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Featured researches published by Howard B. Chrisman.


Gastroenterology | 2011

Radioembolization results in longer time-to-progression and reduced toxicity compared with chemoembolization in patients with hepatocellular carcinoma

Riad Salem; Robert J. Lewandowski; Laura Kulik; Ahsun Riaz; Robert K. Ryu; Kent T. Sato; Ramona Gupta; Paul Nikolaidis; Frank H. Miller; Vahid Yaghmai; S.M. Ibrahim; Seanthan Senthilnathan; Talia Baker; Vanessa L. Gates; Bassel Atassi; Steven Newman; Khairuddin Memon; Richard Chen; Robert L. Vogelzang; Albert A. Nemcek; Scott A. Resnick; Howard B. Chrisman; James Carr; Reed A. Omary; Michael Abecassis; Al B. Benson; Mary F. Mulcahy

BACKGROUND & AIMS Chemoembolization is one of several standards of care treatment for hepatocellular carcinoma (HCC). Radioembolization with Yttrium-90 microspheres is a novel, transarterial approach to radiation therapy. We performed a comparative effectiveness analysis of these therapies in patients with HCC. METHODS We collected data from 463 patients who were treated with transarterial locoregional therapies (chemoembolization or radioembolization) over a 9-year period. We excluded patients who were not appropriate for comparison and analyzed data from 245 (122 who received chemoembolization and 123 who received radioembolization). Patients were followed for signs of toxicity; all underwent imaging analysis at baseline and follow-up time points. Overall survival was the primary outcome measure. Secondary outcomes included safety, response rate, and time-to-progression. Uni- and multivariate analyses were performed. RESULTS Abdominal pain and increased transaminase activity were more frequent following chemoembolization (P < .05). There was a trend that patients treated with radioembolization had a higher response rate than with chemoembolization (49% vs 36%, respectively, P = .104). Although time-to-progression was longer following radioembolization than chemoembolization (13.3 months vs 8.4 months, respectively, P = .046), median survival times were not statistically different (20.5 months vs 17.4 months, respectively, P = .232). Among patients with intermediate-stage disease, survival was similar between groups that received chemoembolization (17.5 months) and radioembolization (17.2 months, P = .42). CONCLUSIONS Patients with HCC treated by chemoembolization or radioembolization with Yttrium-90 microspheres had similar survival times. Radioembolization resulted in longer time-to-progression and less toxicity than chemoembolization. Post hoc analyses of sample size indicated that a randomized study with > 1000 patients would be required to establish equivalence of survival times between patients treated with these two therapies.


Journal of Vascular and Interventional Radiology | 2000

The Impact of Uterine Fibroid Embolization on Resumption of Menses and Ovarian Function

Howard B. Chrisman; Mark B. Saker; Robert K. Ryu; Albert A. Nemcek; Melvin V. Gerbie; Magdy P. Milad; Steven J. Smith; Luke E. Sewall; Reed A. Omary; Robert L. Vogelzang

PURPOSE To evaluate the effect of uterine fibroid embolization (UFE) on menstruation and ovarian function. METHODS The authors performed an observational study of UFE for the treatment of symptomatic fibroids. All patients had regular predictable menses before intervention and none had clinical or laboratory findings of menopause. UFE was performed with use of standard methods with 355-700-microm-diameter polyvinyl alcohol (PVA) foam particles. The incidence of ovarian failure was calculated for women younger than 45 years and for those 45 years or older, based on retrospective stratification by age. The authors assessed statistical differences in ovarian failure between the two age groups with use of the X2 test. RESULTS Sixty-six premenopausal women (age range, 30-55 years) underwent bilateral UFE and were followed for an average of 21 weeks (range, 12-77 weeks). In 56 of 66 (85%) patients, regular menses resumed after an average of 3.5 (range, 1-8) weeks. In 10 of 66 (15%) patients, regular menses did not resume. Clinical and biochemical findings consistent with ovarian failure and presumed menopause were seen in nine of 10 patients without resumption of menses (14% of total patients). Ovarian failure occurred in nine of 21 (43%) women older than 45 years and in none of the 45 women younger than 45 years (P < .05). There were no differences in presenting symptoms, amount of PVA used, or fibroid size between patients who did and did not resume menses. CONCLUSION The majority of patients undergoing UFE will have resumption of menses, but the incidence of postprocedure ovarian failure is considerably higher than reported to date. Loss of menses induced by UFE is significantly more likely to occur in women older than 45 years.


CardioVascular and Interventional Radiology | 2006

Treatment of Unresectable Primary and Metastatic Liver Cancer with Yttrium-90 Microspheres (TheraSphere®): Assessment of Hepatic Arterial Embolization

Kent T. Sato; Robert J. Lewandowski; James T. Bui; Reed A. Omary; Russell D. Hunter; Laura Kulik; Mary F. Mulcahy; David M. Liu; Howard B. Chrisman; Scott A. Resnick; Albert A. Nemcek; Robert L. Vogelzang; Riad Salem

In Canada and Europe, yttrium-90 microspheres (TheraSphere®; MDS Nordion, Ottawa, Canada) are a primary treatment option for primary and secondary hepatic malignancies. We present data from 30 patients with hepatocellular carcinoma (HCC) and metastatic liver disease treated with TheraSphere from a single academic institution to evaluate the angiographically evident embolization that follows treatment. Seven interventional radiologists from one treatment center compared pretreatment and posttreatment angiograms. The reviewers were blinded to the timing of the studies. The incidence of postembolization syndrome (PES) was determined as well as objective tumor response rates by the World Health Organization (WHO), Response Evaluation Criteria in Solid Tumors (RECIST), and European Association for the Study of the Liver (EASL) criteria. There were 420 independent angiographic observations that were assessed using the chi-squared statistic. The pretreatment and posttreatment angiograms could not be correctly identified on average more than 43% of the time (p = 0.0004). The postprocedure arterial patency rate was 100%. The objective tumor response rates for all patients were 24%, 31%, and 72% for WHO, RECIST, and EASL criteria, respectively. All of the patients tolerated the procedure without complications and were treated on an outpatient basis, and four patients had evidence of PES. This treatment method does not result in macroscopic embolization of the hepatic arteries, thereby maintaining hepatic tissue perfusion. These data support the principle that the favorable response rates reported with TheraSphere are likely due to radiation and microscopic embolization rather than flow-related macroscopic embolization and ischemia.


Radiology | 2010

Chemoembolization for Hepatocellular Carcinoma: Comprehensive Imaging and Survival Analysis in a 172-Patient Cohort

Robert J. Lewandowski; Mary F. Mulcahy; Laura Kulik; Ahsun Riaz; Robert K. Ryu; Talia Baker; S.M. Ibrahim; Michael I. Abecassis; Frank H. Miller; Kent T. Sato; Seanthan Senthilnathan; Scott A. Resnick; Ramona Gupta; Richard Chen; Steven Newman; Howard B. Chrisman; Albert A. Nemcek; Robert L. Vogelzang; Reed A. Omary; Al B. Benson; Riad Salem

PURPOSE To determine comprehensive imaging and long-term survival outcome following chemoembolization for hepatocellular carcinoma (HCC). MATERIALS AND METHODS One hundred seventy-two patients with HCC treated with chemoembolization were studied retrospectively in an institutional review board approved protocol; this study was HIPAA compliant. Baseline laboratory and imaging characteristics were obtained. Clinical and laboratory toxicities following treatment were assessed. Imaging characteristics following chemoembolization were evaluated to determine response rates (size and necrosis) and time to progression (TTP). Survival from the time of first chemoembolization treatment was calculated. Subanalyses were performed by stratifying the population according to Child-Pugh, United Network for Organ Sharing, and Barcelona Clinic for Liver Cancer (BCLC) staging systems. RESULTS Cirrhosis was present in 157 patients (91%); portal hypertension was present in 139 patients (81%). Eleven patients (6%) had metastases at baseline. Portal vein thrombosis was present in 11 patients (6%). Fifty-five percent of patients experienced some form of toxicity following treatment; 21% developed grade 3 or 4 bilirubin toxicity. Post-chemoembolization response was seen in 31% and 64% of patients according to size and necrosis criteria, respectively. Median TTP was 7.9 months (95% confidence interval: 7.1, 9.4) but varied widely by stage. Median survival was significantly different between patients with BCLC stages A, B, and C disease (stage A, 40.0 months; B, 17.4 months; C, 6.3 months; P < .0001). CONCLUSION The determination of TTP and survival in patients with HCC is confounded by tumor biology and background cirrhosis; chemoembolization was shown to be a safe and effective therapy in patients with HCC.


Journal of Vascular and Interventional Radiology | 2002

The Effect of Pelvic MR Imaging on the Diagnosis and Treatment of Women with Presumed Symptomatic Uterine Fibroids

Reed A. Omary; Syam Vasireddy; Howard B. Chrisman; Robert K. Ryu; F. Scott Pereles; James Carr; Scott A. Resnick; Albert A. Nemcek; Robert L. Vogelzang

PURPOSE To determine if magnetic resonance (MR) imaging significantly alters the diagnostic thinking and treatment plans of interventional radiologists during the evaluation of women for uterine fibroid embolization (UFE) for presumed uterine fibroids. MATERIALS AND METHODS At a single institution, interventional radiologists prospectively completed questionnaires (n = 60) before and after MR imaging was performed in their evaluation of women presenting for potential UFE. The questionnaires asked these physicians the probability (0%-100%) of their most likely diagnosis before MR imaging and after receiving the MR imaging information. They were also asked their anticipated and final treatment plans. Diagnostic confidence gains and the proportion of patients with changed initial diagnoses or anticipated management were calculated. The Wilcoxon signed-rank test was used to assess gains in diagnostic confidence. RESULTS MR imaging caused a mean gain in diagnostic confidence of 22% (P <.0001). MR imaging changed initial diagnoses in 11 patients (18%). Immediate clinical management changed in 13 patients (22%). UFE was not performed in 11 of 57 women (19%) who were anticipated before MR imaging to receive UFE. CONCLUSIONS MR imaging significantly alters the diagnoses and treatment plans of interventional radiologists evaluating women with presumed symptomatic fibroids. MR imaging should be considered in all patients before UFE.


Journal of Vascular and Interventional Radiology | 2001

The Vascular Impact of Uterine Artery Embolization: Prospective Sonographic Assessment of Ovarian Arterial Circulation

Robert K. Ryu; Howard B. Chrisman; Reed A. Omary; Simka Miljkovic; Albert A. Nemcek; Mark B. Saker; Scott A. Resnick; James Carr; Robert L. Vogelzang

PURPOSE The etiology of premature ovarian failure after uterine artery embolization (UAE) is unknown. The authors prospectively assessed ovarian arterial circulation before and after UAE with use of ultrasonography (US). The authors hypothesize that nontarget embolization of the ovary occurs during routine UAE. MATERIALS AND METHODS Twenty-three women (mean age of 42.6 years; range, 35-51 y) participated in the study. Grayscale, color, and pulsed-wave Doppler US studies were performed immediately before and after UAE. Resistive index (RI) and pulsatility index (PI) were calculated. The proportion of women who developed increased vascular impedance after UAE was statistically assessed with use of the Yates-corrected chi(2) test. RESULTS Seventeen of 23 patients (74%) completed the study. Nine of 17 (54%) showed complete loss of ovarian arterial perfusion after UAE. Six of 17 (35%) had increases in RI and PI, whereas two of 17 (11%) had decreases in RI and PI. The increase in vascular impedance after UAE in 15 of 17 patients was significant (P <.0001). CONCLUSION Loss of detectable ovarian arterial perfusion occurs in the majority of patients undergoing UAE. Ovarian vascular impedance increases in nearly all patients as a result of UAE. The authors conclude that inadvertent nontarget embolization of the ovarian arterial bed occurs during routine UAE.


Journal of Vascular and Interventional Radiology | 1999

Peripherally Inserted Central Catheters: Guidance with Use of US versus Venography in 2,650 Patients

Howard B. Chrisman; Reed A. Omary; Albert A. Nemcek; Robert K. Ryu; Mark B. Saker; Robert L. Vogelzang

PURPOSE To compare technical success and initial complication rates of peripherally inserted central catheters (PICCs) by interventional radiologists using ultrasound (US) or venographic guidance. MATERIALS AND METHODS With use of a computer database, the authors retrospectively reviewed 2,650 procedures, 2,126 of which were performed with US and 524 with venography. Technical success was defined as placement of a PICC. Initial complications were defined as development of a hematoma, inadvertent arterial puncture, or neuropathy. Statistical significance was assessed using the chi2 test. RESULTS During 33 consecutive months, 2,650 procedures were performed with a complication rate of 1.0%. The technical success rate was 95.8% for venography and 99.6% for US. The initial complication rate was 0.75% for venography and 1.08% for US. There was no statistically significant difference in immediate complication rates (P = .50); however, there is statistical significance in regard to technical success (P < .001). CONCLUSION There is no difference in initial complication rates when comparing US and venographic guidance for PICC insertion. The decision to use either method can be based on clinical grounds and/or physician preference, although US has a higher initial success rate.


CardioVascular and Interventional Radiology | 2000

Treatment of Stomal Variceal Hemorrhage with TIPS: Case Report and Review of the Literature

Robert K. Ryu; Albert A. Nemcek; Howard B. Chrisman; Mark B. Saker; Andres T. Blei; Reed A. Omary; Robert L. Vogelzang

We report a case in which recurrent hemorrhage from stomal varices was successfully treated by placement of a TIPS in a patient with prior colectomy for inflammatory bowel disease. Although several treatment options have been reported for this entity we believe that TIPS offers minimally invasive and definitive treatment.


CardioVascular and Interventional Radiology | 2003

Comparison of pain after uterine artery embolization using tris-acryl gelatin microspheres versus polyvinyl alcohol particles

Robert K. Ryu; Reed A. Omary; Michael J. Sichlau; Aheed J. Siddiqi; Howard B. Chrisman; Albert A. Nemcek; Robert L. Vogelzang

AbstractWhen compared in a uterine artery embolization (UAE) animal model, Embospheres (ES) (Biosphere Medical, Rockland, MA) were found to induce less uterine ischemia than polyvinyl alcohol (PVA) particles. Given this finding, we aimed to test the hypothesis that ES is associated with less pain after UAE than PVA in human patients. We performed retrospective analysis on data from 72 consecutive UAE patients, collected from a prospectively acquired database. Patient-controlled analgesia (PCA) pump-delivered morphine sulfate (MS) dosages were compared between patients who received ES versus PVA. Subjective pain scores (SPS) were also compared between the two groups. Secondary outcome measures, including embolic volume and clinical outcome data, were also collected. Linear regression and t-test statistical analyses were performed. Null hypotheses were rejected at the p < 0.05 level. Mean follow-up period in the PVA population was 178 days (range 28–426), versus 96 days (range 24–197) in the ES population. The mean MS doses used by ES and PVA patients were 37.2 (s.d. 23.5) versus 47.1 (s.d. 26.8), respectively. This difference was not significant (p > 0.15). Utilizing a standard 0–10 pain scale, the mean peak SPS for the ES and PVA groups were 5.58 (s.d. 2.77) and 5.07 (s.d. 2.99), respectively. The difference was not significant. The mean amount of embolic material used in each ES and PVA patient was 4.86 cc (s.d. 3.01) and 3.52 cc (s.d. 1.63), respectively. The difference revealed a strong trend toward statistical significance (p = 0.05). There was one treatment failure in each group of patients. Within both patient samples, no significant correlation was found when comparing the volume of embolic used and subsequent MS dose. Despite a strong trend toward a significantly higher volume of ES used per patient, there is no subjective or objective difference in pain after UAE with ES when compared to PVA.


Journal of Vascular and Interventional Radiology | 2000

Early failure of aortoiliac kissing stents: histopathologic correlation.

Mark B. Saker; William Frank Oppat; Sara A. Kent; Robert K. Ryu; Howard B. Chrisman; Albert A. Nemcek; William H. Pearce; Robert L. Vogelzang

JVIR 2000; 11:333–336 THE application of bilateral iliac stents, or kissing stents, for atherosclerotic disease of the aortic bifurcation has been described in the literature (1–4). They have been described in cases of failed or suboptimal percutaneous transluminal angioplasty, or as primary therapy. Some practitioners favor the use of stents as a primary form of treatment, due to optimal immediate angiographic and hemodynamic results when compared to percutaneous transluminal angioplasty alone. A small series of cases of kissing stents at the aortic bifurcation has been reported (4). Long-term patency rates are unknown. There is very little known about the natural history of protruding metallic stents from the iliac arteries into the abdominal aorta. We report a case of early failure of aortoiliac kissing stents, in which a surgical specimen was obtained for cytopathology analysis.

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Robert L. Vogelzang

University of Wisconsin-Madison

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Reed A. Omary

Vanderbilt University Medical Center

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Robert K. Ryu

University of Wisconsin-Madison

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Albert A. Nemcek

University of Wisconsin-Madison

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Riad Salem

Northwestern University

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James Carr

Northwestern University

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