Markus Kraemer

Moyamoya Disease in Europeans

Background and Purpose— We describe the clinical, diagnostic, and outcome features of a cohort of white patients with idiopathic moyamoya disease treated in a German institution. Methods— Our cohort included 21 white patients with moyamoya disease. Clinical and diagnostic features were obtained by retrospective chart review; follow-up information and outcome were obtained prospectively. We used the Kaplan–Meier methods to estimate stroke risk by treatment status. Results— The mean age at onset of symptoms was 31 years. The female predominance was 4.25:1. In our cohort, the initial symptom was a cerebral ischemic event in all patients. There was no patient with a hemorrhage at onset; only one patient experienced subarachnoidal hemorrhage in the further course of disease. The Kaplan–Meier risk for recurrent stroke was very high after the first ischemic event and smaller after angiographic diagnosis. The 5-year-Kaplan–Meier risk of recurrent stroke was 80.95% after the first ischemic event for all patients. Most subsequent ischemic events appeared in the first 2 years after symptom onset. Eleven patients (52.3%) underwent neurosurgical revascularizing procedures. After surgery, the Kaplan–Meier risk of perioperative or subsequent stroke was 27.27% within the first month and was stable thereafter. Conclusion— Clinical features and course of moyamoya disease of whites analyzed in this German study are comparable to American results. Moyamoya disease in whites differs clearly from Asian moyamoya disease in timing of onset of vasculopathy and lower rate of hemorrhages.

Diagnostic problems and delay of diagnosis in amyotrophic lateral sclerosis

OBJECTIVE Initial symptoms of amyotrophic lateral sclerosis (ALS) mimic several neurological syndromes that may decelerate a correct diagnosis. The aim of our study was to investigate if diagnostic and therapeutic parameters have influence on the time of diagnosis. METHODS We retrospectively reviewed the medical records of 100 consecutive ALS patients focusing on clinical and diagnostic data, the timing of diagnosis and treatments attributed to the onset of symptoms of ALS. RESULTS Among 100 consecutive patients with ALS, 12% underwent surgery due to symptoms retrospectively attributable to ALS. The comparison of duration from first symptoms to correct diagnosis showed a significant difference between operated and non-operated patients. 35% of all ALS patients had bulbar onset symptoms. The mean time from first symptoms to diagnosis was 9 months in this group. In patients without bulbar onset it was 16.4 months which also represents a significant difference. In 44% of patients other diagnoses were considered and medically treated previous to correct diagnosis, but there was no significant delay of diagnosis. CONCLUSION Our study confirms that diagnosis of ALS is still a common clinical problem and shows the need of sensitive and specific diagnostic tests.

The spectrum of differential diagnosis in neurological patients with livedo reticularis and livedo racemosa. A literature review.

AbstractLivedo is a cutaneous sign of striking violaceous netlike patterned erythema of the skin. This dermatological phenomenon is of special interest in the differential diagnosis in neurological patients. In 1907 Ehrmann distinguished two different patterns of livedo: the pathological livedo racemosa and the physiological livedo reticularis. Despite important clinical differences, in the English language literature the heading livedo reticularis is still used for all types of livedo. A literature review about the spectrum of differential diagnosis in patients with livedo reticularis (especially cutis marmorata and amantadine–induced livedo reticularis) and livedo racemosa (especially Sneddon’s syndrome, Divry–van Bogaert syndrome, systemic lupus erythematosus, antiphospholipid antibody syndrome, polyarteritis nodosa, cholesterol embolization syndrome, livedoid vasculopathy and haematological diseases) is provided.

The spectrum of differential diagnosis in neurological patients with livedo reticularis and livedo racemosa

AbstractLivedo is a cutaneous sign of striking violaceous netlike patterned erythema of the skin. This dermatological phenomenon is of special interest in the differential diagnosis in neurological patients. In 1907 Ehrmann distinguished two different patterns of livedo: the pathological livedo racemosa and the physiological livedo reticularis. Despite important clinical differences, in the English language literature the heading livedo reticularis is still used for all types of livedo. A literature review about the spectrum of differential diagnosis in patients with livedo reticularis (especially cutis marmorata and amantadine–induced livedo reticularis) and livedo racemosa (especially Sneddon’s syndrome, Divry–van Bogaert syndrome, systemic lupus erythematosus, antiphospholipid antibody syndrome, polyarteritis nodosa, cholesterol embolization syndrome, livedoid vasculopathy and haematological diseases) is provided.

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.

Cerebral vasculitis in adults: what are the steps in order to establish the diagnosis? Red flags and pitfalls

Cerebral vasculitis is a rare cause of juvenile stroke. It may occur as primary angiitis of the central nervous system (PACNS) or as CNS manifestation in the setting of systemic vasculitis. Clinical hints for vasculitis are headache, stroke, seizures, encephalopathy and signs of a systemic inflammatory disorder. Diagnostic work‐up includes anamnesis, whole body examination, laboratory and cerebral spinal fluid (CSF) studies, magnetic resonance imaging (MRI), angiography and brain biopsy. Due to the rarity of the disease, exclusion of more frequent differential diagnoses is a key element of diagnostic work ‐up. This review summarizes the steps that lead to the diagnosis of cerebral vasculitis and describes the red flags and pitfalls. Despite considering the dilemma of angiography‐negative vasculitis and false‐negative brain biopsy in some cases, it is important to protect patients from ‘blind’ immunosuppressive therapy in unrecognized non‐inflammatory differential diagnosis.

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.

Visual evoked potentials in neuromyelitis optica and its spectrum disorders.

Optic neuritis (ON) is a key feature of neuromyelitis optica (NMO). Recently, NMO patients of predominantly Afro-Brazilian origin were evaluated by visual evoked potentials (VEPs) and showed marked amplitude reductions. Here, we analyzed VEPs in a predominantly Caucasian cohort, consisting of 43 patients with definite NMO, 18 with anti-aquaporin (AQP) 4 antibody-seropositive NMO spectrum disorders and 61 matched healthy controls. We found reduced amplitudes in only 12.3%, prolonged latencies in 41.9% and a lack of response in 14.0% of NMO eyes. Delayed P100 latencies in eyes without prior ON suggested this was a subclinical affection. The data indicate heterogenous patterns in NMO, warranting further investigation.

Improved cerebral time-of-flight magnetic resonance angiography at 7 Tesla--feasibility study and preliminary results using optimized venous saturation pulses.

Purpose Conventional saturation pulses cannot be used for 7 Tesla ultra-high-resolution time-of-flight magnetic resonance angiography (TOF MRA) due to specific absorption rate (SAR) limitations. We overcome these limitations by utilizing low flip angle, variable rate selective excitation (VERSE) algorithm saturation pulses. Material and Methods Twenty-five neurosurgical patients (male n = 8, female n = 17; average age 49.64 years; range 26–70 years) with different intracranial vascular pathologies were enrolled in this trial. All patients were examined with a 7 Tesla (Magnetom 7 T, Siemens) whole body scanner system utilizing a dedicated 32-channel head coil. For venous saturation pulses a 35° flip angle was applied. Two neuroradiologists evaluated the delineation of arterial vessels in the Circle of Willis, delineation of vascular pathologies, presence of artifacts, vessel-tissue contrast and overall image quality of TOF MRA scans in consensus on a five-point scale. Normalized signal intensities in the confluence of venous sinuses, M1 segment of left middle cerebral artery and adjacent gray matter were measured and vessel-tissue contrasts were calculated. Results Ratings for the majority of patients ranged between good and excellent for most of the evaluated features. Venous saturation was sufficient for all cases with minor artifacts in arteriovenous malformations and arteriovenous fistulas. Quantitative signal intensity measurements showed high vessel-tissue contrast for confluence of venous sinuses, M1 segment of left middle cerebral artery and adjacent gray matter. Conclusion The use of novel low flip angle VERSE algorithm pulses for saturation of venous vessels can overcome SAR limitations in 7 Tesla ultra-high-resolution TOF MRA. Our protocol is suitable for clinical application with excellent image quality for delineation of various intracranial vascular pathologies.