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Kunal P. Raygor, Taemin Oh, Joan Y. Hwang, Ryan R. L. Phelps, Kristen Ghoussaini, Patrick Wong, Rebecca Silvers, Lauren R. Ostling, and Peter P. Sun

OBJECTIVE

Ventriculoperitoneal (VP) shunt infections are common complications after shunt operations. Despite the use of intravenous antibiotics, the incidence of infections remains high. Though antibiotic-impregnated catheters (AICs) are commonly used, another method of infection prophylaxis is the use of intraventricular (IVT) antibiotics. The authors describe their single-institution experience with a standard shunt protocol utilizing prophylactic IVT and topical vancomycin administration and report the incidence of pediatric shunt infections.

METHODS

Three hundred two patients undergoing VP shunt procedures with IVT and topical vancomycin between 2006 and 2016 were included. Patients were excluded if their age at surgery was greater than 18 years. Shunt operations were performed at a single institution following a standard shunt protocol implementing IVT and topical vancomycin. No AICs were used. Clinical data were retrospectively collected from the electronic health records.

RESULTS

Over the 11-year study period, 593 VP shunt operations were performed with IVT and topical vancomycin, and a total of 19 infections occurred (incidence 3.2% per procedure). The majority of infections (n = 10, 52.6%) were caused by Staphylococcus epidermidis. The median time to shunt infection was 3.7 weeks. On multivariate analysis, the presence of a CSF leak (OR 31.5 [95% CI 8.8–112.6]) and age less than 6 months (OR 3.6 [95% CI 1.2–10.7]) were statistically significantly associated with the development of a shunt infection. A post hoc analysis comparing infection rates after procedures that adhered to the shunt protocol and those that did not administer IVT and topical vancomycin, plus historical controls, revealed a difference in infection rates (3.2% vs 6.9%, p = 0.03).

CONCLUSIONS

The use of a standardized shunt operation technique that includes IVT and topical vancomycin is associated with a total shunt infection incidence of 3.2% per procedure, which compares favorably with the reported rates of shunt infection in the literature. The majority of infections occurred within 2 months of surgery and the most common causative organism was S. epidermidis. Young age (< 6 months) at the time of surgery and the presence of a postoperative CSF leak were statistically significantly associated with postoperative shunt infection on multivariate analysis. The results are hypothesis generating, and the authors propose that IVT and topical administration of vancomycin as part of a standardized shunt operation protocol may be an appropriate option for preventing pediatric shunt infections.

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Ethan A. Winkler, John K. Yue, Hansen Deng, Kunal P. Raygor, Ryan R. L. Phelps, Caleb Rutledge, Alex Y. Lu, Roberto Rodriguez Rubio, Jan-Karl Burkhardt, and Adib A. Abla

OBJECTIVE

Cerebral bypass procedures are microsurgical techniques to augment or restore cerebral blood flow when treating a number of brain vascular diseases including moyamoya disease, occlusive vascular disease, and cerebral aneurysms. With advances in endovascular therapy and evolving evidence-based guidelines, it has been suggested that cerebral bypass procedures are in a state of decline. Here, the authors characterize the national trends in cerebral bypass surgery in the United States from 2002 to 2014.

METHODS

Using the National (Nationwide) Inpatient Sample, the authors extracted for analysis the data on all adult patients who had undergone cerebral bypass as indicated by ICD-9-CM procedure code 34.28. Indications for bypass procedures, patient demographics, healthcare costs, and regional variations are described. Results were stratified by indication for cerebral bypass including moyamoya disease, occlusive vascular disease, and cerebral aneurysms. Predictors of inpatient complications and death were evaluated using multivariable logistic regression analysis.

RESULTS

From 2002 to 2014, there was an increase in the annual number of cerebral bypass surgeries performed in the United States. This increase reflected a growth in the number of cerebral bypass procedures performed for adult moyamoya disease, whereas cases performed for occlusive vascular disease or cerebral aneurysms declined. Inpatient complication rates for cerebral bypass performed for moyamoya disease, vascular occlusive disease, and cerebral aneurysm were 13.2%, 25.1%, and 56.3%, respectively. Rates of iatrogenic stroke ranged from 3.8% to 20.4%, and mortality rates were 0.3%, 1.4%, and 7.8% for moyamoya disease, occlusive vascular disease, and cerebral aneurysms, respectively. Multivariate logistic regression confirmed that cerebral bypass for vascular occlusive disease or cerebral aneurysm is a statistically significant predictor of inpatient complications and death. Mean healthcare costs of cerebral bypass remained unchanged from 2002 to 20014 and varied with treatment indication: moyamoya disease $38,406 ± $483, vascular occlusive disease $46,618 ± $774, and aneurysm $111,753 ± $2381.

CONCLUSIONS

The number of cerebral bypass surgeries performed for adult revascularization has increased in the United States from 2002 to 2014. Rising rates of surgical bypass reflect a greater proportion of surgeries performed for moyamoya disease, whereas bypasses performed for vascular occlusive disease and aneurysms are decreasing. Despite evolving indications, cerebral bypass remains an important surgical tool in the modern endovascular era and may be increasing in use. Stagnant complication rates highlight the need for continued interest in advancing available bypass techniques or technologies to improve patient outcomes.

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Kunal P. Raygor, Ryan R. L. Phelps, Caleb Rutledge, Daniel M. S. Raper, Annette Molinaro, Christine K. Fox, Nalin Gupta, and Adib A. Abla

OBJECTIVE

Healthcare disparities are widely described in adults, but barriers affecting access to care for pediatric patients with moyamoya disease (MMD) are unknown. Understanding socioeconomic factors impacting hospital access and outcomes is necessary to address pediatric healthcare disparities.

METHODS

In this cross-sectional observational study, the Kids’ Inpatient Database was used to identify patients admitted with a primary diagnosis of MMD from 2003 to 2016. Patients ≤ 18 years with a primary diagnosis of MMD based on International Classification of Diseases (ICD) codes were included. Hospital admissions were queried for use of cerebral revascularization based on ICD procedure codes.

RESULTS

Query of the KID yielded 1449 MMD hospitalizations. After multivariable regression, Hispanic ethnicity (OR 0.52 [95% CI 0.33–0.81], p = 0.004) was associated with lack of surgical revascularization. Private insurance (OR 1.56 [95% CI 1.15–2.13], p = 0.004), admissions at medium- and high-volume centers (OR 2.01 [95% CI 1.42–2.83], p < 0.001 and OR 2.84 [95% CI 1.95–4.14], p < 0.001, respectively), and elective hospitalization (OR 3.37 [95% CI 2.46–4.64], p < 0.001) were positively associated with revascularization. Compared with Caucasian race, Hispanic ethnicity was associated with increased mean (± SEM) length of stay by 2.01 ± 0.70 days (p = 0.004) and increased hospital charges by $24,333.61 ± $7918.20 (p = 0.002), despite the decreased utilization of surgical revascularization. Private insurance was associated with elective admission (OR 1.50 [95% CI 1.10–2.05], p = 0.01) and admission to high-volume centers (OR 1.90 [95% CI 1.26–2.88], p = 0.002). African American race was associated with the development of in-hospital complications (OR 2.52 [95% CI 1.38–4.59], p = 0.003).

CONCLUSIONS

Among pediatric MMD hospitalizations, multiple socioeconomic factors were associated with access to care, whether surgical treatment is provided, and whether in-hospital complications occur. These results suggest that socioeconomic factors are important drivers of healthcare disparities in children with MMD and warrant further study.

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Ridhima Guniganti, Enrico Giordan, Ching-Jen Chen, Isaac Josh Abecassis, Michael R. Levitt, Andrew Durnford, Jessica Smith, Edgar A. Samaniego, Colin P. Derdeyn, Amanda Kwasnicki, Ali Alaraj, Adriaan R. E. Potgieser, Samir Sur, Stephanie H. Chen, Yoshiteru Tada, Ethan Winkler, Ryan R. L. Phelps, Pui Man Rosalind Lai, Rose Du, Adib Abla, Junichiro Satomi, Robert M. Starke, J. Marc C. van Dijk, Sepideh Amin-Hanjani, Minako Hayakawa, Bradley A. Gross, W. Christopher Fox, Diederik Bulters, Louis J. Kim, Jason Sheehan, Giuseppe Lanzino, Jay F. Piccirillo, Akash P. Kansagra, Gregory J. Zipfel, and

OBJECTIVE

Cranial dural arteriovenous fistulas (dAVFs) are rare lesions, hampering efforts to understand them and improve their care. To address this challenge, investigators with an established record of dAVF investigation formed an international, multicenter consortium aimed at better elucidating dAVF pathophysiology, imaging characteristics, natural history, and patient outcomes. This report describes the design of the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) and includes characterization of the 1077-patient cohort.

METHODS

Potential collaborators with established interest in the field were identified via systematic review of the literature. To ensure uniformity of data collection, a quality control process was instituted. Data were retrospectively obtained.

RESULTS

CONDOR comprises 14 centers in the United States, the United Kingdom, the Netherlands, and Japan that have pooled their data from 1077 dAVF patients seen between 1990 and 2017. The cohort includes 359 patients (33%) with Borden type I dAVFs, 175 (16%) with Borden type II fistulas, and 529 (49%) with Borden type III fistulas. Overall, 852 patients (79%) presented with fistula-related symptoms: 427 (40%) presented with nonaggressive symptoms such as tinnitus or orbital phenomena, 258 (24%) presented with intracranial hemorrhage, and 167 (16%) presented with nonhemorrhagic neurological deficits. A smaller proportion (224 patients, 21%), whose dAVFs were discovered incidentally, were asymptomatic. Many patients (85%, 911/1077) underwent treatment via endovascular embolization (55%, 587/1077), surgery (10%, 103/1077), radiosurgery (3%, 36/1077), or multimodal therapy (17%, 184/1077). The overall angiographic cure rate was 83% (758/911 treated), and treatment-related permanent neurological morbidity was 2% (27/1467 total procedures). The median time from diagnosis to follow-up was 380 days (IQR 120–1038.5 days).

CONCLUSIONS

With more than 1000 patients, the CONDOR registry represents the largest registry of cranial dAVF patient data in the world. These unique, well-annotated data will enable multiple future analyses to be performed to better understand dAVFs and their management.

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Isaac Josh Abecassis, R. Michael Meyer, Michael R. Levitt, Jason P. Sheehan, Ching-Jen Chen, Bradley A. Gross, Jessica Smith, W. Christopher Fox, Enrico Giordan, Giuseppe Lanzino, Robert M. Starke, Samir Sur, Adriaan R. E. Potgieser, J. Marc C. van Dijk, Andrew Durnford, Diederik Bulters, Junichiro Satomi, Yoshiteru Tada, Amanda Kwasnicki, Sepideh Amin-Hanjani, Ali Alaraj, Edgar A. Samaniego, Minako Hayakawa, Colin P. Derdeyn, Ethan Winkler, Adib Abla, Pui Man Rosalind Lai, Rose Du, Ridhima Guniganti, Akash P. Kansagra, Gregory J. Zipfel, Louis J. Kim, and

OBJECTIVE

Cranial dural arteriovenous fistulas (dAVFs) are often treated with endovascular therapy, but occasionally a multimodality approach including surgery and/or radiosurgery is utilized. Recurrence after an initial angiographic cure has been reported, with estimated rates ranging from 2% to 14.3%, but few risk factors have been identified. The objective of this study was to identify risk factors associated with recurrence of dAVF after putative cure.

METHODS

The Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) data were retrospectively reviewed. All patients with angiographic cure after treatment and subsequent angiographic follow-up were included. The primary outcome was recurrence, with risk factor analysis. Secondary outcomes included clinical outcomes, morbidity, and mortality associated with recurrence. Risk factor analysis was performed comparing the group of patients who experienced recurrence with those with durable cure (regardless of multiple recurrences). Time-to-event analysis was performed using all collective recurrence events (multiple per patients in some cases).

RESULTS

Of the 1077 patients included in the primary CONDOR data set, 457 met inclusion criteria. A total of 32 patients (7%) experienced 34 events of recurrence at a mean of 368.7 days (median 192 days). The recurrence rate was 4.5% overall. Kaplan-Meier analysis predicted long-term recurrence rates approaching 11% at 3 years. Grade III dAVFs treated with endovascular therapy were statistically significantly more likely to experience recurrence than those treated surgically (13.3% vs 0%, p = 0.0001). Tentorial location, cortical venous drainage, and deep cerebral venous drainage were all risk factors for recurrence. Endovascular intervention and radiosurgery were associated with recurrence. Six recurrences were symptomatic, including 2 with hemorrhage, 3 with nonhemorrhagic neurological deficit, and 1 with progressive flow-related symptoms (decreased vision).

CONCLUSIONS

Recurrence of dAVFs after putative cure can occur after endovascular treatment. Risk factors include tentorial location, cortical venous drainage, and deep cerebral drainage. Multimodality therapy can be used to achieve cure after recurrence. A delayed long-term angiographic evaluation (at least 1 year from cure) may be warranted, especially in cases with risk factors for recurrence.

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Isaac Josh Abecassis, R. Michael Meyer, Michael R. Levitt, Jason P. Sheehan, Ching-Jen Chen, Bradley A. Gross, Ashley Lockerman, W. Christopher Fox, Waleed Brinjikji, Giuseppe Lanzino, Robert M. Starke, Stephanie H. Chen, Adriaan R. E. Potgieser, J. Marc C. van Dijk, Andrew Durnford, Diederik Bulters, Junichiro Satomi, Yoshiteru Tada, Amanda Kwasnicki, Sepideh Amin-Hanjani, Ali Alaraj, Edgar A. Samaniego, Minako Hayakawa, Colin P. Derdeyn, Ethan Winkler, Adib Abla, Pui Man Rosalind Lai, Rose Du, Ridhima Guniganti, Akash P. Kansagra, Gregory J. Zipfel, Louis J. Kim, and

OBJECTIVE

There is a reported elevated risk of cerebral aneurysms in patients with intracranial dural arteriovenous fistulas (dAVFs). However, the natural history, rate of spontaneous regression, and ideal treatment regimen are not well characterized. In this study, the authors aimed to describe the characteristics of patients with dAVFs and intracranial aneurysms and propose a classification system.

METHODS

The Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database from 12 centers was retrospectively reviewed. Analysis was performed to compare dAVF patients with (dAVF+ cohort) and without (dAVF-only cohort) concomitant aneurysm. Aneurysms were categorized based on location as a dAVF flow-related aneurysm (FRA) or a dAVF non–flow-related aneurysm (NFRA), with further classification as extra- or intradural. Patients with traumatic pseudoaneurysms or aneurysms with associated arteriovenous malformations were excluded from the analysis. Patient demographics, dAVF anatomical information, aneurysm information, and follow-up data were collected.

RESULTS

Of the 1077 patients, 1043 were eligible for inclusion, comprising 978 (93.8%) and 65 (6.2%) in the dAVF-only and dAVF+ cohorts, respectively. There were 96 aneurysms in the dAVF+ cohort; 10 patients (1%) harbored 12 FRAs, and 55 patients (5.3%) harbored 84 NFRAs. Dural AVF+ patients had higher rates of smoking (59.3% vs 35.2%, p < 0.001) and illicit drug use (5.8% vs 1.5%, p = 0.02). Sixteen dAVF+ patients (24.6%) presented with aneurysm rupture, which represented 16.7% of the total aneurysms. One patient (1.5%) had aneurysm rupture during follow-up. Patients with dAVF+ were more likely to have a dAVF located in nonconventional locations, less likely to have arterial supply to the dAVF from external carotid artery branches, and more likely to have supply from pial branches. Rates of cortical venous drainage and Borden type distributions were comparable between cohorts. A minority (12.5%) of aneurysms were FRAs. The majority of the aneurysms underwent treatment via either endovascular (36.5%) or microsurgical (15.6%) technique. A small proportion of aneurysms managed conservatively either with or without dAVF treatment spontaneously regressed (6.2%).

CONCLUSIONS

Patients with dAVF have a similar risk of harboring a concomitant intracranial aneurysm unrelated to the dAVF (5.3%) compared with the general population (approximately 2%–5%) and a rare risk (0.9%) of harboring an FRA. Only 50% of FRAs are intradural. Dural AVF+ patients have differences in dAVF angioarchitecture. A subset of dAVF+ patients harbor FRAs that may regress after dAVF treatment.

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Edgar A. Samaniego, Jorge A. Roa, Minako Hayakawa, Ching-Jen Chen, Jason P. Sheehan, Louis J. Kim, Isaac Josh Abecassis, Michael R. Levitt, Ridhima Guniganti, Akash P. Kansagra, Giuseppe Lanzino, Enrico Giordan, Waleed Brinjikji, Diederik Bulters, Andrew Durnford, W. Christopher Fox, Adam J. Polifka, Bradley A. Gross, Sepideh Amin-Hanjani, Ali Alaraj, Amanda Kwasnicki, Robert M. Starke, Samir Sur, J. Marc C. van Dijk, Adriaan R. E. Potgieser, Junichiro Satomi, Yoshiteru Tada, Adib Abla, Ethan Winkler, Rose Du, Pui Man Rosalind Lai, Gregory J. Zipfel, Colin P. Derdeyn, and

OBJECTIVE

Current evidence suggests that intracranial dural arteriovenous fistulas (dAVFs) without cortical venous drainage (CVD) have a benign clinical course. However, no large study has evaluated the safety and efficacy of current treatments and their impact over the natural history of dAVFs without CVD.

METHODS

The authors conducted an analysis of the retrospectively collected multicenter Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database. Patient demographics and presenting symptoms, angiographic features of the dAVFs, and treatment outcomes of patients with Borden type I dAVFs were reviewed. Clinical and radiological follow-up information was assessed to determine rates of new intracranial hemorrhage (ICH) or nonhemorrhagic neurological deficit (NHND), worsening of venous hyperdynamic symptoms (VHSs), angiographic recurrence, and progression or spontaneous regression of dAVFs over time.

RESULTS

A total of 342 patients/Borden type I dAVFs were identified. The mean patient age was 58.1 ± 15.6 years, and 62% were women. The mean follow-up time was 37.7 ± 54.3 months. Of 230 (67.3%) treated dAVFs, 178 (77%) underwent mainly endovascular embolization, 11 (4.7%) radiosurgery alone, and 4 (1.7%) open surgery as the primary modality. After the first embolization, most dAVFs (47.2%) achieved only partial reduction in early venous filling. Multiple complementary interventions increased complete obliteration rates from 37.9% after first embolization to 46.7% after two or more embolizations, and 55.2% after combined radiosurgery and open surgery. Immediate postprocedural complications occurred in 35 dAVFs (15.2%) and 6 (2.6%) with permanent sequelae. Of 127 completely obliterated dAVFs by any therapeutic modality, 2 (1.6%) showed angiographic recurrence/recanalization at a mean of 34.2 months after treatment. Progression to Borden-Shucart type II or III was documented in 2.2% of patients and subsequent development of a new dAVF in 1.6%. Partial spontaneous regression was found in 22 (21.4%) of 103 nontreated dAVFs. Multivariate Cox regression analysis demonstrated that older age, NHND, or severe venous-hyperdynamic symptoms at presentation and infratentorial location were associated with worse prognosis. Kaplan-Meier curves showed no significant difference for stable/improved symptoms survival probability in treated versus nontreated dAVFs. However, estimated survival times showed better trends for treated dAVFs compared with nontreated dAVFs (288.1 months vs 151.1 months, log-rank p = 0.28). This difference was statistically significant for treated dAVFs with 100% occlusion (394 months, log-rank p < 0.001).

CONCLUSIONS

Current therapeutic modalities for management of dAVFs without CVD may provide better symptom control when complete angiographic occlusion is achieved.

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Ching-Jen Chen, Thomas J. Buell, Dale Ding, Ridhima Guniganti, Akash P. Kansagra, Giuseppe Lanzino, Enrico Giordan, Louis J. Kim, Michael R. Levitt, Isaac Josh Abecassis, Diederik Bulters, Andrew Durnford, W. Christopher Fox, Adam J. Polifka, Bradley A. Gross, Minako Hayakawa, Colin P. Derdeyn, Edgar A. Samaniego, Sepideh Amin-Hanjani, Ali Alaraj, Amanda Kwasnicki, J. Marc C. van Dijk, Adriaan R. E. Potgieser, Robert M. Starke, Samir Sur, Junichiro Satomi, Yoshiteru Tada, Adib A. Abla, Ethan A. Winkler, Rose Du, Pui Man Rosalind Lai, Gregory J. Zipfel, Jason P. Sheehan, and

OBJECTIVE

The risk-to-benefit profile of treating an unruptured high-grade dural arteriovenous fistula (dAVF) is not clearly defined. The aim of this multicenter retrospective cohort study was to compare the outcomes of different interventions with observation for unruptured high-grade dAVFs.

METHODS

The authors retrospectively reviewed dAVF patients from 12 institutions participating in the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR). Patients with unruptured high-grade (Borden type II or III) dAVFs were included and categorized into four groups (observation, embolization, surgery, and stereotactic radiosurgery [SRS]) based on the initial management. The primary outcome was defined as the modified Rankin Scale (mRS) score at final follow-up. Secondary outcomes were good outcome (mRS scores 0–2) at final follow-up, symptomatic improvement, all-cause mortality, and dAVF obliteration. The outcomes of each intervention group were compared against those of the observation group as a reference, with adjustment for differences in baseline characteristics.

RESULTS

The study included 415 dAVF patients, accounting for 29, 324, 43, and 19 in the observation, embolization, surgery, and SRS groups, respectively. The mean radiological and clinical follow-up durations were 21 and 25 months, respectively. Functional outcomes were similar for embolization, surgery, and SRS compared with observation. With observation as a reference, obliteration rates were higher after embolization (adjusted OR [aOR] 7.147, p = 0.010) and surgery (aOR 33.803, p < 0.001) and all-cause mortality was lower after embolization (imputed, aOR 0.171, p = 0.040). Hemorrhage rates per 1000 patient-years were 101 for observation versus 9, 22, and 0 for embolization (p = 0.022), surgery (p = 0.245), and SRS (p = 0.077), respectively. Nonhemorrhagic neurological deficit rates were similar between each intervention group versus observation.

CONCLUSIONS

Embolization and surgery for unruptured high-grade dAVFs afforded a greater likelihood of obliteration than did observation. Embolization also reduced the risk of death and dAVF-associated hemorrhage compared with conservative management over a modest follow-up period. These findings support embolization as the first-line treatment of choice for appropriately selected unruptured Borden type II and III dAVFs.