Coexistence of intradural spinal arteriovenous malformation and associated developmental anomalies - report of two cases

Spinal arteriovenous malformations (AVM) have been devided into dural (Type I), intramedullary glomus (Type II), juvenile (Type III), and perimedullary direct arteriovenous fistulae (Type IV). AVMs are usually associated with subacute myelopathy in what has been known as Foix-Alajouanine syndrome. We presented two patients with two intradural spinal arteriovenous malformations associated in what we call Foix-Alajouanine syndrome. The both patient developed acute back pain and paresthesias, followed by paraplegia and incontinence. The clinical status of one patient has been improved after particle embolization for a 17 years when he deteriorated up to paraplegia after spinal angiography for follow up. Clinical status in another patient deteriorated, because particle emoblisation cannot be performed due to very descrete presentation of the feeding artery. Extensive neuroradiological examination in both patients revealed coexistence of numerous associated developmental anomalies in both patients. We conclude that arteriovenous malformations occasionally are associated with other vascular and nonvascular developmental anomalies elsewhere in the body. These findings rise attention about keep in mind the suspicion of mutual etiopathogenesis and congenital origin of these anomalies. Early timing of the diagnostic and therapeutic interventiosn are stressed to prevent or delay irreversible ishaemic myellopathy or haemorrhage. For the definitive diagnosis of spinal arteriovenous malformations and evaluation of its occlusion grade after the therapy spinal angiography is needed     

Histologic investigation of vascular malformations of the face after transarterial embolization with ethibloc and other agents

Twenty-one vascular malformations located in the facial area, 11 high-flow arteriovenous malformations and 10 slow-flow malformations, underwent combined treatment by embolization and later surgery. Embolization was performed simultaneously with superselective angiography of the branches of the external carotid artery. The new biodegradable fibrosing agent Ethibloc was used in 16 cases. Histologic examination of the surgical specimens confirmed the good target orientation by the transarterial injection of Ethibloc. Limitations of this technique are discussed. The agent proved to have thrombogenic and fibrogenic properties. Some of the vascular walls degenerated and ruptured following the embolization, but there were no instances of necrosis of interstitial tissue or skin. Embolization treatment of vascular malformations of the face was not curative, but it facilitated subsequent surgery in all examined cases.     

Arteriovenous malformation of the forehead, anterior scalp, and nasal dorsum

Management of complex and relentless large arteriovenous malformations with long term control and acceptable aesthetic results can be accomplished. This outcome requires selective intra-arterial embolization, judicious surgical resection, composite reconstruction with free tissue transfer, other ancillary procedures, or both, and careful serial follow-up examinations to rule out recurrent or persistent disease.     

Notch receptor expression in human brain arteriovenous malformations

The roles of the Notch pathway proteins in normal adult vascular physiology and the pathogenesis of brain arteriovenous malformations are not well‐understood. Notch 1 and 4 have been detected in human and mutant mice vascular malformations respectively. Although mutations in the human Notch 3 gene caused a genetic form of vascular stroke and dementia, its role in arteriovenous malformations development has been unknown. In this study, we performed immunohistochemistry screening on tissue microarrays containing eight surgically resected human brain arteriovenous malformations and 10 control surgical epilepsy samples. The tissue microarrays were evaluated for Notch 1–4 expression. We have found that compared to normal brain vascular tissue Notch‐3 was dramatically increased in brain arteriovenous malformations. Similarly, Notch 4 labelling was also increased in vascular malformations and was confirmed by western blot analysis. Notch 2 was not detectable in any of the human vessels analysed. Using both immunohistochemistry on microarrays and western blot analysis, we have found that Notch‐1 expression was detectable in control vessels, and discovered a significant decrease of Notch 1 expression in vascular malformations. We have demonstrated that Notch 3 and 4, and not Notch 1, were highly increased in human arteriovenous malformations. Our findings suggested that Notch 4, and more importantly, Notch 3, may play a role in the development and pathobiology of human arteriovenous malformations.     

Combined use of digital subtraction angiography and MRI for radiosurgery and stereoencephalography

The authors report their experience with the combined use of digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) for the stereotactic placement of intracerebral electrodes in epilepsy and for the radiosurgical treatment of otherwise inoperable arteriovenous malformations of the brain. Both imaging techniques, when used in conjunction, have been found most useful and complementary. For deep electrode placement, they permit optimal visualization of the cerebral structures to be reached by the electrode array while allowing the avoidance of vessels in the vicinity. For radiosurgery of arteriovenous malformations, DSA provides optimal visualization of the feeders and of the malformation itself, while the MRI reveals the cerebral structures to be spared by the photon beam of the linear accelerator. A discussion of their respective roles is presented, with the specific question as to whether MRI alone could be used for both procedures.     

Proposed local diagnostic reference levels in angiography and interventional neuroradiology and a preliminary analysis according to the complexity of the procedures

The aim of this study was to propose local diagnostic reference levels (DRL) for exposure to radiation during diagnostic procedures and neuroradiological interventions such as cerebral angiography and embolisation of cerebral aneurysms (intra-cranial aneurysms and arteriovenous malformations). Hospitals should adopt the national DRLs for use locally or establish their own DRLs based on local practice, if sufficient local data are available.For this purpose we studied a sample of 113 cerebral angiography procedures and 82 embolisations of cerebral aneurysms. The data recorded included the kerma-area product (KAP), the fluoroscopy time and the number of frames for each procedure: third quartiles from the total dosimetric databank were calculated and proposed as provisional local DRL. Since the complexity of a procedure must be taken into account when evaluating the radiation dose, in the case of embolisation of aneurysms (intra-cranial), in this initial phase we assessed whether the complexity of the embolisation procedure is related to the size of the aneurysm and/or its site. We, therefore, re-calculated the DRL for only intra-cranial aneurysms, leaving aside the arteriovenous malformations. Considering that the DRL calculated for all the therapeutic procedures are similar to those calculated considering only intra-cranial aneurysms, at the moment we propose, besides the DRL for cerebral angiography, a single DRL for all interventional procedures, even when the clinical pictures are very different. Local preliminary DRLs were proposed as follows: 180 Gy cm², 12 min and 317 frames for cerebral angiography and 487 Gy cm², 46 min and 717 frames for interventional procedures (intra-cranial aneurysms and arteriovenous malformations).     

Rat model of pulmonary arteriovenous malformations after right superior cavopulmonary anastomosis

We developed a rat model of pulmonary arteriovenous malformations after cavopulmonary anastomosis. We sought to determine whether this model reproduces the angiographic and histologic features seen in the human condition. Eight Sprague-Dawley rats underwent a right superior cavopulmonary anastomosis with the use of microsurgical techniques. Between 2 and 13 mo, pulmonary angiography was performed, the animals were euthanized, and the lungs were removed. Microscopic sections of the lung were stained with an endothelial-specific antibody (von Willebrand factor). Microvessel density was determined by counting vessels staining positively for von Willebrand factor, and the shunted and nonshunted (control) lungs were compared for each animal. Pulmonary angiography revealed time-dependent development of arteriovenous malformations. Microvessel density demonstrated a time-dependent increase in the shunted lung compared with the control lung (simple linear regression of the ratio of the microvessel density of the shunted lung divided by the microvessel density of the control lung on time; R(2) = 0.79, P = 0.003). This animal model reproduces the same angiographic and microscopic features of pulmonary arteriovenous malformations that develop in humans after cavopulmonary anastomosis. This appears to be a valid model that may be used to further study etiologic mechanisms for this phenomenon.     

介入栓塞术在急诊难治性医源性肾出血中的临床应用价值

摘要 目的：探讨介入栓塞术在急诊难治性医源性肾出血中的临床应用价值。方法：收集2012年6月至2021年6月南京医院大学第一附属医院收治的72例急诊难治性医源性肾出血的患者。所有患者在保守治疗无效的情况下,行介入下肾动脉血管造影,根据造影表现确定出血责任动脉,并行栓塞治疗,术后观察临床止血的有效性及安全性。结果：72例患者,介入血管造影呈阳性结果64例,包括血管出现单纯造影剂外溢12例,单纯假性动脉瘤19例,单纯动静脉瘘8例,9例患者合并两种造影表现,以及16例患者呈现动脉出血的一些间接征象。阳性出血患者介入栓塞技术成功率及临床止血率为100%。72例患者介入术后3 d血白细胞、血中性粒细胞比率、血红蛋白、血细胞比容及血小板较术前明显升高（均P＜0.05）,血肌酐及尿素氮较介入术前轻度升高（均P＞0.05）;其中30例患者介入术后7 d再次检测血肌酐及尿素氮,较介入术前基本恢复正常（均P＞0.05）。住院期间所有患者未出现肾衰等严重的术后并发症。结论：介入栓塞术治疗急诊难治性医源性肾出血患者,具有安全、高效、并发症少等优点,临床上值得推广应用。     

Histologic change of arteriovenous malformations of the face and scalp after free flap transfer

In three patients with long-standing vascular malformations of the face and scalp, radial forearm free flaps were transferred after a near-total excision of the lesion. All patients had typical high-flow malformations with thrill and bruit. The onset and progression of the malformations were analyzed through clinical and histologic studies. After free flap transfer, the vascular malformations were followed up grossly and histologically for between 4 and 9 years. There was no recurrence of arteriovenous malformation after free flap transfer. The portion of the residual lesion adjacent to the transferred free flap disappeared, and the remaining discoloration also vanished grossly. Histologic comparison of immediate postoperative and 4-month postoperative specimens from the margin and residual lesion using Victoria blue staining showed that the typical preoperative findings for arteriovenous malformation-an intermingling of thick-walled vessels with abundant elastic fibers and thin-walled vessels without elastic fibers-had undergone change, resulting in the disappearance of the thick-walled vessels and leaving only homogeneous, thin-walled vasculature. The highly vascularized free flap, which does not contain abnormal fistulas, impacted the histologic change of the arteriovenous malformation by blocking the vicious cycle of ischemia and anatomic replacement of disfigured skin and subcutaneous tissues.     

Stroke in hereditary hemorrhagic telangiectasia patients. New evidence for repeated screening and early treatment of pulmonary vascular malformations: two case reports

Background  

Paradoxical embolism due to pulmonary arteriovenous malformations is the main mechanism of brain infarction in patients with hereditary hemorrhagic telangiectasia. International Guidelines have recently been published to clarify the performance of screening tests and the effectiveness of treatment for pulmonary arteriovenous malformations.     

Linear accelerator radiosurgery of arteriovenous malformations

Forty-five patients affected by cerebral arteriovenous malformations not suitable to open surgery have been treated by a radiosurgical technique employing a linear accelerator. One-year follow-up angiography is available for 10 cases. Therapeutic effect of focalized irradiation is presented.     

Radiation dose to the brain and subsequent risk of developing brain tumors in pediatric patients undergoing interventional neuroradiology procedures

Radiation dose to the brain and subsequent lifetime risk of diagnosis of radiation-related brain tumors were estimated for pediatric patients undergoing intracranial embolization. Average dose to the whole brain was calculated using dosimetric data from the Radiation Doses in Interventional Radiology Study for 49 pediatric patients who underwent neuroradiological procedures, and lifetime risk of developing radiation-related brain tumors was estimated using published algorithms based on A-bomb survivor data. The distribution of absorbed dose within the brain can vary significantly depending on field size and movement during procedures. Depending on the exposure conditions and age of the patient, organ-averaged brain dose was estimated to vary from 6 to 1600 mGy. The lifetime risk of brain tumor diagnosis was estimated to be increased over the normal background rates (57 cases per 10,000) by 3 to 40% depending on the dose received, age at exposure, and gender. While significant uncertainties are associated with these estimates, we have quantified the range of possible dose and propagated the uncertainty to derive a credible range of estimated lifetime risk for each subject. Collimation and limiting fluoroscopy time and dose rate are the most effective means to minimize dose and risk of future induction of radiation-related tumors.     

Interventional radiological treatment of non-colorectal liver metastases

Transcatheter treatment was performed in 81 patients with unresectable non-colorectal liver metastases. Effectiveness increased in the following order: hepatic artery infusion--arterial chemoembolization--combined, arterial and portal vein oily chemoembolization. The mean survival rates for these methods were 8.2 +/- 5.3, vs 11.7 +/- 12.9 vs 13.6 +/- 6.8 mo, and 1-year survival rates 29% vs 46% vs 65%, respectively. Chemoembolization with doxorubicin-in-oil and gelatin sponge was the most effective technique. Interventional radiological procedures were effective in neuroendocrine liver metastases. The mean survival, 1- and 3-year survival rates were as high as 34 mo, 100% and 80%, respectively, for hepatic metastases from resected malignant carcinoid tumors. Also good results were achieved after chemoembolization of metastatic ovarian carcinoma and arterial infusion for gastric carcinoma metastatic to the liver. Transcatheter treatment was ineffective in liver metastases from pancreatic carcinoma, gallbladder cancer, and unknown (and non-resected) tumors. The initial results of the use of interventional radiological procedures in non-colorectal liver metastases are promising, so following clinical trails are needed.     

Risk Evaluation of Selective Renal Arterial Embolization in the Treatment of Delayed Hemorrhage from Renal Artery Pseudoaneurysm After Partial Nephrectomy

Renal-artery pseudoaneurysm (RAP) is a well-described complication of partial nephrectomy. We aimed to evaluate the occurrence rate of delayed hemorrhage from RAP after partial nephrectomy, and to investigate the efficacy and safety of selective renal arterial embolization. Between January 2000 and December 2010, 426 partial nephrectomies were performed at our institution for treatment of small renal mass (SRMs). A retrospective review of these cases revealed that 14 patients developed a postoperative RAP (3.29 % incidence). We compared the clinical characteristics between the 14 patients with delayed renal hemorrhage and other 412 patients. RAP was diagnosed by renal angiography in 12 patients with delayed renal hemorrhage. Of the 12 patients, 10 patients were successfully treated with selective renal arterial embolization after presenting with symptoms postoperatively, 1 patient was treated with open surgery, and 1 patient was treated with nephrectomy. The other two patients showed no abnormalities in renal angiography, and the symptoms relieved by transfusion and hemostasis treatment. We found that tumor type, tumor size, tumor location, and surgical approach were significantly different between the 14 patients and other 412 patients. RAP showed a low incidence. The risk factors of RAP included renal cell carcinoma, tumor with large size, and tumor location. Most patients with delayed renal hemorrhage from RAP were successfully cured by selective renal arterial embolization. Therefore, selective renal arterial embolization can be used as the preferential therapy for RAP.     

Pathophysiological Responses in Rat and Mouse Models of Radiation-Induced Brain Injury

The brain is the major dose-limiting organ in patients undergoing radiotherapy for assorted conditions. Radiation-induced brain injury is common and mainly occurs in patients receiving radiotherapy for malignant head and neck tumors, arteriovenous malformations, or lung cancer-derived brain metastases. Nevertheless, the underlying mechanisms of radiation-induced brain injury are largely unknown. Although many treatment strategies are employed for affected individuals, the effects remain suboptimal. Accordingly, animal models are extremely important for elucidating pathogenic radiation-associated mechanisms and for developing more efficacious therapies. So far, models employing various animal species with different radiation dosages and fractions have been introduced to investigate the prevention, mechanisms, early detection, and management of radiation-induced brain injury. However, these models all have limitations, and none are widely accepted. This review summarizes the animal models currently set forth for studies of radiation-induced brain injury, especially rat and mouse, as well as radiation dosages, dose fractionation, and secondary pathophysiological responses.     

Hemorrhage associated with hepatic artery pseudoaneurysms after regional chemotherapy with floxuridine: case report

Pseudoaneurysms of the hepatic artery are a rare complication in patients with primary or secondary liver tumors treated with intra-arterial chemotherapy. We present two patients who developed this complication after placement of a catheter system into the gastroduodenal artery and initiation of regional chemotherapy with floxuridine. Diagnosis was made after symptomatic bleeding occurred, necessitating emergency angiography with coil embolization. Pseudoaneurysms usually occur after mechanical damage of the vessel wall, but the chemical toxicity of floxuridine may add to the development of vascular impairment.     

介入栓塞治疗脑动静脉畸形中造影技术的探讨

目的：通过对不同类型脑动静脉畸形（AVMB）造影技术的总结,分析AVMB的诊断及栓塞过程中选择性造影和微量造影应注意的技术问题。方法：人为地将50例AVMB分成两种类型,即高流低阻型（A）和高流高阻型（B）。根据不同的类型,设定不同的造影条件。栓塞过程中微量造影时。根据微导管的类型及微导管位于畸形团内的深度,定微量造影条件。结果：当微导管位于畸形团内时,压力应相应减低至120-150PSI,当微导管在供血动脉行经较长时,应重复造影,获得较为清晰的图像。结论：良好的造影条件能提供重要的影像信息,特别是微量造影,有时可能出现全和无的信息反差。     

Vascular malformations

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Understand the nomenclature and classification system of vascular malformations. 2. Evaluate these patients diagnostically. 3. Outline the surgical and nonsurgical options for treating these lesions. SUMMARY: Vascular anomalies can be classified into two unique groups-hemangiomas and vascular malformations-based on their endothelial properties. The present review focuses on vascular malformations rather than hemangiomas. The authors address capillary malformations, lymphatic malformations, venous malformations, and arteriovenous malformations. Diagnostic and therapeutic modalities are discussed with relevant case examples. A MEDLINE search was performed to gather all pertinent references. The physician treating these challenging lesions should ideally use a multidisciplinary team-based approach with multispecialty experience in diagnostic and therapeutic modalities for the management of vascular malformations.     

64排CT血管造影在脑动静脉畸形诊断中的价值

目的：探讨64排CT血管造影（computedtomography angiographycTA）对脑动静脉畸形（cerebral arefiovenousmalformation,AVM）的诊断价值。方法：16例AVM患者,均行64排螺旋CT血管造影检查,使用多种重建方法,由两名有经验的医生对畸形血管团进行分析。结果：16例均为单发瘤巢,16例AVM均显示了大小不等的畸形血管团及供血动脉和引流静脉,其中,2例同时伴脑出血（12．5％）,3例有出血后软化灶形成（18．75％）,16例发现有供血动脉31支,16例发现有明确的引流静脉21支。结论：64排CTA安全．快速．结合多种重建方法．可以清晰显示AVM的供血动脉、瘤巢．引流静脉．为临床治疗提供了可靠的信息．     

老年蛛网膜下腔出血的治疗方法和预后分析

目的:探讨70岁以上老年蛛网膜下腔出血患者的治疗方法和预后。方法:回顾性分析我院2006-2012年收治的49例老年蛛网膜下腔出血患者的临床资料及其预后。结果:49例患者入院时Hunt-Hess分级:Ⅰ级14例,Ⅱ级8例,Ⅲ级6例,Ⅳ级6例,Ⅴ级15例,其中14例采用开颅动脉瘤夹闭术,10例采用血管内介入栓塞术,25例采用内科保守治疗。治疗后6月,根据ADL量表评价预后(ADL≥60分为预后良好):内科保守治疗者仅3例预后良好,手术及栓塞术者17例预后良好。结论:对于老年蛛网膜下腔出血患者而言,影响患者预后的原因主要是出血导致的脑损伤和症状性脑血管痉挛,通过手术或栓塞术积极治疗破裂动脉瘤是预后良好的重要因素。