Classification of obsessive-compulsive disorder in childhood and adolescence.

OBJECTIVE: In child and adolescent psychiatry the validation of the diagnosis must be seen in the context of development. Comparing different diagnostic formulations DSM-IV and ICD-10-DCR in a clinical sample of children and adolescents suffering from obsessive-compulsive disorder (OCD) and their validation on external criteria represent such a heuristic approach. METHOD: We investigated 61 children seen consecutively in a specialized out-patient clinic for OCD. All of them were assessed by the International Diagnostic Checklists (IDCL). Diagnosis and diagnostic certainty were validated regarding age, age of onset and duration of illness. RESULTS: The agreement between the two diagnostic systems was low. The diagnostic stability of ICD-10-DCR was highly dependent on age, whereas that of the criteria DSM-IV did not depend on age and almost all subjects could be diagnosed definitely. CONCLUSION: This study suggests that the DSM-IV criteria are superior to that of ICD-10-DCR for diagnosing OCD in children and younger adolescents.

Nonlinear dynamics of 3 Hz spike-and-wave discharges recorded during typical absence seizures in children.

One-channel routine recordings of the scalp electroencephalogram (EEG) from unmedicated children strictly classified as unprovoked typical (3 c/s) absence seizures were selected. The dynamics of spike-and-wave discharges (SWD) were then examined by means of autocorrelation, correlation dimension, averaged pointwise dimension and largest Lyapunov exponent. For one EEG signal with pronounced spike-and-wave (SW) patterns, these measures were used complementary to a surrogate data method, a nonlinear (SETAR) modeling approach, and a SW simulation procedure providing five types of SW test signals. The SETAR model exhibited stationary SW dynamics, visually very similar to the EEG target signal, and with clear nonlinear structure. According to the results, the EEG episodes investigated represent low-dimensional dynamics, possibly recorded during nonstationary periods. Arguments that justify the assumption of deterministic chaos in our EEG signals were not obtained with the current methods. From the results one may conclude that two global oscillatory modes are present for the model, and three modes are active during the EEG recording period.

Simultaneous spike detection and topographic classification in pediatric surface EEGs.

In this study, an algorithm is introduced for the automatic detection and simultaneous topographic classification of interictal regional spike activity in pediatric surface EEG records. The algorithm is based on the classification of the topographic distribution of instantaneous power by means of a 'group' trained classifier. The results of automatic spike analysis were compared with the decisions of two experienced electroencephalographers. Four routine EEG records exhibiting (multi)regional spikes were examined. The mean selectivity for the automatic spike detector was 84.6% (mean sensitivity 88.1%, mean specificity 89.3%) and for the electroencephalographers 85.3%. All spikes detected by the algorithm were simultaneously classified according to their topographic characteristics. The results of automatic spike classification (lateralization/localization) corresponded to the results of visual analysis.

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.

Is there a pathophysiological and therapeutic link between panic disorder and epilepsy?

Relations between panic disorder (PD) and epilepsy (E) have repeatedly been discussed. Three patients with juvenile E who had been free of seizures under anticonvulsant medication for many years and developed PD are presented. Increasing anticonvulsant medication resulted in complete and stable remission of PD. It is hypothesized that, in a subgroup of patients with PD, there is a pathophysiological relation to E. Further research into the usefulness of anticonvulsants in the treatment of PD, especially in therapy-refractory cases, is suggested.

EEG-brain mapping in schizophrenics with predominantly positive and negative symptoms. Comparative studies with remoxipride/haloperidol.

EEG brain maps obtained in 48 drug-free hospitalized schizophrenics diagnosed according to DSMIII demonstrated significant differences as compared with normal controls characterized by a decrease of alpha-1 activity, increase of beta activity and acceleration of the centroid. These findings suggest a state of sustained hyperarousal in schizophrenia. While the patients with negative schizophrenia showed a bi-temporal and frontal augmentation of delta/theta activity, patients with florid symptomatology exhibited just the opposite findings. Alpha-1 activity was attenuated, beta activity augmented in both groups with the findings more pronounced in the positive schizophrenia group. The increase of slow activity suggests an organic factor in the pathogenesis of the negative syndrome, which was supported by correlation maps between EEG measures and the apathy syndrome as measured by the AMDP system. Treatment of schizophrenics with predominantly positive symptoms with 2 different neuroleptics such as remoxipride and haloperidol resulted also in differential effects on brain activity: while haloperidol augmented delta/theta and alpha activity and decreased beta activity, remoxipride produced a decrease of slow and increase of beta activity as well as an acceleration of the centroid suggesting vigilance-promoting properties of the drug. These differential effects on the neurophysiological level were also reflected at the behavioural one evaluated by psychometry, while global clinical evaluation showed, as expected, similar improvement with both drugs (apart from extrapyramidal side effects being significantly more pronounced after haloperidol than remoxipride). Our findings suggest that brain electrical signal topography is a promising method in regard to a better understanding of pathogenesis and treatment in schizophrenia.

Smooth pursuit eye movements in schizophrenia: influences of neuroleptic treatment and the question of specificity.

The authors investigated smooth pursuit eye movements (SPEMs) in 66 schizophrenic and 40 major affective patients and 39 healthy controls. The results showed significant differences of both patient groups as compared to the controls. Schizophrenics with neuroleptic treatment in the preceding 2 years were significantly more disturbed than the controls, the affective patients and the untreated schizophrenics. Acute neuroleptic medication and neuroleptic treatment of a duration of 4-6 weeks appear not to significantly influence the quality of SPEMs.