AD with vascular components (ADvasc), and 62 normal controls, were included. As part of each patient’s routine clinical dementia investigation, systolic and diastolic blood pressure measurements were examined in the supine position, immediately after standing up, and after 1, 3, 5, and 10 minutes of standing. OH was defined as a blood pressure drop of 20 mmHg systolic or 10 mmHg diastolic, and the type of OH—systolic, diastolic or both—was defined. RESULTS: Orthostatic hypotension was severely underdiagnosed before the dementia investigation with only 2% to 4% in the dementia groups, while we found that 69% of DLB, 50% of ADvasc, 38% of AD, and 13% of normal controls had OH. A combination of systolic and diastolic OH was the most common type of OH both in the DLB (67%) and ADvasc (48%) groups, while systolic OH was the most common type in AD (63 %) as well as in normal controls (63%). Mini Mental State Examination scores differed significantly (P < 0.001) between the group with no OH (25.2 ± 4.8) and the group with combined systolic and diastolic OH (22.0 ± 4.8). CONCLUSION: Patients with DLB showed a greater proportion of combined systolic and diastolic hypotension. This might suggest a more complex OH than in patients with AD or elderly controls, possibly exacerbating the clinical picture in DLB. Further investigations of the relevance of these findings and the relation to clinical symptoms are needed

Exposure of infants to budesonide through breast milk of asthmatic mothers

Background: Maintenance treatment with inhaled corticosteroids is often required for asthmatic nursing women. Data on the transfer of inhaled corticosteroids from plasma to breast milk and the subsequent exposure of the breast-feeding infant has been unavailable. Objective: We sought to assess budesonide concentrations in milk and plasma of asthmatic nursing women receiving maintenance treatment with the Pulmicort Turbuhaler and estimate the exposure of their breast-fed infants. Methods: Milk and plasma samples were collected up to 8 hours after dosing from 8 mothers receiving budesonide maintenance treatment (200 or 400 mu g twice daily). Pharmacokinetic parameters were calculated from budesonide milk and plasma concentrations. Infant exposure was estimated based on average milk budesonide concentrations. A single blood sample was obtained from 5 infants close to expected infant maximum concentration. Results: Budesonide concentrations in milk reflected those in maternal plasma, supporting passive diffusion of budesonide between plasma and milk, and was always lower than that in plasma. The mean milk/plasma ratio was 0.46. The estimated daily infant dose was 0.3% of the daily maternal dose for both dose levels, and the average plasma concentration in infants was estimated to be 1/600th of the concentrations observed in maternal plasma, assuming complete infant oral bioavailability. Budesonide concentrations in infant plasma samples were all less than the limit of quantification. Conclusion: Maintenance treatment with inhaled budesonide (200 or 400 mu g twice daily) in asthmatic nursing women results in negligible systemic exposure to budesonide in breast-fed infants. Clinical implications: These data support continued use of inhaled budesonide during breast-feeding