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Andreas Otte

Publications and source records attributed to Andreas Otte.

At least 19 recordsLinked to original sources
PubMed2006

Brain imaging tools in neurosciences.

In this chapter brain imaging tools in neurosciences are presented. These include a brief overview on single-photon emission tomography (SPET) and a detailed focus on positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). In addition, a critical discussion on the advantages and disadvantages of the three diagnostic systems is added. Furthermore, this article describes the image analysis tools from visual analysis over region-of-interest technique up to statistical parametric mapping, co-registration methods, and network analysis. It also compares the newly developed combined PET/CT scanner approach with established image fusion software approaches. There is rapid change: Better scanner qualities, new software packages and scanner concepts are on the road paved for an amply bright future in neurosciences.

Animals↗
PubMed2005

Good clinical practice: historical background and key aspects.

Clinical research trials (both academic and industry sponsored) are increasingly playing a role in various medical disciplines, including younger fields of clinical trial interest, such as nuclear medicine research. Knowledge for and compliance with good clinical practice (GCP) is essential for anyone involved. In this review article, key aspects of GCP and the responsibilities of investigators, monitors and sponsors are described. In addition, a comprehensive overview of the historical background on the development of GCP from the US Pure Food and Drugs Act of 1906 over the Nuremberg Code, the Kefauver-Harris Amendments and the Declaration of Helsinki until now is given. Knowledge of the historical background may help understand the developments in GCP.

Clinical Trials as Topic↗
PubMed2004

Cognitive neuroactivation using SPECT and the Stroop Colored Word Test in patients with diffuse brain injury.

Psychomotor slowing in patients with diffuse brain injury frequently underlies impaired cognitive performance on neuropsychological tests, for example, the Stroop Colored Word test. The aim of the present study was to determine the neural basis associated with performance on the Stroop interference subtask in patients with diffuse brain injury. We hypothesized that patients would be slower than healthy controls, and that this would be associated with brain activations other than those seen in healthy subjects. Brain perfusion, using a split-dose activation paradigm with single photon emission tomography (SPECT) and the Stroop test, was assessed in 9 patients with diffuse brain injury. The Stroop interference score was calculated as a behavioral parameter, and functional imaging data were analyzed with statistical parametrical mapping (SPM99) to determine significant voxel-wise differences of activation between the control and the activation condition. Patients were impaired on the interference subtask of the Stroop test. Comparison of the SPECT data obtained during the activation condition with those obtained during the control condition by means of SPM showed significant activations in the left inferior parietal lobe, the right anterior cingulate extending into the right middle frontal gyrus and the right caudate, and the left posterior cingulate cortex. Patients with diffuse brain injury were slower than healthy controls on the interference subtask of the Stroop test, suggesting difficulty with resistance to distractions. This finding was associated with activation effects in posterior (mainly parietal) brain areas in addition with activation of previously observed anterior (mainly anterior cingulate) brain regions.

Adult↗
PubMed2004

Subjective sleep disturbance in patients with partial epilepsy: a questionnaire-based study on prevalence and impact on quality of life.

PURPOSE: This study was designed to assess whether sleep disturbance is more frequent among patients with partial seizures and what impact on quality of life (QoL) sleep disturbance may have on patients with partial seizures. METHODS: Questionnaire booklets were mailed to 1,183 patients from four Dutch clinics. Each patient was asked to find two age- and gender-matched controls to complete the same set of questionnaires [Sleep Diagnosis List (SDL), Medical Outcomes Study (MOS)-Sleep Scale, Groningen Sleep Questionnaire, Epworth Sleepiness Scale, and the SF-36 Health Survey]. The prevalence of sleep disturbance, based on the SDL, was compared between those with partial epilepsy and controls. Mean scores on sleep and the SF-36 Physical (PCS) and Mental (MCS) Component Summary scales were compared. RESULTS: Responses from 486 patients and 492 controls were analyzed. Respondents with partial epilepsy had a highly significant, twofold higher prevalence of sleep disturbance compared with controls (38.6 vs. 18.0%; p < 0.0001). Most sleep-disorder subscales showed significant abnormalities in respondents with epilepsy, compared with controls. Mean SF-36 MCS and PCS scores were significantly lower in respondents with epilepsy compared with controls in both the strata with sleep disturbance and without (all p values <0.05). The presence of a sleep disturbance in respondents with epilepsy was associated with the greatest impairment in QoL. CONCLUSIONS: Sleep disturbance is more than twice as prevalent in persons with partial epilepsy compared with controls, and most domains of sleep are significantly disturbed. Persons with partial epilepsy have significant QoL impairment, and sleep disturbance further compounds this.

Adult↗
PubMed2004

Renal toxicity after radionuclide therapy.

During the past 10 years, a variety of radiolabeled monoclonal antibodies, antibody fragments, and low-molecular- weight oncophilic peptides have been used to deliver radioactivity to target cells for therapeutic purposes. The high and persistent localization of several of these radiolabeled molecules in the kidneys raised concern about potential renal radiation toxicity compromising therapeutic effectiveness. In particular, radiolabeled peptides, such as yttrium-90-labeled synthetic somatostatin analogues, have initiated a discussion on the safety profiles of the various somatostatin derivatives in recent clinical trials. In general, the toxicity risk seems to depend on the characteristics of the oncophilic molecule, such as the molecular weight, electric charges and clearance pathways as well as the chemical and physical characteristics of the applied radionuclide. Encouraging results for the prevention of radiation-induced renal damage by radiolabeled peptides have been obtained by co-infusion of positively charged amino acids. The available literature on nephrotoxicity after radiolabeled peptide therapy is reviewed, and therapeutic options that have become available as a result of greater insights into putative pathogenic mechanisms are discussed.

Humans↗
PubMed2004

The hospital organization of the future.

The future of hospital Nuclear Medicine is triggered by the hospital organisation itself. In general, the hospital organisation of the present requires substantial changes in order to be competitive, economical, and abreast of the rapid progresses in medical developments and patient management. It also must be flexible to changes in health politics. In this special report an organisational hospital structure is outlined which may help encounter the challenging hospital future. Some hospitals have already implemented convincing changes, whereas others are far behind.

Delivery of Health Care↗
PubMed2003

Nuclear medicine imaging for the assessment of primary and recurrent head and neck carcinoma using routinely available tracers.

This article reviews the literature on the use of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) and thallium-201, technetium-99m sestamibi and technetium-99m tetrofosmin single-photon emission tomography (SPET) for the diagnosis and staging of primary and recurrent squamous cell carcinoma of the head and neck (SCCHN). A search of the MEDLINE and CancerLit databases covering articles entered between 1989 and February 2003 was performed. In the case of FDG PET, only full-ring PET studies that included comparison with conventional morphological imaging were considered. Due to the wide variation in methodology, a straightforward meta-analysis of FDG PET literature was impossible. Instead, indicative summary receiver-operating curves of FDG PET and morphological imaging techniques were generated and a paired comparison of the sensitivities and specificities of FDG PET and morphological imaging performed. Compared with conventional morphological imaging, FDG PET proved as sensitive and specific for the detection of primary SCCHN but more sensitive and specific for the detection of cervical lymph node involvement (CLNI) and recurrence of SCCHN. Additional studies addressing the role of FDG PET in screening for distant metastases and synchronous primary tumours are mandatory. Following negative conventional evaluations, FDG PET identifies occult primary tumours in 20-50% of patients presenting with CLNI. As regards the use of 201Tl, 99mTc-sestamibi and 99mTc-tetrofosmin, more studies are required to define whether these imaging agents could form part of the current diagnostic armamentarium in SCCHN patients. It is concluded that FDG PET either is superior to or offers added value when compared with conventional morphological imaging techniques for the purpose of diagnosis and staging of primary and recurrent SCCHN.

Carcinoma, Squamous Cell↗
PubMed2003

Estimates of regional cerebral blood flow and 5-HT2A receptor density in impulsive, aggressive dogs with 99mTc-ECD and 123I-5-I-R91150.

Impulsive aggression in dogs has an important impact on human public health. Better insight into the pathophysiology of this phenomenon could lead to more adequate diagnosis and treatment. Indirect in vivo research on peripheral body fluids and post-mortem studies in impulsive animals and humans indicate a deficient serotonergic system in general and disturbances in the serotonin-2A (5-HT2A) receptor in particular. In this study, brain perfusion and the 5-HT2A receptors were examined in impulsive, aggressive dogs, in comparison with a group of normally behaving animals. In order to decide which dogs to include in this study, owners were asked to describe the general behaviour of the dogs, the circumstances in which aggression occurred and their conduct during aggressive acts. Finally, 19 dogs were retained for this study, showing, according to different behavioural specialists, disinhibited dominance aggression. Functional imaging studies were performed on all these dogs. Single-photon emission tomography (SPET) was used to measure regional brain perfusion using technetium-99m labelled ethyl cysteinate dimer (ECD). The 5-HT2A receptor binding properties were investigated using the selective radioligand iodine-123 labelled 5-I-R91150. A significant increase in uptake of the 5-HT2A radioligand was noted in all cortical areas. No significant alterations were found in regional cortical perfusion, indicating that the increased binding index was not a consequence of increased tracer delivery. This study supports a role for the serotonergic system in canine impulsive aggression.

Aggression↗
PubMed2003

[Neuropsychiatric involvement in systemic lupus erythematosus. Part 2: diagnostic and therapy].

BACKGROUND: The diagnosis of neuropsychiatric lupus erythematosus (NPSLE) can be difficult and has to be differentiated from neurologic complications that result from hypertension, drugs, infection, uremia, and metabolic changes. DIAGNOSTICS: There is no single test which is diagnostic. Therefore, the clinical presentation, serologic tests and neuroimaging techniques have to be combined to support the diagnosis of cerebral lupus. Magnetic resonance imaging (MRI) is routinely used with a sensitivity of 50-87%. However, the abnormalities such as white matter lesions or brain atrophy are nonspecific and were also found in asymptomatic patients (16-52%). A negative MRI result does not exclude a diagnosis of cerebral lupus. Antibodies against phospholipids are an important immunoserologic marker due to the close association with thromboembolic events. Echocardiography and cerebrospinal fluid examination should be added to rule out cardiac embolic disease and CNS infection. Functional brain imaging techniques such as single-photon emission computed tomography, positron emission tomography, magnetization transfer imaging or magnetic resonance spectroscopy may be helpful especially in patients with unconspicuous MRI, but the findings are not SLE-specific. THERAPY: The treatment of cerebral lupus is empiric, due to a lack of randomized studies. Inflammatory brain lesions are treated with corticosteroids and immunosuppressive drugs (e. g., cyclophosphamide). Anticoagulant therapy with coumarins (at a target INR of 3.0-3.5) is recommended in cases of thrombotic events associated with antiphospholipid antibodies. However, no studies exist on patients with arterial thrombosis, including strokes, supporting this target INR.

Adrenal Cortex Hormones↗
PubMed2003

The dilemma of being a physician-patient.

Being either a physician or a relative to a physician on the occasion of having a disease needing help from another physician, the physician-patient situation, can trigger some problems which are different from the normal doctor-patient relationship. Some aspects of this are an incorrect diagnostic approach (either hyper- or hypo-diagnostics) and an inadequate therapeutic regimen. Others are mainly based on the peer situation of the two parties involved. Awareness of the special physician-patient situation in the treating physician could be one step out of the dilemma.

Attitude↗