Biomedical subjects

Hans Wilhelm

Publications and source records attributed to Hans Wilhelm.

7 recordsLinked to original sources

PubMed2006

Transcranial sonography of the third ventricle and cognitive dysfunction in HIV patients.

BACKGROUND: Although the incidence and prevalence of dementia associated with human immunodeficiency virus (HIV) infection has decreased since the introduction of highly active antiretroviral therapy, cognitive dysfunction remains one of the most prevalent factors severely affecting quality of life in patients with HIV. Previous magnetic resonance imaging (MRI) studies showed a correlation between brain atrophy, enlargement of the ventricles and cognitive impairment in HIV patients. OBJECTIVE: To investigate the usefulness of transcranial sonographic (TCS) measurement of the third ventricle in detection of brain atrophy in HIV patients and the correlation with neuropsychological deficits. METHODS: We examined 47 HIV patients and 40 healthy age-matched controls with TCS, neuroimaging (cranial MRI or computed tomography) and a neuropsychological test battery. RESULTS: The third ventricle was significantly larger in patients than in healthy controls and correlated significantly with duration of HIV, Center of Disease Control (CDC) stage, CD4 lymphocytes and distinct cognitive and motor deficits. CONCLUSION: TCS cannot replace neuroimaging but is a valuable method in the detection of brain atrophy and follow-up of HIV patients at risk or with a recent diagnosis of HIV encephalopathy.

Adult↗

PubMed2006

Carotid intima-media thickness in HIV-infected individuals: relationship of premature atherosclerosis to neuropsychological deficits?

BACKGROUND: Intima-media thickness (IMT) measured by extracranial duplex sonography is a surrogate marker for atherosclerosis. It is well known that IMT is greater in HIV patients than in age-matched healthy controls due to HIV- induced endothelial damage and metabolic side-effects of antiretroviral therapy. However, it remains unclear whether atherosclerosis has an additional impact on cognitive function in HIV patients. Therefore, the objective of this study was to investigate the correlation between IMT and neuropsychological deficits in HIV patients. METHODS: 47 HIV patients and 40 age-matched healthy controls were examined by extracranial ultrasound 2 and 3 cm before the flow divider to evaluate differences in IMT. Possible neuropsychological deficits in HIV patients were assessed using a battery of 10 neuropsychological tests. Results of neuropsychological tests and markers of disease severity were correlated with IMT in HIV patients. RESULTS: IMT was significantly greater in patients than in healthy controls (p < 0.001). However, none of the neuropsychological tests correlated significantly with IMT measurements in HIV patients. There was only a weak correlation between deficits in attention and IMT in HIV patients (r = 0.44; p = 0.005), which was non-significant after correction for multiple comparisons. Markers of disease severity (CD4 cell count, HIV load in plasma, duration of HIV disease) did not correlate with IMT either. CONCLUSION: IMT was greater in HIV patients compared to age-matched controls but it appears that premature atherosclerosis has no additional impact on the evolution of neuropsychological deficits in HIV patients. IMT did not correlate with the severity of immunodeficiency.

Adult↗

PubMed2005

Attention and memory dysfunctions in mild multiple sclerosis.

This study investigated the relationship between clinical symptoms and cognitive dysfunction in multiple sclerosis. Cognitive dysfunction and visual evoked potentials (VEPs) were studied in patients free of physical disability and mildly to moderately disabled patients with multiple sclerosis (MS). Disability-free patients (EDSS < or = 1.5; n = 13), mildly to moderately disabled patients (EDSS ranging from 2 to 6; n = 13) and a healthy matched control group (n = 16) were examined with respect to attention, verbal and nonverbal memory and early visual processing (VEPs). Disability-free patients showed mild impairments on phasic alertness and divided attention. Deficits were more pronounced in mildly to moderately disabled patients who were additionally impaired with respect to non-verbal memory. Despite adequate visual acuity, one half of all patients showed abnormal VEP latencies for both eyes at the same time. The findings suggest that cognitive deficits are already present in multiple sclerosis even in the absence of physical disability. Even with normal visual acuity, perceptual impairments should be considered as part of the CNS affection.

Adult↗

PubMed2005

Small ischemic brain lesions after cardiac valve replacement detected by diffusion-weighted magnetic resonance imaging: relation to neurocognitive function.

OBJECTIVE: Following coronary artery bypass graft surgery, some studies using magnetic resonance imaging (MRI) have demonstrated new small ischemic brain lesions in patients without apparent neurological deficits. We aimed to prospectively evaluate brain injury after cardiac valve replacement using MRI and to determine the relationship to neurocognitive function. METHODS: Thirty patients with a mean age of 64.9+/-9.8 years (range, 32-82, 12 female) receiving cardiac valve replacement (aortic valve replacement [AVR], n = 24; mitral valve replacement [MVR], n = 2; AVR and MVR, n = 2; AVR and mitral valve repair, n = 2) were investigated. Study protocol included neurological examination, comprehensive neuropsychological assessment and diffusion-weighted (DW) MRI. The investigations were performed before surgery and 5 days and 4 months after surgery. RESULTS: Postoperative DW MRI detected new focal brain lesions in 14 patients (47%). No patient revealed a focal neurological deficit. Six patients (43%) had multiple (> or = 3) lesions (range, 1-7). Lesion volume ranged from 50-500 mm3 except 1 territorial infarct of 1900 mm3. Of a total of 41 lesions, 27 (66%) were located in the right hemisphere and 32 in a subcortical location. By 5 days postoperatively, significant neurocognitive decline was observed in 5 of 13 tests affecting memory, attention and rate of information processing. By 4 months, dysfunction had recovered in all cognitive areas. The presence of new ischemic lesions was not associated with neurocognitive decline at discharge. There was also no significant correlation between clinical and operative variables and the presence of new DW lesions or neuropsychological outcome. CONCLUSIONS: Following cardiac valve replacement, new small ischemic brain lesions were detected by diffusion-weighted MRI. Neurocognitive decline was present early after operation, but resolved within 4 months. A correlation of new ischemic lesions to postoperative cognitive dysfunction or clinical variables was not found.

Adult↗

PubMed2004

Evaluation of brain injury after coronary artery bypass grafting. A prospective study using neuropsychological assessment and diffusion-weighted magnetic resonance imaging.

OBJECTIVE: Neurocognitive dysfunction is a common complication after cardiac surgery with cardiopulmonary bypass (CPB). Studies using magnetic resonance imaging (MRI) have demonstrated that new focal brain lesions can occur after coronary artery bypass grafting (CABG), even in patients without apparent neurological deficits. Diffusion-weighted MRI is superior to conventional MRI and allows for sensitive and early detection of ischemic brain lesions. We prospectively investigated cerebral injury early and 3 months after CABG using diffusion-weighted MRI and related the findings to clinical data and neurocognitive functions. METHODS: Twenty-nine patients [67.6+/-8.6 (52-85) years, 5 females] undergoing elective CABG with CPB were examined before surgery, at discharge and 3 months after surgery. A battery of standardized neuropsychological tests and questionnaires on depression and mood were administered. Conventional and diffusion-weighted MRI of the brain was performed and new lesions were analyzed. Clinical characteristics, neuropsychological test performance and radiographic data were collected and compared. RESULTS: There was no major neurological complication after CABG. Thirteen patients (45%) exhibited 32 new ischemic lesions on postoperative diffusion-weighted MRI. The lesions were small, rounded and equally dispersed in both hemispheres. Eight patients had at least two lesions. At discharge, significant deterioration of neuropsychological performance was observed in 6 of the 13 tests compared to baseline assessment. By 3 months postoperatively, 5 of the 6 tests returned to preoperative levels. Verbal learning ability, however, remained impaired. The presence of new focal brain lesions was not associated with impaired neuropsychological performance. There was also no correlation between clinical variables, intraoperative parameters and postoperative complications and MRI findings. CONCLUSIONS: Although neurocognitive decline after CABG is mostly transient, memory impairment can persist for months. New ischemic brain lesions on postoperative diffusion-weighted MRI do not appear to account for the persistent neurocognitive decline.

Aged↗

PubMed2003

Long-term survival following radiotherapy and cytarabine chemotherapy for sporadic primary central nervous system lymphoma.

PURPOSE: To analyze the long-term results following whole brain radiotherapy (WBRT) with sequential intrathecal (i.th.) cytosine arabinoside (Ara-C) +/- intravenous (i.v.) Ara-C in patients with primary central nervous system lymphoma (PCNSL). PATIENTS AND METHODS: 14 patients were treated between July 1987 and August 1995. All had sporadic PCNSL with proven histology of high-grade CNS lymphoma (twelve diffuse large-cell B-lymphomas, one lymphoblastic lymphoma, one large T-cell lymphoma). Patients were treated with two to four cycles of induction chemotherapy (40 mg/m2 Ara-C i.th.), four patients received additional Ara-C i.v. (150 mg/m2, d1-4). WBRT was administered using 1.8-Gy fractions. Intrathecal chemotherapy was planned afterwards in 4-week intervals for 6 months. Posttreatment neurocognitive evaluations were performed in two long-term survivors. RESULTS: Two of four patients who received i.v. and i.th. induction chemotherapy showed progressive disease, and irradiation was started immediately. Six of 14 patients received 50.4 Gy WBRT, four patients had WBRT up to 39.6 Gy followed by a 10.8-Gy boost. Five patients died early during therapy either due to a decline of the general medical condition or progressive disease. Median survival was 41 months (95% confidence interval: 6-79 months), survival at 3 and 5 years was 59% and 42%, respectively. Six patients survived for 3 years, two younger patients are still alive (> 12 years). They show only slightly impaired neurocognitive functions without clinical relevance. CONCLUSION: This WBRT-based protocol with i.th. meningeal prophylaxis using Ara-C +/- i.v. Ara-C yields substantial long-term survival with moderate toxicity. The value of i.v. chemotherapy is currently being investigated in prospective studies.

Adult↗

PubMed2002

Clinical outcome and neuropsychological deficits after right decompressive hemicraniectomy in MCA infarction.

BACKGROUND AND PURPOSE: The purpose of this study was to analyse in detail the functional outcome and the neuropsychological deficits in patients with space-occupying infarction of the non-dominant hemisphere one year after surgery. METHODS: Postoperative complications and retrospective consent to surgery were assessed in a semi-structured interview in 26 patients. Functional outcome was measured with the Barthel-Index (BI) and Rankin-Scale. Neuropsychological tests in 14 patients focused on visuo-spatial and visuo-constructive abilities, attention, spatial span and self-rated mood. RESULTS: The one-year survival rate was 69 % (18 of 26). The functional outcome was good (BI >/= 90) in 3 patients, fairly good (BI 75-85) in 6, moderate (BI 30-70) in 6, and poor (BI 0-25) in 3 patients. Age was an independent predictor of outcome, patients above 52 years had a BI of 50 or below. Neuropsychological tests (14 of 18) showed profound attention deficits in all patients, and visuo-spatial and visuo-constructive deficits in patients with lower formal education. Retrospectively, 4 of 18 patients would not give consent to surgery again, mostly because of the bad quality of life postoperatively. CONCLUSION: Older patients do not seem to benefit from decompressive hemicraniectomy; more than half of the surviving younger patients have a good outcome and live independently. Attention deficits are prominent in all patients; visuo-spatial and constructive deficits are less pronounced in patients with higher formal education. Retrospective agreement to decompressive hemicraniectomy is high in patients with good functional outcome.

Adolescent↗