KS02.7.A Impact of FET PET on multidisciplinary neurooncological tumor board decisions in patients with brain tumors

Background

Following neurooncological treatment of brain tumors, neurooncologists are often confronted with equivocal MRI findings (e.g., treatment-related changes such as pseudoprogression, non-measurable contrast-enhancing lesions, T2/FLAIR signal alterations, pseudoresponse). Especially in Europe, amino-acid PET is increasingly integrated into multidisciplinary neurooncological tumor boards (MNTB) to overcome these diagnostic uncertainties. We evaluated the correctness of MNTB decisions, in which amino acid PET findings were taken into account.

Material and Methods

In a single-university center study, we retrospectively evaluated 182 MNTB decisions of 154 patients with histomolecularly defined WHO grade 3 or 4 gliomas (n=123), including glioblastoma (n=80), anaplastic glioma (n=42), and gliosarcoma (n=1), or brain metastases (n=31) secondary to lung cancer, melanoma, breast cancer, or colorectal cancer presenting equivocal MRI findings following anticancer treatment. All patients underwent O-(2-[18F]-fluoroethyl)-L-tyrosine (FET) PET imaging as an adjunct for decision-making. Additionally, the patients’ clinical status, pretreatment, and conventional MRI findings were considered for decision-making. The presence of neoplastic tissue was considered if the mean FET uptake as assessed by tumor-to-brain ratios was > 2.0. MNTB decisions were validated using the neuropathological result in 42% (n=77) or clinicoradiologically in 58% (n=105). The diagnostic performance of MTNB decisions was evaluated using 2x2 contingency tables.

Results

The validation of all 182 MNTB recommendations, which integrated FET PET in the decision-making process, were correct in 95% (sensitivity, 97%; specificity, 75%; positive predictive value, 96%). Due to tumor progression, MNTB recommendations prompted a treatment change in 88% (n=160 of 182 decisions). When FET PET findings suggested progressive disease (n=157), MNTB decisions were correct in 96% (positive predictive value, 97%). In 22 MNTB decisions with the recommendation to continue the current treatment regimen, 82% were correctly identified as treatment-related changes.

Conclusion

FET PET seems to have a significant impact on MNTB decisions. A prospective evaluation of MNTB decisions with and without the integration of FET PET is warranted to define the added value of FET PET.

P15.05.A Prediction of response to lomustine-based chemotherapy in glioma patients at relapse using MRI and FET PET

Background

This study evaluates O-(2-[18F]fluoroethyl)-L-tyrosine (FET) PET and contrast-enhanced MRI for early response assessment in glioma patients at relapse treated with lomustine-based chemotherapy.

Material and Methods

Thirty-seven adult patients with WHO CNS Grade 3 or 4 gliomas at relapse (glioblastoma, 70%; median number of relapses, 1) were retrospectively identified. Besides MRI, serial FET PET scans were performed at baseline and early after chemotherapy initiation (median number of cycles, 2). Mean and maximum tumor-to-brain ratios (TBR), metabolic tumor volumes (MTV), the occurrence of distant hotspots with a mean TBR > 1.6 at follow-up, and dynamic parameters (i.e., time-to-peak and slope) were derived from all FET PET scans. Threshold values of PET parameters were defined using receiver operating characteristic analyses to predict progression-free survival (PFS) of ≥6 months and overall survival (OS) of ≥12 months. MRI response assessment was based on RANO criteria. The predictive value of FET PET parameters and RANO criteria were subsequently evaluated using univariate and multivariate survival estimates.

Results

After treatment initiation, the median follow-up time was 11 months (range, 3-71 months). Maximum TBR and MTV (threshold, ≤0%) and RANO criteria predicted a significantly longer PFS (all P<0.001) and OS (all P<0.03). At follow-up FET PET imaging, the occurrence of new distant hotspots (n≥1) predicted a worse outcome, with significantly shorter PFS (P=0.001) and OS (P<0.001). Dynamic PET parameters did not predict a significantly longer PFS or OS (P>0.05). Multivariate survival analyses revealed that new distant hotspots at follow-up had the highest level of significance to predict non-response (P=0.002; hazard ratio, 5.722), independent of RANO criteria, IDH mutation status, and O6-methylguanine-DNA-methyltransferase promoter methylation.

Conclusion

FET PET seems to be a powerful tool for identifying responders to lomustine-based chemotherapy early after treatment initiation.

Treatment of Proximal Posterior Inferior Cerebellar Artery Aneurysms by Intrasaccular Flow Disruption: A Multicenter Experience

BACKGROUND AND PURPOSE

Treatment of PICA aneurysms can be technically challenging by either surgical or endovascular means. Our aim was to report our preliminary experience with intrasaccular flow disruption using the Woven EndoBridge (WEB) for the treatment of proximal PICA aneurysms.

MATERIALS AND METHODS

Sixteen PICA aneurysms treated with the WEB at 3 institutions were retrospectively reviewed. Baseline patient and aneurysm characteristics, procedural specifics, clinical outcomes, and angiographic results were evaluated.

RESULTS

All aneurysms were located at the proximal, anteromedullary segment of the PICA. Seven aneurysms were ruptured. The median aneurysm size was 3.9 mm (range, 2-12 mm), and all aneurysms were wide-neck. WEB deployment failed in 1 case due to WEB protrusion in a small PICA aneurysm. Additional stent implantation was required for 2 aneurysms to improve intra-aneurysmal WEB positioning. One patient developed a partial posterior cerebral artery territory infarction with transient hemianopsia. Intraoperative rerupture of a ruptured aneurysm could be immediately stopped by WEB deployment due to intrasaccular stasis; however, it might have contributed to a slight disability of the patient. At last angiographic follow-up, 12/15 aneurysms (80%) were completely occluded and 3/15 (20%) had a neck remnant.

CONCLUSIONS

The preliminary results indicate that WEB treatment of proximal PICA aneurysms is feasible with a reasonable safety and efficacy profile. The advantages of intrasaccular flow disruption include preservation of the PICA, durable aneurysm occlusion, and omission of antiplatelet therapy. The low-profile WEB 17 delivery system might enable navigation to distal PICA aneurysms, which needs to be addressed further.

Flow Diversion for ICA Aneurysms with Compressive Neuro-Ophthalmologic Symptoms: Predictors of Morbidity, Mortality, and Incomplete Aneurysm Occlusion

BACKGROUND AND PURPOSE

Flow diversion is an effective treatment for aneurysms of the ICA with compression-related neuro-ophthalmologic symptoms, especially when treatment is initiated early after symptom onset and aneurysm occlusion is complete. However, non-negligible complication rates have been reported. Our aim was to identify risk factors for morbidity/mortality and incomplete aneurysm occlusion.

MATERIALS AND METHODS

We performed a secondary analysis of a previous publication, which included all patients treated with flow diversion for an unruptured aneurysm of the ICA with compression-related symptoms.

RESULTS

Fifty-four patients with 54 aneurysms (48 women, 88.9%; mean age, 59.2 [SD, 15.9] years; range, 21-86 years) treated with flow diversion were included. We observed morbidity and mortality rates of 7.4% and 3.7%. Increasing age (OR per decade, 3.2; 95% CI, 1.23-8.49; P = .02) and dual-antiplatelet therapy with ticagrelor (OR, 13.9; 95% CI, 1.16-165.97; P = .04) were significantly associated with morbidity/mortality. After a median follow-up of 13.3 [SD, 10.5] months, the rates of complete aneurysm occlusion, neck remnant, and aneurysm remnant were 74%, 14%, and 12%. Incomplete occlusion at follow-up was less frequently observed in aneurysms treated with additional coil embolization (OR, 0.1; 95% CI, 0.01-0.86; P = .04).

CONCLUSIONS

Although a promising treatment for compressive ICA aneurysms, flow diversion carries a relevant risk for complications and incomplete aneurysm occlusion. Our results may help identify patients in which flow diversion may not be the ideal treatment method. Additional coil embolization increased the likelihood of complete aneurysm occlusion at follow-up.

Automated Color-Coding of Lesion Changes in Contrast-Enhanced 3D T1-Weighted Sequences for MRI Follow-up of Brain Metastases

BACKGROUND AND PURPOSE

MR imaging is the technique of choice for follow-up of patients with brain metastases, yet the radiologic assessment is often tedious and error-prone, especially in examinations with multiple metastases or subtle changes. This study aimed to determine whether using automated color-coding improves the radiologic assessment of brain metastases compared with conventional reading.

MATERIALS AND METHODS

One hundred twenty-one pairs of follow-up examinations of patients with brain metastases were assessed. Two radiologists determined the presence of progression, regression, mixed changes, or stable disease between the follow-up examinations and indicated subjective diagnostic certainty regarding their decisions in a conventional reading and a second reading using automated color-coding after an interval of 8 weeks.

RESULTS

The rate of correctly classified diagnoses was higher (91.3%, 221/242, versus 74.0%, 179/242, P < .01) when using automated color-coding, and the median Likert score for diagnostic certainty improved from 2 (interquartile range, 2-3) to 4 (interquartile range, 3-5) (P < .05) compared with the conventional reading. Interrater agreement was excellent (κ = 0.80; 95% CI, 0.71-0.89) with automated color-coding compared with a moderate agreement (κ = 0.46; 95% CI, 0.34-0.58) with the conventional reading approach. When considering the time required for image preprocessing, the overall average time for reading an examination was longer in the automated color-coding approach (91.5 [SD, 23.1] seconds versus 79.4 [SD, 34.7 ] seconds, P < .001).

CONCLUSIONS

Compared with the conventional reading, automated color-coding of lesion changes in follow-up examinations of patients with brain metastases significantly increased the rate of correct diagnoses and resulted in higher diagnostic certainty.

P14.41 Cost-effectiveness of FET PET for early treatment response assessment in glioma patients following adjuvant temozolomide chemotherapy

BACKGROUND

In light of increasing healthcare costs, higher medical expenses should be justified socio-economically. Therefore, we calculated the effectiveness and cost-effectiveness of PET using the radiolabeled amino acid O-(2-[18F]-fluoroethyl)-L-tyrosine (FET) compared to conventional MRI for early identification of responders to adjuvant temozolomide chemotherapy. A recent study in IDH-wildtype glioma patients suggested that after two cycles, FET-PET parameter changes predicted a significantly longer survival while MRI changes were not significant.

MATERIALS AND METHODS

To determine the effectiveness and cost-effectiveness of serial FET-PET imaging, we analyzed published clinical data and calculated the associated costs in the context of the German healthcare system.Based on a decision-tree model, FET-PET and MRI’s effectiveness was calculated, i.e., the probability to correctly identify a responder as defined by an overall survival ≥15 months. To determine the cost-effectiveness, the incremental cost-effectiveness ratio (ICER) was calculated, i.e., the cost for each additionally identified responder by FET-PET who would have remained undetected by MRI. The robustness of the results was tested by deterministic and probabilistic (Monte Carlo simulation) sensitivity analyses.

RESULTS

Compared to MRI, FET-PET increases the rate of correctly identified responders to chemotherapy by 26%; thus, four patients need to be examined by FET-PET to identify one additional responder. Considering the respective cost for serial FET-PET and MRI, the ICER resulted in €4,396.83 for each additional correctly identified responder by FET-PET. The sensitivity analyses confirmed the robustness of the results.

CONCLUSION

In contrast to conventional MRI, the model suggests that FET PET is cost-effective in terms of ICER values. Concerning the high cost of temozolomide, the integration of FET-PET has the potential to avoid premature chemotherapy discontinuation at a reasonable cost.

True first-pass effect in basilar artery occlusions: First-pass complete reperfusion improves clinical outcome in stroke thrombectomy patients

BACKGROUND

Complete reperfusion (mTICI 3) in anterior circulation ischemic stroke patients after a single mechanical thrombectomy (MT) pass has been identified as a predictor of favorable outcome (modified Rankin Score 0-2) and defined as true first-pass effect recently. This effect has not yet been demonstrated in posterior circulation ischemic stroke. We hypothesized a true first-pass effect for the subgroup of acute basilar artery occlusions (BAO).

METHODS

Consecutive patients with acute thromboembolic occlusions in the posterior circulation, treated between 2010 and 2017, were screened and all BAO patients with complete angiographic reperfusion and known symptom onset included for unmatched and matched analysis after adjustment for multiple confounding factors (demographics, time intervals, stroke severity, posterior circulation Alberta Stroke Program early computed tomography Score and comorbidity. The primary objective was outcome at 90 days between matched cohorts of single pass vs. multi pass complete reperfusion patients.

RESULTS

90 MTs in BAO were analyzed, yielding 56 patients with known symptom onset, in whom we achieved complete reperfusion (mTICI 3), depending on whether complete reperfusion was achieved after a single pass (n = 28) or multiple passes (n = 28). Multivariable analysis of 56 non-matched patients revealed a significant association between first-pass complete reperfusion and favorable outcome (p < 0.01). In matched cohorts (n = 7 vs. n = 7), favorable outcome was only seen if complete reperfusion was achieved after a single pass (86% vs. 0%).

CONCLUSION

Single pass complete reperfusion in acute basilar artery occlusion is an independent predictor of favorable outcome. Achieving complete reperfusion after multiple passes might impair favorable patient recovery.

Automated Detection and Segmentation of Brain Metastases in Malignant Melanoma: Evaluation of a Dedicated Deep Learning Model

BACKGROUND AND PURPOSE

Malignant melanoma is an aggressive skin cancer in which brain metastases are common. Our aim was to establish and evaluate a deep learning model for fully automated detection and segmentation of brain metastases in patients with malignant melanoma using clinical routine MR imaging.

MATERIALS AND METHODS

Sixty-nine patients with melanoma with a total of 135 brain metastases at initial diagnosis and available multiparametric MR imaging datasets (T1-/T2-weighted, T1-weighted gadolinium contrast-enhanced, FLAIR) were included. A previously established deep learning model architecture (3D convolutional neural network; DeepMedic) simultaneously operating on the aforementioned MR images was trained on a cohort of 55 patients with 103 metastases using 5-fold cross-validation. The efficacy of the deep learning model was evaluated using an independent test set consisting of 14 patients with 32 metastases. Manual segmentations of metastases in a voxelwise manner (T1-weighted gadolinium contrast-enhanced imaging) performed by 2 radiologists in consensus served as the ground truth.

RESULTS

After training, the deep learning model detected 28 of 32 brain metastases (mean volume, 1.0 [SD, 2.4] cm³) in the test cohort correctly (sensitivity of 88%), while false-positive findings of 0.71 per scan were observed. Compared with the ground truth, automated segmentations achieved a median Dice similarity coefficient of 0.75.

CONCLUSIONS

Deep learning-based automated detection and segmentation of brain metastases in malignant melanoma yields high detection and segmentation accuracy with false-positive findings of <1 per scan.

Postinterventional Assessment after Stent and Flow-Diverter Implantation Using CT: Influence of Spectral Image Reconstructions and Different Device Types

BACKGROUND AND PURPOSE

CTA provides a noninvasive alternative technique to DSA in the follow-up after endovascular aneurysm treatment to evaluate aneurysm occlusion and exclude intraluminal narrowing after stent or flow-diverter implantation; however, assessability may be impeded by stent material artifacts. The objective of this in vitro study was to compare the visual assessability of different conventional stents and flow diverters as well as different reconstructions of dual-layer CT images.

MATERIALS AND METHODS

Four conventional intracranial stents and 4 flow diverters were implanted in identical aneurysm phantoms. Conventional and monoenergetic images (40, 50, 60, 90, 120, 180 keV) were acquired to evaluate attenuation alteration, visible lumen diameter, and SNR. Image quality was rated subjectively by 2 independent radiologists using a 4-point Likert scale.

RESULTS

Low kiloelectron volt (40-60 keV) monoenergetic reconstructions showed an improved SNR and an improved lumen density ratio compared with high kiloelectron volt reconstructions (90-180 keV) and conventional reconstructions, however without reaching significance compared with the latter. Assessment of the adjacent aneurysm and subjective evaluation was not affected by the imaging technique and stent type. Artifact susceptibility varied with the device used and increased among flow diverters.

CONCLUSIONS

Low kiloelectron volt reconstructions improved the assessment of the stent lumen in comparison with high kiloelectron volt reconstructions. No significant improvement in image quality could be shown compared with conventional images. For some devices, iodine-specific reconstructions led to severe artifacts and are therefore not recommended. There was no relevant improvement in the assessability of the adjacent aneurysm.

Periprocedural Safety and Feasibility of the New LVIS EVO Device for Stent-Assisted Coiling of Intracranial Aneurysms: An Observational Multicenter Study

BACKGROUND AND PURPOSE

Stent-assisted treatment techniques can be an effective treatment option for intracranial aneurysms. The aim of this study was to evaluate the periprocedural feasibility and safety of the new LVIS EVO stent for the treatment of intracranial aneurysms.

MATERIALS AND METHODS

Patients with intracranial aneurysms treated with the LVIS EVO in 11 European neurovascular centers were retrospectively reviewed. Patient and aneurysm characteristics, procedural parameters, immediate grade of occlusion, and technical and clinical complications were assessed.

RESULTS

Fifty-seven patients with 59 aneurysms were treated with the LVIS EVO device; 57.6% of the aneurysms were incidental; 15.3% were acutely ruptured; 15.3% were recanalized or residual aneurysms; and 11.9% were treated for symptoms other than acute hemorrhage. The most frequent aneurysm locations were the middle cerebral artery (25.4%) and the anterior communicating artery (22.0%). The rate of immediate successful deployment was 93.2%. In 6.8% (n = 4) of cases, additional in-stent angioplasty was needed. The immediate complete occlusion rate was 54.2%, while there was a residual aneurysm in 35.6% and a residual neck in 10.2%. Periprocedural technical complications occurred in 7/59 treatments (11.9%; the most frequent technical complication [n = 3] was thrombus formation), which all resolved completely without clinical sequelae. Postprocedural neurologic complications occurred after 4/59 treatments (6.8%; 2 transient ischemic attacks, 1 minor stroke, 1 major stroke), of which only 1 persistent complication was directly related to the procedure (minor stroke in the vascular territory distal to the stent).

CONCLUSIONS

The LVIS EVO stent is a safe, feasible device for the treatment of intracranial aneurysms.

Comparative analysis of CGUARD embolic prevention stent with Casper-RX and Wallstent for the treatment of carotid artery stenosis

Stent protected Angioplasty of extracranial carotid artery stenosis using the dual-layered CGUARD stent is a novel treatment option. In this study we evaluate the feasibility and the safety of the CGUARD in symptomatic and asymptomatic patients in comparison to Casper-RX and Wallstent. This is a multi-center study of consecutive patients treated with the CGUARD, Casper-RX and Wallstent at two German high volume neurovascular centers between April 2017 and May 2018. Patient characteristics, neuroimaging data and angiographic outcome were retrospectively analyzed. The primary end points of the study were acute occlusion of the carotid stent and symptomatic intracerebral hemorrhage (sICH). Carotid artery stenting was performed in 76 patients; of those 26 (34%) were treated with the CGUARD, 25 (33%) with Casper-RX, and 25 (33%) with Wallstent. In 58/76 (76%) cases carotid artery stenosis was symptomatic with a median baseline National Institutes of Health Stroke Scale of 4. Angioplasty and stenting as part of a mechanical thrombectomy for acute ischemic stroke was performed in 25/76 (33%) patients. Baseline patient characteristics were similar between the treatment groups, except for a higher portion of scheduled cases in the Casper-RX group. There were no significant differences in the rate of acute in stent occlusions (CGUARD, 2/26 (8%); Casper-RX, 1/25(4%); Wallstent, 1/25 (4%)) and postinterventional sICH (1/26 (4%), 0/25(0%), 0/25 (0%)). Clinical outcome at discharge did not differ between groups. Treatment of carotid artery stenosis using CGUARD is feasible with a good safety profile comparable to that of Casper-RX and Wallstent.

Virtual Monoenergetic Images from Spectral Detector CT Enable Radiation Dose Reduction in Unenhanced Cranial CT

BACKGROUND AND PURPOSE

Our aim was to evaluate whether improved gray-white matter differentiation in cranial CT by means of 65- keV virtual monoenergetic images enables a radiation dose reduction compared to conventional images.

MATERIALS AND METHODS

One hundred forty consecutive patients undergoing 171 spectral detector CTs of the head between February and November 2017 (56 ± 19 years of age; male/female ratio, 56%/44%) were retrospectively included. The tube current-time product was reduced during the study period, resulting in 61, 55, and 55 patients being examined with 320, 290, and 260 mAs, respectively. All other scanning parameters were kept identical. The volume CT dose index was recorded. ROIs were placed in gray and white matter on conventional images and copied to identical positions in 65- keV virtual monoenergetic images. The contrast-to-noise ratio was calculated. Two radiologists blinded to the reconstruction technique evaluated image quality on a 5-point Likert-scale. Statistical assessment was performed using ANOVA and Wilcoxon test adjusted for multiple comparisons.

RESULTS

The mean volume CT dose index was 55, 49.8, and 44.7 mGy using 320, 290, and 260 mAs, respectively. Irrespective of the volume CT dose index, noise was significantly lower in 65- keV virtual monoenergetic images compared with conventional images (65- keV virtual monoenergetic images/conventional images: extraocular muscle with 49.8 mGy, 3.7 ± 1.3/5.6 ± 1.6 HU, P < .001). Noise slightly increased with a reduced radiation dose (eg, extraocular muscle in conventional images: 5.3 ± 1.4/5.6 ± 1.6/6.1 ± 2.1 HU). Overall, the contrast-to-noise ratio in 65- keV virtual monoenergetic images was superior to that in conventional images irrespective of the volume CT dose index (P < .001). Particularly, 65-keV virtual monoenergetic images with 44.7 mGy showed significantly lower noise and a higher contrast-to-noise ratio than conventional images with 55 mGy (P < .001). Subjective analysis confirmed better image quality in 65- keV virtual monoenergetic images, even using 44.7 mGy.

CONCLUSIONS

The 65-keV virtual monoenergetic images from spectral detector CT allow radiation dose reduction in cranial CT. While this proof of concept included a radiation dose reduction of 19%, our data suggest that even greater reduction appears achievable.

P14.17 Differentiation of treatment-related changes from tumor progression: A direct comparison between dynamic FET PET and ADC values obtained from DWI MRI

BACKGROUND

Following brain cancer treatment, the capacity of anatomical MRI to differentiate neoplastic tissue from treatment-related changes (e.g., pseudoprogression) is limited. This study compared apparent diffusion coefficients (ADC) obtained by diffusion-weighted MRI (DWI) with static and dynamic parameters of O-(2-[18F]fluoroethyl)-L-tyrosine (FET) PET for the differentiation of treatment-related changes from tumor progression.

MATERIAL AND METHODS

Forty-eight pretreated high-grade glioma patients with anatomical MRI findings suspicious for progression (median time elapsed since last treatment, 16 weeks) were investigated using DWI and dynamic FET PET. Maximum and mean tumor-to-brain ratios (TBRmax, TBRmean) as well as dynamic parameters (time-to-peak and slope values) of FET uptake were calculated. For mean ADC calculation, regions-of-interest analyses were performed on ADC maps calculated from DWI co-registered with the contrast-enhanced MR image. Diagnoses were confirmed neuropathologically (21%) or clinicoradiologically. Diagnostic performance was evaluated using receiver-operating-characteristic analyses or Fisher’s exact test for a combinational approach.

RESULTS

Ten of 48 patients had treatment-related changes (21%). The diagnostic performance of FET PET was significantly higher (threshold for both TBRmax and TBRmean, 1.95; accuracy, 83%; AUC, 0.89±0.05; P<0.001) than that of ADC values (threshold ADC, 1.09x10-3 mm2/s; accuracy, 69%; AUC, 0.73±0.09; P=0.13). The addition of static FET PET parameters to ADC values increased the latter’s accuracy to 89%. The highest accuracy was achieved by combining static and dynamic FET PET parameters (93%).

CONCLUSION

Data suggest that static and dynamic FET PET provide valuable information concerning the differentiation of early treatment-related changes from tumor progression and outperform ADC measurement for this highly relevant clinical question.

Low-Profile Intra-Aneurysmal Flow Disruptor WEB 17 versus WEB Predecessor Systems for Treatment of Small Intracranial Aneurysms: Comparative Analysis of Procedural Safety and Feasibility

BACKGROUND AND PURPOSE

The Woven EndoBridge 17 has recently been introduced to the market for facilitated endovascular treatment of small bifurcation aneurysms (≤7 mm) with low-profile microcatheters. We compared the Woven EndoBridge 17 with its predecessor versions in terms of procedural safety and feasibility.

MATERIALS AND METHODS

This was a multicenter review of aneurysms ranging from 3 to 7 mm treated with the Woven EndoBridge between 2011 and 2019. Aneurysm characteristics, procedural parameters, and complications were retrospectively compared between treatment with the Woven EndoBridge 17 and a control group that was treated with its predecessor versions, using inverse probability of treatment weighting.

RESULTS

Thirty-eight aneurysms treated with a Woven EndoBridge 17 (mean size, 4.9 ± 1.5 mm) and 70 treated with a predecessor version of the Woven EndoBridge 17 (mean size, 5.6 ± 1.4 mm) were included. The predecessor version of the Woven EndoBridge 17 had a higher failure rate (10.3%) than the Woven EndoBridge 17 (0%, P = .05). Additional stent placement was performed more often with the predecessor version of the Woven EndoBridge 17 (10.0%) than with the Woven EndoBridge 17 (2.6%, adjusted P = .005). The predecessor version of the Woven EndoBridge 17 was associated with a higher thromboembolic event rate (14.3%) than the Woven EndoBridge 17 (5.3%, adjusted P = .002). Neurologic complications (Woven EndoBridge 17: 2.6%; predecessor version of the Woven EndoBridge 17: 2.9%, adjusted P = 1.0) and immediate complete aneurysm occlusion rates (Woven EndoBridge 17: 57.9%; predecessor version of the Woven EndoBridge 17: 54.3%, adjusted P = .21) did not differ significantly between groups.

CONCLUSIONS

In the current study, the Woven EndoBridge 17 was associated with a potentially lower thromboembolic event rate than the predecessor version of the Woven EndoBridge 17, without compromising the immediate aneurysm occlusion rate. Long-term clinical and angiographic outcome analysis will be necessary to draw a definite conclusion.

[Importance of interdisciplinary collaboration for optimal treatment of orbital tumors]

Optimal treatment of tumors with orbital invasion may exceed the competences of an individual medical specialty and require interdisciplinary cooperation. The aim of this article is to present an interdisciplinary treatment concept based on the examples of intraorbital hemangioma and squamous cell carcinoma of the paranasal sinuses infiltrating the orbit. In addition to a detailed medical history and a complete ophthalmological examination, a detailed imaging technique with standardized echography and tomography methods such as orbital thin-slice CT and/or in many cases MRI is essential for the primary classification of an intraorbital pathology. Depending on the type of pathology, a purely surgical procedure involving various disciplines such as ophthalmology, otorhinolaryngology, maxillofacial surgery, neurosurgery, and pathology, or an interdisciplinary treatment regimen including (neo)adjuvant radiotherapy or chemotherapy is necessary. Orbital tumors have a wide range of potential pathologies, requiring complex surgical procedures and multimodal therapies. In case of infiltration of the paranasal sinuses or intracranial structures, an interdisciplinary team including neuroradiologists, oral-maxillofacial surgeons, otorhinolaryngologists, neurosurgeons, radiation therapists, ophthalmologists, pathologists, oncologists, and psycho-oncologists is essential for successful treatment.

[The Therapeutic Dilemma in Treatment of Intracranial Infectious Aneurysm in Patients with Infective Endocarditis: Proposal for a Patient-Centered, Interdisciplinary Treatment Concept]

Intracranial infectious aneurysms are rare but hazardous complications of an infective endocarditis. To date, there are no evidence-based recommendations for the treatment of patients with this condition. Therefore, it remains an interdisciplinary challenge to decide which treatment steps are required and in which order they should be carried out. To illustrate the interdisciplinary dilemma in the treatment of these patients, we here present a case of a 23-year-old, drug-addicted woman with infectious endocarditis. While antibiotic treatment of the streptococcus-mitis-induced endocarditis stabilized the overall status of the patient, rupture of a basilar artery aneurysm caused her sudden death. We discuss the decision-making processes of the treatment, potential difficulties and dilemmas when dealing with patients suffering from infectious endocarditis and infectious intracranial aneurysm. Based upon case reports, studies and reviews, we present the options and risks of conservative, neurosurgical, endovascular, and cardiosurgical treatment of intracranial infectious aneurysms, and propose a patient-centered, interdisciplinary treatment concept.

First-line lesional aspiration in acute stroke thrombectomy using a novel intermediate catheter: Initial experiences with the SOFIA

INTRODUCTION

Five randomized controlled trials (RCTs) on endovascular therapy (EVT) of stroke have proven a clinical benefit over conservative treatment or IV-thrombolysis alone. Lesional clot aspiration with a dedicated system can achieve revascularization without an additional retriever (a direct-aspiration first-pass technique, ADAPT), and the SOFIA has been shown to be both safe and efficacious in a multicentric retrospective study. We have evaluated a subset of these data acquired in two major stroke centers with regard to using the SOFIA for first-line lesional aspiration.

METHODS

Thirty patients with large-vessel occlusions treated with first-line lesional aspiration were identified. Procedural data, clot length, reperfusion success (mTICI), procedural timings, complications, and clinical status at admission, discharge and at 90 days were analyzed.

RESULTS

The median baseline NIHSS was 16. IV thrombolysis was administered in 15/30 patients. Ninety-three percent of occlusions were in the anterior circulation. TICI ≥ 2b was achieved in 90% of multimodality treatments; lesional aspiration was successful in 67% within a median time of 20 minutes. The highest first-attempt success rate was in MCA occlusions (median time to recanalization 10 minutes). There were no device-related events. Symptomatic intracerebral hemorrhage (sICH) occurred in 10%, but never with sole lesional aspiration. Embolization to new territories was recorded in 1/30 (3%). Median discharge NIHSS was 7; 30% were mRS ≤ 2 at discharge and 43% at 90-day follow-up.

CONCLUSIONS

Lesional aspiration with SOFIA is in line with published data. The SOFIA may be used as a first-line device, aiming at fast recanalization by sole aspiration with good safety and efficacy. If unsuccessful, it converts into part of a stent retriever-based multimodality treatment.

WEB as part of a multimodality treatment in complex, large, and partially thrombosed intracranial aneurysms: a single-center observational study of technical success, safety, and recurrence

Introduction

Complex, large, wide-neck aneurysms, but particularly partially thrombosed intracranial aneurysms (PTIAs), have a greater tendency to recanalize after coil occlusion. The Woven Endovascular Bridge (WEB) combines shape memory wires braided to a relatively uniform, dense surface, which may limit its compaction and its incorporation into an existing aneurysm clot and may thus reduce PTIA recurrence.

Objective

To carry out a retrospective analysis of our experience with the WEB as part of a complex treatment in conjunction with other implants to assess the efficacy and safety of this technique.

Methods

Among 43 aneurysms treated with the WEB in our center, eight complex, large, wide-neck aneurysms were treated in conjunction with other implants (additional WEBs, coils, stents, flow diverters). Six of these eight aneurysms were PTIAs. All patients were followed up by DSA between 3½ and 38 months.

Results

All eight (100%) of the complex, large, wide-neck aneurysms were treated successfully and without periprocedural adverse events (0%). At follow-up, the two non-thrombosed aneurysms were completely occluded, but all six PTIAs recurred (75%) and were re-treated. There was no morbidity or mortality in these eight patients.

Conclusions

Treatment of large, complex aneurysms with the WEB in conjunction with other implants was technically successful and safe but did not prevent recurrence of partially thrombosed aneurysms in our center. PTIA re-treatment was possible and not limited by the previously placed WEB.

Stent Retriever Thrombectomy in Patients Who Are Ineligible for Intravenous Thrombolysis: A Multicenter Retrospective Observational Study

BACKGROUND AND PURPOSE

Intravenous thrombolysis with rtPA is the standard of care for patients with acute ischemic stroke within 4.5 hours after symptom onset. However, a considerable number of patients are ineligible for IV thrombolysis due to various contraindications. Recent studies have proved the superiority of mechanical thrombectomy for patients with large-vessel occlusions in combination with IV rtPA compared with IV rtPA alone. We aimed to demonstrate the efficacy of mechanical thrombectomy for patients who are ineligible for IV rtPA.

MATERIALS AND METHODS

Patients from the stroke registries of 4 dedicated centers who were treated with mechanical thrombectomy from January 2010 to October 2014 were retrospectively evaluated. Inclusion criteria were the following: acute stroke due to proved large-artery occlusion, ineligibility for IV thrombolysis, and a timeframe of ≤4.5 hours between stroke and the start of mechanical thrombectomy. Recanalization success, periprocedural complications, clinical outcome, and hemorrhages were evaluated.

RESULTS

One hundred thirty endovascular recanalization procedures were identified. The locations were the following: proximal ICA in 17 (13.1%), terminus ICA in 25 (19.2%), M1 segment in 77 (59.2%), and M2 segment in 11 (8.5%). TICI 2b/3 results were achieved in 101 (77.7%), and an mRS score of 0-2 in 47 patients (37.9%). There was a significant correlation between TICI 2b/3 results and good clinical outcomes (87.2% versus 6.8%; P = .048). A good clinical result was most frequent when recanalization was achieved within 4.5 hours (37/74 = 50% versus 10/50 = 20.0%; P = .001). Symptomatic hemorrhage occurred in 13.1% of patients; mortality was 24.2%. Periprocedural complications were recorded in 10 patients (7.7%).

CONCLUSIONS

Mechanical thrombectomy can achieve good clinical outcomes in patients with acute large-artery occlusion ineligible for IV thrombolysis, in particular when recanalization is reached early.

Emergency Stenting of the Extracranial Internal Carotid Artery in Combination with Anterior Circulation Thrombectomy in Acute Ischemic Stroke: A Retrospective Multicenter Study

BACKGROUND AND PURPOSE

Several small case series reported a favorable clinical outcome for emergency stent placement in the extracranial internal carotid artery combined with mechanical thrombectomy in acute stroke. The rate of postinterventional symptomatic intracranial hemorrhages was reported to be as high as 20%. Therefore, we investigated the safety and efficacy of this technique in a large multicentric cohort.

MATERIALS AND METHODS

The data bases of 4 German stroke centers were screened for all patients who received emergency stent placement of the extracranial internal carotid artery in combination with mechanical thrombectomy of the anterior circulation between 2007 and 2014. The primary outcome measure was the rate of symptomatic intracranial hemorrhage according to the European Cooperative Acute Stroke Study III criteria; secondary outcome measures included the angiographic revascularization results and clinical outcome.

RESULTS

One hundred seventy patients with a median age of 64 years (range, 25-88 years) were treated. They presented after a median of 98 minutes (range, 52-160 minutes) with a median NIHSS score of 15 (range, 12-19). Symptomatic intracranial hemorrhages occurred in 15/170 (9%) patients; there was no statistically significant difference among groups pertaining to age, sex, intravenous rtPA, procedural timings, and the rate of successful recanalization. In 130/170 (77%) patients, a TICI score of ≥ 2b could be achieved. The in-hospital mortality rate was 19%, and 36% of patients had a favorable outcome at follow-up.

CONCLUSIONS

Emergency stent placement in the extracranial internal carotid artery in combination with anterior circulation thrombectomy is effective and safe. It is not associated with a significantly higher risk of symptomatic intracranial hemorrhage compared with published series for mechanical thrombectomy alone.

Intrasaccular Flow Disruption in Acutely Ruptured Aneurysms: A Multicenter Retrospective Review of the Use of the WEB

BACKGROUND AND PURPOSE

Use of the WEB intra-aneurysmal flow-disruption device in unruptured wide-neck bifurcation aneurysms has proven safety and efficacy. However, ruptured aneurysms are underrepresented in existing studies. This retrospective multicenter study describes the use of the WEB in patients with a ruptured intracranial aneurysm.

MATERIALS AND METHODS

Ten centers contributed to this study. Clinical and procedural data of 47 patients with 52 aneurysms were analyzed retrospectively together with follow-up angiographies.

RESULTS

There were 37 anterior and 15 posterior circulation aneurysms with a neck size of ≥4 mm in 49 of 52 (94%) aneurysms; 45 (87%) aneurysms were <10 mm, and 2 were partially thrombosed. Successful placement of the WEB was possible in every case. Adjunctive devices were used in 8 of 52 (15%) aneurysms. Thromboembolic events were observed in 4 of 52 (8%) patients. Adverse events occurred in 15 patients with 16 aneurysms, 9 of which were potentially related to the WEB procedure (3 thromboembolic events, 5 protrusions, and 1 perforations; 2 perforations were caused by the wire or catheter), but none had a clinical impact. Four patients were retreated. Short-term follow-up in 25 of 39 patients revealed complete occlusion in 15 of 25 (60%), 5 of 25 (20%) with residual neck, and 5 of 25 (20%) with residual aneurysm filling. Short- to midterm imaging in 9 of 25 patients revealed complete occlusion in 5 (55.6%), residual neck in 2 (22%), and residual aneurysm filling in 2 (22%). Of 47 patients, 23 (49%) had an mRS score of 0, 1, or 2; 13 (28%) had an mRS score of 3 or 4; and none had an mRS score of 5 at discharge.

CONCLUSIONS

This retrospective series showed good procedural safety, feasibility, and stability of midterm occlusion in ruptured wide-neck bifurcation aneurysms.

Initial Clinical Experience with a New Self-Expanding Nitinol Microstent for the Treatment of Wide-Neck Intracranial Cerebral Aneurysms: The Acandis Acclino Stent

BACKGROUND AND PURPOSE

The Acclino is a laser-cut closed-cell microstent composed of nitinol. It was developed for stent-assisted coiling of wide-neck intracranial aneurysms. The key feature of the stent is its deployability via low-profile microcatheters with an inner diameter of 0.0165 inch, which are also suited for coil deployment. The objective of this study was to evaluate the safety and feasibility as well as the immediate and mid-term results of this new device.

MATERIALS AND METHODS

Our database was screened for all Acclino-based stent-assisted intracranial coil embolizations since its introduction to the European market in June 2012. Case files and imaging data were retrospectively analyzed for angiographical and clinical outcome parameters, including immediate and mid-term modified Raymond-Roy aneurysm occlusion classification (RROC) rates and procedural complications.

RESULTS

Fourteen patients comprising 14 aneurysms (9 unruptured and 5 ruptured) were treated with the Acclino. All except for a dissecting one were wide-neck saccular aneurysms. Immediate complete occlusion (RROC1) was observed in 8/14 cases (57%), a residual neck (RROC2) in 4/14 (29%), and a persistent filling of the dome (RROC 3) in 1/14 cases (7%). An in-stent thrombus formation in one case (7%) was medically resolved without neurological deficit. Follow-up was available in 9/14 cases (64%) after a mean of 137 days (SD ± 50). All followed cases depicted a complete occlusion (RROC1).

CONCLUSIONS

The Acclino microstent showed a satisfactory safety profile and a promising rate of immediate and mid-term complete aneurysm occlusion for stent-assisted coil embolization in wide-neck intracranial aneurysms, warranting further investigation of the device.

Mechanical thrombectomy in tandem occlusion: procedural considerations and clinical results

INTRODUCTION

Acute tandem occlusions of the cervical and distal internal carotid artery (ICA) or middle cerebral artery (MCA) are associated with major stroke with intravenous (i.v.) thrombolysis alone in approximately 90 % of patients. The data on endovascular management of tandem occlusions is still limited. The purpose of this study was to review technical aspects and the current state of the literature on acute ICA stenting in combination with stent retriever-based intracranial thrombectomy.

METHODS

We retrospectively reviewed the data of 37 consecutive patients with tandem occlusions including clinical parameters, angiographic results, procedural aspects, complications, and hemorrhages.

RESULTS

Median National Institutes of Health Stroke Scale (NIHSS) on admission was 17 (3-30). Intracranial thrombectomy was performed prior to ICA stenting in 25/37 (67.6 %) and after stenting in 12/37 (32.4 %) patients. ICA stenting was successful in all cases, and a thrombolysis in cerebral infarction (TICI) scale 2b/3 result was achieved in 27/37 (73 %) cases. The mean angiography time was significantly shorter in the "thrombectomy first" group (43.1 ± 30.8 vs. 110.8 ± 43.0 min, p < 0.001), and more patients had favorable outcomes after 3 months (13/25 = 52.0 vs. 4/12 = 33.3 %, p = 0.319). In this group, intermediate catheters were used and successfully prevented embolism to unaffected territories in all cases.

CONCLUSION

Acute stenting of the cervical ICA in combination with intracranial thrombectomy was technically feasible and safe in our series. Thrombectomy prior to proximal stenting was associated with shorter reperfusion times and a tendency towards better clinical outcome leading to a good outcome in about 50 % of the patients. Therefore, we recommend this approach in tandem occlusion requiring stent angioplasty.

[Experiences with power-injectable port systems: complications, patient satisfaction and clinical benefit]

PURPOSE

Evaluation of complications, patient satisfaction and clinical benefit of port systems with authorization for high pressure injection of contrast agent during CT/MR examinations.

MATERIALS AND METHODS

Ultrasound-guided insertions of central venous port catheters were performed through the lateral subclavian vein at a university teaching hospital. The radiological information system (HIS/RIS) was used to evaluate technical success and complication rates. Assessment of patient satisfaction and clinical benefit was carried out by a questionnaire during a telephone call 6 months after implantation of the port system.

RESULTS

A total of 195 port systems in 193 patients were implanted. The catheter remained in place for a mean duration of 169 days (overall 29,210 catheter days). The technical success rate was 99.5 % and the overall complication rate was 17.4 % (24/138; 0.82 per 1000 catheter days). Follow-up revealed 13 early port explantations (9 %). Most of the patients reported high satisfaction in general (satisfied/very satisfied: 94 %). 34/209 contrast-enhanced CT/MRT scans (16 %) were performed using the port for contrast media injection. There were no complications during or after administration of contrast agent via the port system.

CONCLUSION

The Powerport system is a safe alternative for peripheral i. v. contrast media injection during CT/MR scans, but has been infrequently used. Most patients reported high overall satisfaction with the port system.

Intrasaccular flow-disruption treatment of intracranial aneurysms: preliminary results of a multicenter clinical study

BACKGROUND AND PURPOSE

The endovascular treatment of intracranial aneurysms with unfavorable anatomy (large aneurysms, wide-neck) is frequently challenging and is also associated with a high incidence of significant recurrences. The WEB, an intrasaccular flow disrupter, was designed for use in this type of aneurysm. We report our early experience with this device in this multicenter study.

MATERIALS AND METHODS

Twenty patients with 21 aneurysms were treated by using the WEB in 3 European centers. The ability to successfully deploy the WEB, immediate posttreatment angiographic results, adverse events, clinical outcome, and angiographic follow-up results were recorded.

RESULTS

Aneurysm location was the ICA (4/21, 19.1%), MCA (8/21, 38.1%), AcomA (5/21, 23.8%), and BA (4/21, 19.1%). No treatment failures were reported. Treatment was performed exclusively with the WEB in 16/21 (76.2%) patients. Additional treatment (coiling and/or stent placement) was used in 5/21 (23.8%) patients. One patient (4.8%) experienced transient clinical worsening (mRS 1 at 1 month, mRS 0 at 3 months) related to a thromboembolic event. Inadvertent detachment of the WEB was observed, and the WEB was retrieved in 1 patient, without adverse effects. In the short-term follow-up (2-8 months), adequate occlusion (total occlusion or neck remnant) was observed in 80.0% of aneurysms.

CONCLUSIONS

Intrasaccular flow disruption is a new endovascular approach for aneurysm treatment. In our preliminary experience, this treatment was feasible and mostly used in bifurcation aneurysms (MCA, BA, ICA) with unfavorable anatomy. Further studies are needed to precisely evaluate the indications, safety, and efficacy of this new technique.

[Occlusion of the left portal vein in newborns]

PURPOSE

The occlusion of the left portal vein in newborn infants is shown and discussed in 14 cases.

MATERIALS AND METHODS

The occlusion of the left portal vein in ten male and in four female newborn infants was diagnosed using ultrasound. Only one of the newborn infants was treated with an umbilical vessel catheter. In one case the occlusion of the left portal vein was suspected in an MRI. In the remaining 12 patients, the diagnosis was an incidental finding.

RESULTS

Real-time ultrasound showed a hyperechogenic left portal vein without receiving a signal in duplex sonography in thirteen patients. A partly obstructive thrombus was only seen in one patient. Seven patients had enlarged and increased liver arteries already during the primary examination. Recanalization was achieved in two patients who received anticoagulative treatment and in one patient spontaneously. In the other eleven patients the liver arteries increased in caliber and number.

DISCUSSION

The origin of the occlusion of the left portal vein is based on the adjustment to the postnatal hemodynamic situation in the umbilical recess. So far there is no evidence of the development of a permanent defect. For this reason and because of the possibility of spontaneous recanalization, treatment with anticoagulative drugs is hardly questioned.

CONCLUSION

Occlusion of the left portal vein is mostly an incidental finding. It may appear without catheterizing the umbilical vessel and might be a reason for the "idiopathic lack" of the left portal vein.