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Albert A Nemcek

Publications and source records attributed to Albert A Nemcek.

At least 19 recordsLinked to original sources
PubMed2006

Yttrium-90 microspheres (TheraSphere) treatment of unresectable hepatocellular carcinoma: downstaging to resection, RFA and bridge to transplantation.

PURPOSE: To present the clinical data of 35 patients with T3 unresectable hepatocellular carcinoma (HCC) that were treated with (90)Y with the specific intent of downstaging to resection, radiofrequency ablation (RFA) candidate, United Network for Organ Sharing (UNOS) stage T2 or liver transplantation. MATERIALS AND METHODS: One hundred fifty patients with unresectable HCC were treated with (90)Y microspheres. Of these, 35 patients were UNOS stage T3 at the time of treatment. Patients were followed for clinical toxicities, alterations in model for end-stage-liver disease (MELD) score, tumor response, downstaging to RFA, resection, transplantation, and survival. RESULTS: Nineteen of 34 patients (56%) were successfully downstaged from T3 to T2 following treatment. 11 of 34 (32%) patients treated were downstaged to target lesions measuring 3.0 cm or less. Twenty-three of 35 (66%) were downstaged to either T2 status, lesion < 3.0 cm (RFA candidate), or resection. Seventeen of 34 (50%) had an objective tumor response by WHO criteria. Eight patients (23%) were successfully downstaged and underwent OLT following treatment. 1, 2, and 3-year survival was 84%, 54%, and 27%, respectively. Median survival by Kaplan-Meier analysis for the entire cohort was 800 days. CONCLUSION: These data suggest that intra-arterial (90)Y microspheres can be used as a bridge to transplantation, surgical resection, or RFA.

Aged↗
PubMed2005

Use of yttrium-90 microspheres (TheraSphere) in a patient with unresectable hepatocellular carcinoma leading to liver transplantation: a case report.

Prior to therapy, model for end stage liver disease (MELD) scoring, diagnostic imaging and tumor staging were performed in a patient with T3 HCC. The patient received an orthotopic liver transplant (OLT) 42 days after treatment. The explant specimen showed complete necrosis of the target tumor. Follow-up of this patient has demonstrated no evidence of recurrence. There was no life threatening or fatal adverse experiences related to treatment. This case report documents the natural course, history and outcome of a patient treated with yttrium-90 for unresectable HCC. The patient was downstaged from T3 to T2 and was subsequently transplanted.

Adult↗
PubMed2005

Real-time MRI monitoring of transcatheter hepatic artery contrast agent delivery in rabbits.

RATIONALE AND OBJECTIVES: We sought to test the hypothesis that transcatheter hepatic artery delivery of dilute gadolinium (Gd) in rabbits can be monitored in real-time using magnetic resonance imaging (MRI). MATERIALS AND METHODS: Catheters (2F) were inserted via a femoral access into the hepatic arteries of six New Zealand White rabbits under radiographic guidance. After transfer to a 1.5-T MRI scanner, 26 separate hepatic artery injections of 2 mL of 4% Gd and 14 sham injections were performed. Real-time imaging of all injections was acquired using two-dimensional projection inversion recovery-gradient echo. Films of these 40 injections, as well as 10 random repeats, were independently reviewed in a randomized, blinded fashion by two Certificate of Added Qualification-certified interventional radiologists. Observers reported (i) if Gd injection occurred and (ii) if so, the location of delivery. For each observer, we compared sensitivity/specificity for real-time visualization of contrast injection and accuracy of injection localization. Interobserver and intraobserver variability was assessed using the kappa statistic. X-ray digital subtraction angiography was the gold standard for all MRI studies. RESULTS: Both observers had a sensitivity of 100% and a specificity of 93%. Accuracy for intrahepatic contrast delivery was 77% for both observers. Accuracy for extrahepatic delivery was 92% and 96%, respectively. Both interobserver and intraobserver agreement was outstanding. CONCLUSIONS: In rabbits, MRI allows for accurate real-time monitoring of transcatheter hepatic artery delivery of contrast agent. Localization accuracy is higher outside the liver than within the liver. These results can be used as a baseline reference for comparing the accuracy of delivery of Gd-tagged therapies in the future.

Animals↗
PubMed2005

Incidence of nonviable leiomyomas on contrast material-enhanced pelvic MR imaging in patients referred for uterine artery embolization.

PURPOSE: To assess the incidence of nonviable leiomyomas in patients referred for uterine artery embolization (UAE) with use of contrast material-enhanced pelvic magnetic resonance (MR) imaging and to determine the effect of this information on interventional radiologists' decision to perform UAE or consider other treatment options. MATERIALS AND METHODS: One hundred consecutive women referred for UAE for treatment of symptomatic leiomyomas were studied. Of these, 94 patients underwent MR imaging examinations, which were retrospectively reviewed. Leiomyoma locations (ie, submucosal, intramural, subserosal), volume (length, width, height), and percent nonenhancement were recorded and the measurements were divided into four categories (0-25%, 25%-50%, 50%-75%, 75%-100%). RESULTS: In 94 patients, 381 leiomyomas exceeding 3 cm in each dimension were recorded. Twenty-one patients (22%) did not receive embolization based on the findings of preprocedural MR imaging. In six patients (6%), there were nine nonviable dominant tumors with an average size of 7.8 cm3. These cases were not treated with UAE. Another 15 patients (16%) did not undergo UAE based on other MR imaging findings (including uterine size, presence of isolated adenomyosis, and endometrial lesions). CONCLUSIONS: Contrast material-enhanced MR imaging before UAE is highly useful in the evaluation of patients referred for UAE. MR imaging can be used to determine the viability of tumors and detect other findings that preclude UAE.

Adult↗
PubMed2004

Microcystic adenoma of the pancreas: clinical, radiologic, and cytologic features.

BACKGROUND: Cytology literature on pancreatic microcystic adenoma is sparse. It is important to separate microcystic adenoma from adenocarcinoma and mucinous cystic neoplasms on aspiration cytology, because patients with microcystic adenoma can be treated conservatively unless they are symptomatic. Potential pitfalls with endoscopic ultrasound (EUS) sampling of these lesions is discussed. METHODS: From January 1991 through June 2003, 10 patients with microcystic adenoma of the pancreas were diagnosed on fine-needle aspiration cytology. An additional patient, who was diagnosed with a mucinous cystic neoplasm by EUS sampling, was rediagnosed with microcystic adenoma on the excised specimen. Aspirate smears, cell blocks, core biopsies, subsequent excision (if any), and special stains were reviewed. Imaging studies and clinical data were available from the majority of patients. RESULTS CLINICAL RESULTS: The patients included 5 females and 6 males who ranged in age from 45 years to 84 years. Radiology studies showed tumors, which were heterogeneous with areas of fluid density and septations, located in the head, body, or tail of the pancreas. The masses ranged in size from 1 cm to 17 cm. The radiographic impression was highly suggestive of microcystic adenoma in six patients; detailed radiologic information was not available from three patients. On follow-up, six patients were alive and well at the last follow-up available, two patients died of unrelated sepsis, and three patients were lost to follow-up. Three of 11 patients underwent a Whipple resection. Cytology results: The cytologic features identified included the following: 1) Bland tumor cells were seen in sheets or small groups with a lack of nuclear abnormalities and moderate-to-scant cytoplasm with occasional clearing or vacuolation. Naked nuclei were present occasionally. Tumor cells were distinguishable from acinar cells based on larger cell size and granular cytoplasm in which prominent nucleoli were seen. 2) Relatively acellular, fibrovascular stroma was seen, usually located between tumor cells. 3) Calcifications were seen in four of eleven tumors. One tumor sampled by EUS revealed fragments of glandular-type epithelium with minimal atypia and was diagnosed erroneously as a mucinous cystic neoplasm. Cell blocks or core biopsies from most tumors showed fragments of dense stroma and cystic spaces lined by flattened epithelial cells. Subsequent Whipple resection in three patients showed histologic features of microcystic adenoma. Special stains performed in select tumors were positive for cytokeratin, carbohydrate antigen 19.9, and periodic acid-Schiff stain. Calretinin staining was negative in the tumor cells. CONCLUSIONS: A cytologic diagnosis of microcystic adenoma is possible based on the criteria described above. Cell block and/or core biopsy, special stains, and radiologic information are key in making a definitive diagnosis. Patients with microcystic adenoma are spared a major surgical procedure unless they are symptomatic. With the EUS-guided modality of pancreatic sampling, caution should be exercised in misinterpreting benign glandular epithelium derived from the stomach or small bowel as a mucinous cystic neoplasm.

Adenoma↗
PubMed2004

Upper extremity deep venous thrombosis: interventional management.

Upper extremity deep venous thrombosis, previously thought to be a relatively innocuous disorder in comparison to lower extremity deep venous thrombosis, has recently begun to receive the attention it merits. Its optimal management remains controversial despite the development of several new techniques and devices which allow more rapid removal of thrombus and treatment of underlying venous stenotic disease. The following article provides a framework to discuss its treatment, with the emphasis on endovascular management.

Disease Management↗
PubMed2004

Comparison of percutaneous management techniques for recurrent malignant ascites.

The Pleurx subcutaneous tunneled catheter is approved for repeated, long-term drainage of malignant pleural effusions; however, there is limited literature describing its use in malignant ascites. The authors compared the safety and efficacy of two percutaneous drainage methods: large volume paracentesis and Pleurx catheter placement over a 41-month period. The Pleurx catheter provided effective palliation with a complication rate similar to that for large volume paracentesis, while preventing the need for frequent trips to the hospital for repeated percutaneous drainage.

Adult↗
PubMed2003

Preoperative evaluation of the entire hepatic vasculature in living liver donors with use of contrast-enhanced MR angiography and true fast imaging with steady-state precession.

PURPOSE: To preoperatively assess the entire hepatic vasculature in living related liver donors with use of a combination of contrast material-enhanced magnetic resonance (MR) angiography and true fast imaging with steady-state precession (FISP). MATERIALS AND METHODS: Twenty-five living potential liver donors were examined preoperatively on a 1.5T Siemens Sonata system. Twenty-four underwent surgery and two had catheter angiography performed to delineate complex anatomy. Contiguous 5-mm-thick, sub-second true FISP images of the liver were initially obtained during breath-holding in axial and coronal planes (repetition time [TR]/echo time [TE], 3.2/1.6; flip angle, 70 degrees ). MR angiography was performed with use of a three-dimensional (3D) gradient-echo fast low-angle shot (FLASH) pulse sequence (TR/TE, 3.0/1.2; flip angle, 25 degrees ), with 40 mL of Gadolinium DTPA injected at a rate of 2 mL/sec. One precontrast and two postcontrast coronal 3D volumes were acquired, each in a 20-second breath-hold, and two subtracted 3D sets were calculated. Arterial anatomy was assessed with use of maximum-intensity projection, volume rendering, and multiplanar reformatting algorithms. Hepatic and portal venous anatomy was evaluated with use of the true FISP images and the venous phase of the MR angiogram. Visualization of hepatic arterial branches was noted. Visualization of portal vein branches was scored on a scale of 0-5. The presence of anatomic variants was noted. Vascular anatomy was confirmed at the time of surgery and at catheter angiography. RESULTS: Segmental branch vessels were visualized on MR angiography in the majority of cases. The segment four branch was identified in 96% patients. Variant arterial anatomy was seen in 50% of patients. MR angiography detected 10 of 11 arterial variants found at surgery and angiography. Visualization of portal vein branches was generally higher with true FISP compared to MR angiography. Twenty-four percent of patients had variant portal venous anatomy. Caudal hepatic veins were identified in 60% of patients, of which eight were significant (>5 mm). Hepatic and portal venous anatomy was accurately predicted by true FISP and MR angiography in all patients who went on to undergo surgery. CONCLUSION: Preoperative imaging with use of a combination of contrast-enhanced MR angiography and true FISP provides a comprehensive assessment of the entire hepatic vasculature in living liver donors.

Adult↗
PubMed2003

Sonography of delayed effects of uterine artery embolization on ovarian arterial perfusion and function.

OBJECTIVE: We aimed to assess the delayed effects of uterine artery embolization on ovarian arterial perfusion and function by performing ovarian sonography immediately before and after uterine artery embolization, as well as several months later. CONCLUSION: Although persistent loss of detectable arterial perfusion after uterine artery embolization occurs in some women, most patients reestablish arterial perfusion and do not develop symptoms of ovarian failure.

Adult↗
PubMed2002

The effect of pelvic MR imaging on the diagnosis and treatment of women with presumed symptomatic uterine fibroids.

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.

Adult↗
PubMed2002

Gadolinium-enhanced 3D MR angiography of renal artery stenosis: a pilot comparison of maximum intensity projection, multiplanar reformatting, and 3D volume-rendering postprocessing algorithms.

RATIONALE AND OBJECTIVES: The authors compared diagnostic accuracy of maximum intensity projection (MIP), multiplanar reformatting (MPR), and three-dimensional (3D) volume rendering (VR) in the evaluation of gadolinium-enhanced 3D magnetic resonance (MR) angiography of the renal arteries. They hypothesized that VR is as accurate as or more accurate than MIP and MPR at depicting renal artery stenosis. MATERIALS AND METHODS: The study group comprised 28 consecutive patients who underwent gadolinium-enhanced 3D MR angiography of the renal arteries. Studies were postprocessed to display images in MIP, MPR, and VR formats. Digital subtraction angiography (DSA), when performed (nine of 28 patients), was the standard for comparison. For each main renal artery, an estimate of percentage stenosis was made for any stenoses detected by three independent radiologists. For calculation of sensitivity, specificity, and accuracy, MR angiographic stenosis estimates were categorized as mild (0%-39%), moderate (40%-69%), or severe (> or = 70%). DSA stenosis estimates of 70% or greater were considered hemodynamically significant. RESULTS: Analysis of variance demonstrated MIP estimates of stenosis were statistically greater than VR estimates in two readers and greater than MPR estimates in all readers for all patients. MIP images also showed the largest mean difference from DSA stenosis estimates for all three readers. For both VR and MPR, mean differences between MR angiographic stenoses estimates and DSA estimates reached significance for only one reader, whereas, for MIP versus DSA, mean differences reached significance for all three readers. Although not statistically significant compared with DSA, accuracies of VR (87%) and MPR (89%) were greater than that of MIP (81%). CONCLUSION: In this pilot study, MIP was the least accurate of the three image display algorithms tested. VR and MPR yielded similar values for each method of comparison.

Adult↗
PubMed2002

Comparison of intraarterial and IV gadolinium-enhanced MR angiography with digital subtraction angiography for the detection of renal artery stenosis in pigs.

OBJECTIVE: Catheter-based intraarterial injections of gadolinium are useful during MR imaging-guided endovascular procedures to generate rapid vascular road maps. Using an animal model of renal artery stenosis, we tested the hypothesis that intraarterial gadolinium-enhanced MR angiography is as accurate as IV gadolinium-enhanced MR angiography and digital subtraction angiography (DSA). We also tested the hypothesis that intraarterial MR angiography uses less gadolinium than IV MR angiography. MATERIALS AND METHODS: We induced bilateral renal artery stenosis in five pigs. All pigs underwent comparative imaging with DSA, IV MR angiography, and aortic catheter-directed intraarterial MR angiography. For IV and intraarterial MR angiography, we used the same three-dimensional acquisition. We assessed differences in quantitative stenosis measurements among DSA, IV MR angiography, and intraarterial MR angiography using the Wilcoxon's signed rank test. RESULTS: Mean stenosis measurements (+/-SD) were as follows: DSA, 58% +/- 12%; IV MR angiography, 63% +/- 9.3%; and intraarterial MR angiography, 64% +/- 11%. There were no statistically significant differences in accuracy between DSA and IV MR angiography (p = 0.06), DSA and intraarterial MR angiography (p = 0.16), or IV and intraarterial MR angiography (p = 0.70). Intraarterial MR angiography used a mean gadolinium dose of 5.6 mL, compared with 9 mL for IV MR angiography. CONCLUSION: In swine, IV and intraarterial MR angiography have a similar accuracy for detecting renal artery stenosis. Intraarterial MR angiography uses smaller doses of injected gadolinium.

Angiography, Digital Subtraction↗
PubMedDate not supplied

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

When 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.

Adult↗
PubMedDate not supplied

Treatment of unresectable primary and metastatic liver cancer with yttrium-90 microspheres (TheraSphere): assessment of hepatic arterial embolization.

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.

Aged↗