Utility of MRI in detection of PET-CT proven local recurrence of pancreatic adenocarcinoma after surgery.

The aim of this prospective study was to investigate the accuracy and inter-observer reliability of MRI in detection of local recurrence (LR) of pancreatic adenocarcinoma (PAC) after surgery, which was proved by PET-CT and access correlation between functional MRI and PET parameters. Forty-five patients who underwent PET-CT and MRI for follow-up purposes after radical operation of PAC were included. Twenty-three were PET positive (study group) and 22 negative for LR (control group). MR examination was performed within one month after PET-CT and three readers who were blind for PET-CT findings searched LR in T2W, 3D-dynamic post-contrast T1W-FS and DWI sequences, respectively. Sensitivity and specificity were calculated while inter-reader agreement was estimated by Cronbach's Alpha reliability coefficient (CARC). Apparent diffusion coefficient (ADC) of LR was correlated with the size (maximal diameter) and functional PET-CT parameters: mean and maximum standardized uptake values (SUVmean, SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG), using Spearman's correlation coefficient (rS). Sensitivity and specificity among three readers in detecting the LR were 70% and 77-84% in T2W (CARC 0.806), 91-100% and 100% in 3D post-contrast T1W-FS (CARC 0.980), and both 100% in DWI sequences (CARC 1.000). Moderate inverse correlation was found between the ADC and SUVmean (rS = - 0.484), MTV (rS = - 0.494), TLG (rS = - 0.519) and lesion size (rS = - 0.567). MRI with DWI shows high diagnostic accuracy in detecting the LR of PAC in comparison to PET-CT as reference standard. ADC significantly inversely correlates with standard and advanced PET parameters and size of LR.

Prospective study on diagnostic and prognostic significance of postoperative FDG PET/CT in recurrent colorectal carcinoma patients: comparison with MRI and tumor markers.

Current guidelines for follow-up after resection of colorectal cancer (CRC) recommend regular measurements of carcinoembryogenic antigen (CEA) and imaging tests. Multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) are currently primary imaging modalities, while the role of fluorine-18-fluoro-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT), which is recommended in patients with negative MDCT and increased CEA, is still uncertain. Our aim was to compare diagnostic performance and prognostic significance of 18F-FDG PET/CT with MRI and tumor markers CEA and carbohydrate antigen 19-9 (CA 19-9) in detection of recurrent CRC. This prospective study included 35 patients with resected CRC, referred to 18F-FDG PET/CT examination for suspected recurrence. During median follow-up of 24.4±1.5 months 18F-FDG PET/CT and MRI results and tumor marker levels were compared with findings of histopathological examination or with results of clinical and imaging follow-up. Management plan before the 18F-FDG PET/CT scan was considered and compared to the final treatment decision. The sensitivity, specificity, positive and negative predictive value and accuracy of 18F-FDG PET/CT and MRI in detection of recurrent colorectal cancer in patient-based analysis were 92.6%, 75%, 92.6%, 75% and 88.6%, and 65.4%, 66.7%, 85%, 40% and 65.7%, respectively. In lesion-based analysis the sensitivity of 18F-FDG PET/CT and MRI was 83.1% and 68.2%, respectively. The overall accuracy of CEA and CA 19-9 in recurrence detection was 48.6% and 54.3%, respectively. PET/CT induced therapy alterations in 13/35 (37.1%) patients. Progression was observed in 16/35 patients during follow-up, with significantly lower risk of progression in patients with treatment changes based on PET findings (Multivariate Cox regression; p=0.017). In addition, elevated CA 19-9 levels in time of PET scan and male gender carried significantly higher risk of progression (p=0.007 and p=0.016, respectively). Kaplan-Meier Log rank test showed significantly longer progression-free survival time in patients who had treatment plan changed based on PET/CT (p=0.046). We can conclude that 18F-FDG PET/CT showed better sensitivity and accuracy compared to MRI in detection of recurrent colorectal cancer, with much better sensitivity compared to CEA and CA 19-9. Patients with treatment changes based on 18F-FDG PET/CT had significantly better prognosis and longer progression-free survival, while elevated values of CA 19-9 and male gender were associated with worse prognosis.

Metabolic activity of breast cancer metastatic lesions on positron emission tomography/computed tomography: comparison with histological and biological characteristics of primary tumor.

Higher intensity of FDG uptake on PET/CT in primary tumor is seen in patients with IDC compared to ILC, also in high grade tumours, tumours with negative ER and higher Ki67 values, while data are inconsistent in case of relation between primary tumor's PgR and HER2 expression with its metabolic activity levels. On account of the lack of studies that include research of breast cancer metastatic lesion metabolism level and its relation to tumor histology and biology, our goal was to investigate the association of metastatic lesions' glucose metabolism level on PET/CT with different histological and biological characteristics of primary tumor. In a total number of N=100 patients, highest SUVmax values for each patient were used in testing difference between metastatic metabolic activity in patients with different tumor histology, grade, ER, PgR and HER2 status, subtype, as well in testing relation of Ki67 index to metastasis' metabolism level. In testing difference between histological types of breast cancer, SUVmax values were also compared separately for each specific anatomical site (regional and distant lymph nodes, bones and liver). No difference was found regarding metastatic SUVmax values in patients with primary IDC (n=55, median SUVmax 9.70) and ILC (n=34, median SUVmax 7.20) independently of anatomic site, and for each of analysed sites separately. No difference was found as well between SUVmax detected in metastasis in patients with different grade (grade II: n=58, median SUVmax 7.70; grade III: n=12, median SUVmax 10.20), ER (59 positive, median SUVmax 8.50; 22 negative, median SUVmax 8.05), PgR (55 positive, median SUVmax 8.50; 23 negative, median SUVmax 7.80), and HER2 (14 positive, median SUVmax 6.84; 51 negative, median SUVmax 8.63) expression in primary tumor, and between patients with different tumor subtype. Ki67 was also not associated with tumor metastatic SUVmax values (n=11, rs = -0.21, p=0.53). We conclude that there is no association of primary breast cancer histological type, grade, ER, PgR, HER2 and Ki67 expression with metabolic activity in metastasis detected on PET/CT.

Evaluation of the SIOPEN semi-quantitative scoring system in planar simpatico-adrenal MIBG scintigraphy in children with neuroblastoma.

Neuroblastoma is the most common malignancy in children comprising 7.6% of all infantile cancers. MIBG scintigraphy is a mandatory neuroblastoma diagnostic test, which is among others methods, semi-quantified by the SIOPEN method. The aim of this study was to test both the skeletal and the soft tissue segments of the SIOPEN scoring method in the diagnostic milieu and to correlate them with the Curie score. Since there is little knowledge of their diagnostic power, the following variables were tested: VMA, HVA, LDH, and MYCN, ferritin, bone marrow infiltration, the INSS and the INPC classification. The cross-sectional study with repeated measurements of 143 scintigrams was performed on 76 pediatric patients with suspected or proven neuroblastoma, who had been referred to the Center for Nuclear Medicine of the Clinical Center of Serbia in the period 2007-2012. The range of the SIOPEN soft tissue scores was 0-5. The range of the SIOPEN skeletal scores was 0-57. The range of the Curie scores was 0-26. The skeletal SIOPEN scores were significantly higher in bone marrow positive children, in children with pathologically elevated urinary VMA levels and in children having a more advanced clinical stage. There was no difference in the SIOPEN soft tissue score due to higher VMA levels, or depending on the clinical stage and positive bone marrow assessment. There was no difference between the SIOPEN skeletal and soft tissue scores on one hand and the histological grade of the tumor; elevated or normal levels of HVA, LDH, NSE and ferritin, or the presence or absence of MYNC amplification in the neuroblastoma cell line, on the other hand. The results of both SIOPEN scores showed a high linear correlation with the Curie score. The conclusion is that the soft tissue segment of the SIOPEN score needs further elucidation in a more controlled milieu. Excellent correlation between all segments of the two semi-quantitative scoring methods speaks in favor of the application of the complete SIOPEN scoring system in every day mIBG scanning.

Standardized perfusion value of the esophageal carcinoma and its correlation with quantitative CT perfusion parameter values.

PURPOSE: Standardized perfusion value (SPV) is a universal indicator of tissue perfusion, normalized to the whole-body perfusion, which was proposed to simplify, unify and allow the interchangeability among the perfusion measurements and comparison between the tumor perfusion and metabolism. The aims of our study were to assess the standardized perfusion value (SPV) of the esophageal carcinoma, and its correlation with quantitative CT perfusion measurements: blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) of the same tumor volume samples, which were obtained by deconvolution-based CT perfusion analysis. METHODS: Forty CT perfusion studies of the esophageal cancer were analyzed, using the commercial deconvolution-based CT perfusion software (Perfusion 3.0, GE Healthcare). The SPV of the esophageal tumor and neighboring skeletal muscle were correlated with the corresponding mean tumor and muscle quantitative CT perfusion parameter values, using Spearman's rank correlation coefficient (rS). RESULTS: Median SPV of the esophageal carcinoma (7.1; range: 2.8-13.4) significantly differed from the SPV of the skeletal muscle (median: 1.0; range: 0.4-2.4), (Z=-5.511, p<0.001). The cut-off value of the SPV of 2.5 enabled discrimination of esophageal cancer from the skeletal muscle with sensitivity and specificity of 100%. SPV of the esophageal carcinoma significantly correlated with corresponding tumor BF (rS=0.484, p=0.002), BV (rS=0.637, p<0.001) and PS (rS=0.432, p=0.005), and SPV of the skeletal muscle significantly correlated with corresponding muscle BF (rS=0.573, p<0.001), BV (rS=0.849, p<0.001) and PS (rS=0.761, p<0.001). CONCLUSIONS: We presented a database of the SPV for the esophageal cancer and proved that SPV of the esophageal neoplasm significantly differs from the SPV of the skeletal muscle, which represented a sample of healthy tissue. The SPV was validated against quantitative CT perfusion measurements and statistically significant correlation was proved.

Comparison of 18F-FDG PET/CT and MDCT for staging/restaging of non-small cell lung cancer.

UNLABELLED: Multi-detector computed tomography (MDCT) is most commonly used for staging of non-small cell lung cancer (NSCLC). In recent years, 18F- fluorodeoxyglucose positron emission tomography combined with computed tomography (18F-FDG PET/CT) has also been used for the same purpose. Since studies comparing these two methods are scarce, our aim was to determine how the TNM classification and thereby staging of NSCLC compare between 18F-FDG PET/CT and MDCT. 18F-FDG PET/CT and MDCT were collected in 83 patients with NSCLC 3 to 30 days apart (median 17 days). The investigators interpreting 18F-FDG PET/CT were unaware of MDCT results. The Cohen's kappa (κ) was calculated to determine the rate of agreement. The hypothesis was that the strength of agreement between the two methods will be at least moderate (κ>0.40) based on the adopted criteria (κ<0.20 poor; 0.21-0.40 fair; 0.41-0.60 moderate; 0.61-0.80 good; 0.81-1.00 very good agreement). The agreement was moderate for determining the T class (κ=0.45, overall agreement 58%), poor for the N class (κ=0.13, 42%) and fair for the M class (κ=0.22, 58%). The agreement for overall staging of NSCLC was poor (κ=0.20, 45%). The major source of disagreement was that metastases were present more frequently and/or in larger number on 18F-FDG PET/CT than MDCT in the contralateral mediastinal, supraclavicular, and distant lymph nodes, as well as in the bones and suprarenal glands. Since 18F-FDG PET/CT detected more regional and distant metastases than MDCT, we conclude that FDG PET/CT is useful for staging/restaging and planning treatment of patients with NSCLC. KEYWORDS: Non-small cell lung cancer, positron emission tomography, multidetector computed tomography, metastases detection.

The clinical value of scintigraphy of neuroendocrine tumors using (99m)Tc-HYNIC-TOC.

PURPOSE: To assess the value of whole body scintigraphy using (99m)Tc-HYNIC-TOC (Tektrotyd) and with single photon emission computerized tomography (SPECT) in the detection of primary and metastatic neuroendocrine tumors (NETs). METHODS: Thirty patients with different neuroendocrine tumors, mainly gastroenteropancreatic (GEP), were investigated. Whole body scintigraphy was performed 2 h (if necessary 10 min and 24h) after i.v. administration of 740 Mbq (99m)Tc-Tektrotyd, Polatom. In cases of unclear findings obtained by whole body scintigraphy, investigation was followed by SPECT. RESULTS: From 12 patients with NETs of unknown origin, there were 10 true positive (TP), and 2 false negative (FN) findings. Diagnosis was made with SPECT in 6 patients. From 8 patients with gut carcinoids, there were 4 TP, 2 true negative (TN), one FN, and one false positive (FP) finding. Diagnosis was made with SPECT in 2 patients. From 7 patients with neuroendocrine pancreatic carcinomas there were 4 TP and 3 TN findings. Diagnosis was made with SPECT in 2 patients. From 3 patients with gastrinomas there were 2 TP findings and one TN findings. Diagnosis was made with SPECT findings in 2 patients. Sensitivity of (99m)Tc-HYNIC-TOC was 87%, specificity 86%, positive predictive value 95%, negative predictive value 67% and accuracy 87%. CONCLUSION: We concluded that scintigraphy with (99m)Tc-Tektrotyd is an useful method for diagnosis, staging and follow up of the patients with NETs.

CT volumetry of normal pancreas: correlation with the pancreatic diameters measurable by the cross-sectional imaging, and relationship with the gender, age, and body constitution.

PURPOSE: The purpose of this study was to estimate the volume of normal pancreas in adults using the CT volumetry (summation of the areas technique), analyze the correlation between the volume and the diameters of pancreas, which are measurable by the cross-sectional imaging, and assess the relationship with the gender, age, and body constitution. METHODS: 220 CT examinations were analyzed retrospectively (102 females, 118 males; age 16-82, average 56). Following diameters were measured: cranial-caudal-CC(pancreas), CC(body&tail), CC(body), CC(head); anterior-posterior--AP(tail), AP(body), AP(head); lengths--LL(head), L(body&tail); and maximal transversal diameter of the L1 vertebral body (LL(L1)) and thickness of the abdominal subcutaneous fat (AP(ASF)), as markers of body constitution. RESULTS: The average volume of the pancreas was 79.2 ± 24.1 cm3 (ranging from 37.4 to 168.2 cm3). Pancreatic volume strongly correlated with all measured diameters of the pancreas (P < 0.0001). Pancreatic volume significantly correlated with gender (M:F = 86.1:72.8 cm3, P = 0.002) and the LL(L1) (r = 0.185, P = 0.008), and did not correlate with the age (r = -0.110, P = 0.151) and the AP(ASF) (r = -0.115, P = 0.104). Correlation of vertebral body-pancreas volume ratio of each subject and the age was strongly negative (r = -0.202, P = 0.006). CONCLUSIONS: Marked individual variations in normal pancreas volume were observed. Pancreatic volume could be computed using the diameters measurable by the cross-sectional imaging employing the formula: V = (AP(tail) + AP(body))/2 × L(body&tail) × CC(body) + (AP(head)/2)2 × 3.14 × CC(head).

Scintigraphic detection of colon carcinomas with iodinated monoclonal antibodies.

PURPOSE: The aim of this study was to evaluate the clinical reliability of the immunoscintigraphy with iodinated monoclonal antibodies for the detection of metastases and recurrences of colon carcinomas. METHODS: A total of 45 patients with colon carcinoma was investigated with gamma camera, after intravenous application of iodinated monoclonal antibodies. RESULTS: The sensitivity of the method was 90%, specificity 86%, positive predictive value 93%, negative predictive value 80% and accuracy 87%. There was statistically significant relationship between immunoscintigraphic and ultrasonographic (US) findings (p=0.005). Also, there was significant relationship between immunoscintigraphy and Dukes stage (p=0.019). Tumor marker levels were not significantly correlated with immunoscintigraphic findings (p<0.05). Significant difference was noted in patients with positive findings for malignancy on US and immunoscintigraphic findings (p=0.006), i.e. patients with positive findings for malignancy had more frequently immunoscintigraphic findings of malignancy. Correlation with other diagnostic procedures (rectoscopy, colonoscopy, CT) did not show significant correlations. CONCLUSION: We conclude that immunoscintigraphy can be helpful in the detection of metastases and recurrences of colon carcinomas.

The utility of 99mTc-EDDA/HYNIC-TOC scintigraphy for assessment of lung lesions in patients with neuroendocrine tumors.

UNLABELLED: Our aim was to assess clinical utility of 99mTc-EDDA/HYNIC-TOC scintigraphy for evaluation of lung lesions in patients with neuroendocrine tumors (NETs). Single photon emission computed tomography (SPECT) of the thorax and whole body scintigraphy were performed in 34 patients using 99mTc-EDDA/HYNIC-TOC. Visual assessment was complemented by semiquantitative evaluation based on tumor to non-tumor (T/NT) ratio. Clinical, laboratory, and histological findings served as the standard for comparison. Enhanced tracer uptake was observed on both SPECT and whole body scintigraphy in 29 of 34 patients (88% sensitivity). T/NT ratios were significantly higher on SPECT than whole body images (2.96+/-1.07 vs.1.70+/-0.43, p KEYWORDS: 99mTc-EDDA/Hynic-TOC, lung involvement of NETs, T/NT ratio.

Is there a future role for immunoscintigraphy in the diagnosis of colorectal carcinoma?

Immunoscintigraphy combines the advances in immunology and nuclear medicine to target tumor sites. Visualization of colorectal carcinomas is based on different monoclonal antibodies and their fragments against tumor-associated antigens labeled with gamma emitting radionuclides which accumulate in the tumor tissue due to their interaction with corresponding antigens. Available data on the role of immunoscintigraphy in detection of recurrence and metastases of colorectal carcinomas are reviewed. Despite a variety of investigations related to the application of immunoscintigraphy in diagnostics of colorectal cancer, using different radiolabeled immunoreactive agents and imaging methods there has not been a consensus among the investigators regarding the best modality of the method, including the specific radiopharmaceutical for this purpose. Some general conclusions concerning potentials of immunoscintigraphy in such diagnostics, including expectancy of the newly developed SPECT/CT systems, are suggested. The possibilities of PET imaging of colorectal carcinomas using monoclonal antibodies labeled with positron emitting radionuclides, as well as of the radioimmunoguided surgery and radioimmunotherapy are also discussed. Key words: Immunoscintigraphy, colorectal cancer, recurrences, metastases, radioimmunoguided surgery, SPECT/CT.

[Delayed MDCT in preoperative analysis of the hypopharyngeal postcricoid carcinomas].

INTRODUCTION: Determination of borders of the postcricoid tumors is of great significance during preoperative analysis, because it can be of considerable influence on operative treatment and its planning. Therefore, exact demarcation, delineation and opacification of tumor zone on CT analysis is crucial. MATERIAL AND METHOD: Late CT scan delay of 150 sec and slow vein flow of contrast agents of 1 ml/sec is radiological method of choice in preoperative evaluation of carcinoma of the post-cricoid region. For our purposes we used modern MSCT Light Speed GE 64, with slice thick of 2.5 mm (retro recon of 0.625) with software postprocesing. RESULTS AND DISCUSSION: In our study, we have detaily analized 25 patients with clinically proved carcinoma of hypopharynx, of which 8 had the hardest form of tumor. Control group were patients to whom CT scan was done by standard protocol and CT time scan of 50 sec. With all 8 of them, scanned by protocol of delay time of 150 sec, was proved a statistically important validity of interpretation and demarcation of tumors. CONCLUSION: Delay time on CT scanning is proved to be efficient protocol for visualization of neck soft tissues which includes the walls of hypopharynx.

Estimation of the relative liver perfusion using two methods of radionuclide angiography in the patients with hemodynamic disorders in the portal system.

The aim of this study is the assessment of the relative arterial and venous contribution to the total liver blood flow (hepatic perfusion index-HPI), with two methods (S1 and S2), and estimation of their value. With this correction, HPI nonsignificantly increases (p>0.05) in all the groups of patients, with a very high correlation between the HPI (S1) and HPI (S2) values (p<0.01). In comparison to the portal perfusion in controls, values were significantly (p<0.01) lower in chronic active hepatitis and liver cirrhosis and differed between themselves (p<0.01). In the groups of cirrhotic patients with esophageal varices, sclerosated esophageal varices, recanalized umbilical vein, portal thrombosis and cavernous portal vein, portal perfusion was lower (p<0.01) than in controls, chronic active hepatitis and liver cirrhosis without collaterals. Both angioscintigraphic methods are useful for the estimation of the disturbances in the portal system. Because of the more exact estimation of the liver perfusion, S2 is recommended.

The accuracy of ultrasonography in classification of groin hernias according to the criteria of the unified classification system.

BACKGROUND: The modern concept of type-related individualized groin hernia surgery imposes a demand for precise and accurate preoperative determination of the type of groin hernia. The aim of this prospective study was to evaluate the accuracy of ultrasonography in classification of groin hernias, according to the criteria of the unified classification system. Unified classification divides groin hernias into nine types (grades): type I (indirect, small), II (indirect, medium), III (indirect, large), IV (direct, small), V (direct, medium), VI (direct, large), VII (combined-pantaloon), VIII (femoral), and O (other). PATIENTS AND METHODS: One hundred and twenty-five adult patients with clinically diagnosed or suspected groin hernias were examined. Ultrasonography of both groins was performed with a 5 to 10-MHz linear-array transducer. Preoperative ultrasonographic findings of type of groin hernia were compared with the intraoperative findings, which were considered the gold standard. RESULTS: Total accuracy of ultrasonography in determination of type of groin hernia was 96% (119 of 124 correct predictions of type of groin hernia compared with surgical explorations). All hernias of types I, IV, V, VII, and VIII were correctly identified with ultrasonography (sensitivity and specificity 100%). In the remaining five cases of the 124 (4%), hernia was incorrectly classified with ultrasonography: type VI (direct, large) was misdiagnosed as type III (indirect, large) in three cases, type III as type VI in one case, and type III as type II (indirect, medium) in one case. The sensitivity and the specificity of ultrasonography in classifying type II were 100 and 99%, respectively, for type III, 85 and 97%, and for type VI, 90 and 99%. CONCLUSION: Ultrasonography of the groin regions could be used with great accuracy for precise classification of groin hernias in adults. Each type of groin hernia, according to the unified classification system that we used for classification, has a characteristic ultrasonographic presentation, which is demonstrated in this study.

Lipomatosis of the ileocecal valve treated with right hemicolectomy as the consequence of an incomplete diagnostic procedure.

Lipomatosis is an excessive local or general accumulation of fat in the body. It is usually asymptomatic, but depending on localization and size it can cause the patient to experience various difficulties. It can occur within digestive system as a benign mass. We report a case of a 50 year old female presented with mild intestinal symptoms and anemia. She had a lipomatous change of ileocecal valve and due to positive fecal occult blood test, barium enema and incompletely performed colonoscopy was misdiagnosed as a malignant tumor and was treated accordingly.

[The role of wireless capsule endoscopy in the evaluation of patients with suspected small bowel bleeding: a single center experience].

BACKGROUND: Capsule endoscopy (CE) is a new diagnostic tool for the study of patients with suspected small bowel pathology. The aim of the study was to clarify the usefulness of CE in the group of patients with obscure (overt / occult) gastrointestinal (GI) bleeding. PATIENTS AND METHODS: Thirty patients (14 men, 16 women, mean age 50 years, range 9 -79 years) were enrolled in the study. All of them undergone non-diagnostic esophagogastroduodenoscopy, colonoscopy and barium follow-through of the small bowel. All patients underwent capsule endoscopy. Fourteen patients had overt and sixteen occult bleeding. The single senior endoscopist interpreted CE findings in an unblinded manner. RESULTS: CE identified a source of bleeding in 14/30 patients (46.6%). Lesions identified were: tumors in five pts, vascular lesions, Crohnzs disease and Meckelzs diverticulum in two pts and fresh bleeding, segmental celiac disease and colonic diverticulosis in one patient each. CE identified a source of bleeding in 9/14 (64.3%) of patients with ongoing overt bleeding and in only 5/16 (31.3%) of patients with occult bleeding. The positive suspicious findings were seen in 6/30 (20%) of patients (2/14 with overt bleeding and 4/16 with occult bleeding. In 3/14 (21.4%) with overt and 7/16 (43.7%) with occult bleeding findings on CE were negative. All patients with negative findings on follow-up remained asymptomatic for one year. Capsule retention because of unsuspected stenosis occurred in a single patient and required surgery, which resolved the problem. CONCLUSION: CE is an effective diagnostic tool for patients with obscure GI bleeding. It is safe and painless technique which can diagnose the bleeding site beyond the reach of conventional endoscopy. The best candidates for the procedure are those with ongoing and overt bleeding.