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Dive into the research topics where Kristi Ellen is active.

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Featured researches published by Kristi Ellen.


Gastrointestinal Endoscopy | 2009

Temporary placement of fully covered self-expandable metal stents in benign biliary strictures: midterm evaluation (with video)

Anshu Mahajan; Henry Ho; Bryan G. Sauer; Melissa S. Phillips; Vanessa M. Shami; Kristi Ellen; Michele E. Rehan; Timothy M. Schmitt; Michel Kahaleh

BACKGROUND Benign biliary strictures (BBS) have been endoscopically managed with placement of multiple plastic stents. Uncovered metal stents have been associated with mucosal hyperplasia and partially covered self-expandable metal stents with migration. Recently, fully covered self-expandable metal stents (CSEMSs) with anchoring fins have become available. OBJECTIVE Our purpose was to analyze the efficacy and complication rates of CSEMSs in the treatment of BBS. DESIGN CSEMSs (10-mm diameter) were placed in 44 patients with BBS. CSEMSs were left in place until adequate biliary drainage was achieved, confirmed by resolution of symptoms, normalization of liver function tests, and imaging. SETTING Tertiary care center with long-standing experience with metal stents. PATIENTS A total of 44 patients with BBS (28 men, median age 53.5 years) were included. The preprocedure diagnoses included chronic pancreatitis (n = 19), gallstone-related strictures (n = 14), post liver transplant (n = 9), autoimmune pancreatitis (n = 1), and primary sclerosing cholangitis (n = 1). INTERVENTION ERCP with temporary CSEMS placement. Removal of CSEMSs was performed with a snare or rat tooth. MAIN OUTCOME MEASUREMENTS Stricture resolution and morbidity. RESULTS The median time of CSEMS placement was 3.3 months (interquartile range 3.0-4.8). Resolution of the BBS was confirmed in 34 of 41 patients (83%) after a median postremoval follow-up time of 3.8 months (interquartile range 1.2-7.7). Complications were observed in 6 (14%) patients after CSEMS placement and in 4 (9%) after CSEMS removal. LIMITATION Pilot study from a single center. CONCLUSION Temporary placement of CSEMSs for BBS may offer an alternative to plastic stenting. Further investigation is required to further assess safety and long-term efficacy.


Gastrointestinal Endoscopy | 2008

Transenteric drainage of pancreatic-fluid collections with fully covered self-expanding metallic stents (with video)

Jayant P. Talreja; Vanessa M. Shami; Jennifer Ku; Tanya D. Morris; Kristi Ellen; Michel Kahaleh

BACKGROUND Drainage of pancreatic-fluid collections (PFCs) by using fully covered self-expanding metallic stents (CSEMSs) offers the option of providing a larger-diameter access fistula for drainage when compared with plastic stents. OBJECTIVE To evaluate the efficacy and safety of transenteric drainage of PFCs by using CSEMSs. DESIGN A prospective case series. SETTING A tertiary-referral center. PATIENTS Between January 2007 and September 2007, 18 patients underwent drainage of PFCs by using CSEMSs. Follow-up and final results were prospectively recorded until May 2008. INTERVENTIONS Placement of CSEMSs with a double-pigtail stent placed alongside (4 cases) or into the CSEMS (14 cases) to prevent migration. MAIN OUTCOME MEASUREMENTS The number of sessions and time to resolution of the PFCs. RESULTS A median of 1 session was required to achieve drainage (range 1-4) when using CSEMSs. Complications included superinfection (5), bleeding (2), and inner migration (1). A total of 17 of 18 patients (95%) responded successfully, with 14 patients (78%) achieving complete resolution of their PFC. The mean (+/- SD) time of follow-up until final resolution was 77 +/- 80 days (range 15-310 days). CONCLUSIONS Placement of CSEMSs seems to offer an effective and safe alternative for the drainage of PFCs. A randomized controlled trial should be performed to compare this technique with plastic-stent drainage.


Clinical Gastroenterology and Hepatology | 2008

Unresectable Cholangiocarcinoma: Comparison of Survival in Biliary Stenting Alone Versus Stenting With Photodynamic Therapy

Michel Kahaleh; Rajnish Mishra; Vanessa M. Shami; Patrick G. Northup; Carl L. Berg; Penny Bashlor; Petra Jones; Kristi Ellen; Geoffrey R. Weiss; Christiana M. Brenin; Barbara E. Kurth; Tyvin A. Rich; Reid B. Adams; Paul Yeaton

BACKGROUND & AIMS Photodynamic therapy (PDT) for unresectable cholangiocarcinoma is associated with improvement in cholestasis, quality of life, and potentially survival. We compared survival in patients with unresectable cholangiocarcinoma undergoing endoscopic retrograde cholangiopancreatography (ERCP) with PDT and stent placement with a group undergoing ERCP with stent placement alone. METHODS Forty-eight patients were palliated for unresectable cholangiocarcinoma during a 5-year period. Nineteen were treated with PDT and stents; 29 patients treated with biliary stents alone served as a control group. Multivariate analysis was performed by using Model for End-Stage Liver Disease score, age, treatment by chemotherapy or radiation, and number of ERCP procedures and PDT sessions to detect predictors of survival. RESULTS Kaplan-Meier analysis demonstrated improved survival in the PDT group compared with the stent only group (16.2 vs 7.4 months, P<.004). Mortality in the PDT group at 3, 6, and 12 months was 0%, 16%, and 56%, respectively. The corresponding mortality in the stent group was 28%, 52%, and 82%, respectively. The difference between the 2 groups was significant at 3 months and 6 months but not at 12 months. Only the number of ERCP procedures and number of PDT sessions were significant on multivariate analysis. Adverse events specific to PDT included 3 patients with skin phototoxicity requiring topical therapy only. CONCLUSIONS ERCP with PDT seems to increase survival in patients with unresectable cholangiocarcinoma when compared with ERCP alone. It remains to be proved whether this effect is attributable to PDT or the number of ERCP sessions. A prospective randomized multicenter study is required to confirm these data.


Gastrointestinal Endoscopy | 2009

Single-balloon enteroscopy effectively enables diagnostic and therapeutic retrograde cholangiography in patients with surgically altered anatomy

Andrew Y. Wang; Bryan G. Sauer; Brian W. Behm; Madhuri Ramanath; Dawn G. Cox; Kristi Ellen; Vanessa M. Shami; Michel Kahaleh

BACKGROUND In patients with surgically altered anatomy, ERCP is often unsuccessful. Single-balloon enteroscopy (SBE) enables deep intubation of the small bowel, permitting diagnostic and therapeutic ERCP in this subset of patients. OBJECTIVE To determine the effectiveness of SBE in performing endoscopic retrograde cholangiography (ERC) in patients with surgically altered anatomy. DESIGN Case series. SETTING Large quaternary-care center. PATIENTS Thirteen patients (11 women) underwent 16 SBE procedures with ERCP. Patient anatomy consisted of Whipple (n = 3), hepaticojejunostomy (n = 3), Billroth II (n = 1), and Roux-en-Y (n = 9). INTERVENTIONS Patients with surgically altered anatomy in whom standard ERCP techniques had failed or were not possible underwent ERC by using SBE with initial therapeutic intent. MAIN OUTCOME MEASUREMENTS Success rates of diagnostic ERC and therapeutic ERC in those patients who required biliary intervention. Procedure-related complications were also assessed. RESULTS Diagnostic ERC was successful 12 (92.3%) of 13 patients and in 13 (81.3%) of 16 cases. Therapeutic ERC was required in 10 patients in whom diagnostic ERC was first accomplished, and therapeutic ERC was successful in 9 (90%) of 10 patients. Biliary interventions included balloon dilation (n = 4), stone extraction (n = 2), sphincterotomy (n = 4), removal of a surgically placed stent (n = 3), and stenting (n = 2). Two patients developed pancreatitis after therapeutic ERC. Median follow-up was 53 days (range 22-522 days). Overall procedural success in an intent-to-treat analysis by case was 75%. LIMITATION Single-center experience. CONCLUSION SBE enables diagnostic and therapeutic ERC in most patients with altered anatomy. SBE-assisted therapeutic ERC may be associated with an increased risk of pancreatitis. Improvement of the available equipment is necessary to perform more efficient and effective biliary interventions.


Endoscopy | 2009

Partially covered self-expandable metallic stents for benign biliary strictures due to chronic pancreatitis

B. Behm; Andrew Brock; Bridger W. Clarke; Kristi Ellen; Patrick G. Northup; Jean-Marc Dumonceau; Michel Kahaleh

BACKGROUND AND STUDY AIMS Benign biliary strictures (BBS) may occur in patients with chronic pancreatitis and may lead to secondary biliary cirrhosis or recurrent cholangitis. Although surgical diversion may provide definitive therapy, it can be associated with significant morbidity. Endoscopic therapy with plastic stents has been used as an alternative to surgery but has resulted in unsatisfactory long-term outcomes. We evaluated the temporary placement of partially covered self-expandable metallic stents (PCMS) in patients with BBS due to chronic pancreatitis. PATIENTS AND METHODS A total of 20 patients with BBS due to chronic pancreatitis underwent temporary placement of PCMS over a 6-year period. The primary outcome of interest was the proportion of patients with stricture resolution persisting 6 months after stent removal. Secondary outcomes included the stent failure rate, number of endoscopic sessions required to achieve biliary drainage, total duration of stenting, and complication rate. RESULTS Adequate biliary drainage was achieved in 19 patients with PCMS (95%). Eighteen of the 20 patients (90%) had persistent stricture resolution 6 months after PCMS removal. In two of the 20 patients (10%), PCMS stenting failed and these patients underwent alternative therapies. Complications occurred in four patients (20%). Median duration of PCMS placement was 5 months, requiring a median of two endoscopic procedures. CONCLUSION In this series of patients with BBS due to chronic pancreatitis, temporary PCMS placement achieved persistent stricture resolution in the majority of patients with acceptable complication rates. Comparative trials evaluating temporary PCMS placement and plastic stenting in patients with BBS due to chronic pancreatitis are needed.


Journal of Oncology | 2013

Safety and Efficacy of Radiofrequency Ablation in the Management of Unresectable Bile Duct and Pancreatic Cancer: A Novel Palliation Technique

Paola Figueroa-Barojas; Mihir R. Bakhru; Nagy Habib; Kristi Ellen; Jennifer E. Millman; Armeen Jamal-Kabani; Monica Gaidhane; Michel Kahaleh

Objectives. Radiofrequency ablation (RFA) has replaced photodynamic therapy for premalignant and malignant lesions of the esophagus. However, there is limited experience in the bile duct. The objective of this pilot study was to assess the safety and efficacy of RFA in malignant biliary strictures. Methods: Twenty patients with unresectable malignant biliary strictures underwent RFA with stenting between June 2010 and July 2012. Diameters of the stricture before and after RFA, immediate and 30 day complications and stent patency were recorded prospectively. Results. A total of 25 strictures were treated. Mean stricture length treated was 15.2 mm (SD = 8.7 mm, Range = 3.5–33 mm). Mean stricture diameter before RFA was 1.7 mm (SD = 0.9 mm, Range = 0.5–3.4 mm) while the mean diameter after RFA was 5.2 mm (SD = 2 mm, Range = 2.6–9 mm). There was a significant increase of 3.5 mm (t = 10.8, DF = 24, P value = <.0001) in the bile duct diameter post RFA. Five patients presented with pain after the procedure, but only one developed mild post-ERCP pancreatitis and cholecystitis. Conclusions: Radiofrequency ablation can be a safe palliation option for unresectable malignant biliary strictures. A multicenter randomized controlled trial is required to confirm the long term benefits of RFA and stenting compared to stenting alone.


Endoscopy | 2009

Fully covered self-expandable metallic stents in the management of complex biliary leaks: preliminary data - a case series.

Andrew Y. Wang; Kristi Ellen; Carl L. Berg; Timothy M. Schmitt; Michel Kahaleh

Techniques for management of bile leaks include biliary sphincterotomy and stenting. Partially covered self-expandable metallic stents have been used in complex bile leaks, but they are associated with migration and hyperplasia. A fully covered self-expandable metallic stent (CSEMS) with anchoring fins might be effective in treating bile leaks without these complications. The aim of this study was to investigate the safety and efficacy of temporary placement of a CSEMS for resolving complex bile leaks. Thirteen patients with complex bile leaks underwent endoscopic retrograde cholangiopancreatography (ERCP) with temporary placement of a CSEMS following cholecystectomy (n = 8) or liver transplantation (n = 5). All patients had resolution of their bile leaks. Two patients developed a stricture below the confluence. Three patients died from unrelated causes. Two deaths occurred prior to CSEMS removal. Ten of 11 patients had evidence of biliary debris at the time of CSEMS removal. Overall, temporary placement of CSEMS is efficacious atresolving bile leaks. CSEMS are less prone to migration, but are associated with ulcerations, de novo choledocholithiasis, and strictures.


Gastrointestinal Endoscopy | 2008

Temporary placement of a fully covered self-expandable metal stent in the pancreatic duct for management of symptomatic refractory chronic pancreatitis: preliminary data (with videos)

Bryan G. Sauer; Jayant P. Talreja; Kristi Ellen; Jennifer Ku; Vanessa M. Shami; Michel Kahaleh

BACKGROUND Pancreatic duct (PD) stenting is beneficial for the treatment of pain in patients with PD strictures associated with chronic pancreatitis. Placement of metal stents has been reported but failed secondary to hyperplasia or migration. OBJECTIVE To investigate the outcome of patients with symptomatic and refractory PD strictures who had temporary placement of a covered self-expandable metal stent (CSEMS). DESIGN Patients with refractory PD strictures were offered temporary CSEMS placement. Pain scores were evaluated before and after CSEMS placement. SETTING A tertiary-care center. PATIENTS Six patients (4 men, mean age +/- SD 55 +/- 8 years) received a CSEMS, and 5 patients had removal of a CSEMS after a mean time of 92 days. INTERVENTION Placement of CSEMS (8-mm or 10-mm diameter VIABIL) in the PD, with removal after 3 months. MAIN OUTCOME MEASUREMENTS The pain score before and after stent placement and the sustained response after removal. Morbidity associated with stent placement and removal was also noted. RESULTS Pain scores after CSEMS placement significantly improved (P = .024), from 6.4 to 1.6. Of the 5 patients who underwent CSEMS removal, 3 developed recurrent symptomatic pancreatic stricture, of whom 2 required repeat stenting with a larger-diameter CSEMS (10 mm) and 2 remained pain free. The CSEMS was not removed in 1 patient because pancreatic malignancy was diagnosed. There were no complications during placement or removal of CSEMSs. LIMITATION This was a pilot study. CONCLUSION Temporary placement of CSEMSs in patients with symptomatic refractory PD stricture offers transient relief of pain. Further investigation is needed to determine the optimal diameter and duration of placement.


Gastroenterology Research and Practice | 2012

Endoscopic Ultrasound-Guided Radiofrequency Ablation (EUS-RFA) of the Pancreas in a Porcine Model

Monica Gaidhane; Ioana Smith; Kristi Ellen; Jeremy J. Gatesman; Nagy Habib; Patricia L. Foley; Christopher A. Moskaluk; Michel Kahaleh

Backgrounds. Limited effective palliative treatments exist for pancreatic cancer which includes surgery or chemotherapy. Radiofrequency ablation (RFA) uses high frequency alternating current to ablate diseased tissue and has been used to treat various tumors. In this study, we evaluated a prototype probe adjusted to the EUS-needle to perform EUS-RFA to permit coagulative necrosis in the pancreas. Methods. Five Yucatan pigs underwent EUS-guided radiofrequency ablation of the head of their pancreas. Using an EUS-needle, RFA was applied with 6 mm and then 10 mm of the probe exposed at specific wattage for preset durations. Results. Only one pig showed moderate levels of pancreatitis (20% proximal pancreatitis). The other animals showed much lower areas of tissue damage. In 3 of the 5 pigs, the proximal pancreas showed greater levels of tissue injury than the distal pancreas, consistent with the proximity of the tissue to the procedure site. In 1 pig, both proximal and distal pancreas showed minimal pancreatitis (1%). There was minimal evidence of fat necrosis in intra-pancreatic and/or extra-pancreatic adipose tissue. Conclusion. EUS-guided RFA of the pancreatic head with the monopolar probe through a 19-gauge needle was well tolerated in 5 Yucatan pigs and with minimal amount of pancreatitis.


Digestive and Liver Disease | 2013

Multimodality endoscopic treatment of pancreatic duct disruption with stenting and pseudocyst drainage: How efficacious is it?

Charles W. Shrode; Patrick MacDonough; Monica Gaidhane; Patrick G. Northup; Bryan G. Sauer; Jennifer Ku; Kristi Ellen; Vanessa M. Shami; Michel Kahaleh

BACKGROUND Few studies have described the role of multimodality therapy and the complexity of endoscopic management of pancreatic duct disruption. Our study aim was to analyse and confirm factors associated with the resolution of pancreatic duct disruption. METHODS Over 6 years, retrospective data on patients with pancreatic duct disruption managed endoscopically were retrieved. Success was defined as resolution of the pancreatic duct disruption at 12 months. Logistic regression analysis was performed to determine factors associated with resolution. RESULTS 113 patients (78 male) with a mean age 51.3 year were included. Resolution of the pancreatic duct leak occurred in 80 cases (70.2%). 72 cases received transpapillary pancreatic duct stents, with 51 demonstrating resolution of pancreatic duct leak (71%) cystenterostomy was performed in 68 patients with 51 resolved (75%). In partial duct disruptions, pancreatic duct stenting combined with endoscopic drainage of fluid collections resulted in an increased rate of resolution (80%) compared to complete disruptions treated in a similar manner (57%). In complete pancreatic ductal disruptions, transpapillary pancreatic duct stenting had no additional benefit (9/17, 52.9%) compared to cystenterostomy or percutaneous drainage alone (24/34, 70.6%; P=0.61). CONCLUSION Pancreatic duct disruptions require multimodality treatment, addressing not only the integrity of the pancreatic duct but also any fluid collections associated. Partial ductal disruption should be managed by a bridging stent.

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Michele E. Rehan

University of Virginia Health System

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Melissa S. Phillips

University of Virginia Health System

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Henry C. Ho

University of Virginia Health System

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