Bernhard Kis

Preoperative embolization of intracranial arteriovenous malformations with Onyx.

OBJECTIVE Preoperative embolization in accordance with multimodal therapies for cerebral arteriovenous malformations (AVMs) is generally the first step in treatment and may result in complete obliteration. The Onyx liquid embolic system (Micro Therapeutics, Inc., Irvine, CA) may offer advantages for intranidal targeted embolization and microsurgical resection. We present our experience in the combined treatment of intracranial AVMs using Onyx embolization and neurosurgical resection. METHODS We treated a total of 47 patients for compact intracranial AVMs that were located in the frontal or frontoparietal area (16 patients); temporal, temporoparietal, or temporo-occipital regions (12 patients); parietal or parieto-occipital areas (8 patients); occipital regions (8 patients); had basal ganglia involvement (2 patients); and was cerebellar (1 patient). The Spetzler-Martin grading scale values were as follows: 25 patients were Grades I or II, 10 patients were Grade III, and 12 patients were Grades IV or V. Twenty-three AVMs were located in eloquent brain regions. RESULTS After we performed final embolizations, the mean nidus reduction was 84%. Seven patients had new, nondisabling neurological deficits, and four patients had new, disabling neurological deficits after embolization. Periprocedurally, five vessel perforations and four stuck microcatheters were encountered without clinical deficits. In two patients, delayed hemorrhage after embolization occurred with good clinical outcome. We completely resected 46 AVMs; in one patient, we detected an AVM on postoperative angiography. The mean operative time was 4.7 hours, and the mean blood loss was 455 mL. Clinical status worsened postoperatively in 14 patients. Angiographic and clinical follow-up examinations were available for 42 patients (89%); the average follow-up period was 13 months. We found no relapse of arteriovenous shunt. Fourteen patients improved clinically after discharge. Of the 42 patients followed up, 23 individuals had no neurological deficit, 16 had a nondisabling deficit, and three had a disabling deficit. CONCLUSION Preoperative use of the Onyx liquid embolic system in cerebral AVM treatment allows profound occlusion by targeted embolization and provides a basis for safe neurosurgical resection.

ELECTIVE TREATMENT OF SACCULAR AND BROAD-NECKED INTRACRANIAL ANEURYSMS USING A CLOSED-CELL NITINOL STENT (LEO)

OBJECTIVE: Endovascular coil embolization of saccular intracranial aneurysms is safe and effective, but long-term results are dissatisfying. Reconstructive treatments using stents improve occlusion rate and protect parent vessels. We present data on our experience with a new self-expanding stent manufactured with braided nitinol wires. METHODS: Twenty-five saccular, complex, and broad-necked intracranial aneurysms in 21 patients were treated electively. They were located at the internal carotid artery (10), basilar trunk (5), cavernous carotid artery (4), basilar tip (2), anterior cerebral artery (2), anterior communicating artery (1), and middle cerebral artery (1). Eleven aneurysms exhibited recanalization after primary endovascular treatment without stent. RESULTS: Stent deployment was successful in 24 lesions, and additional coil embolization was performed in 23. No permanent neurological deficits were encountered consequent to endovascular procedure. Complete or partial occlusion immediately after stent deployment was achieved in 19 aneurysms, whereas no immediate coil embolization was chosen in 6 cases. There were two thromboembolic events related to the deployment of the Leo stent, one failure of stent deployment, difficulties in stent positioning in three cases, and one asymptomatic parent artery occlusion after 7 months. Follow-up (available in 18 patients and 21 aneurysms and obtained at 3–12 mo; average, 5 mo) revealed patent stents in the remaining cases. Angiographic recurrences arose in three lesions, which were retreated without complications. CONCLUSION: Primary and recurrence treatment of saccular and broad-necked intracranial aneurysms using the Leo stent is feasible and effective. No permanent neurological deficits were associated with stent placement. Short-term follow-up identified intact parent arteries and stable occlusion rates in the majority of cases.

Clinical characteristics of patients with late-onset multiple sclerosis.

We evaluated clinical presentation, cerebrospinal fluid (CSF), and magnetic resonance imaging (MRI) in patients with late-onset multiple sclerosis (LOMS). Fifty-two patients with definitive multiple sclerosis (MS) diagnosed after the age of 50 years were identified between 1991 and 2002. Data pertaining to clinical characteristics, CSF analysis, and cerebral and spinal MRI were compared with those of 52 young-onset MS (YOMS) patients matched for sex and disease duration. Mean age at the time of diagnosis was 57 years in the LOMS group – the oldest patient was 82 – and 29 years in the YOMS group. Motor symptoms were significantly more often present in the LOMS than in patients with YOMS (90 % vs. 67 %, p = 0.014). Visual symptoms, residual signs of optic neuritis, and dysarthria were less frequent for LOMS. Sensory symptoms, ataxia, oculomotor symptoms, cognitive disorder, or fatigue did not differ between both groups. The majority of LOMS patients (83 %) had a primary progressive disease course, whereas 94 % of the YOMS group had a relapsing-remitting course. MRI showed typical multifocal supratentorial (LOMS vs. YOMS: 96 % vs. 98 %) and infratentorial (44 % vs. 62 %) lesions without significant group differences. Of particular interest, spinal lesions were more common (81 %) in LOMS compared to YOMS (48 %, p = 0.024), and cerebellar lesions were less frequent in the LOMS group (11 % vs. 44 %, p = 0.001). Gadolinium-enhanced lesions were initially present in less LOMS patients (15 %) than in YOMS (63 %, p < 0.001). CSF analysis revealed pleocytosis less frequently in LOMS (34 %) compared to YOMS (67 %, p = 0.006) but oligoclonal banding occurred without in both groups without differences. YOMS patients responded to corticosteroids (93 %) to a significantly greater degree than LOMS patients (73 %; p = 0.004). For individuals who develop LOMS, a primary progressive course is frequent, with motor symptoms as the prominent feature. Vigilance is necessary to recognise MS in this population because of its unusual presentation.

German validation of the Conners Adult ADHD Rating Scales-self-report (CAARS-S) I: factor structure and normative data.

BACKGROUND Attention-deficit/hyperactivity disorder (ADHD) often persists into adulthood. Instruments for diagnosing ADHD in childhood are well validated and reliable, but diagnosis of ADHD in adults remains problematic. Attempts have been made to develop criteria specific for adult ADHD, resulting in the development of self-report and observer-rated questionnaires. To date, the Conners Adult ADHD Rating Scales (CAARS) are the international standard for questionnaire assessment of ADHD. The current study evaluates a German version of the CAARS self-report (CAARS-S). METHODS Eight hundred and fifty healthy German control subjects were recruited to fill out the CAARS-S and to answer questions on sociodemographic variables. Explorative and confirmative factor analyses were conducted to obtain the factor structure for the German model and to replicate the factor structure of the original American model. Analyses on gender, age, and education level were calculated for normative data. RESULTS The explorative factor analysis of the German sample results in a six-factor solution that explained 52% of the variance. A confirmative analysis that was based on the 42 items of the original American model showed a high model-fit. Analyses of normative data showed significant influences of age, gender, and education level on the emerging subscales. CONCLUSION Even though the explorative factor analysis yields a solution different from the American original, the confirmative factor analysis results in such a high model-fit that use of the American version is justified with respect to international multicenter studies, for which this instrument will be highly valuable.

The impact of acute tryptophan depletion on attentional performance in adult patients with ADHD.

To date, the impact of the neurotransmitter serotonin (5‐HT) on different neuropsychological functions in adults with attention deficit hyperactivity disorder (ADHD) is underinvestigated. We aimed to examine the effects of acute tryptophan depletion (ATD) and the resulting reduction in central nervous 5‐HT synthesis on target/non‐target discrimination ability and sustained attention in adults with ADHD using an AX‐Continuous Performance Test (AX‐CPT).

Methylphenidate-induced psychosis in adult attention-deficit/hyperactivity disorder: report of 3 new cases and review of the literature.

Objective:We present 3 new cases of psychotic symptoms in patients with adult attention-deficit/hyperactivity disorder while regularly treated with a stimulant therapy with methylphenidate. Methods:Existing literature about this theme is reviewed, and potential mechanisms are discussed. Results and Conclusions:Medication with methylphenidate should be avoided in patients with vulnerability to schizophrenia and in drug addiction, but reported cases without these risk factors demonstrate that a careful and regular psychiatric monitoring is essential in all patients treated with methylphenidate.

The Effects of Acute Tryptophan Depletion on Reactive Aggression in Adults with Attention-Deficit/Hyperactivity Disorder (ADHD) and Healthy Controls

Background The neurotransmitter serotonin (5-HT) has been linked to the underlying neurobiology of aggressive behavior, particularly with evidence from studies in animals and humans. However, the underlying neurobiology of aggression remains unclear in the context of attention-deficit/hyperactivity disorder (ADHD), a disorder known to be associated with aggression and impulsivity. We investigated the effects of acute tryptophan depletion (ATD), and the resulting diminished central nervous serotonergic neurotransmission, on reactive aggression in healthy controls and adults with ADHD. Methodology/Principal Findings Twenty male patients with ADHD and twenty healthy male controls were subjected to ATD with an amino acid (AA) beverage that lacked tryptophan (TRP, the physiological precursor of 5-HT) and a TRP-balanced AA beverage (BAL) in a double-blind, within-subject crossover-study over two study days. We assessed reactive aggression 3.25 hours after ATD/BAL intake using a point-subtraction aggression game (PSAG) in which participants played for points against a fictitious opponent. Point subtraction was taken as a measure for reactive aggression. Lowered rates of reactive aggression were found in the ADHD group under ATD after low provocation (LP), with controls showing the opposite effect. In patients with ADHD, trait-impulsivity was negatively correlated with the ATD effect on reactive aggression after LP. Statistical power was limited due to large standard deviations observed in the data on point subtraction, which may limit the use of this particular paradigm in adults with ADHD. Conclusions/Significance Together with previous findings, the data provide preliminary evidence of an inverse association between trait-impulsivity and the ATD effect on reactive aggression after LP (as assessed by the PSAG) in patients with ADHD and that this relationship can be found in both adolescents and adults. Because of limited statistical power larger sample sizes are needed to find main effects of ATD/BAL administration on reactive aggression in adults with ADHD.

German Validation of the Conners Adult ADHD Rating Scale–Self-Report: Confirmation of Factor Structure in a Large Sample of Participants with ADHD

Objective: The Conners Adult ADHD Rating Scales (CAARS) assess symptoms specific to adults that are frequently used and have been translated into German. The current study tests the factor structure of the CAARS in a large sample of German adults with ADHD and compares the means of the CAARS subscales with those of healthy German controls. Method: CAARS were completed by 466 participants with ADHD and 851 healthy control participants. Confirmatory factor analysis was used to establish model fit with the American original. Comparisons between participants with ADHD and healthy controls and influences of gender, age, and degree of education were analyzed. Results: Confirmatory factor analysis showed a very good fit with the model for the American original. Differences between ADHD participants and healthy controls on all Conners Adult ADHD Rating Scales–Self-Report (CAARS-S) subscales were substantial and significant. Conclusion: The factor structure of the original American model was successfully replicated in this sample of adult German ADHD participants.

A pilot clinical trial of oxcarbazepine in adults with attention-deficit hyperactivity disorder

Despite the increasing recognition of attention-deficit hyperactivity disorder (ADHD) in adults, there is a paucity of controlled pharmacological trials. Recent reports have suggested the potential usefulness of mood stabilizing drugs for ADHD. To this end, the authors completed a pilot study with oxcarbazepine for the treatment of adults with ADHD. This was an open pilot study of oxcarbazepine (300-1,500 mg daily dosage) in adults who met DSM-IV criteria for ADHD. The treatment period was 8 weeks. Of the 9 subjects enrolled in the study (4 men, 5 women), 8 patients could be included in the analysis. At the endpoint of the active treatment, a significantly high proportion of subjects was considered improved while receiving oxcarbazepine. ADHD symptom checklist scores (ADHD-IV rating scale, Conners ADHD adult rating scale, ADHD self-rating [ADHD-SR] scale) showed significant reduction during the treatment period. Treatment with oxcarbazepine was relatively well tolerated; dizziness, sedation and nausea were the most frequently reported adverse effects. The results of this investigation indicate that oxcarbazepine may be a potentially useful agent for the treatment of ADHD in adults. However, placebo-controlled randomized trials are needed to provide evidence.

No clear effects of acute tryptophan depletion on processing affective prosody in male adults with ADHD

Adults with attention deficit hyperactivity disorder (ADHD) have difficulties processing affective prosody, and research evidence demonstrates the importance of brain serotonin (5‐HT) in the neurobiology of ADHD. This study aimed to investigate whether diminished brain 5‐HT synthesis, as achieved by acute tryptophan depletion (ATD), can impair the processing of affective prosody in adults with ADHD.