Arteriovenous shunt

动静脉分流术
  • 文章类型: Case Reports
    颅颈交界处的硬脑膜动静脉瘘(DAVF)非常罕见。颅颈交界区的解剖结构非常复杂,由髓质和脊髓以及复杂的神经血管结构组成。必须对瘘管的血管结构进行全面评估,才能为患者选择最合适的治疗方法。在这份报告中,我们描述了利用术中血管造影术对颅颈交界区DAVF进行显微手术闭塞的细微差别.一名健康状况正常的38岁男性因脑部检查异常而被转诊到我们医院。检查诊断显示,颅颈交界处有DAVF,来自升咽的喂食器,椎骨,和枕骨动脉,引流静脉主要通向罗森塔尔的基底静脉。在术中数字减影血管造影的帮助下进行了主要引流静脉的显微外科闭塞,效果良好。颅颈DAVF是一种罕见的实体。仔细评估动脉和静脉瘘点对于确定这种情况的最佳治疗方案是必要的。显微外科手术是治疗颅颈DAVF的可行且更直接的方法。
    Dural arteriovenous fistula (DAVF) of the craniocervical junction is exceptionally rare. The anatomy of the craniocervical junction area is very complex and is composed of the medulla and spinal cord along with intricate neurovascular structures. A thorough assessment of the angioarchitecture of the fistula is obligatory for choosing the most appropriate treatment for the patient. In this report, we describe the nuance of microsurgical obliteration of craniocervical junction DAVF utilizing intraoperative angiography. A 38-year-old male in a normal state of health was referred to our hospital for an abnormality in his brain checkup. Workup diagnostics showed a DAVF on the craniocervical junction area with feeders from ascending pharyngeal, vertebral, and occipital arteries, with the draining vein mainly to the basal vein of Rosenthal. Microsurgical obliteration of the main draining vein was done with the help of intraoperative digital subtraction angiography with a good outcome. Craniocervical DAVF is a rare entity. Meticulous evaluation of arterial and venous fistula points is necessary to decide the best treatment option for this case. Microsurgical obliteration is a feasible and more straightforward procedure for treating craniocervical DAVF.
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  • 文章类型: Journal Article
    小儿动静脉分流可能是具有挑战性的栓塞和过量静脉穿透的灾难性后果。此外,大多数分流器的先天性性质需要在发生(医学难治性)心力衰竭时进行新生儿干预。这里,我们根据个人经验和文献综述描述了目前的血管内治疗策略.虽然不同,动静脉畸形,硬脑膜动静脉瘘(AVF),指南针AVF,Galen动脉瘤畸形的静脉具有相同的特征,例如高输出心力衰竭和静脉高压。本教程分为关于目标的段落,Access,和治疗,尊重儿科动静脉分流之间的差异,同时保持叙事经济。
    Pediatric arteriovenous shunts can be challenging to embolize and the consequences of excess venous penetration disastrous. Moreover, the congenital nature of most shunts necessitates neonatal intervention whenever (medically refractory) heart failure occurs. Here, we describe current endovascular treatment strategies based on personal experience and literature review. While disparate, arteriovenous malformation, dural arteriovenous fistula (AVF), pial AVF, and vein of Galen aneurysmal malformation share unifying features such as high output heart failure and venous hypertension. This tutorial is divided into passages on Goals, Access, and Treatment which respect differences among pediatric arteriovenous shunts while maintaining a narrative economy.
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  • 文章类型: Journal Article
    头弓狭窄(CAS)经常复发,到目前为止,对治疗的抵抗力和干预结果尚未得到很好的验证。我们旨在评估血液透析患者接受CAS治疗的临床结果。
    截至2023年12月4日搜索电子书目来源,以确定治疗CAS后报告结果的研究。通过荟萃分析和网络荟萃分析(NMA),结合直接和间接证据,比较不同治疗方式的累积排名曲线下的优势比(OR)和表面。本系统审查是根据PRISMA-P进行的。该评论在PROSPERO(CRD42022296513)中注册。
    4项随机对照试验(RCT)和15项非RCT纳入分析。研究人群的瘘管类型不同,再狭窄或血栓形成,在出版物中观察到显著的异质性。偏倚的风险低至严重。Meta分析发现DCB和PTA在6个月和12个月的原发性通畅性之间没有显着差异(OR分别为1.16和0.60;证据确定性低)。与支架或PTA相比,STG在3、6和12个月时的结果良好(OR分别为4.28、5.13和13.12,以及4.28、5.13、13.12;证据确定性低)。关于初级通畅,治疗排名,从最高到最低,是STG(92.7%),转座(76.0%),支架(67.5%),DCB(46.3%),和PTA(64.5%)在12个月。
    尽管数据有限,低质量的证据表明,当所有替代方案都适用时,STG可能值得考虑作为主要治疗选择,考虑到它们具有更好的原发性通畅性和更高的治疗排名的潜力。
    UNASSIGNED: Cephalic arch stenosis (CAS) is often recurrent, resistant to treatment and the intervention outcome is not well validated so far. We purposed to assess the clinical outcomes of CAS treatment in patients with hemodialysis access.
    UNASSIGNED: Electronic bibliographic sources were searched up to December 4 2023 to identify studies reported outcome after treating CAS. Direct and indirect evidence was combined to compare odds ratios (OR) and surfaces under the cumulative ranking curves across the different treatment modalities through meta-analysis and network meta-analyses (NMA). This systematic review was conducted in accordance with the PRISMA-P. The review is registered in PROSPERO (CRD42022296513).
    UNASSIGNED: Four randomized controlled trials (RCTs) and 15 non-RCTs were included in the analysis. The study population differed in fistula type, restenosis or thrombosis, and significant heterogeneity was observed among the publications. The risk of bias was low to serious. Meta-analysis found no significant difference between DCB and PTA in primary patency at 6 and 12 months (OR 1.16 and 0.60, respectively; low certainty of evidence). Favorable result with STG compared to stent or PTA at 3, 6, and 12 month was observed (OR 4.28, 5.13, and 13.12, and 4.28, 5.13, 13.12, respectively; low certainty of evidence). Regarding primary patency, the treatment rankings, from highest to lowest, were STG (92.7%), transposition (76.0%), stent (67.5%), DCB (46.3%), and PTA (64.5%) at 12 months.
    UNASSIGNED: Despite data limitations, the low-quality evidence suggests that STG may merit consideration as a primary treatment option when all alternatives are applicable, given their potential for better primary patency and higher treatment ranking.
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  • 文章类型: Journal Article
    目的:自发性直接颈动脉海绵窦瘘(CCF)通常由破裂的颈动脉海绵状动脉瘤引起。我们在高容量三级转诊中心的单中心队列中研究了自发性直接CCF的治疗。报告解剖细节,治疗的技术方法,和结果。
    方法:回顾性分析2010-2022年间接受MRI和/或DSA成像随访的自发性直接CCF成人患者。我们研究了年龄,性别,临床表现,血管造影结果,治疗技术,结果,和并发症。
    结果:在80例CCF患者中,12例患者在13个疗程中接受了非创伤性直接CCF治疗(15%).中位年龄为65岁。两名患者患有潜在的结缔组织疾病。在10个案例中,直接CCF是由破裂的海绵样颈动脉动脉瘤引起的.直接CCF经血管内动脉栓塞治疗(10例),经静脉栓塞(1例),或手术(1例)。10例患者可以选择性关闭分流。两名患者接受了母体血管闭塞治疗(PVO;一名血管内;一名手术,带旁路)。并发症发生在2/12患者(17%),2例(17%)患者的永久性发病率:PVO后的三叉神经痛和手术PVO和旁路手术后的新梗死。CCF的选择性闭合没有导致发病。我们的系列中没有死亡率。
    结论:在大多数情况下,自发性直接CCF是由海绵样颈动脉动脉瘤破裂引起的。选择性关闭分流管,通常在动脉上使用线圈是可行的,取得了良好的效果。重建血管内技术是优选的,以最大程度地减少与治疗相关的神经系统并发症。
    OBJECTIVE: Spontaneous direct carotid-cavernous fistula (CCF) are usually caused by a ruptured carotid cavernous aneurysm. We studied treatment of spontaneous direct CCFs in a single-center cohort of a high-volume tertiary referral center, reporting anatomical details, technical approaches of treatment, and outcomes.
    METHODS: Adult patients with a spontaneous direct CCF treated between 2010-2022 with follow-up MRI and/or DSA imaging available were retrospectively analyzed. We studied age, sex, clinical presentation, angiographic findings, treatment techniques, outcomes, and complications.
    RESULTS: Out of 80 patients with CCFs, twelve patients were treated for a non-traumatic direct CCF (15%) in 13 sessions. Median age was 65 years. Two patients had an underlying connective tissue disorder. In 10 cases, the direct CCF was caused by a ruptured cavernous carotid aneurysm. The direct CCFs were treated by endovascular transarterial embolization (10 cases), transvenous embolization (1 case), or surgery (1 case). Selective closure of the shunt was possible in 10 patients. Two patients were treated with parent vessel occlusion (PVO; one endovascular; one surgical, with bypass). Complications occurred in 2 / 12 patients (17%), with permanent morbidity in two patients (17%): trigeminal neuralgia after PVO and new infarct after surgical PVO and bypass. Selective closure of CCF resulted in no morbidity. There was no mortality in our series.
    CONCLUSIONS: Spontaneous direct CCFs are caused by rupture of a cavernous carotid aneurysm in most cases. Selective closure of the shunt, usually feasible transarterially with coils, achieves good results. Reconstructive endovascular techniques are preferred to minimize treatment related neurological complications.
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  • 文章类型: Journal Article
    目的:评价中心性浆液性脉络膜视网膜病变(CSC)的脉络膜动脉异常。
    方法:对52例CSC患者52只眼进行回顾性分析。经过颜色和透明度调整后,合并动脉和静脉超宽视野吲哚菁绿血管造影,以比较脉络膜动脉和静脉血管系统。具体来说,我们评估了脉络膜动脉是否在没有脉络膜毛细血管(动脉粥样硬化血管;aPV)互连的情况下直接填充了脉络膜血管。然后,比较有无动脉粥样硬化血管患者的临床特点。
    结果:在52只眼中的47只(90.4%)中检测到视网膜下液下的血管。在52只眼中的8只(15.4%)中检测到动脉血管。在那八只有动脉血管的眼睛中,7(87.5%)在静脉期显示持续染色,表明它们是动静脉分流,而一只眼睛(12.5%)在静脉期显示荧光减弱,说明这条血管纯粹是动脉.动脉粥样硬化血管的患者经历了更多的CSC复发(非aPV组:2.09±1.44倍vs.aPV组:3.25±1.28倍;p=0.039)和硬脉络膜新生血管病(PNV)发展(非aPV组:2.3%vs.aPV组:37.5%,p=0.009)。
    结论:患有CSC的眼睛中动脉粥样硬化血管的存在可能代表脉络膜循环失衡和布鲁赫膜的局灶性剪切应力,导致慢性性质和PNV发展。
    OBJECTIVE: To evaluate the choroidal arterial abnormality in central serous chorioretinopathy (CSC).
    METHODS: Fifty-two eyes from 52 patients with CSC were retrospectively evaluated. Arterial and venous ultrawide-field indocyanine green angiography were merged after color and transparency adjustments to compare the choroidal arterial and venous vasculature. Specifically, we evaluated whether the choroidal arteries directly fill the pachyvessel without interconnection of choriocapillaris (arterial pachyvessel; aPV). Then, the clinical characteristics of patients with and without arterial pachyvessel were compared.
    RESULTS: Pachyvessel under subretinal fluid was detected in 47 of 52 eyes (90.4%). An arterial pachyvessel was detected in eight of 52 eyes (15.4%). Of those eight eyes with arterial pachyvessel, seven (87.5%) showed sustained staining through the venous phase, suggesting they are arteriovenous shunt, while one eye (12.5%) showed diminished fluorescence in the venous phase, suggesting this pachyvessel was purely an artery. Patients with arterial pachyvessel experienced more CSC recurrences (non-aPV group: 2.09 ± 1.44 times vs. aPV group: 3.25 ± 1.28 times; p = 0.039) and pachychoroid neovasculopathy (PNV) development (non-aPV group: 2.3% vs. aPV group: 37.5%, p = 0.009).
    CONCLUSIONS: The presence of arterial pachyvessel in eyes with CSC may represent choroidal circulatory imbalance and focal shear stress to Bruch\'s membrane, leading to a chronic nature and PNV development.
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  • 文章类型: Journal Article
    背景:瘘点的中断是治疗硬脊膜动静脉瘘(dAVFs)的目标。就完全闭塞而言,显微手术仍然是一种高效的治疗方法,复发率最低。据报道,最困难的步骤是找到瘘管部位本身,有可能延长手术的进入和时间,和增加潜在的术后手术相关并发症。术前准确检测分流和脊柱水平对于指导最佳,快速和安全的显微外科治疗。
    方法:在本文中,作者描述了一种术前血管造影方案,该方案基于42例接受微创治疗的患者的6年机构经验,可实现安全且简单的脊柱dAVF切除术.还包括两个说明性案例以支持技术描述。
    结果:在我们的血管造影方案中,通过横向投影的非减影选择性采集,研究了与感兴趣的血管畸形相关的可疑动脉。使用3D旋转血管造影术重建所得的帧。术前血管造影方案的实施允许在所有情况下使用微创方法对瘘点进行100%的术中识别。
    结论:如今,神经外科医生提倡采用微创手术和低发病率风险手术治疗脊柱dAVF.我们的术前方法通过非减法和3D重建血管造影对瘘管点进行准确的angigoraphic定位,从而实现了分流的安全和确定的闭塞。
    BACKGROUND: Interruption of the fistulous point is the goal of treatment of spinal dural arteriovenous fistulas (dAVFs). Microsurgery remains a highly efficient treatment in terms of complete occlusion with the lowest risk of recurrence rate. It is reported that the hardest step involves finding the fistulous site itself, potentially extending surgical access and time and increasing potential postoperative surgical-related complications. The accurate preoperative detection of the shunt and spinal level together is crucial for guiding optimal, fast, and safe microsurgical treatment.
    METHODS: We describe a preoperative angiographic protocol for achieving a safe and simple resection of spinal dural arteriovenous fistulas based on a 6-year institutional experience of 42 patients who underwent minimally invasive procedures. Two illustrative cases are included to support the technical descriptions.
    RESULTS: The suspected artery associated with the vascular malformation of interest is studied in our angiographic protocol through nonsubtracted selective acquisitions in lateral projection. The resulting frames are reconstructed with three-dimensional rotational angiography. The implementation of the preoperative angiographic protocol allowed 100% of intraoperative identification of the fistulous point in all cases with the use of a minimally invasive approach.
    CONCLUSIONS: Nowadays, neurosurgeons advocate for minimally invasive procedures and procedures with low morbidity risk for treatment of spinal dural arteriovenous fistulas. Our preoperative approach for accurate angiographic localization of the fistulous point through nonsubtracted and three-dimensional reconstructed angiography allowed us to achieve safe and definitive occlusion of the shunt.
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  • 文章类型: Journal Article
    意义:尽管20年的研究和新的治疗方法,糖尿病足溃疡(DFU)仍然是常见的问题,经常复发和并发症。最新进展:有报道已经观察到神经减压(ND)手术产生比标准护理(SOC)显著更少的DFU复发。对这种明显的优越性的解释尚未被理解。关键问题:微循环被认为与糖尿病周围神经病变(DPN)和DFU有关。由于纤维骨隧道中的神经肿胀和撞击,人们对参与截留神经病(EN)的DPN的认识不足。通过ND减少EN中的c纤维压缩产生表皮下毛细管流的恢复。ND研究发现改善了神经肌肉功能和表皮微循环现象,包括慢性毛细血管缺血(CCI)和压力引起的血管舒张(PIV)。目前没有推荐用于微循环受损的治疗方法。临床和动物证据表明,局部受压的周围神经的释放改善了交感神经控制下的表皮微循环。未来方向:使用神经松解术缓解神经压迫是一种基于生理学的治疗干预措施,并为阐明ND如何降低DFU复发风险提供了科学依据。将ND与当前的SOC治疗相结合可以改善DFU复发风险,难以治愈的溃疡,神经缺血伤口,截肢风险,以及由此带来的社会成本。更多使用ND用于DFU的研究,尤其是循证医学一级研究,需要确认这些初步结果。
    Significance: Despite 20 years of research and new treatment methods, diabetic foot ulcer (DFU) remains a common problem with frequent recurrences and complications. Recent Advances: There are reports that nerve decompression (ND) surgery has been observed to produce significantly fewer DFU recurrences than standard of care (SOC). The explanation of this apparent superiority has not been understood. Critical Issues: Microcirculation is understood to be involved in diabetic peripheral neuropathy (DPN) and DFU. There is an underappreciation of the participation in DPN of entrapment neuropathy (EN) due to nerve swelling and impingement in fibro-osseous tunnels. Reducing c-fiber compression in EN by ND generates recovery of subepidermal capillary flow. ND studies have found improved neuromuscular function and epidermal microcirculation phenomena, including chronic capillary ischemia (CCI) and pressure-induced vasodilatation (PIV). There is no current therapy recommended for impaired microcirculation. Clinical and animal evidence has demonstrated that release of locally compressed peripheral nerves improves the epidermal microcirculation which is under sympathetic control. Future Directions: Using epineurolysis to relieve nerve compressions is a physiology-based therapeutic intervention and provides the scientific foundation clarifying how ND reduces DFU recurrence risk. Incorporating ND with current SOC treatments could improve DFU recurrence risk, hard-to-heal ulcers, neuroischemic wounds, amputation risk, and the resulting costs to society. More studies using ND for DFU, especially evidence-based medicine Level I studies, are needed to confirm these preliminary outcomes.
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  • 文章类型: Case Reports
    由于发病率低,小儿脑和脊柱的脑动静脉分流具有挑战性,变量表示,以及与遗传综合征的关联。关于他们的自然历史的知识来自小系列的评论。为了更好地了解自然历史和干预作用,介绍了两个案例,然后回顾了文献。在第一种情况下,1例既往有颅内瘘破裂出血史的婴儿返回择期栓塞治疗2周后发现自发形成血栓的第二个静脉瘘.在第二种情况下,一个患有脊椎-脊椎瘘的5岁孩子,确定了心脏杂音的工作,并记录了诊断血管造影,6周后进行选择性栓塞,确定自发性血栓形成。在回顾有关小儿单孔脑和脊柱瘘的文献时,作者提供了一些形态学考虑因素,以确定哪些高流量瘘可能发生自发性血栓形成,从而降低与幼儿干预相关的潜在不必要风险.
    Pediatric pial arteriovenous shunts in the brain and spine are challenging to understand because of low incidence, variable presentation, and associations with genetic syndromes. What is known about their natural history comes from reviews of small series. To better understand the natural history and role for intervention, two cases are presented followed by a review of the literature. In the first case, an infant with a prior history of intracranial hemorrhage from a ruptured pial fistula returns for elective embolization for a second pial fistula which was found to be spontaneously thrombosed 2 weeks later. In the second case, a 5-year-old with a vertebro-vertebral fistula, identified on work up for a heart murmur and documented with diagnostic angiography, is brought for elective embolization 6 weeks later where spontaneous thrombosis is identified. In reviewing the literature on pediatric single-hole fistulae of the brain and spine, the authors offer some morphologic considerations for identifying which high-flow fistulae may undergo spontaneous thrombosis to decrease the potentially unnecessary risk associated with interventions in small children.
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  • 文章类型: Journal Article
    背景:经皮氧分压(TcpO2)是确定受伤组织中氧灌注的精确方法。该装置使用电化学或光学传感器。
    目的:评估糖尿病足溃疡(DFU)游离皮瓣(FFs)的TcpO2测量的有效性。
    方法:对17例接受股前外侧(ALT)-FF手术的DFU患者进行TcpO2测定,并与30例未接受FF手术的DFU患者进行比较。
    结果:在踝肱指数、糖尿病病程和血红蛋白方面观察到显著差异,肌酐,两组之间的C反应蛋白水平。两组之间的TcpO2值相似,除了术后第30天和第60天ALT-FF组的值保持<30mmHg且未增加>50mmHg。
    结论:即使皮瓣在临床上是稳定的,由于吻合期间的外膜剥离引起的交感神经切除术和由于糖尿病性多发性神经病引起的动静脉分流进展,由于其厚的脂肪组织,可能导致ALT-FF中的TcpO2值低。这得到了FF后交感神经音缓慢恢复的支持。因此,接受FF重建的DFU患者的TcpO2测量结果可能不如未接受FF重建的患者准确。
    BACKGROUND: Transcutaneous oxygen pressure (TcpO2) is a precise method for determining oxygen perfusion in wounded tissues. The device uses either electrochemical or optical sensors.
    OBJECTIVE: To evaluate the usefulness of TcpO2 measurements on free flaps (FFs) in diabetic foot ulcers (DFUs).
    METHODS: TcpO2 was measured in 17 patients with DFUs who underwent anterolateral thigh (ALT)-FF surgery and compared with 30 patients with DFU without FF surgery.
    RESULTS: Significant differences were observed in the ankle-brachial index; duration of diabetes; and haemoglobin, creatinine, and C-reactive protein levels between the two groups. TcpO2 values were similar between two groups except on postoperative days 30 and 60 when the values in the ALT-FF group remained < 30 mmHg and did not increase > 50 mmHg.
    CONCLUSIONS: Even if the flap is clinically stable, sympathectomy due to adventitia stripping during anastomosis and arteriovenous shunt progression due to diabetic polyneuropathy could lead to low TcpO2 values in the ALT-FF owing to its thick fat tissues, which is supported by the slow recovery of the sympathetic tone following FF. Therefore, TcpO2 measurements in patients with DFU who underwent FF reconstruction may be less accurate than in those who did not.
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  • 文章类型: Journal Article
    动静脉畸形(AVM)是血管形成的异常。已经建立了许多模型来理解AVM的性质。这些模型在所用血管的直径和对循环系统的影响方面具有局限性。我们的目标是建立一个AVM模型,该模型不会引起迅速和显着的血液动力学和心脏改变,但对于AVM进展的随访是可行的。16只雌性大鼠随机分为假手术组和AVM组。在AVM组中,大隐静脉和动脉使用显微外科技术相互连接。对动物进行12周的随访。监测吻合口的通畅性以及心脏的结构和血液动力学变化。对心脏和血管进行组织学分析。在后续期间,分流仍然畅通无阻。收缩压,舒张压,平均动脉压,AVM组的心率值略有下降,但无明显下降。超声心动图结果显示收缩功能影响较小,主动脉压和血流速度有轻微和不明显的变化,和最小的左心室壁扩大。小口径大隐AVM模型不会引起急性血流动力学变化。中度但进行性的改变和静脉扩张证实了AVM样特征。该模型似乎适合进一步研究进展,扩大,或AVM的不稳定。
    Arteriovenous malformation (AVM) is an anomaly of blood vessel formation. Numerous models have been established to understand the nature of AVM. These models have limitations in terms of the diameter of the vessels used and the impact on the circulatory system. Our goal was to establish an AVM model that does not cause prompt and significant hemodynamic and cardiac alterations but is feasible for follow-up of the AVM\'s progression. Sixteen female rats were randomly divided into sham-operated and AVM groups. In the AVM group, the saphenous vein and artery were interconnected using microsurgical techniques. The animals were followed up for 12 weeks. Anastomosis patency and the structural and hemodynamic changes of the heart were monitored. The hearts and vessels were histologically analyzed. During the follow-up period, shunts remained unobstructed. Systolic, diastolic, mean arterial pressure, and heart rate values slightly and non-significantly decreased in the AVM group. Echocardiogram results indicated minor systolic function impact, with slight and insignificant changes in aortic pressure and blood velocity, and minimal left ventricular wall enlargement. The small-caliber saphenous AVM model does not cause acute hemodynamic changes. Moderate but progressive alterations and venous dilatation confirmed AVM-like features. The model seems to be suitable for studying further the progression, enlargement, or destabilization of AVM.
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