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1492 citation(s) found for "Ian, G".

Abstract 16933: A Decision Aid for the Use of PCSK9 Inhibitors in Patients With Familial Hypercholesterolemia
Shaw, Kevin, Hargraves, Ian , Farwati, Medhat , Montori, Víctor M. , Kullo, Iftikhar J.

Circulation | April 23, 2024 | Volume: 138 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.138.suppl_1.16933 Get It

Introduction: Familial Hypercholesterolemia (FH) is a common inherited disorder of lipid metabolism. FH patients are at an increased risk of atherosclerotic cardiovascular disease (ASCVD) due to elevated low-density lipoprotein cholesterol (LDL-C) levels. Patients with FH may not reach target LDL-C levels despite maximally tolerated statin (±ezetimibe) therapy (MTT). The AHA scientific statement on FH highlighted the need for developing decision aids (DAs) to facilitate shared decision making (SDM) regarding additional therapy including PCSK9 inhibitors. Methods: A user-centered design process was initiated to understand FH treatment decisions and to develop prototype interventions. Patients with FH had their diagnosis confirmed by genetic testing. Encounters between FH patients and health care providers were video recorded and analyzed to assess how decisions are made regarding lipid lowering therapy. Nine encounters were recorded: 3 with a genetic counselor and 6 with an FH specialist. Informed by clinical encounters and literature review, we developed content for a DA related to available therapeutic options for FH patients on MTT. Results: A prototype online DA was created to support in-encounter discussion of a patient’s risk of adverse cardiovascular events and which therapies may be best suited to the patient (Figure). 5 and 10-year ASCVD risk is estimated using the SAFEHEART Risk Score (SRS). Risk is communicated in numbers using a 100-person icon array and the language “Out of 100 persons like you...”. Therapeutic options include watchful waiting, bile acid sequestrants, and PCSK9 inhibitors. For each option, the degree of risk reduction, costs, and side effects are presented. The tool is currently being refined by analyzing additional encounters with FH patients. Conclusion: We developed an interactive prototype DA to facilitate SDM for FH patients on MTT. After further iterative testing the tool will be deployed in the electronic health record.
Abstract 8952: Results of the Pediatric Lead Extractability and Survival Evaluation (PLEASE) Study
Berul, Charles I. , Freedenberg, Vicki , Balaji, Seshadri, Bar‐Cohen, Yaniv , Batra, Anjan S. , Cannon, Bryan C. , Ceresnak, Scott R. , Collins, Kathryn K. , Erickson, Christopher C. , Franklin, Wayne H., Kertesz, Naomi J. , Moak, Jeffrey P. , Papagiannis, John , Paul, Thomas , Tanel, Ronn E. , Tisma-Dupanovic, Svetlana, Zimmerman, Frank, Cecchin, Frank , Atallah, Joseph , Balaji, Seshadri , Chun, Terrence , Dubin, Anne M. , LaPage, Martin J , Law, Ian H. , Tisma‐Dupanovic, Svetlana, Wilkoff, Bruce L.

Circulation | April 23, 2024 | Volume: 124 | Issue: suppl_21 | Pages: No page available

10.1161/circ.124.suppl_21.a8952 Get It

Implantable cardioverter-defibrillator (ICD) therapy in children and congenital heart disease (CHD) patients is hampered by poor long-term lead survival. Lead extraction is technically difficult and carries substantial morbidity. Manufacturers developed distinct strategies for this issue: thinner lead bodies or a Gore ePTFE coil coating. Both design changes were thought to improve ease of lead removal, but have not been directly compared in children or adults. The purpose of this study was to assess thin and ePTFE-coated ICD lead survival in pediatric and CHD pts. Methods: The Pediatric Lead Extractability and Survival Evaluation (PLEASE) Study began as a Phase IV multicenter open-label prospective study [ NCT00335036 ], facilitated by the Pediatric & Congenital EP Society. Initially designed as a randomized study, it changed to a parallel assignment registry when 1 lead had an advisory due to high incidence of failure, prompting concern about continued clinical equipoise. Pediatric and CHD pts who underwent ICD lead implant from 2005-2010 were eligible. The end date was NCDR ICD Registry v2.0 release (includes pediatric & lead data). 23 centers participated; each site obtained IRB approval. De-identified data was sent to the PI center for verification and statistical analyses. Results: A total of 982 ICD pts (357 VVI, 558 DDD, 67 CRT-D) entered the PLEASE study, incl. 423 pts (43%) with CHD. Mean age at implant = 18.3 ± 9.9 yrs. Thin (< 7Fr) ICD leads accounted for 51%, 23% were ePTFE-coated, 26% neither thin nor coated. There were 113 ICD lead failures (11.5%) at a mean lead-age of 2.2 ± 1.7 yrs, causing shocks in 55 pts. Failure occurred in 21% of thin leads vs 3.5% of ePTFE leads (p<0.01). Extraction was performed on 142 (14.5%) leads overall; 21% of thin leads (incl. extraction of 29 functioning leads due to recall) vs. 4.4% of ePTFE leads (p<0.01). There were 7 major extraction complications (4.9%), but no procedural mortality. Among thin leads, 90/270 (33.3%) of recalled leads failed vs 15/229 (6.6%) non-recalled thin leads. Conclusions: This Phase IV study demonstrates that ICD leads in children and CHD pts have suboptimal performance overall. Thinner leads were much more likely to fail and/or be extracted compared with ePTFE leads, chiefly driven by one lead type.
Abstract 4937: A Novel Molecular Imaging Sensor of Cellular Oxidative Stress
Chen, Ian Y. , Simari, Robert D., Gambhir, Sanjiv S. , Rodriguez‐Porcel, Martin , Peterson, Karen M. , Lerman, Amir

Circulation | April 23, 2024 | Volume: 120 | Issue: suppl_18 | Pages: No page available

10.1161/circ.120.suppl_18.s1025-a Get It

Increased oxidative stress has been suggested to play an important role in the biology of mesenchymal stem cells (MSCs). However, little is known of the effect of increased oxidative stress in-vivo, partly due to the lack of appropriate imaging technologies for monitoring of stem cell biology in the living subject. Recent developments in molecular imaging permit, for the first time, the longitudinal monitoring of stem cell biology in vivo. We hypothesize that changes in oxidative stress can be monitored using a reporter gene strategy (molecular imaging). Methods: We have developed a novel oxidative stress sensor, using a two-step transcriptional amplification strategy to enhance the expression of firefly luciferase (Fluc), driven by the pro-oxidant enzyme NAD(P)H promoter, and used to monitor oxidative stress in rMSCs. rMSCs was induced by hypoxia (1% O2 for 24 hours) and serum deprivation (SD) and confirmed using a dichlorofluorescein colorimetric assay (measures the production of hydrogen peroxide-H2O2-) and NAD(P)H protein expression. Results: Both serum deprivation and hypoxia led to a pro-oxidant state (Fig. A–B ). Most importantly, increased oxidative stress led to increased activity of the novel reporter gene sensor (Fig. C ) which was decreased in the presence of antioxidants (superoxide dismuatse mimetic Tempol, 5mM, SD+T, Fig D ). Results were reproduced in a different cell type (rat cardiomyoblast, data not shown). Conclusion: Changes in oxidative stress in MSCs can be monitored using molecular imaging. Reporter Gene-based Molecular Imaging, a strategy that is clinically applicable, provides the opportunity to monitor stem cell survival in the living subject.
Hemoadsorption: consensus report of the 30th Acute Disease Quality Initiative workgroup
Bellomo, Rinaldo , Ankawi, Ghada , Baldwin, Ian , Bottari, Gabriella , Clark, William R. , Rosa, Silvia De , Fuhrman, Dana Y. , Goldstein, Stuart L. , Gómez, Hernando , Joannidis, Michael , Lorenzin, Anna , Murugan, Ragi, Premužić, Vedran , Prowle, John R. , Rimmelé, Thomas , Rosner, Mitch, Schneider, Antoine , Zarbock, Alexander , Bagshaw, Sean M. , Basu, Rajit K. , Cantaluppi, Vincenzo , Forni, Lui G. , Husain‐Syed, Faeq , Kashani, Kianoush , Mehta, Ravindra L. , Murray, Patrick T. , Ostermann, Marlies , Pannu, Neesh , Reis, Thiago , Ronco, Claudio , Rosner, Mitchell H. , See, Emily , Soranno, Danielle E. , Villa, Gianluca , Whaley‐Connell, Adam T.

Nephrology Dialysis Transplantation | April 13, 2024 | Volume: 39 | Issue: 12 | Pages: 1945-1964

10.1093/ndt/gfae089 | PMID 38621759 Get It

ABSTRACT Adsorption-based extracorporeal therapies have been subject to technical developments and clinical application for close to five decades. More recently, new technological developments in membrane and sorbent manipulation have made it possible to deliver more biocompatible extracorporeal adsorption therapies to patients with a variety of conditions. There are several key rationales based on physicochemical principles and clinical considerations that justify the application and investigation of such therapies as evidenced by multiple ex vivo, experimental and clinical observations. Accordingly, unspecific adsorptive extracorporeal therapies have now been applied to the treatment of a wide array of conditions from poisoning to drug overdoses, to inflammatory states and sepsis, and acute or chronic liver and kidney failure. In response to the rapidly expanding knowledge base and increased clinical evidence, we convened an Acute Disease Quality Initiative consensus conference dedicated to such treatment. The data show that hemoadsorption has clinically acceptable short-term biocompatibility and safety, technical feasibility and experimental demonstration of specified target molecule removal. Pilot studies demonstrate potentially beneficial effects on physiology and larger studies of endotoxin-based hemoadsorption have identified possible target phenotypes for larger randomized controlled trials. Moreover, in a variety of endogenous and exogenous intoxications, removal of target molecules has been confirmed in vivo. However, some studies have raised concerns about harm, or failed to deliver benefits. Thus, despite many achievements, modern hemoadsorption remains a novel and experimental intervention with limited data, and a large research agenda.
Radiology-pathology correlation: Giant tumefactive perivascular spaces
Benson, John C. , Trejo‐Lopez, Jorge , Cormier, Jason L, Mark, Ian T. , Madhavan, Ajay A. , Rydberg, Charlotte H. , Eckel, Laurence J. , Trejo-Lopez, Jorge A, Mark, Ian , Madhavan, Ajay A , Kotsenas, Amy L. , Johnson, Derek R , Benson, John , Parney, Ian F. , Luetmer, Patrick H. , Johnson, Derek R.

The Neuroradiology Journal | April 13, 2024 | Volume: 38 | Issue: 2 | Pages: 233-237

10.1177/19714009241247459 | PMID 38613202 Get It

Dilated perivascular spaces (PVSs) are common and easily recognized on imaging. However, rarer giant tumefactive PVSs (GTPVSs) can have unusual multilocular cystic configurations, and are often confused for other pathologic entities, including neoplasms, cystic infarctions, and neuroepithelial cysts. Because GTPVSs are scarcely encountered and even more infrequently operated upon, many radiologists are unaware of the imaging and pathologic features of these lesions. Here, a case of a resected GTPVS is presented, highlighting both its radiologic and histologic characteristics, and discussing how such lesions can be differentiated from their closest mimickers on imaging.
Unplanned returns to the operating room: a quality improvement methodology for the comparison of institutional outcomes to national benchmarks
Mikula, Anthony L. , Kerezoudis, Panagiotis , Biedermann, Aaron, Bydon, Mohamad , Biedermann, Aaron J, Michalopoulos, Giorgos D. , Parney, Ian F. , Gompel, Jamie J. Van

Journal of Neurosurgery | April 13, 2024 | Volume: 141 | Issue: 3 | Pages: 804-814

10.3171/2024.1.jns221492 | PMID 38608305 Get It

OBJECTIVE Unplanned returns to the operating room (RORs) constitute an important quality metric in surgical practice. In this study, the authors present a methodology to compare a department’s unplanned ROR rates with national benchmarks in the context of large-scale quality of care surveillance. METHODS The authors identified unplanned RORs within 30 days from the initial surgery at their institution during the period 2014–2018 using an institutional documentation platform that facilitates the collection of reoperation information by providers in the clinical setting. They divided the procedures into 28 groups by Current Procedural Terminology and International Classification of Diseases, 9th and 10th Revision codes. They estimated national benchmarks of unplanned RORs for these procedure groups via querying the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) registry during the period 2014–2018. Finally, they numerically assessed the unplanned ROR rates at their institution compared with those calculated from the ACS NSQIP registry. RESULTS Using the above methodology, the authors were able to classify 12,575 of the cases performed in their department during the period of interest, including 6037 (48%) cranial cases and 6538 (52%) spinal or peripheral nerve cases. Among those, 161 (1.3%) presented with complications that required an unplanned ROR within 30 days from the initial surgery. The respective cumulative unplanned ROR rate in the ACS NSQIP registry during the same timeframe was 3.6%. Among 15 categories of cranial procedures, the cumulative unplanned ROR rate was 1.3% in the authors’ department and 5.6% in the ACS NSQIP registry. Among 13 categories of spinal and peripheral nerve procedures, the cumulative unplanned ROR rate was 1.3% in the authors’ department and 2.8% in the ACS NSQIP registry. Unplanned ROR rates at the authors’ institution were lower than the national average for each of the 28 procedure groups of interest. Yearly analysis of institutional ROR rates for the five most commonly performed procedures showed lower reoperation rates compared with the national benchmarks. CONCLUSIONS Using an institutional documentation tool and a widely available national database, the authors developed a reproducible and standardized method of comparing their department’s outcomes with national benchmarks per procedure subgroup. This methodology accommodates longitudinal quality surveillance across the different subspecialties in a neurosurgical department and may illuminate potential shortcomings of care delivery in the future.
Outcome of lung transplantation in patients with pulmonary alveolar microlithiasis in the era of COVID-19 infection
Raavi, Lekhya , Garg, Pankaj , Alomari, Mohammad , Celik, Nafiye Busra , Makey, Ian A. , Thomas, Mathew , Nassar, Aziza , Sareyyüpoğlu, Başar , Jacob, Samuel , Ahmed, Magdy M. El‐Sayed , Thomas, Mathew , Celik, Nafiye B, Pham, Si M. , Nassar, Aziza , Thomas, Mathew , Garg, Pankaj

Journal of Surgical Case Reports | April 11, 2024 | Volume: 2024 | Issue: 4 | Pages: No page available

10.1093/jscr/rjae211 | PMID 38605700 Get It

Abstract Lung transplant recipients are at higher risk of developing COVID-19 infection compared to other solid organ transplants. The risk further increases in the unvaccinated patients. We present a case of a 43-year-old male who underwent bilateral sequential lung transplantation for pulmonary alveolar microlithiasis (PAM) and had an uneventful recovery. However, two years post-transplantation, the patient developed chronic lung allograft dysfunction (CLAD) with bronchiolitis obliterans syndrome and two episodes of COVID-19 infection. During the second episode of COVID-19 infection, the patient developed sepsis and multi-organ dysfunction ultimately resulting in death. Our case report highlights the increased susceptibility of PAM patients’ post-lung transplant to COVID-19 infection. Continuous follow-up of PAM patients’ post-lung transplantation is necessary to prevent unfavorable outcomes.
Reliability and Validity of Smartphone Cognitive Testing for Frontotemporal Lobar Degeneration
Staffaroni, Adam M. , Clark, Annie L , Taylor, Jack C. , Heuer, Hilary W. , Wise, Amy B. , Dhanam, Sreya , Wolf, Amy , Manoochehri, Masood , Forsberg, Leah K. , Mester, Carly , Rankin, Katherine P. , Clark, David , Darby, R. Ryan , Domoto‐Reilly, Kimiko , Fields, Julie A. , Geschwind, Daniel H. , Ghoshal, Nupur , Graff‐Radford, Neill R. , Huey, Edward D. , Masdeu, Joseph C. , Massimo, Lauren , Mendez, Mario F. , Miyagawa, Toji , Pascual, Belén , Pressman, Peter , Ramos, Eliana Marisa , Rascovsky, Katya, Roberson, Erik D. , Wong, Bonnie , Kornak, John , Kremers, Walter K. , Hassenstab, Jason , Kramer, Joel H. , Rosen, Howard J. , Boxer, Adam L. , Apostolova, Liana G. , Barmada, Sami J. , Brushaber, Danielle , Day, Gregg S, Dickerson, Bradford, Faber, Kelley, Fagan, Anne M. , Foroud, Tatiana M., Gavrilova, Ralitza H. , Graff‐Radford, Jonathan , Grant, Ian , Hall, Matthew , Hales, Chadwick M. , Huang, Eric J. , Johnson, Noah R. , Kolander, Tyler, Kwan, Justin , Lago, Argentina Lario , Lavigne, Shannon B., Lee, Suzee, Ljubenkov, Peter A. , Lucente, Diane , Mackenzie, Ian R. , McGinnis, Scott, Molden, Joie, Naasan, Georges , Onyike, Chiadi U. , Petrucelli, Leonard , Rademakers, Rosa , Rao, Meghana , Rhoads, Kristoffer , Ritter, Aaron, Rogalskı, Emily , Savica, Rodolfo , Sullivan, Anne C. , Syrjanen, Jeremy M., Weıntraub, Sandra , Wint, Dylan , Yokoyoma, Jennifer, Roberson, Erik , Pascual, Belen , Hassenstab, Jason , Kremers, Walter K , Domoto-Reilly, Kimiko , Barmada, Sami , Sanderson‐Cimino, Mark , Cobigo, Yann , Appleby, Brian S. , Bayram, Ece , Bozoki, Andrea C , Galasko, Douglas , Grossman, Murray , Hsiung, Ging‐Yuek Robin , Jones, David T. , Lapid, Maria I. , Litvan, Irene , Masdeu, Joseph C , Ramanan, Vijay K. , Tartaglia, Maria Carmela , Miller, Bruce L. , Boeve, Bradley F. , Botha, Hugo , Day, Gregg S, Dickson, Dennis W. , Elahi, Fanny M. , Fong, Jamie , Gendron, Tania F. , Goldman, Jill , Honig, Lawrence S. , Irwin, David J. , Johnson, Noah, Kantarci, Kejal , Knopman, David S. , Léger, Gabriel C. , McMillan, Corey T. , Pantelyat, Alexander , Paolillo, Emily W. , Paulson, Henry L. , Rexach, Jessica E. , Rojas, Julio C. , Seeley, William W. , Snyder, Allison , Sullivan, Anne C., Tipton, Philip W. , Vandebergh, Marijne , Toga, Arthur W. , VandeVrede, Lawren , Wszołek, Zbigniew K.

JAMA Network Open | April 1, 2024 | Volume: 7 | Issue: 4 | Pages: e244266

10.1001/jamanetworkopen.2024.4266 | PMID 38558141 Get It

ImportanceFrontotemporal lobar degeneration (FTLD) is relatively rare, behavioral and motor symptoms increase travel burden, and standard neuropsychological tests are not sensitive to early-stage disease. Remote smartphone-based cognitive assessments could mitigate these barriers to trial recruitment and success, but no such tools are validated for FTLD.ObjectiveTo evaluate the reliability and validity of smartphone-based cognitive measures for remote FTLD evaluations.Design, Setting, and ParticipantsIn this cohort study conducted from January 10, 2019, to July 31, 2023, controls and participants with FTLD performed smartphone application (app)–based executive functioning tasks and an associative memory task 3 times over 2 weeks. Observational research participants were enrolled through 18 centers of a North American FTLD research consortium (ALLFTD) and were asked to complete the tests remotely using their own smartphones. Of 1163 eligible individuals (enrolled in parent studies), 360 were enrolled in the present study; 364 refused and 439 were excluded. Participants were divided into discovery (n = 258) and validation (n = 102) cohorts. Among 329 participants with data available on disease stage, 195 were asymptomatic or had preclinical FTLD (59.3%), 66 had prodromal FTLD (20.1%), and 68 had symptomatic FTLD (20.7%) with a range of clinical syndromes.ExposureParticipants completed standard in-clinic measures and remotely administered ALLFTD mobile app (app) smartphone tests.Main Outcomes and MeasuresInternal consistency, test-retest reliability, association of smartphone tests with criterion standard clinical measures, and diagnostic accuracy.ResultsIn the 360 participants (mean [SD] age, 54.0 [15.4] years; 209 [58.1%] women), smartphone tests showed moderate-to-excellent reliability (intraclass correlation coefficients, 0.77-0.95). Validity was supported by association of smartphones tests with disease severity (r range, 0.38-0.59), criterion-standard neuropsychological tests (r range, 0.40-0.66), and brain volume (standardized β range, 0.34-0.50). Smartphone tests accurately differentiated individuals with dementia from controls (area under the curve [AUC], 0.93 [95% CI, 0.90-0.96]) and were more sensitive to early symptoms (AUC, 0.82 [95% CI, 0.76-0.88]) than the Montreal Cognitive Assessment (AUC, 0.68 [95% CI, 0.59-0.78]) (z of comparison, −2.49 [95% CI, −0.19 to −0.02]; P = .01). Reliability and validity findings were highly similar in the discovery and validation cohorts. Preclinical participants who carried pathogenic variants performed significantly worse than noncarrier family controls on 3 app tasks (eg, 2-back β = −0.49 [95% CI, −0.72 to −0.25]; P &amp;lt; .001) but not a composite of traditional neuropsychological measures (β = −0.14 [95% CI, −0.42 to 0.14]; P = .32).Conclusions and RelevanceThe findings of this cohort study suggest that smartphones could offer a feasible, reliable, valid, and scalable solution for remote evaluations of FTLD and may improve early detection. Smartphone assessments should be considered as a complementary approach to traditional in-person trial designs. Future research should validate these results in diverse populations and evaluate the utility of these tests for longitudinal monitoring.
Intracranial findings in spontaneous intracranial hypotension: Does the severity of abnormalities correspond with certainty and/or multifocality of cerebrospinal fluid leaks?
Benson, John C. , Mark, Ian T. , Madhavan, Ajay A. , Johnson‐Tesch, Benjamin A., Kim, Dong Kun , Brinjikji, Waleed , Verdoorn, Jared T. , Johnson-Tesch, Benjamin, Diehn, Felix E. , Verdoorn, Jared T , Benson, John , Mark, Ian , Madhavan, Ajay A , Carr, Carrie M.

The Neuroradiology Journal | March 25, 2024 | Volume: 37 | Issue: 4 | Pages: 468-472

10.1177/19714009241242645 | PMID 38525966 Get It

Background and Purpose Spontaneous intracranial hypotension (SIH) is caused by spinal cerebrospinal fluid (CSF) leaks. This study assessed whether the certainty and/or multifocality of CSF leaks is associated with the severity of intracranial sequelae of SIH. Materials and Methods A retrospective review was completed of patients with suspected SIH that underwent digital subtraction myelogram (DSM) preceded by brain MRI. DSMs were evaluated for the presence or absence of a CSF leak, categorized both as positive/negative/indeterminate and single versus multifocal. Brain MRIs were assessed for intracranial sequelae of SIH based on two probabilistic scoring systems (Dobrocky and Mayo methods). For each system, both an absolute “numerical” score (based on tabulation of findings) and “categorized” score (classification of probability) were tabulated. Results 174 patients were included; 113 (64.9%) were female, average age 52.0 ± 14.3 years. One or more definite leaks were noted in 76 (43.7%) patients; an indeterminate leak was noted in 22 (12.6%) patients. 16 (16.3%) had multiple leaks. There was no significant difference in the severity of intracranial findings between patients with a single versus multiple leaks ( p values ranged from .36 to .70 using categorized scores and 0.22–0.99 for numerical scores). Definite leaks were more likely to have both higher categorized intracranial scores (Mayo p = .0008, Dobrocky p = .006) and numerical scores ( p = .0002 for Mayo and p = .006 for Dobrocky). Conclusions Certainty of a CSF leak on diagnostic imaging is associated with severity of intracranial sequelae of SIH, with definite leaks having significantly more intracranial findings than indeterminate leaks. Multifocal leaks do not cause greater intracranial abnormalities.
Intrathecal hematoma following epidural blood patch: An alternative mechanism to intrathecal puncture
Mark, Ian T. , Madhavan, Ajay A. , Cutsforth‐Gregory, Jeremy K. , Mark, Ian , Madhavan, Ajay A , Carr, Carrie, Cutsforth-Gregory, Jeremy K , Carr, Carrie M.

The Neuroradiology Journal | March 23, 2024 | Volume: 38 | Issue: 1 | Pages: 121-123

10.1177/19714009241242587 | PMID 38520266 Get It

Intrathecal blood after a percutaneous epidural blood patch is a known complication, one that has been previously attributed to inadvertent needle tip position in the subarachnoid space. We present two cases with imaging confirmation of an alternative mechanism, one that includes blood transferring from the epidural space to the subarachnoid space through a pre-existing dural defect.