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Featured researches published by Jens Harmel.


Multiple Sclerosis Journal | 2013

Retinal ganglion cell and inner plexiform layer thinning in clinically isolated syndrome

Timm Oberwahrenbrock; Marius Ringelstein; Simon Jentschke; Katrin Deuschle; Katharina Klumbies; Judith Bellmann-Strobl; Jens Harmel; Klemens Ruprecht; Sven Schippling; Hans-Peter Hartung; Orhan Aktas; Alexander U. Brandt; Friedemann Paul

Background: Axonal and neuronal damage are widely accepted as key events in the disease course of multiple sclerosis. However, it has been unclear to date at which stage in disease evolution neurodegeneration begins and whether neuronal damage can occur even in the absence of acute inflammatory attacks. Objective: To characterize inner retinal layer changes in patients with clinically isolated syndrome (CIS). Method: 45 patients with CIS and age- and sex-matched healthy controls were investigated using spectral domain optical coherence tomography. Patients’ eyes were stratified into the following categories according to history of optic neuritis (ON): eyes with clinically-diagnosed ON (CIS-ON), eyes with suspected subclinical ON (CIS-SON) as indicated by a visual evoked potential latency of >115ms and eyes unaffected by ON (CIS-NON). Results: CIS-NON eyes showed significant reduction of ganglion cell- and inner plexiform layer and a topography similar to that of CIS-ON eyes. Seven eyes were characterized as CIS-SON and likewise showed significant retinal layer thinning. The most pronounced thinning was present in CIS-ON eyes. Conclusion: Our findings indicate that retinal pathology does occur already in CIS. Intraretinal layer segmentation may be an easily applicable, non-invasive method for early detection of retinal pathology in patients unaffected by ON.


Multiple Sclerosis International | 2012

Retinal Damage in Multiple Sclerosis Disease Subtypes Measured by High-Resolution Optical Coherence Tomography

Timm Oberwahrenbrock; Sven Schippling; Marius Ringelstein; Falko Kaufhold; Hanna Zimmermann; Nazmiye Keser; Kim Lea Young; Jens Harmel; Hans-Peter Hartung; Roland Martin; Friedemann Paul; Orhan Aktas; Alexander U. Brandt

Background. Optical coherence tomography (OCT) has facilitated characterisation of retinal alterations in MS patients. Only scarce and in part conflicting data exists on different MS subtypes. Objective. To analyse patterns of retinal changes in different subtypes of MS with latest spectral-domain technology. Methods. In a three-centre cross-sectional study 414 MS patients and 94 healthy controls underwent spectral-domain OCT examination. Results. Eyes of MS patients without a previous optic neuritis showed a significant reduction of both retinal nerve fibre layer (RNFL) thickness and total macular volume (TMV) compared to healthy controls independent of the MS subtype (P < 0.001 for all subtypes). RNFL thickness was lower in secondary progressive MS (SPMS) eyes compared to relapsing-remitting MS (RRMS) eyes (P = 0.007), and TMV was reduced in SPMS and primary progressive MS (PPMS) eyes compared to RRMS eyes (SPMS: P = 0.039, PPMS: P = 0.005). Independent of the subtype a more pronounced RNFL thinning and TMV reduction were found in eyes with a previous optic neuritis compared to unaffected eyes. Conclusion. Analysis of this large-scale cross-sectional dataset of MS patients studied with spectral-domain OCT confirmed and allows to generalize previous findings. Furthermore it carves out distinct patterns in different MS subtypes.


JAMA Neurology | 2015

Long-term Therapy With Interleukin 6 Receptor Blockade in Highly Active Neuromyelitis Optica Spectrum Disorder

Marius Ringelstein; Ilya Ayzenberg; Jens Harmel; Ann-Sophie Lauenstein; Eckart Lensch; Florian Stögbauer; Kerstin Hellwig; Gisa Ellrichmann; Mark Stettner; Andrew T. Chan; Hans-Peter Hartung; Bernd C. Kieseier; Ralf Gold; Orhan Aktas; Ingo Kleiter

IMPORTANCE Neuromyelitis optica (NMO) is characterized by disabling relapses of optic neuritis and myelitis and the presence of aquaporin 4 antibodies (AQP4-abs). Interleukin 6, which is significantly elevated in serum and cerebrospinal fluid of patients with NMO, induces AQP4-ab production by plasmablasts and represents a novel therapeutic target. OBJECTIVE To evaluate the long-term safety and efficacy of tocilizumab, a humanized antibody targeting the interleukin 6 receptor, in NMO and NMO spectrum disorder. DESIGN, SETTING, AND PARTICIPANTS Retrospective observational study with 10 to 51 months of follow-up between December 2010 and February 2015, in neurology departments at tertiary referral centers. Participants were 8 female patients of white race/ethnicity with highly active AQP4-ab-seropositive NMO (n = 6) and NMO spectrum disorder (n = 2) whose disease had been resistant to previous medications, including B-cell depletion, and who switched to tocilizumab (6-8 mg/kg of body weight per dose). MAIN OUTCOMES AND MEASURES Annualized relapse rate, Expanded Disability Status Scale score, spinal cord and brain magnetic resonance imaging, AQP4-ab titers, pain levels (numerical rating scale), and adverse effects. RESULTS Patients were followed up for a mean (SD) of 30.9 (15.9) months after switching to tocilizumab. Two of eight patients received add-on therapy with monthly corticosteroid pulses (temporary) or azathioprine, respectively. During tocilizumab treatment, the median annualized relapse rate significantly decreased from 4.0 (interquartile range, 3.0-5.0) in the year before tocilizumab therapy to 0.4 (interquartile range, 0.0-0.8) (P = .008), and the median Expanded Disability Status Scale score significantly decreased from 7.3 (interquartile range, 5.4-8.4) to 5.5 (interquartile range, 2.6-6.5) (P = .03). Active magnetic resonance imaging lesions were seen in 6 of 8 patients at tocilizumab initiation and in 1 of 8 patients at the last magnetic resonance imaging. Three patients remained relapse free during tocilizumab treatment. In 5 patients, a total of 8 relapses occurred, 4 within the first 2½ months of therapy. Five attacks were associated with delayed tocilizumab administration (≥40 days), and 6 attacks were associated with reduced tocilizumab dosage (6 vs 8 mg/kg). The AQP4-ab titers (P = .02) and pain levels (P = .02) dropped significantly during tocilizumab treatment. Adverse effects included moderate cholesterol elevation in 6 of 8 patients, infections in 4 of 8 patients, and deep venous thrombosis and neutropenia in one patient each. CONCLUSIONS AND RELEVANCE Prolonged tocilizumab therapy may be safe and effective from early treatment phases onward for otherwise therapy-resistant highly active NMO and NMO spectrum disorder. Relapse patterns indicate that adherence to a regular therapeutic regimen with monthly infusions of tocilizumab (8 mg/kg) may increase efficacy.


Multiple Sclerosis Journal | 2013

Neuromyelitis optica and pregnancy during therapeutic B cell depletion: infant exposure to anti-AQP4 antibody and prevention of rebound relapses with low-dose rituximab postpartum

Marius Ringelstein; Jens Harmel; Distelmaier F; Jens Ingwersen; Til Menge; Kerstin Hellwig; Bernd C. Kieseier; Mayatepek E; H.-P. Hartung; Tania Kuempfel; Orhan Aktas

Neuromyelitis optica (NMO) predominantly affects women, some in childbearing age, and requires early therapeutic intervention to prevent disabling relapses. We report an anti-AQP4 antibody-seropositive patient who became pregnant seven months after low-dose (100 mg) rituximab application. Pregnancy showed no complications, and low-dose rituximab restarted two days after delivery resulted in neurological stability for 24 months. Remarkably, her otherwise healthy newborn presented with anti-AQP4 antibody and reduced B lymphocyte counts in umbilical cord blood, which normalized three months later. Confirming and extending previous reports, our case suggests that low-dose rituximab might be compatible with pregnancy and prevent rebound NMO disease activity postpartum.


Neurology | 2015

Retinal pathology in Susac syndrome detected by spectral-domain optical coherence tomography

Marius Ringelstein; Philipp Albrecht; Ilka Kleffner; Björn Bühn; Jens Harmel; Ann-Kristin Müller; David Finis; Rainer Guthoff; Richard Bergholz; Thomas Duning; Markus Krämer; Friedemann Paul; Alexander U. Brandt; Timm Oberwahrenbrock; Janine Mikolajczak; Brigitte Wildemann; Sven Jarius; Hans-Peter Hartung; Orhan Aktas; Jan Dörr

Objective: The aim of this non-interventional study was to characterize retinal layer pathology in Susac syndrome (SuS), a disease with presumably autoimmune-mediated microvessel occlusions in the retina, brain, and inner ear, in comparison to the most important differential diagnosis multiple sclerosis (MS). Methods: Seventeen patients with SuS and 17 age- and sex-matched patients with relapsing-remitting MS (RRMS) and healthy controls (HC) were prospectively investigated by spectral-domain optical coherence tomography (OCT) including intraretinal layer segmentation in a multicenter study. Patients with SuS additionally received retinal fluorescein angiography (FA) and automated perimetry. Results: Patchy thinning of the retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, and outer plexiform layer compared to corresponding sectors in RRMS and HC eyes (p < 0.003 for SuS vs RRMS and HC) was observed in 23/34 (68%) SuS eyes, particularly in temporal quadrants. The outer nuclear layer (ONL) and photoreceptor layers (PRL) were not affected. FA performed in 15/17 patients with SuS was negative for disease-specific branch retinal artery occlusions in all but 1 eye at the time of OCT examination and revealed no additional vascular abnormalities, even in severely damaged OCT areas. In a subset of patients with SuS, associations of visual field data with distinct retinal layers were observed. Conclusion: Distinct OCT patterns of scattered, scar-like intraretinal pathology in SuS eyes, sparing the ONL and PRL, suggest a retinal, but not choroidal, vascular pathomechanism and clearly differentiate SuS from RRMS. Depending on the disease stage, OCT and FA provide specific complementary diagnostic information in SuS.


Annals of clinical and translational neurology | 2014

Subtle retinal pathology in amyotrophic lateral sclerosis

Marius Ringelstein; Philipp Albrecht; Martin Südmeyer; Jens Harmel; Ann-Kristin Müller; Nazmiye Keser; David Finis; Stefano Ferrea; Rainer Guthoff; Alfons Schnitzler; Hans-Peter Hartung; Axel Methner; Orhan Aktas

Amyotrophic lateral sclerosis (ALS) is characterized by neuro‐ophthalmological abnormalities beyond disturbed oculomotor control such as decreased visual acuity and disturbed visual evoked potentials. Here we report retinal alterations in a cohort of 24 patients with clinically definite (n = 20) or probable (n = 4) ALS as compared to matched controls. High‐resolution spectral domain optical coherence tomography with retinal segmentation revealed a subtle reduction in the macular thickness and the retinal nerve fiber layer (RNFL) as well as a marked thinning of the inner nuclear layer (INL). Our data indicate an unprecedented retinal damage pattern and suggest neurodegeneration beyond the motor system in this disease.


BMC Neurology | 2014

Interferon-β-related tumefactive brain lesion in a Caucasian patient with neuromyelitis optica and clinical stabilization with tocilizumab

Jens Harmel; Marius Ringelstein; Jens Ingwersen; Christian Mathys; Norbert Goebels; Hans-Peter Hartung; Sven Jarius; Orhan Aktas

BackgroundNeuromyelitis optica (NMO) is a severely disabling inflammatory disorder of the central nervous system and is often misdiagnosed as multiple sclerosis (MS). There is increasing evidence that treatment options shown to be beneficial in MS, including interferon-β (IFN-β), are detrimental in NMO.Case presentationWe here report the first Caucasian patient with aquaporin 4 (AQP4) antibody (NMO-IgG)-seropositive NMO presenting with a tumefactive brain lesion on treatment with IFN-β. Disease started with relapsing optic neuritis and an episode of longitudinally extensive transverse myelitis (LETM) in the absence of any brain MRI lesions or cerebrospinal fluid-restricted oligoclonal bands. After initial misdiagnosis of multiple sclerosis (MS) the patient received subcutaneous IFN-β1b and, subsequently, subcutaneous IFN-β1a therapy for several years. Under this treatment, the patient showed persisting relapse activity and finally presented with a severe episode of subacute aphasia and right-sided hemiparesis due to a large T2 hyperintensive tumefactive lesion of the left brain hemisphere and a smaller T2 lesion on the right side. Despite rituximab therapy two further LETM episodes occurred, resulting in severe neurological deficits. Therapeutic blockade of the interleukin (IL)-6 signalling pathway by tocilizumab was initiated, followed by clinical and radiological stabilization.ConclusionOur case (i) illustrates the relevance of correctly distinguishing NMO and MS since these disorders differ markedly in their responsiveness to immunomodulatory and -suppressive therapies; (ii) confirms and extends a previous report describing the development of tumefactive brain lesions under IFN-β therapy in two Asian NMO patients; and (iii) suggests tocilizumab as a promising therapeutic alternative in highly active NMO disease courses.


Neurology | 2015

Retinal pathology in idiopathic moyamoya angiopathy detected by optical coherence tomography.

Philipp Albrecht; Christine Blasberg; Sebastian Lukas; Marius Ringelstein; Ann-Kristin Müller; Jens Harmel; Ella-Maria Kadas; David Finis; Rainer Guthoff; Orhan Aktas; Hans-Peter Hartung; Friedemann Paul; Alexander U. Brandt; Peter Berlit; Axel Methner; Markus Kraemer

Objective: To investigate whether patients with moyamoya angiopathy without obvious retinal pathologies such as retinal infarctions or the congenital morning glory anomaly may have subtle subclinical retinal changes. Methods: In this cross-sectional study, spectral domain optical coherence tomography was used to analyze the retinal morphology of 25 patients with idiopathic moyamoya angiopathy and 25 age- and sex-matched healthy controls. We analyzed the retinal vasculature with blue laser autofluorescence, lipofuscin deposits with MultiColor confocal scanning laser ophthalmoscopy, and the optic nerve head (ONH) volume with a custom postprocessing algorithm. In addition to the total retinal thickness, semiautomated segmentation was used for segmentation of retinal layers in macular cross scans, macular volume scans, and peripapillary ring scans. Results: The main finding was a pronounced reduction of the ONH volume in moyamoya angiopathy compared with controls (0.76 ± 0.45 mm3 and 1.47 ± 0.50 mm3, respectively; p < 0.0001), which was associated with a less pronounced reduction of the retinal nerve fiber layer in macular volume scans (0.97 ± 0.11 mm3 and 1.10 ± 0.10 mm3, respectively; p < 0.001). Autofluorescence and MultiColor confocal scanning laser ophthalmoscopy images revealed no pathologies except for one branch retinal artery occlusion. Conclusion: Our results indicate that even patients with moyamoya angiopathy who do not have obvious retinal abnormalities have retinal abnormalities. These can be detected by spectral domain optical coherence tomography, and the association of ONH abnormalities with the vascular changes may suggest that idiopathic moyamoya angiography is a systemic disease involving abnormalities of the early mesodermal development.


Multiple sclerosis and related disorders | 2015

Acetazolamide therapy in a case of fingolimod-associated macular edema: early benefits and long-term limitations

Katharina Schröder; David Finis; Jens Harmel; Marius Ringelstein; Hans-Peter Hartung; Gerd Geerling; Orhan Aktas; Rainer Guthoff

UNLABELLED Fingolimod is a potent drug in relapsing forms of multiple sclerosis. Visual impairment due to fingolimod-associated macular edema (FAME) usually leads to discontinuation of fingolimod therapy. METHODS We report on a 24-year old woman with bilateral FAME. RESULTS We continued fingolimod and added oral acetazolamide, which led to recovery of visual acuity and regression of macular edema. However, fingolimod had to be discontinued when fluorescein angiography revealed an enlarged foveal avascular zone. DISCUSSION AND CONCLUSION Oral acetazolamide might be a treatment option for FAME, while ischemic conversion may be limiting. Ophthalmologic assessments are mandatory for follow-up when fingolimod therapy is continued after onset of FAME.


Nervenarzt | 2014

Contribution of spinal cord biopsy to the differential diagnosis of longitudinal extensive transverse myelitis

Marius Ringelstein; Orhan Aktas; Jens Harmel; D. Prayer; Sven Jarius; Brigitte Wildemann; H.-P. Hartung; S. Salhofer-Polanyi; F. Leutmezer; Paulus S. Rommer

BACKGROUND Neuromyelitis optica spectrum disorders (NMOSD) are characterized by recurrent optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM) as well as the serological detection of antibodies to aquaporin-4 (AQP4-ab). However, longitudinal extensive spinal cord lesions are not pathognomonic for NMOSD as they can also occur in systemic autoimmune diseases or mimic spinal cord tumors. OBJECTIVES/METHODS We report a female patient who initially presented with a subacute spinal syndrome and a longitudinal spinal cord lesion on magnetic resonance imaging (MRI). As the brain MRI showed only unspecific white matter lesions and the cerebrospinal fluid was normal, a spinal cord biopsy was performed to exclude malignancies and revealed inflammatory demyelinating changes. In addition, after several deep vein thromboses and the detection of antiphospholipid antibodies, an antiphospholipid syndrome (APS) was diagnosed. Many years after the spinal cord biopsy, AQP4-ab were tested and found to be positive. We discuss the important differential diagnoses of LETM, give an overview of previously reported NMOSD cases in which a spinal cord biopsy was performed and highlight the crucial role of AQP4-ab testing for the differential diagnosis of longitudinal spinal cord lesions. RESULTS/CONCLUSIONS Considering possible serious sequelae of spinal biopsy procedures, testing for AQP4-ab is mandatory in patients with unclear longitudinally extensive spinal cord lesions and should be performed preoperatively in all cases. In light of the heterogeneity of available assays, different detection methods should be used in doubtful cases. The relationship between NMO and APS needs further clarification; however, AQP4 IgG testing is recommended in patients presenting with APS and myelitis, optic neuritis or brainstem encephalitis.ZusammenfassungHintergrundNeuromyelitis-optica-Spektrum-Erkrankungen (NMOSD) sind klinisch durch rezidivierende Optikusneuritiden (ON) und langstreckige extensive transverse Myelitiden (LETM) sowie serologisch durch den spezifischen Aquaporin-4-Antikörper (AQP4-AK) charakterisiert. LETM sind aber nicht pathognomonisch für NMOSD, sondern können auch gesondert im Rahmen systemischer Autoimmunerkrankungen auftreten oder spinale Tumoren imitieren.Ziel der Arbeit und MethodenWir beschreiben hier eine Patientin mit einem subakuten spinalen Syndrom und Nachweis einer langstreckigen spinalen Läsion in der MRT. Bei unauffälligem Liquorbefund und nur unspezifisch veränderter kranialer MRT erfolgte zum Ausschluss einer Neoplasie eine spinale Biopsie, die entzündlich-demyelinisierende Veränderungen zeigte. Zusätzlich wurde nach mehreren Thrombosen der Extremitäten und wiederholtem Nachweis von Antiphospholipid-AK ein Antiphospholipidsyndrom (APS) diagnostiziert. Erst später erfolgte eine AQP4-AK-Testung, die positiv ausfiel. Wir stellen hier die relevanten Differenzialdiagnosen der LETM dar, geben eine Literaturübersicht über weitere Fälle spinaler Biopsien von NMOSD-Patienten und erläutern den Nutzen der AQP4-AK-Testung in der Differenzialdiagnostik langstreckiger Myelonläsionen.Ergebnis und DiskussionAngesichts möglicher perioperativer Komplikationen ist eine AQP4-AK-Testung zur diagnostischen Abklärung einer langstreckigen Myelonformation vor einer diagnostischen spinalen Biopsie obligat, unter Umständen auch mit unterschiedlichen Testverfahren. Eine Assoziation zwischen NMO und APS wurde in der Vergangenheit erst selten beschrieben, jedoch sollte bei allen Patienten mit APS und NMOSD-typischen Symptomen (langstreckige Myelitis, Optikusneuritis, Hirnstammenzephalitis) eine AQP4-AK-Testung erfolgen.SummaryBackgroundNeuromyelitis optica spectrum disorders (NMOSD) are characterized by recurrent optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM) as well as the serological detection of antibodies to aquaporin-4 (AQP4-ab). However, longitudinal extensive spinal cord lesions are not pathognomonic for NMOSD as they can also occur in systemic autoimmune diseases or mimic spinal cord tumors.Objectives/methodsWe report a female patient who initially presented with a subacute spinal syndrome and a longitudinal spinal cord lesion on magnetic resonance imaging (MRI). As the brain MRI showed only unspecific white matter lesions and the cerebrospinal fluid was normal, a spinal cord biopsy was performed to exclude malignancies and revealed inflammatory demyelinating changes. In addition, after several deep vein thromboses and the detection of antiphospholipid antibodies, an antiphospholipid syndrome (APS) was diagnosed. Many years after the spinal cord biopsy, AQP4-ab were tested and found to be positive. We discuss the important differential diagnoses of LETM, give an overview of previously reported NMOSD cases in which a spinal cord biopsy was performed and highlight the crucial role of AQP4-ab testing for the differential diagnosis of longitudinal spinal cord lesions.Results/conclusionsConsidering possible serious sequelae of spinal biopsy procedures, testing for AQP4-ab is mandatory in patients with unclear longitudinally extensive spinal cord lesions and should be performed preoperatively in all cases. In light of the heterogeneity of available assays, different detection methods should be used in doubtful cases. The relationship between NMO and APS needs further clarification; however, AQP4 IgG testing is recommended in patients presenting with APS and myelitis, optic neuritis or brainstem encephalitis.

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Rainer Guthoff

University of Düsseldorf

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David Finis

University of Düsseldorf

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Friedemann Paul

Humboldt University of Berlin

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