A. Kästner

Increased Prevalence of Diverse N -Methyl-D-Aspartate Glutamate Receptor Antibodies in Patients With an Initial Diagnosis of Schizophrenia: Specific Relevance of IgG NR1a Antibodies for Distinction From N -Methyl-D-Aspartate Glutamate Receptor Encephalitis

CONTEXT Evidence for symptomatic convergence of schizophrenia and N-methyl-D-aspartate glutamate receptor (NMDA-R) encephalitis highlights the need for an assessment of antibody prevalence and specificity for distinct disease mechanisms in patients with a diagnosis of schizophrenia among glutamatergic pathophysiologic abnormalities in psychiatric disorders. OBJECTIVES To compare the specificity and prevalence of NMDA-R antibodies in schizophrenia (DSM-IV criteria) with those of other psychiatric diagnoses and to determine whether antibody subtypes characterize overlap with and distinction from those in NMDA-R encephalitis. DESIGN Serum from 459 patients admitted with acute schizophrenia, major depression (MD), and borderline personality disorder (BLPD) or individuals serving as matched controls was obtained from our scientific blood bank. To explore epitope specificity and antibody subtype, IgA/IgG/IgM NMDA-R (NR1a or NR1a/NR2b) and α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors (AMPA-R) (GluR1/GluR2) serum antibodies were determined. PARTICIPANTS Two hundred thirty matched healthy controls were compared with patients (unmedicated for at least 6 weeks) with schizophrenia (n = 121), MD (n = 70), or BLPD (n = 38). MAIN OUTCOME MEASURES The primary outcome was the overall number of seropositive cases for NMDA-R and AMPA-R antibodies; the secondary outcome was disease specificity of IgA/IgG/IgM antibodies and epitope specificity for clinical subgroups. RESULTS Diverse NMDA-R antibodies were identified in 15 subjects, primarily those with an initial schizophrenia diagnosis (9.9%), opposed to MD (2.8%), BLPD (0), and controls (0.4%). Retrospectively, 2 patients initially classified as having catatonic or disorganized schizophrenia were reclassified as having misdiagnosed NMDA-R encephalitis (presence of specific serum and cerebrospinal fluid IgG NR1a antibodies). In all other seropositive cases, the antibodies consisted of classes IgA and/or IgM or were directed against NR1a/NR2b (not against NR1a alone). None of the patients or controls had antibodies against AMPA-R. CONCLUSIONS Acutely ill patients with an initial schizophrenia diagnosis show an increased prevalence of NMDA-R antibodies. The repertoire of antibody subtypes in schizophrenia and MD is different from that with NMDA-R encephalitis. The latter disorder should be considered as a differential diagnosis, particularly in young females with acute disorganized behavior or catatonia.

Digital selenium radiography: detection of subtle pulmonary lesions on images acquired with and without an additional antiscatter grid

OBJECTIVE the objective of this ROC-study was to evaluate the diagnostic efficacy of images acquired with a grid in digital selenium radiography compared to that on images obtained with the integrated air gap only. MATERIALS AND METHODS seven types of simulated lesions were superimposed onto an anthropomorphic chest phantom. Selenium radiography images were obtained either with or without an additional antiscatter grid. For images acquired with a grid either a similar or increased exposure level was used. Both normal and obese patients were simulated. RESULTS When a grid was used with an equivalent detector dose and a higher exposure, diagnostic performance was significantly improved as compared to images obtained with only the air gap. ROC curve areas for mediastinal nodules and catheters were substantially higher for images acquired with a grid and the same exposure level compared to images obtained without a grid. However, detection of linear, net-shaped and reticulonodular structures in peripheral lung regions was significantly worse when a grid was used with an equivalent exposure level. Concerning the interpretation of images obtained from the normal and obese phantom models, no substantial differences were observed. CONCLUSION a marked improvement in diagnostic performance could be achieved by means of the use of an additional antiscatter grid and an equivalent detector dose. However, when the same exposure was used, images acquired with the grid allowed a better detection of mediastinal structures although a worse performance was evident in radiolucent lung regions. Therefore, the routine use of a grid without increased exposure is not recommended.

Neuroradiologische Befunde zur Beurteilung der Prognose bei Patienten nach Schädel-Hirn-Traumen

ZusammenfassungZiel: In der vorliegenden Untersuchung sollte die prognostische Wertigkeit von neuroradiologischen Befunden in der Computertomographie (CT) und der Magnetresonanztomographie (MRT) bei Patienten mit einem Schädel-Hirn-Trauma (SHT) in Bezug auf die Prognose verglichen werden. Patienten und Methoden: Untersucht wurden 100 Patienten nach einem SHT, die mindestens 24 Stunden bewusstlos waren. Es wurden die Komadauer und das Behandlungsergebnis mittels der Glasgow Outcome Scale (GOS) registriert. Ausgewertet wurden die primären zerebralen CT-Untersuchungen vom Unfalltag und MRT-Untersuchungen, die im Mittel 5 Tage nach dem SHT erfolgten. Ergebnisse: Die engsten Korrelationen zum GOS fanden sich mit − 0,711 (p = 0,01) für die Hirnstammläsionen im MRT. Im CT fanden sich geringe Korrelationen zum GOS für die Kontusion im Hirnstamm, die Hirnstammschwellung und die Einengung der infratentoriellen Zisternen. Die supratentoriellen Befunde in CT und MRT korrelierten bis auf die Einengung der basalen Zisternen nicht mit dem GOS. Schädelbasis- und Mittelgesichtsfrakturen zeigten eine geringe Korrelation zur MRT-Klassifikation der Hirnstammläsionen. Infratentorielle Befunde, Schädelbasisfrakturen und Mittelgesichtsfrakturen im CT können Hinweise auf eine Hirnstammläsion sein. Schlussfolgerungen: Prognostische Vorhersagen bei Patienten mit einem SHT sind mit ausreichender Sicherheit nur mit der MRT-Klassifikation der Hirnstammläsionen möglich. Bei Patienten mit diskrepanter Klinik (anhaltende posttraumatische Bewusstlosigkeit) und ohne intrakranielle Verletzungszeichen im CT sollte ein MRT erfolgen.AbstractObjective: In this study the predictive value of neuroradiological investigations using computed tomography (CT) and magnetic resonance imaging (MRI) on patients suffering from head injuries is compared. Patients and Methods: 100 patients comatose for at least 24 hours after head injury were included. Outcome was classified according to the Glascow Outcome Scale (GOS). CT scans were performed on the day of the accident and MRI on average 5 days after trauma. Results: The highest correlation with the GOS (– 0,711, p = 0,01) was found for brain stem lesions. Less significant correlations with the GOS were shown for CT scan results corresponding to infratentorial injuries such as contusion within the brain stem, swelling of the brain stem or any compression of the infratentorial cisterns. The supratentorial injuries seen on CT or MRI did not correlate with the GOS except for any compressions of the basal cisterns. A loose relation was identified between skull base or mid-facial fractures and the MRI classification of brain stem lesions. Results of the CT-scans corresponding to infratentorial injuries, skull base or mid-facial fractures may suggest possible brain stem lesions. Conclusions: GOS of patients with head injuries can only be predicted using MRI exams. In patients showing unclear findings (e.g., continuous coma after trauma) without any intracranial lesions in the CT scans, MRI should be performed.

Diffusion Tensor Imaging (DTI) in patients in a state of brain death

dynamic parameters were induced by regular breathing at a rate of 6/min. Basic results were that: (1) BP-induced cerebral microvascular oscillations (NIRS) follow those of macrovascular oscillations (MCAFV) with a certain phase of 80–90 (corresponding to 2–2.5 s at 0.1 Hz), most likely reflecting a transit time phenomenon; (2) oxyand deoxyhemoglobin thereby oscillate with a counterphase behaviour; (3) hemodynamic compromise in carotid obstruction leads to (a) delayed NIRS oscillations in comparison to BP which are highly correlated to a shorter phase lead of MCAFV against BP and (b) an uncoupling of the oxy-/deoxyhemoglobin counterphase to 240 . We conclude that also microvascular hemodynamic responses to BP oscillations follow specific phase relationships due to cerebral autoregulatory action and circulatory transit times. With hemodynamic impairment, as in unilateral carotid obstruction, these phases are significantly changed reflecting disturbed autoregulation.

Diffusions-Tensor-Bildgebung (DTI) bei Patienten im apallischen Syndrom

ZusammenfassungHintergrund und Ziel:Die Diagnostik des apallischen Syndroms beschränkte sich bisher auf die klinische Untersuchung und Zusatzuntersuchungen mittels EEG und evozierter Potentiale. Die Bildgebung spielte bei der Diagnosesicherung keine Rolle. Mit der Diffusions-Tensor-Bildgebung (DTI) sollte versucht werden, den Defektbereich im Hirnstamm zu visualisieren.Patienten und Methodik:Sieben Patienten im apallischen Syndrom nach Schädel-Hirn-Trauma (SHT) wurden in einem 1,5-Tesla-MRT-Gerät (INTERA, Fa. Philips) mit koronaren diffusionsgewichteten Spinechosequenzen untersucht. Es wurden sechs nicht kolineare Gradientenanregungen entlang den kortikospinalen Bahnsystemen verwendet. Die Untersuchung fand im Mittel 6 Monate nach SHT statt. Die Rekonstruktion der Faserbahnen erfolgte mit einem IDL-basierten (Interactive Data Language; Research System Inc.) Fiber-Tracking-Tool. Im Defektbereich wurden des weiteren der ADC („apparent diffusion coefficient“) und die FA (fraktionelle Anisotropie) bestimmt und mit einer Kontrollgruppe von 20 gesunden Probanden verglichen.Ergebnisse:Die Faserdarstellung zeigte bei allen Patienten eine Unterbrechung der kortikospinalen Bahnsysteme auf Höhe des Mesencephalons. Die ADC-Werte im Defektbereich waren im Vergleich zur Kontrollgruppe normal bis leicht erhöht. Die FA-Werte waren um fast 40% reduziert als Ausdruck einer Schädigung auf zellulärer Ebene. Patienten mit Kontrollen nach ≥ 5 Monaten zeigten atrophische Hirnstammveränderungen in Pons und Mesencephalon als morphologisches Korrelat einer Schädigung auf zellulärer Ebene.Schlussfolgerung:Mit Hilfe der DTI ist es erstmals gelungen, die Unterbrechung kortikospinaler Bahnsysteme bei apallischen Patienten zu visualisieren. Die FA-Werte können als Marker der Schädigung auf zellulärer Ebene angesehen werden und dürften für den Verlauf und die Verlaufsbeurteilung dieser Patientengruppe von Bedeutung sein.AbstractBackground and Purpose:So far, the diagnostics of persistent vegetative state has been limited to the clinical examination and auxiliary investigations by means of EEG and evoked potentials. Imaging techniques did not play a role in securing the diagnosis. Using diffusion tensor imaging (DTI), it was tried to visualize the defect area in the brain stem.Patients and Methods:Seven patients in a persistent vegetative state after cerebral trauma were examined in a 1.5-T MRI device (INTERA, Philips Co) with coronal diffusion-weighted spin echo sequences. Six non-colinear gradient impulses were used along the corticospinal fiber tracts. The investigation took place after a mean of 6 months following cerebral trauma. For reconstruction of the fibers’ courses, an IDL-based (Interactive Data Language; Research System Inc.) fiber tracking tool was used. Furthermore, ADC (apparent diffusion coefficient) and FA (fractional anisotropy) were determined in the defect area and compared with a control group of 20 healthy test persons.Results:The fiber representation showed an interruption of the corticospinal fiber tracts at the level of the mesencephalon in all patients. The ADC values in the defect area were normal to slightly increased as compared to the control group. The FA values were reduced by nearly 40%, indicating a damage on the cellular level. Patients undergoing controls after ≥ 5 months showed atrophic brain stem changes in the pons and mesencephalon due to morphological correlate of a damage on the cellular level.Conclusion:With the help of DTI, the interruption of corticospinal fiber tracts could first be visualized in patients with persistent vegetative state. The FA values can be regarded as markers of the damage on the cellular level and might be important for the course of disease and its evaluation in this patient group.