Scepter dual-lumen balloon catheter for Onyx embolization for dural arteriovenous fistula.

BACKGROUND: This study aimed to evaluate the efficacy and safety of Scepter dual-lumen balloon catheter for transarterial Onyx embolization of dural arteriovenous fistula (DAVF). METHODS: Transarterial Onyx embolization using a Scepter dual-lumen balloon catheter (Scepter-assisted Onyx embolization) for DAVF was attempted in a total of 35 patients (mean age, 52.5 years; M:F = 24:11) between October 2012 and December 2018. The results of Scepter-assisted Onyx embolization were evaluated with respect to total procedural and Onyx injection times, the types and number of feeders requiring embolization, angiographic and clinical outcomes, and treatment-related complications. RESULTS: Initial presentations were non-hemorrhagic neurological deficits in 10, intracranial hemorrhage in 8, seizure in 7, headache in 7, and intractable tinnitus in 3. All DAVF were aggressive type (Borden type 2, 14.3 %; type 3, 85.7 %). Scepter-assisted Onyx embolization resulted in immediately complete occlusion in 33 patients (94.3 %) and near complete occlusion in 2 patients. Middle meningeal artery (51.4 %) was the most commonly used for Scepter-assisted technique, followed by occipital artery (42.9 %), ascending pharyngeal artery (2.9 %) and superficial temporal artery (2.9 %). There was no difference in complete occlusion rate between middle meningeal artery and the other arteries (94.4 % versus 94.1 %). The median number of total feeders embolized was 1 (range, 1-3). The median total procedural time was 45 minutes (range, 21 minutes - 127 minutes) and the median Onyx injection time was 11 minutes (range, 3 minutes - 25 minutes). All patients recovered completely (n = 31) or partially (n = 4) from presenting symptoms. Treatment-related complications occurred in 2 patients, of whom one had a permanent morbidity (2.8 %, ipsilateral facial nerve palsy). No patient showed a recurrence on follow-up imaging (median, 15 months; range, 3-56 months). CONCLUSIONS: Scepter-assisted transarterial Onyx embolization showed a very high complete occlusion rate with a low morbidity and no recurrence in aggressive type DAVF. Scepter dual-lumen balloon catheter seems to be a useful tool for transarterial Onyx embolization of DAVF.

Comparison Between Perfusion- and Collateral-Based Triage for Endovascular Thrombectomy in a Late Time Window.

Background and Purpose- Perfusion-based triage has proven to be effective and safe for selecting patients who are likely to benefit from endovascular thrombectomy (EVT) in a late time window. We investigated collateral-based triage for EVT in patients presenting beyond 6 hours, in terms of interrater reliability and efficacy in predicting clinical outcome, in comparison to perfusion-based triage. Methods- One hundred and thirty-two patients who underwent both computed tomographic angiography and computed tomography perfusion for anterior circulation large artery occlusion 6 to 24 hours after last seen well were enrolled. Patients were classified into EVT-eligible and EVT-ineligible groups according to perfusion- and collateral-based triages. We evaluated the interrater reliability of collateral-based triage and differences in good outcome rates of patients who received EVT in the EVT-eligible groups based on perfusion- and collateral-based triages. Results- Both computed tomographic angiography and computed tomography perfusion were assessable in 93 patients. Seventy-six patients were eligible for EVT according to perfusion-based triage. Among them, EVT was performed in 58, of whom 32 (55.1%) had good outcome. Sixty-nine patients were eligible for EVT based on collateral-based triage. Among them, EVT was performed in 50 patients, of whom 31 (62.0%) had good outcome. Interrater reliability of collateral-based triage was good (generalized κ=0.73 [95% CI, 0.59-0.84]). Agreement on EVT eligibility between perfusion- and collateral-based triages was moderate (κ=0.41 [95% CI, 0.16-0.61]). There was no difference in good outcome rates of patients who underwent EVT in the EVT-eligible groups based on perfusion- and collateral-based triages (55.1% versus 62.0%; P=0.0675). Conclusions- Collateral-based triage showed good interrater reliability and comparable efficacy to that of perfusion-based triage in predicting clinical outcome after EVT in patients presenting beyond 6 hours. Collateral-based triage is a reliable approach for selecting patients for EVT in the extended therapeutic time window.

Mechanical Thrombectomy in Subtypes of Basilar Artery Occlusion: Relationship to Recanalization Rate and Clinical Outcome.

Background Acute stroke because of basilar artery occlusion (BAO) represents 1% of all ischemic strokes. However, recanalization rates and treatment outcome for the different pathologic subtypes of BAO stroke are not fully understood. Purpose To compare the recanalization rate and clinical outcomes of mechanical thrombectomy in different subtypes of BAO. Materials and Methods Eighty-two patients (46 men and 36 women; mean age, 73 years; age range, 20-90 years; mean age in men, 70 years [age range, 20-90 years]; mean age in women, 75 years [age range; 61-90 years]) with acute BAO who underwent mechanical thrombectomy between March 2010 and December 2017 were retrospectively analyzed. Patients were classified into three groups: embolism without vertebral artery (VA) steno-occlusion (group 1), embolism from tandem VA steno-occlusion (group 2), and in situ atherosclerotic thrombosis (group 3). Clinical and angiographic characteristics, recanalization rate, procedure times, and clinical outcomes were compared between groups by using the Kruskal-Wallis, Pearson χ2, and Fisher exact tests. Results The incidence of BAO according to stroke mechanism were as follows: group 1, n = 34 (41%); group 2, n = 28 (34%), group 3, n = 20 (24%). Overall, successful recanalization (modified Thrombolysis in Cerebral Infarction grade 2b or 3) was achieved in 78% (64 of 82) and favorable outcome (90-day modified Rankin Scale score, 0-2) in 37% (30 of 82) of the patients. The procedure time was shorter in group 1 than in group 2 (49 vs 66 minutes, respectively; P = .01). Group 1 showed a higher successful recanalization rate than group 3 (29 of 34 [85%] vs 11 of 20 [55%], respectively; P = .01). Good clinical outcome rate was higher in group 1 than in group 3 (18 of 34 [53%] vs four of 20 [20%], respectively; P = .02). Conclusion The outcome of mechanical thrombectomy for basilar artery occlusion differs according to the pathologic mechanism of stroke; the best outcomes and recanalization rate occurred in patients with embolism without vertebral artery steno-occlusion. © RSNA, 2019 See also the editorial by Hetts in this issue.

Prognostic Value of Cervical Nodal Necrosis Observed in Preoperative CT and MRI of Patients With Tongue Squamous Cell Carcinoma and Cervical Node Metastases: A Retrospective Study.

OBJECTIVE. The prognosis of tongue squamous cell carcinoma (SCC) with cervical lymph node metastases is poor, and a subset of patients with aggressive disease experiences treatment failure. The current study evaluated the prognostic value of cervical nodal necrosis (CNN) observed on preoperative imaging studies of patients with tongue SCC and cervical node metastases. MATERIALS AND METHODS. We identified patients with tongue SCC who had undergone preoperative neck CT or MRI (or both) and retrospectively reviewed their demographic and clinical data. Patients with metastatic cervical lymph nodes were divided into two groups according to the presence (CNN group) or absence (non-CNN group) of necrosis, and radiologic extranodal extension (ENE) was assessed for all patients. Follow-up biopsy, imaging, and clinical examinations were used to determine survival and treatment failure. Cox proportional hazard regression analyses were performed to determine clinical, demographic, and pathologic factors for survival. RESULTS. Seventy-two patients with a mean follow-up period of 28.4 months were included. The incidence of CNN was 55.6% (40/72). In univariate analysis, patient age, evidence of CNN on preoperative imaging, radiologic ENE, clinical N classification, and overall stage were significantly associated with survival. The multivariate Cox proportional hazard model showed that patient age and CNN on preoperative imaging were independent negative prognostic factors. CONCLUSION. CNN observed on preoperative imaging studies is an independent predictor of a poor prognosis for patients with tongue SCC, and it may serve as a useful imaging biomarker for tailoring individual treatment regimens.

Evaluation of glymphatic system activity using diffusion tensor image analysis along the perivascular space and amyloid PET in older adults with objectively normal cognition: a preliminary study.

Objectives: Diffusion tensor image analysis along the perivascular space (DTI-ALPS) is a recently introduced method for the assessment of the glymphatic system without the need for contrast injection. The purpose of our study was to assess the glymphatic system in cognitively normal older adults with or without subjective cognitive decline (SCD) using DTI-ALPS, and correlating with amyloid PET. Design and participants: To evaluate the glymphatic system in cognitively normal older adults using DTI-ALPS, we built a prospective cohort including a total of 123 objectively cognitively normal older adults with or without SCD. The ALPS index was calculated from DTI MRI and was assessed by correlating it with standardized uptake value ratios (SUVRs) from amyloid PET and clinically relevant variables. The study subjects were also divided into amyloid "positive" and "negative" groups based on the result of amyloid PET, and the ALPS indices between those two groups were compared. Results: The ALPS index was not significantly different between the normal and SCD groups (P = 0.897). The mean ALPS index from the amyloid positive and amyloid negative group was 1.31 and 1.35, respectively, which showed no significant difference (P = 0.308). Among the SUVRs from variable cortices, that of the paracentral cortex was negatively correlated with the ALPS index (r = -0.218, P = 0.016). Multivariate linear regression revealed that older age (coefficient, -0.007) and higher SUVR from the paracentral cortex (coefficient, -0.101) were two independent variables with a significant association with a lower ALPS index (P = 0.015 and 0.045, respectively). Conclusion: DTI-ALPS may not be useful for evaluation of the glymphatic system in subjects with SCD. Older age was significantly associated with lower ALPS index. Greater amyloid deposition in the paracentral cortex was significantly associated with lower glymphatic activity in cognitively normal older adults. These results should be validated in future studies on the relationships between ALPS index and other fundamental compartments in glymphatic system, such as perivenous space and the meningeal lymphatic vessels.

First-Pass Recanalization with EmboTrap II in Acute Ischemic Stroke (FREE-AIS): A Multicenter Prospective Study.

OBJECTIVE: We aimed to evaluate the efficacy of EmboTrap II in terms of first-pass recanalization and to determine whether it could yield favorable outcomes. MATERIALS AND METHODS: In this multicenter, prospective study, we consecutively enrolled patients who underwent mechanical thrombectomy using EmboTrap II as a front-line device. The primary outcome was the first pass effect (FPE) rate defined by modified Thrombolysis In Cerebral Infarction (mTICI) grade 2c or 3 by the first pass of EmboTrap II. In addition, modified FPE (mFPE; mTICI grade 2b-3 by the first pass of EmboTrap II), successful recanalization (final mTICI grade 2b-3), and clinical outcomes were assessed. We also analyzed the effect of FPE on a modified Rankin Scale (mRS) score of 0-2 at 3 months. RESULTS: Two hundred-ten patients (mean age ± standard deviation, 73.3 ± 11.4 years; male, 55.7%) were included. Ninety-nine patients (47.1%) had FPE, and mFPE was achieved in 150 (71.4%) patients. Successful recanalization was achieved in 191 (91.0%) patients. Among them, 164 (85.9%) patients underwent successful recanalization by exclusively using EmboTrap II. The time from groin puncture to FPE was 25.0 minutes (interquartile range, 17.0-35.0 minutes). Procedure-related complications were observed in seven (3.3%) patients. Symptomatic intracranial hemorrhage developed in 14 (6.7%) patients. One hundred twenty-three (58.9% of 209 completely followed) patients had an mRS score of 0-2. Sixteen (7.7% of 209) patients died during the follow-up period. Patients who had successful recanalization with FPE were four times more likely to have an mRS score of 0-2 than those who had successful recanalization without FPE (adjusted odds ratio, 4.13; 95% confidence interval, 1.59-10.8; p = 0.004). CONCLUSION: Mechanical thrombectomy using the front-line EmboTrap II is effective and safe. In particular, FPE rates were high. Achieving FPE was important for an mRS score of 0-2, even in patients with successful recanalization.

Combination of Rescue Stenting and Antiplatelet Infusion Improved Outcomes for Acute Intracranial Atherosclerosis-Related Large-Vessel Occlusion.

Background and Purpose: Intracranial atherosclerosis-related large-vessel occlusion caused by in situ thrombo-occlusion (ICAS-LVO) has been regarded an important reason for refractoriness to mechanical thrombectomy (MT). To achieve better outcomes for ICAS-LVO, different endovascular strategies should be explored. We aimed to investigate an optimal endovascular strategy for ICAS-LVO. Methods: We retrospectively reviewed three prospective registries of acute stroke underwent endovascular treatment. Among them, patients with ICAS-LVO were assigned to four groups based on their endovascular strategy: (1) MT alone, (2) rescue intracranial stenting after MT failure (MT-RS), (3) glycoprotein IIb/IIIa inhibitor infusion after MT failure (MT-GPI), and (4) a combination of MT-RS and MT-GPI (MT-RS+GPI). Baseline characteristics and outcomes were compared among the groups. To evaluate whether the endovascular strategy resulted in favorable outcome, multivariable analysis was also performed. Results: A total of 184 patients with ICAS-LVO were included. Twenty-four patients (13.0%) were treated with MT alone, 25 (13.6%) with MT-RS, 84 (45.7%) with MT-GPI, and 51 (27.7%) with MT-RS+GPI. The MT-RS+GPI group showed the highest recanalization efficiency (98.0%). Frequency of patent arteries on follow-up (98.0%, p < 0.001) and favorable outcome (84.3%, p < 0.001) were higher in the MT-RS+GPI group than other groups. The MT-RS+GPI strategy remained an independent factor for favorable outcome (odds ratio, 20.4; 95% confidence interval, 1.97-211.4; p = 0.012). Conclusion: Endovascular strategy was significantly associated with procedural and clinical outcomes in acute stroke by ICAS-LVO. A combination of RS and GPI infusion might be an optimal rescue modality when frontline MT fails.

[Endovascular Treatment of Acute Ischemic Stroke]. / 급성 허혈성 뇌졸중의 혈관 내 치료.

Acute ischemic stroke is one of the leading causes of disability and death around the world, especially in developed countries. Since the introduction of the 2nd generation devices, endovascular treatment of acute ischemic stroke has rapidly developed and is now considered to be a standard treatment. Here, we summarize the results of recent randomized clinical trials that have compared endovascular thrombectomy with conventional treatment for acute stroke and review the indications, current devices, and endovascular thrombectomy methods used.

Association between flat-panel computed tomography hyperattenuation and clinical outcome after successful recanalization by endovascular treatment.

OBJECTIVE: Hyperattenuation on CT scanning performed immediately after endovascular treatment (EVT) is known to be associated with the final infarct. As flat-panel CT (FPCT) scanning is readily accessible within their angiography suite, the authors evaluated the ability of the extent of hyperattenuation on FPCT to predict clinical outcomes after EVT. METHODS: Patients with successful recanalization (modified Thrombolysis in Cerebral Infarction grade 2b or 3) were reviewed retrospectively. The extent of hyperattenuation was assessed by the Alberta Stroke Program Early CT Score on FPCT (FPCT-ASPECTS). FPCT-ASPECTS findings were compared according to functional outcome and malignant infarction. The predictive power of the FPCT-ASPECTS with initial CT images before EVT (CT-ASPECTS) and follow-up diffusion-weighted images (MR-ASPECTS) was also compared. RESULTS: A total of 235 patients were included. All patients were treated with mechanical thrombectomy, and 45.5% of the patients received intravenous tissue plasminogen activator. The mean (± SD) time from stroke onset to recanalization was 383 ± 290 minutes. The FPCT-ASPECTS was significantly different between patients with a favorable outcome and those without (mean 9.3 ± 0.9 vs 6.7 ± 2.6) and between patients with malignant infarction and those without (3.4 ± 2.9 vs 8.8 ± 1.4). The FPCT-ASPECTS was an independent factor for a favorable outcome (adjusted OR 3.28, 95% CI 2.12-5.01) and malignant infarction (adjusted OR 0.42, 95% CI 0.31-0.57). The area under the curve (AUC) of the FPCT-ASPECTS for a favorable outcome (0.862, cutoff ≥ 8) was significantly greater than that of the CT-ASPECTS (0.637) (p < 0.001) and comparable to that of the MR-ASPECTS (0.853) (p = 0.983). For malignant infarction, the FPCT-ASPECTS was also more predictive than the CT-ASPECTS (AUC 0.906 vs 0.552; p = 0.001) with a cutoff of ≤ 5. CONCLUSIONS: The FPCT-ASPECTS was highly predictive of clinical outcomes in patients with successful recanalization. FPCT could be a practical method to immediately predict clinical outcomes and thereby aid in acute management after EVT.

Predictors of Good Outcomes in Patients with Failed Endovascular Thrombectomy.

OBJECTIVE: Endovascular thrombectomy (EVT) fails in approximately 20% of anterior circulation large vessel occlusion (AC-LVO). Nonetheless, the factors that affect clinical outcomes of non-recanalized AC-LVO despite EVT are less studied. The purpose of this study was to identify the factors affecting clinical outcomes in non-recanalized AC-LVO patients despite EVT. MATERIALS AND METHODS: This was a retrospective analysis of clinical and imaging data from 136 consecutive patients who demonstrated recanalization failure (modified thrombolysis in cerebral ischemia [mTICI], 0-2a) despite EVT for AC-LVO. Data were collected in prospectively maintained registries at 16 stroke centers. Collateral status was categorized into good or poor based on the CT angiogram, and the mTICI was categorized as 0-1 or 2a on the final angiogram. Patients with good (modified Rankin Scale [mRS], 0-2) and poor outcomes (mRS, 3-6) were compared in multivariate analysis to evaluate the factors associated with a good outcome. RESULTS: Thirty-five patients (25.7%) had good outcomes. The good outcome group was younger (odds ratio [OR], 0.962; 95% confidence interval [CI], 0.932-0.992; p = 0.015), had a lower incidence of hypertension (OR, 0.380; 95% CI, 0.173-0.839; p = 0.017) and distal internal carotid artery involvement (OR, 0.149; 95% CI, 0.043-0.520; p = 0.003), lower initial National Institute of Health Stroke Scale (NIHSS) (OR, 0.789; 95% CI, 0.713-0.873; p < 0.001) and good collateral status (OR, 13.818; 95% CI, 3.971-48.090; p < 0.001). In multivariate analysis, the initial NIHSS (OR, 0.760; 95% CI, 0.638-0.905; p = 0.002), good collateral status (OR, 14.130; 95% CI, 2.264-88.212; p = 0.005) and mTICI 2a recanalization (OR, 5.636; 95% CI, 1.216-26.119; p = 0.027) remained as independent factors with good outcome in non-recanalized patients. CONCLUSION: Baseline NIHSS score, good collateral status, and mTICI 2a recanalization remained independently associated with clinical outcome in non-recanalized patients. mTICI 2a recanalization would benefit patients with good collaterals in non-recanalized AC-LVO patients despite EVT.

Coil-Protected Technique for Liquid Embolization in Neurovascular Malformations.

OBJECTIVE: To evaluate the safety and efficacy of the coil-protected technique for liquid embolization in neurovascular malformations. MATERIALS AND METHODS: Twenty-two patients who underwent coil-protected liquid embolization for symptomatic cranial (n = 13) and spinal (n = 9) arteriovenous fistula (AVF) or arteriovenous malformations (AVMs) were identified. A total of 36 target feeder vessels were embolized with N-butyl cyanoacrylate and/or Onyx (Medtronic). This technique was used to promote delivery of a sufficient amount of liquid embolic agent into the target shunt or nidus in cases where tortuous feeding arteries preclude a microcatheter wedging techniqu and/or to prevent reflux of the liquid embolic agent in cases with a short safety margin. The procedure was considered technically successful if the target lesion was sufficiently filled with liquid embolic agent without unintentional reflux. Angiographic and clinical outcomes were retrospectively evaluated. RESULTS: Technical success was achieved for all 36 target feeders. Post-embolization angiographies revealed complete occlusion in 16 patients and near-complete and partial occlusion in three patients each. There were no treatment-related complications. Of the six patients who showed near-complete or partial occlusion, five received additional treatments: two received stereotactic radiosurgery for cerebral AVM, two underwent surgical removal of cerebral AVM, and one underwent additional embolization by direct puncture for a mandibular AVM. Finally, all patients showed complete (n = 19) or near-complete (n = 3) occlusion of the target AVF or AVM on follow-up angiographies. The presenting neurological symptoms improved completely in 15 patients (68.2%) and partially in seven patients (31.8%). CONCLUSION: The coil-protected technique is a safe and effective method for liquid embolization, especially in patients with various neurovascular shunts or malformations who could not be successfully treated with conventional techniques.

Radiation dose reduction and image quality in pediatric abdominal CT with kVp and mAs modulation and an iterative reconstruction technique.

OBJECTIVE: The objective of this study was to compare the radiation dose and image quality of pediatric abdominal computed tomography (CT) using a protocol reconstructed with filtered back projection (FBP) and a protocol with both kVp and mAs modulation and sinogram-affirmed iterative reconstruction (SAFIRE). MATERIALS AND METHODS: We retrospectively reviewed pediatric abdominal CT examinations performed with both kVp and mAs modulation. These raw data were reconstructed with SAFIRE at different strengths from 2 to 4 (SAFIRE groups 2-4). Another set of age/sex-matched pediatric abdominal CT examinations were also reviewed, which were performed during the same period with only mAs modulation and FBP (control group). The radiation dose and image quality were compared between groups. The image quality was objectively evaluated as the noise measured in the liver, aorta, and spleen at the level of the main portal vein and the image quality was subjectively reviewed by two radiologists for diagnostic acceptability using a four-point scale (0: unacceptable; 1: worse than the control group, but acceptable; 2: comparable with the control group; and 3: better than the control group). An independent t test was used in order to compare the radiation dose. An independent t test with Bonferroni correction and generalized estimating equations were used for the comparison of the objective and subjective image quality, respectively. RESULTS: Twenty-nine patients (M:F=19:10; mean age, 10.0 years) were enrolled in each group. The SAFIRE group, using the size-specific dose estimates calculation method showed a 64.2% radiation dose reduction (from 8.1 to 2.9 mGy, P<.05), compared with the results of the control group. The objective image noise of the SAFIRE groups 2 and 3 was comparable to that of the control group. The subjective image quality was the best in SAFIRE group 3 [odds ratio (OR) 3.015, P<.001 when comparing to SAFIRE group 0; OR 1.513, P<.001 when comparing to SAFIRE group 2]. CONCLUSIONS: Image acquisition with both kVp and mAs modulation and iterative reconstruction using SAFIRE with strength 3 can preserve the objective and subjective image quality of pediatric abdominal CT scans with less than half the radiation dose.

Length and volume of morphologically normal kidneys in korean children: ultrasound measurement and estimation using body size.

OBJECTIVE: To evaluate the relationship between anthropometric measurements and renal length and volume measured with ultrasound in Korean children who have morphologically normal kidneys, and to create simple equations to estimate the renal sizes using the anthropometric measurements. MATERIALS AND METHODS: We examined 794 Korean children under 18 years of age including a total of 394 boys and 400 girls without renal problems. The maximum renal length (L) (cm), orthogonal anterior-posterior diameter (D) (cm) and width (W) (cm) of each kidney were measured on ultrasound. Kidney volume was calculated as 0.523 × L × D × W (cm(3)). Anthropometric indices including height (cm), weight (kg) and body mass index (m(2)/kg) were collected through a medical record review. We used linear regression analysis to create simple equations to estimate the renal length and the volume with those anthropometric indices that were mostly correlated with the US-measured renal sizes. RESULTS: Renal length showed the strongest significant correlation with patient height (R(2), 0.874 and 0.875 for the right and left kidneys, respectively, p < 0.001). Renal volume showed the strongest significant correlation with patient weight (R(2), 0.842 and 0.854 for the right and left kidneys, respectively, p < 0.001). The following equations were developed to describe these relationships with an estimated 95% range of renal length and volume (R(2), 0.826-0.884, p < 0.001): renal length = 2.383 + 0.045 × Height (± 1.135) and = 2.374 + 0.047 × Height (± 1.173) for the right and left kidneys, respectively; and renal volume = 7.941 + 1.246 × Weight (± 15.920) and = 7.303 + 1.532 × Weight (± 18.704) for the right and left kidneys, respectively. CONCLUSION: Scatter plots between height and renal length and between weight and renal volume have been established from Korean children and simple equations between them have been developed for use in clinical practice.