Safety and efficacy of stent-assisted coil embolization with periprocedural dual antiplatelet therapy for the treatment of acutely ruptured intracranial aneurysms.

PURPOSE: Despite growing evidence for the effectiveness of stent-assisted coil embolization (SAC) in treating acutely ruptured aneurysms, the safety of stent placement in acute phase remains controversial because of concerns for stent-induced thromboembolism and hemorrhagic events attributable to the necessity of antiplatelet therapy. Therefore, we investigated the safety and efficacy of SAC with periprocedural dual antiplatelet therapy (DAPT) compared with the coiling-only technique to determine whether it is a promising treatment strategy for ruptured aneurysms. METHODS: We retrospectively evaluated 203 enrolled patients with acutely ruptured aneurysms, categorizing them into two groups: SAC and coiling-only groups. Comparative analyses between the two groups regarding angiographic results, clinical outcomes, and procedure-related complications were performed. A subgroup analysis of procedural complications was conducted on patients who did not receive chronic antithrombotic medications to alleviate their influence before hospitalization. RESULTS: 130 (64.0%) patients were treated using the coiling-only technique, whereas 73 (36.0%) underwent SAC. There was a trend to a higher complete obliteration rate (p = 0.061) and significantly lower recanalization rate (p = 0.030) at angiographic follow-up in the SAC group compared to the coiling-only group. Postprocedural cerebral infarction occurred less frequently in the SAC group (8.2%) than in the coiling-only group (17.7%), showing a significant difference (p = 0.044). Although the ventriculostomy-related hemorrhage rate was significantly higher in the SAC group than in the coiling-only group (26.2% vs. 9.3%, p = 0.031), the incidence of symptomatic ventriculostomy-related hemorrhage was comparable. Subgroup analysis excluding patients receiving chronic antithrombotic medications showed similar results. CONCLUSION: SAC with periprocedural DAPT could be a safe and effective treatment strategy for acutely ruptured aneurysms. Moreover, it might have a protective effect on postprocedural cerebral infarction without increasing the risk of symptomatic hemorrhagic complications.

Imaging follow-up strategy after endovascular treatment of Intracranial aneurysms: A literature review and guideline recommendations.

OBJECTIVE: Endovascular coil embolization is the primary treatment modality for intracranial aneurysms. However, its long-term durability remains of concern, with a considerable proportion of cases requiring aneurysm reopening and retreatment. Therefore, establishing optimal follow-up imaging protocols is necessary to ensure a durable occlusion. This study aimed to develop guidelines for follow-up imaging strategies after endovascular treatment of intracranial aneurysms. METHODS: A committee comprising members of the Korean Neuroendovascular Society and other relevant societies was formed. A literature review and analyses of the major published guidelines were conducted to gather evidence. A panel of 40 experts convened to achieve a consensus on the recommendations using the modified Delphi method. RESULTS: The panel members reached the following consensus: 1. Schedule the initial follow-up imaging within 3-6 months of treatment. 2. Noninvasive imaging modalities, such as three-dimensional time-of-flight magnetic resonance angiography (MRA) or contrast-enhanced MRA, are alternatives to digital subtraction angiography (DSA) during the first follow-up. 3. Schedule mid-term follow-up imaging at 1, 2, 4, and 6 years after the initial treatment. 4. If noninvasive imaging reveals unstable changes in the treated aneurysms, DSA should be considered. 5. Consider late-term follow-up imaging every 3-5 years for lifelong monitoring of patients with unstable changes or at high risk of recurrence. CONCLUSIONS: The guidelines aim to provide physicians with the information to make informed decisions and provide patients with high-quality care. However, owing to a lack of specific recommendations and scientific data, these guidelines are based on expert consensus and should be considered in conjunction with individual patient characteristics and circumstances.

Predictive Factors of First-Pass Effect in Patients Who Underwent Successful Endovascular Thrombectomy for Emergent Large Vessel Occlusion.

OBJECTIVE: The primary treatment goal of current endovascular thrombectomy (EVT) for emergent large-vessel occlusion (ELVO) is complete recanalization after a single maneuver, referred to as the 'first-pass effect' (FPE). Hence, we aimed to identify the predictive factors of FPE and assess its effect on clinical outcomes in patients with ELVO of the anterior circulation. METHODS: Among the 129 patients who participated, 110 eligible patients with proximal ELVO (intracranial internal carotid artery and proximal middle cerebral artery) who achieved successful recanalization after EVT were retrospectively reviewed. A comparative analysis between patients who achieved FPE and all others (defined as a non-FPE group) was performed regarding baseline characteristics, clinical variables, and clinical outcomes. Multivariate logistic regression analyses were subsequently conducted for potential predictive factors with p<0.10 in the univariate analysis to determine the independent predictive factors of FPE. RESULTS: FPE was achieved in 31 of the 110 patients (28.2%). The FPE group had a significantly higher level of functional independence at 90 days than did the non-FPE group (80.6% vs. 50.6%, p=0.002). Pretreatment intravenous thrombolysis (IVT) (odds ratio [OR], 3.179; 95% confidence interval [CI], 1.025-9.861; p=0.045), door-to-puncture (DTP) interval (OR, 0.959; 95% CI, 0.932-0.987; p=0.004), and the use of balloon guiding catheter (BGC) (OR, 3.591; 95% CI, 1.231-10.469; p=0.019) were independent predictive factors of FPE. CONCLUSION: In conclusion, pretreatment IVT, use of BGC, and a shorter DTP interval were positively associated with FPE, increasing the chance of acquiring better clinical outcomes.

Distal placement of balloon guide catheter facilitates stent-retriever mechanical thrombectomy for acute ischemic stroke in the anterior circulation.

PURPOSE: Although balloon guide catheters (BGCs) have been demonstrated to improve recanalization and functional outcomes by enabling proximal flow control and forced aspiration during mechanical thrombectomy (MT), the significance of the BGC location has been overlooked. We evaluated the impact of BGC location during MT for anterior circulation acute ischemic stroke (AIS). METHODS: Patients were divided into the proximal and distal BGC groups according to the BGC tip location relative to the lower margin of the C1 vertebral body. Endovascular and clinical outcomes were compared between the two groups, including subgroup analyses of the two types of extracranial internal carotid artery (ICA) anatomy, categorized based on cerebral angiography. RESULTS: A total of 124 patients were analyzed, with 62 each in the proximal and distal BGC placement groups. The distal BGC group had higher rates of first-pass recanalization (FPR) (38.7% vs. 17.7%, P = 0.009) and favorable outcomes (64.5% vs. 46.8%, P = 0.047) with shorter procedure time (47.5 min vs. 65 min, P = 0.001) and fewer distal embolization (3.2% vs. 12.9%, P = 0.048) than the proximal BGC group. FPR was also more frequently achieved in the distal BGC group of patients with tortuous ICA (37.0% vs. 12.5%, P = 0.029). Multivariate analysis showed that distal BGC placement was an independent predictor of FPR (odds ratio, 3.092; 95% confidence interval, 1.326-7.210; P = 0.009). CONCLUSION: Distal BGC placement facilitates MT for AIS in the anterior circulation. Therefore, we suggest distal BGC placement to maximize the effect of thrombectomy, even for tortuous extracranial ICA.

Factors predicting good prognosis of failed intra-arterial thrombectomy cases: A retrospective study.

Intra-arterial thrombectomy (IAT) has been increasingly applied in the treatment of acute ischemic stroke (AIS) due to large-vessel occlusion, and many related studies have been published. However, limited studies on the prognosis of failed-IAT patients are available. In this study, factors that can predict a good prognosis in patients with failed IAT were studied. Among patients who visited our hospital between January 2016 and September 2022 and underwent IAT, we retrospectively analyzed those with failed IAT. A univariate analysis was performed on the radiological features, medical histories, and other patient characteristics expected to affect the prognosis, and a multivariate analysis was performed on some of these factors. In univariate analysis, a good collateral channel on susceptibility-weighted imaging (SWI), modified thrombolysis in cerebral infarction (mTICI) 2A recanalization, and the pre-procedural modified Rankin scale (mRS) were statistically significant. In the multivariate analysis, good collateral channels on SWI and computed tomography angiography (CTA) and mTICI 2A recanalization were statistically significant. Factors that can predict a good prognosis in patients with failed IAT include good leptomeningeal collateral channels evaluated by CTA and SWI and mTICI 2A recanalization.

Outcomes Following Carotid Endarterectomy and Carotid Artery Stenting in Patients with Carotid Artery Stenosis: A Retrospective Study from a Single Center in South Korea.

BACKGROUND Previous randomized controlled trials and meta-analyses comparing carotid endarterectomy (CEA) and carotid artery stenting (CAS) included a large number of patients, but the diagnosis, treatment selection, and performance were heterogeneous. This retrospective study from a single center in South Korea aimed to evaluate outcomes following CEA and CAS in patients with carotid artery stenosis. MATERIAL AND METHODS A retrospective analysis was performed using the data of patients who underwent carotid revascularization between September 2016 and June 2021 at a single institution. The primary outcomes were stroke, myocardial infarction (MI), and death during the periprocedural period. RESULTS We enrolled a total of 61 (44 symptomatic and 17 asymptomatic) patients who underwent CEA or CAS. Among them, 36 (59%) underwent CEA and 25 (41%) underwent CAS. Statistically significant differences were found between the groups in degree of carotid stenosis (CEA: 87.0±9.1, CAS: 80.5±9.3, P=0.007). All patients with confirmed plaque ulceration before carotid revascularization underwent CEA. Two (3.3%) periprocedural strokes occurred, 1 in each group, on the ipsilateral side. There were no significant differences between CEA and CAS in the event-free survival rate for stroke during the follow-up (log-rank test=0.806). CONCLUSIONS Favorable outcomes in terms of periprocedural stroke were observed. We found no significant difference between the 2 carotid revascularization techniques in the incidence of periprocedural stroke in symptomatic and asymptomatic patients. To confirm our findings, further studies involving a larger number of patients and continuous follow-up are necessary.

Predictors of intracranial hemorrhage after mechanical thrombectomy using a stent-retriever for anterior circulation ischemic stroke: A retrospective study.

Intracranial hemorrhage (ICH) after mechanical thrombectomy (MT) is a potentially catastrophic complication. We aimed to identify predictors of hemorrhagic complications following MT using a stent-retriever (SR) for acute ischemic stroke (AIS) patients due to large vessel occlusion of anterior circulation. In consecutive AIS patients, the clinical and procedural variables were retrospectively analyzed. ICH was evaluated on computed tomography performed 24 hours following MT and dichotomized into asymptomatic ICH and symptomatic intracranial hemorrhage (SICH) depending on the presence of neurological deterioration. Using univariate and multivariate analyses, the predictors of ICH and SICH were identified. The optimal cutoff value for predicting SICH was determined by receiver operating characteristic (ROC) analysis. Among 135 patients, ICH was detected in 52 (38.5%), and 17 (12.6%) were classified as having SICH. We found that serum glucose level (odds ratio [OR] 1.016, P = .011) and number of SR passes (OR 2.607, P < .001) were significantly correlated with ICH. Independent predictors of SICH included the baseline Alberta stroke program early computed tomography score (ASPECTS) (OR 0.485, P = .042), time from stroke onset to groin puncture (OTP) (OR 1.033, P = .016), and number of SR passes (OR 2.342, P = .038). In ROC analysis, baseline ASPECTS ≤ 7, OTP > 280 minutes, and SR passes > 3 were the optimal cutoff values for predicting SICH. In conclusion, serum glucose level and SR pass serve as predictors for any form of ICH in large vessel occlusion-induced AIS patients undergoing MT. Moreover, patients with lower ASPECTS, prolonged OTP, and multiple SR passes are more vulnerable to SICH.

Predictive Factors of Surgical Site Infection Following Cranioplasty: A Study Including 3D Printed Implants.

In patients who have undergone decompressive craniectomy (DC), subsequent cranioplasty is required to reconstruct cranial defects. Surgical site infection (SSI) following cranioplasty is a devastating complication that can lead to cranioplasty failure. The aim of the present study, therefore, was to identify predictive factors for SSI following cranioplasty by reviewing procedures performed over a 10-year period. A retrospective analysis was performed for all patients who underwent cranioplasty following DC between 2010 and 2020 at a single institution. The patients were divided into two groups, non-SSI and SSI, in order to identify clinical variables that are significantly correlated with SSI following cranioplasty. Cox proportional hazards regression analyses were then performed to identify predictive factors associated with SSI following cranioplasty. A total of 172 patients who underwent cranioplasty, including 48 who received customized three-dimensional (3D) printed implants, were enrolled in the present study. SSI occurred in 17 patients (9.9%). Statistically significant differences were detected between the non-SSI and SSI groups with respect to presence of fluid collections on CT scans before and after cranioplasty. Presence of fluid collections on computed tomography (CT) scan before (p = 0.0114) and after cranioplasty (p < 0.0000) showed significant association with event-free survival rate for SSI. In a univariate analysis, significant predictors for SSI were fluid collection before (p = 0.0172) and after (p < 0.0001) cranioplasty. In a multivariate analysis, only the presence of fluid collection after cranioplasty was significantly associated with the occurrence of SSI (p < 0.0001). The present study investigated predictive factors that may help identify patients at risk of SSI following cranioplasty and provide guidelines associated with the procedure. Based on the results of the present study, only the presence of fluid collection on CT scan after cranioplasty was significantly associated with the occurrence of SSI. Further investigation with long-term follow-up and large-scale prospective studies are needed to confirm our conclusions.

Gender differences in adult traumatic brain injury according to the Glasgow coma scale: A multicenter descriptive study.

PURPOSE: Patients' gender, which can be one of the most important determinants of traumatic brain injury (TBI) outcomes, is also likely to interact with many other outcome variables of TBI. This multicenter descriptive study investigated gender differences in epidemiological, clinical, treatment, mortality, and variable characteristics in adult TBI patients. METHODS: The selection criteria were defined as patients who had been diagnosed with TBI and were admitted to the hospital between January 1, 2016 and December 31, 2018. A total of 4468 adult TBI patients were enrolled at eight University Hospitals. Based on the list of enrolled patients, the medical records of the patients were reviewed and they were registered online at each hospital. The registered patients were classified into three groups according to the Glasgow coma scale (GCS) score: mild (13-15), moderate (9-12), and severe (3-8), and the differences between men and women in each group were investigated. The risk factors of moderated and severe TBI compared to mild TBI were also investigated. RESULTS: The study included 3075 men and 1393 women and the proportion of total males was 68.8%. Among all the TBI patients, there were significant differences between men and women in age, past history, and GCS score. While the mild and severe TBI groups showed significant differences in age, past history, and clinical symptoms, the moderate TBI group showed significant differences in age, past history, cause of justice, and diagnosis. CONCLUSION: To the best of our knowledge, this multicenter study is the first to focus on gender differences of adult patients with TBI in Korea. This study shows significant differences between men and women in many aspects of adult TBI. Therefore, gender differences should be strongly considered in TBI studies.

Color Doppler ultrasonography for predicting the patency of anastomosis after superficial temporal to middle cerebral artery bypass surgery.

BACKGROUND: Color Doppler ultrasonography (CDUS) is used to evaluate the surgical success and postoperative hemodynamic changes of patients who receive superficial temporal to middle cerebral artery (STA-MCA) bypass surgery. Previous studies enrolled small populations, and difficulties interpreting the results have limited their use in clinical settings. OBJECTIVE: We attempted to determine the feasibility of using CDUS to evaluate STA hemodynamics and identify the most reliable parameter as a new clinical implication for determining bypass patency. METHOD: Twenty-six patients who underwent STA-MCA bypass surgery were prospectively enrolled. Four times CDUS and two times digital subtraction angiography (DSA) were performed. The CDUS parameters were compensated using the ratio of the operated to the non-operated sides (R1) and compared before and after surgery (R2). The CDUS parameters are then compared with the patency on DSA by statistical analyses. RESULTS: Increased CDUS parameters of the mean flow rate (MFR) and cross-sectional diameter (CSD) showed significant correlations with good patency on DSA. The R2 at 1 month was identified as the most reliable parameter for predicting the patency in both MFR and CSD. Their cutoff values were 1.475 and 1.15, respectively. CONCLUSION: CDUS can be utilized for predicting the patency after STA-MCA bypass surgery; if the postoperative (compensated and compared) CDUS parameters increased by more than 47.5% in the MFR or 15% in the CSD, the patency of the anastomosis on DSA would be good.

Paraspinal muscle changes after single-level posterior lumbar fusion: volumetric analyses and literature review.

BACKGROUND: Posterior lumbar fusion is a widely accepted surgical technique; however, it has been related to the possibility of paraspinal muscle atrophy after surgery. We investigated 1-year postoperative changes in paraspinal muscle volume using a simple formula applicable to magnetic resonance imaging (MRI) or computed tomography (CT) images. METHODS: Patients with degenerative lumbar spinal stenosis who underwent posterior interbody fusion (PLIF) at the L4/5 level in the period from May 2010 to June 2017 were enrolled in this study. Radiologic parameters were measured using MRI or CT images which were taken before surgery and at 1 year after surgery. The volume of the paraspinal muscles was calculated using a simple formula which was derived from the formula for calculating the volume of truncated elliptic cones. RESULTS: A total of 40 patients were included; 24 were analyzed using MRI and 16 were analyzed using CT. The mean age of the patients was 59.6 ± 12.1 years and 32 (80.5%) were female. When comparing the preoperative and 1-year-postoperative images, multifidus muscle (MF) reduction was consistently observed in the MRI and CT groups, right and left (p = 0.003, p < 0.001, p = 0.005 and p < 0.001, respectively). In the erector spinae (ES) group, decrease in muscle volume was observed in the right-sided muscles of the CT group (p < 0.001), but no significant change was observed in the MRI group. The psoas muscle showed no significant change after 1 year. Conversely, regression analysis showed a negative correlation between MF muscle volume loss and age in the MRI group (right and left, p = 0.002 and p = 0.015, respectively), that is, the younger the age, the greater loss of muscle mass. CONCLUSION: After the posterior lumbar fusion, the volume of the MF muscles was markedly decreased, and the degree of decrease was apparent in the MRI. The volume of the ES muscles, which are located relatively laterally, also tended to decrease at 1 year after surgery.

Segmental Motion of the Cervical Spine After Total Disc Replacement Using ActivC Versus Discectomy and Fusion Using Stand-alone Cage.

OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) has been a widely accepted procedure for the treatment of cervical disc diseases. However, due to several reports regarding postfusion exacerbation of adjacent segments, a motion-preserving prosthesis was developed. In the present retrospective analysis, total disc replacement (TDR) using ActivC (Aesculap AG, Tuttlingen, Germany) was compared with ACDF using a stand-alone cage. METHODS: Among patients diagnosed with cervical disc diseases, those who received either ACDF or TDR at a single level between C3 and C7 from January 2010 to December 2015 were reviewed. Clinical outcomes were assessed using the visual analogue scale for arm and neck pain and the neck disability index. Clinical scales, lateral neutral, and flexion-extension radiographs were taken for all patients preoperatively and 2 months, 6 months, 1 year, and 2 years postoperatively. Global lordosis, C2-C7 Sagittal vertical axis, and T1 slope were measured on lateral neutral radiographs. The segmental range of motion (ROM) of the operated level, cranial adjacent level, and caudal adjacent level were defined as the difference between Cobb angles on flexion-extension lateral radiographs. RESULTS: A total of 53 patients (mean age 48.5 years) were reviewed. Thirty patients were treated with ACDF and the remaining 23 patients received TDR. At the 2-year follow-up, the segmental ROM of operated level was significantly preserved in the TDR group compared with the ACDF group (P = 0.007). Conversely, no significant differences in the ROM at the adjacent segments were observed between the TDR and ACDF groups (P > 0.05). The clinical outcome was excellent in both ACDF and TDR groups and was maintained until the 2-year follow-up. CONCLUSIONS: In the present study, TDR using ActivC showed successful motion preservation at the operated level and equivalent results were observed with ACDF based on clinical and radiologic results.

Posterior circulation involvement and collateral flow pattern in moyamoya disease with the RNF213 polymorphism.

PURPOSE: Moyamoya disease is a chronic cerebrovascular disorder characterized by progressive stenosis of the circle of Willis with a compensatory collateral vessel network. Recent studies have identified the ring finger protein 213 gene (RNF213) as the unique susceptibility gene for moyamoya disease. The purpose of this study was to compare clinical features of moyamoya disease, especially angiographic findings, between patients with and without the RNF213 mutation. METHODS: Blood samples from 35 patients with moyamoya disease were obtained between May 2016 and May 2017. Information on age at the time of diagnosis, sex, and initial symptom were obtained via retrospective chart review. Angiographic records were evaluated. RESULTS: RNF213 variants were detected in the 28 of 35 patients (80%), including all pediatric patients (100%) and 18 of 25 adult patients (72%) in our cohort. Leptomeningeal collateral flow from posterior to anterior circulation was more frequent in the RNF213-negative group than in the RNF213-positive group (100% versus 38.9%; p = 0.020). Posterior cerebral arterial territorial involvement was more frequently observed in RNF213-positive patients than in RNF213-negative patients (50% versus 0%; p = 0.027). CONCLUSIONS: RNF213 may play a significant role in the development of collateral anastomoses.

S100ß, Matrix Metalloproteinase-9, D-dimer, and Heat Shock Protein 70 Are Serologic Biomarkers of Acute Cerebral Infarction in a Mouse Model of Transient MCA Occlusion.

OBJECTIVE: Diagnosing acute cerebral infarction is crucial in determining prognosis of stroke patients. Although many serologic tests for prompt diagnosis are available, the clinical application of serologic tests is currently limited. We investigated whether S100ß, matrix metalloproteinase-9 (MMP-9), D-dimer, and heat shock protein 70 (HSP70) can be used as biomarkers for acute cerebral infarction. METHODS: Focal cerebral ischemia was induced using the modified intraluminal filament technique. Mice were randomly assigned to 30-minute occlusion (n=10), 60-minute occlusion (n=10), or sham (n=5) groups. Four hours later, neurological deficits were evaluated and blood samples were obtained. Infarction volumes were calculated and plasma S100ß, MMP-9, D-dimer, and HSP70 levels were measured using enzyme-linked immunosorbent assay. RESULTS: The average infarction volume was 12.32±2.31 mm3 and 46.9±7.43 mm3 in the 30- and 60-minute groups, respectively. The mean neurological score in the two ischemic groups was 1.6±0.55 and 3.2±0.70, respectively. S100ß, MMP-9, and HSP70 expressions significantly increased after 4 hours of ischemia (p=0.001). Furthermore, S100ß and MMP-9 expressions correlated with infarction volumes (p<0.001) and neurological deficits (p<0.001). There was no significant difference in D-dimer expression between groups (p=0.843). The area under the receiver operating characteristic curve (AUC) showed high sensitivity and specificity for MMP-9, HSP70 (AUC=1), and S100ß (AUC=0.98). CONCLUSION: S100ß, MMP-9, and HSP70 can complement current diagnostic tools to assess cerebral infarction, suggesting their use as potential biomarkers for acute cerebral infarction.

The Potential of Diffusion-Weighted Magnetic Resonance Imaging for Predicting the Outcomes of Chronic Subdural Hematomas.

OBJECTIVE: Diffusion-weighted magnetic resonance imaging (DW-MRI) has proven useful in the study of the natural history of ischemic stroke. However, the potential of DW-MRI for the evaluation of chronic subdural hematoma (CSDH) has not been established. In this study, we investigated DW-MRI findings of CSDH and evaluated the impact of the image findings on postoperative outcomes of CSDH. METHODS: We studied 131 CSDH patients who had undergone single burr hole drainage surgery. The images of the subdural hematomas on preoperative DW-MRI and computed tomography (CT) were divided into three groups based on their signal intensity and density: 1) homogeneous (iso or low) density on CT and homogeneous low signal intensity on DW-MRI; 2) homogeneous (iso or low) density on CT and mixed signal intensity on DW-MRI; and 3) heterogeneous density on CT and mixed signal intensity on DW-MRI. On the basis of postoperative CT, we also divided the patients into 3 groups of surgical outcomes according to residual hematoma and mass effect. RESULTS: Analysis showed statistically significant differences in surgical (A to B: p<0.001, A to C: p<0.001, B to C: p=0.129) and functional (A to B: p=0.039, A to C: p<0.001, B to C: p=0.108) outcomes and treatment failure rates (A to B: p=0.037, A to C: p=0.03, B to C: p=1) between the study groups. In particular, group B and group C showed worse outcomes and higher treatment failure rates than group A. CONCLUSION: CSDH with homogeneous density on CT was characterized by signal intensity on DW-MRI. In CSDH patients, performing DW-MRI as well as CT helps to predict postoperative treatment failure or complications.

Analysis of the Factors Affecting Surgical Site Infection and Bone Flap Resorption after Cranioplasty with Autologous Cryopreserved Bone: The Importance of Temporalis Muscle Preservation.

AIM: To investigate the outcomes and associated complications after delayed cranioplasty using autologous, cryopreserved bone. MATERIAL AND METHODS: This retrospective study included 57 consecutive patients treated with cranioplasty with autologous cryopreserved bone for various conditions causing increased intracranial pressure due to brain swelling. The incidence and risk factor of surgical site infection (SSI) and bone flap resorption were analyzed. RESULTS: The SSI rate was 12.3% and the bone flap resorption rate was 24.0%. There were statistically significant differences in SSI rate in relation to time from craniectomy to cranioplasty (p=0.002) and previous temporalis muscle resection (p=0.021). These factors were also independently associated with surgical site infection (time from craniectomy to cranioplasty: OR 0.901, 95% CI 0.826?0.982, p=0.018; previous temporalis muscle resection: OR 11.607, 95% CI 1.155?116.590, p=0.037). There was also a statistically significant difference in the bone flap resorption rate in relation to previous temporalis muscle resection (p=0.001). This factor was associated with bone flap resorption (OR 11.667, 95% CI 2.276?59.798, p=0.003). CONCLUSION: The risk of these complications particularly increased after previous temporalis muscle resection. Based on this finding, we believe that preservation of the temporalis muscle may help to decrease postoperative complications after autologous cranioplasty.

Increased Ratio of Superficial Temporal Artery Flow Rate After Superficial Temporal Artery-to-Middle Cerebral Artery Anastomosis: Can It Reflect the Extent of Collateral Flow?

OBJECTIVE: There are several ways to identify donor artery patency and success of surgery after an anastomosis of the superficial temporal artery (STA) to the middle cerebral artery (MCA). The purpose of this study was to evaluate the ratio of bilateral STA mean flow rate (MFR) with the use of color Doppler ultrasonography (CDUS) after bypass surgery and to confirm the possibility of this value as a predictor of the extent of collateral flow. METHODS: Eleven consecutive patients who had undergone STA-MCA anastomosis were included. In every case, bilateral STA MFR, mean velocity, and cross-sectional diameter were measured preoperatively and postoperatively at 1 week, 1 month, and 2 months via CDUS. We measured the bilateral STA MFR ratio changes to compensate for systemic hemodynamic variables. RESULTS: One month after surgery, 9 of the 11 patients who underwent STA-MCA anastomosis had good patency on DSA. In patients with good patency, there was a significant increase in the baseline STA MFR ratio compared with those at 1 week, 1 month, and 2 months postoperatively (2.88, 3.07, and 4.38, respectively, P < 0.05). The mean STA cross-sectional diameter ratio also was significantly increased postoperatively in the good patency group (1.35, 1.41, and 1.49, respectively, P = 0.044). In addition, the mean STA mean velocity ratio was increased postoperatively in the good patency group (1.48, 1.40, and 1.67, respectively, P = 0.042). CONCLUSIONS: We conclude that using CDUS to measure both STA MFR ratio is a potential method to predict the extent of collateral flow through an STA-MCA anastomosis.

Efficacy of superficial temporal artery-middle cerebral artery bypass in cerebrovascular steno-occlusive diseases: Hemodynamics assessed by perfusion computed tomography.

OBJECTIVES: Our purpose of this study was to assess the cerebral hemodynamic improvement with perfusion computed tomography (CT), before and after superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery in patients with cerebrovascular steno-occlusive diseases including both moyamoya disease and nonmoyamoya steno-occlusions. MATERIALS AND METHODS: Twenty-four STA-MCA bypasses were performed to 22 patients with symptomatic cerebrovascular steno-occlusive diseases, including both moyamoya disease and nonmoyamoya steno-occlusive diseases. Brain perfusion CT images were obtained before and after the bypass surgery. The relative parameters such as cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) derived from the perfusion CT were collected and analyzed to assess the efficacy of STA-MCA bypass. RESULTS: The CBF increased, and MTT decreased after the bypass surgery in both moyamoya group and nonmoyamoya group. The increase of CBF in nonmoyamoya group and the decrease of MTT delay in moyamoya group, overall group were statistically significant (P < 0.05). No significant postoperative change in CBV was noted. During the postoperative follow-up period, none of the 22 patients experienced any repeated ischemic/hemorrhagic attacks nor any newly developed neurologic deficits. CONCLUSION: The STA-MCA bypass is an effective surgical management for patients with cerebrovascular steno-occlusive diseases, such as moyamoya disease and internal carotid artery/MCA steno-occlusion. And perfusion CT can be used as an effective quantitative modality to assess the cerebral perfusion before and after the STA-MCA bypass surgery.

Single-stage Transpedicular Vertebrectomy and Expandable Cage Placement for Treatment of Unstable Mid and Lower Lumbar Burst Fractures.

STUDY DESIGN: Retrospective clinical and radiographic study. OBJECTIVE: To examine the efficacy and safety of vertebrectomy and expandable cage placement by a single-stage posterior approach for unstable mid and lower lumbar burst fractures (below the L3). SUMMARY OF BACKGROUND DATA: Patients with unstable mid and lower lumbar burst fractures require surgical treatment to relieve pain, address paralysis, and stabilize the spine to prevent further segmental deformity. However, controversy remains regarding the optimal surgical treatment. MATERIALS AND METHODS: Eleven patients underwent single-stage posterior-only vertebral column resection and vertebral body reconstruction using an expandable cage. Neurological status was classified using the American Spinal Injury Association (ASIA) Impairment Scale, whereas functional outcome was analyzed using a visual analog scale for back pain. Segmental Cobb angles were measured above and below the fractured vertebral body preoperatively, immediate postoperatively, and at the last follow-up. RESULTS: The preoperative neurological status was ASIA grade E in 2 patients, grade D in 5 patients, grade C in 2 patients, and grade B in 2 patients. Postoperatively, neurological stability was demonstrated in 3 patients (27%), and 8 (73%) showed improvement in the ASIA grade. The mean preoperative visual analog scale score was 8.3, which decreased to 4.5 postoperatively, and to 1.8 at the final follow-up. The mean preoperative segmental lordotic angle was 9.2 degrees, which increased to 16.9 degrees postoperatively, and decreased to 15.1 degrees at the last follow-up. The mean operating time was 208.8 minutes, and the mean blood loss was 1006.3 mL. Regarding surgical complications, 1 patient experienced a dural tear and 1 patient demonstrated cage subsidence. CONCLUSIONS: The results of this small series suggest the feasibility, efficacy, and safety of this surgical option for unstable mid and lower lumbar burst fractures. This technique from a single posterior approach offers several advantages over traditional anterior or combined approaches using strut graft or nonexpandable implants.