Paediatric intracranial dural arteriovenous fistulas: clinical characteristics, treatment outcomes and prognosis.

BACKGROUND: Compared with dural arteriovenous fistulas (DAVFs) in adult, paediatric DAVFs are notable for distinct clinical manifestations, low cure rate and poor prognosis. However, due to the limitations of small sample sizes, the long-term prognosis and follow-up data have not been described. METHODS: Clinical data from 43 consecutive paediatric DAVFs were documented and analysed between 2002 and 2022 at the author's institution. They were divided into infantile (Lasjaunias classification) and non-infantile (adult type and dural sinus malformation (DSM)) type DAVFs based on prognosis differences. RESULTS: Their mean age at first symptoms was 8.4±6.0 years. 29 boys and 14 girls presented between at birth and 18 years of age. 5 of 10 patients ≤1 year of age presented with asymptomatic cardiomegaly compared with 5/33 patients >1 year of age (p=0.022). 42 (88.4%) patients received endovascular treatment alone, while 9.3% underwent radiosurgery, burr hole embolisation or surgery. 28 (65.1%) patients experienced DAVF obliteration by the end of treatment. Among them, 26 cases underwent embolisation alone, one case had embolisation in conjunction with surgery, and one case underwent burr hole embolisation. The overall complication rate among patients was 9.3%, all resulting from endovascular treatment. According to the Lasjaunias Classification, there were 18 cases of adult type, 17 cases of infantile type and 8 cases of DSM. Compared with non-infantile-type DAVFs, infantile-type DAVFs showed more times of treatment, lower cure rate and worse prognosis (p<0.001, 0.003 and 0.021, respectively). The average follow-up duration was 41.4±36.2 months (3-228 months). 8 (22.9%) patients died. CONCLUSIONS: Most adult-type DAVFs and DSMs can now be effectively treated with embolisation, resulting in good outcomes and prognosis. However, there are still challenges in treating infantile-type DAVFs, and the prognosis is frequently poor.

A Novel Rat Model of Venous Hypertensive Myelopathy Produced by Arteriovenous Bypass Plus Venous Stenosis.

BACKGROUND AND OBJECTIVES: Venous hypertensive myelopathy (VHM), mainly induced by the spinal dural arteriovenous fistula, is a congestive spinal cord injury that currently has no appropriate animal model available in preclinical research. METHODS: Sprague Dawley rats (280-320 g) were used. The rats were divided into 3 groups: (1) Group 1, which underwent renal artery-dorsal spinal venous bypass (AVB group); (2) Group 2, which underwent renal artery-dorsal spinal venous bypass and drainage vein stenosis (AVB/VS group); and (3) Control group, with T13 dorsal vein ligation. The success of the model was assessed using Doppler ultrasound and 7.0-T magnetic resonance imaging. Transmission electron microscopy, histochemistry, proteomics, and western blot analysis were used to evaluate ultrastructural, pathological, and molecular features in the spinal cord and cerebrospinal fluid (CSF). RESULTS: The success rate of the arteriovenous bypass was 100% at 5 days and 83% at 2 weeks. The locomotor assessment showed decreased lower extremity strength in the AVB/VS group (P = .0067), whereas unremarkable changes were found in the AVB and Control groups. Histochemical staining suggested a 2-fold expansion of the dorsal spinal vein in the AVB/VS group, which was lower than that in the AVB group (P < .05); however, the former displayed greater myelin and neuronal damage (P < .05) and slight dilatation of the central canal (P > .05). Proteomics analysis revealed that the complement and coagulation cascade pathways were upregulated in the CSF of AVB/VS rats, whereas the C3 level was elevated both in the CSF and bilateral spinal cord. Furthermore, overexpression of C3, ITGB2, and CD9 in the spinal cord was confirmed by immunoblotting. CONCLUSION: These findings suggest that the AVB/VS model can effectively mimic the clinical and molecular characteristics of VHM. Furthermore, they suggest that impaired deep intramedullary venous drainage is the key reason for the VHM.

Intraorbital Arteriovenous Fistulas: Case Series and Systematic Review.

BACKGROUND AND OBJECTIVES: Intraorbital arteriovenous fistulas (AVFs) are an extremely rare subtype of intracranial fistula with ophthalmic symptoms similar to cavernous sinus dural AVFs or carotid cavernous fistulas but worse visual outcomes. Here, we present a case series and thorough systematic review on intraorbital AVFs to demonstrate treatment modalities and address this rare type of AVF. METHODS: We conducted a retrospective study at a single center, in which we identified all cases of intraorbital AVFs that occurred between 2002 and 2022. We collected and analyzed data on demographics, fistula characteristics, treatment methods, clinical outcomes, and fistula closure. In addition, we conducted a systematic review of intraorbital AVFs. RESULTS: Seven cases in our center and 41 cases of intraorbital AVFs reported in the 35 articles were identified. At our center, transarterial embolization (TAE) (42.9%) alone resulted in immediate complete occlusion in 3 cases. Transvenous embolization (14.3%) resulted in one case of immediate complete occlusion. In 2 cases, surgery (28.6%) resulted in immediate complete occlusion. In one case, conservative treatment (14.3%) was used, and the fistula was eventually spontaneously occluded. Immediate complete occlusion rate was 85.7%. One blindness occurred (14.3%). In the literature reported, 3 cases (60%) of retinal artery occlusion were reported when performing TAE via the ophthalmic artery. Two fistulas recurred as reported. In 33 (80.5%) patients, the fistula was finally completely occluded. CONCLUSION: TAE via the ophthalmic artery carries a high risk of blindness and a low cure rate. Transvenous techniques such as conventional transvenous routes, surgical exposure, or direct puncture of the drainage vein have been used as the first line of treatment for intraorbital AVFs.

Isolated sinus dural arteriovenous fistulas: a single-center experience in 44 patients.

BACKGROUND: Isolated sinus dural arteriovenous fistulas (DAVFs) constitute a rare and distinctive subtype of DAVF, typically found in small case numbers or case reports. The optimal treatment for this DAVF type remains unclear. OBJECTIVE: This study aims to further detail the treatment outcomes of isolated sinus DAVFs in a sizable cohort from a single center. METHODS: A retrospective study was undertaken on a consecutive series of patients with isolated sinus DAVFs treated at a single institution from 2002 to 2022. The article delineates the clinical presentation, angiographic features, treatment strategy, clinical and angiographic outcomes, and complications. RESULTS: The cohort consisted of 31 males and 13 females, with an average age of 52.0 ± 15.5 years (range, 16-83). The success rate for trans-arterial embolization (TAE) was 97.3% (36/37). Transvenous embolization (TVE) with the reopening technique was successful in 3 of 4 patients (75.0%). Two open burr-hole TVE cases (66.7%, 2/3) and one surgery (100%) resulted in immediate complete closure of the fistula. Immediate complete occlusion was achieved in 93.2% (41/44) of cases. There was one major complication (2.3%, 1/44) and two fistulas recurred (9.5%, 2/21). CONCLUSIONS: The majority of isolated sinus DAVFs can be effectively treated with TAE using Onyx. TVE and surgery serve as alternative techniques when arterial access is deemed inappropriate or when complete occlusion cannot be attained with TAE. Complete embolization of isolated sinus DAVFs by TAE can typically be achieved without delay.

Middle cranial fossa non-cavernous sinus dural arteriovenous fistulas: 20 years of experience.

Non-cavernous sinus (CS) dural arteriovenous fistulas (DAVFs) involving the sphenoid bone are rare entities that are easily confused with one another due to the complex structure and high variability of the venous system around the middle cranial fossa. We present a large retrospective study on middle cranial fossa non-CS DAVFs and review the literature on DAVF treatment in this location as well as relative anatomy. 15 patients had DAVFs involving the lesser sphenoid wing and 11 patients had DAVFs involving the greater sphenoid wing. Six patients presented with intracranial hemorrhage or subarachnoid hemorrhage (23.1%, 6/26). The most common symptoms were eye symptoms (38.5%, 10/26). Nineteen patients were treated with trans-arterial embolization (TAE) using liquid embolic agents and two patients were treated with transvenous embolization (TVE) using Onyx or in combination with coils. Surgical disconnection of the drainage veins was performed in five patients, with three cases experiencing unsuccessful TAE. Anatomic cure was achieved in 92.3% of the patients (24/26). Twelve patients had DSA and clinical follow-up from 3 to 27 months. There was one recurrence (8.3%) of the fistula in the patient two months after the initial complete occlusion. The majority of patients can be cured endovascularly. Laterocavernous sinus DAVFs may not be embolized by transvenous approach via the cavernous sinus because there is often no connection between them in most patients. A small percentage of patients may require surgical ligation to be cured.

Intraoperative direct venous puncture and embolization for arteriovenous shunt below the conus medullaris: a prospective cohort study.

BACKGROUND: Arteriovenous shunt below the conus medullaris (AVS-BC) is easily misdiagnosed and mistreated due to its rarity. Achieving an anatomical cure solely through endovascular or surgical means is challenging. This study aimed to summarize the clinical and radiological features of AVS-BC and evaluate the safety and efficacy of hybrid techniques represented by intraoperative direct venous puncture and embolization (IVPE). METHODS: The patients with AVS-BC were grouped into those with dural, intradural, and paravertebral shunts. The patients undergoing hybrid procedures were consecutively recruited between August 2016 and July 2022. The modified Aminoff and Logue's Scale (mALS) and the modified Denis Pain and Numbness Scale (mDS) were used to evaluate motor and sensation disturbances. RESULTS: A total of 42 patients (35 males, 83.3%) were included with an average age of 57.38±10.79 years. Most patients presented with lower limb weakness and sphincter disturbances. Their preoperative average mALS score was 7.17±2.61 and the preoperative average mDS score was 3.88±1.76. There were 28 patients (66.7%) who received IVPE. The mean clinical follow-up reached 41.30±21.10 months. All patients achieved anatomical cures without permanent neurological complications. It showed a significant improvement in mALS scores after the intervention in the spinal dural arteriovenous fistula only (P=0.026). No recurrences were reported. CONCLUSIONS: Differentiating AVS-BC mainly relied on identifying supplying arteries, shunt placements, and draining veins. The hybrid technique typified by IVPE conferred a safe anatomical cure for AVS-BC.

Role of optical coherence tomography in pipeline embolization device for the treatment of vertebral-basilar artery dissecting aneurysms.

BACKGROUND: Vertebral-basilar artery dissecting aneurysms (VADAs) are an uncommon phenomenon in all fields of cerebrovascular disease. The flow diverter (FD) can be used as an endoluminal reconstruction device that promotes neointima formation at the aneurysmal neck and preserves the parent artery. To date, imaging examinations such as CT angiography, MR angiography, and DSA are the main methods used to evaluate the vasculature of patients. However, none of these imaging methods can reveal the situation of neointima formation, which is of great importance in evaluating occlusion of VADAs, especially those treated with a FD. METHODS: Three patients were included in the study from August 2018 to January 2019. All patients underwent preprocedural, postprocedural, and follow-up evaluations with high resolution MRI, DSA, and optical coherence tomography (OCT), as well as the formation of intima on the surface of the scaffold at the 6 month follow-up. RESULTS: Preprocedural, postoperative, and follow-up high resolution MRI, DSA, and OCT of all three cases successfully evaluated occlusion of the VADAs and occurrence of in stent stenosis from different views of intravascular angiography and neointima formation. CONCLUSIONS: OCT was feasible and useful to further evaluate VADAs treated with FD from a near pathological perspective, which may contribute toward guiding the duration of antiplatelet medication and early intervention of in stent stenosis.

Clinical features, treatment strategies and outcomes of craniocervical junction arteriovenous fistulas: a cohort study of 193 patients.

BACKGROUND: Craniocervical junction (CCJ) arteriovenous fistulas (AVFs) are rare. The current treatment strategies for AVFs with different angioarchitecture need to be clarified. The present study aimed to analyse the correlation between angioarchitecture and clinical characteristics, share our experience in treating this disease and identify risk factors associated with subarachnoid haemorrhage (SAH) and poor outcomes. METHODS: A total of 198 consecutive patients with CCJ AVFs from our neurosurgical centre were retrospectively reviewed. The patients were grouped according to their clinical manifestations, and their baseline clinical characteristics, angioarchitecture, treatment strategies and outcomes were summarised. RESULTS: The patients' median age was 56 years (IQR 47-62 years). The majority of patients were men with 166 (83.8%) patients. The most common clinical manifestation was SAH (52.0%), followed by venous hypertensive myelopathy (VHM) (45.5%). The most common CCJ AVFs type was dural AVF, with 132 (63.5%) fistulas. The most frequent fistula location was C-1 (68.7%) and dural branch of vertebral artery (70.2%) was the most involved arterial feeders for fistulas. The most common direction of venous drainage was descending intradural drainage (40.9%), followed by ascending intradural drainage (36.5%). Microsurgery was the most common treatment strategy applied for 151 (76.3%) patients, 15 (7.6%) patients were treated with interventional embolisation only, and 27 (13.6%) received both interventional embolisation and microsurgical treatment. The learning curve for microsurgery only was analysed by cumulative summation method, and the turning point was the 70th case, and blood loss in post-group was lower than that in pre-group (p=0.034). At the last follow-up, there were 155 (78.3%) patients with favourable outcomes (modified Rankin Scale(mRS)<3). Age≥56 (OR 2.038, 95% CI 1.039 to 3.998, p=0.038), VHM as the clinical manifestation (OR 4.102, 95% CI 2.108 to 7.982, p<0.001) and pretreatment mRS≥3 (OR 3.127, 95% CI 1.617 to 6.047, p<0.001) were significantly associated with poor outcomes. CONCLUSION: The arterial feeders and direction of the venous drainage were important factors in the clinical presentations. The location of fistula and drainage vein was essential for choosing different treatment strategies. Older age, VHM onset and poor pretreatment functional status predicted poor outcomes.

An Intraosseous Pterygopalatine Fossa Dural Arteriovenous Fistula.

Intraosseous dural arteriovenous fistulas (DAVFs) are distinct in that the fistula is located within the bone rather than the dura through which the dural vessels pass. It has been stated that only fistulas within marrow should be considered as intraosseous DAVFs rather than DAVFs with traditional angioarchitecture that erode into bone or are located within a bony foramen. The ambiguity in the definition may have contributed to the oversight and scarcity of relevant cases reported in the literature. Three- or four-dimensional digital subtraction angiography is useful for determining the location of the fistula and developing treatment plans. We present an intraosseous DAVF around the pterygopalatine fossa using a transvenous approach.

Magnetic Fe-doped silicon carbide induced microwave activated persulfate for decabromodiphenyl ether removal: Mechanism and unique degradation pathway.

In this work, the magnetic nanocomposite Fe@SiC was prepared by a hydrothermal method and determined by SEM, XRD, XPS, FTIR and VNA. Fe3O4 particles were loaded onto SiC with great success, and the synthesized composites had favorable microwave absorption properties. Fe@SiC was used to activate persulfate in a microwave field for the degradation of BDE209 in soil. Specifically, the synergistic interaction between microwaves and Fe@SiC showed excellent catalytic performance in activating PS to degrade BDE209 (90.1% BDE209 degradation in 15 min). The presence of •OH, O2•- and 1O2 was demonstrated based on quench trapping and EPR experiments. LC‒MS was applied to determine the intermediates and propose the possible degradation pathway for BDE209 in the MW/Fe@SiC/PS system, and it was found that BDE209 produced almost no lower brominated diphenyl ethers. Therefore, the toxicity of BDE209 was found to be reduced using toxicity assessment software. Overall, this work provides an effective approach for the degradation of BDE209 in environmental remediation.

An isolated Sinus Intracranial Dural Arteriovenous Fistula with Unusual Drainage Pattern.

Isolated sinus dural arteriovenous fistulas (DAVFs) involve a dural sinus with occlusion on both sides of the diseased sinus segment. Because of venous drainage refluxing from the isolated sinus into the cortical veins, all isolated sinus DAVFs are Borden type III or Cognard type Ⅲ/Ⅳ. Venous drainage typically involves temporo-occipital cortical veins or the superior petrosal sinus and tributaries of the petrosal vein. However, drainage veins involving the perimedullary venous system are extremely rare. Here, we present a case of Cognard type V isolated sinus DAVF successfully treated with balloon catheter and Onyx.

Surgical timing and long-term outcomes in patients with severe haemorrhagic spinal cord cavernous malformations.

BACKGROUND: Surgical resection of the lesions remains the main treatment method for most symptomatic spinal cord cavernous malformations (SCCMs) to eliminate the occupation and associated subsequent lifelong haemorrhagic risk. However, the timing of surgical intervention remains controversial, especially for patients in the acute stage after severe haemorrhage. METHODS: Patients diagnosed with SCCMs who were surgically treated between January 2002 and December 2021 were selected and retrospectively reviewed. The Modified McCormick Scale (MMS) was used to evaluate neurological and disability status. All medical information was reviewed, and all patients were followed up for at least 6 months. RESULTS: A total of 279 patients were ultimately included. With regard to long-term outcomes, 110 (39.4%) patients improved, 159 (57.0%) remained unchanged and 10 (3.6%) worsened. For patients with an MMS score of 2-5 on admission, in univariate and multivariate analyses, a ≤6 weeks period between onset and surgery (adjusted OR 3.211, 95% CI 1.504 to 6.856, p=0.003) was a significant predictor of improved MMS. Among 69 patients who first presented with severe haemorrhage, undergoing surgery within 6 weeks of the onset of severe haemorrhage (adjusted OR 4.901, 95% CI 1.126 to 21.325, p=0.034) was significantly associated with improvement of MMS score. CONCLUSION: Surgical timing can influence the long-term outcome of SCCMs. For patients with symptomatic SCCMs, especially those with severe haemorrhage, early surgical intervention within 6 weeks can provide more benefit.

Clinical features, treatment, and outcomes of cavernous sinus dural arteriovenous fistulas: a cohort study of 141 patients.

PURPOSE: The cavernous sinus (CS) region is a common region of dural arteriovenous fistula (DAVF). Over time, treatment strategies are gradually changing. In this study, we present our center's experience in managing CS-DAVF over the past 20 years. METHODS: Medical records of patients diagnosed with CS-DAVF between 2002 and 2021 were collected for analysis. Patients meeting the predefined inclusion and exclusion criteria were included. This study summarized and analyzed their clinical characteristics, CS-DAVF angioarchitecture, treatment strategies, and outcomes. RESULTS: A total of 141 patients (mean age 55 years, 46 males) were included in this study. Ocular/orbital symptoms were the most frequently reported initial symptoms, with 84 (59.6%) patients experiencing these symptoms first. Presentation with ocular/orbital symptoms as the first symptom was associated with thrombosis of the inferior petrosal sinus (p = 0.032). Presentation with headache/dizziness and tinnitus/intracranial murmur as the first symptom was associated with sphenoparietal sinus/superficial middle cerebral vein drainage (p = 0.011). Among the patients, 131 (92.9%) patients received endovascular treatment, with 114 (87.0%) undergoing transvenous embolization. Onyx (92.4%) and coil (74.8%) were the most used embolic materials. 17 (13.0%) of the patients who received endovascular treatment suffered intraoperative or postoperative complications, and 11 (64.7%) patients fully recovered within 6 months after discharge. CONCLUSION: Ocular/orbital symptoms were the most common first symptom of CS-DAVF. The mode of venous drainage played a significant role in determining the first symptoms. Transvenous embolization using Onyx or a combination of Onyx and coils was the primary treatment modality.

Evolutionary neural architecture search combining multi-branch ConvNet and improved transformer.

Deep convolutional neural networks (CNNs) have achieved promising performance in the field of deep learning, but the manual design turns out to be very difficult due to the increasingly complex topologies of CNNs. Recently, neural architecture search (NAS) methods have been proposed to automatically design network architectures, which are superior to handcrafted counterparts. Unfortunately, most current NAS methods suffer from either highly computational complexity of generated architectures or limitations in the flexibility of architecture design. To address above issues, this article proposes an evolutionary neural architecture search (ENAS) method based on improved Transformer and multi-branch ConvNet. The multi-branch block enriches the feature space and enhances the representational capacity of a network by combining paths with different complexities. Since convolution is inherently a local operation, a simple yet powerful "batch-free normalization Transformer Block" (BFNTBlock) is proposed to leverage both local information and long-range feature dependencies. In particular, the design of batch-free normalization (BFN) and batch normalization (BN) mixed in the BFNTBlock blocks the accumulation of estimation shift ascribe to the stack of BN, which has favorable effects for performance improvement. The proposed method achieves remarkable accuracies, 97.24 [Formula: see text] and 80.06 [Formula: see text] on CIFAR10 and CIFAR100, respectively, with high computational efficiency, i.e. only 1.46 and 1.53 GPU days. To validate the universality of our method in application scenarios, the proposed algorithm is verified on two real-world applications, including the GTSRB and NEU-CLS dataset, and achieves a better performance than common methods.