Friedrich Götz

eLearning in education and advanced training in neuroradiology: introduction of a web-based teaching and learning application.

IntroductionNew information technologies offer the possibility of major improvements in the professional education and advanced training of physicians. The web-based, multimedia teaching and learning application Schoolbook has been created and utilized for neuroradiology.MethodsSchoolbook is technically based as a content management system and is realized in a LAMP environment. The content is generated with the help of the developed system and stored in a database. The layout is defined by a PHP application, and the webpages are generated from the system.ResultsSchoolbook is realized as an authoring tool so that it can be integrated into daily practice. This enables the teacher to autonomously process the content into the web-based application which is used for lectures, seminars and self-study. A multimedia case library is the central building block of Schoolbook for neuroradiology, whereby the learner is provided with original diagnostic and therapeutic data from numerous individual cases. The user can put individual emphasis on key learning points as there are various ways to work with the case histories. Besides the case-based way of teaching and learning, a systematically structured way of dealing with the content is available.ConclusioneLearning offers various opportunities for teaching and learning in academic and scientific as well as in economic contexts. Web-based applications such as Schoolbook may be beneficial not only for basic university education but also for the realization of international educational programmes such as the European Master of Medical Science with a major in neuroradiology.

Microsurgical clipping of previously coiled intracranial aneurysms.

OBJECTIVE Endovascular coiling techniques for the treatment of intracranial aneurysms have rapidly developed as an alternative option to surgical clipping. A distinct problem after endovascular coiling is the management of a residual aneurysm neck due to incomplete filling, compaction of coils or regrowth of the aneurysm. Treatment options in this situation include surgical clipping, re-coiling, stent implantation or observation. METHODS From June 2006 to August 2011, 15 patients underwent surgical clipping of residual or recurrent aneurysms after previous endovascular treatment. The mean age of the patients was 50.6 years (range, 27-85 years). The mean interval between coiling and clipping was 76.5 weeks (range, 0-288 weeks). RESULTS Thirteen patients revealed a regrowth of coiled aneurysms, and in 5 patients compaction of coils was present. Coil extrusion was observed in 9 patients intraoperatively. In case of coil obstruction at the aneurysmal neck during surgery, coils were partially or completely removed. In all cases complete occlusion of the aneurysms was surgically achieved. CONCLUSION Coiled aneuryms with incomplete occlusion, coil compaction or regrowth of the aneurysmal neck can be successfully treated with microsurgical clipping. Coil extrusion was more often observed intraoperatively than expected. Complete occlusion of the aneurysm can be performed safely, even if loops of coils protrude into the aneurysmal neck. In these cases intraoperative removal of the coils enables secure closure of the aneurysm with a surgical clip.

Treatment of Mandibular High-Flow Vascular Malformations: Report of 2 Cases

Two cases of high-flow vascular malformations affecting the mandible are presented. Manifesting mainly in childhood, intraosseous arteriovenous malformations are extremely rare morphologic errors of vascular morphogenesis that can lead to life-threatening hemorrhage without appropriate treatment. A dentist referred an 8-year-old girl with radiolucency in the left mandible and supraocclusion of the mandibular left first molar. During biopsy, massive bleeding occurred. Computed tomographic scan with contrast medium showed a vascular malformation. Arterial embolization was performed followed by surgical resection. Autologous bone transplantation and resorbable osteosynthesis plates were used for reconstruction. The second patient, a 15-year-old girl, had intense bleeding from the periodontal space of a highly mobile right mandibular second molar. Intraoral clinical examination showed a painless pulsatile swelling in the right buccal vestibule. Computed tomographic angiogram displayed an extensive vascular malformation involving the right mandible. After successful selective embolization, surgical resection, and reconstruction with autologous bone, transplantation was performed. Preoperative embolization is a low-risk procedure in highly vascularized lesions. It is a recommended procedure to avoid the increased risk of an emergency operation, to minimize blood loss during surgery, and to better plan reconstructive surgery.

De Novo Arteriovenous Malformation Growth Secondary to Implantation of Genetically Modified Allogeneic Mesenchymal Stem Cells in the Brain.

BACKGROUND AND IMPORTANCE Local biological drug delivery in the brain is an innovative field of medicine that developed rapidly in recent years. Our report illustrates a unique case of de novo development of a cerebral arteriovenous malformation (AVM) after implantation of genetically modified allogeneic mesenchymal stem cells in the brain. CLINICAL PRESENTATION A 50-year-old man was included in a prospective clinical study (study ID number CM GLP-1/01, 2007-004516-31) investigating a novel neuroprotective approach in stroke patients to prevent perihematomal neuronal damage. In this study, alginate microcapsules containing genetically modified allogeneic mesenchymal stem cells producing the neuroprotective glucagon-like peptide-1 (GLP-1) were implanted. Three years later, the patient presented with aphasia and a focal seizure due to a new left frontal intracerebral hemorrhage. Angiography revealed a de novo left frontal AVM. CONCLUSION The development of an AVM within a period of 3 years after implantation of the glucagon-like peptide-1-secreting mesenchymal stem cells suggests a possible relationship. This case exemplifies that further investigations are necessary to assess the safety of genetically modified cell lines for local biological drug delivery in the brain.

Intramedullary spinal cord implantation of human CD34+ umbilical cord-derived cells in ALS.

Abstract Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disorder with marginal therapeutic options. Degeneration of motor neurons in the primary motor cortex, brainstem and spinal cord lead to rapidly progressive paralysis and finally to death due to respiratory failure. As pharmacological therapies have failed to provide sufficient neuroprotective effects in ALS, transplantation of stem or progenitor cells is considered a promising treatment strategy. Cell transplantation approaches in ALS mainly aim to generate a neuroprotective environment for degenerating motor neurons by transplantation of non-neuronal cells, rather than to replace lost motor neurons. We present a 63-year-old male patient suffering from ALS who underwent intramedullary thoracic spinal cord implantation of human CD34+ umbilical cord-derived haematopoietic progenitor cells with a three-year follow up after transplantation.

Quantitative MRI shows cerebral microstructural damage in hemolytic–uremic syndrome patients with severe neurological symptoms but no changes in conventional MRI

IntroductionSevere neurological symptoms in Shiga toxin-producing Escherichia coli infection associated hemolytic–uremic syndrome (STEC–HUS) are often accompanied by none or only mild alterations of cerebral magnetic resonance imaging (MRI). This study aims to analyze if quantitative MRI is able to reveal cerebral pathological alterations invisible for conventional MRI.MethodsIn nine patients with STEC–HUS associated severe neurological symptoms but inconspicuous cerebral MRI findings maps of the parameters T2 relaxation time, relative proton density (PD), apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were generated. Quantitative values of these parameters were measured at the basal ganglia, thalamus, and white matter of the frontal and parietal lobe and compared to those of nine age- and sex-matched controls.ResultsSignificant T2 prolongation (p < 0.01) was found in the basal ganglia of all patients compared to controls. PD and ADC were not significantly altered. A significant reduction of FA in patients was seen at caput nuclei caudati (p < 0.01).ConclusionProlonged T2 relaxation time indicates cerebral microstructural damages in these patients despite their inconspicuous MRI findings. T2 relaxometry could be used as a complementary tool for the assessment of metabolic–toxic brain syndromes.

Amyotrophic lateral sclerosis (ALS) and mirror movements in a patient with polymicrogyria

We report on a case of polymicrogyria with benign childhood epilepsy and amyotrophic lateral sclerosis (ALS). While performing dexterity tasks with either hand, strong unsustained mirror movements of the unintended hand were observed. The patient was seen over a period of three years and, as often seen in ALS, there was a moderate progress of the motor neuron disease affecting the upper and lower motor neuron in an asymmetrical manner. In addition, more rapidly progressive bulbar symptoms could be observed by the clinical and neurophysiological examination. MRI revealed polymicrogyria of the right frontal lobe with irregular bumpy inner and outer surface and abnormally thick and smooth cortex, dysplastic insular cortex and asymmetrically widened Sylvial fissure. No signs of atrophy, especially of the motorcortex and corticospinal tract were observed. The corpus callosum was completely developed and of normal size. We hypothesize an enrolment of the dysplastic right frontal lobe in the pathophysiology of the observed mirror movements.

Zervikaler Abszess nach lumbaler epiduraler Schmerztherapie

ZusammenfassungBericht über eine 49-jährige adipöse Diabetikerin, die wegen langjähriger lumbaler Rückenschmerzen nach zahlreichen, letztendlich erfolglosen Behandlungen unterschiedlichster Art mit computertomographiegestützten epiduralen Injektionen therapiert wurde. Im Magnetresonanztomogramm wurden degenerative Veränderungen der LWS (Lendenwirbelsäule), insbesondere im Bewegungssegment LW4/5, ein linksseitiger Bandscheibenvorfall ohne Nervenwurzelkompression, Facettengelenkarthrosen und Gefügestörungen nachgewiesen. Nach der zuletzt durchgeführten lumbalen epiduralen Injektion mit kristallinem Kortikoid entwickelten sich eine rasch fortschreitende lokale Infektion und Sepsis. Schließlich kam es zu einer Tetraparese infolge eines hochzervikalen epiduralen Abszesses. Es wurde Klage gegen die radiologische Gemeinschaftspraxis eingereicht, welche die lumbale Schmerztherapie durchgeführt hatte. Das Gericht hat die Klage als unbegründet abgewiesen und sich dabei maßgeblich auf das neuroradiologische Gutachten und die mündlichen Erläuterungen gestützt.Abstract A 49-year-old female with diabetes and chronic low back pain was treated with computed tomography-guided injections after years of unsuccessful pain management. Magnetic resonance imaging (MRI) demonstrated degenerative changes of the lumbar spine with disk herniation, facet joint degeneration, and instability of the presacral segment. Following epidural steroid injection, local infection and sepsis occurred and, finally, tetraparesis developed. A cervical epidural abscess was demonstrated on follow-up MRI and evacuation was performed. The patient survived severely handicapped. Legal proceedings were initiated against the radiologists. They were accused of causing damage to the patient. The plaint was defeated with special reference to the report and expertise of the neuroradiologic evidence.A 49-year-old female with diabetes and chronic low back pain was treated with computed tomography-guided injections after years of unsuccessful pain management. Magnetic resonance imaging (MRI) demonstrated degenerative changes of the lumbar spine with disk herniation, facet joint degeneration, and instability of the presacral segment. Following epidural steroid injection, local infection and sepsis occurred and, finally, tetraparesis developed. A cervical epidural abscess was demonstrated on follow-up MRI and evacuation was performed. The patient survived severely handicapped. Legal proceedings were initiated against the radiologists. They were accused of causing damage to the patient. The plaint was defeated with special reference to the report and expertise of the neuroradiologic evidence.

CSF Levels of Angiopoietin-2 Do Not Differ between Patients with CSF Fluid Leakage Syndrome and Controls

CSF abnormalities have been reported in CSF leakage syndrome. However, the mechanism for these CSF changes is actually unknown and they may indicate impaired CSF flow or blood-CSF barrier. Angiopoietin-2 (Ang-2), a protein which is expressed and released by endothelial cells, has been associated with increased vascular permeability. In the assumption that CSF changes are due to an impaired blood-CSF barrier, we hypothesized that subjects with persistent CSF leakage may have increased CSF Ang-2 levels. We enrolled 10 subjects with a clinically definite diagnosis of persisting CSF leakage syndrome and 10 control subjects. In CSF analyses, CSF to serum albumin ratio (Qalb) was the most frequently increased parameter indicating a disturbed blood-CSF barrier function. Comparison of the mean CSF Ang-2 levels, CSF to serum Ang-2 ratio (QAng-2), and QAng-2/Qalb between the control and CSF leakage patients did not show any significant difference. We suggest that the increase of Qalb results from a low CSF flow. Future studies with phase contrast-MRI in conjunction with CSF analyses before and after epidural blood patch treatment are required to address this question. It would be of particular interest whether Qalb can be used as a marker for successful nontargeted epidural blood patch treatment.

Spontaneous closure of a dural arteriovenous fistula

Spontaneous closure of a dural arteriovenous fistula (dAVF) is a rare condition and only a few cases have been reported since its first description in 1976. We report delayed and progressive spontaneous closure of a dAVF after massive intracerebral hemorrhage documented by angiographic studies before and after bleeding. To our knowledge, this is the first report to document gradual closure of a dAVF by serial angiographic studies. The mechanism of spontaneous closure of dAVFs has not been fully elucidated. We suggest different factors for consideration from previously published data and show how each of these factors can influence the others.