J. Karp
Northwestern University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by J. Karp.
Journal of Hepatology | 2014
Laura Kulik; Michael Vouche; Sean W.P. Koppe; Robert J. Lewandowski; Mary F. Mulcahy; Daniel Ganger; Ali Habib; J. Karp; Patrice Al-Saden; Mario E. Lacouture; Jonathan Cotliar; Michael Abecassis; Talia Baker; Riad Salem
BACKGROUND & AIMS To investigate the safety and adverse event profile of sorafenib plus radioembolization (Y90) compared to Y90 alone in patients awaiting liver transplantation. METHODS 20 patients with HCC were randomized to Y90 alone (Group A) or Y90+sorafenib (Group B). Adverse events, dose reductions, and peri-transplant complications were assessed. RESULTS All patients in the sorafenib group necessitated dose reductions. Seventeen of 20 patients underwent liver transplantation; median time-to-transplant was 7.8 months (range: 4.2-20.3) and similar between groups (p = 0.35). In the sorafenib group, there were 4/8 peri-transplant (<30 days) biliary complications (p = 0.029) and 3/8 acute rejections (p = 0.082); there were none in the Y90-only group. Survival rates were 70% (Group A) and 72% (Group B) at 3 years (p = 0.57). CONCLUSIONS The addition of sorafenib to Y90 necessitated dose reductions in all patients awaiting transplantation. Preliminary data suggest that the combination was associated with more peri-transplant biliary complications and potentially trended towards more acute rejections. Caution should be exercised when considering sorafenib in the transplant setting. Further investigation is warranted.
Academic Radiology | 2012
Ryan B. Perumpail; Josh Levitsky; Yi Wang; Victoria S. Lee; J. Karp; Ning Jin; Guang Yu Yang; Bradley D. Bolster; Saurabh Shah; Sven Zuehlsdorff; Albert A. Nemcek; Andrew C. Larson; Frank H. Miller; Reed A. Omary
RATIONALE AND OBJECTIVES Magnetic resonance elastography (MRE) can noninvasively measure the stiffness of liver tissue and display this information in anatomic maps. Magnetic resonance imaging (MRI) guidance has not previously been used to biopsy segments of heterogeneous stiffness identified on MRE. Dedicated study of MRE in post-liver transplant patients is also limited. In this study, the ability of real-time MRI to guide biopsies of segments of the liver with different MRE stiffness values in the same post-transplant patient was assessed. MATERIALS AND METHODS MRE was performed in 9 consecutive posttransplant patients with history of hepatitis C. Segments of highest and lower stiffness on MRE served as targets for subsequent real-time MRI-guided biopsy using T2-weighted imaging. The ability of MRI-guided biopsy to successfully obtain tissue specimens was assessed. The Wilcoxon signed-rank test was used to compare mean stiffness differences for highest and lower MRE stiffness segments, with α = 0.05. RESULTS MRI guidance allowed successful sampling of liver tissue for all (18/18) biopsies. There was a statistically significant difference in mean MRE stiffness values between highest (4.61 ± 1.99 kPa) and lower stiffness (3.03 ± 1.75 kPa) (P = .0039) segments biopsied in the 9 posttransplant patients. CONCLUSION Real-time MRI can guide biopsy in patients after liver transplantation based on MRE stiffness values. This study supports the use of MRI guidance to sample tissue based on functional information.
Journal of Vascular and Interventional Radiology | 2013
A.C. Eifler; Robert J. Lewandowski; Ramona Gupta; J. Karp; Riad Salem; Jungwha Lee; Robert K. Ryu
PURPOSE To test the hypothesis that patient parameters identifiable at the time of inferior vena cava (IVC) filter placement can be used to predict the need for a permanent versus optional filter. MATERIALS AND METHODS A comprehensive institutional database of details and patient parameters for all optional IVC filters placed at a single institution between December 2008 and July 2011 was reviewed. IVC filters were categorized as removed if removal was attempted or as kept permanent if not. Patient parameters (age, sex, history of venous thromboembolism [VTE], presence of neurologic disease or malignancy, indication for filter placement) were compared between groups by multiple logistic regression analysis, and a prediction model based on these parameters was constructed. RESULTS A total of 265 optional IVC filters were placed and analyzed; 167 were removed and 98 were kept permanent. In the multivariable model predicting filter disposition, significant factors associated with permanence were age (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.01-1.05), male sex (OR, 3.01; 95% CI, 1.64-5.54), underlying malignancy (OR, 3.27; 95% CI, 1.77-6.03), and an indication of anticoagulation failure (OR, 8.12; 95% CI, 1.83-36.0). Significant factors associated with removal were history of VTE (OR, 0.39; 95% CI, 0.21-0.74), prophylactic filter placement indication (OR, 0.14; 95% CI, 0.04-0.43), and high-risk VTE (OR, 0.37; 95% CI, 0.15-0.94). The c-statistic for the prediction model based on these parameters was 0.80. CONCLUSIONS Patient parameters can be used to quantitatively predict an optional IVC filter being kept permanent. These findings can aid in optimization of prospective decision-making in IVC filter placement.
Journal of Vascular and Interventional Radiology | 2015
Robert K. Ryu; Kush Desai; J. Karp; Ramona Gupta; Alan Emerson Evans; Shankar Rajeswaran; Riad Salem; Robert J. Lewandowski
PURPOSE To compare the retrievability of 2 potentially retrievable inferior vena cava filter devices. MATERIALS AND METHODS A retrospective, institutional review board-approved study of Celect (Cook, Inc, Bloomington, Indiana) and Option (Rex Medical, Conshohocken, Pennsylvania) filters was conducted over a 33-month period at a single institution. Fluoroscopy time, significant filter tilt, use of adjunctive retrieval technique, and strut perforation in the inferior vena cava were recorded on retrieval. Fisher exact test and Mann-Whitney-Wilcoxon test were used for comparison. RESULTS There were 99 Celect and 86 Option filters deployed. After an average of 2.09 months (range, 0.3-7.6 mo) and 1.94 months (range, 0.47-9.13 mo), respectively, 59% (n = 58) of patients with Celect filters and 74.7% (n = 65) of patients with Option filters presented for filter retrieval. Retrieval failure rates were 3.4% for Celect filters versus 7.7% for Option filters (P = .45). Median fluoroscopy retrieval times were 4.25 minutes for Celect filters versus 6 minutes for Option filters (P = .006). Adjunctive retrieval techniques were used in 5.4% of Celect filter retrievals versus 18.3% of Option filter retrievals (P = .045). The incidence of significant tilting was 8.9% for Celect filters versus 16.7% for Option filters (P = .27). The incidence of strut perforation was 43% for Celect filters versus 0% for Option filters (P < .0001). CONCLUSIONS Retrieval rates for the Celect and Option filters were not significantly different. However, retrieval of the Option filter required a significantly increased amount of fluoroscopy time compared with the Celect filter, and there was a significantly greater usage of adjunctive retrieval techniques for the Option filter. The Celect filter had a significantly higher rate of strut perforation.
Circulation-cardiovascular Interventions | 2017
Kush Desai; James L. Laws; Riad Salem; S. Mouli; M Errea; J. Karp; Yihe Yang; Robert K. Ryu; Robert J. Lewandowski
Background— Despite growth in placement of retrievable inferior vena cava filters, retrieval rates remain low. Filters with extended implantation times present a challenge to retrieval, where standard techniques often fail. The development of advanced retrieval techniques has positively impacted retrieval of retrievable inferior vena cava filters with prolonged dwell times; however, there is no precise definition of the time point when advanced techniques become necessary. We aim to define prolonged retrievable inferior vena cava filters dwell time by determining the inflection point when the risk of standard retrieval technique failure increases significantly, necessitating advanced retrieval techniques to maintain overall technical success of retrieval. Methods and Results— From January 2009 to April 2015, 762 retrieval procedures were identified from a prospectively acquired database. We assessed patient age/sex, filter dwell time, procedural technical success, the use of advanced techniques, and procedure-related adverse events. Overall retrieval success rate was 98% (n=745). When standard retrieval techniques failed, advanced techniques were used; this was necessary 18% of the time (n=138). Logistic regression identified that dwell time was the only risk factor for failure of standard retrieval technique (odds ratio, 1.08; 95% confidence interval, 1.05–1.10; P<0.001). Spline function regression analysis demonstrated that if dwell time exceeded 7 months, the risk of standard technique failure was 40.9%. Adverse events occurred at a rate of 2% (n=18; 15 minor and 3 major). Conclusions— The necessity of advanced techniques to maintain technical success of retrieval increases with dwell time. Patients with retrievable inferior vena cava filters in place beyond 7 months may benefit from referral to centers with expertise in advanced filter retrieval.
Urology | 2018
Riad Salem; John Hairston; Elias Hohlastos; Ahsun Riaz; Joseph Ralph Kallini; Ahmed Gabr; Rehan Ali; Kimberly Jenkins; J. Karp; Kush Desai; Bartley Thornburg; David D. Casalino; Frank H. Miller; Matthias D. Hofer; Nabeel Hamoui; S. Mouli
OBJECTIVE To evaluate the safety and efficacy of prostate artery embolization (PAE) for lower urinary tract symptoms (LUTS) attributed to benign prostatic hyperplasia (BPH). METHODS A prospective, single-center, open-label FDA-approved study was conducted to evaluate the safety and efficacy of PAE for LUTS secondary to BPH. We enrolled men ≥ 45, prostate volume > 40 g, International prostate symptom score (IPSS) > 13, peak flow rate (Qmax) ≤ 12 mL/s, and voided volume ≥ 125 mL. Patients were evaluated with questionnaires (IPSS, quality-of-life [QoL], International index of erectile function, and male sexual health questionnaire for ejaculatory dysfunction) and clinical measures (postvoid residual volume and Qmax at baseline 1, 3, and 12 months) after PAE. Baseline and 6-month total prostate (TV) and central gland (CG) volumes were obtained. RESULTS 45 patients (mean volume: 99 cc, range: 30-214 g) were treated over the course of the 3-year study. At 1 month, there were improvements in IPSS (23.6 ± 6.1 to 12.0 ± 5.9, P < .0001), QoL (4.8 ± 0.9 to 2.6 ± 1.6, P < .0001), Qmax (5.8 ± 1.0 to 12.4 ± 6.8,P < .0001). At 3 months, there were improvements in IPSS (10.2 ± 6.0, P < .0001), QoL (2.4 ± 1.6, P < .0001) and Qmax (15.3 ± 12.3, P < .0001). At 6 months, there were improvements in IPSS (11.0 ± 7.6, P < .0001) and QoL (2.3 ± 1.7, P < .0001). At 1 year, there were improvements in IPSS (12.4 ± 8.4,P < .0001) and QoL (2.6 ± 1.6, P < .0001). There were reductions in postvoid volume residues: baseline 157 ± 45, 1 month 123 ± 47, P = .057, 3 months 127 ± 114, P = .34, 6 months 112±116, P = .002 and 1 year 109±116 P = .025. Median decreases in TV and CG were 18% (CI: 13-27) (P = 0.0001) and 27% (CI: 20-36)(P = 0.0001), respectively. Self-limited adverse events included dysuria (n = 13), hematuria (n = 6), hematospermia (n = 2), urinary frequency (n = 3) and retention (n = 2). No severe adverse events, nontarget embolization, or adverse effects on erectile function or sexual health. CONCLUSION This prospective clinical trial demonstrates that PAE is safe and efficacious for BPH, with significant improvement in LUTS and reduction in TV and CG volumes.
Journal of clinical and diagnostic research : JCDR | 2015
Sabeen Dhand; S. David Stulberg; Lalit Puri; J. Karp; Robert K. Ryu; Robert J. Lewandowski
INTRODUCTION Some patients undergoing total joint arthroplasty are at increased risk for venous thromboembolism (VTE). The aim of the present study was to evaluate the safety and efficacy of prIVCF in preventing PE in patients undergoing joint replacement surgery who are at high-risk for VTE. MATERIALS AND METHODS In this prospective, IRB-approved study, prIVCF were placed in consecutive patients who met specific high-risk criteria (history of VTE or hypercoaguable state) prior to total joint arthroplasty. Patients were followed until the IVC filter was removed. Outcomes and complications were recorded per Society of Interventional Radiology guidelines. RESULTS One hundred and nine potentially retrievable IVC filters were placed in 105 patients, who all subsequently underwent joint arthroplasty. One hundred eight IVC filters (98.9%) were retrieved successfully in a mean time of 44.1 days (range 13-183 days). There was 1 failed IVC filter retrieval attempt (0.9%) at 46 days post implantation. Two patients (1.9%) presented with recurrent PE and were successfully treated with anticoagulation prior to IVC filter retrieval. There were no fatalities from perioperative PE. In 1 patient (0.9%), a fractured filter leg had embolized during retrieval. CONCLUSION Potentially retrievable IVC filters are safe and effective for prophylaxis against PE in patients at high-risk for VTE undergoing joint arthroplasty.
Circulation-cardiovascular Interventions | 2017
Kush Desai; James L. Laws; Riad Salem; S. Mouli; M Errea; J. Karp; Yihe Yang; Robert J. Lewandowski; Robert K. Ryu
We appreciate the commentary by Drs Jia and Jiang on our study1 and offer a response. The intent of this study was to identify a retrievable inferior vena cava filter (rIVCF) dwell time when the risk of standard retrieval technique failure increases significantly, thereby requiring advanced techniques to maintain overall technical success. At 7 …
Journal of Vascular and Interventional Radiology | 2010
Jeet Minocha; Ibrahim Idakoji; Ahsun Riaz; J. Karp; Ramona Gupta; Howard B. Chrisman; Riad Salem; Robert K. Ryu; Robert J. Lewandowski
Seminars in Interventional Radiology | 2016
J. Karp; Kush Desai; Riad Salem; Robert K. Ryu; Robert J. Lewandowski