Objective: In rare cases, Lyme neuroborreliosis (LNB) can induce cerebral vasculitis leading to severe stenosis of the cerebral vasculature and consecutive ischemia. Therapy is based on anti-biotic treatment of the tick-borne disease, whereas interventional therapeutic options have not been assessed yet. Material and Methods: We report on a patient with LNB and concomitant stenoses and progressive and fatal vasculitis of the cerebral vessels despite all therapeutic efforts by the departments of neurology and interventional neuroradiology. In this context, we also conducted a literature review on endovascular treatment of LNB-associated cerebral ischemia. Results: A 52-year-old female presented with transient neglect and psychomotor slowdown (initial NIHSS = 0). MRI and serology led to the diagnosis of basal meningitis due to LNB with vasculitis of cerebral arteries. Despite immediate treatment with antibiotics and steroids, neurologic deterioration (NIHSS 8) led to an emergency angiography on day 2 after admission. Hemodynamically relevant stenoses of the MCA were treated via spasmolysis and PTA, leading to almost complete neurological recovery. Despite intensified medical treatment, the vasculitis progressed and could only be transiently ameliorated via repetitive spasmolysis. On day 19, she again presented with significant neurologic deterioration (NIHSS 9), and PTA and stenting of the nearly occluded MCA were performed with a patent vessel, initially without hemorrhagic complications. Despite all therapeutic efforts and preserved stent perfusion, vasculitis worsened and the concurrent occurrence of subdural hemorrhage led to the death of the patient. Conclusion: Neuroradiological interventions, i.e., spasmolysis, PTA, and, if necessary, stenting, can and should be considered in cases of LNB-induced vasculitis and stroke that are refractory to best medical treatment alone. Key point: Neuroradiological interventions can be considered in patients with vascular complications of Lyme neuroborreliosis as an additional extension of the primary drug therapy.

Objective To assess the sensitivity/specificity of tumor detection by T1 contrast enhancement in intraoperative MRI (ioMRI) in comparison to histopathological assessment as the gold standard in patients receiving surgical resection of grade IV glioblastoma. Materials and Methods 68 patients with a primary or a recurrent glioblastoma scheduled for surgery including fluorescence guidance and neuronavigation were included (mean age: 59 years, 26 female, 42 male patients). The ioMRI after the first resection included transverse FLAIR, DWI, T2-FFE and T1 – 3 d FFE +/- GD-DPTA. The second resection was performed whenever residual contrast-enhancing tissue was detected on ioMRI. Resected tissue samples were histopathologically evaluated (gold standard). Additionally, we evaluated the early postoperative MRI scan acquired within 48 h post-OP for remaining enhancing tissue and compared them with the ioMRI scan. Results In 43 patients ioMRI indicated residual tumorous tissue, which could be confirmed in the histological specimens of the second resection. In 16 (4 with recurrent, 12 with primary glioblastoma) cases, ioMRI revealed truly negative results without residual tumor and follow-up MRI confirmed complete resection. In 7 cases (3 with recurrent, 4 with primary glioblastoma) ioMRI revealed a suspicious result without tumorous tissue in the histopathological workup. In 2 (1 for each group) patients, residual tumorous tissue was detected in spite of negative ioMRI. IoMRI had a sensitivity of 95 % (94 % recurrent and 96 % for primary glioblastoma) and a specificity of 69.5 % (57 % and 75 %, respectively). The positive predictive value was 86 % (84 % for recurrent and 87 % for primary glioblastoma), and the negative predictive value was 88 % (80 % and 92 %, respectively). Conclusion ioMRI is effective for detecting remaining tumorous tissue after glioma resection. However, scars and leakage of contrast agent can be misleading and limit specificity. Key points Citation Format

For patients with symptomatic acute occlusions of the internal carotid artery below the circle of Willis, endovascular and best medical treatment were both effective and safe therapeutic options.

Purpose Recent retrospective studies have proposed a high correlation between atrophy of swallowing muscles, age, severity of dysphagia and aspiration status based on computed tomography (CT). However, ionizing radiation poses an ethical barrier to research in prospective non-patient populations. Hence, there is a need to prove the efficacy of techniques that rely on noninvasive methods and produce high-resolution soft tissue images such as magnetic resonance imaging (MRI). The objective of this study was therefore to compare the segmentation results of swallowing muscles using CT and MRI. Methods Retrospective study of 21 patients (median age: 46.6; gender: 11 female) who underwent CT and MRI of the head and neck region within a time frame of less than 50 days because of suspected head and neck cancer using contrast agent. CT and MR images were segmented by two blinded readers using Medical Imaging Toolkit (MITK) and both modalities were tested (with the equivalence test) regarding the segmented muscle volumes. Adjustment for multiple testing was performed using the Bonferroni test and the potential time effect of the muscle volumes and the time interval between the modalities was assessed by a spearman correlation. The study was approved by the local ethics committee. Results The median volumes for each muscle belly of the digastric muscle derived from CT were 3051 mm³ (left) and 2969 mm³ (right), and from MRI they were 3218 mm³ (left) and 3027 mm³ (right). The median volume of the geniohyoid muscle was 6580 mm³ on CT and 6648 mm³ on MRI. The interrater reliability was high for all segmented muscles. The mean time interval between the CT and MRI examinations was 34 days (IQR 25; 41). The muscle differences of each muscle between the two modalities did not reveal significant correlation to the time interval between the examinations (digastric left r = 0.003 and digastric right r = –0.008; geniohyoid muscle r = 0.075). Conclusion CT-based segmentation and MRI-based segmentation of the digastric and geniohyoid muscle are equally feasible. The potential advantage of MRI for prospective studies is the absence of ionizing radiation. Key Points Citation Format Einleitung Retrospektive, auf CT-Daten basierende Studien, beschreiben eine hohe Korrelation zwischen einer Atrophie der Schluckmuskulatur und dem Alter der Patienten, sowie dem Schweregrad einer Dysphagie und der Aspirationsgefahr. Die ionisierende Strahlung stellt bei CT-Untersuchungen jedoch eine ethische Barriere für eine weitere Evaluation dieser Resultate mittels prospektiver Studien dar. Daher besteht ein Bedarf die Effektivität anderer Methoden, die ohne Strahlung auskommen und hochwertige Weichteilkontraste liefern, zu evaluieren. Das Ziel der vorliegenden Studie war es daher die Muskel-Volumetrie der Schluckmuskultur von Patienten in CT und MRT zu vergleichen. Methoden Retrospektive Studie von 21 Patienten (Medianes Alter 46,6 Jahre; Geschlecht: 11 Frauen) die ein CT und MRT der Halsregion in einem Zeitfenster von weniger als 50 Tagen bei Verdacht auf eine Neoplasie der Halsregion erhalten haben. Die CT’s und MRT’s wurden mittels Medical Imaging Toolkit (MITK) segmentiert und die erhaltenen Muskelvolumina wurden mittels Äquivalenztest getestet. Multiples Testen wurden mittels Bonferroni-Test korrigiert und der mögliche Einfluss der Zeit zwischen den Untersuchungen wurde mittels Korrelationsanalyse getestet. Das Einverständnis des lokalen Ethikkomitees liegt vor. Ergebnisse Die medianen Volumina für den Musculus digastricus im CT betragen 3051 mm³ (links) und 2969 mm³ (rechts), und im MRT 3218 mm³ (links) und 3027 mm³ (rechts). Das mediane Volumen des Musculus geniohyoideus betrug im CT 6580 mm³ und im MRT 6648 mm³. Die Interrater Reliabilität war für alle segmentierten Muskeln hoch. Das mittlere Zeitintervall zwischen CT und MRT betrug 34 Tage (IQR 25; 41). Es lag keine signifikante Assoziation der Zeit zwischen den Untersuchungen und dem Unterschied der Muskelvolumina vor (linker M. digastricus r = 0,003 und rechter M. digastricus r = –0,008; M. geniohyoideus r = 0,075). Schlussfolgerung Die CT und MRT basierte Volumetrie der Schluckmuskulatur ist möglich und gleichwertig. Der potentielle Vorteil der MRT ist die Anwendbarkeit in prospektiven Studien ohne ionisierende Strahlung. Kernaussagen

Unlike puerperal peripheral nerve lesions, mononeuropathy during pregnancy is rarely encountered. We report a case of bilateral relapsing-remitting sciatic nerve palsy during two pregnancies. An extensive literature search in PubMed brought no similar cases. A healthy young woman presented with initially unilateral sciatic nerve palsy, which manifested and worsened during the early phases of two successive pregnancies. Electrophysiology revealed axonal lesion of the sciatic nerve with predominant affection of the peroneal part. Extensive laboratory examination including cerebrospinal fluid examination was unremarkable. MR imaging was compatible with bilateral intraneural perineurioma. Recurrent occurrence during two pregnancies and an anamnestic relationship between intermediate worsening of the paresis and the menstrual cycle suggested hormone-dependency of the tumor. However, response to repeated intravenous immunoglobuline (IVIG) therapy during pregnancy and shortly after childbirth resulted in partial reversion of foot drop. This was also indicative of an immunoneuropathy. Nerve biopsy was not performed because of clinical improvement. The precise underlying neuropathological mechanism remained unclear. To increase knowledge and awareness of this rare entity, potential etiologies of mononeuropathies during pregnancy are discussed in the context of this case report. In the rare occasion of peripheral nerve mononeuropathy during pregnancy, in which therapeutic opportunities are limited, IVIG therapy may be an option when the etiology cannot clearly be determined after thorough medical investigation.

Objective: Until now, giant intracranial aneurysms (GIAs) have in many cases been a vascular disease that was difficult or impossible to treat, not least due to the lack of availability of a large-format stent. In this multicentre study, we report on the first five clinical applications of the Accero^®-Rex-Stents (Acandis, Pforzheim, Germany) in the successful treatment of fusiform cerebral giant aneurysms. Material and Methods: The Accero^®-Rex-Stents are self-expanding, braided, fully radiopaque Nitinol stents designed for aneurysm treatment. The stent is available in three different sizes (diameter 7–10 mm, length 30–60 mm) and intended for endovascular implantation in vessels with diameters of 5.5–10 mm. Results: Five patients (all male, age 54.4 ± 8.1 years) with large fusiform aneurysms of the posterior circulation were treated endovascularly using the Accero^®-Rex-Stents. There were no technical complications. One major ischemic complication occurred. A significant remodeling and reduction in the size of the stent-covered aneurysms was already seen in the short-term post-interventional course. Conclusions: The Accero^®-Rex-Stents were successfully and safely implanted in all five patients with fusiform giant aneurysms, showing technical feasibility with promising initial results and significant aneurysm size reduction in already available follow-up imaging. Key point: With the Accero-Rex-Stents, a new device is available that offers another treatment option for rare cerebral fusiform giant aneurysms with very large parent vessels.