Karl Dantendorfer

A study of the effects of patient anxiety, perceptions and equipment on motion artifacts in magnetic resonance imaging

We investigated to see if motion artifacts (MA) occurring in magnetic resonance imaging (MRI) are related to prescan anxiety measures and test the feasibility of identifying patients at risk for the development of MA before scanning. Furthermore, to determine a possible influence of constructional differences between a 1.5 and a 0.5 tesla scanner on the frequency of MA. Two hundred and ninety-seven first time MRI patients were surveyed before and after imaging with anxiety and attitude questionnaires. Frequency and impact on diagnostic quality of MA were documented. 12.8% of all scans showed MA not related to normal body pulsations. In 6.4% the diagnostic quality was impaired. Constructional differences did not influence the frequency of MA. Also, anxiety as determined with the most common anxiety measuring instrument was not related to the development of MA. Concern about the technical apparatus identified 70.6% of all individuals developing MA. Patients at risk for the development of MA can be identified prior to scanning. It seems necessary to further develop reliable methods to detect them and to evaluate strategies to prevent MA.

High frequency of EEG and MRI brain abnormalities in panic disorder.

The frequency and quality of brain abnormalities in panic disorder (PD) were assessed with magnetic resonance imaging (MRI). The use of electroencephalography (EEG) to detect PD patients with a high probability of morphologic brain abnormalities was also explored. Consecutive PD patients (n = 120) were screened with routine EEG examinations and were divided into the following subgroups on the basis of their EEG findings: patients with non-epileptic EEG abnormalities (EEG-A group, n = 28), matched patients with normal EEG results (EEG-N group, n = 28) and matched healthy controls (n = 28). PD patients showed a higher than expected rate of non-epileptic EEG abnormalities (29.2%; 35 of 120). EEG screening was effective in identifying patients with a high probability of morphologic brain abnormalities. MRI abnormalities were found in 60.7% of the EEG-A patients, 17.9% of the EEG-N patients, and only 3.6% of the controls. A high frequency of septo-hippocampal abnormalities was found. Further research should focus on attempts to subtype PD on the basis of neuroanatomic and functional brain abnormalities.

Impaired conditional discrimination learning in schizophrenia.

Learning deficits have repeatedly been found in patients with schizophrenia. Eyelid conditional discrimination learning (ECDL) is a test of discriminative aversive conditioning and places minimal demands on motivation. An ECDL task was used to examine residual and paranoid type individuals with schizophrenia and age- and gender-equivalent healthy controls. In the experiment two differently colored light stimuli were randomly presented. Only one of the stimuli (in reinforced trials) was followed by an aversive airpuff to the cornea, as opposed to unreinforced trials where the stimulus was not followed by an aversive airpuff. Conditioned responses develop to both trial types during the course of the experiment. These conditioned responses consist of reflectory eyelid closures already upon light presentation. The patients showed significantly impaired conditional discrimination learning abilities. There was no significant difference between the results in the two schizophrenia subtypes. Patients failed to increase response frequencies on reinforced trials during the course of the experiment, while controls showed appropriate conditional discrimination ability. Thus the results show an impairment of adequate behavior modification in an aversive conditioning task in individuals with schizophrenia. It is concluded that ECDL might be a trait marker for schizophrenia.

Rapid decrease of serum cholesterol concentration and postpartum depression.

On the basis of studies of pharmacological reduction of serum lipid concentrations, it has been suggested that reduction in serum cholesterol and triglyceride is associated with occurrence of depressive symptoms, suicides, and violent deaths.1 2 3 Pregnancy induces a physiological rise in both serum cholesterol and triglyceride concentrations, with peak concentrations at term and a rapid decrease within a few days after delivery. Maternity blues is a common complication of the puerperium independent of obstetric variables.4 We postulated that the sudden fall in blood lipids after delivery could serve as a “natural” model to test the suggested association between serum lipids and mood. We studied 20 healthy primiparous women (mean age 25.3, SD 3.7, range 19-34 years) without substantial marital, health, or socioeconomic problems and without a history of psychiatric disorders who registered consecutively for obstetric …

Embarrassment about the first panic attack predicts agoraphobia in panic disorder patients

In order to find out whether contextual variables of the first panic attack and the persons reaction to it predict the development of agoraphobia in panic disorder patients, 60 patients with a DSM-III-R diagnosis of panic disorder with agoraphobia and 30 patients suffering from panic disorder without agoraphobia were interviewed about their first panic attack. Single comparisons between groups of agoraphobic and non-agoraphobic patients were carried out and a logistic regression model was applied. Occurrence of the first panic attack in public and the feeling of embarrassment were found to be significantly associated with the development of agoraphobia. It is concluded that eliciting this specific form of social concern at an early stage might help to identify patients at risk for later agoraphobia, which could, in turn, help to further specify early therapeutic interventions and concentrate therapeutic efforts on a high-risk group of panic disorder patients.

Placebo-Controlled Sleep Laboratory Studies on the Acute Effects of Zolpidem on Objective and Subjective Sleep and Awakening Quality in Nonorganic Insomnia Related to Neurotic and Stress-Related Disorder

Recent investigations in our sleep outpatient clinic demonstrated that 30% of patients exhibited organic and 70% nonorganic sleep disorders, with 41% showing as an additional diagnosis neurotic, stress-related, and somatoform disorders, 31% affective disorders and 15% mental and behavioral disorders due to psychoactive substance use. Thus, the aim of the study was to investigate the acute effects of the imidazopyridine zolpidem on objective and subjective sleep and awakening quality in the largest of the above-mentioned groups. In this single-blind, placebo-controlled cross-over study, 15 patients (9 females and 6 males aged 51.1 + 11.3 years) diagnosed as having nonorganic insomnia (ICD–10: F 51.0) related to neurotic and stress-related disorders (F 1.1:12, F 41.2:2 and F 43.2:1) were included. Objective and subjective sleep and awakening quality measures were investigated in 3 subsequent nights in the sleep laboratory (adaptation, baseline/placebo and zolpidem 10 mg night), utilizing clinical, polysomnographic, psychometric and psychophysiological methods. The drug-free patients were matched according to age and sex with 15 normal healthy controls (age 51.2 + 11.8 years). Statistical analysis of polysomnographic variables demonstrated a significant lengthening of the total sleep period (TSP) and total sleep time (TST), an improvement in sleep efficiency and a shortening of sleep latencies after zolpidem as compared with placebo. These changes were opposite to the differences between patients and controls. Concerning sleep architecture, zolpidem increased the length of S4 and S3 + S4 as compared with placebo. Subjective sleep and awakening quality and the thymopsychic variables drive, mood, affectivity and wakefulness in the morning showed no significant changes, as a significant improvement had already occurred from the adaptation to the baseline/placebo night. Noopsychic variables (attention, concentration, attention variability, numerical memory, fine motor activity, reaction time measures) showed similar findings. Moreover, subjective sleep and awakening quality, thymopsychic and noopsychic measures during baseline/placebo recordings did not differ significantly from normative data (except for fine motor activity). Psychophysiological measures did not show any significant alterations either, except for a decrease in systolic blood pressure in the evening. Conclusion: As compared with placebo, zolpidem induced a significant improvement in objective sleep quality, mainly by increasing TSP, TST and sleep efficiency and shortening sleep latencies, thereby normalizing the disorder of initiating and maintaining sleep. Deep sleep stages S3 + S4 increased (although at baseline/placebo these stages did not differ from controls), while S1, S2 and SREM did not change significantly. Subjective sleep and awakening quality as well as thymopsychic and noopsychic performance in the morning mainly showed a placebo and ‘first- night effect’ phenomenon in these patients. Thus, the changes induced by zolpidem were somewhat different from those after classical benzodiazepines.

Impaired Conditional Discrimination Learning in Social Phobia

Eyelid conditional discrimination learning (ECDL) is a test of discriminative aversive conditioning. It places minimal demands on motivation and was shown to selectively test temporal lobe function. Twenty-five unmedicated social phobia (SP) patients (mean age 29.5 ± 7.0 years), diagnosed according to DSM-IV criteria, and 25 age- and gender-matched healthy controls (HC, mean age 34.0 ± 8.6 years) were examined with an ECDL paradigm. In the experiment two differently colored stimuli are randomly presented. Only one of the stimuli (reinforced trial) is followed by an aversive airpuff to the cornea, as opposed to unreinforced trials not followed by an airpuff. Conditioned responses (CRs) consist of reflex eyelid closures already upon light presentation. HC as well as SP patients showed a significant difference between reinforced and unreinforced trials. In SP patients, CR frequency did not increase during the ECDL task, while HCs showed appropriate conditional discrimination ability. Thus the results indicate an impairment of adequate behavior modification in an aversive conditioning task in SP.

Gruppenpsychotherapie bei Panikstörung

Seit die Panikstorung im Diagnosticai and Statistical Manual of Mental Disorders (DSM-III) des Amerikanischen Psychiaterverbandes (APA 1980) definiert wurde, ist eine grose Zahl von pharmakotherapeutischen Studien erschienen. Dabei haben sich die alten trizyklischen und die neuen selektiv serotonergen Antidepressiva wie auch die Monoaminooxidase-Hemmkorper bei Anwendung uber 8 bis 12 Wochen als wirksam erwiesen; es kommt durch diese Medikamente zu einer deutlichen Reduktion der Panikattacken und der agoraphoben Symptomatik sowie der damit einhergehenden Behinderungen (Katschnig 1996). Auch aus dem psychotherapeutischen Bereich kamen nach und nach Studien, in denen belegt werden konnte, das bei Panikattacken zumindest kognitive Therapie auserst wirksam ist (Margraf et al. 1993). Bis heute gibt es nur wenige randomisierte Vergleichsstudien, die Pharmakotherapie und Psychotherapie miteinander vergleichen. In einer der am besten geplanten Untersuchungen, der von Clark und Mitarbeitern (1994), zeigte sich, das sowohl medikamentose als auch kognitive Therapie wirksam ist, nach Ende der Therapie kognitive Therapie jedoch einen persistierenderen Effekt als eine abgesetzte Pharmakotherapie aufweist.