The diagnostic performance and added value of (18)F-FDG PET/CT in the detection of liver metastases in recurrent colorectal carcinoma patients.

OBJECTIVE: The aim of this study was to assess the value of (18)F-fluorodeoxyglucose ((18)F-FDG) PET/CT in detection of liver metastases in patients with suspected recurrent colorectal carcinoma, as well as to compare diagnostic performance of (18)F-FDG PET/CT with conventional imaging methods (MDCT). SUBJECTS AND METHODS: This study included 73 patients with resected primary colorectal adenocarcinoma referred for (18)F-FDG PET/CT to the National PET Center, at the Clinical Center of Serbia, Belgrade, from January 2010 to May 2013, with suspicion of recurrence. The patients underwent (18)F-FDG PET/CT examination on a 64-slice hybrid PET/CT scanner (Biograph, TruePoint64, Siemens Medical Solutions, Inc. USA). Prior to (18)F-FDG PET/CT all patients underwent contrast-enhanced MDCT. Findings of (18)F-FDG PET/CT and MDCT were compared to findings of subsequent histopathological examinations or with results of clinical and imaging follow-up over at least six months. Final diagnosis of liver metastases of colorectal cancer was made either by histopathological examination of specimen after biopsy or surgery, or based on clinical, laboratory and imaging evaluation during first six months after PET/CT scan. RESULTS: In detection of liver metastases (18)F-FDG PET/CT showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 83.3%, 95.3%, 92.6%, 89.1% and 90.4%, respectively. In addition, MDCT showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy in detection of liver metastases of 60%, 88.4%, 78.3%, 76% and 76.7%, respectively. There was significant difference in sensitivity (83.3% vs 60%; P=0.045) between these two methods. In addition, significant difference was observed in accuracy between PET/CT and MDCT (90.4% vs 76.7%; P=0.016). The higher specificity in visualization of liver metastases was also achieved by (18)F-FDG PET/CT compared to MDCT (95.3% vs 88.4%), but this difference was not significant (P=0.37). CONCLUSION: (18)F-FDG PET/CT was highly sensitive, specific and accurate method in detection of liver metastases in patients with suspected recurrent colorectal carcinoma in our study. This hybrid imaging showed superior diagnostic performance in evaluation of suspected colorectal cancer liver metastases compared to conventional imaging.

Can (18)F-FDG PET/CT scan change treatment planning and be prognostic in recurrent colorectal carcinoma? A prospective and follow-up study.

OBJECTIVE: To prospectively study whether in patients with resected primary colorectal cancer fluorine- 18-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) examination could diagnose the stage, specify treatment procedure and be prognostic. SUBJECTS AND METHODS: This prospective study included 75 patients with resected primary colorectal adenocarcinoma referred for (18)F-FDG PET/CT to the National PET Center, at the Clinical Center of Serbia, Belgrade, from January 2010 to May 2013. Findings of (18)F-FDG PET/CT were compared to findings of subsequent histopathological examinations or with results of clinical and imaging follow-up. Patients were followed after PET/CT examination for a mean follow-up time of 16.7±5.9 months. RESULTS: In the detection of recurrent disease (18)F-FDG PET/CT showed overall sensitivity, specificity, PPV, NPV and accuracy of 96.6%, 82.4%, 94.9%, 87.5% and 93.3%, respectively. In the detection of stages I and II sensitivity, specificity and accuracy of (18)F-FDG PET/CT were: 88%, 96.6% and 94.7%, respectively, and in the detection of stages III and IV sensitivity, specificity and accuracy were 94.9%, 87.5% and 93.3%, respectively. These findings prevented or changed intended surgical treatment in 12/32 cases. Univariate and multivariate Cox proportional regression analyses revealed that metastatic recurrence (stages III and IV) was the only and independent prognostic factor of disease progression during follow-up (P=0.012 and P=0.023, respectively). Although, survival seemed better in patients with local recurrence compared to metastatic recurrent disease, this difference did not reach significance (Log-rank test; P=0.324). In addition, progression-free survival time was significantly longer in patients in whom (18)F-FDG PET/CT scan led to treatment changes (Log-rank test; P=0.037). CONCLUSION: (18)F-FDG PET/CT was sensitive and accurate for the detection and staging of local and metastatic recurrent colorectal carcinoma, with higher specificity in the detection of local recurrences. The (18)F-FDG PET/CT scan induced treatment changes in 30/75 patients, including 12/32 patients in which surgical treatment was previously planned, and progression free survival time was significantly longer in these patients.

Clinical value of immunoscintigraphy in the rectal carcinomas: immunoscintigraphy of rectal carcinomas.

BACKGROUND/AIM: The aim of this study was to evaluate the clinical reliability of the immunoscintigraphy with radiolabeled monoclonal antibodies for the detection of metastases and recurrences of rectal carcinomas. METHODOLOGY: A total of 65 patients underwent immunoscintigraphy with radiolabeled monoclonal antibodies. Indication for that examination was suspicious rectal cancer or suspicious rectal cancer recurrence and/or metastases. RESULTS: The method proved to have 92.7% sensitivity, specificity 83.3%, positive predictive value 90.5%, negative predictive value 87.0% and accuracy 89.2%. There was a statistically significant relationship between immunoscintigraphy findings and rectoscopy findings (rs=0.415, p=0.013), as well as significant relationship between immunoscintigraphy findings and US findings (rs=0.332, p=0.001). Tumor marker levels were in positive correlation with findings of immunoscintigraphy (rs=0.845, p=0.001), especially raised CEA level (rs=0.816, p=0.004). Patients with higher CA19-9 level had higher Duke's stage (p=0.025). CONCLUSIONS: We can conclude that immunoscintigraphy can be helpful in the detection of metastases and recurrences of colon carcinomas.

Gallbladder motility disorders estimated by non-invasive methods.

BACKGROUND/AIMS: The aim is to compare the radionuclide (DC) and ultrasonographic (US) method in the assessment of gallbladder (GB) motility. METHODOLOGY: The study was performed in 15 controls (C), 10 patients with acute cholecystitis (AC), 20 patients with chronic acalculous cholecystitis (CAC), 26 patients with chronic cholecystitis with calculosis (CCC) as well as in 15 patients with GB dyskinesia (D). GB emptying period (EP), ejection fraction (EF) and ejection rate (ER) were estimated with dynamic cholescintigraphy (DC) and US. RESULTS: The DC and US finding in the patients with AC was typical in all the patients, i.e. GB was not visualized at all on DC, while on US, stone was visible in the cystic duct. There were significant differences (p<0.05) between the EF and ER values obtained between C and the three groups of patients CAC, CCC and D, using both methods. However, there were no significant differences in EF, EP and ER values among CAC, CCC and D (p>0.05). There was also high correlation between the results obtained with both methods in all the groups of patients studied. CONCLUSIONS: The results obtained by both methods are valuable for the assessment of GB motility. Although there are no significant differences and there is a high correlation between the values, radionuclide method is more precise, because it can register motility continuously.

Dopamine transporter imaging (123)I-FP-CIT (DaTSCAN) SPET in differential diagnosis of dopa-responsive dystonia and young-onset Parkinson's disease.

Dopa-responsive dystonia (DRD) is a genetic disorder characterized by childhood onset dystonia, dominant inheritance, diurnal symptoms fluctuation and positive levodopa response. Adult-onset DRD is frequently combined with parkinsonism and can be mistaken with young onset Parkinson's disease (YOPD). Both conditions are caused by dopamine deficiency, due to nigral cells' loss in YOPD, and due to enzymatic defects in dopamine synthesis in DRD. Single photon emission tomography (SPET) with (123)I-N--fluoropropyl-2b-carbomethoxy-3b-(4-iodophenyl) nortropane ((123)I-FP-CIT)-DaTSCAN is a sensitive neuroimaging method for the assessment of nigrostriatal dopaminergic system integrity and degeneration. Our aim was to evaluate the usefulness of (123)I-FP-CIT( DaTSCAN) SPET in the differential diagnosis of DRD and YOPD in clinical practice. Brain SPET with (123)I-FP-CIT was performed in 13 patients (7 males, 6 females), age 20-58 years, with mean age of onset of their disease, 29 years, eleven patients with early onset parkinsonian symptoms and 2 with genetically proved DRD. The images were evaluated by visual and semiquantitative analyses (ROI). The ratio of specific-striatal to non specific-occipital binding was calculated. Ten out of 11 patients with YOPD had decreased accumulation of DaTSCAN in striatum, especially in putamen, that is typical findings for Parkinson's disease. In three patients DaTSCAN was normal with symmetric tracer uptake in both striata, caudate nucleus and putamen and the diagnosis of DRD was suspected. Two patients with initial dystonic symptoms and genetically proved DRD had normal DaTSCAN. In one patient after normal DaTSCAN findings the initial diagnosis of YOPD was changed to the diagnosis of DRD. Region of interest (ROI) analyses have shown significantly lower(123)I-FP-CIT binding ratios in YOPD than in DRD in all 3 regions of interest: striatum (1.95±0.32) vs (2.76±0.10) P<0.001, putamen (1.76±0.25) vs (2.84±0.14) P<0.0001 and caudate nucleus (2.37±0.51) vs (3.27±0.14) P<0.01. In conclusion, our results indicate that DaTSCAN is an objective neuroimaging method able to distinguisch neurodegenerative disease YOPD from DRD and clarify a clinical dilemma, which is important for the treatment, prognosis and genetic counseling of patients and their families.

Diagnosis of mesh infection after abdominal wall hernia surgery - role of radionuclide methods.

BACKGROUND/AIMS: The aim of this investigation was to evaluate the role of detection of late mesh infection following incisional hernia repair with radiolabeled antigranulocyte antibodies. METHODOLOGY: Mesh infection diagnoses were set up with clinical examination and laboratory analysis and confirmed by ultrasonography (US), computerized tomography (CT), scintigraphy with 99mTc-antigranulocyte antibodies and microbiological examination. RESULTS: Of the 17 patients investigated, 6 had a late mesh infection, and 11 had both mesh infection and recurrent incisional hernia. Clear clinical signs of late mesh infection were present in 13 patients. Four remaining patients had non-specific discomfort and recurrent incisional hernia without clinical manifestation of mesh infection ('silent infection'). US was positive in 12/17 patients, CT in 13/17 patients, while scintigraphy with antigranulocyte antibodies in 17/17 patients. Therefore, sensitivity of US was 71%, of CT 76% and of scintigraphy 100%. In four patients late mesh infection was confirmed exclusively by 99mTc-antigranulocyte antibody scintigraphy, while US and CT did not indicate the infection. CONCLUSIONS: According to the present results, scintigraphy with 99mTc antigranulocyte antibodies is a useful method for the detection of 'silent' abdominal wall infections after surgery, which is very important for prompt and appropriate therapy.

Radioimmunoscintigraphy of colorectal carcinomas with 99mTc-labelled antibodies.

BACKGROUND/AIMS: The aim of the study was the evaluation of the clinical validity of immunoscintigraphy with 99mTc labeled antibodies for the detection of metastases and recurrences of colorectal carcinomas. METHODOLOGY: We examined 17 patients with colorectal carcinomas. Scintigraphy was performed with anti-CEA MoAb 99mTc-BW 431/26. RESULTS: Recurrences of carcinomas were detected and confirmed by surgery in 6 patients, recurrences with liver metastasis in 5 patients, and only liver metastases in 3 patients. Planar immunoscintigraphy was positive in 5/8 patients with liver metastases and 8/11 patients with recurrences, whereas in 1/8 liver metastases and 3/11 recurrences were detected only by tomography. In two patients with metastases in the abdominal lymph nodes immunoscintigraphic findings both on planar scintigraphy and tomoscintigraphy were false negative. CONCLUSIONS: Immunoscintigraphy with 99mTc labeled antibodies can be useful in the diagnosis of recurrences and metastases of colorectal carcinoma, viability assessment after radiotherapy and in the choice of the adequate surgical treatment.

The diagnostic role of gated myocardial perfusion imaging and radionuclide ventriculography in severe congenital heart disease.

Several techniques have been applied for the assessment of severe congenital heart diseases (SCHD) including echocardiography, cardiac catheterization with angiocardiography, and more recently, cardiovascular multi detector tomography and magnetic resonance imaging (MRI). The value of gated single photon emission tomography (GSPET) myocardial perfusion imaging (MPI) and radionuclide ventriculography (RNV) for evaluating myocardial ischemia, tissue viability, and left ventricular function in SCHD is less apparent. The risk of radiation exposure is greatest in the youngest patients. Both, GSPET MPI and RNV seem to be underutilized in pediatric clinical practice due to increased radiation exposure. We have reviewed basic and specific technical and diagnostic aspects, as well as specific clinical indications of GSPET MPI and RNV in children with SCHD in comparison with other cardiology methods. Some of our own tests are also presented where they apply. In conclusion, GSPET MPI and RNV can provide clinical relevant information of functional significance of SCHD in pediatric patients especially when the other cardiology methods are indeterminate. With regard to radiation exposure appropriate patient selection and recommendations for reduction of radiation exposure are of great importance.

Is identification of malignant lesions of the liver and of hemangiomas possible by Doppler ultrasonography and radionuclide angiography?

The aim of this study was to try to diagnose malignant liver lesions and hemangiomas by means of vascularisation and perfusion studies. The study was performed in 32 patients with hepatocellular carcinoma (HCC), in 74 with metastatic liver carcinoma (MLC) and in 40 with hemangiomas (H). Color Doppler ultrasonography (DUS) was done with an ATL Ultramark 9 apparatus with convex probe 2.5 MHz using pulse and DUS. Hepatic radionuclide angiography (HRA) was performed with bolus injection of 740 MBq (99m)Tc-pertechnetate, (1 min, 1 f/s), using ROTA scintillation camera and MicroDelta computer. Hepatic perfusion index (HPI) indicated the percentage of the portal blood inflow to the liver. Our results showed that in HCC and MLC there was a decrease of portal inflow while arterial inflow was increased resulting in pulse arterial wave velocity increase and in continuous venous waves velocity in the tumors. There was significant linear correlation between the increase of the arterial inflow and the arterial pulse wave found in the center and in the margin of the tumors. In hemangiomas, hepatic perfusion index related to arterial inflow was within normal range. In conclusion, our results suggest that HCC and MLC have specific characteristics in vascular and/or perfusion studies while hemangiomas show normal liver parenchyma findings.

Relationship between Helicobacter pylori infection estimated by 14C-urea breath test and gender, blood groups and Rhesus factor.

The aim of this study was the detection of helicobacter pylori (HP) infection and estimation of this infection relationship with age, gender, blood groups and Rhesus factor, as well as the assessment of the accuracy of the method. A total of 227 patients with gastritis were examined. Blood ABO groups and Rh positivity were determined using standard tests. Infection by HP was proved by (14)C-urea breath test and gastric biopsy. Patients were aged 20-81 years (X=51.7 years) and the presence of HP was not related to the age (P>0.05). From the total number of patients, 25/69 males and 68/158 females were HP positive. There was no significant difference between genders and HP infection (P>0.05). From the 227 investigated patients, 69 (30%) belonged to blood group O, 96 (42%) to A, 40 (18%) to B and 22 (10%) to AB. HP was detected in 27/69 patients with blood group O, 45/96 patients with blood group A, 16/40 patients with blood group B and 5/22 patients with blood group AB. There was no statistically significant difference (P>0.05) in the incidence of HP infection between these groups (proving that HP infection did not depend upon the blood groups). Also, there was no significant correlation between the presence of particular blood group in HP+ patients related to the reported frequency of the blood groups in Serbian population (0--38%, A--42%, B--15%, AB--5%). HP was found in 16/36 Rh- and in 77/191 Rh+ patients without statistical difference (P>0.05). Also, there was no significant correlation of the presence of the Rh factor in the HP positive patients to the frequency of the Rh factor in the Serbian population (84% Rh+ and 16% Rh-). The basic value of the HP+ test was slightly, but not significantly lower in comparison to the HP- patients (P>0.05). On the contrary, test values showed a highly significant difference (P<0.01) in HP+ and HP- patients. In conclusion, in adults HP infection does not depend upon the patient's age, gender, blood group type or Rh factor. In clinical terms, there were 93 true positive (TP), 129 true negative (TN), 5 false negative (FN) and 0 false positive (FP) patients. Sensitivity of the method was 94.9%, specificity 100%, positive predictive value 100%, negative predictive value 96.3% and accuracy 97.8%.

Fractional flow reserve and myocardial viability as assessed by SPECT perfusion scintigraphy in patients with prior myocardial infarction.

BACKGROUND: In patients with previous myocardial infarction (MI), assessment of myocardial viability and physiological significance of coronary artery stenoses are essential for appropriate guidance of revascularization. The aim of the study was to evaluate the relation between fractional flow reserve (FFR) and myocardial viability as assessed by gated SPECT MIBI perfusion scintigraphy in patients with previous MI undergoing elective PCI. METHODS: The study population consisted of 26 patients (mean age 55 ± 7 years; 21 male) with a previous MI and a significant coronary stenosis in a single infarct-related coronary vessel for which PCI was being performed. In all patients, FFR was evaluated before and immediately after PCI. SPECT imaging was done before and 3 ± 1 months after PCI. A region representing the MI was considered viable if MIBI uptake was ≥55% of the normal region. Improvement in perfusion after revascularization was considered achieved if perfusion abnormalities decreased by 5% or more and there was a decrease in segmental score of ≥1 in three segments in PCI-related vascular territory. RESULTS: Extent of perfusion abnormalities decreased from 32 ± 16% to 27 ± 19% after PCI (P < .001). In patients with myocardial viability in comparison to patients with no viability, there was significant difference in FFR before PCI (.57 ± .14 vs .76 ± .12, P = .002), despite almost the same values of diameter stenosis of infarct-related artery (63 ± 8% vs 64 ± 3%, respectively, P = .572). In addition, FFR prior to PCI was related to improvement in perfusion abnormalities after revascularization (P = .047), as well as with peak activity of creatine-kinase measured during previous MI (r = .56, P = .005). CONCLUSION: Lower values of FFR before angioplasty are associated with myocardial viability and functional improvement as assessed by SPECT perfusion scintigraphy.

Clinical investigations of 99mTc-p-aminohippuric acid as a new renal agent.

OBJECTIVE: 99mTc-p-aminohippuric acid (PAH) is a new radiopharmaceutical rapidly secreted by the kidneys in a manner consistent with tubular secretion. A comparative study of renal scintigraphy and clearance with 99mTc-PAH, diethylene triamine pentaacetic acid (DTPA) and mercaptoacetyltriglycine (MAG,) was performed. METHODS: 99mTc-PAH was prepared from a lyophilized kit by addition of sodium pertechnetate in the presence of DTPA. Ten healthy individuals were injected with 110 MBq of 99mTc-PAH. A dynamic study was repeated with 99mTc-DTPA and 99mTc-MAG3 several days later, after a 1-day interval. Clearance measurements were performed in five individuals. RESULTS: The mean values of time-to-peak activity (Tmax) and the time from peak to 50% of peak activity (T(1/2)) for 99mTc-PAH (3.6 +/- 0.9 and 6.9 +/- 2.7 min, respectively) and 99mTc-MAG3 (3.5 +/- 0.8 and 6.8 +/- 2.1 min, respectively) were significantly lower in comparison with those of s99mTc-DTPA (4.9 1.7 and 11.7 +/- 1.9 min, respectively). The mean value of 99mTc-PAH clearance (186.9 +/- 12.2 ml/min) was significantly lower in comparison with MAG3 clearance (303.9 +/- 19.5 ml/min) and significantly higher than DTPA clearance (85.0 +/- 24.1 ml/min). CONCLUSION: Our preliminary results indicate the potential usefulness of 99mTc-PAH for routine renal scintigraphy. Owing to its fast kinetics, excretion properties and high-quality images, it could be a suitable substitute for 99mTc-DTPA. 99mTC-PAH clearance values, however, were significantly lower than those of MAG3, and could not be used for the estimation of renal plasma flow.

Site of myocardial infarction and severity of perfusion abnormalities impact on post-stress left ventricular function in patients with single-vessel disease: gated single-photon emission computed tomography methoxyisobutylisonitrile study.

OBJECTIVES: We used gated single-photon emission computed tomography methoxyisobutylisonitrile (SPECT MIBI) to (i) determine whether location of myocardial infarction (MI) and severity of perfusion abnormalities affect post-stress left ventricular function in patients with single-vessel coronary artery disease, and (ii) correlate changes between post-stress and rest ejection fraction (EF) with the severity of perfusion and regional wall motion abnormalities (RWMAs). METHODS: Eighty-eight patients with a history (> or =3 months) of anterior MI (n=45) or inferior MI (n=43) underwent a 2-day stress-rest gated SPECT MIBI. 4D-MSPECT software was used to calculate left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), EF, and the difference from post-stress to rest EF (EFs-EFr). Summed stress scores, summed rest scores, and summed difference scores (SDS) were calculated based on the 17-segment model. RWMAs were visually assessed using a 5-point score. RESULTS: Patients with anterior MI, compared with those with inferior MI, showed significantly greater perfusion abnormalities (summed stress score 11.0+/-5.5 vs. 7.5+/-2.4, P<0.01, summed rest score 7.4+/-4.7 vs. 5.2+/-1.9, P<0.01, SDS 3.3+/-1.0 vs. 1.9+/-1.0, P<0.05) and higher post-stress and rest RWMA (RWMSS 12.2+/-6.0 vs. 8.7+/-4.1, P<0.01, RWMRS 8.7+/-5.4 vs. 5.6+/-3.0, P<0.01). In 22 patients with anterior reversible ischemia in addition to fixed defect, post-stress and rest EDV and ESV were significantly larger and post-stress EF decreased more than in 21 patients with inferior MI (EDV 144.0+/-28.9 ml vs. 108.6+/-36.9 ml, ESV 70.6+/-22.2 ml vs. 53.4+/-20.5 ml, EFs-EFr -4.2+/-3.5% vs. -1.5+/-2.2%, P<0.01). SDS and RWMA were highly correlated with EFs-EFr. CONCLUSION: In patients with single-vessel coronary artery disease, the extent and severity of perfusion and RWMAs assessed by gated SPECT MIBI are greater after anterior MI than inferior MI. Global left ventricular function is significantly more affected after anterior MI only in patients with reversible ischemia in addition to fixed wall defect. Decrease in EF from post-stress to rest is closely associated with the severity of perfusion and RWMAs. Overall results suggest that the extent and severity of perfusion and RWMAs are more prominent in the myocardial region supplied by left anterior descending coronary artery than by right coronary artery, which may explain significantly worse post-stress left ventricular function after anterior MI.

One-year follow-up of myocardial perfusion and function evaluated by gated SPECT MIBI in patients with earlier myocardial infarction and chronic total occlusion.

OBJECTIVE: Optimal treatment for chronic total occlusion (CTO) in the infarct-related coronary artery is not clear. Our aim was to assess myocardial perfusion, left ventricular ejection fraction (EF), and left ventricular size using gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging with 99mTc-methoxy-isobutyl-isonitrile in patients with CTO before and 1 year after recanalization. METHODS: Thirty patients with earlier myocardial infarction and at least one CTO underwent percutaneous coronary intervention (PCI) as well as nitrate-enhanced gated SPECT myocardial perfusion and dobutamine stress echocardiography before and 11 +/- 1 months after recanalization. They were divided into three groups based on the outcome of the follow-up angiography: (i) successful recanalization with no evidence of in-stent restenosis (n=13); (ii) successful recanalization with in-stent restenosis (n=7) and (iii) unsuccessful recanalization (n=10). RESULTS: Overall success of recanalization for CTO was 74%. In group 1, myocardial viability was preserved in 11 of 13 (85%) patients at baseline. Gated SPECT at 1 year showed a significant decrease in perfusion abnormalities (29 +/- 12 to 23 +/- 14%, P < 0.05) and left ventricular end-diastolic volume (EDV) (168 +/- 47 to 151 +/- 47 ml, P < 0.05). Improvement in EF (51 +/- 11 to 54 +/- 13%, P > 0.05) and reduction in left ventricular end-systolic volume (ESV) (84 +/- 37 to 77 +/- 40 ml, P > 0.05) did not reach the level of significance. Myocardial viability was preserved in only two of seven patients (28%) in group 2. Neither mean perfusion abnormalities (37 +/- 24 to 35 +/- 22%, P > 0.05) nor global left ventricular parameters (EF 41 +/- 15 vs. 42 +/- 19%, EDV 298 +/- 33 vs. 299 +/- 57 mL, ESV 197 +/- 12 vs. 195 +/- 32 ml; P > 0.05) changed at the follow-up. In group 3, myocardial viability was preserved in seven of 10 patients (70%) at baseline, but no significant changes in perfusion (40 +/- 18 vs. 41 +/- 19%, P > 0.05) and left ventricular function (EF 42 +/- 17 vs. 44 +/- 14%, EDV 228 +/- 101 vs. 227 +/- 81 ml, ESV 143 +/- 87 vs. 146 +/- 8 ml; P > 0.05) were seen at the follow-up. CONCLUSION: Myocardial perfusion and EDV may significantly improve 1 year after PCI provided recanalization of CTO was successful. Our preliminary findings suggest that successful recanalization of CTO may have favorable outcome on left ventricular perfusion and function, particularly in patients with viable myocardium before PCI. The gated SPECT myocardial perfusion imaging with 99mTc-methoxy-isobutyl-isonitrile may be useful for monitoring long-term functional outcome of PCI in patients with CTO.

Detection of gastrointestinal and abdominal infections by 99mTc-antigranulocyte antibodies.

BACKGROUND/AIMS: The aim of the study was detection of abdominal infections by 99mTc- antigranulocyte antibodies. METHODOLOGY: Total of 36 patients with clinical suspicion on abdominal or gastrointestinal infections was investigated. RESULTS: There were 23 true positive (TP) findings (one pulmonary abscess, 2 subhepatic abscesses after surgery, 2 perianal fistula, 2 chronic and 4 acute appendicitis, 5 abdominal and 3 pelvic abscesses, 3 M. Crohn, one ulcerative colitis), 9 true negative (TN) (3 tumors of the coecum, 2 tumors of papilla Wateri, 2 gastric carcinoma, 2 colon carcinoma), and 4 false negative (FN) (2 abscesses subphrenic and 2 enterocolic fistula). False positive (FP) findings were not observed. The smallest lesion found was 19x18 mm. SPECT increased the number of TP findings from 17 to 23. Fifteen of 23 infectious of inflammatory lesions could be detected in the early scan. Sensitivity was 85%, specificity 100%, positive predictive value 100%, negative predictive value 69% and accuracy 89%. CONCLUSION: According to the present results, scintigraphy with 99mTc antigranulocyte antibodies is a useful method for detection and assessment of exact localization abdominal infections, which is very important for the prompt and appropriate therapy.

Assessment of non-small cell lung cancer viability and necrosis with three radiopharmaceuticals.

UNLABELLED: Assessment of tumor viability and necrosis of non-small cell lung cancer and detection of distant metastases are important for diagnosis, staging, monitoring the response to treatment and planning long-term management. We performed scintigraphy on patients with non-small cell lung cancer to determine the utility of three tumor targeting tracers for diagnosing primary lung cancer, for differentiating viable from necrotic tumor tissue and for detecting distant bone and soft tissue metastases. Our patients were divided into groups. Group A consisted of 27 patients, 25 male and 2 female, mean age 59 years, range from 35 to 72 years. These patients underwent radioimmunoscintigraphy (RIS) using monoclonal antibody against human milk fat globule labeled with technetium-99m ((99m)Tc). Group B consisted of 23 patients, 21 male and 2 female, mean age 56 years, range: 37 to 70 years. Group C consisted of 24 patients, 20 male and 4 female, mean age 58 years, range: 35 to 74 years. Both Groups B and C underwent chest and whole-body scintigraphy with 555 MBq of (99m)Tc-sestamibi ((99m)Tc-S) and 111 MBq of thallium-201 chloride ((201)TlCl), respectively. Tumor to non-tumor ratio was calculated. Our findings show that RIS had 52% sensitivity in detecting primary non-small cell lung cancer. In contrast, the sensitivity of (99m)Tc-S and of (201)Tl scintigraphy was 87% and 88%, respectively. High uptake of all three radiopharmaceuticals was found in 6 patients with distant soft tissue and bone tissue metastases and in 1 patient with brain metastasis. Mean tumor to non-tumor ratios were similar: for RIS 1.7+/-0.4, for (99m)Tc-S 1.6+/-0.3 and for (201)Tl 1.6+/-0.2. IN CONCLUSION: (99m)Tc-S and (201)Tl scintigraphy are superior to RIS for detecting non-small primary lung cancers and potentially clinically useful methods for detecting primary lung cancer as above, as well as bone and soft tissue metastases.

Evaluation of undifferentiated carcinoma of nasopharyngeal type with thallium-201 and technetium-99m MIBI SPECT.

OBJECTIVE: To determine the value of 201-thallium (201-Tl) and technetium-99m sestamibi (Tc-99m MIBI) single photon emission computed tomography (SPECT) for detecting primary undifferentiated carcinoma of nasopharyngeal type (UCNT), residual/recurrent tissue, and lymph node involvement. STUDY DESIGN AND SETTING: SPECT of head and neck was prospectively performed in 46 patients with a history of UCNT (201-Tl in 24 patients, Tc-99m MIBI in 22). CT/MRI findings, clinical follow-up, and pathohistological verification served as a gold standard for calculating sensitivity, specificity, and accuracy of each scintigraphic technique. Tumor-to-background index (T/Bg) was derived when SPECT findings were positive. RESULTS: Sensitivity of 201-Tl SPECT was 87 percent, with 78 percent specificity, 83 percent accuracy, and T/Bg of 4.05 +/- 1.50. Tc-99m MIBI SPECT had 85 percent sensitivity, 78 percent specificity, 82 percent accuracy, and T/Bg of 4.45 +/- 1.27. CONCLUSION AND SIGNIFICANCE: 201-Tl SPECT and Tc-99m MIBI SPECT are useful for detecting primary UCNT, residual/recurrent disease, and lymph node involvement. This use is particularly valuable after chemoradiotherapy when CT/MRI may be ambiguous.

Hepatic radionuclide angiography and Doppler ultrasonography in the detection and assessment of vascular disturbances in the portal system.

BACKGROUND/AIMS: The aim of the study was evaluation of the morphology of the blood vessels, blood flow velocity and direction with Doppler ultrasound (D-US) and correlation with the relative liver parenchymal perfusion assessed by hepatic radionuclide angiography (HRA). METHODOLOGY: Real-time, D-US and HRA were performed in 108 patients. RESULTS: In patients with portal venous aneurysm, hepatopetal blood flow was increased, while portal perfusion did not differ from controls. In portal hypertensive patients, D-US detected dilatation of the portal system veins, with decreased blood flow. In comparison to the portal perfusion in controls and portal venous aneurysm, 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, sclerosed esophageal varices, recanalized umbilical vein, partial portal thrombosis and cavernous portal vein with hepatofugal, hyperkinetic or slow blood flow, and very low velocities beside the thrombi, portal perfusion was lower (p < 0.01) than in controls, portal venous aneurysm, chronic active hepatitis and liver cirrhosis without collaterals. In complete thrombosis, minimal collateral flow was found with D-US, while HRA proved no portal supply. CONCLUSIONS: D-US and HRA are complementary for the estimation of various liver vascular disorders.

Immunoscintigraphy of colorectal carcinomas with radiolabeled monoclonal antibody fragments.

BACKGROUND/AIMS: The aim was evaluation of the accuracy and clinical impact of the immunoscintigraphy for the detection of metastases and recurrences of colorectal carcinomas using two different radiolabeled antibody fragments. METHODOLOGY: The study was performed in 5 patients with IMACIS 1 containing the cocktail of 111MBq 131I MoAb 19-9 F(ab')2 and MoAb anti-CEA F(ab')2 and 8 patients with INDIMACIS 19-9 containing 150MBq of 111In-labeled MoAb 19-9 F(ab')2. RESULTS: With IMACIS 1, in all the patients, both tumor marker values were elevated. The number of TN was 3/5 and TP 2/5. From 2 TP, one had recurrence of the diseases with peritoneal carcinosis and one with liver metastases. In one patient, the results influenced the therapeutical management. With INDIMACIS 19-9, there were 2/8 TN, with borderline value of CEA and CA 19-9. TP were 6/8 (all with elevated tumor marker values, five of them many times; 3 with recurrences, 1 with recurrence and liver metastases and two with only liver metastases. In three patients, immunoscintigraphy influenced patient management. CONCLUSIONS: With both radiopharmaceuticals, immunoscintigraphy significantly influenced the patient management or it was complementary. It would be performed in the detection of recurrence, assessment of viability and follow-up of the therapy.

Simultaneous dynamic study of gastric emptying and changes of serum levels of gut hormones in patients after peptic ulcer surgery.

BACKGROUND: The aim was to examine the influence of different modalities of peptic ulcer surgery on the gastric emptying (GE) pattern and related serum level changes of selected gut hormones. MATERIAL AND METHODS: Fifty eight subjects were examined. In 48 of them peptic ulcer surgery was performed at least six months before the examination: Billroth I (B1) in 11, Billroth II (B2) in 16, B1 with the selective vagotomy--Harkins 1 (H1) in 9 and B2 with the selective vagotomy--Harkins 2 (H2) in 12. Ten healthy volunteers (C) were also examined. RESULTS: The results of gastric emptying showed that the lag phase duration was inversely related to the GE rates, and the GE pattern was linear in both controls (C) and in operated patients, except in B2 group, in which the GE pattern was exponential. In comparison with C group, GE was slower in B1, H1 and H2 groups, and faster in B2 group. The plasma gastrin values in C group, showing two peaks, were higher in relation to other groups. In relation to C group, higher values of motilin were obtained in patients after the selective vagotomy. The plasma somatostatin values recorded in B1 and H1 groups, showing the marked peaks, were higher in relation to C group. In relation to C group the highest plasma neurotensin values were obtained in B2 group. CONCLUSIONS: In order to understand entirely the influence of peptic ulcer surgery on the GI function, further research of the role of specific hormones and neuropeptides is needed, which would enable more precise selection of the therapy in order to prevent postvagotomy and postgastrectomy syndromes.