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18 citation(s) found for "Kelly, Michael".

Abstract W MP34: Safety and Efficacy of Hydrosoft Coils in the Treatment of the Aneurysm Neck: Preliminary Results From the GEL THE NEC Registry
Brinjikji, Waleed , Connelly, Beth B, Tubman, D, Jensen, Mary E. , Chaudry, I, Kallmes, David F. , Hoh, Brian L. , Kelly, Michael , Jabbour, Pascal , Hui, Ferdinand

Mayo Clinic

Stroke | March 20, 2022 | Volume: 45 | Issue: suppl_1 | Pages: No page available

10.1161/str.45.suppl_1.wmp34 Get It

Background and Purpose: The HydroSoft coil was developed to be placed along the aneurysm neck to enhance intracranial aneurysm healing. In order to better understand the safety and efficacy of Hydrosoft coils in treating the aneurysm neck, the GEL THE NEC multicenter registry was developed. We report immediate angiographic and clinical results of this prospective registry. Methods: The GEL THE NEC study was undertaken at 30 centers in 5 countries. Patients aged 21-90 years with a ruptured or unruptured aneurysm 3-15 mm in size were eligible for enrollment. For each patient the following data were obtained: demographics and comorbidities, aneurysm geometry, use of adjunctive devices, immediate angiographic outcomes, and early (<30 days) adverse events. Postoperative anatomic results were graded by on-site neuroradiologists using the Modified Raymond Scale (Raymond 1=complete obliteration of aneurysm including the neck, Raymond 2=contrast filling the neck of the aneurysm without opacification of the aneurysm sac, Raymond 3=contrast filling the sac of the aneurysm). Predictors of good angiographic outcome were studied using chi-squared and t-tests. Results: A total of 571 patients with 571 aneurysms have been treated thus far in the study (196 ruptured, 375 unruptured). HydroSoft coils were successfully deployed in 549 (96.3%) of these patients. Adjunctive devices were used in 307 cases (53.8%) (212 balloon assistance, 89 stent). Aneurysmal occlusion rates were the following: 261 patients (47.3%) exhibited Raymond 1 occlusion, 257 patients (47.0%) had Raymond 2, and 29 patients (5.3%) had Raymond 3. Early post-operative stroke occurred in 10 patients (1.8%). Aneurysm perforation occurred in 11 patients (1.9%). Coil prolapse/migration occurred in 8 patients (1.4%). Early post-operative death occurred in 3 patients, all of whom presented with SAH (0.5%). Small aneurysm neck size was a significant predictor of good angiographic outcome (P=0.0003). Conclusions: Endovascular treatment of intracranial aneurysms with HydroSoft coils resulted in high rates of satisfactory occlusion (94.3%) and low rates of major clinical complications. Aneurysm neck size was a significant predictor of angiographic outcomes.
Occipital-Cervical Fusion and Ventral Decompression in the Surgical Management of Chiari-1 Malformation and Syringomyelia: Analysis of Data From the Park-Reeves Syringomyelia Research Consortium
CreveCoeur, Travis S. , Yahanda, Alexander T. , Maher, Cormac O. , Johnson, Gabrielle W. , Ackerman, Laurie L. , Adelson, P. David , Albert, Gregory W. , Aldana, Phillipp R, Alden, Tord D. , Anderson, Richard C. E. , Baird, Lissa , Bauer, David F. , Bierbrauer, Karin S. , Brockmeyer, Douglas L. , Chern, Joshua J. , Couture, Daniel E., Daniels, David, Dauser, Robert C., Durham, Susan, Ellenbogen, Richard G. , Eskandari, Ramin , Fuchs, Herbert E., George, Timothy M., Greene, Stephanie , Gross, Naina L. , Guillaume, Daniel, Hankinson, Todd C. , Heuer, Gregory G. , Iantosca, Mark, Iskandar, Bermans J. , Jackson, Eric M. , Jea, Andrew, Johnston, James M. , Keating, Robert F., Kelly, Michael P. , Khan, Nickalus R. , Krieger, Mark D., Leonard, Jeffrey R. , Mangano, Francesco T. , Mapstone, Timothy B., McComb, J. Gordon , Muhlbauer, Michael S., Oakes, W. Jerry, Olavarria, Greg, O’Neill, Brent R., Park, Tae Sung, Ragheb, John , Shannon, Chevis N. , Smith, Jodi L. , Stone, Scellig , Strahle, Jennifer M. , Tamber, Mandeep S. , Torner, James C., Tuite, Gerald F. , Wait, Scott D. , Wellons, John C. , Whitehead, William E. , Limbrick, David D. , Torner, James C. , Kelly, Michael P , Yahanda, Alexander T , Ahmed, Raheel , Aldana, Phillip R., Grant, Gerald A. , Graupman, Patrick C. , Greenfield, Jeffrey P. , Guillaume, Daniel J, Haller, Gabe , Menezes, Arnold H. , Selden, Nathan R. W. , Shah, Manish N. , Shimony, Joshua S. , Limbrick, David D.

Mayo Clinic

Neurosurgery | September 22, 2020 | Volume: 88 | Issue: 2 | Pages: 332-341

10.1093/neuros/nyaa460 | PMID 33313928 Get It

Abstract BACKGROUND Occipital-cervical fusion (OCF) and ventral decompression (VD) may be used in the treatment of pediatric Chiari-1 malformation (CM-1) with syringomyelia (SM) as adjuncts to posterior fossa decompression (PFD) for complex craniovertebral junction pathology. OBJECTIVE To examine factors influencing the use of OCF and OCF/VD in a multicenter cohort of pediatric CM-1 and SM subjects treated with PFD. METHODS The Park-Reeves Syringomyelia Research Consortium registry was used to examine 637 subjects with cerebellar tonsillar ectopia ≥ 5 mm, syrinx diameter ≥ 3 mm, and at least 1 yr of follow-up after their index PFD. Comparisons were made between subjects who received PFD alone and those with PFD + OCF or PFD + OCF/VD. RESULTS All 637 patients underwent PFD, 505 (79.2%) with and 132 (20.8%) without duraplasty. A total of 12 subjects went on to have OCF at some point in their management (PFD + OCF), whereas 4 had OCF and VD (PFD + OCF/VD). Of those with complete data, a history of platybasia (3/10, P = .011), Klippel-Feil (2/10, P = .015), and basilar invagination (3/12, P < .001) were increased within the OCF group, whereas only basilar invagination (1/4, P < .001) was increased in the OCF/VD group. Clivo-axial angle (CXA) was significantly lower for both OCF (128.8 ± 15.3°, P = .008) and OCF/VD (115.0 ± 11.6°, P = .025) groups when compared to PFD-only group (145.3 ± 12.7°). pB-C2 did not differ among groups. CONCLUSION Although PFD alone is adequate for treating the vast majority of CM-1/SM patients, OCF or OCF/VD may be occasionally utilized. Cranial base and spine pathologies and CXA may provide insight into the need for OCF and/or OCF/VD.
The Hydrogel Endovascular Aneurysm Treatment Trial (HEAT): A Randomized Controlled Trial of the Second-Generation Hydrogel Coil
Bendok, Bernard R. , Abi-Aad, Karl R., Ward, Jennifer , Kniss, Jason F , Kwasny, Mary , Rahme, Rudy J. , Aoun, Salah G. , Tecle, Najib E. El , Zammar, Samer G. , Aoun, Rami James N. , Patra, Devi Prasad, Raymond, Jean , Woo, Henry H. , Dabus, Guilherme , Milot, Geneviève , Scott, John A. , DeNardo, Andrew , Investigators, HEAT Study, Lavine, Sean D., Bozorgchami, Hormozd, Veznedaroglu, Erol, Albuquerque, Felipe C. , Fiorella, David, Boulos, Alan S. , Cortes, Maria, Kanaan, Hilal, Jindal, Gaurav , Klucznik, Richard , Kalmes, David, Xavier, Andrew, Hussain, Muhammad , Moran, Christopher J. , Adel, Brian van , Milot, Genevieve, Hirsch, Joshua A , Carpenter, Jeffrey , Powers, Ciarán J. , Luh, George, Tummala, Ramanchandra, Evans, Avery J. , Garg, Ankur, James, Roberts, Sauvageau, Eric , Fields, Jeremy D. , Grobelny, Thomas, Hartman, J., Patra, Devi P. , Bendok, Bernard R , Ward, Jennifer D, Ahmadieh, Tarek Y. El , Ansari, Sameer A. , Fiorella, David , Dabus, Guilherme C. , Almandoz, Josser E Delgado , Dashti, Shervin R , Investigators, HEAT Study, Deshaies, Eric Michael , Fiorella, David, Tawk, Rabih G. , Romero, Charles, Kelly, Michael , Chaudry, Imran , Pandey, Aditya S , Wang, Dennis Y.Q. , Milot, Genevieve, Jabbour, Pascal , Shankar, Jai , Patsalides, Athos T , Lee, Sung , James, Robert F. , Jayaraman, Mahesh V. , Satti, Sudhakar R

Mayo Clinic

Neurosurgery | February 10, 2020 | Volume: 86 | Issue: 5 | Pages: 615-624

10.1093/neuros/nyaa006 | PMID 32078692 Get It

Abstract BACKGROUND Aneurysm recurrence after coiling has been associated with aneurysm growth, (re)hemorrhage, and a greater need for follow-up. The second-generation HydroCoil Embolic System (HES; MicroVention, Inc) consists of a platinum core with integrated hydrogel and was developed to reduce recurrence through enhancing packing density and healing within the aneurysm. OBJECTIVE To compare recurrence between the second-generation HES and bare platinum coil (BPC) in the new-generation Hydrogel Endovascular Aneurysm Treatment Trial (HEAT). METHODS HEAT is a randomized, controlled trial that enrolled subjects with ruptured or unruptured 3- to 14-mm intracranial aneurysms amenable to coiling. The primary endpoint was aneurysm recurrence using the Raymond-Roy scale. Secondary endpoints included minor and major recurrence, packing density, adverse events related to the procedure and/or device, mortality, initial complete occlusion, aneurysm retreatment, hemorrhage from target aneurysm during follow-up, aneurysm occlusion stability, and clinical outcome at final follow-up. RESULTS A total of 600 patients were randomized (HES, n = 297 and BPC, n = 303), including 28% with ruptured aneurysms. Recurrence occurred in 11 (4.4%) subjects in the HES arm and 44 (15.4%) subjects in the BPC arm ( P = .002). While the initial occlusion rate was higher with BPC, the packing density and both major and minor recurrence rates were in favor of HES. Secondary endpoints including adverse events, retreatment, hemorrhage, mortality, and clinical outcome did not differ between arms. CONCLUSION Coiling of small-to-medium aneurysms with second-generation HES resulted in less recurrence when compared to BPC, without increased harm. These data further support the use of the second-generation HES for the embolization of intracranial aneurysms. Video Abstract
Radiological and clinical predictors of scoliosis in patients with Chiari malformation type I and spinal cord syrinx from the Park-Reeves Syringomyelia Research Consortium
Strahle, Jennifer M. , Taiwo, Rukayat , Averill, Christine, Torner, James C., Shannon, Chevis N. , Bonfield, Christopher M. , Tuite, Gerald F. , Bethel-Anderson, Tammy, Rutlin, Jerrel, Brockmeyer, Douglas L. , Wellons, John C. , Leonard, Jeffrey R. , Mangano, Francesco T. , Johnston, James M. , Iskandar, Bermans J. , Tyler‐Kabara, Elizabeth C. , Jackson, Eric M. , Couture, Daniel E., Adelson, P. David , Alden, Tord D. , Aldana, Philipp R. , Anderson, Richard C. E. , Baird, Lissa , Bierbrauer, Karin S. , Chern, Joshua J. , Whitehead, William E. , Ellenbogen, Richard G. , Fuchs, Herbert E., Guillaume, Daniel, Hankinson, Todd C. , Iantosca, Mark, Oakes, W. Jerry, Keating, Robert F., Khan, Nickalus R. , Muhlbauer, Michael S., McComb, J. Gordon , Menezes, Arnold H. , Ragheb, John , Smith, Jodi L. , Maher, Cormac O. , Greene, Stephanie , Kelly, Michael P. , O’Neill, Brent R., Krieger, Mark D., Tamber, Mandeep S. , Durham, Susan, Olavarria, Greg, Stone, Scellig , Kaufman, Bruce A., Heuer, Gregory G. , Bauer, David F. , Albert, Gregory W. , Greenfield, Jeffrey P. , Wait, Scott D. , Poppel, Mark D Van, Eskandari, Ramin , Mapstone, Timothy B., Dacey, Ralph G. , Park, Tae Sung, Limbrick, David D. , Torner, James C. , Kelly, Michael P , Shah, Manish N. , Daniels, David J. , Grant, Gerald A. , Selden, Nathan R. W. , Guillaume, Daniel J., Shimony, Joshua S. , Limbrick, David D.

Mayo Clinic

Journal of Neurosurgery: Pediatrics | October 19, 2019 | Volume: 24 | Issue: 5 | Pages: 520-527

10.3171/2019.5.peds18527 | PMID 31419800 Get It

OBJECTIVEScoliosis is frequently a presenting sign of Chiari malformation type I (CM-I) with syrinx. The authors’ goal was to define scoliosis in this population and describe how radiological characteristics of CM-I and syrinx relate to the presence and severity of scoliosis.METHODSA large multicenter retrospective and prospective registry of pediatric patients with CM-I (tonsils ≥ 5 mm below the foramen magnum) and syrinx (≥ 3 mm in axial width) was reviewed for clinical and radiological characteristics of CM-I, syrinx, and scoliosis (coronal curve ≥ 10°).RESULTSBased on available imaging of patients with CM-I and syrinx, 260 of 825 patients (31%) had a clear diagnosis of scoliosis based on radiographs or coronal MRI. Forty-nine patients (5.9%) did not have scoliosis, and in 516 (63%) patients, a clear determination of the presence or absence of scoliosis could not be made. Comparison of patients with and those without a definite scoliosis diagnosis indicated that scoliosis was associated with wider syrinxes (8.7 vs 6.3 mm, OR 1.25, p < 0.001), longer syrinxes (10.3 vs 6.2 levels, OR 1.18, p < 0.001), syrinxes with their rostral extent located in the cervical spine (94% vs 80%, OR 3.91, p = 0.001), and holocord syrinxes (50% vs 16%, OR 5.61, p < 0.001). Multivariable regression analysis revealed syrinx length and the presence of holocord syrinx to be independent predictors of scoliosis in this patient cohort. Scoliosis was not associated with sex, age at CM-I diagnosis, tonsil position, pB–C2 distance (measured perpendicular distance from the ventral dura to a line drawn from the basion to the posterior-inferior aspect of C2), clivoaxial angle, or frontal-occipital horn ratio. Average curve magnitude was 29.9°, and 37.7% of patients had a left thoracic curve. Older age at CM-I or syrinx diagnosis (p < 0.0001) was associated with greater curve magnitude whereas there was no association between syrinx dimensions and curve magnitude.CONCLUSIONSSyrinx characteristics, but not tonsil position, were related to the presence of scoliosis in patients with CM-I, and there was an independent association of syrinx length and holocord syrinx with scoliosis. Further study is needed to evaluate the nature of the relationship between syrinx and scoliosis in patients with CM-I.
Esophageal Perforation Following Anterior Cervical Spine Surgery: Case Report and Review of the Literature
Hershman, Stuart H. , Kunkle, William Aaron , Kelly, Michael P. , Ray, Wilson Z. , Bumpass, David B. , Peters, Colleen , Smith, Zachary A. , Hsu, Wellington K. , Currier, Bradford L. , Rahman, RaʼKerry K., Isaacs, Robert E., Smith, Justin S. , Shaffrey, Christopher I. , Thompson, Sara E., Wang, Jeffrey C. , Lord, Elizabeth L. , Buser, Zorica , Fehlings, Michael G. , Mroz, Thomas E., Buchowski, Jacob M. , Gum, Jeffrey L. , Singhatanadgige, Weerasak , Kim, Jin Young , Nassr, Ahmad , Arnold, Paul M. , Mroz, Thomas E. , Riew, Kiehyun Daniel , Fehlings, Michael G , Kelly, Michael P

Mayo Clinic

Global Spine Journal | April 19, 2017 | Volume: 7 | Issue: 1_suppl | Pages: 28S-36S

10.1177/2192568216687535 | PMID 28451488 Get It

Study Design: Multicenter retrospective case series and review of the literature. Objective: To determine the rate of esophageal perforations following anterior cervical spine surgery. Methods: As part of an AOSpine series on rare complications, a retrospective cohort study was conducted among 21 high-volume surgical centers to identify esophageal perforations following anterior cervical spine surgery. Staff at each center abstracted data from patients’ charts and created case report forms for each event identified. Case report forms were then sent to the AOSpine North America Clinical Research Network Methodological Core for data processing and analysis. Results: The records of 9591 patients who underwent anterior cervical spine surgery were reviewed. Two (0.02%) were found to have esophageal perforations following anterior cervical spine surgery. Both cases were detected and treated in the acute postoperative period. One patient was successfully treated with primary repair and debridement. One patient underwent multiple debridement attempts and expired. Conclusions: Esophageal perforation following anterior cervical spine surgery is a relatively rare occurrence. Prompt recognition and treatment of these injuries is critical to minimizing morbidity and mortality.
Ki67 Proliferation Index as a Tool for Chemotherapy Decisions During and After Neoadjuvant Aromatase Inhibitor Treatment of Breast Cancer: Results From the American College of Surgeons Oncology Group Z1031 Trial (Alliance)
Gonçalves, Rodrigo , Sanati, Souzan , Creighton, Chad J. , DeSchryver, Katherine, Crouch, Erika C., Brink, Amy, Luo, Jingqin , Yu, Tao , Budd, G. Thomas , Silverman, Paula , Esserman, Laura J. , Cynthia, X. , Unzeitig, Gary, Whitworth, Pat W. , Babiera, Gildy V., Guenther, J. Michael, Dayao, Zoneddy , Ota, David M., Leitch, Marilyn , Allred, D. Craig, Ellis, Matthew J. , Hoog, Jeremy , Crouch, Erika, Barnes, Michael, Dowsett, Mitchell, Winer, Eric, Esserman, Laura, Carey, Lisa, Ma, Cynthia X., Pluard, Timothy , Whitworth, Pat, Babiera, Gildy, Ota, David, Olson, John A. , Hunt, Kelly, Suman, Vera J. , Watson, Mark A. , Barnes, Michael , Dowsett, Mitch , Winer, Eric P. , Carey, Lisa A. , Hunt, Kelly K. , Esserman, Laura J , Luo, Jingqin

Mayo Clinic

Journal of Clinical Oncology | February 23, 2017 | Volume: 35 | Issue: 10 | Pages: 1061-1069

10.1200/jco.2016.69.4406 | PMID 28045625 Get It

Purpose To determine the pathologic complete response (pCR) rate in estrogen receptor (ER) –positive primary breast cancer triaged to chemotherapy when the protein encoded by the MKI67 gene (Ki67) level was > 10% after 2 to 4 weeks of neoadjuvant aromatase inhibitor (AI) therapy. A second objective was to examine risk of relapse using the Ki67-based Preoperative Endocrine Prognostic Index (PEPI). Methods The American College of Surgeons Oncology Group (ACOSOG) Z1031A trial enrolled postmenopausal women with stage II or III ER-positive (Allred score, 6 to 8) breast cancer whose treatment was randomly assigned to neoadjuvant AI therapy with anastrozole, exemestane, or letrozole. For the trial ACOSOG Z1031B, the protocol was amended to include a tumor Ki67 determination after 2 to 4 weeks of AI. If the Ki67 was > 10%, patients were switched to neoadjuvant chemotherapy. A pCR rate of > 20% was the predefined efficacy threshold. In patients who completed neoadjuvant AI, stratified Cox modeling was used to assess whether time to recurrence differed by PEPI = 0 score (T1 or T2, N0, Ki67 < 2.7%, ER Allred > 2) versus PEPI > 0 disease. Results Only two of the 35 patients in ACOSOG Z1031B who were switched to neoadjuvant chemotherapy experienced a pCR (5.7%; 95% CI, 0.7% to 19.1%). After 5.5 years of median follow-up, four (3.7%) of the 109 patients with a PEPI = 0 score relapsed versus 49 (14.4%) of 341 of patients with PEPI > 0 (recurrence hazard ratio [PEPI = 0 v PEPI > 0], 0.27; P = .014; 95% CI, 0.092 to 0.764). Conclusion Chemotherapy efficacy was lower than expected in ER-positive tumors exhibiting AI-resistant proliferation. The optimal therapy for these patients should be further investigated. For patients with PEPI = 0 disease, the relapse risk over 5 years was only 3.6% without chemotherapy, supporting the study of adjuvant endocrine monotherapy in this group. These Ki67 and PEPI triage approaches are being definitively studied in the ALTERNATE trial (Alternate Approaches for Clinical Stage II or III Estrogen Receptor Positive Breast Cancer Neoadjuvant Treatment in Postmenopausal Women: A Phase III Study; clinical trial information: NCT01953588).
GEL THE NEC: a prospective registry evaluating the safety, ease of use, and efficacy of the HydroSoft coil as a finishing device
Brinjikji, Waleed , Amar, Arun Paul , Almandoz, Josser E Delgado , Díaz, Orlando , Jabbour, Pascal , Kelly, Michael , Layton, Kennith D, Miller, Jeffrey W. , Levy, Elad, Moran, Christopher J. , Woo, Henry H. , Sellar, Robin, Ho, Brian , Evans, Avery J. , Kallmes, David F. , Suh, Dae C , Jabbour, Pascal , Hanel, Ricardó A. , Hui, Ferdinand , Levy, E, Ho, Brian, Miller, Jeffrey

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Journal of NeuroInterventional Surgery | January 30, 2017 | Volume: 10 | Issue: 1 | Pages: 83-87

10.1136/neurintsurg-2016-012915 | PMID 28138062 Get It

Background and purpose The HydroSoft coil was developed as a finishing coil, ideally to be placed along the aneurysm neck to enhance intracranial aneurysm healing. The GEL THE NEC (Gaining Efficacy Long Term: Hydrosoft, an Emerging, New, Embolic Coil) multicenter registry was developed to assess the safety and efficacy of HydroSoft coils in treating intracranial aneurysms. We report angiographic and clinical results of this prospective registry. Materials and methods GEL THE NEC was performed at 27 centers in five countries. Patients aged 21–90 years with a ruptured or unruptured aneurysm 3–15 mm in size were eligible for enrollment. The following variables were obtained: demographics/comorbidities, aneurysm geometry, adjunctive devices used, proportion of patients in whom HydroSoft coils were successfully placed, and long-term angiographic outcomes (graded by an independent core laboratory using the Modified Raymond Scale), and procedure-related adverse events. Predictors of good angiographic outcome were studied using χ2 and t-tests. Results A total of 599 patients with 599 aneurysms were included in this study. HydroSoft coils were successfully deployed in 577 (96.4%) patients. Procedure-related major morbidity and mortality were 0.5% (3/599) and 1.3% (8/599), respectively. The most common perioperative complications were iatrogenic vasospasm (30/599, 5.0%), thromboemboli (27/599, 4.5%), and aneurysm perforation (16/599, 2.7%). At last angiographic follow-up (mean 9.0±6.3 months), the complete occlusion rate was 63.2% (280/442) and near complete occlusion rate was 25.2% (107/442). The core laboratory read recanalization rate was 10.8% (46/425) and the retreatment rate was 3.4% (20/599). Conclusions Endovascular treatment of intracranial aneurysms with HydroSoft coils resulted in complete/near complete occlusion rates of 88% and a major complication rate of 1.8%. Trial registration number NCT01000675.
Histopathological findings following pipeline embolization in a human cerebral aneurysm at the basilar tip
Kelly, Michael , Kadirvel, Ramanathan , Kallmes, David F. , Dai, Daying , Kallmes, David, Ding, Yonghong

Mayo Clinic

Interventional Neuroradiology | February 3, 2016 | Volume: 22 | Issue: 2 | Pages: 153-157

10.1177/1591019915622165 | PMID 26842611 Get It

We report histopathological findings from a human cerebral aneurysm following treatment with a flow diverter. A 75-year-old male underwent flow diversion treatment (Pipeline Embolization Device (PED)) and coil embolization for treatment of an aneurysm at the basilar tip. At four months, angiography showed complete aneurysm occlusion; at 12 months angiography demonstrated that the aneurysm had reopened. The patient expired from brainstem compression. The aneurysm cavity was primarily filled with unorganized thrombus. Thick, interrupted neointima crossed the neck interface indicating blood flow into aneurysm through small channels. Along the parent artery the PED was covered by neointima having a measured thickness of 0.19 ± 0.01 mm; the maximal stenosis of the proximal parent artery was 27%. The perforating arteries that were crossed by the PED remained patent. Findings in this human case are similar to those in the elastase-induced aneurysms in rabbits.