Abstract
Together with
Association of Neurosurgical Nursing Staff Switzerland
May 24–25, 2018
Palazzo dei Congressi, Lugano, Switzerland
http://ssns2018.congress-imk.ch
Abstract book
PD Dr. med. Oliver Hausmann, Lucerne
Prof. Dr. med. Luca Remonda, Aarau
Prof. Dr. med. Michael Reinert, Lugano
PD Dr. med. Alessandro Cianfoni, Lugano
Prof. Dr. med. Jürgen Beck, Bern
PD Dr. med. Philippe Bijlenga, Geneva
PD Dr. med. Maria Blatow, Basel
PD Dr. med. Oliver Bozinov, Zurich
Prof. Dr. med. Raphael Guzman, Basel
Prof. Dr. med. Karl-Olof Lövblad, Geneva
Prof. Dr. med. Isabel Wanke, Zurich
Free Communications
O06 3D high-resolution post-contrast imaging at 3 T for the delineation of enhancing brain tumours: A comparison of MPRAGE with SPACE and VIBE techniques
L Danieli; D Distefano; E Prodi; E Ventura; GC Riccitelli; M Reinert; A Kaelin; A Cianfoni; E Pravatà
Neurocentro della Svizzera Italiana
Aims:
To prospectively investigate the differences between the Magnetization-Prepared-Rapid-Gradient-Echo (MPRAGE) 3D-post-contrast T1-weighted technique (1) recommended by the modified RANO criteria (2), and two other available techniques (Sampling-Perfection-with-Application-optimized-Contrasts-using-different-flip-angle-Evolutions (SPACE) (3) and Volumetric-Interpolated-Brain-Examination (VIBE) (4)), in the assessment of contrast-to-noise ratio (CNR), total volume (TV) and margins extent delineation (MED) of brain primitive tumors (pT) and metastases, potentially amenable to surgical and/or conformal radiotherapy treatment.
Methods:
Fifty-four contrast-enhancing lesions (38 pT and 16 metastases) were detected in 37 patients using 3 T MRI with 1-mm MPRAGE, VIBE and SPACE sequences acquired 5 min after 0.1 ml/kg administration of gadobutrol, in random order. Lesions CNR and TV segmentation were performed by an experienced neuroradiologist using a validated semi-automated tool (SmartBrush, Brainlab) followed by manual refinement. For each combination of sequence pairs, MED mismatch was quantified using subtraction volumetric maps of the segmented lesions. Friedman repeated measures and paired samples Wilcoxon non-parametric tests were used to investigate between-sequences discrepancies in CNR, TV and MED subtraction volumes.
Results:
In either pT or metastases, CNR was significantly higher in both SPACE and VIBE compared to MPRAGE (p < 0.001 and p = 0.001, respectively). Larger TVs were obtained with SPACE compared to MPRAGE in both pT (p = 0.007) and metastases (p = 0.003). Discrepancy in MED was also found, with SPACE significantly exceeding MPRAGE in both pT and metastases margins extent (p = 0.008 and 0.01, respectively).
Conclusion:
We found technique-related differences in crucial parameters for brain-enhancing pT and metastases delineation, when comparing MPRAGE to SPACE (CNR, TV and MED) and to VIBE (CNR only). These findings may be relevant for treatment planning and response assessment.
References
Brant-Zawadzki M, et al. Radiology 1992;
Ellingson BM, et al. Neurotherapeutics 2017;
Kato Y, et al. AJNR Am J Neuroradiol 2009;
Wetzel SG, et al. AJNR Am J Neuroradiol 2002;
O13 Altered cerebral blood flow before and after 4 weeks of neurostimulation in patients with episodic migraine
L Michels1; J Aschmann1; F Riederer2; A Gantenbein3; J Schoenen4; P Sandor5
1Universitätsspital Zürich
2Karl Landsteiner Institute
3University of Zurich
4University Hospital of Liège
5University of Zurich
Altered cerebral blood flow (CBF) has been observed during migraine attacks. Transcranial direct current stimulation (tDCS) has been used in patients with episodic migraine (EM) and resulted in a reduction of migraine days compared to baseline. Yet, it is unknown abnormal CBF can be modulated by noninvasive brain stimulation. We hypothesized that CBF will be different between sham and repetitive (4 weeks) real tDCS and that neuronal reorganization should be paralleled by a reduction in migraine days. On a 3 T scanner, we examined 17 adult patients with EM by arterial spin labeling MRI using a 2-D pseudo-continuous ASL sequence at three time points (baseline, FUP1 (maximally 4 weeks after tDCS), and FUP2 (6 months after baseline)). CBF difference images were achieved by simple subtraction to minimize spurious BOLD contaminations within the CBF signal. We calculated planned contrasts (t-tests, p < 0.01, corrected) for within-group differences (baseline vs. follow-up) and between-group differences (sham vs. real tDCS). For real tDCS, anodal tDCS was applied over the occipital cortex for 4 weeks (1200 s/day). Sham tDCS contained only a low (<0.1 mA) current. Eight EMs received real tDCS and nine EMs received sham stimulation and ASL-MRI. Patients did not differ with respect to sex, age, handedness, and migraine attacks at baseline (all p > 0.05). None of the patients stopped the stimulation or had a migraine attack during stimulation. Only real tDCS leads to a significant (p < 0.05) reduction in migraine days (from 9 to 6.2). Two of the EM were migraine-free at FUP2. For real tDCS, CBF was higher at baseline compared to the FUP1 in pain-processing brain regions (e.g. insula, medial prefrontal cortex, and thalamus). Comparing sham to real tDCS (at FUP1), higher CBF was seen for sham tDCS in the medial prefrontal cortex, subgenual anterior cingulate cortex, somatosensory cortex, insula, superior parietal lobe, and cuneus. Our results indicate altered CBF in the untreated group of patients. This was paralleled by the absence of any longitudinal reduction in migraine days. In contrast, real tDCS significantly reduces migraine days in EM and lowers CBF (compared to baseline and sham, respectively) in the brain regions associated with pain processing, such as the insula and prefrontal cortex. In addition, the brain regions linked to cognitive control showed lower CBF during real tDCS versus sham tDCS.
O16 To scan or not to scan: The role of follow-up CT scanning for management of chronic subdural hematoma after neurosurgical evacuation (TOSCAN): A randomized, controlled trial
P Schucht
Inselspital, Universitätsspital Bern
Aims:
Chronic subdural hematoma has a high recurrence rate after surgery and postoperative scans often show substantial residuals, eventually leading to a higher rate of reoperation. However, the benefit of postsurgical imaging for patient outcome remains unknown. The aim of this study was to investigate the value of postoperative CT scans for outcome after surgical evacuation of chronic subdural hematoma.
Methods:
We randomly assigned 368 patients with newly diagnosed chronic subdural hematoma within 48 h after surgery to either a combined radiological and clinical follow-up (CT arm) or a clinical follow-up with scans only in case of neurological deterioration (No-CT arm). The primary outcome was the modified Rankin Scale (mRS) score at 90 days; this categorical scale measures the functional outcome, with scores ranging from 0 (no symptoms) to 6 (death).
Results:
A follow-up protocol with CT imaging did not improve the primary outcome; there was no significant between-arm difference for mRS as a categorical variable (p = 0.79) or as numerical variable (p = 0.37). The proportion of patients who survived without severe disability (mRS 0–3) was 89% in the CT arm and 93% in the No-CT arm (odds ratio 1.4, 95% confidence interval 3.72–0.82, p = 0.15). Death occurred in 12 patients in the CT arm and in 8 patients in the No-CT arm (p = 0.5). Reoperation for recurrent hematomas was performed in 59 patients in the CT arm and in 39 patients in the No-CT arm (p = 0.055). Complications were seen in 26 patients in the CT arm and in 19 patients in the No-CT arm (p = 0.34).
Conclusion:
Routinely scheduled CT scans after neurosurgical evacuation of chronic subdural hematoma have no benefit on outcome.
Posters
P39 Loss of mural cells leads to impaired thrombus remodelling and prolonged aneurysm cicatrisation in a rabbit arterial sidewall aneurysm model
F Strange1; BE Grüter1; M von Gunten2; HR Widmer3; J Berberat1; L Remonda1; J Fandino1; D Coluccia1; S Marbacher1
1Kantonsspital Aarau
2Institute of Pathology Laenggasse
3Bern University Hospital (Inselspital)
Aims:
Previous studies have demonstrated that ruptured aneurysms show a significant cell loss in the vessel wall when compared to unruptured aneurysms. Decellularized aneurysms have been confirmed to be prone to growth and rupture, when compared with vital aneurysms in a rat model. The exact mechanism of thrombus and vessel wall interaction and aneurysm growth is yet insufficiently understood. The authors therefore investigated this in a rabbit arterial sidewall aneurysm model.
Methods:
Sidewall aneurysms were created bilaterally on the carotid artery of New Zealand white rabbits. Aneurysms vessel walls were vital (n = 6) or decellularized (n = 12), of which six animals additionally received acetylsalicylic acid (ASA) in the drinking water. For decellularization, vessel pouches from a donor animal were incubated in 1% sodium dodecyl sulfate for 6 h to destroy cells of the vessel wall but not the extracellular matrix. Follow-up time was 1 month. Aneurysm growth was monitored with a transcutaneous ultrasound on a weekly basis and all animals received an MR angiography prior to euthanasia. Histological analyses of the aneurysms were used to assess the role of periadventitial environment, aneurysm wall and thrombus remodelling.
Results:
During the study period, no aneurysms were ruptured. All aneurysms showed a significant decrease in volume, more pronounced in vital aneurysms as compared to decellularized aneurysms (p = 0.045). Histologically, decellularized aneurysms demonstrated a tendency towards a higher wall inflammation when compared to vital aneurysms. The administration of ASA was associated with a non-significant trend towards fewer wall haematoma and reduced wall inflammation.
Conclusion:
Although aneurysm growth and rupture did not occur, the absence of mural cells led to impaired intraluminal thrombus organization and neointima formation in the rabbit arterial sidewall aneurysm model. The excessive inflammation in decellularized aneurysms may partially be attenuated by the administration of ASA and therefore potentially support aneurysm healing.
P42 Measuring the impact of delayed cerebral ischaemia on neuropsychological outcome after aneurysmal subarachnoid haemorrhage: Protocol of a Swiss nationwide observational study (MoCA – DCI study)
MN Stienen1; C Fung2; P Bijlenga3; D Zumofen4; R Maduri5; T Robert6; MA Seule7; S Marbacher8; E Keller1; L Regli1
1Universitätsspital Zürich
2Inselspital, Universitätsspital Bern
3Hôpitaux Universitaires de Geneve (HUG)
4Universitätsspital Basel
5Centre Hospitalier Universitaire Vaudois and University of Lausanne
6Ente Ospedaliero Cantonale
7Kantonsspital St. Gallen
8Kantonsspital Aarau
Aims:
Delayed cerebral ischaemia (DCI) could be identified as an important predictor of neuropsychological impairment following aneurysmal subarachnoid haemorrhage (aSAH) in single-centre studies. All previous studies lacked a baseline neuropsychological assessment before DCI onset. Neuropsychological evaluation of acutely ill patients is often applied in a busy intensive care unit (ICU), where distraction represents a bias to the obtained results. The objective of this study is to evaluate the relationship between DCI and neuropsychological outcome after aSAH by comparing the Montreal Cognitive Assessment (MoCA) results in aSAH patients with and without DCI immediately after the DCI-period and at 3 months with the baseline examination before the DCI-period (part 1). A further objective is to determine the reliability of the MoCA, when applied in an ICU setting (part 2).
Methods:
This is a prospective, multicentre, observational study performed at all Swiss neurovascular centres treating patients with aSAH. For part 1, a total number of n = 240 consecutively recruited aSAH patients and for part 2 n = 50 patients with acute brain injury are recruited. Outcome measures for part 1 are the MoCA, the modified Rankin Scale (mRS), EuroQol (EQ5D) and home time. Part 2 of the study applies reliability measures for the MoCA.
Results:
The institutional review board (Kantonale Ethikkommission Zürich (KEK-ZH)) approved this study on 4 July 2017 under case number 2017-00103. After completion of the study, the results will be offered to an international scientific journal for peer-reviewed publication. This study determines the exact impact of DCI on the neuropsychological outcome after aSAH, unbiased by confounding factors such as early brain injury or patient-specific characteristics. The study provides unique insights into the neuropsychological state of patients in the early period after aSAH. In this presentation, focus is laid on the methods of this Swiss collaborative multicentre study, but the current state of recruitment and some illustrative patient examples are given.
Conclusion:
This study is an example of how collaborative studies in clinical neuroscience can be conducted, using well-established structures such as the Swiss SOS study group. The study is currently on track and recruitment is ongoing.
Trial registration: The study is registered with the http://ClinicalTrials.gov identifier: NCT03032471.
P50 Dose reduction and image quality in gridless spinal angiography: A prospective study in 53 patients
A El Mekabaty1; E Orru2; D San Millán3; P Gailloud2
1Inselspital, Universitätsspital Bern
2The Johns Hopkins Hospital
3Hôpital du Valais (RSV)
Purpose:
To test the hypothesis that removal of the anti-scatter grid (ASG) significantly lowers the dose in spinal DSA (SpDSA) while maintaining diagnostic image quality.
Materials and methods:
53 adult patients undergoing a full or partial SpDSA were studied. SpDSAs were performed entirely with or without the ASG with an additional DSA sequence with the ASG repositioned or removed (depending on how the exam was performed) documenting the key finding of the. Data on exposure were analyzed in order to determine the reduction in dose and if it was BMI dependent. Two interventionalists were independently asked to blindly compare the sets of two images of the key finding in the same patient and to: (1) rate image quality; (2) categorize the image finding in a category between “normal anatomy”, “vascular tumor,” or “vascular malformation”; and (3) determine if the image had been obtained with or without the ASG.
Results:
Removing the ASG reduces dose of approximately 30% (p < 0.001) in a BMI-independent fashion. Both readers evaluated 100% of the images as good or excellent diagnostic and correctly categorized the finding in 95% of the cases, while being unable to consistently determine if the images had been obtained with or without the ASG.
Conclusion:
Removing the ASG during SpDSAs can significantly lower the dose to the patient and the operators while maintaining sufficient diagnostic quality of the images. Spinal vessels are among the smallest in the body: This dose reduction strategy could find broad application in more commonly performed abdominal interventional procedures.
P51 Clinical and radiological outcomes in minimally invasive transforaminal lumbar interbody fusion with expandable cages
A Jilch1; D Giunchi2; P Scarone2
1Ente Ospedaliero Cantonale
2Ospedale Regionale di Lugano
Aims:
Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) with oblique cage is widely used for treatment of degenerative disc disease, foraminal stenosis and spondylolisthesis. Main problems related to this approach are secondary mobilization of interbody cages and quality of interbody fusion. Use of expandable technology could allow to solve these problems, but data from literature concerning expandable cages are scarce.
The aim of this study was to retrospectively analyze clinical and radiographic outcomes in a consecutive series of patients who have undergone MIS TLIF with an expandable titanium cage with minimum 1 year follow-up.
Methods:
Patient population and study design: We retrospectively analyzed a series of 17 patients (18 to 80 years), operated between 2015 and 2016. Demographic and clinical data, clinical outcome scores, device-related complications as well as radiographic and anatomic features (disc height, foraminal height, grade of foraminal stenosis, fusion) were recorded. We did not use expandable cages in patients with scoliosis, spinal tumors, and osteoporosis.
Results:
The leading symptoms (64.70%) were the combination of lumbago and radiculopathy. The underlying pathologic conditions were mostly foraminal stenosis and degenerative or isthmic lytic spondylolisthesis (41.17%). Mean hospital stay was 7.76 days ±3.01. Three medical complications were recorded perioperatively, not related to surgical approach. Long-term complications during follow-up included persistent neuropathic pain in the lower limbs in 1 patient. No patient needed reoperation and no patient showed mobilization of the cage during follow-up. Mean follow-up was 12.4 months. Mean back and leg pain intensity before surgery was graded 8.8 points (±1.03) and 5.1 points (±2.85) on the VAS, and improved postoperatively to 3.5 points (±2.99) and 2.1 points (±2.69) respectively. The mean ODI was 55.99% (±15.77) preoperatively and 10.21% (±11.68) postoperatively. The majority of patients (11; 64.70%) showed complete fusion and 6 patients (35.29%) a partial fusion. Subsidence of the cage occurred in 4 patients (23.52%).
Conclusions:
MS TLIF surgery with a titanium expandable lumbar fusion device led to favorable clinical and radiographic outcome with durable restoration of the disk and foraminal height without major neurological or device-related complications. Use of expandable cages did not improve fusion rate in this series. Incidence of cage subsidence was significant, and comparable to recently reported data from other series. However, this was not associated with worse clinical outcome.
We plan to perform a prospective randomized study on clinical and radiographic parameters in patients undergoing MIS TLIF surgery with expandable versus static cages as well as on the cost-effectiveness.
We plan to perform a prospective randomized study on clinical and radiographic parameters in patients undergoing MIS TLIF surgery with expandable versus static cages as well as on cost-effectiveness.
References
Alimi M, et al. Global Spine J 2015;
Carreon LY, et al. Spine 2007;
Habib A, et al. Minimally Invasive Surg 2012;
Hawasli AH, et al. Neurosurg Focus 2017;
Kim CW, et al. World Neurosurg 2016;
Kroppenstedt S, et al. Spine 2008;
Lee S, et al. AJR 2010;
Nemoto O, et al. Eur Spine J 2014;
Rickert M, et al. Bone Joint J 2017;
Schimmel JJP, et al. Clin Spine Surg 2016;
Shah RR, et al. Eur Spine J 2003;
Steffee AD, et al. Spine 1993;
Yang Y, et al. Int J Clin Exp Med 2015;
P52 Stroke and stroke mimics in the acute setting: Role of multimodal CT
E Prodi1; L Danieli1; E Pravatà1; L Roccatagliata2; C Manno1; CW Cereda1; C Staedler1; A Cianfoni1
1Neurocenter of Southern Switzerland, Ospedale Regionale di Lugano
2Università degli Studi di Genova, Dipartimento di Scienze della Salute
Aim:
Stroke can be mimicked by nonvascular conditions. Due to emphasis on rapid admission and treatment of acute ischemic stroke patients, it is crucial to identify these conditions to avoid unnecessary treatments and potential complications. We reviewed the prevalence of stroke mimic conditions at our center and investigated the performance of the multimodal-computed tomography (CT) protocol (unenhanced and contrast-enhanced brain CT, CT angiography, and CT perfusion) to discriminate stroke mimics from ischemic stroke.
Methods:
We retrospectively searched from our radiology database and selected all imaging studies performed for clinical suspicion of acute ischemic stroke between January 2015 and December 2016. Patients with a multimodal CT protocol at admission and at least one follow-up imaging study (brain CT or MR) were included. We compared the results of the multimodal CT protocol with the final clinical diagnosis at discharge.
Results:
Four hundred twenty-four patients were included. In 94 cases, a stroke mimic condition was eventually diagnosed, with a prevalence of stroke mimics of 23% including 30 seizures, 11 migraines with aura attack, 10 functional disorders, 8 infections, 7 brain tumors, 5 peripheral vertigo, 4 metabolic causes, 3 syncope, 2 transient global amnesia, 1 hypoglycemia, 1 subdural hematoma, 1 cervical epidural hematoma, 1 dural fistula, and 10 nonvascular undetermined causes. Multimodal-CT sensitivity, specificity, and accuracy were 22%/99%/82% overall and 33%/99%/89% when excluding a priori CT-undetectable stroke mimic conditions (functional disorders, syncope, and peripheral vertigo). Multimodal CT revealed 12/30 peri-ictal changes, 7/7 brain tumors, 1/1 dural fistula, and 1/1 subdural hematoma. CT perfusion played a key role in the detection of seizure-related stroke mimic conditions, where brain CT and CT angiography are typically silent.
Five of 12 seizures and 6/7 tumors showed a hyperperfusion pattern (increased cerebral blood volume and flow ± reduced mean transit time), while 7/12 seizures and 1/7 tumors showed a hypoperfusion pattern (increased mean transit time ± reduced cerebral blood volume and flow).
Conclusions:
Multimodal CT demonstrated low sensitivity but rather high specificity in the diagnosis of stroke mimics in the acute setting. Multimodal CT’s ability to identify stroke mimics may represent an asset in the diagnostic management of patients with suspected stroke.
References
Merino JG, et al. J Stroke Cerebrovasc Dis 2013;
Tsivgoulis G, et al. Stroke 2015;
P53 Multi-vessel occlusion in patients subjected to thrombectomy: Prevalence, associated factors and clinical implications
J Kaesmacher; P Mosimann; U Fischer; J Gralla
University Hospital Bern (Inselspital)
Background:
Patients with embolic large-vessel occlusion may present with additional coincidental acute occlusions within or distant from the involved territory, referred to as multi-vessel occlusion (MVO).
Methods:
Image data of consecutive endovascular candidates (n = 720) with direct access to angiography were extracted from a prospective registry. Prevalence of MVO was assessed with multimodal MRI/CT and confirmed by intra-arterial angiography. Explorative analysis and clinical relevance were evaluated using multivariate logistic regression.
Results:
MVO was present in 10.7% of patients (95% CI 6.4–13.0%). Two, three, and four concomitant occlusions were found in 80.5%, 16.9%, and 2.6% of MVO cases, respectively. Detection rate on the initial radiological report was 54.5%. Downstream MVO was present in around one-third of MVO (n = 27/77, 35.1%), while all other MVO (n = 50/77, 64.9%) occurred in different territories. Independent factors related to MVO were statin treatment (aOR 0.477, 95% CI 0.276–0.827), higher systolic blood pressure (aOR per mmHg increase 1.014, 95% CI 1.005–1.023) and primary occlusion site M2 (aOR 1.870, 95% CI 1.103–3.170). MVO was related to lower rates of successful reperfusion (aOR 0.549, 95% CI 0.316–0.953) and poorer functional outcome (aOR 0.456, 95% CI 0.224–0.930).
Conclusion:
Every tenth patient subjected to angiography for endovascular stroke treatment experienced MVO in our series and only half were prospectively identified on pre-interventional diagnostic imaging. Patients with MVO had higher baseline systolic blood pressure and were less often medicated with statins, an observation that warrants external validation and evaluation regarding causality. Occurrence of MVO has implication for treatment decisions, negatively affects endovascular treatment success and is predictive of worse clinical outcome.
P54 T1, T2, and T2* relaxivity changes in brain white and gray matter in anorexic patients
J Boto1; A Regnaud1; G Georgios1; T Kober2; L Karl-Olof1; F Lazeyras1; NC Askin1; MI Vargas1
1Hôpitaux Universitaires de Genève
2Advanced Clinical Imaging Technology
Aim:
Anorexic related morphological brain changes have been demonstrated in the literature. The aim of this study is to uncover further brain abnormalities in T1, T2, and T2* relation times of white and gray matter in anorexic patients.
Methods:
Subjects are 35 anorexic females (mean age, 25.7 years; range, 16.2–48.7 years) with BMI inferior to 18.5 kg/m2 (mean BMI, 14.4 kg/m2; range, 10.0–18.4 kg/m2) presenting consecutively for brain MR between August 2014 and February 2018. Controls include 15 healthy females (mean age, 27.7 years; range, 22.4–34.7 years; mean BMI, 21.0 kg/m2; range, 18.4–27.3 kg/m2). Automated brain segmentation will be performed on Magnetization-Prepared 2 Rapid-Gradient-Echo (MP2RAGE) MR images. The masks obtained will then be transferred to the specific T1, T2, and T2* mapping sequences in order to quantify the respective relaxation times of total brain and different brain structures in anorexics and controls.
Results:
Preliminary results based on the hand-drawn elipsoid-shaped regions of interest (ROIs) in the white matter of the centrum semiovale revealed significantly lower T1 relaxation times in the anorexic group compared to age and sex matched controls (p = 0.028). T2 and T2* relaxation times did not show a significant difference between the two groups. We expect that the application of the automated segmentation method will add additional accuracy and allow differences in the relaxation times of whole brain, and different brain structures and regions between anorexics and controls to become more apparent.
Conclusions:
Preliminary results show significantly lower T1 relaxation times in the brain white matter of anorexics compared to normal controls, possibly reflecting starvation-driven myelin depletion. We expect that this first attempt at performing T1, T2, and T2* brain mapping in anorexics might open the door to possible treatment options and motivate further longitudinal studies to confirm the resolution of these abnormalities.
P55 Imaging finding of spinal tumor and main differential diagnosis
L Etienne; J Boto; A Regnaud; C Santarosa; K Lövblad; MI Vargas
Hopitaux Universitaires Genève
Aim:
The aim of this educational poster is to illustrate the most frequent spinal tumors and their main differential diagnosis, pearls, and pitfalls.
Methods:
We have conducted a search in our PACS over the last 10 years using the following search terms: tumor, spondylodiskitis, astrocytoma, ependymoma, cavernoma, meningioma. We subsequently selected the most representative cases of spinal tumors and tumor mimics (MRI and CT). The MRI imaging protocols comprise both standard morphological sequences (T1WI, T2WI, STIR) and advanced techniques (DTI, tractography, perfusion). Lesions were classified according to the anatomical location (intramedullary, intradural extramedullary, extradural).
Results:
This poster illustrates different benign and malignant spinal tumors as well as the main differential diagnosis. The pathological entities shown are astrocytoma (OMS grade I and II), glioblastoma, ependymoma, myxopapillary ependymoma, hemangiomablastoma, cavernoma, meningioma, neurofibroma, schwannoma, metastasis, lymphoma, spondylodiskitis, lipoma of the filum terminale, arthro-synovial cyst, ventriculus terminalis, and diskal hernia.
A section of the poster will be dedicated to showing artifacts on MRI that could mimic pathology.
Conclusion:
MRI is the method of choice for the characterization of spinal tumors. Advanced techniques are invaluable tools in achieving a high degree of accuracy in presurgical planning and also to narrow the differential diagnosis of spinal lesions.
P56 Feasibility of GRASP in clinical routine detection of pituitary microadenomas
N Hainc1; C Stippich1; J Reinhardt2; B Stieltjes3; M Blatow1; L Mariani3; A Bink3
1University Hospital of Zurich
2University Hospital of Zurich, University of Basel Hospital
3University of Basel Hospital
Aims:
To demonstrate the clinical feasibility of a novel MRI pulse sequence, golden-angle radial sparse parallel MRI (GRASP) through comparison to the current imaging technique, dynamic contrast–enhanced (DCE) imaging in terms of image quality and lesion depiction in the detection of microlesions (microadenomas and cysts) of the pituitary gland.
Methods:
Sixteen patients (11 microadenomas, 5 cysts) underwent two MRI examinations (Siemens 1.5 T and 3 T) on separate dates, one using standard DCE (resolution 0.9 × 0.9 mm2, slice thickness 2 mm, temporal resolution of 30 s) and the other using GRASP (spatial resolution 1.0 × 1.0 × 1.0 mm3 isotropic voxels, temporal resolution of 4 s). Two neuroradiologists separately recorded measures of image quality (scale 1–5, 5 = best), lesion size and contrast arrival times in terms of first and optimal lesion conspicuity.
Results:
In qualitiative analysis, there were no significant differences in terms of average visual image sharpness (DCE 3.9–0.9, GRASP 3.9–0.9, p > 0.05) or visual contrast scores (DCE 4.1–1.2, GRASP 4.4–0.8, p > 0.05). Pearson’s correlation coefficients for interreader lesion measurements (width and height, mm) ranged from substantial to almost perfect agreement (r = 0.73–0.88). Analysis of contrast arrival times revealed an average lesion first-conspicuity time of 60.7–16.7 s for DCE compared to 50.2–10.3 s for GRASP with a difference of 10.5–16.2 s (p = 0.023). Lesion best-conspicuity was 91.9–39.5 s for DCE compared to 77.4–23.6 s for GRASP (p > 0.05).
Conclusions:
The significant difference in average contrast arrival times for lesion first-conspicuity between DCE and GRASP shows the advantage of continuous data acquisition with GRASP. Even though the in-plane resolution for the isotropic GRASP voxels was less than the anisotropic DCE voxels, no significant difference in visual assessment was found on GRASP images. For microadenoma detection, GRASP is feasible in clinical routine, delivers visually similar results and detects microadenoma at least as reliable as DCE. Taking into account the known robustness against motion artefacts and the advantage of earlier detection of microadenomas with GRASP, this technique might offer better diagnostic yield than DCE which is to be proved in larger cohorts.
P57 Fully automatic volumetry in glioblastoma
A Bink1; E Nijhuis1; D Germanier1; S Leu1; S Schädelin1; A De Vere-Tyndall2; L Mariani1; C Stippich3
1University Hospital Basel
2University Hospital Zurich and University of Zurich
3University Hospital Zurich
Aims:
Subcompartment analysis has shown prognostic value in imaging of gliomas. While manual volumetry is time-consuming and not implemented in clinical routine, newer advances in automatic software tools made fully automatic analysis of glioma subcompartments available.
Methods:
We performed a qualitative and quantitative comparison of fully automatic and visual volumetry in patients with glioblastoma of the subcompartment necrosis, non-contrast-enhancing tumor (NCET), contrast-enhancing tumor (CET), edema, total tumor volume (TOTAL) without edema, and TOTAL.
Preoperative MRIs of 55 patients with glioblastoma were analyzed fully automatically and visually. Quality of automatic analysis was categorized by four raters as good, partially failed, and failed. Statistical analysis was performed by Pearson correlation.
Results:
Quality analysis showed good segmentations in 32 patients, partially failed segmentations were found in 19 patients, and 4 failed segmentations (2 × movement artifacts, 2 × failed scull stripping).
The correlation analysis of fully automatic and visual volumetry resulted in necrosis ρ 0.37 (p = 0.05); NCET ρ 0.5 (p < 0.01); CET ρ 0.86 (<0.01); edema ρ 0.83 (<0.01); TOTAL ρ 0.83 (<0.01); TOTAL with edema ρ 0.94 (<0.01). The time needed for automatic evaluation was 5 min. Depending on the tumor complexity, visual assessment took between 10 min and 30 min.
Conclusion:
Although fully automatic segmentation performed well in unexcelled time, we strongly recommend checking results generated by automatic segmentation by an experienced neuroradiologist due to possible outliers.
P58 Diffusion imaging of treated and untreated meningiomas: A follow-up study
L Schwyzer; C Braun; J Fandino; U Roelcke; L Remonda; J Berberat
Kantonsspital Aarau AG
Introduction:
A noninvasive method to predict the treatment outcome of meningiomas would be desirable to improve tumor management. Previous studies have shown that pretreatment apparent diffusion coefficient (ADC) values can predict treatment response in brain tumors. To analyze whether intra-tumoral ADC values change due to treatment over time, untreated and treated meningiomas were compared.
Methods:
MRI examinations of 64 patients with suspected or histologically confirmed meningiomas were retrospectively reviewed. This series included 28 untreated patients and 36 treated (n = 10 partially resected; n = 26 radiosurgery) patients. The follow-up time period ranged between 1 year and 10 years. Comparing ADC with T1-weighted sequences, a region of interest (ROI) was placed within tumor margins avoiding the surrounding normal brain. An ROI was then set on the adjacent slice above and below, if the tumor was large enough using the PMOD software. The ADC values of these three ROIs were then averaged and statistically compared using SPSS Statistics v24.
Results:
Baseline ADC values before treatment were similar in treated and untreated meningiomas. The mean ADC values, ADC10%min and ADC90%max within the different groups, did not show significant changes during the follow-up in untreated (over a 10-year period: 0.87 ± 0.05 ×10−3 mm2/s), partially resected (over a 10-year period: 1.01 ± 0.07 × 10−3 mm2/s), and radiosurgically treated (over a 4-year period: 1.02 ± 0.12 × 10−3 mm2/s) groups. However, a significant difference was observed between the mean ADC and ADC90%max values of untreated and partially resected (p < 0.0001) and, respectively, radiosurgically treated (p < 0.0001) meningiomas. Also, ADC10%min revealed statistically significant difference between untreated and radiosurgery groups (p < 0.05) as well as between untreated and partially resected meningiomas (p < 0.001).
Conclusion:
ADC values in conservatively managed meningiomas remain stable during the follow-up. However, treated meningiomas reveal a significant change of the mean ADC values over time, suggesting that ADC may reflect a change in the biological behavior of the tumor.
P59 Cinematic rendering in neuroradiology: A novel 3-D rendering tool for computed tomography and magnetic resonance imaging
S Winklhofer; A Kobe; A Valavanis; H Alkadhi; Z Kulcsar
University Hospital Zurich
Aims:
Cinematic rendering (CR) is a recently introduced technique which is based on an advanced three-dimensional (3-D) rendering algorithm allowing for a more photorealistic visualization of lesions compared to conventional volume rendering techniques (VRT). The purpose of this study is to demonstrate the feasibility of CR for neuroradiological applications in computed tomography and magnetic resonance imaging data sets.
Methods:
Intracranial lesions as well as lesions of the head and neck were identified in which an application of cinematic rendering might be possible. CR images were reconstructed using a prototype rendering software.
Results:
Lesions with a high contrast (such as iodine- or gadolinium-containing structures as well as bony structures in CT) are displayed in CR reconstructed data sets. Image examples are given for common intracranial lesions and lesions of the head and neck region such as aneurysms, meningiomas, hemangiopericytomas, intracranial arteriovenous malformations, arteriovenous fistulas, complex skull fractures, carotid paragangliomas, and vascular malformations of the head and neck.
Conclusion:
Cinematic rendering allows for the generation of the photorealistic 3-D images of selected high-vascularized intracranial and head and neck lesions as well as of bony structures. This technique might be a helpful tool for a better understanding and for preoperative planning of complex pathologies. Additional research is required to assess the added value of CR compared to two-dimensional images and conventional 3-D VRT.
P60 Spinal MR angiography for the reliable identification of the artery of Adamkiewicz and its tributary arteries
JK Richter; AA Peters; DV Bower; R Laqua; M Ith; SY Kim; B Jung; JT Heverhagen; H von Tengg-Kobligk; F Mosler
Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
Aims:
This educational poster focuses on the image acquisition, identification, and precise reporting of the main feeder of the anterior spinal artery in the thoraco-lumbar segments.
It covers four major areas, making use of clinical images to convey the benefits of high-resolution MR imaging at 3 T in the imaging of spinal arteries in free-breathing patients in day-to-day routine. The anatomy and function of the artery of Adamkiewicz (also known as A. radicularis magna or AKA) as well as the clinical consequences from an occlusion are illustrated and explained. The standard clinical situations are pointed out in which the identification of the AKA and of the level of its supply from the aorta is imperative. The technical basis of the MRA (DixonVIBE) and the know-how needed to implement it and plan the exam are explained, in no more detail than is relevant to the clinical radiologist. How to post-process the imaging data in order to achieve maximum identification rates of both AKA and its supplying arteries as well as for providing the clinicians with the best visualization of the imaging result for the referring clinician.
Methods:
Images were acquired on a 3 T scanner using two 30-channel body coils. Imaging protocols include a T1 weighted, steady-state radial VIBE MRA with fat saturation as well as a first-pass MRA. Dedicated post-processing is shown, including curved coronal MPR and MIP reformations to provide the clinician with a better visualization.
Results:
High-resolution MRA of the spinal arteries achieves excellent image quality using standard clinical equipment and dedicated post-processing done by a resident.
Conclusion:
Advantages of MRA over micro-invasive intra-arterial catheter-based angiography become evident with proper image acquisition, processing as well as focused reporting.
At our institution, we have developed protocols for high-resolution 3 T spinal MRAs (both steady state and first pass) for patients with aortic aneurysms as a preoperative exam to help the cardiovascular surgeons prioritize which intercostal arteries are crucial for the perfusion of the anterior spinal artery and need to be inserted into the aortic graft. Spinal MRA has replaced CTA and DSA as the modality of choice for preoperative imaging of the spinal arterial supply in patients with aortic aneurysms at our institution.
P61 Comparison of new-generation double-layer micromesh carotid stent system versus carotid self-expanding hybrid stent system in symptomatic carotid artery stenosis
P Gruber; T Kahles; J Berberat; J Anon; M Diepers; K Nedeltchev; L Remonda
Kantonsspital Aarau AG
Objective:
Carotid artery stenosis is a relevant cause of ischemic stroke. Carotid artery stenting is an emerging alternative treatment option to surgical carotid endarterectomy. Several carotid stent systems with different stent designs are available. CASPER (MicroVention, Inc., USA)—a double-layer micromesh carotid stent system designed to prevent periprocedural embolic release—belongs to the latest generation of carotid stent system. The aim of this study was to assess the efficacy and safety of CASPER compared to a carotid self-expending hybrid stent system (Cristallo; Invatec Cristallo Ideal, Medtronic, USA) in symptomatic carotid artery stenosis (sCS).
Method:
A single-center, open-label, retrospective cohort study of 57 consecutive patients with proven sCS between January 2014 and August 2017 executed at a tertiary stroke center in Switzerland. Outcome measures were (i) good clinical outcome at 90 days (mRS 0–2), (ii) periprocedural complications and ischemic events, (iii) reocclusion rate, and (iv) mortality within 30 days.
Results:
Twenty-two patients (23% women, median age 75 years (interquartile range (IQR) 71–80) were treated with CASPER, 35 patients (29% women, median age 71 years (IQR 63–76)) with Cristallo. In both groups, pretreatment carotid stenosis had a similar median NASCET score of 80%. Successful deployment was achieved in all cases without technical failure and similar reocclusion rates and mortality rate within 30 days. Clinical outcome was similarly beneficial in both groups. In the Cristallo group, periprocedural ischemic event was insignificantly higher (3 vs. 0; p = 0.16).
Conclusion:
CASPER and Cristallo demonstrate to be similarly effective and safe in symptomatic carotid artery stenosis.
P62 Preliminary experience with a novel drug coating balloon catheter for symptomatic intracranial high-grade stenosis
P Gruber; T Kahles; J Berberat; M Hlavica; J Anon; M Diepers; K Nedeltchev; L Remonda
Kantonsspital Aarau AG
Objective:
Intracranial arteriosclerotic disease is a relevant cause of ischemic stroke worldwide. Despite best medical treatment, the reoccurrence rate is high. Because of the discouraging SAMMPRIS trial, neurovascular treatment remained a second-line therapy. Since, there has been tremendous advancement in device technology. SeQuent Please NEO (B.Braun, Melsungen, Germany) is a novel polymer-free, drug-coated (paclitaxel/iopromide) balloon (DCB) primarily designed for cardiology. Because of its high flexibility and pushability, it seems to be suitable also for intracranial use. Furthermore, it offers a sustained antiproliferative effect and natural vessel restoration. The aim of this case series was to assess the feasibility and safety of SeQuent Please NEO in symptomatic intracranial high-grade stenosis.
Method:
A single-center case series of 12 patients with symptomatic intracranial high-grade stenosis between September 2016 and January 2018 treated with SeQeunt Please NEO DCB executed at a tertiary stroke center in Switzerland.
Results:
Twelve patients (100% men, median age 73 years (interquartile range (IQR) 70–77) were treated with SeQuent Please NEO. Median pretreatment carotid stenosis grade was 78% (IQR 75–80) with two mid-basilar, five internal cerebral artery, and five vertebral artery lesions. Median posttreatment stenosis grade was 50% (IQR 45–52). Successful angioplasty was achieved in all cases without technical failure and no periprocedural reocclusion rates and no mortality rate at follow-up.
Conclusion:
SeQuent Please NEO CDB demonstrates to be feasible and safe in symptomatic intracranial high-grade stenosis. Therefore, it might constitute a promissing alternative to medical treatment.
Reference
Chimowitz MI, et al. NEJM 2011;