A Phantom Menace to Medical Personnel During Endovascular Treatment of Cerebral Aneurysms: Real-Time Measurement of Radiation Exposure During Procedures

BACKGROUND

The number of endovascular treatment procedures performed for cerebral aneurysms has markedly increased. However, little is known about the annual effective radiation dose to medical staff in neurointervention fields. We performed a retrospective observational study to investigate the real-time radiation dose to surgeons, nurses, anesthesiologists, and radiologic technologists during endovascular treatment of intracranial aneurysms.

METHODS

We measured the real-time radiation doses for 2 weeks using standard and reinforced protection, during which 28 procedures were performed, including 23 coil embolizations for unruptured intracranial aneurysms. Four procedures were excluded because of an inadequately equipped sensor, which resulted in inappropriate data collection. The procedure time was defined from intubation to extubation. Five RaySafe i2 detectors were installed at the chest level of the operator, attending nurse, radiologic technologist, and anesthesiologist and just inside the front door of the hybrid operating room.

RESULTS

The median doses per session with standard protection to the operator, attending nurse, anesthesiologist, and radiologic technologist were 11.16, 2.60, 4.76, and 1.93 μSv, respectively. The dose to the operator, attending nurse, and anesthesiologist had decreased to 6.63, 0.39, and 1.52 μSv under reinforced protection, respectively. However, the session dose for the radiologic technologist had increased to 3.12 μSv.

CONCLUSIONS

We confirmed the differences in the amount of radiation exposure for different roles. An additional lead screen, which provided more effective protection on the operator side, was proved effective for attenuating radiation exposure during endovascular treatment. All personnel involved in the hybrid operating room were exposed to acceptable effective doses.

The Relationship between Blood Pressure Variability, Recanalization Degree, and Clinical Outcome in Large Vessel Occlusive Stroke after an Intra-Arterial Thrombectomy

BACKGROUND

Blood pressure variability (BPV) is associated with target organ damage progression and increased cardiovascular events, including stroke. The aim of this study was to evaluate the associations between short-term BPV during acute periods and recanalization degree, early neurological deterioration (END) occurrence, and functional outcomes in acute ischemic stroke patients who had undergone intra-arterial thrombectomy (IAT).

METHODS

We retrospectively analyzed 303 patients with large vessel occlusive stroke who underwent IAT. The following BPV parameters, measured over 24 and 48 h after IAT, were compared: the mean, SD, coefficient of variation (CV), variation independent of the mean (VIM) for both the systolic BP (SBP) and diastolic BP, and the proportion of nocturnal SBP risers.

RESULTS

BPV parameters decreased with higher recanalization degree. The mean SBP (SBPmean) over 24 and 48 h after IAT, and the SD of SBP (SBPSD), CV of SBP (SBPCV), and VIM of SBP (SBPVIM) during the 48 h following the procedure had significant associations with recanalization degree. Patients with END had higher BPV than that of those without END, and the difference was more evident for incomplete recanalization. Increased BPV was associated with a shift toward poor functional outcome at 3 months after adjustment, including recanalization degree (OR range for significant parameters, 1.26-1.64, p = 0.006 for 48 h SBPmean, p = 0.003 for 48 h SBPCV, otherwise p < 0.002).

CONCLUSIONS

Short-term BPV over 24 and 48 h after IAT in acute ischemic stroke patients was related to recanalization degree, and END occurrence, and may be an independent predictor of clinical outcome.

Machine learning for detecting moyamoya disease in plain skull radiography using a convolutional neural network

Background

Recently, innovative attempts have been made to identify moyamoya disease (MMD) by focusing on the morphological differences in the head of MMD patients. Following the recent revolution in the development of deep learning (DL) algorithms, we designed this study to determine whether DL can distinguish MMD in plain skull radiograph images.

Methods

Three hundred forty-five skull images were collected as an MMD-labeled dataset from patients aged 18 to 50 years with definite MMD. As a control-labeled data set, 408 skull images of trauma patients were selected by age and sex matching. Skull images were partitioned into training and test datasets at a 7:3 ratio using permutation. A total of six convolution layers were designed and trained. The accuracy and area under the receiver operating characteristic (AUROC) curve were evaluated as classifier performance. To identify areas of attention, gradient-weighted class activation mapping was applied. External validation was performed with a new dataset from another hospital.

Findings

For the institutional test set, the classifier predicted the true label with 84·1% accuracy. Sensitivity and specificity were both 0·84. AUROC was 0·91. MMD was predicted by attention to the lower face in most cases. Overall accuracy for external validation data set was 75·9%.

Interpretation

DL can distinguish MMD cases within specific ages from controls in plain skull radiograph images with considerable accuracy and AUROC. The viscerocranium may play a role in MMD-related skull features.

Fund

This work was supported by grant no. 18-2018-029 from the Seoul National University Bundang Hospital Research Fund.

Pathogenesis of dorsal internal carotid artery wall aneurysms based on histopathologic examination and microscopic configuration

Blood blister-like aneurysms (BBAs) are an important cause of subarachnoid hemorrhage (SAH), but proper treatment is uncertain due to the poor prognosis of these aneurysms. The pathogenesis of BBAs remains unclear and few studies have reported on histological examinations of BBAs because it is difficult to obtain a specimen due to a high risk of intraoperative bleeding. In this report, BBAs were histopathologically examined in two patients who presented with SAH due to rupture of a BBA that was treated with surgical trapping and bypass surgery. BBA specimens including the adjacent internal carotid artery (ICA) walls were obtained intraoperatively. We suggest the pathogenesis of BBAs based on histopathologic examination and microscopic configuration.

Epidemiology of ruptured brain arteriovenous malformation: a National Cohort Study in Korea

OBJECTIVE

Brain arteriovenous malformation (BAVM) is a rare cerebrovascular disease that causes intracranial hemorrhage. Although several reports have demonstrated the epidemiological features of BAVM in Western countries, no epidemiological investigations regarding BAVM have been reported in Korea. The authors aimed to investigate the national epidemiology of ruptured BAVM in a Korean population.

METHODS

The authors used data from the National Health Insurance Service-National Sample Cohort (NHIS-NSC). The original cohort included approximately 1 million individuals (2% of the Korean population) with 12-year claim data (2002-2013). To construct an initial cohort for investigation, the authors selected 1,016,820 registered individuals in 2005. Subjects with a history of cerebrovascular disease (code I6xx) and BAVM (Q282) between 2002 and 2004 were washed-out to identify incident cases. During the 9-year follow-up (2005-2013), the incidence of BAVM was calculated using the earliest date of diagnosis of ruptured or unruptured BAVM. Direct standardization was applied to the crude incidence. Mortality and disability were evaluated using registration data. Related diagnostic procedures were also analyzed.

RESULTS

A total of 8,802,696 person-years of observation were noted. During observation, 308 patients were diagnosed with a ruptured BAVM. The crude incidence of ruptured BAVM was 3.5 per 100,000 person-years. There was no sex difference in incidence. The mortality rate for patients with a ruptured BAVM 1 month after diagnosis was 12.7%. At 1-year and 5-year follow-up examinations, mortality rates were 17.2% and 22.1%, respectively. Severe disability-free survival rates of patients with ruptured AVMs were 75.3% and 69.8% at 1-year and 5-year follow-up, respectively.

CONCLUSIONS

The standardized incidence of ruptured BAVMs was 3.6 per 100,000 person-years in Korea. Ruptured BAVMs resulted in high mortality and disability rates.

Long-term outcomes of treatment for unruptured intracranial aneurysms in South Korea: clipping versus coiling

Background

The long-term outcomes of endovascular coiling and surgical clipping for the treatment of unruptured intracranial aneurysms are unclear.

Methods

We performed a nationwide retrospective cohort study using claims data from the Korean Health Insurance Review and Assessment Service on patients undergoing surgical clipping or endovascular coiling from 2008 to 2014. Inverse probability treatment weighting for average treatment effect on the treated and the multiple imputation method were used to balance covariates and handle missing values. The primary outcome was all-cause mortality at 7 years.

Results

We identified 26 411 patients of whom 11 777 underwent surgical clipping and 14 634 underwent endovascular coiling. After adjustment with the use of inverse probability treatment weighting for average treatment effect on the treated, all-cause mortality rates at 7 years were 3.8% in the endovascular coiling group and 3.6% in the surgical clipping group (HR 1.05; 95% CI 0.86 to 1.28; P=0.60, log-rank test). The adjusted probabilities of aneurysm rupture at 7 years were 0.9% after endovascular coiling and 0.7% after surgical clipping (HR 0.9; 95% CI 0.61 to 1.34; P=0.63, log-rank test). The probabilities of retreatment at 7 years after adjustment were 4.9% in the endovascular coiling group and 3.2% in the surgical clipping group (HR 1.52; 95% CI 1.28 to 1.81; P<0.001, log-rank test).

Conclusions

All-cause mortality at 7 years was similar between the elective surgical clipping and endovascular coiling groups in patients with unruptured aneurysms who had no history of subarachnoid hemorrhage due to aneurysm rupture.

Surgical Treatment of Adult Moyamoya Disease

PURPOSE OF REVIEW

Moyamoya disease (MMD) is being increasingly diagnosed with the development of radiological surveillance technology and increased accessibility to medical care. Accordingly, there have been several recent reports on treatment outcomes in MMD. In this review, we summarize recent advances in surgical treatment and outcomes of adult MMD, while addressing related controversies.

RECENT FINDINGS

Recent studies suggest that revascularization surgery leads to significantly more favorable outcomes for stroke prevention, angiographic and hemodynamic changes, and clinical outcomes than does conservative treatment for adult patients with ischemic MMD. Moreover, direct revascularization methods should be considered as the first-line treatment over indirect methods, although the latter may be considered if a direct method is not possible. In cases of hemorrhagic MMD, several studies have demonstrated that surgical treatment is more effective than conservative treatment in preventing further hemorrhage. In addition to revascularization surgery, endovascular treatment is emerging as a breakthrough therapy for hemorrhagic MMD. Accumulating evidence regarding the surgical treatment of adult MMD suggests the benefit of revascularization over conservative management for both ischemic and hemorrhagic patients. However, the benefit of revascularization in asymptomatic adult MMD remains unclear.

Relevance of Antiplatelet Therapy Duration After Stent-Assisted Coil Embolization for Unruptured Intracranial Aneurysms

BACKGROUND

The optimal duration of dual-antiplatelet therapy (DAPT) for preventing delayed thromboembolic events (DTEs) remains unclear. We aimed to determine whether longer DAPT provides improved protection against delayed DTEs.

METHODS

This retrospective cohort study included 507 stent-assisted coil embolization procedures using a single stent for unruptured intracranial aneurysms. We performed coarsened exact matching according to the duration of maintenance DAPT. DTEs were defined as any neurologic symptoms concerning the stented vascular territory and occurring at 1 month or later after the procedure. After stratification according to DAPT duration (short-term, <9 months; long-term, ≥9 months), the log-rank test and Z-analysis were performed to evaluate the efficacy of long-term DAPT for preventing DTEs.

RESULTS

Of 507 treated patients (median follow-up, 44 months), 25 (4.9%) experienced DTEs at 1 month after the procedure. Among all DTEs, 9 (1.8%) were infarctions confirmed on magnetic resonance imaging. Permanent neurologic deficit (modified Rankin Scale score ≥2) occurred in 2 (0.4%) patients. On procedure-to-event analysis, long-term DAPT was not superior for preventing DTEs. Most events occurred within 1 month of switching from DAPT to single-antiplatelet therapy, regardless of DAPT duration. The longest time from the procedure to DTE occurrence was 22 months. Age older than 54.5 years was identified as independent risk factor for DTE-stroke.

CONCLUSIONS

Compared with short-term DAPT, long-term DAPT delays the occurrence of DTEs but does not lower their incidence. Longer-term DAPT (>9 months) should be considered after stent-assisted coil embolization for unruptured intracranial aneurysms, although its efficacy remains to be clarified.

Nationwide Mortality Data after Flow-Diverting Stent Implantation in Korea

Objective

To investigate nationwide statistics on flow-diverting stent usage for cerebral aneurysm treatment and related mortality data.

Methods

We requested data extraction from the National Health Insurance Service claims database using electronic data interchange codes (J3207064, J3207073). Patient and hospital information as well as death statistics were collected from the database.

Results

A total of 169 procedures were performed using flow-diverting stents for cerebral aneurysm treatment from November 2014 to December 2016 in Korea. The majority of primary diagnosis was unruptured intracranial aneurysm. During the study period, nine subjects died, including one patient initially diagnosed with subarachnoid hemorrhage. The crude mortality rate was 5.3%. Five patients died within one month after the procedure; therefore, the estimated periprocedural mortality rate was 3.0±1.3%. The mortality rate as of the last day of 2016 was 6.3±2.1%.

Conclusion

In a 171 person-year follow-up in a Korean series, nine deaths occurred after flow-diverting stent treatment. The crude mortality rate in Korea (5.3%) was higher than that reported in a previous meta-analysis (3.8%).

Endovascular Treatment of Bilateral Cavernous Sinus Dural Arteriovenous Fistula: Therapeutic Strategy and Follow-Up Outcomes

Objective

Bilateral cavernous sinus dural arteriovenous fistula (CSdAVF) is very rare, even in Asian countries. The research intended to present clinical and radiologic outcomes of treating such fistulas through endovascular embolization.

Materials and Methods

Data was obtained from 220 consecutive patients, with CSdAVF, who were treated from January 2004 to December 2015. Bilateral CSdAVF was identified in 17 patients (7.7%). The clinical and radiologic outcomes of the fistulas were assessed with an emphasis on the technical aspects of treatment.

Results

At the time of treatment, 7 and 10 patients presented with bilateral and unilateral symptoms, respectively. In the former cases, 4 patients had progressed from unilateral to bilateral symptoms. Bilateral fistulas were treated with a single-stage transvenous embolization (TVE) in 15 patients, via bilateral inferior petrosal sinuses (IPS) (n = 9) and unilateral IPS (n = 6). In the other 2 patients with one-sided dominance of shunting, only dominant fistula was treated. Two untreated lesions were found on follow-up to have spontaneously resolved after treatment of the dominant contralateral fistula. Of the 34 CSdAVF lesions, complete occlusion was achieved in 32 lesions after TVE. Seven patients (41.2%) developed worsening of cranial nerve palsy after TVE. During the follow-up period, 4 patients obtained complete recovery, whereas the other 3 remained with deficits.

Conclusion

With adjustments of endovascular procedures to accommodate distinct anatomical configurations, endovascular treatment for bilateral CSdAVF can achieve excellent angiographic occlusion results. However, aggravation of symptoms after TVE may occur frequently in bilateral CSdAVF. In the patients with one-sided dominance of shunt, treatment of only dominant fistula might be an alternative option.

Radiologic Measurement of Brain Swelling in Patients with Large Hemispheric Infarctions During Targeted Temperature Management

Brain herniation is most often the result of severe brain swelling and can rapidly lead to death or brain death. We retrospectively identified radiologic indicators to evaluate the effects of targeted temperature management (TTM) on the extent of cerebral edema and determine the cutoff values that best predict TTM outcomes in patients with large hemispheric infarction. We retrospectively reviewed brain computed tomography (CT) scans of 21 patients with large hemispheric infarctions, who were treated with TTM. We excluded 4 patients whose CT scans were inadequate for evaluation, which left 17 patients. We divided the patients into success and failure groups. TTM failure was defined as death or the need for decompressive hemicraniectomy (DHC) after TTM. Infarction size was measured as the total restricted area in diffusion-weighted imaging that was performed on admission. CT scans were obtained on the first and second days after TTM initiation and then every 2 days. We measured septum pellucidum shifts (SPS) and pineal gland shifts (PGS) on CT scans. The median time from symptom onset to TTM initiation was 14.5 hours. Ten patients were successfully treated with TTM, six patients died, and one patient underwent a DHC. Initial infarction sizes were not significantly different between the success and failure groups (p = 0.529), but the SPS and PGS at 36-72 hours after TTM initiation were (mean SPS: 5.0 vs. 14.9 mm, p = 0.001; mean PGS: 2.3 vs. 7.9 mm, p = 0.001). The sensitivity and negative predictive value for TTM failure caused by cerebral edema (SPS ≥9.25 mm and PGS ≥3.70 mm) at 36-72 hours after TTM initiation were both 100%. The SPS and PGS on CT scans taken 36-72 hours after TTM initiation may help to estimate the effect of TTM on cerebral edema and guide further treatment.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma

Purpose To evaluate the effect of middle meningeal artery (MMA) embolization on chronic subdural hematoma (CSDH) and compare the treatment outcomes of MMA embolization and conventional treatment. Materials and Methods All consecutive patients 20 years or older with CSDH were assessed for eligibility. CSDHs with a focal location, a thickness of 10 mm or less, no mass effect, or underlying conditions were excluded. Seventy-two prospectively enrolled patients with CSDH underwent MMA embolization (embolization group; as the sole treatment in 27 [37.5%] asymptomatic patients and with additional hematoma removal for symptom relief in 45 [62.5%] symptomatic patients). For comparison, 469 patients who underwent conventional treatment were included as a historical control group (conventional treatment group; close, nonsurgical follow-up in 67 [14.3%] and hematoma removal in 402 [85.7%] patients). Primary outcome was treatment failure defined as a composite of incomplete hematoma resolution (remaining or reaccumulated hematoma with thickness > 10 mm) or surgical rescue (hematoma removal for relief of symptoms that developed with continuous growth of initial or reaccumulated hematoma). Secondary outcomes included surgical rescue as a component of the primary outcome and treatment-related complication for safety measure. Six-month outcomes were compared between the study groups with logistic regression analysis. Results Spontaneous hematoma resolution was achieved in all of 27 asymptomatic patients undergoing embolization without direct hematoma removal. Hematoma reaccumulation occurred in one (2.2%) of 45 symptomatic patients receiving embolization with additional hematoma removal. Treatment failure rate in the embolization group was lower than in the conventional treatment group (one of 72 patients [1.4%] vs 129 of 469 patients [27.5%], respectively; adjusted odds ratio [OR], 0.056; 95% confidence interval [CI]: 0.011, 0.286; P = .001). Surgical rescue was less frequent in the embolization group (one of 72 patients [1.4%] vs 88 of 469 patients [18.8%]; adjusted OR, 0.094; 95% CI: 0.018, 0.488; P = .005). Treatment-related complication rate was not different between the two groups (0 of 72 patients vs 20 of 469 patients [4.3%]; adjusted OR, 0.145; 95% CI: 0.009, 2.469; P = .182). Conclusion MMA embolization has a positive therapeutic effect on CSDH and is more effective than conventional treatment. ^© RSNA, 2017.

Surgical Removal of a Ruptured Radiculomedullary Artery Aneurysm: A Case Report

Subarachnoid hemorrhage due to a solitary spinal aneurysm is extremely rare, and diagnosis and treatment are challenging. We report a rare case of a ruptured radiculomedullary artery aneurysm in a patient with Behçet disease. A 49-year-old man presented with severe lower abdominal and leg pain. Magnetic resonance imaging was performed and an enhanced intradural-extramedullary lesion at the T12 spinal level with subarachnoid hemorrhage was identified. Diagnostic spinal angiography was performed to evaluate the vascular lesion, and a radiculomedullary artery aneurysm at the T12 level was identified. We performed surgical resection of the aneurysm and a good neurological outcome was obtained.

Dose-Dependent Effect of Statin Pretreatment on Preventing the Periprocedural Complications of Carotid Artery Stenting

BACKGROUND AND PURPOSE

We investigated whether statin pretreatment can dose dependently reduce periprocedural complications in patients undergoing carotid artery stenting because of symptomatic carotid artery stenosis.

METHODS

We enrolled a consecutive series of 397 symptomatic carotid artery stenosis (≥50% stenosis on conventional angiography) treated with carotid artery stenting at 2 tertiary university hospitals over a decade. Definition of periprocedural complications included any stroke, myocardial infarction, and death within 1 month after or during the procedure. Statin pretreatment was divided into 3 categories according to the atorvastatin equivalent dose: none (n=158; 39.8%), standard dose (<40 mg of atorvastatin, n=155; 39.0%), and high dose (≥40 mg; n=84; 21.2%). A multivariable logistic regression analysis with the generalized estimating equation method was used to investigate independent factors in periprocedural complications.

RESULTS

The patients' mean age was 68.7 years (81.6% men). The periprocedural complication rates across the 3 categories of statin use were 12.0%, 4.5%, and 1.2%. After adjustment, a change in the atorvastatin dose category was associated with reduction in the odds of periprocedural complications for each change in dose category (standard-dose statin: odds ratio, 0.24; 95% confidence interval, 0.07-0.81; high-dose statin: odds ratio, 0.11; 95% confidence interval, 0.01-0.96; P for trend=0.01). Administration of antiplatelet drugs was also an independent factor in periprocedural complications (OR, 0.18; 95% CI, 0.05-0.69).

CONCLUSIONS

This study shows that statin pretreatment may reduce the incidence of periprocedural complications dose dependently in patients with symptomatic carotid artery stenting.

Bypass Surgery for Complex Intracranial Aneurysms: 15 Years of Experience at a Single Institution and Review of Pertinent Literature

BACKGROUND

Bypass surgery is a treatment option for complex intracranial aneurysms.

OBJECTIVE

To determine the utility of bypass surgery for the treatment of complex intracranial aneurysms and to review the literature on this topic.

METHODS

Sixty-two patients were included in this retrospective study. Unruptured aneurysms were dominant (80.6%), and the internal carotid artery was the most common location of the aneurysm (56.4%), followed by the middle cerebral artery (21.0%). The mean maximal diameter of the aneurysms was 20.5 ± 11.4 mm. The clinical and angiographic states were evaluated preoperatively, immediately after surgery (within 3 days) and at the last follow-up. The mean angiographic and clinical follow-up duration was 34.2 ± 38.9 and 46.5 ± 42.5 months, respectively.

RESULTS

Sixty-one patients (98.3%) underwent extracranial–intracranial bypass, and 1 underwent intracranial–intracranial bypass. At the last follow-up angiography, 58 aneurysms (93.5%) were completely obliterated and 4 were incompletely obliterated, with a graft patency of 90.3%. Surgical mortality was 0 and permanent morbidity was 8.1%. A good clinical outcome (Karnofsky Performance Scale ≥ 70 and modified Rankin Scale score ≤ 2) was achieved in 91.9% of patients (n = 57).

CONCLUSION

With a proper selection of bypass type, bypass-associated treatment can be a good alternative for patients with complex intracranial aneurysms when conventional microsurgical clipping or endovascular intervention is not feasible.

Reversible cerebral vasoconstriction syndrome combined with posterior reversible encephalopathy syndrome after heart transplantation

Reversible cerebral vasoconstriction syndrome (RCVS) combined with posterior reversible encephalopathy syndrome (PRES) is a rare complication in patients treated with immunosuppressants. A 52-year-old male patient presented with seizures after heart transplantation. The patient was suspected of having PRES on brain images. Despite the strict blood pressure control, the patient presented with altered mentality and the brain images showed a newly developed large acute infarction. Digital subtraction angiography (DSA) revealed the classic "sausage on a string" appearance of the cerebral arteries - potential feature of RCVS. To our knowledge, this is the first case report to describe RCVS combined with PRES after heart transplantation.

Educational and interactive informed consent process for treatment of unruptured intracranial aneurysms

OBJECTIVE

For patients with unruptured intracranial aneurysms (UIAs), the information transfer that precedes informed consent needs to be in-depth and detailed, as most patients with a UIA have no symptoms, yet the risks related to treatment are relatively high. Thus, in this study an educational and interactive program was proposed for patients with UIAs to improve the informed consent process and assess the level of comprehension.

METHODS

A total of 110 patients with UIAs underwent the proposed educational and interactive informed consent (EIIC) process and were enrolled in this study. The EIIC process combines patient education using information booklets, a cartoon book, a video, an initial physician-patient interview, answering a questionnaire, a second physician-patient interview based on the questionnaire results, and finally consent. After the first physician-patient interview that provides the patient with specific information, including his or her angiographic characteristics, medical condition, and recommended treatment, the patient is requested to answer a questionnaire composed of 3 parts: demographic information, including the patient's age, sex, and years of education; 13 medical questions to assess the patient's knowledge about his or her UIA; and an evaluation of the usefulness of the educational resources. The control group consisted of 65 patients from 3 other tertiary university hospitals where the EIIC process was not used.

RESULTS

The questionnaire scores of the EIIC group ranged from 7 to 13 (mean ± SD: 11.9 ± 1.3) and were significantly higher than those for the controls (10.2 ± 1.9, p < 0.001). The better comprehension of the patients in the EIIC group was remarkable as they were significantly older than those in the control group (62.7 ± 8.3 years vs 55.9 ± 10.5 years, respectively; p < 0.001). For both the EIIC group and the control group, a Pearson correlation analysis revealed a positive correlation (r = 0.232 for the EIIC group, r = 0.603 for controls) between the years of education and the questionnaire score (p = 0.015 for the EIIC group, p < 0.001 for the controls), whereas no correlation was found between the patient age and the questionnaire score. For the EIIC group, the verbal information from the attending physician was selected by 90 patients (81.8%) as the most useful and informative educational method, while the most effective reinforcement of this verbal communication was the video (n = 86; 78.2%), information booklets (n = 16; 14.5%), the Internet (n = 7; 6.4%), and the cartoon book (n = 1; 0.9%).

CONCLUSIONS

The proposed standardized EIIC process resulted in good patient comprehension about UIAs. The verbal information from the attending physician was the most informative, and the video was the most effective reinforcement of the verbal communication. The patient level of comprehension was shown to be correlated with years of education.

Y-configuration Stent-assisted Coil Embolization for Wide-necked Intracranial Bifurcation Aneurysms

OBJECTIVE

The objective of this study was to determine the efficiency and safety of Y configuration stent-assisted coiling with double-closed stents for wide-necked intracranial aneurysms located at arterial bifurcations thorough analysis of a multicenter case series.

MATERIALS AND METHODS

A retrospective chart review was done on 10 patients who underwent endovascular treatment of wide-necked intracranial aneurysms with Y-configuration stent-assisted coil embolization in three centers from August 2011 to March 2014. The degree of aneurysmal occlusion was assessed using the Raymond scale. Clinical outcomes were assessed before operation, at discharge, and at the last follow-up visit using the Glasgow outcome scale.

RESULTS

The 10 patients included 6 females and 4 males with a mean age of 58.6 years. Indications for treatment included 6 unruptured intracranial aneurysms and 4 ruptured intracranial aneurysms. Five aneurysms were located at the basilar artery bifurcation, four aneurysms were located in an anterior communicating artery, and one aneurysm was in the pericallosal artery. The mean size of the 10 aneurysms was 9.7 mm. All aneurysms had a dome-to-neck ratio of < 1.5 (mean, 0.89). Immediate complications included one thromboembolic event out of the 10 cases. Immediate posttreatment angiograms showed complete occlusion in 1 aneurysm and residual necks in 9 aneurysms. Follow-up results showed 8 complete occlusions and 2 residual necks. No delayed complications were observed during the follow-up period (mean: 20 months).

CONCLUSION

Y configuration using double-closed cell stents is feasible and safe in selected patients. This method is an acceptable option for managing complex wide-necked bifurcations.

Hemodynamic Changes after Unilateral Revascularization for Moyamoya Disease: Serial Assessment by Quantitative Magnetic Resonance Angiography

BACKGROUND: Ultrasonic flow meters and quantitative magnetic resonance angiography quantitatively assess flow during hemodynamic evaluation of cerebral ischemia. Although their reliability and reproducibility have been verified, their clinical impact in moyamoya disease has rarely been reported.

OBJECTIVE: To investigate flow measurement outcomes in moyamoya disease patients pre- and postoperatively through a retrospective observational study.

METHODS: We evaluated 41 patients undergoing their first revascularization surgery who were followed ≥6 mo. Hemodynamic parameters were recorded preoperatively, at 1 and 6 mo postoperatively, and at the last follow-up. Demographic factors, Suzuki stage, and stroke development were also analyzed.

RESULTS: Patients’ median age was 37 yr (interquartile range [IQR], 27-43), and 16 (39.0%) patients were men. During follow-up, 9 (22.0%) patients experienced postoperative stroke (4 major strokes). Hemodynamic status was improved in 34 (82.9%) patients at the 6-mo follow-up. Median intraoperative flow was 41 mL/min (IQR, 25-59). Bypass flow peaked at 6 mo (median, 67 mL/min; IQR, 35-99). At the 1- and 6-mo follow-ups, ipsilateral hemispheric flow was significantly increased. The median proportion of posterior circulation at 6 mo was 44.4%, significantly lower than the preoperative proportion (50.1%). Abundant intraoperative bypass flow was associated with hemodynamic improvement, while low contralateral hemispheric flow was related with immediate postoperative ischemic stroke.

CONCLUSION: Ipsilateral hemispheric flow was increased during 6-mo follow-up, and posterior circulation flow burden was diminished. Abundant intraoperative bypass flow was associated with postoperative hemodynamic improvement. Low preoperative contralateral hemispheric flow was related with immediate postoperative ischemic stroke.