Influence of circle of Willis modeling on hemodynamic parameters in anterior communicating artery aneurysms and recommendations for model selection.

Computational fluid dynamics (CFD) has been utilized to calculate hemodynamic parameters in anterior communicating artery aneurysm (AComA), which is located at a junction between left and right A1 and A2 segments. However, complete or half circle of Willis (CoW) models are used indiscriminately. This study aims to suggest recommendations for determining suitable CoW model. Five patient-specific CoW models with AComA were used, and each model was divided into complete, left-half, and right-half models. After validating the CFD using a flow experiment, the hemodynamic parameters and flow patterns in five AComAs were compared. In four out of five cases, inflow from one A1 side had a dominant influence on the AComA, while both left and right A1 sides affected the AComA in the remaining case. Also, the average difference in time-averaged wall shear stress between the complete and half models for four cases was 4.6%, but it was 62% in the other case. The differences in the vascular resistances of left and right A1 and A2 segments greatly influenced the flow patterns in the AComA. These results may help to enhance clinicians' understanding of blood flow in the brain, leading to improvements in diagnosis and treatment of cerebral aneurysms.

Safety and efficacy of the novel Alpha stent for the treatment of intracranial wide-necked aneurysm.

The Alpha stent is an intracranial closed-cell stent with a unique mesh design to enhance wall apposition. It recently underwent structural modifications to facilitate easier stent deployment. This study aimed to evaluate the safety and efficacy of stent-assisted coil embolization for unruptured intracranial aneurysms using the Alpha stent. Between January 2021 and November 2021, 35 adult patients with 35 unruptured intracranial aneurysms in the distal internal carotid artery were prospectively enrolled. For efficacy outcomes, magnetic resonance angiography at the 6-month follow-up was evaluated using the Raymond-Roy occlusion classification (RROC). The safety outcome evaluated the occurrence of symptomatic procedure-related neurological complications up to 6 months postoperatively. Technical success was achieved in 34/35 (97.1%). Six months postoperatively, aneurysm occlusion showed RROC I in 32/35 (91.4%) and RROC II in 3/35 (8.6%) patients. Procedure-related neurologic complications occurred in one patient (2.9%) who experienced hemiparesis due to acute lacunar infarction, which resulted in a 6-month mRS score of 1. The Alpha stent demonstrated excellent efficacy and safety outcomes in stent-assisted coil embolization of unruptured distal ICA aneurysms. The recent structural modifications allowed for easier stent delivery and deployment.Clinical trial registration number: KCT0005841; registration date: 28/01/2021.

Eye movement analysis for real-world settings using segmented linear regression.

Eye movement analysis is critical to studying human brain phenomena such as perception, cognition, and behavior. However, under uncontrolled real-world settings, the recorded gaze coordinates (commonly used to track eye movements) are typically noisy and make it difficult to track change in the state of each phenomenon precisely, primarily because the expected change is usually a slower transient process. This paper proposes an approach, Improved Naive Segmented linear regression (INSLR), which approximates the gaze coordinates with a piecewise linear function (PLF) referred to as a hypothesis. INSLR improves the existing NSLR approach by employing a hypotheses clustering algorithm, which redefines the final hypothesis estimation in two steps: (1) At each time-stamp, measure the likelihood of each hypothesis in the candidate list of hypotheses by using the least square fit score and its distance from the k-means of the hypotheses in the list. (2) Filter hypothesis based on a pre-defined threshold. We demonstrate the significance of the INSLR method in addressing the challenges of uncontrolled real-world settings such as gaze denoising and minimizing gaze prediction errors from cost-effective devices like webcams. Experiment results show INSLR consistently outperforms the baseline NSLR in denoising noisy signals from three eye movement datasets and minimizes the error in gaze prediction from a low precision device for 71.1% samples. Furthermore, this improvement in denoising quality is further validated by the improved accuracy of the oculomotor event classifier called NSLR-HMM and enhanced sensitivity in detecting variations in attention induced by distractor during online lecture.

Perioperative Low-Dose Aspirin Management for Planned Clipping Surgery: When, How Long, and With What Precautions?

BACKGROUND AND OBJECTIVE: Perioperative low-dose aspirin (ASA) management for open craniotomy surgery lacked information. We analyze to establish the perioperative ASA strategy to minimize both hemorrhagic and thromboembolic complications. METHODS: The investigators designed a multicenter retrospective study, which included patients scheduled to have clipping surgery for unruptured intracranial aneurysm. The incidence and risk factors were analyzed for postoperative hemorrhagic complications and major cardio- and cerebrovascular events (MACCEs) within 1 month postoperation. RESULTS: This study included 503 long-term ASA users of 3654 patients at three tertiary centers. The incidence of hemorrhagic complications and MACCEs was 7.4% (37/503) and 8.8% (44/503), respectively. Older age (>70 years, odds ratio [OR]: 2.928, 95% CI [1.337-6.416]), multiple aneurysms operation (OR: 2.201, 95% CI [1.017-4.765]), large aneurysm (>10 mm, OR: 4.483, 95% CI [1.485-13.533]), and ASA continuation (OR: 2.604, 95% CI [1.222-5.545]) were independent risk factors for postoperative hemorrhagic complications. Intracranial hemorrhage was the only type of hemorrhagic complication that increased in the ASA continuation group (10.6% vs 2.9%, P = .001). Between the ASA continuation and discontinuation groups, the overall incidence of MACCEs was not significantly different (log-rank P = .8). In the subgroup analysis, ASA discontinuation significantly increased the risk of MACCEs in the secondary prevention group (adjusted hazard ratio: 2.580, 95% CI [1.015-6.580]). CONCLUSION: ASA continuation increased the risk of postoperative intracranial hemorrhage. Simultaneously, ASA discontinuation was the major risk factor for postoperative MACCEs in the high-risk group. Without evidence of intracranial hemorrhage, early ASA resumption was indicated (a total cessation duration <7-10 days) in the secondary prevention group.

Investigation of paraclinoid aneurysm formation by comparing the combined influence of hemodynamic parameters between aneurysmal and non-aneurysmal arteries.

Numerous studies have evaluated the effects of hemodynamic parameters on aneurysm formation. However, the reasons why aneurysms do not initiate in intracranial arteries are still unclear. This study aimed to investigate the influence of hemodynamic parameters, wall shear stress (WSS) and strain, on aneurysm formation by comparing between aneurysmal and non-aneurysmal arteries. Fifty-eight patients with paraclinoid aneurysms on one side were enrolled. Based on magnetic resonance angiography, each patient's left and right internal carotid arteries (ICAs) were reconstructed. For a patient having an aneurysm on one side, the ICA with the paraclinoid aneurysm was defined as the aneurysmal artery after eliminating the aneurysm, whereas the opposite ICA without aneurysm was defined as the non-aneurysmal artery. Computational fluid dynamics and fluid-structure interaction analyses were then performed for both aneurysmal and non-aneurysmal arteries. Finally, the relationship between high hemodynamic parameters and aneurysm location was investigated. For aneurysmal arteries, high WSS and strain locations were well-matched with the aneurysm formation site. Also, considerable correlations between high WSS and strain locations were observed. However, there was no significant relationship between high hemodynamic parameters and aneurysm formation for non-aneurysmal arteries. The findings are helpful for understanding aneurysm formation mechanism and encouraging further relevant research.

One-year clinical and radiologic outcomes of Surpass Evolve flow diverter for large unruptured intracranial aneurysms.

BACKGROUND: Surpass Evolve Flow Diverter (SE-FD; Stryker Neurovascular, Kalamazoo, MI, USA) was launched in 2019 as a new generation FD of Surpass Streamline. The aim of this study was to report the effectiveness and safety of SE-FD insertion for unruptured intracranial aneurysm at one-year follow-up. METHODS: Between November 2019 and October 2021, a total of 106 patients with 108 aneurysms were treated with FD in single institution. Of these, SE-FD insertion was performed in 40 patients with 41 aneurysms. At one-year follow-up, clinical and angiographic outcomes were retrospectively evaluated from electronic medical record and aneurysm database. RESULTS: There were 12 male and 28 female patients (mean age 59.1 years, 95% CI: 55.3-62.9). Fusiform aneurysm dissection was 46.3% (19/41). Mean maximum aneurysm diameter was 13.2 mm (SD 5.53), and 34.1% (14/41) of aneurysms were 15 mm or bigger. Among 41 aneurysms, complex aneurysm (recurred, thrombosed, or branch artery-incorporated) was accounted for 41.5% (17/41). All procedures were successfully conducted with 7.3% (3/41) of procedure-related complications. At one-year follow-up (N.=40), neurologic morbidity was noted in 2 cases (5.0%; both with modified Rankin Scale [mRS] 1) without any mortality. At one-year follow-up (N.=41), radiologic outcomes were adequate occlusion in 33 (80.5%) and complete occlusion in 29 (70.7%). There was no retreatment in our cohort. CONCLUSIONS: Surpass Evolve Flow Diverter seemed to be safe and effective for the treatment of dissecting/fusiform or complex aneurysms at one-year follow-up. However, further study is needed to evaluate long term results.

Surgical outcomes of acetabular fracture of elderly patients with superomedial dome impaction.

This study aimed to investigate the outcomes of elderly acetabular fractures according to the reduction of impacted dome fragments. A retrospective cohort study was performed in two institutions. Fifty-four patients aged ≥ 60 years with acetabular fractures were enrolled. Data for dome impaction and postoperative reduction was collected. Patients were divided into the good reduction group (displacement ≤ 3 mm) and poor reduction group (displacement > 3 mm). Postoperative osteoarthritis (OA), Harris hip score (HHS), total hip arthroplasty conversion, good/poor outcomes were compared between the two groups. The good reduction group (N = 45) demonstrated a lower proportion of radiographic OA (18 vs. 77%, P = 0.001), higher HHS (82.1 vs. 68.6, P = 0.022), and higher proportion of good outcomes than the poor reduction group (N = 9) (89 vs. 22%, P < 0.001). In a subgroup analysis of the patients with dome impaction, the good reduction group had a higher proportion of good outcomes (80 vs. 20%, P = 0.031). On comparing within the good reduction group, dome impaction did not influence clinical outcomes. Elderly acetabular fractures demonstrated favorable outcomes when adequate reduction was achieved even with dome impaction. Well-reduced dome impaction could achieve satisfactory outcomes in elderly acetabular fractures.

Prediction of cerebral hemorrhagic transformation after thrombectomy using a deep learning of dual-energy CT.

OBJECTIVES: To develop and validate a deep learning model for predicting hemorrhagic transformation after endovascular thrombectomy using dual-energy computed tomography (CT). MATERIALS AND METHODS: This was a retrospective study from a prospective registry of acute ischemic stroke. Patients admitted between May 2019 and February 2023 who underwent endovascular thrombectomy for acute anterior circulation occlusions were enrolled. Hemorrhagic transformation was defined using follow-up magnetic resonance imaging or CT. The deep learning model was developed using post-thrombectomy dual-energy CT to predict hemorrhagic transformation within 72 h. Temporal validation was performed with patients who were admitted after July 2022. The deep learning model's performance was compared with a logistic regression model developed from clinical variables using the area under the receiver operating characteristic curve (AUC). RESULTS: Total of 202 patients (mean age 71.4 years ± 14.5 [standard deviation], 92 men) were included, with 109 (54.0%) patients having hemorrhagic transformation. The deep learning model performed consistently well, showing an average AUC of 0.867 (95% confidence interval [CI], 0.815-0.902) upon five-fold cross validation and AUC of 0.911 (95% CI, 0.774-1.000) with the test dataset. The clinical variable model showed an AUC of 0.775 (95% CI, 0.709-0.842) on the training dataset (p < 0.01) and AUC of 0.634 (95% CI, 0.385-0.883) on the test dataset (p = 0.06). CONCLUSION: A deep learning model was developed and validated for prediction of hemorrhagic transformation after endovascular thrombectomy in patients with acute stroke using dual-energy computed tomography. CLINICAL RELEVANCE STATEMENT: This study demonstrates that a convolutional neural network (CNN) can be utilized on dual-energy computed tomography (DECT) for the accurate prediction of hemorrhagic transformation after thrombectomy. The CNN achieves high performance without the need for region of interest drawing. KEY POINTS: • Iodine leakage on dual-energy CT after thrombectomy may be from blood-brain barrier disruption. • A convolutional neural network on post-thrombectomy dual-energy CT enables individualized prediction of hemorrhagic transformation. • Iodine leakage is an important predictor of hemorrhagic transformation following thrombectomy for ischemic stroke.

Neonatal erythema multiforme associated with a rotavirus infection: A case report.

BACKGROUND: Erythema multiforme (EM) is an extremely rare condition in neonates, and studies suggest its association with certain infections and neonatal vaccinations; however, few specific etiological agents have been identified. Rotavirus, a common pathogenic gastrointestinal virus in the neonatal period that is preventable via vaccination, has not been identified as a possible etiology. We report the case of a neonate who was referred for skin lesions presenting as EM, where a meticulous workup identified rotavirus as the sole causative agent. CASE SUMMARY: A 14-day-old male infant was admitted to our hospital with a 1-day history of skin lesions. No medical history or medication intake was recorded. Except for the complaint of skin lesions, the caregivers denied any abnormal symptoms. Multiple tests, including routine laboratory evaluations, were performed to identify the cause of skin lesions. Serological tests for Immunoglobulin M for Toxoplasma, Rubella, Cytomegalovirus, Herpes Simplex Virus, and Epstein-Barr virus viral-capsid antigen were all negative. Multiple polymerase chain reaction (PCR) tests for respiratory viruses and bacterial pathogens were negative (including the severe acute respiratory syndrome coronavirus 2). Multiple PCR tests for gastrointestinal viruses and bacterial pathogens demonstrated evidence of rotavirus infection. No growth was reported in the blood and urine cultures. The patient received intravenous fluids for hydration; meanwhile, no other medications were prescribed. The lesions improved rapidly without specific treatment, and full recovery was achieved within a week. CONCLUSION: The possibility of rotavirus, a major cause of pediatric gastrointestinal infections, being a trigger for neonatal EM should be considered.

Endoscope-assisted microsurgical clipping and reduction of post-clipping cerebral infarction: historical comparison using diffusion-weighted images.

Endoscopic assistance for aneurysm clipping and its possible benefits have been suggested in previous studies, but its clinical significance has not been fully elucidated. This study aimed to present the efficacy of endoscopy-assisted clipping in reducing post-clipping cerebral infarction (PCI) and clinical outcomes via a historical comparison of patients in our institution from January 2020 to March 2022. A total of 348 patients were included, 189 of whom underwent endoscope-assisted clipping. The overall incidence of PCI was 10.9% (n = 38); it was 15.7% (n = 25) before applying endoscopic assistance and decreased to 6.9% (n = 13) after endoscope application (p = 0.010). The application of a temporary clip (odds ratio [OR]: 2.673, 95% confidence interval [CI]: 1.291-5.536), history of hypertension (OR: 2.176, 95% CI: 0.897-5.279), history of diabetes mellitus (OR: 2.530, 95% CI: 1.079-5.932), and current smoker (OR: 3.553, 95% CI: 1.288-9.802) were independent risk factors of PCI, whereas endoscopic assistance was an independent inverse risk factor (OR: 0.387, 95% CI: 0.182-0.823). Compared to the location of the unruptured intracranial aneurysms, internal carotid artery aneurysms showed a significant decrease in the incidence of PCI (5.8% vs. 22.9%, p = 0.019). In terms of clinical outcomes, PCI was a significant risk factor for longer admission duration, intensive care unit stay, and poor clinical outcomes. However, endoscopic assistance itself was not a significant risk factor for clinical outcomes on the 45-day modified Rankin Scale. In this study, we noted the clinical significance of endoscope-assisted clipping in preventing PCI. These findings could reduce the incidence of PCI and improve the understanding of its mechanisms of action. However, a larger and longer-term study is required to evaluate the benefits of endoscopy on clinical outcomes.

Subdural hygroma and hemorrhagic conversion after microsurgical clipping for unruptured intracranial aneurysm.

BACKGROUND: Chronic subdural hematoma (cSDH) is a unique hemorrhagic complication associated with microsurgical clipping. We aimed to investigate the risk factors of subdural hygroma (SDG) formation and its hemorrhagic conversion to cSDH. METHODS: We reviewed the medical records of 229 patients who underwent microsurgical clipping for unruptured intracranial aneurysms (UIA) from 2016 to 2019. Risk factors for SDG and cSDH formation were analyzed. RESULTS: Male sex, age ≥ 60 years, higher degree of arachnoid dissection, severe brain atrophy, and a large volume of subdural fluid collection (SFC) before discharge were independent risk factors for SDG formation. The risk factors for hemorrhagic conversion from SDG were continuous use or early resumption of antiplatelet drugs (odds ratio (OR): 15.367, 95% CI: 1.172-201.402) and a larger volume of SFC before discharge (OR: 0.932, 95% CI: 0.886-0.980). In the early resumption group, antiplatelet drug was resumed at a mean duration of 7.48 days postoperatively, and hemorrhagic conversion was detected earlier than that in the late resumption or no-use groups (4.09 vs. 7.18 weeks, P = 0.046). Following the receiver operating characteristic analysis, the SFC cutoff volume for hemorrhagic conversion was determined to be 23.55 mL. CONCLUSION: These findings can assist clinicians in identifying patients at a high risk of SDG and cSDH formation. Antiplatelet resumption and its timing should be determined with consideration of the risk of cSDH formation as well as individual medical conditions.

New morphological parameter for intracranial aneurysms and rupture risk prediction based on artificial neural networks.

BACKGROUND: Numerous studies have evaluated the rupture risk of intracranial aneurysms using morphological parameters because of their good predictive capacity. However, the limitation of current morphological parameters is that they do not always allow evaluation of irregularities of intracranial aneurysms. The purpose of this study is to propose a new morphological parameter that can quantitatively describe irregularities of intracranial aneurysms and to evaluate its performance regarding rupture risk prediction. METHODS: In a retrospective study, conventional morphological parameters (aspect ratio, bottleneck ratio, height-to-width ratio, volume to ostium ratio, and size ratio) and a newly proposed morphological parameter (mass moment of inertia) were calculated for 125 intracranial aneurysms (80 unruptured and 45 ruptured aneurysms). Additionally, hemodynamic parameters (wall shear stress and strain) were calculated using computational fluid dynamics and fluid-structure interaction. Artificial neural networks trained with each parameter were used for rupture risk prediction. RESULTS: All components of the mass moment of inertia (Ixx, Iyy, and Izz) were significantly higher in ruptured cases than in unruptured cases (p values for Ixx, Iyy, and Izz were 0.032, 0.047, and 0.039, respectively). When the conventional morphological and hemodynamic parameters as well as the mass moment of inertia were considered together, the highest performance for rupture risk prediction was obtained (sensitivity 96.3%; specificity 85.7%; area under the receiver operating characteristic curve 0.921). CONCLUSIONS: The mass moment of inertia would be a useful parameter for evaluating aneurysm irregularity and hence its risk of rupture. The new approach described here may help clinicians to predict the risk of aneurysm rupture more effectively.

Rupture risk prediction of cerebral aneurysms using a novel convolutional neural network-based deep learning model.

BACKGROUND: Cerebral aneurysms should be treated before rupture because ruptured aneurysms result in serious disability. Therefore, accurate prediction of rupture risk is important and has been estimated using various hemodynamic factors. OBJECTIVE: To suggest a new way to predict rupture risk in cerebral aneurysms using a novel deep learning model based on hemodynamic parameters for better decision-making about treatment. METHODS: A novel convolutional neural network (CNN) model was used for rupture risk prediction retrospectively of 123 aneurysm cases. To include the effect of hemodynamic parameters into the CNN, the hemodynamic parameters were first calculated using computational fluid dynamics and fluid-structure interaction. Then, they were converted into images for training the CNN using a novel approach. In addition, new data augmentation methods were devised to obtain sufficient training data. A total of 53,136 images generated by data augmentation were used to train and test the CNN. RESULTS: The CNNs trained with wall shear stress (WSS), strain, and combination images had area under the receiver operating characteristics curve values of 0.716, 0.741, and 0.883, respectively. Based on the cut-off values, the CNN trained with WSS (sensitivity: 0.5, specificity: 0.79) or strain (sensitivity: 0.74, specificity: 0.71) images alone was not highly predictive. However, the CNN trained with combination images of WSS and strain showed a sensitivity and specificity of 0.81 and 0.82, respectively. CONCLUSION: CNN-based deep learning algorithm using hemodynamic factors, including WSS and strain, could be an effective tool for predicting rupture risk in cerebral aneurysms with good predictive accuracy.

Acetabular fractures in elderly.

BACKGROUND: This study aimed to determine characteristics of acetabular fractures in the elderly by evaluating clinical course and computed tomography-based radiological features between low- and high-energy acetabular fractures. METHODS: We reviewed 178 consecutive patients with acetabular fractures aged ≥60 years from six centers. Low-energy fractures (group 1) were identified in 23 (12.9%) patients and high-energy fractures (group 2) in 155 (87.1%) patients. We compared demographics, radiological findings, and clinical course between the groups. RESULTS: Average age (70.6 vs. 67.8 years, p = 0.046) and ratio of females (47.8% vs. 23.2%, p = 0.021) were significantly higher in group 1 than in group 2. The Charlson comorbidity index was also higher in group 1, but no other demographics showed difference. More patients in group 2 than in group 1 underwent surgery (91.6% vs. 73.9%); however, more in group 1 underwent minimally invasive surgery (17.4% vs 4.5%). Anterior column-associated fracture patterns occurred in 91.4% and 38.7% of cases in groups 1 and 2, respectively. Most fractures were displaced (>2 mm); 68% of which were comminuted. Furthermore, 24.2% of the fractures had superior dome impaction, whereas 23.0% were associated with posterior wall impaction. CONCLUSIONS: Patients who sustained low-energy acetabular fractures were mostly women, were older, and had more comorbidities. Radiological findings of low-energy acetabular fractures showed anterior column involvement associated with injury to the quadrilateral surface. Additionally, it was observed to be commonly combined with comminution and impacted fragments.

Outcomes of dual plating for unstable distal femoral fractures: a subgroup comparison between periprosthetic and non-periprosthetic fractures.

PURPOSE: This study aimed to evaluate the outcomes of dual plating for unstable distal femoral fractures via a subgroup analysis between periprosthetic and non-periprosthetic fractures. METHODS: This retrospective cohort study analyzed the outcomes of dual plating for unstable distal femoral fractures among 49 consecutive patients (43 women and 6 men) enrolled from July 2008 to August 2020. The patients were divided into periprosthetic (group P, n = 29) and non-periprosthetic (group N, n = 20) groups. The radiographic outcomes included the mechanical lateral distal femoral angle (mLDFA) and union rate based on the computed tomography findings. The clinical parameters included the knee range of motion and knee society score (KSS). RESULTS: The mean patient age was 71.1 years, and the average follow-up period was 37 months (range, 12-138 months). Union was achieved in 47 patients (96%). The average final mLDFA was 90.5° in group P and 88.3° in group N. The average final knee range of motion was 130° in group P and 107° in group N. The average final KSS was 73.8 in group P and 87.1 in group N. CONCLUSION: Dual plating for distal femoral fractures yielded an excellent union rate and limb alignment with a low complication rate.

Percutaneous posterior transiliac plate versus iliosacral screw fixation for posterior fixation of Tile C-type pelvic fractures: a retrospective comparative study.

BACKGROUND: This study aimed to compare the clinical outcomes and complications between two minimally invasive surgical techniques: percutaneous transiliac plate fixation and iliosacral (IS) screw fixation for the treatment of Tile C-type pelvic bone fractures. METHODS: We retrospectively reviewed the data of 77 consecutive patients with Tile C pelvic ring injuries who underwent either percutaneous transiliac plate fixation or IS screw fixation in a single academic center between November 2007 and January 2018. We recorded patients' demographics, surgery-related data, and postoperative surgical outcomes and compared the incidence of complications and revision surgery rates between the two groups. RESULTS: Overall, 14 patients were included in the plate group, while 63 were included in the IS screw fixation group. No significant differences were observed in the patients' demographics between the two groups except for a longer interval from injury to surgery (13.5 days vs. 5.4 days, P = 0.001). Both groups acquired fracture union in all cases. There was one case of infection requiring surgical debridement in the plating group. Notably, nerve injury (n = 3) and implant loosening (n = 5) occurred in the IS screw group, but the difference was not significant. CONCLUSIONS: Both percutaneous posterior transiliac plating and IS screw fixation in patients with Tile C-type pelvic bone fractures showed good results. We recommend IS screw fixation as the primary treatment and propose posterior plating as treatment for sacral dysmorphism and bilateral sacral alar fractures in patients with spinopelvic dissociation. LEVEL OF EVIDENCE: III.

The clinical application of a scoring protocol to select endarterectomy or stenting for carotid artery stenosis.

Previously we described the protocol-based decision for choosing the proper surgical treatment option for carotid stenosis. The objective of this study is to describe our experiences of using this scoring protocol in the selection of endarterectomy or stenting for carotid stenosis. Between October 2014 and March 2018, the scoring protocol was applied to a total of 105 consecutive patients. Eighty (76.2%) patients had symptomatic stenosis ≥ 50%, and 25 (23.8%) patients had asymptomatic stenosis ≥ 80%. We also speculated about how effectively the protocol worked in the real clinical setting. Stenting was performed in 73 patients and endarterectomy in 32 patients. Overall, 98 (93.3%) patients were treated according to the protocol, while the protocol was violated in seven (6.7%) patients. Sixty-one (58.1%) patients received treatments that were decided by the protocol. There were 37 (35.2%) patients who had the same score for both treatment options. Among these patients, 28 patients underwent stenting and nine patients underwent endarterectomy. In the stenting cases, 90.4% of the patients followed the protocol and violations occurred in 9.6%. In the endarterectomy cases, all of the patients followed the protocol. Overall, one patient had a procedure-related complication without morbidity. During the 12-month follow-ups, there were no restenoses or major strokes. Minor strokes were diagnosed in three (2.8%) patients. In patients with carotid artery stenosis, stenting and endarterectomy should be considered simultaneously together, not against each other. Our scoring protocol can be used to weigh these options and applied in clinical practice.

Surgical outcomes of retrograde nailing enhanced with minimally invasive cerclage cable fixation for infra-isthmal femoral fracture.

BACKGROUND: Infra-isthmal femoral fracture has been known as one of the risk factors for femoral nonunion. Retrograde intramedullary nailing can provide reliable stability of the distal fragment in infra-isthmal femoral fracture, but adequate reduction is required to achieve a successful outcome. This study aimed to evaluate the surgical outcomes of retrograde nailing enhanced with minimally invasive cerclage cable fixation for infra-isthmal femoral fracture. METHODS: Between March 2013 and July 2017, 15 patients with infra-isthmal fractures treated with retrograde nailing and minimally invasive cerclage cable fixation were included in this study. Cerclage cable was applied for reduction aid (reduction cable) or prevention of further displacement in non-displaced extension of the distal spiral fracture (prevention cable). Number and function of cerclage cables, operation time, additional surgery, and complications were assessed. Further displacement of the wedge after nailing, coronal and sagittal alignment, displacement of the main fragment, and time from injury to union were evaluated as radiologic outcomes. RESULTS: Of the 15 patients in this study, 14 were treated with reduction cables. Average postoperative coronal and sagittal angulation was 1.7° (1° varus to 4° valgus) and 1.6° (2° flexion to 11° extension). Mean displacement between the main fragments was 3.5 mm (range 0-22 mm). Four of the 14 cases used additional prevention cables combined with reduction cable. Only one case was treated solely with a prevention cable. A total of five prevention cables were maintained without further displacement. All patients achieved bone union, and the average time to union was 22.7 weeks (range 9-44 weeks). There were no complications as a result of surgery, such as infection or major neurovascular injury. CONCLUSIONS: The minimally invasive cerclage cable technique could be a useful and safe enhancement in retrograde nailing for infra-isthmal femoral fracture in order to prevent further displacement and to reduce the main fracture.

Monitoring Radiation Doses during Diagnostic and Therapeutic Neurointerventional Procedures: Multicenter Study for Establishment of Reference Levels.

PURPOSE: To assess patient radiation doses during diagnostic and therapeutic neurointerventional procedures from multiple centers and propose dose reference level (RL). MATERIALS AND METHODS: Consecutive neurointerventional procedures, performed in 22 hospitals from December 2020 to June 2021, were retrospectively studied. We collected data from a sample of 429 diagnostic and 731 therapeutic procedures. Parameters including dose-area product (DAP), cumulative air kerma (CAK), fluoroscopic time (FT), and total number of image frames (NI) were obtained. RL were calculated as the 3rd quartiles of the distribution. RESULTS: Analysis of 1160 procedures from 22 hospitals confirmed the large variability in patient dose for similar procedures. RLs in terms of DAP, CAK, FT, and NI were 101.6 Gy·cm2, 711.3 mGy, 13.3 minutes, and 637 frames for cerebral angiography, 199.9 Gy·cm2, 3,458.7 mGy, 57.3 minutes, and 1,000 frames for aneurysm coiling, 225.1 Gy·cm2, 1,590 mGy, 44.7 minutes, and 800 frames for stroke thrombolysis, 412.3 Gy·cm2, 4,447.8 mGy, 99.3 minutes, and 1,621.3 frames for arteriovenous malformation (AVM) embolization, respectively. For all procedures, the results were comparable to most of those already published. Statistical analysis showed male and presence of procedural complications were significant factors in aneurysmal coiling. Male, number of passages, and procedural combined technique were significant factors in stroke thrombolysis. In AVM embolization, a significantly higher radiation dose was found in the definitive endovascular cure group. CONCLUSION: Various RLs introduced in this study promote the optimization of patient doses in diagnostic and therapeutic interventional neuroradiology procedures. Proposed 3rd quartile DAP (Gy·cm2) values were 101.6 for diagnostic cerebral angiography, 199.9 for aneurysm coiling, 225.1 for stroke thrombolysis, and 412.3 for AVM embolization. Continual evolution of practices and technologies requires regular updates of RLs.

Source Image Based New 3D Rotational Angiography for Differential Diagnosis between the Infundibulum and an Internal Carotid Artery Aneurysm : Pilot Study.

OBJECTIVE: Distinguishing between an infundibulum and a true aneurysm is clinically important. This study aimed to evaluate whether using source image based new three-dimensional rotational angiography (S-n3DRA) can increase the rate of aneurysm detection and improve distinction between a true aneurysm and an infundibulum. METHODS: Twenty-two consecutive patients with 23 lesions, were evaluated by time-of-flight (TOF) magnetic resonance angiography (MRA), S-n3DRA, and digital subtraction angiography (DSA). The data were retrospectively and independently reviewed by two neurointerventionists, and the diagnoses based on TOF MRA, S-n3DRA, and DSA were compared. The diagnostic efficacy (interobserver agreement and diagnostic performance) of S-n3DRA was compared with that of TOF MRA. RESULTS: S-n3DRA showed higher interobserver agreement (κ=0.923) than TOF MRA (κ=0.465) and significantly higher accuracy than MRA in distinguishing an aneurysm from an infundibulum (p=0.0039). CONCLUSION: Compared to MRA, S-n3DRA could provide better screening accuracy and information for distinguishing an aneurysm from an infundibulum. Therefore, S-n3DRA has the potential to reduce the need for DSA.