High plasma BNP concentration associates with clinical outcome after mechanical thrombectomy: Post hoc analysis of SKIP.

OBJECTIVES: Heart failure may result in reduced brain perfusion, limiting the blood flow needed to achieve clinical recovery. We investigated whether plasma levels of brain natriuretic peptide (BNP), a biological marker of heart failure, were related to clinical outcomes after mechanical thrombectomy (MT). MATERIALS AND METHODS: Data were analyzed from stroke patients with internal carotid or middle cerebral artery occlusion enrolled in the SKIP trial for whom plasma level of BNP was evaluated on admission. Favorable outcome was defined as a modified Rankin scale score of 0-2 at 3 months. RESULTS: Among 169 patients (median age, 74 years; 62% men, median National Institutes of Health Stroke Scale score, 18), 104 (62%) achieved favorable outcomes. Median plasma BNP level was lower in the favorable outcome group (124.1 pg/mL; interquartile range [IQR], 62.1-215.5 pg/mL) than in the unfavorable outcome group (198.0 pg/mL; IQR, 74.8-334.0 pg/mL; p=0.005). In multivariate regression analysis, the adjusted odds ratio for BNP for favorable outcomes was 0.971 (95% confidence interval, 0.993-0.999; p=0.048). At 3 months after onset, the favorable outcome rate was lower in the ≥186 pg/mL group (45%) than in the <186 pg/mL group (72%; p=0.001). This significant difference remained regardless of the presence of atrial fibrillation (AF), with rates of 47% and 76%, respectively, in AF patients (p=0.003) and 33% and 68%, respectively, in patients without AF (p=0.046). CONCLUSION: High plasma BNP concentration appears associated with unfavorable outcomes after MT.

Radiation dose analysis in interventional neuroradiology of unruptured aneurysm cases.

This study aimed to evaluate the radiation doses (peak skin dose (PSD) and bilateral lens dose) for each interventional neuroradiology procedure. A direct measurement system consisting of small radiophotoluminescence glass dosimeter chips and a dosimetry cap made of thin stretchable polyester was used for radiation dosimetry. The mean PSDs for each procedure were 1565 ± 590 mGy (simple technique coil embolization (STCE) cases), 1851 ± 825 mGy (balloon-assisted coil embolization (BACE) cases), 2583 ± 967 mGy (stent-assisted coil embolization (SACE) cases), 1690 ± 597 mGy (simple flow-diverter stenting (FDS) cases), and 2214 ± 726 mGy (FDS + coiling cases). The mean PSD was higher in SACE cases than in STCE, BACE, and simple FDS cases. Moreover, the PSD exceeded 2000 mGy and 3000 mGy in 46 (67.6%) and 19 (27.9%) SACE cases, respectively. The left lens doses for each procedure were 126 ± 111 mGy (STCE cases), 163 ± 152 mGy (BACE cases), 184 ± 148 mGy (SACE cases), 144 ± 60 mGy (simple FDS cases), and 242 ± 178 mGy (FDS + coiling cases). The left lens dose in SACE cases was higher than that in STCE cases and exceeded 500 mGy in 3 (4.4%) patients. In FDS + coiling cases, the mean PSD and left lens dose were 2214 ± 726 mGy and 242 ± 178 mGy, respectively. The left lens dose was higher than that in the STCE and BACE cases, with two (15.4%) patients receiving doses >500 mGy in FDS + coiling cases. The detailed data obtained in this study are expected to contribute to the promotion of radiation dose optimization.

[Posterior Communicating Artery / Posterior Cerebral Artery].

Thorough understanding of the vascular anatomy, including embryological development of vessels is important to safely perform endovascular procedures. The posterior cerebral and anterior choroidal arteries are embryologically complementary, which suggests a potential network. Numerous perforators originate from the posterior communicating and posterior cerebral arteries. The tuberothalamic artery arising from the posterior communicating artery and the thalamoperforating artery, which originates from the P1 segment of the posterior cerebral artery are clinically important because occlusion of these vessels can precipitate severe infarction. It is clinically important to be aware that the branching pattern of perforators differs based on the fusion type of the basilar tip. The balloon occlusion and Allcock test are useful to predict ischemic tolerance in cases of intentional artery occlusion. However, accurate prediction remains challenging, and a definitive evaluation method is unavailable. Flow disturbances in the cortical territory and local perforator impairment require close attention in cases of intentional artery occlusion.

Comparison of the Clinical Outcome of Carotid Artery Stenting Between Institutions With a Treatment Strategy Based on Risk Factors and Those With First-Line Treatment.

PURPOSE: Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are recommended based on certain risk factors. The volume of an institution's treatment experience may be associated with good clinical outcomes. There is a dilemma between the treatment strategy based on risk factors and the experience volume. Therefore, we investigated the clinical outcomes of CAS performed at institutions that selected the treatment strategy based on risk factors and those that performed CAS at the first-line treatment. MATERIALS AND METHODS: Patients who underwent CAS at 5 institutions were included in this retrospective case-control study. We defined CEA/CAS institutions as those that selected the treatment option based on risk factors, and CAS-first institutions as those that performed CAS as the first-line treatment. We investigated cases of ischemic stroke, hemorrhagic stroke, myocardial infarction, and deaths within 30 days of the intervention between the CEA/CAS- and CAS-first institution groups. One-to-one propensity score matching was performed to compare rates of ischemic and hemorrhagic strokes within 30 days of the intervention. RESULTS: A total of 239 and 302 patients underwent CAS at the CEA/CAS institutions and CAS-first institutions, respectively; ischemic stroke occurred in 12 (5.0%) and 7 patients (2.3%), respectively (p=0.09). No differences in major ischemic strokes (0.8% vs 1.3%; p=0.59), hemorrhagic strokes (0.4% vs 0.3%; p=0.87), or deaths (0.0% vs 0.7%; p=0.21) were observed. Myocardial infarction did not occur in either group. Propensity score analysis showed that ischemic stroke (odds ratio: 1.845, 95% confidence interval: 0.601-5.668, p=0.28) and hemorrhagic stroke (odds ratio: 1.000, 95% confidence interval: 0.0061-16.418, p=1.00) were not significantly associated with either institution group. CONCLUSIONS: The CAS-specific treatment strategies for CAS can achieve the same level of outcomes as the treatment strategy based on risk factors. The CAS performed based on risk factors in CEA/CAS institutions and the treatment of more than 30 patients/year/institution in CAS-first institutions were associated with good clinical outcomes.

Delineability and anatomical variations of perforating arteries from normal vertebral artery on 3D DSA: implications for endovascular treatment of dissecting aneurysms.

BACKGROUND AND PURPOSE: Endovascular trapping of the vertebral artery dissecting aneurysms (VADAs) carries a risk of medullary infarction due to the occlusion of the perforating arteries. We evaluated the detectability and anatomical variations of perforating arteries arising from the vertebral artery (VA) using three-dimensional DSA. METHODS: In 120 patients without VA lesions who underwent rotational vertebral arteriography, the anatomical configurations of perforating arteries from the VA were retrospectively evaluated on the bi-plane DSA and reconstructed images to reach the consensus between two experienced reviewers. The images were interpreted by focusing on the numbers and types of perforating arteries, the relationships between the number of perforators and the anatomy of the VA and its branches. RESULTS: Zero, 1, 2, 3, 4, and 6 perforators were detected in 2, 51, 56, 9, 1, and 1 patient, respectively (median of 2 perforators per VA). The 200 perforators were classified into 146 terminal and 54 longitudinal course types and into 32 ventral, 151 lateral, and 17 dorsolateral distribution types. All ventral type perforators were also terminal type. In contrast, the longitudinal type was seen in 28.5% of lateral types and in 65% of dorsolateral types. Regarding the difference in the origin of the posterior inferior cerebellar artery (PICA), non-PICA type VAs gave off larger number of perforators than the other types of VAs. CONCLUSIONS: Non-PICA type VAs give off a significantly larger number of perforators than other types, indicating that the trapping of non-PICA type VAs is associated with a risk of ischemic complications.

Risk factors for medullary infarction after endovascular trapping of vertebral artery dissecting aneurysms.

Internal trapping (IT) is a treatment option for intracranial vertebral artery dissecting aneurysms (VADAs). Medullary infarction (MI) is a complication linked to this treatment. This study aims to clarify the outcomes of IT for VADAs and the risk factors for MIs. We retrospectively reviewed the databases from 2010 to 2017 to identify patients with VADAs treated by IT at seven collaborating institutions. Radiological findings, clinical courses, and outcomes were analyzed. Perforating arteries were classified into terminal or longitudinal types using preoperative angiography. IT was completed in 90 patients (74 ruptured and 16 unruptured VADA). Postoperative rebleeding did not occur in any ruptured VADA patients. Postoperative MRI detected MIs in 26 patients (28.9%). The incidence of MIs in the ruptured VADA (32%) was higher compared with that in the unruptured VADA (13%), though it was not significant. In the MI group, the occlusion or blind alley of the terminal-type and longitudinal-type perforator was confirmed in 23 patients (88%) and 11 patients (42%), respectively. The occlusion or blind alley of the terminal-type perforator was an independent risk factor for MIs in the logistic regression analysis (OR 5.81; 95% CI 1.34-25.11; p = 0.018). In ruptured VADA, postoperative MI (OR 12.2; 95% CI 3.19-64.55; p = 0.0001) and high-grade SAH (OR 8.02; 95% CI 2.32-37.70; p = 0.0006) were independent risk factors of an unfavorable clinical outcome. In conclusion, MIs were an independent risk factor for unfavorable outcomes after IT, especially for a ruptured VADA. The occlusion or blind alley of the terminal-type perforator caused by the IT was associated with postoperative MIs.

Effect of Mechanical Thrombectomy Without vs With Intravenous Thrombolysis on Functional Outcome Among Patients With Acute Ischemic Stroke: The SKIP Randomized Clinical Trial.

IMPORTANCE: Whether intravenous thrombolysis is needed in combination with mechanical thrombectomy in patients with acute large vessel occlusion stroke is unclear. OBJECTIVE: To examine whether mechanical thrombectomy alone is noninferior to combined intravenous thrombolysis plus mechanical thrombectomy for favorable poststroke outcome. DESIGN, SETTING, AND PARTICIPANTS: Investigator-initiated, multicenter, randomized, open-label, noninferiority clinical trial in 204 patients with acute ischemic stroke due to large vessel occlusion enrolled at 23 hospital networks in Japan from January 1, 2017, to July 31, 2019, with final follow-up on October 31, 2019. INTERVENTIONS: Patients were randomly assigned to mechanical thrombectomy alone (n = 101) or combined intravenous thrombolysis (alteplase at a 0.6-mg/kg dose) plus mechanical thrombectomy (n = 103). MAIN OUTCOMES AND MEASURES: The primary efficacy end point was a favorable outcome defined as a modified Rankin Scale score (range, 0 [no symptoms] to 6 [death]) of 0 to 2 at 90 days, with a noninferiority margin odds ratio of 0.74, assessed using a 1-sided significance threshold of .025 (97.5% CI). There were 7 prespecified secondary efficacy end points, including mortality by day 90. There were 4 prespecified safety end points, including any intracerebral hemorrhage and symptomatic intracerebral hemorrhage within 36 hours. RESULTS: Among 204 patients (median age, 74 years; 62.7% men; median National Institutes of Health Stroke Scale score, 18), all patients completed the trial. Favorable outcome occurred in 60 patients (59.4%) in the mechanical thrombectomy alone group and 59 patients (57.3%) in the combined intravenous thrombolysis plus mechanical thrombectomy group, with no significant between-group difference (difference, 2.1% [1-sided 97.5% CI, -11.4% to ∞]; odds ratio, 1.09 [1-sided 97.5% CI, 0.63 to ∞]; P = .18 for noninferiority). Among the 7 secondary efficacy end points and 4 safety end points, 10 were not significantly different, including mortality at 90 days (8 [7.9%] vs 9 [8.7%]; difference, -0.8% [95% CI, -9.5% to 7.8%]; odds ratio, 0.90 [95% CI, 0.33 to 2.43]; P > .99). Any intracerebral hemorrhage was observed less frequently in the mechanical thrombectomy alone group than in the combined group (34 [33.7%] vs 52 [50.5%]; difference, -16.8% [95% CI, -32.1% to -1.6%]; odds ratio, 0.50 [95% CI, 0.28 to 0.88]; P = .02). Symptomatic intracerebral hemorrhage was not significantly different between groups (6 [5.9%] vs 8 [7.7%]; difference, -1.8% [95% CI, -9.7% to 6.1%]; odds ratio, 0.75 [95% CI, 0.25 to 2.24]; P = .78). CONCLUSIONS AND RELEVANCE: Among patients with acute large vessel occlusion stroke, mechanical thrombectomy alone, compared with combined intravenous thrombolysis plus mechanical thrombectomy, failed to demonstrate noninferiority regarding favorable functional outcome. However, the wide confidence intervals around the effect estimate also did not allow a conclusion of inferiority. TRIAL REGISTRATION: umin.ac.jp/ctr Identifier: UMIN000021488.

[Dissecting Internal Carotid Aneurysm Causing Epistaxis:A Case Report].

We report a rare case of a ruptured dissecting internal carotid aneurysm caused epistaxis without a history of trauma or infection. An 89-year-old woman experienced epistaxis and suffered from hemorrhagic shock at her previous hospital. Head computed tomography(CT)images revealed a ruptured internal carotid aneurysm protruding into the Onodi cell, the most posterior ethmoidal sinus, which extends superolaterally to the sphenoid sinus. Cerebral angiography demonstrated a multilobular-shaped dissecting aneurysm with a maximal diameter of 6.7mm at the cavernous portion of the internal carotid artery(ICA). Overlapping stenting was performed to prevent recanalization. However, a fatal subarachnoid hemorrhage occurred 2 days after the procedure due to the progression of the dissection to the intracranial ICA. The anatomical characteristics of the ethmoidal sinus could be associated with the occurrence of epistaxis. A ruptured small ICA aneurysm with an Onodi cell might cause epistaxis without a history of trauma or infection.

Neurovascular Unit Protection From Cerebral Ischemia-Reperfusion Injury by Radical-Containing Nanoparticles in Mice.

BACKGROUND AND PURPOSE: Reperfusion therapy by mechanical thrombectomy is used to treat acute ischemic stroke. However, reactive oxygen species generation after reperfusion therapy causes cerebral ischemia-reperfusion injury, which aggravates cerebral infarction. There is limited evidence for clinical efficacy in stroke for antioxidants. Here, we developed a novel core-shell type nanoparticle containing 4-amino-4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (nitroxide radical-containing nanoparticles [RNPs]) and investigated its ability to scavenge reactive oxygen species and confer neuroprotection. METHODS: C57BL/6J mice underwent transient middle cerebral artery occlusion and then received RNPs (9 mg/kg) through the common carotid artery. Infarction size, neurological scale, and blood-brain barrier damage were visualized by Evans blue extravasation 24 hours after reperfusion. RNP distribution was detected by rhodamine labeling. Blood-brain barrier damage, neuronal apoptosis, and oxidative neuronal cell damage were evaluated in ischemic brains. Multiple free radical-scavenging capacities were analyzed by an electron paramagnetic resonance-based method. RESULTS: RNPs were detected in endothelial cells and around neuronal cells in the ischemic lesion. Infarction size, neurological scale, and Evans blue extravasation were significantly lower after RNP treatment. RNP treatment preserved the endothelium and endothelial tight junctions in the ischemic brain; neuronal apoptosis, O2- production, and gene oxidation were significantly suppressed. Reactive oxygen species scavenging capacities against OH, ROO, and O2- improved by RNP treatment. CONCLUSIONS: An intra-arterial RNP injection after cerebral ischemia-reperfusion injury reduced blood-brain barrier damage and infarction volume by improving multiple reactive oxygen species scavenging capacities. Therefore, RNPs can provide neurovascular unit protection.

Early retreatment after surgical clipping of ruptured intracranial aneurysms.

BACKGROUND: Although a rerupture after surgical clipping of ruptured intracranial aneurysms is rare, it is associated with high morbidity and mortality. The causes for retreatment and rupture after surgical clipping are not clearly defined. METHODS: From a prospectively maintained database of 244 patients who had undergone surgical clipping of ruptured intracranial aneurysms, we selected patients who experienced retreatment or rerupture within 30 days after surgical clipping. Aneurysm occlusions were examined by microvascular Doppler ultrasonography and indocyanine green video-angiography. Indications for retreatment included rerupture and partial occlusion. We analyzed the characteristics and causes of early retreatment. RESULTS: Six patients (2.5%, 95% CI 0.9 to 5.3%) were retreated within 30 days after surgical clipping, including two patients (0.8%, 95% CI 0.1 to 2.9%) who experienced a rerupture. The retreated aneurysms were found in the anterior communicating artery (AcomA) (n = 5) and basilar artery (n = 1). Retreatment of the AcomA (7.5%) was performed significantly more frequently than that of other arteries (0.56%) (p < 0.01). A laterally projected AcomA aneurysm (17.4%) was more frequently retreated than were other aneurysm types (2.3%). Cases of laterally projecting AcomA aneurysms tended to result from an incomplete clip placed using a pterional approach from the opposite side of the aneurysm projection. CONCLUSIONS: Despite developments, the rates of retreatment and rerupture after surgical clipping remain similar to those reported previously. Retreatment of the AcomA was significantly more frequent than was retreatment of other arteries. Patients underwent retreatment more frequently when they were originally treated for lateral type aneurysms using a pterional approach from the opposite side of the aneurysm projection. The treatment method and evaluation modalities should be considered carefully for AcomA aneurysms in particular.

[Dural Arteriovenous Fistula with Acute Visual Loss Manifestation:A Case Report].

In this report, we are describing a rare case of dural arteriovenous fistula(DAVF)followed by an isolated symptom of bilateral visual acuity disturbance. The patient was a 67-year-old man suffering from progressive bilateral visual acuity disturbance. Angiography revealed a diffuse arteriovenous fistula in the left transverse-sigmoid sinus affected by severe venous congestion. Visual acuity disturbance is likely to have been caused by increased intracranial pressure(IICP). Venous congestion as well as visual acuity were gradually improved following three transarterial embolizations. It is possible that a gradual progression of the clinical condition has caused only visual acuity disturbance without any other IICP symptoms, which is similar to pseudotumor cerebri. Should an unexplained visual acuity loss occur, the case should be investigated by considering DAVF.

[A Case of Traumatic Carotid Cavernous Fistula Treated with a Single Procedure Selective Transarterial Embolization Using Hydrogel Coils].

A 30-year-old man was admitted to our hospital after a bicycle accident. Proptosis, conjunctival congestion, and orbital vascular bruit appeared one month after the accident. Neuroradiological findings showed a traumatic carotid cavernous fistula(CCF). CCF is a pathologic arteriovenous shunt between the carotid artery and cavernous sinus. A detachable balloon was the standard device used for treatment of high flow direct CCF, although it is currently unavailable in Japan. Therefore, many other constructive strategies are being developed. We successfully treated this patient with single transarterial embolization using hydrogel coils. Hydrogel coils are platinum coils coated with polymeric water gels, and can be used at a prospect of delayed volume expansion. In our case, the patency of the internal carotid artery was maintained using the coils, and the symptoms improved shortly after the procedure. The use of hydrogel coils for the treatment of CCF appears to be safe and effective.

Emergence of the white-collar sign after coil embolization of cerebral aneurysms.

BACKGROUND: The white-collar sign (WCS) is represented by the formation of neointimal tissue at the level of the aneurysm neck as the successful outcome on follow-up angiography after coil embolization. WCS has been reported only in aneurysms treated with Matrix® coils. This is the first study to report WCS emergence in aneurysms treated with bare platinum coils, and potential factors associated with WCS emergence were evaluated. METHOD: Total 130 unruptured (female: male ratio, 100: 30; mean age, 60 years) cerebral aneurysms were treated with coil embolization. Embolization status was assessed immediately and 1 year after treatment, and emergence of WCS in follow-up angiography was assessed. We evaluated the association between WCS emergence and aneurysm location, dome diameter, neck diameter, dome-neck ratio, and type of coil used (bare platinum or bioactive). RESULTS: WCS appeared in nine aneurysms (6.9%), of which six were treated only with bare platinum coils. Neck diameter was significantly smaller in the WCS-positive group than in the WCS-negative group. The proportion of aneurysms treated with bioactive coils was not significantly different between the groups. Immediate embolization status in the WCS-positive group tended to be slightly better than that in the WCS-negative group. No aneurysmal morphological characteristics other than small neck diameter were associated with WCS emergence. CONCLUSIONS: WCS is not specific to bioactive coil usage. Small neck diameter was significantly associated with WCS emergence in our series. Further investigations to clarify the predictors of WCS will contribute to progress of aneurysmal embolization.

Ophthalmic artery originating from contralateral internal carotid artery associated with ipsilateral agenesis of internal carotid artery.

Congenital absence of the internal carotid artery is a rare anatomical variant. The primarily reported origins of the ophthalmic artery associated with this variant are the posterior communicating, middle cerebral, and external carotid arteries. We report the case of a patient without an internal carotid artery whose ophthalmic artery originated from the contralateral internal carotid artery. The superior hypophyseal and prechiasmal arteries may contribute to collateral flow to the orbit from the contralateral internal carotid artery.

Additional outlet occlusion as an important factor in avoiding retreatment after transvenous embolization for cavernous sinus dural arteriovenous fistulas.

BACKGROUND: Transvenous embolization (TVE), such as selective shunt occlusion, is the first line treatment for cavernous sinus dural arteriovenous fistula (CSDAVF). Despite the favorable outcomes of TVE, some cases necessitating retreatment due to recurrence or incomplete occlusion persist. Given the physical, psychological, and financial burden of multiple treatments, understanding the predictive factors for recurrence, spontaneous occlusion, or retreatment is important. However, few reports have addressed these factors, complicating decision making regarding the need for retreatment. This study analyzed predictive factors for retreatment and spontaneous occlusion to offer new insights into CSDAVF management. METHODS: This retrospective, observational study was conducted in two acute care hospitals. Patients aged 18-100 years undergoing endovascular treatment for CSDAVF from January 2011 to December 2022 were included. RESULTS: Of 65 patients treated with TVE, 29 experienced immediate complete occlusion. Meanwhile, 22 of 36 patients with incomplete occlusion had spontaneous occlusion, and retreatment was performed in 20% of patients. Additional outlet occlusion was negatively associated with retreatment (P=0.046), and it tended to promote spontaneous occlusion (P=0.056). Favorable functional outcomes were observed in all patients, and approximately 94% of patients showed complete occlusion at the latest follow-up. CONCLUSION: TVE is an effective treatment for CSDAVF. Outlet occlusion, when immediate complete occlusion is unattainable, is important to reduce retreatment and promote spontaneous occlusion. Substantially reducing shunt flow, carefully assessing dangerous drainage routes, and closely monitoring the residual shunt are crucial for preventing intracranial hemorrhage when outlet occlusion is performed.

Anatomical Flow Diversion by Hybrid Strategy for Intractable Large Cerebral Aneurysms.

BACKGROUND AND IMPORTANCE: Flow diverters (FDs) provide curative endovascular treatment for wide-necked sidewall aneurysms. The efficacy of FDs for bifurcation or branching sidewall aneurysms is probably limited. We used anatomical flow diversion (AFD) for intractable large cerebral aneurysms. We report our experiences with AFD. METHODS: The concept of AFD is the transformation from the bifurcation or branching sidewall type to the nonbranching sidewall type. Linearization of the parent artery by stenting, intentional branch occlusion, and aneurysmal coil embolization were performed. Furthermore, bypass surgery is performed for patients intolerant to branch occlusions. We evaluated the clinical outcomes of intractable aneurysms treated with AFD. RESULTS: AFD was performed in seven unruptured large aneurysms. Aneurysmal locations were the top of the basilar artery (BA), BA-superior cerebellar artery (SCA), internal carotid artery (IC)-posterior communicating artery (PcomA), and IC terminal. The mean dome diameter was 17.0 ± 4.6 mm. Six patients underwent bypass surgery. The occluded branches were the PCA + SCA, PcomA, and anterior cerebral artery (ACA) A1. An FD was used in three patients and a neck bridge stent in four patients. No intraprocedural complications occurred. Two postprocedural ischemic complications occurred in one patient. Six (86%) patients demonstrated a modified Rankin Scale (mRS) 0 at the 3-month follow-up, and one with an ischemic complication showed an mRS 5. Complete occlusion of all aneurysms was maintained with a median follow-up duration of 60 months. CONCLUSION: AFD is useful for intractable large cerebral aneurysms with high curability, although safety verification is required.

Efficacy and Safety of Lumbar Drainage before Endovascular Treatment for Ruptured Intracranial Aneurysms.

Objective: Intraoperative rebleeding during endovascular treatment for ruptured intracranial aneurysms is associated with poor prognosis. Lumbar drainage is performed preoperatively to control intracranial pressure; however, it is associated with a risk of brain herniation or rebleeding because intracranial pressure may change rapidly. Therefore, this study aimed to examine the efficacy and safety of preoperative lumbar drainage. Methods: This retrospective study enrolled 375 patients who underwent endovascular treatment of ruptured intracranial aneurysms at our institution between April 2013 and March 2018. The incidence of rebleeding and clinical outcomes were compared between patients who did and did not undergo preoperative lumbar drainage. Results: Among the 375 patients with ruptured intracranial aneurysms, 324 (86.0%) and 51 (14.0%) patients did and did not undergo lumbar drainage, respectively. The incidence of rebleeding was 11/324 (3.4%) and 2/51 (3.9%) in lumbar drainage and nonlumbar drainage groups, respectively, with no statistical differences (p = 0.98). Of the rebleeding cases, 9/11 (81%) and 2/2 (100%) in lumbar drainage and nonlumbar drainage groups, respectively, were due to intraoperative bleeding, and 2/11 (19%) in the lumbar drainage group, the causes of the rebleeding were undetermined. The incidence of symptomatic vasospasm did not differ significantly between the groups (13.2% vs. 11.8%, P = 0.776), while the incidence of hydrocephalus (24.6% vs. 11.8%, P = 0.043) and meningitis (15.2% vs. 5.9%, P = 0.075) were slightly higher in the lumbar drainage group. Favorable clinical outcomes (modified Rankin Scale score <2) at discharge were less frequent in the lumbar drainage group (55.3% vs. 70.0%, P = 0.051). No significant differences were observed in the propensity score-matched analysis. Conclusion: Lumbar drainage before endovascular treatment for ruptured intracranial aneurysms is a safe procedure that does not increase the incidence of rebleeding.

Image Quality and Radiation Dose of Conventional and Wide-Field High-Resolution Cone-Beam Computed Tomography for Cerebral Angiography: A Phantom Study.

There has been an increase in the use of interventional neuroradiology procedures because of their non-invasiveness compared to surgeries and the improved image quality of fluoroscopy, digital subtraction angiography, and rotational angiography. Although cone-beam computed tomography (CBCT) images are inferior to multi-detector CT images in terms of low-contrast detectability and lower radiation doses, CBCT scans are frequently performed because of their accessibility. This study aimed to evaluate the image quality and radiation dose of two different high-resolution CBCTs (HR CBCT): conventional (C-HR CBCT) and wide-field HR CBCT (W-HR CBCT). The modulation transfer function (MTF), noise power spectrum (NPS), and contrast-to-noise ratio (CNR) were used to evaluate the image quality. On comparing the MTF of C-HR CBCT with a 256 × 256 matrix and that of W-HR CBCT with a 384 × 384 matrix, the MTF of W-HR CBCT with the 384 × 384 matrix was larger. A comparison of the NPS and CNR of C-HR CBCT with a 256 × 256 matrix and W-HR CBCT with a 384 × 384 matrix showed that both values were comparable. The reference air kerma values were equal for C-HR CBCT and W-HR CBCT; however, the value of the kerma area product was 1.44 times higher for W-HR CBCT compared to C-HR CBCT. The W-HR CBCT allowed for improved spatial resolution while maintaining the image noise and low-contrast detectability by changing the number of image matrices from 256 × 256 to 384 × 384. Our study revealed the image characteristics and radiation dose of W-HR CBCT. Given its advantages of low-contrast detectability and wide-area imaging with high spatial resolution, W-HR CBCT may be useful in interventional neuroradiology for acute ischemic stroke.

Safety and efficacy of transgraft internal trapping after proximal internal carotid artery ligation with high-flow bypass.

OBJECTIVE: Proximal internal carotid artery (ICA) ligation with high-flow bypass is an important vascular reconstructive technique for giant ICA aneurysms or skull base tumors involving the ICA to control intraoperative bleeding. Retrograde or collateral blood flow occasionally remains postoperatively and requires complete internal trapping. Although transgraft internal trapping is one of the options, there are few reports on transgraft treatment. The purpose of this study was to report our experience of transgraft internal trapping and evaluate the safety and efficacy of this procedure. METHODS: We retrospectively selected patients who underwent transgraft internal trapping after proximal ICA ligation with high-flow bypass between January 2012 and June 2020. RESULTS: We encountered five cases of this procedure (one aneurysm case and four tumor cases). The median duration between the bypass and transgraft internal trapping was 12 days. In four out of five cases, a guiding catheter could be placed in the graft. No disruption of the anastomosis was observed. Transgraft internal trapping was achieved in all five cases with detachable coils. All treatments could be completed safely without any adverse events, including ischemic and hemorrhagic complications. CONCLUSIONS: Transgraft internal trapping after proximal ICA ligation with high-flow bypass may be an option for preventing residual retrograde blood flow.

Aneurysm Isolation is Associated with Complete Occlusion of Aneurysms After Flow Diverter Treatment.

PURPOSE: Some aneurysms remain patent after treatment with flow diverters (FD) due to residual blood flow in the aneurysm. Several studies have proposed that branches and residual flow are associated with delayed aneurysm occlusion. We propose that aneurysm isolation (i.e., the complete disconnection of the aneurysm from surrounding vessels) might be a possible factor facilitating aneurysm occlusion. This study aimed to determine if aneurysm isolation was a factor associated with aneurysm occlusion after FD treatment. METHODS: We reviewed 80 internal carotid artery (ICA) aneurysms treated with FDs between October 2014 and April 2021. Aneurysm isolation was assessed in high-resolution cone-beam computed tomograms at the end of each treatment. Aneurysms with incorporated branches and those with connections to other branches due to stent malapposition were deemed to be nonisolated. Other factors, such as patient age, sex, anticoagulant use, aneurysm size, adjunct coil use, and the presence of incorporated branches, were considered. The degree of aneurysm occlusion (complete or incomplete) was assessed by follow-up angiograms 12 months after treatment. RESULTS: Complete occlusion was achieved in 57 of 80 aneurysms (71%). Completely occluded aneurysms had a significantly higher ratio of isolation compared to incompletely occluded aneurysms (91.2% vs. 69.6%, P = 0.032). Multivariate logistic regression analysis showed that aneurysm isolation was the sole significant predictor of complete aneurysm occlusion (odds ratio, OR 19.38; 95% confidence interval, CI 2.280-164.657; P = 0.007). CONCLUSION: Aneurysm isolation is a significant factor contributing to complete occlusion after FD treatment.