Angioarchitecture Classification and Treatment Modalities of Craniocervical Junction Arteriovenous Fistulas: A Cohort Study of 155 Patients.

BACKGROUND AND OBJECTIVES: Craniocervical junction (CCJ) arteriovenous fistulas (AVFs) are rare. Variability in clinical manifestations and treatment strategies for CCJ AVFs stems from differences in their angioarchitecture. Our study aims to categorize CCJ AVFs based on their angioarchitecture and explore the associated clinical features and treatment modalities for distinct CCJ AVF types. METHODS: The authors conducted a retrospective analysis of patients with CCJ AVFs treated at a single neurosurgical facility over the past decade. These patients were classified based on the angioarchitecture of their CCJ AVFs. The analysis included an evaluation of angioarchitecture, clinical characteristics, treatment strategies, and outcomes. RESULTS: The study included 155 patients, with a median age of 56 years, collectively manifesting 165 CCJ AVFs. Our classification identified 4 distinct CCJ AVF types: epidural AVFs (19 [11.5%]), dural AVFs (98 [59.4%]), radicular AVFs (33 [20.0%]), and perimedullary AVFs (15 [9.1%]). Further differentiation was applied based on the presence of pial feeders. The predominant fistula location was at cervical-1 (77.0%). Ascending intradural drainage (52.7%) and descending intradural drainage (52.1%) were frequently observed drainage patterns. Patients with dural AVF predominantly presented with venous hypertensive myelopathy, whereas patients with other types of CCJ AVFs showed a higher incidence of subarachnoid hemorrhage (P = .012). Microsurgery was the predominant treatment, applied in the management of 126 (76.4%) AVFs, whereas 8 (4.8%) AVFs exclusively underwent interventional embolization and 25 (15.2%) received a combination of interventional embolization and microsurgical treatment. CONCLUSION: CCJ AVFs can be distinguished based on the fistula location and the arterial feeders. Currently, microsurgery stands as the preferred treatment strategy for CCJ AVFs, whereas interventional embolization plays a distinctive role in cases with specific angioarchitecture or as a pretreatment measure before microsurgery.

Microsurgical treatment for superior petrosal sinus dural arteriovenous fistulas.

Superior petrosal sinus (SPS) dural arteriovenous fistulas (DAVFs) are a commonly encountered type of tentorial DAVF that occasionally requires microsurgical intervention. This study aims to analyze the tributaries of the superior petrosal vein (SPV) observed intraoperatively, their association with clinical symptoms, and venous drainage patterns. This retrospective study reviewed 34 consecutive patients with SPS DAVFs who underwent microsurgical treatment at a single institution between 2014 and 2022. The cohort had a mean age of 52.8 ± 11.8 years, with 85.3% (29/34) being male. Predominant symptoms included venous hypertensive myelopathy (VHM) (55.9%) and intraparenchymal or subarachnoid hemorrhage (23.5%). Standard retrosigmoid approach was used to ligate 94.1% (32/34) of the lesions, resulting in immediate complete fistula occlusion for all patients. Supratentorial venous drainage patterns were associated with a higher incidence of intracranial hemorrhage and venous varix (P = 0.047). Infratentorial drainage patterns were more frequently linked with VHM-related symptoms (P<0.001). Patients presenting VHM-related symptoms showed a higher prevalence of drainage through the vein of the cerebellopontine fissure (VCPF) (P = 0.01), while those with intracranial hemorrhage symptoms exhibited a higher prevalence of pontotrigeminal vein (PTV) drainage (P = 0.033) in their DAVFs. Endovascular management of SPS DAVFs carries inherent risks. Surgical treatment via standard retrosigmoid craniotomy offers favorable clinical outcomes with high rates of cure. In cases featuring infratentorial venous drainage, the predominant arterialized tributary of the SPV was the VCPF, commonly associated with VHM-related symptoms. Conversely, in cases with supratentorial venous drainage, the predominant arterialized SPV tributary was the PTV, often associated with intracranial hemorrhage symptoms.

Dural arteriovenous fistulas in the falx cerebri: case series and literature review.

Dural arteriovenous fistulas (DAVFs) within the falx cerebri are infrequently documented and may be linked with the falcine sinus/venous plexus. The falcine sinus/venous plexus, often regarded as a normal venous structure, can exhibit pathological characteristics, differing from the persistent fetal falcine sinus. A retrospective analysis was conducted at a single center to identify all cases of DAVFs within the falx cerebri spanning from 2002 to 2022. Demographic data, fistula features, treatment modalities, clinical outcomes, and fistula closure were collected and analyzed. Additionally, relevant literature on DAVFs in this location was reviewed. Ten cases were identified at our center, supplemented by 13 cases reported in the literature. In our cohort, patients had an average age of 49.4 ± 8.1 years, with a male predominance of 90%. Trans-arterial embolization (TAE) alone achieved immediate complete occlusion in eight cases, while conservative treatment was pursued in two cases. No treatment-related complications or fistula recurrences were observed. In the literature, seven patients underwent direct surgery, three underwent TAE, and one underwent both direct surgery and radiosurgery for complete fistula closure. No instances of fistula recurrence or treatment complications were reported. Dural arteriovenous fistulas within the falx cerebri are rare, with limited literature available. They typically present as aggressive lesions. Treatment options include direct surgery or TAE. However, due to a lack of long-term DSA follow-up, the cure and recurrence rates are unknown for endovasdcular therapy. Further investigation is warranted to elucidate the involvement of the falcine sinus/venous plexus in falx cerebri DAVFs.

The natural course, treatment outcomes, and long-term prognosis of cervical spinal cord arteriovenous shunts.

OBJECTIVE: The highly intricate nature of the cervical spinal cord can cause arteriovenous shunts in these segments that may be associated with heightened clinical risks and treatment complexities. In this article, the authors aimed to provide a comprehensive analysis of the detailed natural course, treatment, and clinical outcomes of cervical spinal cord arteriovenous shunts (SCAVSs) based on the largest cohort to date. METHODS: Two hundred forty consecutive patients were included. Data on clinical presentation, angioarchitecture, treatment, and follow-up were retrospectively reviewed. RESULTS: The cohort demonstrated a greater prevalence of acute onset (63.3% vs 36.7%). Spontaneous recovery was observed in 63.7% of patients after onset, with a significantly elevated recovery rate observed among patients experiencing acute onset (72.4% vs 48.9%, p < 0.001). The risks of acute and gradual clinical deterioration after onset was 11.9%/year and 13.4%/year, respectively. Microsurgery was performed in 39.6% of patients, while the remaining 60.4% exclusively underwent embolization. The complete obliteration rate was 65.3% after microsurgery and 21.4% after embolization. The rate of treatment-related deterioration was 14.7% after microsurgery and 6.2% after embolization. After partial treatment, the acute and gradual deterioration rates were 4.1%/year and 6.6%/year, respectively. Lack of spontaneous recovery after onset was an independent predictor of embolization-related deterioration (OR 17.905, p = 0.007) and long-term gradual deterioration after partial treatment (HR 2.325, p = 0.021). After a median follow-up period of 32.55 months, prognosis was unfavorable in 16.7% of patients, with the sole independent risk factor being the absence of spontaneous recovery after onset (OR 2.476, p = 0.018). CONCLUSIONS: The outcomes of patients with cervical SCAVS were generally favorable, even in patients with only partial obliteration of the lesions. However, patients who did not show a trend toward spontaneous recovery after onset had a significantly elevated risk of unfavorable prognosis, highlighting the need for prompt clinical intervention.

Isolated spinal artery aneurysm: etiology, clinical characteristics, and outcomes.

OBJECTIVE: Isolated spinal aneurysms (ISAs) are rare causes of subarachnoid hemorrhage (SAH), which encompass a highly heterogeneous group of clinical entities with multifarious pathogeneses, clinical characteristics, and treatment strategies. Therefore, knowledge about the ISAs remains inadequate. In this study, the authors present a comprehensive analysis of clinical data associated with ISAs at their institutions to enhance the understanding of this disease. METHODS: Patients with ISAs confirmed by spinal angiography or surgery at the authors' institutions between 2015 and 2022 were included. Data regarding clinical presentation, lesion location, aneurysm morphology, comorbidities, treatment results, and clinical outcomes were reviewed. RESULTS: Seven patients with ISAs were included in the study. Among them, 4 patients (57.1%) experienced severe headache, and 3 patients (42.9%) reported sudden-onset back pain. Additionally, lower-extremity weakness and urinary retention were observed in 2 of these patients (28.6%). Four of the aneurysms exhibited fusiform morphology, whereas the remaining were saccular. All saccular aneurysms in this series were attributed to hemodynamic factors. Conservative treatment was administered to 3 patients, 2 of whom underwent follow-up digital subtraction angiography, which showed spontaneous occlusion of both aneurysms. Four patients ultimately underwent invasive treatments, including 2 who underwent microsurgery and 2 who received endovascular embolization. One patient died of recurrent SAH, while the remaining 6 patients had a favorable prognosis at the latest follow-up assessment. CONCLUSIONS: The morphology of aneurysms may be associated with their etiology. Saccular ISAs are usually caused by pressure due to abnormally increased blood flow, whereas fusiform lesions may be more likely to be secondary to vessel wall damage. The authors found that a saccular spinal aneurysm in young patients with a significant dilated parent artery may be a vestige of spinal cord arteriovenous shunts. ISAs can be managed by surgical, endovascular, or conservative procedures, and the clinical outcome is generally favorable. However, the heterogeneous nature of the disease necessitates personalized treatment decision-making based on specific clinical features of each patient.

Safety and efficacy of dual antiplatelet drugs for stent-assisted embolization on risk of stroke and prognosis in patients with ruptured intracranial aneurysms: One center results of CIAP-5 clinical trial.

BACKGROUND: Although stent-assisted coiling embolization (SAC) has been associated with a higher risk of ischemic and hemorrhagic complications, the use of SAC continues to rise for treating ruptured intracranial aneurysms (RIAs). This study aims to assess the safety and effectiveness of dual antiplatelet therapy (DAPT) in the context of RIAs. METHODS: We conducted a retrospective analysis at a single center, involving patients with aneurysmal subarachnoid hemorrhage (aSAH) between May 1, 2017 and December 31, 2021. Patients were categorized into two groups: the SAC group and the non-SAC (NSC) group. Patients in the SAC group received DAPT. We compared modified Rankin Scale (mRS) score, along with hemorrhagic and ischemic complications, between the two groups to evaluate the safety and efficacy of DAPT for SAC. RESULTS: The study included a total of 541 patients, of whom 38 (7.0%) experienced hemorrhagic complications and 48 (8.9%) developed ischemic complications. Additionally, 99 (18.3%) and 84 (15.5%) had poor clinical outcomes at discharge and 6 months, respectively. However, no statistically significant differences were observed between the two groups. Our analysis revealed that aneurysm location in the posterior circulation was a significant risk factor for an unfavorable prognosis when antiplatelet drugs were used following SAC (p = 0.025). CONCLUSIONS: Administering antiplatelet drugs after SAC for RIAs has demonstrated both safety and effectiveness. However, caution should be exercised when considering this treatment strategy for RIAs located in the posterior circulation due to the potentially elevated risk.

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.

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.

Syringomyelia secondary to thoracic spinal dural arteriovenous fistula presenting as paraparesis.

Spinal dural arteriovenous fistula (SDAVF) is also known as a type 1 spinal arteriovenous malformation, representing the most frequent vascular malformation of the spine. A high suspicion index is often required for the initial diagnosis of SDAVF because of subtle magnetic resonance imaging signs. We present the case of a patient with SDAVF associated with syringomyelia of the thoracic spinal cord and hypothesize that a fistula might induce intramedullary fluid accumulation due to venous hypertension, which leads to syrinx formation.

Maxillary Nerve as Landmark for Exposure of the Internal Maxillary Artery in Extracranial-Intracranial Bypass Surgery.

OBJECTIVE: To establish a new method for fast exposure of the internal maxillary artery (IMA) during extracranial-intracranial bypass surgery. METHODS: To explore the positional relationship between the IMA and the maxillary nerve and pterygomaxillary fissure, 11 formalin-fixed cadaveric specimens were dissected. Three bone windows of the middle fossa were created for further analysis. Then the IMA length that could be pulled up above the middle fossa was measured after different degrees of removal of bony structure. The IMA branches under each bone window were also explored in detail. RESULTS: The top of the pterygomaxillary fissure was located 11.50 mm anterolateral to the foramen rotundum. The IMA could be identified just inferior to the infratemporal segment maxillary nerve in all specimens. After drilling of the first bone window, the IMA length that could be pulled above the middle fossa bone was 6.85 mm. After drilling of the second bone window and further mobilization, the IMA length that could be harvested was significantly longer (9.04 mm vs. 6.85 mm; P < 0.001). Removal of the third bone window did not significantly improve the IMA length that could be harvested. CONCLUSIONS: The maxillary nerve could be used as a reliable landmark for the exposure of the IMA in the pterygopalatine fossa. With our technique, the IMA could be easily exposed and sufficiently dissected without zygomatic osteotomy and extensive middle fossa floor removal.

Clinical and prognostic features of venous hypertensive myelopathy from craniocervical arteriovenous fistulas: a retrospective cohort study.

OBJECTIVE: Current knowledge about venous hypertensive myelopathy (VHM) is incomplete. This study was performed with the aim of clarifying the clinical features and outcomes of craniocervical VHM. METHODS: This retrospective, single-center cohort study included 65 patients with craniocervical junction arteriovenous fistulas resulting in VHM treated in Xuanwu Hospital from January 1, 2002, to December 30, 2020. All patients underwent microsurgery or endovascular treatment. The primary outcome was neurological function assessment using the Japanese Orthopaedic Association (JOA) scale, modified Aminoff-Logue Scale (mALS), and Venous Hypertensive Myelopathy Scale (VHMS). The secondary outcomes were recurrences and postoperative adverse events. Pearson linear regression and receiver operating characteristic curves were used to evaluate the relationships among the three scales. Kaplan-Meier and multivariate logistic regression analyses were performed to predict outcomes. RESULTS: The mean patient age was 57.4 ± 11.4 years, and 88% of patients were male. The 1-year follow-up rate was 83.1%, and the 5-year follow-up rate was 50.8%. The VHMS was correlated with the JOA (R2 = 0.6722) and mALS (R2 = 0.7399) and increased the assessment accuracy by approximately 20% when compared with the other two scales. Overall, 25.9% of patients experienced delayed neurological decline beyond the 1-year follow-up. Further logistic regression suggested that age > 65 years was an independent predictor (OR 7.831, 95% CI 1.090-56.266; p = 0.041). Embolic recanalization and new bilateral symmetry feeders were the major reasons for recurrence. Recurrence increased the risk of adverse events after the second surgery (OR 20.455, 95% CI 1.170-357.320; p = 0.039). CONCLUSIONS: CCJ AVFs resulting in VHM are a rare but deadly complication, and providers should be cautious of age-related delayed neurological decline and strive for a one-time anatomical cure.

Clinical features and outcomes of perimedullary arteriovenous fistulas: comparison between micro- and macro-type lesions.

BACKGROUND: Although the angioarchitecture of perimedullary arteriovenous fistulas (PMAVFs) is straightforward, their size and blood flow are highly heterogeneous. This study aimed to evaluate the differences in clinical features and outcomes of PMAVFs based on lesion size and blood flow. METHODS: 114 consecutive patients with PMAVFs from two institutes were retrospectively reviewed. The lesions were classified as either micro-PMAVFs (shunt point diameter <1 cm) or macro-PMAVFs (shunt point diameter ≥1 cm). RESULTS: The patients with micro-PMAVFs were older at the first presentation (33.50 vs 13.50 years, p<0.001). Macro-PMAVFs were more commonly associated with spinal metameric arteriovenous shunts (6.9% vs 28.6%, p=0.003). Compared with the macro-PMAVFs, the micro-PMAVFs showed a significantly higher risk of gradual clinical deterioration after initial onset (73.6%/year vs 10.0%/year; HR 3.888, 95% CI 1.802 to 8.390, p=0.001). A total of 58.6% of the micro-PMAVFs were treated surgically, whereas 85.7% of the macro-PMAVFs were treated via endovascular approaches. Complete obliteration was 73.7% for the whole cohort, and was more common for the micro-PMAVFs than for the macro-PMAVFs (87.9% vs 58.9%, p=0.001). At the last follow-up, spinal function was significantly improved compared with the pretreatment status, and the rate of severe disability of patients with macro-PMAVFs was slightly but not significantly higher than that of patients with micro-PMAVFs (16.1% vs 8.6%, p=0.315) CONCLUSIONS: The clinical risks, treatment strategies and obliteration rates of PMAVFs differ based on their size and blood flow.

Adult dural arteriovenous fistulas in Galen region: More to be rediscovered.

Background: Dural arteriovenous fistulas (DAVFs) in the Galen region are the most deeply located and most complex type of dural arteriovenous fistulas. However, cases of DAVFs in this region have not been well described. Thus, we aimed to summarize the characteristics of Galenic DAVFs involving clinical symptoms, anatomical architecture, and drainage patterns, providing experientially therapeutic strategies for these lesions based on our 20 years of clinical experience. Methods: We retrospectively examined 31 patients with Galenic DAVFs between January 2000 and June 2021. A comprehensive analysis was carried out based on the symptoms, imaging features, feeding arteries, draining veins, number and location of the fistulas, choice of treatment methods, and prognosis assessment. Results: Twenty-nine patients received endovascular embolization, and no perioperative deaths occurred. A transarterial approach was performed in 27 patients, and a combined transarterial and transvenous approach in one. And in one case, access was established by surgical drilling and embolization was done via the venous route. Twenty-four cases were completely obliterated after first embolization, and another five cases received a second period treatment. Only one patient developed cognitive dysfunction after embolization, and the outcomes of the remaining patients were improved at long-term follow-up. Conclusion: The understanding of symptoms of non-hemorrhagic neurological deficits in DAVF needs to be further clarified. Lesions with pial feeders may be considered first when determining surgical orders. Multi-approach and multi-stage embolization would be safe and effective. Excessive embolization and deep-vein system obstruction should be avoided. Approach creation by surgery would be an innovative interventional therapy.

Gene identification and tissue expression analysis inform the floral organization and color in the basal angiosperm Magnolia polytepala (Magnoliaceae).

MAIN CONCLUSION: In Magnolia polytepala, the formation of floral organization and color was attributed to tissue-dependent differential expression levels of MADS-box genes and anthocyanin biosynthetic genes. In angiosperms, the diversity of floral morphology and organization suggests its value in exploring plant evolution. Magnolia polytepala, an endemic basal angiosperm species in China, possesses three green sepal-like tepals in the outermost whorl and pink petal-like tepals in the inner three whorls, forming unique floral morphology and organization. However, we know little about its underlying molecular regulatory mechanism. Here, we first reported the full-length transcriptome of M. polytepala using PacBio sequencing. A total of 16 MADS-box transcripts were obtained from the transcriptome data, including floral homeotic genes (e.g., MpAPETALA3) and other non-floral homeotic genes (MpAGL6, etc.). Phylogenetic analysis and spatial expression pattern reflected their putative biological function as their homologues in Arabidopsis. In addition, nine structural genes involved in anthocyanin biosynthesis pathway had been screened out, and tepal color difference was significantly associated with their tissue-dependent differential expression levels. This study provides a relatively comprehensive investigation of the MADS-box family and anthocyanin biosynthetic genes in M. polytepala, and will facilitate our understanding of the regulatory mechanism underlying floral organization and color in basal angiosperms.

From Floral Induction to Blooming: The Molecular Mysteries of Flowering in Woody Plants.

Flowering is a pivotal developmental process in response to the environment and determines the start of a new life cycle in plants. Woody plants usually possess a long juvenile nonflowering phase followed by an adult phase with repeated flowering cycles. The molecular mechanism underlying flowering regulation in woody plants is believed to be much more complex than that in annual herbs. In this review, we briefly describe the successive but distinct flowering processes in perennial trees, namely the vegetative phase change, the floral transition, floral organogenesis, and final blooming, and summarize in detail the most recent advances in understanding how woody plants regulate flowering through dynamic gene expression. Notably, the florigen gene FLOWERING LOCUS T(FT) and its antagonistic gene TERMINAL FLOWER 1 (TFL1) seem to play a central role in various flowering transition events. Flower development in different taxa requires interactions between floral homeotic genes together with AGL6 conferring floral organ identity. Finally, we illustrate the issues and corresponding measures of flowering regulation investigation. It is of great benefit to the future study of flowering in perennial trees.

Multiple Telescoping Flow Diverter Technique in Endovascular Treatment of a Giant Petrous and Cavernous Carotid Aneurysm.

Using flow diverters (FDs) to treat carotid cavernous aneurysms has achieved favorable clinical and radiologic outcomes. However, the treatment of some giant carotid cavernous aneurysms with FDs remains technically challenging. We report the case of a 24-year-old male who presented with headaches and left facial numbness. Magnetic resonance images and angiography revealed a left giant thrombosed dissecting carotid aneurysm with involvement of the petrous and cavernous segments of the carotid artery. Because this giant aneurysm involved a long segment of the parent artery, the multiple telescoping FD technique was used to ensure adequate neck coverage and enhance the flow-diverting effect for endoluminal reconstruction. A new type of FD, the Lattice flow diversion device (AccuMedical, Beijing, China), was used in this case. Five Lattice FDs were successfully deployed in a telescopic fashion to completely cover the aneurysmal segment from the proximal to distal healthy segment. The patient recovered from the procedure without any complications, and his symptoms had completely resolved at the 3-month follow-up. The angiogram taken at 6 months showed complete remodeling of the internal carotid artery with no aneurysmal opacification. This case highlights the effectiveness of the multiple telescoping FD technique in treatment of long-segment giant petrous and cavernous carotid aneurysms. The technical nuances of the procedure and potential advantages of the Lattice FD are illustrated in this video atlas. Informed patient consent for the procedure and for publication was obtained.

Natural History of Spinal Cord Cavernous Malformations: A Multicenter Cohort Study.

BACKGROUND: The natural history of spinal cord cavernous malformations (SCCMs) remains relatively unclear. OBJECTIVE: To investigate the natural history for hemorrhagic risks and neurological outcomes, as well as relevant predicting factors, of SCCMs. METHODS: All patients between 2002 and 2019 with diagnosis of SCCMs were identified retrospectively. An observational study of patients with conservative management was performed to reveal the natural history of SCCMs. RESULTS: We identified 305 patients in the full cohort, including 126 patients who were conservatively treated for at least 6 months (median observational period, 24.0 months). Forty-five hemorrhage events occurred during 527 person-years of follow-up, yielding an annual hemorrhage rate of 8.5% per person-year. The 1-, 2-, and 5-year cumulative risks of hemorrhage were 13.9%, 26.1%, and 35.1%, respectively. Prior hemorrhage (hazard ratio [HR] = 12.948, P = .012) and pediatric patients (HR = 2.841, P = .031) were independent predictors of hemorrhage in the long-term follow-up. Familial form (adjusted odds ratio [OR] = 30.695, P = .010) and subsequent hemorrhage events (adjusted OR = 16.333, P = .000) were independent risk factors for worsening of neurological function, and baseline neurological status (adjusted OR = 78.984, P = .000) and presence of subsequent hemorrhage (adjusted OR = 9.611, P = .001) were significantly associated with neurological outcomes. CONCLUSION: The natural history of SCCMs varies. Baseline characteristics, such as pediatric patients, familial form, and baseline neurological status, as well as prior and subsequent hemorrhagic events, significantly affect the natural history of the SCCMs, which prompts a differentiated treatment strategy.

Analysis of the wall thickness of intracranial aneurysms: Can computational fluid dynamics detect the translucent areas of saccular intracranial aneurysms and predict the rupture risk preoperatively?

Background and purpose: The translucent area on the surface of intracranial aneurysms (IAs) is associated with rupture risk. In the present study, the Polyflow module of the Ansys software was used to simulate and analyze the thickness of the aneurysm wall to detect whether it was "translucent" and to assess the rupture risk. Methods: Forty-five patients with 48 IAs who underwent microsurgery were retrospectively reviewed. The medical records, radiographic data, and intraoperative images of the patients were collected. The image data were analyzed using computational fluid dynamics (CFD) simulations to explore the relationship between the simulated thickness of the aneurysm wall, the translucent area, and the rupture point of the real aneurysm's surface to predict the rupture risk and provide a certain reference basis for clinical treatment. Results: The Polyflow simulation revealed that the location of the minimum extreme point of the simulated aneurysm wall thickness was consistent with the translucent area or rupture point on the surface of the real aneurysm. There was a downward trend in the correlation between the change rate (IS) in the wall area and volume during aneurysm growth and rupture. Ruptured aneurysms have a greater inhomogeneity coefficient Iδ than the unruptured ones. In the unruptured group, translucent aneurysms also had greater inhomogeneity coefficients Iδ and more significant thickness changes (multiple IBA) than non-translucent ones. Conclusions: The Ansys software Polyflow module could detect whether the unruptured aneurysms were translucent and predict the rupture risk and rupture point. Clinical trial registration: https://clinicaltrials.gov/, Identifier, NCT03133624.

Arteriovenous fistulas in the craniocervical junction region: With vs. without spinal arterial feeders.

Objective: Arteriovenous fistulas (AVFs) in the craniocervical junction (CCJ) region are a rare occurrence with special clinical manifestations. This study retrospectively reviewed patients with CCJ AVFs treated at our neurosurgical center, aiming to enhance the understanding of CCJ AVFs. Methods: A total of 113 patients with CCJ AVFs treated at our neurosurgical center between January 2013 and December 2020 were enrolled. They were grouped as patients with CCJ AVFs with spinal arterial feeders (n = 20) and patients with CCJ AVF without spinal arterial feeders (n = 93). Clinical presentation, angiographic characteristics, intraoperative findings, and treatment outcomes were analyzed. Results: The patients' median age was 55 years (IQR 47.5-62 years). The proportion of males in the group without spinal arterial feeders was significantly higher (p = 0.001). Subarachnoid hemorrhage (SAH) was the most common clinical presentation, especially in the group with spinal arterial feeders (p < 0.001). There were significant differences in AVF type, fistula location, and direction of the venous drainage between the two groups (p < 0.001). Intervention embolization combined with microsurgery was more common in treating AVFs with spinal arterial feeders (p = 0.006). Spinal arterial feeders did not affect the outcome (p = 0.275). Conclusions: SAH was the most common presentation of CCJ AVFs in this study. Microsurgery and interventional embolization were optional treatment strategies. The angioarchitecture of CCJ AVFs was essential for selecting treatment strategies.

Natural History and Clinical Outcomes of Paravertebral Arteriovenous Shunts.

BACKGROUND AND PURPOSE: Paravertebral arteriovenous shunts (PVAVSs) are rare. Whether the intradural venous system is involved in drainage may lead to differences in clinical characteristics through specific pathophysiological mechanisms. This study aims to comprehensively evaluate the natural history and clinical outcomes of PVAVSs with or without intradural drainage. METHODS: Sixty-four consecutive patients with PVAVSs from 2 institutes were retrospectively reviewed. Lesions were classified as type A (n=28) if the intradural veins were involved in drainage; otherwise, they were classified as type B (n=36). The clinical course from initial presentation to the last follow-up was analyzed. RESULTS: The patients with type A shunts were older at presentation (52.5 versus 35.5 years, P<0.0001) and more likely to have lower spinal segments affected than patients with type B PVAVSs (67.8% versus 13.9%, P=0.00006). After presentation, the deterioration rates related to gait and sphincter dysfunction were significantly higher in patients with type A than type B shunts (gait dysfunction: 71.8%/y versus 17.0%/y, P=0.0006; sphincter dysfunction: 63.7%/y versus 11.3%/y, P=0.0002). According to the angiogram at the end of the latest treatment, 79% of type A and 75% of type B PVAVSs were completely obliterated. If the lesions were partially obliterated, a significantly higher clinical deterioration rate was observed in patients with type A shunts than those with type B shunts (69.9%/y versus 3.2%/y, P=0.0253). CONCLUSIONS: Type A PVAVSs feature rapid progressive neurological deficits; therefore, early clinical intervention is necessary. For complex lesions that cannot be completely obliterated, surgical disconnection of all refluxed radicular veins is suggested.