G Schuierer

University Hospital Regensburg, Ratisbon, Bavaria, Germany

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Publications (204)710.4 Total impact

  • C M Wendl · E M Jung · J Eiglsperger · G Schuierer
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    ABSTRACT: Purpose: The main goal of cerebral endovascular aneurysm therapy is the complete occlusion of the aneurysm. Along with the development of new aneurysm treatment devices, repeated controls are necessary. We examined whether contrast-enhanced ultrasound can help to monitor aneurysms after endovascular treatment. Materials and Methods: We prospectively examined 12 patients after coiling (7 patients) or flow diverter (FD) implantation (5 patients). These patients were examined with transcranial contrast-enhanced ultrasound using a matrix probe (1 - 5 MHz). Doppler sonography, Power Doppler, contrast harmonic imaging (CHI) and Power Doppler sonography (CPD) were included in the examination. Digital subtraction angiography with 3 D reconstructions served as the gold standard. Two radiologists decided in consensus about the degree of aneurysm occlusion separately in CEUS and digital subtraction angiography using a 4-point grading scheme. Results: The degree of occlusion of the 12 aneurysms comparing the two imaging modalities was identical in 10 cases. In two cases CHI and CPD showed a small aneurysm remnant after coiling in the center of the coil pack while in digital subtraction angiography the aneurysms seemed completely occluded. Conclusion: The investigation indicates that contrast-enhanced ultrasound is a supportive, noninvasive method for post-interventional controls of intracranial aneurysms due to its ability to display not only macro- but also microvascularization. © Georg Thieme Verlag KG Stuttgart · New York.
    Ultraschall in der Medizin 01/2015; 36(02):168-173. DOI:10.1055/s-0034-1398835 · 4.65 Impact Factor
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    ABSTRACT: Intracranial hemorrhages are associated with high rates of disability and mortality. Telemedicine in general provides clinical healthcare at a distance by using videotelephony and teleradiology and is used particularly in acute stroke care medicine (TeleStroke). TeleStroke considerably improves quality of stroke care (for instance, by increasing thrombolysis) and may be valuable for the management of intracranial hemorrhages in rural hospitals and hospitals lacking neurosurgical departments, given that surgical/interventional therapy is only recommended for a subgroup of patients. The aim of this study was to analyze the frequency, anatomical locations of intracranial hemorrhage, risk factors, and the proportion of patients transferred to specialized hospitals. We evaluated teleconsultations conducted between 2008 and 2010 in a large cohort of patients consecutively enrolled in the Telemedical Project for Integrated Stroke Care (TEMPiS) network. In cases in which intracranial hemorrhage was detected, all images were re-examined and analyzed with a focus on frequency, location, risk factors, and further management. Overall, 6187 patients presented with stroke-like symptoms. Intracranial hemorrhages were identified in 631 patients (10.2%). Of these, intracerebral hemorrhages were found in 423 cases (67.0%), including 174 (41.1%) in atypical locations and 227 (53.7%) in typical sites among other locations. After 14 days of hospitalization in community facilities, the mortality rate in patients with intracranial hemorrhages was 15.1% (95/631). Two hundred and twenty-three patients (35.3%) were transferred to neurological/neurosurgical hospitals for diagnostic workup or additional treatment. Community hospitals are confronted with patients with intracranial hemorrhage, whose management requires specific neurosurgical and hematological expertise with respect to hemorrhage subtype and clinical presentation. TeleStroke networks help select patients who need advanced neurological and/or neurosurgical care. The relatively low proportion of interhospital transfers shown in this study reflects a differentiated decision process on the basis of both guidelines and standard operating procedures.
    Neuroreport 01/2015; 26(2):81-7. DOI:10.1097/WNR.0000000000000304 · 1.64 Impact Factor
  • Journal of neuroimaging: official journal of the American Society of Neuroimaging 09/2014; 25(3). DOI:10.1111/jon.12161 · 1.82 Impact Factor
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    ABSTRACT: Purpose: The BLADE (PROPELLER) technique reduces artefacts in imaging of the cervical spine in sagittal orientation, but till now failed to do so in axial orientation, because here it increased through plane CSF-flow artefacts, which spoiled the benefit of BLADE artefact reduction "in plane". The aim of this study was to compare a BLADE sequence with optimised measurement parameters in axial orientation to T2-TSE. Materials and Methods: Both sequences were compared in 58 patients with 31 discal, 16 bony and 11 spinal cord lesions. Image sharpness, reliability of spinal cord depiction, CSF flow artefacts and lesion detection were evaluated by 3 independent observers. Additionally the observers were asked which sequence they would prefer for diagnostic workup. Statistical evaluations were performed using sign and chi(2) test. Results: BLADE was significantly superior concerning image sharpness, spinal cord depiction and overall lesion detection. BLADE was rated better for most pathologies, for bony lesions the differences compared with TSE were statistically significant. Regarding CSF-flow artefacts both sequences showed no difference. All readers preferred BLADE in side by side reading. Conclusion: An optimised axial T2 BLADE sequence decreases the problems of increased through plane CSF-flow artefacts in this orientation. By reducing various other artefacts it yields better image quality and has the potential to reduce the number of non-diagnostic examinations especially in uncooperative patients.
    RöFo - Fortschritte auf dem Gebiet der R 09/2014; 36(2). DOI:10.1055/s-0034-1385179 · 1.96 Impact Factor
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    ABSTRACT: Patient: Female, 78 Final Diagnosis: Cerebral hyperperfusion syndrome Symptoms: - Medication: - Clinical Procedure: Endovascular embolectomy Specialty: Neurology. Unknown ethiology. Cerebral hyperperfusion syndrome (cHS) is a well known but rare complication after carotid endarterectomy, carotid angioplasty with stenting, and stenting of intracranial arterial stenosis. The clinical presentation may vary from acute onset of focal oedema (stroke-like presentation) and intracerbral hemorrhage to delayed (>24h hours after the procedure) presentation with seizures, focal motor weakness, or late intracerebral hemorrhage. The incidence of cHS after carotid endarterectomy ranges from 0-3% and defined as an increase of the ipsilateral cerebral blood flow up to 40% over baseline in ultrasound. We present a case of a 78-year-old woman with an acute ischemic stroke due to left side middle cerebral artery territory with right sided hemiparesis and aphasia (NIHSS 16). After systemic thrombolysis embolectomy using a retractable stent (Solitaire(®) device) was performed and resulted in complete and successful recanalization of MCA including its branches about 210 minutes after symptom onset but, partial dislocation of thrombotic material into the anterior cerebral artery (ACA). Cerebral hyperperfusion syndrome should be considered in patients with clinical deterioration after successful recanalisation and the early diagnosis and treatment may be important for neurological outcome after endovascular embolectomy.
    American Journal of Case Reports 11/2013; 14:513-7. DOI:10.12659/AJCR.889672
  • Journal of the Neurological Sciences 10/2013; 333:e438. DOI:10.1016/j.jns.2013.07.1570 · 2.26 Impact Factor
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    ABSTRACT: Purpose: Using the BLADE (PROPELLER) technique for T2-weighted MR imaging of the cervical spine has proven to be a reliable tool for reducing artifacts typically for this region. The aim of this study was to evaluate whether the application of BLADE sequences has an impact on the detection of small or low contrast spinal cord and epidural lesions.Materials and Methods: A standard TSE and a BLADE sequence were compared in 33 patients with 46 spinal cord and epidural lesions for T2-weighted sagittal imaging of the cervical spine. Image sharpness, visualization of the dura, reliability of spinal cord depiction as well as lesion contrast were evaluated by two independent readers. Additionally two experienced neuroradiologists selected in consensus the sequence they would prefer for diagnostic purposes. Statistical evaluations were performed using the sign and the χ2 test.Results: BLADE was significantly superior to TSE regarding image sharpness, visualization of the dura and reliability of spinal cord depiction. Regarding lesion contrast there was a positive trend towards the BLADE sequence. In 17 of 46 lesions, BLADE was judged superior to TSE, while TSE was favored in 10 lesions. In consensus reading both neuroradiologists preferred BLADE for overall image quality in 27 of 33 patients and for lesion contrast in 10 and TSE in 14 of the 33 patients, but 3 TSE sequences were rated as non-diagnostic regarding this criterion.Conclusion: For the detection of even small and low-contrast spinal cord lesions, BLADE is at least equivalent to TSE, yielding better overall image quality and fewer non-diagnostic images.Citation Format:
    RöFo - Fortschritte auf dem Gebiet der R 09/2013; 186(1). DOI:10.1055/s-0033-1350346 · 1.96 Impact Factor
  • Ulrich Bogdahn · Felix Schlachetzki · Gerhard Schuierer
    Stroke 08/2013; 44(9). DOI:10.1161/STROKEAHA.113.002340 · 6.02 Impact Factor
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    ABSTRACT: PURPOSE: To evaluate if the use of BLADE sequences might overcome some limitations of magnetic resonance imaging (MRI) in the extracranial head and neck, which is a diagnostically challenging area with a variety of artifacts and a broad spectrum of potential lesions. MATERIALS AND METHODS: After informed consent and Institutional Review Board approval, two different BLADE sequences with (BLADE IR) and without inversion pulse (BLADE) were compared to turbo-spin echo (TSE) with fat saturation for coronal T1-weighted postcontrast imaging of the extracranial head and neck region in 40 individuals of a routine patient collective. Visual evaluation of image sharpness, motion artifacts, vessel pulsation, contrast of anatomic structures, contrast of pathologies to surrounding tissue as well as BLADE-specific artifacts was performed by two experienced, independent readers. Statistical evaluation was done by using the Wilcoxon test. RESULTS: Both BLADE and BLADE IR were significantly superior to TSE regarding pulsation artifacts and delineation of thoracic structures. TSE provided better results concerning contrast muscle/fat tissue and contrast lymph nodes/fat. More important, it showed significantly better contrast of several lesions, facilitating the detection of patient pathology. CONCLUSION: T1-weighted coronal imaging of the extracranial head and neck region is demanding. T1-weighted BLADE sequences still have drawbacks in anatomical contrast and lesion detection but offer possibilities to achieve reasonable image quality in difficult cases with a variety of artifacts. J. Magn. Reson. Imaging 2012;. © 2012 Wiley Periodicals, Inc.
    Journal of Magnetic Resonance Imaging 03/2013; 37(3). DOI:10.1002/jmri.23843 · 2.79 Impact Factor
  • European Heart Journal 07/2012; 34(6). DOI:10.1093/eurheartj/ehs194 · 14.72 Impact Factor
  • RöFo - Fortschritte auf dem Gebiet der R 05/2012; 184(S 01). DOI:10.1055/s-0032-1311224 · 1.96 Impact Factor
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    ABSTRACT: Es werden retrospektiv der Krankheitsverlauf und die Therapie von 17 AIDS-Patienten mit progressiver multifokaler Leukoenzephalopathie (PML) analysiert und eine Zusammenfassung über die klinische Symptomatik und die Überlebenszeit gegeben. Die relative Häufigkeit der PML von AIDS-Patienten betrug 2,6%. Der Durchschnittswert der CD4-positiven Zellen lag bei 80,5±82,5/μl, nur bei einer Patientin lagen die CD4-positiven Zellen >200/μl und stiegen unter einer Dreifachkombination signifikant an, während die CD4-positiven Zellzahlen der anderen Patienten unter maximal einer Zweifachkombination nicht signifikant anstiegen. Die mittlere Überlebenszeit betrug 6,6 (1,5–20) Monate und war abhängig von der Zahl der CD4-positiven Zellen. Die Diagnose der PML kann als ausreichend sicher angesehen werden, wenn JC-Virus-DNA im Liquor nachweisbar ist, typische Veränderungen in der MRT gezeigt werden können und eine typische klinische Symptomatik vorliegt. Bis heute existiert keine etablierte effektive Therapie der PML. Einzelfallbeschreibungen über eine Therapie der PML mit Cidofovir zeigten, wie in einem der hier geschilderten Fälle, erste positive Ergebnisse. We describe retrospectively the course of 17 AIDS patients with progressive multifocal leukoencephalopathy (PML) and give a review of their clinical symptoms and survival times. The relative frequency of PML in our cohort of AIDS patients was 2.6%. The mean of CD4-positive cells was 80.5±82.5/μl. CD4-positive cells were >200/μl only in one patient and increased significantly under a combination of three antiretroviral drugs whereas, with the other patients, CD4-positive cells did not increase with a maximum of two antiretroviral drugs. The mean survival time was 6.6 (1.5–20) months and correlated positively with the number of CD4-positive cells. The diagnosis of PML can be regarded as confirmed when JC-virus DNA is detectable in cerebrospinal fluid, typical changes can be seen in MRI and typical clinical symptoms occur. No effective therapy is known to date. Single case reports on therapy with cidofovir, as in one of the cases described here, showed positive results.
    Der Nervenarzt 04/2012; 71(2):96-104. DOI:10.1007/s001150050014 · 0.86 Impact Factor
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    ABSTRACT: Cerebral amyloid angiopathy (CAA) is a degenerative disorder characterized by amyloid-β (Aβ) deposition in the blood-brain barrier (BBB). CAA contributes to injuries of the neurovasculature including lobar hemorrhages, cortical microbleeds, ischemia, and superficial hemosiderosis. We postulate that CAA pathology is partially due to Aβ compromising the BBB. We characterized 19 patients with acute stroke with "probable CAA" for neurovascular pathology based on MRI and clinical findings. Also, we studied the effect of Aβ on the expression of tight junction proteins and matrix metalloproteases (MMPs) in isolated rat brain microvessels. Two of 19 patients with CAA had asymptomatic BBB leakage and posterior reversible encephalopathic syndrome indicating increased BBB permeability. In addition to white matter changes, diffusion abnormality suggesting lacunar ischemia was found in 4 of 19 patients with CAA; superficial hemosiderosis was observed in 7 of 9 patients. Aβ(40) decreased expression of the tight junction proteins claudin-1 and claudin-5 and increased expression of MMP-2 and MMP-9. Analysis of brain microvessels from transgenic mice overexpressing human amyloid precursor protein revealed the same expression pattern for tight junction and MMP proteins. Consistent with reduced tight junction and increased MMP expression and activity, permeability was increased in brain microvessels from human amyloid precursor protein mice compared with microvessels from wild-type controls. Our findings indicate that Aβ contributes to changes in brain microvessel tight junction and MMP expression, which compromises BBB integrity. We conclude that Aβ causes BBB leakage and that assessing BBB permeability could potentially help characterize CAA progression and be a surrogate marker for treatment response.
    Stroke 11/2011; 43(2):514-23. DOI:10.1161/STROKEAHA.111.627562 · 6.02 Impact Factor
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    ABSTRACT: Regenerative strategies in the treatment of acute stroke may have great potential. Hematopoietic growth factors mobilize hematopoietic stem cells and may convey neuroprotective effects. We examined the safety, potential functional and structural changes, and CD34(+) cell-mobilization characteristics of G-CSF treatment in patients with acute ischemic stroke. Three cohorts of patients (8, 6, and 6 patients per cohort) were treated subcutaneously with 2.5, 5, or 10 µg/kg body weight rhG-CSF for 5 consecutive days within 12 hrs of onset of acute stroke. Standard treatment included i.v. thrombolysis. Safety monitoring consisted of obtaining standardized clinical assessment scores, monitoring of CD34(+) stem cells, blood chemistry, serial neuroradiology, and neuropsychology. Voxel-guided morphometry (VGM) enabled an assessment of changes in the patients' structural parenchyma. 20 patients (mean age 55 yrs) were enrolled in this study, 5 of whom received routine thrombolytic therapy with r-tPA. G-CSF treatment was discontinued in 4 patients because of unrelated adverse events. Mobilization of CD34(+) cells was observed with no concomitant changes in blood chemistry, except for an increase in the leukocyte count up to 75,500/µl. Neuroradiological and neuropsychological follow-up studies did not disclose any specific G-CSF toxicity. VGM findings indicated substantial atrophy of related hemispheres, a substantial increase in the CSF space, and a localized increase in parenchyma within the ischemic area in 2 patients. We demonstrate a good safety profile for daily administration of G-CSF when begun within 12 hours after onset of ischemic stroke and, in part in combination with routine i.v. thrombolysis. Additional analyses using VGM and a battery of neuropsychological tests indicated a positive functional and potentially structural effect of G-CSF treatment in some of our patients. German Clinical Trial Register DRKS 00000723.
    PLoS ONE 08/2011; 6(8):e23099. DOI:10.1371/journal.pone.0023099 · 3.23 Impact Factor
  • M Ertl · G Schuierer · U Bogdahn · F Schlachetzki
    Ultraschall in der Medizin 08/2011; 32(5):433-6. DOI:10.1055/s-0031-1273472 · 4.65 Impact Factor
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    Z Kohl · G Uyanik · R Lürding · G Schuierer · U Bogdahn · M Schröder · N Weidner
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    ABSTRACT: Theophylline is known to increase the risk of epileptic seizures and might have a role in seizure-induced brain damage. We present a 55-year-old man who developed an amnesic syndrome after status epilepticus, caused by accidental theophylline intoxication. Imaging studies revealed acute, selective bilateral hippocampal damage, which corresponded to severe disturbances in bilateral temporal functions on neuropsychological testing. Three months later, the memory deficits persisted, while imaging exhibited bilateral atrophy of the hippocampus. Upon his long-term, 18-month follow-up, the patient demonstrated improvements in his daily living abilities, despite the persistence of bilateral temporal deficits. This report provides evidence that theophylline has the potential to provoke permanent seizure-induced neural damage, presumably via inhibition of adenosine receptors, and especially in vulnerable regions of the brain, such as the hippocampus.
    Journal of Clinical Neuroscience 07/2011; 18(7):964-6. DOI:10.1016/j.jocn.2010.11.017 · 1.32 Impact Factor
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    ABSTRACT: We present a rare case of internal carotid artery pseudoocclusion (ICAPO) in a 60-year-old male Caucasian patient who experienced a reversible sudden loss of vision of the right eye for 10 min followed by recurrent blurring of vision as well as dysarthria and numbness in the left face. The referring ophthalmologist admitted the patient for suspicious occlusion of the internal carotid artery causing anterior ischemic optic neuropathy (AION).
    07/2011; 1(3):e62. DOI:10.4081/cp.2011.e62
  • U Hehr · G Schuierer
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    ABSTRACT: Malformations of cortical development comprise a clinically and etiologically heterogeneous group of distinct structural abnormalities of the cerebral cortex, commonly identified during MR imaging of patients with seizure disorders and/or developmental delay. MR imaging is crucial for further classification and together with additional clinical information and family history guiding specific genetic testing, which today is an integral part of the interdisciplinary diagnostic work-up and allows identification of an underlying genetic alteration in a significant subset of patients. Results of genetic testing may provide important prognostic information and subsequently support prospective therapeutic decisions. Furthermore, genetic forms of cortical malformations may be associated with a significantly increased recurrence risk for further siblings or other relatives and require genetic counselling of the family on individual risks and the options of prenatal or even preimplantation genetic diagnosis.
    Neuropediatrics 04/2011; 42(2):43-50. DOI:10.1055/s-0031-1279787 · 1.10 Impact Factor
  • Basal Ganglia 03/2011; 1(1):32. DOI:10.1016/j.baga.2011.01.060
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    ABSTRACT: Small animal models of human diseases are an indispensable aspect of pre-clinical research. Being dynamic, most pathologies demand extensive longitudinal monitoring to understand disease mechanisms, drug efficacy and side effects. These considerations often demand the concomitant development of monitoring systems with sufficient temporal and spatial resolution. This study attempts to configure and optimize a clinical 3 Tesla magnetic resonance scanner to facilitate imaging of small animal central nervous system pathologies. The hardware of the scanner was complemented by a custom-built, 4-channel phased array coil system. Extensive modification of standard sequence protocols was carried out based on tissue relaxometric calculations. Proton density differences between the gray and white matter of the rodent spinal cord along with transverse relaxation due to magnetic susceptibility differences at the cortex and striatum of both rats and mice demonstrated statistically significant differences. The employed parallel imaging reconstruction algorithms had distinct properties dependent on the sequence type and in the presence of the contrast agent. The attempt to morphologically phenotype a normal healthy rat brain in multiple planes delineated a number of anatomical regions, and all the clinically relevant sequels following acute cerebral ischemia could be adequately characterized. Changes in blood-brain-barrier permeability following ischemia-reperfusion were also apparent at a later time. Typical characteristics of intra-cerebral haemorrhage at acute and chronic stages were also visualized up to one month. Two models of rodent spinal cord injury were adequately characterized and closely mimicked the results of histological studies. In the employed rodent animal handling system a mouse model of glioblastoma was also studied with unequivocal results. The implemented customizations including extensive sequence protocol modifications resulted in images of high diagnostic quality. These results prove that lack of dedicated animal scanners shouldn't discourage conventional small animal imaging studies.
    PLoS ONE 02/2011; 6(2):e16091. DOI:10.1371/journal.pone.0016091 · 3.23 Impact Factor

Publication Stats

4k Citations
710.40 Total Impact Points

Institutions

  • 2011–2015
    • University Hospital Regensburg
      Ratisbon, Bavaria, Germany
  • 2002–2014
    • Universität Regensburg
      • Department of Neurology
      Ratisbon, Bavaria, Germany
  • 2004–2013
    • Bezirksklinikum Regensburg
      Ratisbon, Bavaria, Germany
  • 1991–2012
    • University of Münster
      • • Department of Neurology
      • • Clinic for Nuclear Medicine
      • • Department of Clinical Radiology
      Muenster, North Rhine-Westphalia, Germany
    • Universitätsklinikum Erlangen
      • Department of Neuroradiology
      Erlangen, Bavaria, Germany
  • 1996–2010
    • Universitätsklinikum Münster
      Muenster, North Rhine-Westphalia, Germany
  • 1987–1991
    • Friedrich-Alexander Universität Erlangen-Nürnberg
      • Department of Neurology
      Erlangen, Bavaria, Germany