Factors influencing discharge against medical advice (DAMA) in traumatic brain injury patients requiring decompressive surgery: a comprehensive analysis.

raumatic brain injury (TBI) is a significant global health concern, particularly affecting young individuals, and is a leading cause of mortality and morbidity worldwide. Despite improvements in treatment infrastructure, many TBI patients choose discharge against medical advice (DAMA), often declining necessary surgical interventions. We aimed to investigate the factors that can be associated with DAMA in TBI patients that were recommended to have surgical treatment. This study was conducted at single tertiary university center (2008-2018), by retrospectively reviewing 1510 TBI patients whom visited the emergency room. We analyzed 219 TBI surgical candidates, including 50 declining surgery (refused group) and the others whom agreed and underwent decompressive surgery. Retrospective analysis covered demographic characteristics, medical history, insurance types, laboratory results, CT scan findings, and GCS scores. Statistical analyses identified factors influencing DAMA. Among surgical candidates, 169 underwent surgery, while 50 declined. Age (60.8 ± 17.5 vs. 70.5 ± 13.8 years; p < 0.001), use of anticoagulating medication (p = 0.015), and initial GCS scores (9.0 ± 4.3 vs. 5.3 ± 3.2; p < 0.001) appeared to be associated with refusal of decompressive surgery. Based on our analysis, factors influencing DAMA for decompressive surgery included age, anticoagulant use, and initial GCS scores. Contrary to general expectations and some previous studies, our analysis revealed that the patients' medical conditions had a larger impact than socioeconomic status under the Korean insurance system, which fully covers treatment for TBI. This finding provides new insights into the factors affecting DAMA and could be valuable for future administrative plans involving national insurance.

Arterial Wall Imaging in Angiographically Occult Spontaneous Subarachnoid Hemorrhage : New Insight into the Usual Suspect.

OBJECTIVE: The etiology of angiographically occult spontaneous subarachnoid hemorrhage (AOsSAH) is unclear. Threedimensional (3D) high-resolution vessel wall magnetic resonance imaging (HVM) might be useful in detecting the hidden arterial wall angiopathy in patients with AOsSAH. We aimed to demonstrate the feasibility of HVM for detecting the arterial cause of AOsSAH. METHODS: Patients, who were diagnosed with AOsSAH in the first evaluations and underwent HVM, were enrolled. Their clinical and radiologic data were retrospectively reviewed. Especially, focal enhancement of arterial wall on HVM and repetitive catheterized angiograms were precisely compared. RESULTS: Among 251 patients with spontaneous SAH, 22 patients were diagnosed with AOsSAH in the first evaluations (8.76%). After excluding three patients who did not undergo 3D-HVM, 19 patients were enrolled and classified as convexal (n=2) or perimesencephalic (n=4), and diffuse (n=13) groups. In convexal and perimesencephalic groups, no focal enhancement on HVM and no positive findings on repetitive angiography were noted. In diffuse group, 10 patients showed focal enhancement of arterial wall on HVM (10/13, 76.9%). Repeated angiography with 3D reconstruction revealed four patients of angiographically positive causative arteriopathy and possible lesion in one case in the concordant location of intramural enhancement on 3D-HVM (5/10, 50%). Three of them were treated with endovascular stent insertion. All patients, except one, recovered with good clinical outcome (3-month modified Rankin score, 0 and 1). CONCLUSION: 3D-HVM was useful in detecting hidden true arteriopathy in AOsSAH. It may provide new insights into the etiologic investigation of AOsSAH by proving information about the arterial wall status.

Is Stent-Assisted Coil Embolization for the Treatment of Ruptured Blood Blister-Like Aneurysms of the Supraclinoid Internal Carotid Artery Effective? : An Analysis of Single Institutional Experience with Pooled Data.

OBJECTIVE: Given the high risk of rebleeding and recurrence of blood blister-like aneurysms (BBAs), we treated ruptured BBAs of the internal carotid artery (ICA) with stent-assisted coil embolization (SAC). This study aimed to evaluate the efficacy and safety of SACs. METHODS: We retrospectively reviewed clinical and radiological data from eight patients with ruptured BBAs of the supraclinoid ICA. The modified Rankin Scale (mRS) was used to assess clinical outcomes, while radiological outcomes were evaluated on angiographs. For a pooled analysis, data from literature reporting the outcomes of ruptured BBAs treated with SAC were collected and analyzed in conjunction with our data. RESULTS: In our cohort, the mean Raymond classification score was 1.57±0.53 immediately after initial endovascular treatment. There were no perioperative complications or rebleeding events during the follow-up period. The mean mRS score at patient discharge was 1.00±0.81 and improved to 0.28±0.48 by the last follow-up day. The recurrence rate was 25% with an asymptomatic presentation and successful treatment with multiple stent insertion. Pooled analysis of 76 cases of SAC revealed a complete occlusion rate immediately after treatment of 54.8%, rebleeding rate 7.94%, and recurrence rate 24.2%. Good clinical outcomes with mRS score 0-2 were observed in 89.9% by the last clinical follow-up. Total mortality rate was 7.7%. CONCLUSION: This treatment appears to not only minimize the hemodynamic burden on the fragile dome specific to this type of aneurysm, but also provides an opportunity for safe and effective treatment in recurrent cases.

Efficacy and Safety of Timely Urgent Superficial Temporal Artery-to-Middle Cerebral Artery Bypass Surgery in Patients with Acute Ischemic Stroke: A Single-Institutional Prospective Study and a Pooled Analysis.

BACKGROUND: Clinical outcome in patients with acute ischemic stroke (AIS) caused by large vessel occlusion (LVO) is not satisfactory if reperfusion treatment fails or is not tried. AIMS: We aimed to assess the efficacy and safety of urgent superficial temporal-to-middle cerebral artery (STA-MCA) bypass surgery in selected patients. METHODS: Patients who were diagnosed with LVO-induced AIS in the anterior circulation but had a failed intra-arterial thrombectomy (IAT) or were not tried due to IAT contraindications were prospectively enrolled. Timely urgent STA-MCA bypass surgery was performed if they showed perfusion-diffusion mismatch or symptom-diffusion mismatch in the acute phase of disease. Clinical and radiological data of these patients were assessed to demonstrate the safety and efficacy of urgent bypass procedures. A pooled analysis of published data on urgent bypass surgery in acute stroke patients was conducted and analyzed. RESULTS: In 18 patients who underwent timely bypass, the National Institutes of Health Stroke Scale (NIHSS) score improved from 12.11 ± 4.84 to 9.89 ± 6.52, 1 week after surgery. Three-month and long-term (9.72 ± 5.00 months) favorable outcomes (modified Rankin Scale [mRS] scores 0-2) were achieved in 50 and 75% of the patients, respectively. The pooled analysis (117 patients from 10 articles, including ours) identified favorable mRS scores in 71.79% patients at 3 months. A significant NIHSS score improvement from 11.51 ± 4.89 to 7.59 ± 5.50 was observed after surgery with significance. Major complications occurred in 3 patients (2.6%, 3/117) without mortality. CONCLUSIONS: Urgent STA-MCA bypass surgery can be regarded as a safe optional treatment to prevent cerebral infarct expansion and to improve clinical and radiological outcomes in highly selected patients.

Extra-domain B of fibronectin as an alternative target for drug delivery and a cancer diagnostic and prognostic biomarker for malignant glioma.

Extra-domain B of fibronectin (EDB-FN) is an alternatively spliced form of fibronectin with high expression in the extracellular matrix of neovascularized tissues and malignant cancer cells. In this study, we evaluated the practicality of using EDB-FN as a biomarker and therapeutic target for malignant gliomas (MGs), representative intractable diseases involving brain tumors. Methods: The microarray- and sequence-based patient transcriptomic database 'Oncopression' and tissue microarray of MG patient tissue samples were analyzed. EDB-FN data were extracted and evaluated from 23,344 patient samples of 17 types of cancer to assess its effectiveness and selectivity as a molecular target. To strengthen the results of the patient data analysis, the utility of EDB-FN as a molecular marker and target for MG was verified using active EDB-FN-targeting ultrasmall lipidic micellar nanoparticles (~12 nm), which had a high drug-loading capacity and were efficiently internalized by MG cells in vitro and in vivo. Results: Brain tumors had a 1.42-fold cancer-to-normal ratio (p < 0.0001), the second highest among 17 cancers after head and neck cancer. Patient tissue microarray analysis showed that the EDB-FN high-expression group had a 5.5-fold higher risk of progression than the EDB-FN low-expression group (p < 0.03). By labeling docetaxel-containing ultrasmall micelles with a bipodal aptide targeting EDB-FN (termed APTEDB-DSPE-DTX), we generated micelles that could specifically bind to MG cells, leading to superior antitumor efficacy of EDB-FN-targeting nanoparticles compared to nontargeting controls. Conclusions: Taken together, these results show that EDB-FN can be an effective drug delivery target and biomarker for MG.

Hemodynamic Features of Microsurgically Identified, Thin-Walled Regions of Unruptured Middle Cerebral Artery Aneurysms Characterized Using Computational Fluid Dynamics.

BACKGROUND: Thin-walled regions (TWRs) of aneurysm surfaces observed in microscopic surgery are thought to be vulnerable areas for growth and rupture of unruptured intracranial aneurysms (UIAs). OBJECTIVE: To identify hemodynamic features of TWRs of aneurysms by using computational fluid dynamics (CFD) analyses of unruptured middle cerebral artery bifurcation (MCAB) aneurysms. METHODS: Nine patients with 11 MCAB aneurysms were enrolled, and their TWRs were identified. CFD analysis was performed using 3 parameters: pressure, wall shear stress (WSS), and WSS divergence (WSSD). Each parameter was evaluated for its correspondence with TWR. RESULTS: Among 11 aneurysms, 15 TWRs were identified. Corresponding matches with CFD parameters (pressure, WSS, and WSSD) were 73.33, 46.67, and 86.67%, respectively. CONCLUSION: WSSD, a hemodynamic parameter that accounts for both magnitude and directionality of WSS, showed the highest correspondence. High WSSD might correspond with TWR of intracranial aneurysms, which are likely high-risk areas for rupture.

Comparison of stent-assisted and no-stent coil embolization for safety and effectiveness in the treatment of ruptured intracranial aneurysms.

OBJECTIVE: The safety of the stent-assisted coil embolization (SAC) technique for acutely ruptured aneurysms has not been established yet. SAC is believed to be associated with a high risk of thromboembolic and hemorrhagic complications in acute subarachnoid hemorrhage (SAH). The aim of this study was to evaluate the safety and efficacy of the SAC technique in the setting of acutely ruptured aneurysm. METHODS: A total of 102 patients who received endovascular treatment for acute SAH between January 2011 and December 2017 were enrolled. The SAC technique was performed in 38 of these patients, whereas the no-stent coil embolization (NSC) technique was performed in 64. The safety and efficacy of the SAC technique in acute SAH was evaluated as compared with the NSC technique by retrospective analysis of radiological and clinical outcomes. RESULTS: There were no significant differences in clinical or angiographic outcomes between the SAC and NSC techniques in patients with acute SAH. The rate of ventriculostomy-related hemorrhagic complications was higher in the SAC group than that in the NSC group (63.6% vs 12.5%; OR 12.25, 95% CI 1.78-83.94, p = 0.01). However, all these complications were asymptomatic and so small that they were only able to be diagnosed with imaging. CONCLUSIONS: Ruptured wide-necked aneurysms could be effectively and safely treated with the SAC technique, which showed clinical and angiographic outcomes similar to those of the NSC technique. Hence, the SAC technique with dual-antiplatelet drugs may be a viable option even in acute SAH.

Clinical Features of Patients With Spontaneous Intracranial Hypotension Complicated With Bilateral Subdural Fluid Collections.

BACKGROUND: Subdural hygromas are often found bilaterally in spontaneous intracranial hypotension (SIH). They frequently progress to chronic subdural hematomas (CSDHs), and if the hematomas are formed, it is difficult to consider SIH as an underlying cause. Whether SIH is underlying or not among the patients presenting bilateral subdural fluid collections (hygromas or CSDHs) is clinically important because the treatment strategy should be different between them. OBJECTIVES: We designed a retrospective case-control study to figure out differential clinical features of the patients presenting bilateral symptomatic subdural fluid collections owing to SIH. METHODS: Sixty-two patients with bilateral symptomatic subdural fluid collections were enrolled, and their data on general demographics, clinical courses, radiological findings, treatments, and outcomes were collected. The patients were divided into "SIH" and "Non-SIH" groups, and a simple logistic regression analysis was performed to clarify the differences between the groups. The consequent receiver operating characteristics (ROC) curve analyses were performed with the significant predictors. RESULTS: Eight patients (13%) were diagnosed with SIH. Young age (odds ratio [OR] = 0.831, 95% confidence interval [CI]: 0.743-0.929, P = .0012), no underlying disease (OR = 0.062, 95% CI: 0.007-0.544, P = .0121), radiological features of brain sagging (OR = 10.36, 95% CI: 0.912-93.411, P = .0017), pseudo-subarachnoid hemorrhage (OR = 15.6, 95% CI: 2.088-116.52, P = .0074), and small amount of fluid collections (OR = 0.719, 95% CI: 0.579-0.893, P = .0029) were significantly associated with SIH group. ROC curve analyses were performed in parameters of age and amount of fluid collection and the cut-off values for each parameter were ≤55 years old and ≤22.08 mm, respectively. Patients diagnosed with SIH underwent epidural blood patches and showed good results, except 1 patient who underwent burr-hole trephinations. CONCLUSION: Bilateral subdural fluid collections due to underlying SIH is associated with young age (≤55 years old), no underlying diseases, smaller amount of fluid collections (≤22.08 mm of depth), and radiological findings of brain sagging or pseudo-subarachnoid hemorrhages.

Defining "early" cranioplasty to achieve lower complication rates of bone flap failure: resorption and infection.

BACKGROUND: Although cranioplasty (CP) is a frequently performed and simple procedure, complications are common, particularly bone flap resorption and infection. The timing of surgery is as an important contributory factor, but the optimal timing has not been clearly determined. OBJECTIVE: We retrospectively investigated bone flap resorption and surgical site infection after CP to determine the optimal timing of surgery for reduction of complications. METHODS: The study enrolled 126 patients who underwent decompressive craniectomy (DC) and subsequent CP. Patients with bone flap resorption or surgical site infection were analyzed as the "complication" group. Receiver operating characteristic curve analysis was performed and the Youden index was used to dichotomize "early CP" and "late CP" groups. Univariate and multivariate survival analyses were performed. RESULTS: The complication group included 42 patients. The Youden index was used to identify a cutoff value for the DC-CP interval of > 44 days, and this was used to define early (< 45 days) and late (≥ 45 days) CP. Late CP was a significant risk factor in univariate and multivariate Cox regression analyses. CONCLUSION: This study showed that early CP before 45 days after DC is associated with a lower rate of bone flap resorption and surgical site infection than late CP.

Inflammation by activated macrophage-like THP-1 cells increases human dura mater cell adhesion with alteration of integrin α2 ß1 and matrix metalloproteinase.

This study was designed to investigate (i) extracellular matrix to specify adhesive substrates to human dura mater cell (hDMC); (ii) the alteration on adhesion-related molecules in hDMC; and (iii) secreted matrix metalloproteinases (MMPs) linked with extracellular matrix remodeling after exposure to inflammation. The hDMC was cultured from human dura mater tissue, and the studies were performed with hDMC after co-culturing with macrophage like THP-1 cells (Mϕ). The adhesion of co-cultured hDMC through collagen I increased 6.4-fold and through collagen IV increased 5.0-fold compared with the adhesion of naïve cells (p < 0.001). Integrin subtype α2 ß1 expression was increased 6.3-fold (p < 0.001) and α1 expression was decreased 2.0-fold (p < 0.001) in the co-cultured cells compared with the naïve cells. Co-culturing induced significant increases in MMP-1 (13.9-fold, p < 0.01), MMP-3 (7.6-fold, p < 0.01), and VEGF (VEGF: 3.8-fold, p < 0.05) expression and decreases in MMP-9 (0.1-fold, p < 0.01) compared with the sum of naïve hDMC and Mϕ values. Increased hDMC adhesion under inflammatory conditions is caused by an increased cellular affinity for collagen I and IV mediated by increased hDMC levels of integrin subtype α2 ß1 and environmental MMP-1, -3 and decreased MMP-9. Selective integrin subtype α2 ß1 inhibition assay showed 37.8% and 35.7% reduction in adhesion of co-cultured hDMC to collagen I (p < 0.001) and IV (p = 0.057), respectively. The present study provides insight into the pathological conditions related to dura mater adhesion in inflammation. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 9999:1-11, 2019.

Usefulness and Stability of Intraoperative Digital Subtraction Angiography Using the Transradial Route in Arteriovenous Malformation Surgery.

BACKGROUND: Digital subtraction angiography is the gold standard to confirm complete removal of an arteriovenous malformation (AVM) nidus. However, the transfemoral approach requires specialized instrumentation and is cumbersome and difficult to perform with the patient in the prone or decubitus position. We report the use of intraoperative digital subtraction angiography (iDSA) with the transradial approach and examine its usefulness and safety. MATERIALS AND METHODS: We retrospectively reviewed clinical features, radiologic images, surgical findings, and iDSA findings of patients with AVM who underwent surgery for nidus removal. Transradial iDSA was performed within 30 minutes for patients who required angiographic confirmation after AVM resection. This procedure was simple with the radial arterial line for blood pressure monitoring used as digital subtraction angiography catheter access route. RESULTS: Transradial iDSA was performed in 23 patients. Twelve patients were not in the general supine position during neurosurgery; 7 patients were operated on in prone position, and 5 patients were operated on in the park bench position. Remnant nidus was identified by iDSA in 2 patients, and additional measures were required. CONCLUSIONS: Intraoperative cerebral angiography during surgery for cerebral AVM could be performed safely via the transradial approach. This approach showed several merits in terms of easy access; no extra requirements, such as preoperative sheath implantation, anticoagulation during the surgery, or a radiolucent table; and usefulness in any surgical position. Further studies using this approach and comparison with the transfemoral approach are necessary.

Intracranial Aneurysms in Adult Moyamoya Disease.

BACKGROUND: The prevalence of aneurysm formation in adults with moyamoya disease (MMD) is approximately 14%, and it represents a major potential hemorrhagic risk. We aimed to study the characteristics of intracranial aneurysms occurring in patients with MMD. We retrospectively reviewed our 10-year experience of patients with intracranial aneurysms and a diagnosis of MMD at our hospital. METHODS: Imaging studies and clinical records of 211 patients who were admitted to our hospital between January 2007 and December 2016 and were diagnosed with MMD were retrospectively reviewed. Patients were divided into 2 groups: 1) MMD without intracranial aneurysms and 2) MMD with intracranial aneurysms. The 2 groups were compared using statistical analysis. Angiographic findings and clinical features of MMD-associated aneurysms were reviewed. RESULTS: There were significant differences between the 2 groups, including age and clinical presentation. Among all enrolled patients (N = 132), 11 aneurysms were discovered in 11 patients. Prevalence of intracranial aneurysms in patients with MMD was 8.3%, and the rupture rate of these aneurysms was 63.6%. We classified the 10 MMD-associated aneurysms (excluding 1 incidentally found paraclinoid aneurysm) as follows: 4 dissecting aneurysms or pseudoaneurysms and 6 hemodynamic true aneurysms. CONCLUSIONS: MMD-associated intracranial aneurysms frequently occur in patients presenting with hemorrhagic MMD and are associated with an extremely high rate of rupture. Long-standing hemodynamic stress as well as pathologic and anatomic factors might contribute to the formation of an aneurysm.

Transradial access for cerebrovascular angiography: Evaluation of palmar collateral circulation with hand angiography and its correlation with Allen test.

OBJECTIVES: Transradial cerebral angiography (TRCA) has been introduced as an alternative technique for the transfemoral access, and its use is becoming more common in the field. In this study, we retrospectively analyzed a group of patients who received TRCA, and investigated peri-procedural measurements indicating actual hand circulation, and studied their correlation with the Allen test. PATIENTS AND METHODS: A retrospective review of 168 patients whom underwent TRCA between 2015 July and 2016 July, were included in this study. Pre procedural Allen test and Doppler ultrasonography for the radial artery (RA) and ulnar artery (UA) were done. Plethysmography tests as well as pulse oximetry monitoring were done before and during the procedure and intra-procedural angiography of the forearm and hand was done for assessment of palmar circulation. RESULTS: Pre-procedural UA diameters revealed statistically significant correlation with manual Allen test results (P <0.001, r=-0.381). The DUS RA diameters, however, did not correlate with any other pre-procedural measurements. The mean contrast filling time on forearm angiography was 3.33±1.97s, and it showed statistically significant correlation with the capillary filling time of Allen tests (P<0.001, r=0.389). CONCLUSION: Manual Allen test results correlated with angiographic capillary filling of the distal hand circulation and pre-procedural UA diameters. Our results suggest that Allen test sufficiently represent the collateral circulation status prior to TRCA.

Complications Following Transradial Cerebral Angiography : An Ultrasound Follow-Up Study.

OBJECTIVE: The feasibility and usefulness of transradial catheterization for coronary and neuro-intervention are well known. However, the anatomical change in the catheterized radial artery (RA) is not well understood. Herein, we present the results of ultrasonographic observation of the RA after routine transradial cerebral angiography (TRCA). METHODS: Patients who underwent routine TRCA with pre- and post-procedure Doppler ultrasonography (DUS) of the catheterized RA were enrolled. We then recorded and retrospectively reviewed the diameter and any complicated features of the RA observed on DUS, and the factors associated with the diameter and complications were analyzed. RESULTS: A total of 223 TRCAs across 181 patients were enrolled in the current study. The mean RA diameter was 2.48 mm and was positively correlated with male gender (p<0.001) and hypertension (p<0.002). The median change in diameter after TRCA was less than 0.1 mm (range, -1.3 to 1.2 mm) and 90% of changes were between -0.8 and +0.7 mm. Across 228 procedures, there were 12 cases (5.3%) of intimal hyperplasia and 22 cases (9.6%) of asymptomatic local vascular complications found on DUS. Patients with abnormal findings on the first procedure had a smaller pre-procedural RA diameter than that of patients without findings (2.26 vs. 2.53 mm, p=0.0028). There was no significant difference in the incidence of abnormal findings for the first versus subsequent procedures (p=0.68). CONCLUSION: DUS identified the pre- and post-procedural diameter and local complications of RA. Routine TRCA seems to be acceptable with regard to identifying local complications and changes in RA diameter.

Design Principle and Loss Engineering for Photovoltaic-Electrolysis Cell System.

The effects of exchange current density, Tafel slope, system resistance, electrode area, light intensity, and solar cell efficiency were systematically decoupled at the converter-assisted photovoltaic-water electrolysis system. This allows key determinants of overall efficiency to be identified. On the basis of this model, 26.5% single-junction GaAs solar cell was combined with a membrane-electrode-assembled electrolysis cell (EC) using the dc/dc converting technology. As a result, we have achieved a solar-to-hydrogen conversion efficiency of 20.6% on a prototype scale and demonstrated light intensity tracking optimization to maintain high efficiency. We believe that this study will provide design principles for combining solar cells, ECs, and new catalysts and can be generalized to other solar conversion chemical devices while minimizing their power loss during the conversion of electrical energy into fuel.

An age-dependent alteration of the respiratory exchange ratio in the db/db mouse.

The leptin receptor-deficient db/db mouse is a rodent model of type 2 diabetes and obesity. Diabetes in db/db mice shows an age-dependent progression, with early insulin resistance followed by an insulin secretory defect resulting in profound hyperglycemia. However, there is insufficient data on agedependent changes of energy metabolism in db/db mice. We demonstrated an age-dependent decrease in the respiratory exchange ratio (RER), calculated by a ratio of VO2/VCO2, in db/db mice. The RER determined by indirect calorimetry, was 1.03 in db/db mice under 6 weeks of age, which were similar to those in heterozygote (db/+) and wild-type (+/+) mice. However, RER decreased from approximately 0.9 to 0.8 by 10 weeks of age and subsequently returned to approximately 0.9 at 22 weeks of age. The changes in RER were concurrent with the alterations in body weight and blood glucose level. However, other metabolic indicators such as glucose tolerance, changes in body fat mass, and urinary glucose levels, did not change with age. The results suggested that the energy source utilized in db/db mice changed with the age-related progression of diabetes.

Computed tomography angiography, perfusion computed tomography, and a drug-eluting stent for the treatment of in-stent restenosis of the middle cerebral artery.

The authors report a case of in-stent restenosis (ISR) of the middle cerebral artery (MCA) following bare-metal stent (BMS) deployment and subsequent treatment using a drug-eluting stent (DES). This 65-year-old woman presented with frequent transient ischemic attacks. Initial studies revealed occlusion of the left internal carotid artery and severe stenosis of the right MCA with decreased cerebral perfusion in the bilateral MCA territories. Stent-assisted angioplasty of the right MCA was performed using a BMS, and satisfactory results were obtained with no complications. Six months after the procedure the patient presented with recurrent symptoms, and workups revealed ISR with decreased cerebral perfusion. A DES was successfully placed without complications. Follow-up studies at 3 and 8 months after retreatment showed sustained luminal integrity and cerebral perfusion. A combination of CT angiography and perfusion CT exhibited the anatomical results and hemodynamic status of the stenotic lesion, and these findings coincided with the patient's clinical symptoms and the results of conventional cerebral angiography. In-stent restenosis of the MCA after placement of a BMS can be treated using a DES. A combination of CT angiography and perfusion CT can be an alternative to conventional angiography. Low-profile devices with an amelioration of trackability are essential for the further incorporation of the DES into the field of endovascular neurosurgery. More clinical experiences and long-term follow-ups are mandatory to evaluate the safety, efficacy, and durability of the DES.

Intravascular ultrasonography-guided stent angioplasty of an extracranial vertebral artery dissection.

The authors report on a case of intravascular ultrasonography (IVUS)-guided stent angioplasty for iatrogenic extracranial vertebral artery (VA) dissection in a 49-year-old man after coil embolization for an unruptured aneurysm of the right posterior inferior cerebellar artery. Insignificant dissections occurred during the procedure. Postoperatively, the patient experienced gradually worsening posterior neck pain and headache, and follow-up angiography 8 months after the coil embolization revealed expansion of the dissection. The patient underwent stent angioplasty with IVUS guidance and his symptoms improved. To the authors' knowledge, this is the first report of IVUS-guided stent angioplasty of an extracranial VA dissection. It was safe and feasible to treat extracranial VA dissections with stent placement under IVUS guidance. Intravascular environments are in real time with IVUS, and this technique is useful in the confirmation of a true lumen and evaluation of appropriate stent apposition. More clinical experience with this technique is necessary and mandatory, and devices with smaller diameters with improved trackability are essential for further introduction of IVUS into the field of endovascular neurosurgery.

Histopathological changes of testes and eyes by neutron irradiation with boron compounds in mice.

This study was performed to investigate the biological effects of boron neutron capture therapy (BNCT) on the testes and eyes in mice using HANARO Nuclear Reactor, Korea Atomic Energy Research Institute. BNCT relies on the high capacity of 10B in capturing thermal neutrons. Sodium borocaptate (BSH, 75 ppm, iv) and boronophenylalanine (BPA, 750 ppm, ip) have been used as the boron delivery agents. Mice were irradiated with neutron (flux: 1.036739E +09, Fluence 9.600200E+12) by lying flat pose for 30 (10 Gy) or 100 min (33 Gy) with or without boron carrier treatment. In 45 days of irradiation, histopathological changes of the testes and eyes were examined. Thirty-three Gy neutron irradiation for 100 min induced testicular atrophy in which some of seminiferous tubules showed complete depletion of spermatogenic germ cells. Lens epithelial cells and lens fiber were swollen and showed granular changes in an exposure time dependent manner. However, boron carrier treatment had no significant effect on the lesions. These results suggest that the examination of histopathological changes of lens and testis can be used as "biological dosimeters" for gauging radiation responses and the HANARO Nuclear Reactor has sufficient capacities for the BNCT.