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J F Verzijlbergen

Publications and source records attributed to J F Verzijlbergen.

At least 19 recordsLinked to original sources
PubMed2007

The intra-articular distribution of 90yttrium does not influence the clinical outcome of radiation synovectomy of the knee.

OBJECTIVES: To assess the impact of the intra-articular distribution of (90)yttrium-citrate ((90)Y) on the clinical effect of radiosynoviorthesis (RSO) of the knee and on (90)Y leakage from this joint. METHODS: Patients with arthritis of the knee received 185 MBq (90)Y combined with a glucocorticoid, followed by clinical bed rest. Intra-articular (90)Y distribution, measured with a dual-head gamma camera immediately or after 24 hours, was scored as mainly diffuse or mainly focal. Leakage to regional lymph nodes, the liver and spleen was assessed with a dual-head gamma camera after 24 hours. Clinical effect was scored after 6 months by a composite change index (CCI), range 0-12; responders were defined as having a CCI > or =6. RESULTS: Seventy-eight knees of 69 patients, mostly suffering from undifferentiated arthritis (42%) or RA (28%), were treated. (90)Y distribution was mainly diffuse in 54% and mainly focal in 46% with clinical response rates of 40% versus 56%, respectively, p = 0.3. CCI was not correlated with distribution. (90)Y leakage was found only to the liver and the spleen (mean leakage 0.4% and 1.1%, respectively). Leakage was significantly less in case of diffuse intra-articular (90)Y distribution, whereas leakage to the liver was correlated with distribution (r = 0.68, p<0.001). (90)Y leakage was not correlated with CCI. CONCLUSIONS: Intra-articular (90)Y distribution does not influence the clinical effect of RSO of the knee. Although (90)Y leakage from the joint is less if (90)Y distributes diffusely in the joint cavity, leakage does not seem to hamper the clinical effect.

Adult↗
PubMed1997

SPECT versus planar 99mTc-sestamibi myocardial scintigraphy: comparison of accuracy and impact on patient management in chronic ischemic heart disease.

A head-to-head comparison between 99mTc-sestamibi SPECT and planar myocardial imaging using dipyridamole low-level exercise stress was performed for the assessment of coronary artery disease (CAD) and for the impact on patient management in 78 patients (pts) who underwent coronary arteriography. Overall sensitivity and specificity for detection of CAD were 82% and 82% for SPECT, and 78% and 73% for planar imaging, respectively (both NS). Compared to planar imaging the sensitivity of SPECT imaging was significantly higher for detecting left anterior descending (p = 0.02) and left circumflex (p = 0.03) coronary artery disease. In predicting distally located stenoses, SPECT was significantly superior to planar imaging for the left circumflex artery (p = 0.025). Concordance analysis of perfusion status showed agreement in 308 of 390 (79%) of coronary flow regions both with respect to the presence or absence of perfusion and to the reversibility or irreversibility of defects (kappa = 0.60, SE 0.04). Stress-induced perfusion defects were significantly more detected by SPECT than by planar imaging (p < 0.001). Based on SPECT findings 31 pts were proposed for revascularization compared to 30 pts based on planar imaging (NS). Overall there was agreement in 65 (83%) pts regarding treatment strategy. We conclude that in a head-to-head comparison SPECT provided improved diagnostic value compared with planar imaging. However, with respect to patient treatment, the superiority of SPECT was not always translated into improved patient management.

Adult↗
PubMed1996

Comparison of technetium-99m sestamibi left ventricular wall motion and perfusion studies with thallium-201 perfusion imaging: in search of the combination of variables with the highest accuracy in predicting coronary artery disease.

Measurements of myocardial perfusion and ventricular function are expected to provide additional information in the detection of coronary artery disease (CAD). The purpose of this study was threefold: (1) to determine to what extent technetium-99m sestamibi wall motion yields different information compared with 99mTc-sestamibi and thallium-201 perfusion; (2) to test which information unique to either study is of value in diagnosing CAD; and (3) to assess the combination of variables with the highest diagnostic accuracy. Perfusion and wall motion scores (at rest and during exercise) obtained from visual and quantitative planar 201Tl and 99mTc-sestamibi scintigraphy of 60 patients with suspected CAD were compared with the angiographic results by means of a polytomous logistic regression model and the diagnostic values were compared with one another. All univariate variables were significantly related to the probability of CAD and its extent. Comparative studies revealed a large degree of correlation between 201Tl stress and redistribution variables. The rest 99mTc-sestamibi and wall motion studies contained partially different information. Stepwise logistic regression analysis showed the strongest diagnostic power for the combination of 201Tl visual analysis of the stress images with quantitative redistribution images (sensitivity 93%, specificity 71%). The diagnostic power was similar for all combinations of visual and quantitative analyses of the exercise and redistribution images. The strongest diagnostic power of the 99mTc-sestamibi variables was the score of the diastolic stress image (sensitivity 91%, specificity 79%). Comparable sensitivity and specificity estimates were found when both optimal models were compared. Wall motion studies did not have additional diagnostic power. Although 99mTc-sestamibi wall motion studies, both at rest and during exercise, provide information in addition to the 99mTc-sestamibi or 201Tl myocardial perfusion variables, the information does not enhance the diagnostic power with regard to the prediction of CAD.

Coronary Angiography↗
PubMed1996

Comparison of adenosine and high-dose dipyridamole both combined with low-level exercise stress for 99Tcm-MIBI SPET myocardial perfusion imaging.

Intravenously administered adenosine and high-dose dipyridamole, both combined with low-level exercise stress, were compared in a head-to-head fashion using 99Tcm-methoxyisobutyl isonitrile (99Tcm-MIBI) single photo emission tomography (SPET) myocardial perfusion imaging. Thirty-nine consecutive patients who had undergone coronary arteriography underwent 99Tcm-MIBI (740 Mbq) SPET after dipyridamole (0.84 mg kg-1) and after adenosine (0.84 mg kg-1), both combined with low-level exercise (30 W load), and under resting conditions. Our results demonstrate that adenosine and dipyridamole combined with exercise have comparable haemodynamic effects, with a low incidence of side-effects. The time of recovery from the stress protocol was not significantly different: adenosine, 5.7 +/- 3.9 min; dipyridamole, 6.6 +/- 4.9 min. However, aminophylline was significantly (P < 0.05) more often administered to reverse side-effects using the dipyridamole protocol (36% of patients) compared with the adenosine protocol (8% of patients). The results of 99Tcm-MIBI SPET imaging were highly concordant and demonstrated a high diagnostic accuracy for identifying coronary artery disease (CAD). The sensitivity was 90% (95% confidence intervals 79-100%) with adenosine SPET and 93% (95% confidence intervals 84-100%) with dipyridamole SPET for identifying patients with CAD (i.e. luminal stenosis > 50%); their specificities were both 100% (95% confidence intervals 66-100%). The sensitivity of identifying angiographically diseased vessels was 81% (95% confidence intervals 70-92%) using adenosine SPET and 85% (95% confidence intervals 75-95%) using dipyridamole; the specificity for both stress modalities was 94% (95% confidence intervals 89-100%). The combination of exercise with adenosine and high-dose dipyridamole appears to be a feasible and safe method to alleviate some of the undesirable A1-receptor-mediated side-effects of adenosine. The choice of the pharmacological stress will depend on local expertise and availability.

Adenosine↗
PubMed1996

Potential for imaging cerebral amyloid deposits using 123I-labelled serum amyloid P component and SPET.

The systemic and cerebral accumulation of 123I-labelled serum amyloid P component (123I-SAP) was studied in patients with hereditary cerebral amyloid angiopathy-Dutch type (HCHWA-D) to determine the usefulness of 123I-SAP imaging in cerebral amyloidosis. Whole-body and SPET scintigraphic imaging was performed in two patients with HCHWA-D and four controls after the intraveous injection of 123I-SAP. Venous 123I-SAP clearance was also determined. Accumulation of the tracer was observed in the cerebral cortex of both patients, whereas no accumulation was seen in the controls. Blood clearance of radioactivity was similar in the patients and controls, suggesting that the amount of uptake of 123I-SAP in the cerebral amyloid deposits is relatively small. We believe this to be the first demonstration of cerebral amyloid deposits in vivo. Our findings indicate that 123I-SAP scintigraphy has possibilities for the diagnosis of patients with cerebral amyloid diseases, in addition to its use in patients with systemic amyloid deposition.

Brain↗
PubMed1994

Coronary angioplasty in a patient with situs inversus totalis and a single coronary artery.

A patient with congenital situs inversus totalis and a single coronary artery was referred for revascularization because of progressive disabling angina. Exercise thallium scintigraphy had disclosed ischaemia in the anterolateral, posterolateral, and inferior wall of the left ventricle. Percutaneous transluminal coronary angioplasty was performed successfully for stenoses in the right coronary artery.

Angioplasty, Balloon, Coronary↗
PubMed1994

Non-invasive detection of deep venous thrombosis: ultrasonography versus duplex scanning.

In a prospective study the diagnostic value of compression ultrasonography (CUS) versus Duplex scanning (DS) in the non-invasive detection of acute femoropopliteal deep venous thrombosis (DVT) was determined. In 114 eligible patients clinically suspected of DVT of the lower extremity, compression ultrasonography and Duplex scanning were performed within 24 hours by different assessors unaware of the outcome of the other test. In 109 patients concordant results of combined compression ultrasonography and Duplex scanning were obtained and considered as a proof of the absence or presence of deep venous thrombosis and no subsequent invasive investigations were performed. In five patients compression ultrasonography and Duplex scanning were discordant and contrast venography was performed. Femoropopliteal thrombosis was present in 47 legs (41%). The sensitivity, specificity and accuracy of compression ultrasonography were 93.6, 97.0 and 95.6%, respectively, and of Duplex scanning 100, 98.5 and 99.1%, respectively. We conclude that compression ultrasonography and Duplex scanning are methods with comparably high accuracy. Because of its availability, accuracy, cost-effectiveness and simplicity we recommend compression ultrasonography as the primary diagnostic test in the detection of deep venous thrombosis.

Adolescent↗
PubMed1994

Quantitative analysis of planar technetium-99m Sestamibi myocardial perfusion images. Clinical application of a modified method for the subtracton of tissue crosstalk.

Application of the Thallium-201 quantitative analysis method to Tc-99m Sestamibi planar myocardial perfusion images results in oversubtraction of tissue crosstalk, defined as 'activity within the myocardial image, which originated outside the heart'. A modified algorithm, specific for Tc-99m Sestamibi, was applied in 60 patients and the results of quantitative analysis to estimate the risk of coronary artery disease were compared with coronary angiographic findings and with visual analysis. New crosstalk planes were generated based on the results in 20 male healthy volunteers. The results in our study group indicate a higher diagnostic accuracy when circumferential profiles are generated on the basis of maximal counts compared to mean counts. Quantitative analysis was able to predict the presence or absence of CAD as accurately as visual analysis. Odds ratios were 1.07 and 1.32 respectively (P < 0.001) for both quantitative maximal uptake and visual uptake analysis. Sensitivity of visual analysis alone was 89%, increasing to 96% with combined visual/quantitative analysis. Specificity of visual analysis decreased from 79% to 64% with combined analysis. Although only minor differences are seen, the maximal count uptake profiles were found to have additional diagnostic value compared to visual analysis alone.

Adult↗
PubMed1994

99Tcm-sestamibi SPECT with combined dipyridamole and exercise stress in coronary artery disease.

In order to evaluate the clinical value of 99Tcm-methoxyisobutylisonitrile (sestamibi) single photon emission computed tomography (SPECT) after dipyridamole infusion in combination with low level bicycle exercise for the assessment of the presence, localization and extent of coronary artery disease (CAD), myocardial perfusion imaging was performed in 76 patients. Low level bicycle exercise was used to supplement the standard dipyridamole infusion protocol because of the lower incidence of non-cardiac side effects. The results were compared to arteriographic findings obtained within 3 months of the SPECT studies. The overall sensitivity of detection of coronary artery disease (i.e. a luminal stenosis > 50%) was 81%, specificity 80%, positive predictive value 96%, negative predictive value 40% and accuracy 82%. The diagnostic values for the detection of significant stenoses in the three major coronary arteries were: left anterior descending artery sensitivity 72%, specificity 87% and accuracy 76%; right coronary artery sensitivity 75%, specificity 90% and accuracy 80%; left circumflex coronary artery sensitivity 57%, specificity 85% and accuracy 71%. Scintigraphic evidence of multivessel disease was found in 31 (65%) patients with two- or three-vessel involvement assessed by arteriography. False negative test results were mainly found in patients with relatively mild CAD (one-vessel disease, branch and distal disease). 99Tcm-sestamibi SPECT after dipyridamole infusion in combination with low level bicycle exercise is shown to be a valuable diagnostic tool for the evaluation of CAD.

Adult↗
PubMed1994

Head-to-head comparison between technetium-99m-sestamibi and thallium-201 tomographic imaging for the detection of coronary artery disease using combined dipyridamole-exercise stress.

AIM: The purpose of this study was a head-to-head comparison of tomographic imaging (SPECT) with technetium-99m (Tc-99m)-sestamibi and thallium-201 (Tl-201) using dipyridamole-low-level bicycle exercise stress for the assessment of coronary artery disease. METHODS: We studied 38 consecutive patients referred for the evaluation of chest pain who had undergone coronary angiography. The patients were randomly allocated to Tc-99m-sestamibi SPECT followed by Tl-201 SPECT or vice versa. The accuracy of both tracers in detecting significant coronary artery disease (> 50% luminal stenosis) was 87% (95% confidence interval 72-96%). Only two patients were classified differently by the two methods. RESULTS: On a segmental basis, good agreement was found between Tc-99m-sestamibi and Tl-201 for both the localization and the nature of perfusion defects (reversible or persistent) identified (Cohen's kappa = 0.67). CONCLUSION: No clinically relevant differences in diagnostic accuracy were demonstrated between Tc-99m-sestamibi and Tl-201 SPECT using combined dipyridamole-exercise stress for the evaluation of coronary artery disease.

Aged↗
PubMed1992

Combined assessment of technetium-99m SESTAMIBI planar myocardial perfusion images at rest and during exercise with rest/exercise left ventricular wall motion studies evaluated from gated myocardial perfusion studies.

The favorable physical characteristics of technetium-99m-labeled 2-methoxy-2-methylisopropyl-1-isonitril (Tc-SESTAMIBI) enable the combined evaluation of both myocardial perfusion and left ventricular wall motion. To assess the potential of rest and exercise regional myocardial function as an adjunct to planar myocardial perfusion imaging, 60 patients with coronary artery disease and documented arteriographic findings were studied with both protocols during a single study. Exact segmental concordance between myocardial perfusion and wall motion studies was 77% (701/900 segments). Overall sensitivity and specificity to detect hemodynamically significant coronary artery disease with Tc-SESTAMIBI myocardial perfusion imaging were 89% and 79%, respectively, with resting wall motion studies 83% and 71%, respectively, and with rest/exercise wall motion studies, 85% and 71%, respectively. If the results of both perfusion and rest/exercise studies were combined, sensitivity increased to 96% and specificity decreased to 64%. The differences with perfusion studies alone were not statistically significant. Thus despite a good correlation between regional left ventricular function and perfusion, no statistically significant incremental diagnostic value was found when the results of both perfusion and wall motion studies were combined.

Adult↗
PubMed1991

Duplex scanning in the diagnosis of acute deep vein thrombosis of the lower extremity.

In a prospective study the value of duplex scanning in the diagnosis of acute femoro-popliteal thrombosis was compared to conventional contrast venography (CV) as a gold standard. A total of 126 legs in 117 patients suspected of having deep vein thrombosis (DVT) or pulmonary embolism (PE) were examined with both methods. CV and duplex scanning were diagnostic in 98.5 and 97%, respectively. Femoro-popliteal thrombosis was present in 64 legs (prevalence 54%). The sensitivity and specificity of duplex scanning were 90.6% and 94.6%, respectively. A marked improvement in sensitivity from 83.3 to 97% and overall accuracy from 88.7 to 96% was noticed between the first and second half of the study period. Of the individual duplex criteria in the diagnosis of DVT, abnormal vessel wall compressibility was the most accurate. The Doppler measurements however allow evaluation of venous areas difficult to assess with B-mode and add discrimination between partial or total vein occlusion. Duplex scanning is more accurate compared to CV in grading the anatomical extent of thrombosis. Agreement between venography and duplex scanning was found in 75% of the vein segments, in about 20% CV suggested more thrombus formation compared to duplex scanning. Thrombus in the deep femoral vein was documented by duplex scanning in 24 patients including two cases of isolated deep femoral vein thrombosis. Venography failed to visualise the deep femoral vein with sufficient diagnostic accuracy in 88% of the patients vs. 8.5% with duplex scanning. Duplex scanning is an accurate non-invasive test in the diagnosis of acute femoro-popliteal thrombosis and superior to CV in the detection of non-occlusive and deep femoral vein thrombosis.

Acute Disease↗
PubMed1991

99Tcm-SESTAMIBI for planar myocardial perfusion imaging; not as ideal as the physical properties.

99Tcm-methoxyisobutyl isonitrile (Tc-SESTAMIBI) has recently been introduced as a new myocardial perfusion agent which exhibits ideal physical properties for imaging with the gamma camera. To assess the diagnostic accuracy of planar Tc-SESTAMIBI, myocardial perfusion imaging was performed in 60 consecutive patients at rest and during exercise. The results were compared with coronary angiographic findings, obtained within 3 months of the exercise test. Planar 201Tl images were also performed on the same day and to the same level of stress as the Tc-SESTAMIBI exercise. Exact segmental agreement between Tc-SESTAMIBI and 201Tl was 77%. Nineteen per cent of all 900 segments demonstrated ischaemia with Tc-SESTAMIBI and 20% with 201Tl. The overall sensitivity for detecting haemodynamically significant coronary artery disease with Tc-SESTAMIBI was 86% and specificity was 78%; with 201Tl the values were 89 and 78%, respectively (differences not significant). Vessel-specific comparative detection rates revealed no statistical significant differences between both radiopharmaceuticals. Intra-observer variability for Tc-SESTAMIBI images was 12% and for 201Tl it was 14%. Inter-observer variability for Tc-SESTAMIBI was 14% and for 201Tl 17%. Although the physical characteristics of Tc-SESTAMIBI allow crisp and clear high-count density imaging, no significant differences are found when planar images are compared with 201Tl and are well within observer variabilities.

Adult↗
PubMed1991

Inadequate exercise leads to suboptimal imaging. Thallium-201 myocardial perfusion imaging after dipyridamole combined with low-level exercise unmasks ischemia in symptomatic patients with non-diagnostic thallium-201 scans who exercise submaximally.

This study was undertaken to establish the additional value of 201TI imaging after dipyridamole in combination with low-level exercise in 15 symptomatic patients with non-diagnostic 201TI scans, who exercised submaximally. Most patients had angina, ST-segment depression and even exertional hypotension and were referred for stress 201TI testing for determining the functional significance of known coronary artery disease. Six patients with a normal exercise 201TI test and one patient with an apical defect only were found to have 37 segments (of 105 segments) with reversible perfusion defects after dipyridamole infusion. One patient showing two reversible defects after exercise had five reversible segments after dipyridamole. Seven patients with fixed defects in 28 segments after exercise and two with small areas of border zone ischemia in seven additional (sub)segments, demonstrated fixed in defects in only nine segments but reversible defects in 40 segments after dipyridamole. Quantitative analysis resulted in 24.8 +/- 28.5 (mean value) sample points below -2 s.d. of the mean normal uptake after exercise, which increased to 72 +/- 26.5 after dipyridamole infusion (p less than 0.005). The washout analysis resulted in a mean value of 5.5 +/- 8.1 sample points below -2 s.d. after exercise, increasing to 33.3 +/- 22.1 after dipyridamole (p less than 0.005). Thallium-201 myocardial perfusion imaging after dipyridamole combined with low-level upright bicycle exercise may unmask scintigraphic evidence for ischemia in symptomatic patients who would otherwise have non-diagnostic imaging studies during submaximal exercise.

Coronary Disease↗
PubMed1991

Discordance of visual and quantitative analysis regarding false negative and false positive test results in thallium-201 myocardial perfusion scintigraphy.

Visual assessment and quantitative analysis of exercise thallium-201 myocardial perfusion scintigraphy was performed in 203 consecutive patients who underwent coronary arteriographic studies to identify the factors associated with false negative and false positive studies. Also the discordance between visual and quantitative analysis was evaluated. One hundred sixty-two (80%) of these 203 patients had significant coronary artery disease (CAD), i.e. a luminal stenosis greater than or equal to 50%. Fifty-two (32%) of these 162 patients with documented CAD showed negative thallium results either by visual or quantitative analysis. When interpreted visually 36/162 (22%) of patients were judged as negative, and when analyzed quantitatively 41/162 (25%) of patients were judged as negative (ns). Of the total group of 52 patients with false negative visual and/or quantitative analysis test results, 27 (17%) showed discordance between these two methods. Of the 41 patients without significant CAD, 12 (29%) showed positive thallium findings. Visual interpretation was positive in 9/41 (22%) of patients without significant CAD, and quantitative analysis in 5/41 (12%) (ns). Of the total group of 12 patients with positive visual and/or quantitative analysis test results, 10 (24%) showed discordance between these two methods. Therefore, in the total group, 37 patients (18%) showed discordance between visual and quantitative analysis. It is concluded that 1) the sensitivity and the specificity of visual interpretation and quantitative analysis of thallium-201 exercise scintigraphy for detecting CAD is similar, and 2) that there is frequent discordance of visual interpretation and quantitative analysis in thallium-201 exercise scintigraphy.

Coronary Disease↗
PubMed1990

Thallium-201 scintigraphy after dipyridamole infusion with low level exercise. II. Quantitative analysis vs visual analysis.

To determine the value and limitations of quantitative analysis of thallium-201 imaging after intravenous dipyridamole in combination with low level exercise, 81 patients with suspected coronary artery disease (CAD) were evaluated prospectively. The results of quantitative analysis were compared with the results of visual analysis. All patients underwent coronary arteriography and left ventricular angiography. Significant CAD was present in 59 patients (73%); multivessel CAD was observed in 33 patients (42%). Mild side-effects such as headache, vertigo and nausea were experienced by 12 patients (15%). To establish 'test-specific' normal limits in quantitative analysis of uptake and washout of thallium-201 after dipyridamole infusion with low level exercise we studied 20 healthy volunteers with a likelihood of CAD less than or equal to 1%. Sensitivity and specificity of quantitative analysis for overall detection of significant CAD were 76% and 73%, respectively vs 78% and 86%, respectively with visual analysis (P = NS). Sensitivity for the detection of multivessel CAD was slightly higher with quantitative analysis (73%) than with visual analysis (70%), but the specificity was lower (75% vs 92%) (P = NS). Sensitivity of quantitative analysis in relation to vessels involved was slightly lower than with visual analysis (RCA and LAD: P = NS; LCX: P less than 0.05). Of 14 patients with false-negative results, four had multivessel CAD. Thus, quantitative analysis after the combination of dipyridamole infusion with low level exercise did not improve the diagnostic value as assessed by semi-quantitative visual analysis.

Adult↗
PubMed1990

Comparative value of visual and quantitative analysis of thallium-201 imaging after exercise in patients with an abnormal baseline repolarization on the electrocardiogram at rest.

In this study the role of visual assessment and quantitative analysis of thallium-201 myocardial stress perfusion scintigraphy (MPS) was evaluated in patients with a normal electrocardiogram (ECG) (group I) and in patients with an abnormal baseline repolarization on the ECG (group II). One-hundred-and-thirty-five patients were studied. Group I consisted of 93 patients, 65 of whom had coronary artery disease (CAD), i.e. a luminal stenosis of greater than or equal to 50%; group II consisted of 42 patients, 32 of whom had CAD. In group II the exercise ECG was considered uninterpretable and thus only visual and quantitative analysis of MPS was investigated. Sensitivity and specificity of exercise electrocardiography, visual assessment and quantitative analysis of MPS were not significantly different in group I: sensitivities of the three methods were 66, 62 and 55% respectively, and specificities 86, 79 and 96% respectively. In group II there were no significant differences in the sensitivities and specificities of visual assessment or quantitative analysis of MPS: sensitivities of the two methods being both 88% and specificities both 80%. Visual assessment of redistribution (P less than 0.05) and quantitative analysis of washout (P less than 0.005) was significantly superior in group II than in group I; probably because of a higher incidence of three-vessel disease in the second group.(ABSTRACT TRUNCATED AT 250 WORDS)

Algorithms↗