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E K Pauwels

Publications and source records attributed to E K Pauwels.

At least 19 recordsLinked to original sources

Iodine-123 labelled radiopharmaceuticals and single-photon emission tomography: a natural liaison.

Most nuclear medicine departments possess one or more imaging apparatuses for single-photon emission tomography (SPET). Molecules of biological interest to assess metabolism and receptor function are often labelled with 123I, which allows proper SPET imaging. The various methods for radiolabelling are reviewed. As the biological integrity of these agents has been demonstrated for numerous radiopharmaceuticals, the purpose of this review is to summarize the efficacy in various fields of medicine, including the imaging of tumours, infection, myocardium and cerebrum.

Animals

Inflammatory bowel disease activity assessment using technetium-99m-HMPAO leukocytes.

Aim of the study was to evaluate [99mTc]hexamethyl-propylamine-oxime (HMPAO) leukocyte scintigraphy for the assessment of disease activity and extent in inflammatory bowel disease patients. Results and scores of scintigraphy using [99mTc]HMPAO-labeled leukocytes were retrospectively compared with the activity index of van Hees, laboratory parameters, and gastroenterologists' assessment of disease using endoscopy, radiology, and histology plus clinical parameters in 136 patients with Crohn's disease (115) and ulcerative colitis (21) and in 29 controls. There were 114 positive and 22 negative [99mTc]HMPAO leukocyte scintigrams. Sensitivities for active disease at 1 and 3 hr were 98% and 98% and specificities were 100% and 83%, respectively. [99mTC]HMPAO leukocyte scintigraphy is superior to the activity index and the gastroenterologists' clinical assessment of active inflammation in IBD patients. Scintigraphy allows assessment of the existence, extent, and intensity of active inflammation in IBD patients in one examination with high accuracy.

Adolescent

Myocardial SPET imaging with 99Tcm-tetrofosmin in clinical practice: comparison of a 1 day and a 2 day imaging protocol.

99Tcm-tetrofosmin is a new myocardial perfusion agent with the advantage that it can be reconstituted at room temperature. Because two separate injections are required for rest and stress images, a separate-day imaging protocol with one injection each day would be optimal in terms of image quality. From the logistical point of view, a 1 day protocol may be more convenient for the majority of those referred as outpatients. The main aim of this study was to determine whether the detection of myocardial ischaemia would be impeded by the use of a 1 day protocol instead of a 2 day protocol. A secondary aim was to establish the relative diagnostic accuracy of the two imaging strategies. 99Tcm-tetrofosmin SPET imaging was performed in 157 patients. Sixty-nine (44%) patients were administered 250 MBq (7 mCi) 99Tcm-tetrofosmin at rest followed 4 h later by 750 MBq (21 mCi) during stress (the 1 day protocol), whereas 88 (56%) patients had rest and stress imaging studies on two separate days, receiving a 500 MBq (14 mCi) dose of 99Tcm-tetrofosmin on each occasion (the 2 day protocol). With the 1 day protocol, 135 of 621 (22%) abnormal segments (i.e. both reversible and persistent defects) were observed, compared with 195 of 792 (25%) segments with the 2 day protocol. Also, the occurrence of reversible defects only did not differ between the two protocols (both 9%). The sensitivity for the detection of coronary artery disease was 83 and 90% for the 1 and 2 day protocols respectively. We conclude that the 1 and 2 day protocols provide similar scintigraphic information and are equally sensitive and specific for the detection of coronary artery disease. Therefore, the imaging protocol can be adjusted as appropriate for the patient in question.

Adult

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

Rapid mobilization of hematopoietic progenitor cells in rhesus monkeys by a single intravenous injection of interleukin-8.

Interleukin-8 (IL-8) is a chemoattractant cytokine involved in chemotaxis and activation of neutrophils. Because in vivo administration of IL-8 induces mobilization of hematopoietic stem cells in mice, we assessed the mobilizing properties of IL-8 in rhesus monkeys. Recombinant human IL-8 was administered as a single intravenous injection at doses of 10, 30, and 100 micrograms/kg to rhesus monkeys (age, 2 to 3 years; weight, 2.5 to 4.5 kg). Venous blood samples were obtained at time intervals ranging from 1 to 480 minutes after IL-8 administration. Cell counts, colony-forming unit-Mix assays, and fluorescence-activated cell sorter analysis were performed. Plasma was harvested to assess IL-8 levels. A time-controlled bolus intravenous injection of 100 micrograms IL-8 per kilogram of body weight resulted in peak IL-8 plasma levels up to 5 micrograms/mL. The calculated half-time life of free IL-8 was 9.9 +/- 2.2 minutes. IL-8 injection resulted in instant neutropenia that was due to pulmonary sequestration, as shown using 99mTc-labeled leukocytes. Within 30 minutes after IL-8 injection, neutrophilia developed with counts up to 10-fold greater than baseline levels. The numbers of hematopoietic progenitor cells (HPCs) increased from 45 +/- 48/mL to 1,382 +/- 599/mL of blood at 30 minutes after injection of 100 micrograms IL-8 per kilogram of bodyweight (mean +/- SD, n = 8). Individual animals showed 10- to 100-fold increase in numbers of circulating HPCs that returned to almost pretreatment values (92 +/- 52 CFU/mL) at 240 minutes after the injection of IL-8. Immunophenotyping showed no significant changes in lymphocyte (sub)populations. A second bolus injection of IL-8 with an interval of 72 hours resulted in similar numbers of mobilized stem cells as observed after the first injection, showing that no tachyphylaxis had occurred. We conclude that IL-8 induces mobilization of HPCs from the bone marrow of rhesus monkeys in a rapid and reproducible fashion. Therefore, IL-8 may be a potentially useful cytokine in the setting of blood stem cell transplantation.

Animals

Increased bone mass with pamidronate treatment in rheumatoid arthritis. Results of a three-year randomized, double-blind trial.

OBJECTIVES: Osteoporosis is a frequent complication of rheumatoid arthritis (RA). We therefore investigated the effect of oral pamidronate therapy as a specific bone-sparing agent in RA. METHODS: The study design was a 3-year randomized, double-blind trial of 300 mg oral pamidronate/day compared with placebo in 105 RA patients. Bone mineral density (BMD) measured at 12-month intervals was the primary efficacy parameter. RESULTS: In 3 years, lumbar spine and forearm BMD increased significantly in the pamidronate-treated group (by 8.4 +/- 6.9% [mean =/- SEMI] [P < 0.00011 and 5.2 =/- 6.5% [P < 0.005], respectively), compared with nonsignificant changes in the placebo-treated patients (increase of 0.6 =/- 5.2% and decrease of 1.2 =/- 5.8%, respectively). Femoral neck BMD increased in the pamidronate-treated group (by 2.6 =/- 8.6%) and decreased significantly in the placebo-treated group (by 4.0=/- 1.3% [P < 0.005]). The changes in BMD with time at all 3 measurement sites were significantly different between the treatment groups (P < 0.0001). Changes in radiographic signs of joint damage and in disease activity were similar in the 2 groups. CONCLUSION: The present study provides the first evidence that long-term treatment with an orally administered bisphosphonate overcomes bone loss and increases bone mass when compared with placebo. This finding may have significance with regard to the treatment of patients with RA.

Adult

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

Technetium, the missing element.

The history of the discovery of technetium is reviewed within the framework of the discovery and production of artificial radioactivity in the twentieth century. Important elements of this history are the accidental production of this element in a cyclotron in Berkeley, California, USA, a machine devised by Ernest Orlando Lawrence, and its subsequent discovery in 1937 by Carlo Perrier and Emilio Segrè in scrap metal parts sent by Lawrence to Palermo, Italy by mail. A detailed account is given of the steps taken; the history of the later discovery of the technetium-99m isotope in 1938 is likewise examined. Sources of natural and artificial technetium are briefly discussed.

Cyclotrons

The diagnostic utility of somatostatin receptor scintigraphy in oncology.

Somatostatin receptor scintigraphy (SRS) with the diethylenetriaminopentaacetic-acid-conjugated somatostatin analogue [111In-DTPA-D-Phe1] octreotide, also known as 111In-pentetreotide, is a new non-invasive modality for the evaluation of tumours that express receptors for somatostatin. These receptors are present on neuroendocrine and other tumours, including lymphomas and some breast cancers. In oncology SRS is a promising diagnostic tool for localizing primary tumours, staging, control and follow-up after therapy, and for identification of patients who may benefit from therapy with unlabelled octreotide or, in the future, with radiolabelled octreotide. In the past few years many small and large studies investigating various aspects of SRS have been reported. In this review the value of SRS in the management of individual tumour types is explored. For many tumours the best sensitivity in lesion detection is only achieved by very careful imaging after the administration of at least 200 MBq 111In-pentetreotide. On the basis of the current experience the main value of SRS in oncology is in the staging and evaluation of gastroenteropancreatic tumours, paragangliomas, small-cell lung cancer and lymphomas. Promising areas for SRS are the evaluation of breast cancer, non-medullary thyroid cancer and melanoma, and initial results with targeted radionuclide therapy using radiolabelled octreotide have been reported.

Amino Acid Sequence

Clearance of thallium-201 from the peripheral blood: comparison of immediate and standard thallium-201 reinjection.

As several reinjection procedures have shown encouraging results in terms of imaging, we investigated whether the kinetics of thallium-201 would differ between the standard stress-redistribution-reinjection approach and the stress-immediate reinjection approach. In 53 consecutive patients with undiagnosed chest pain, 75 MBq (2 mCi) 201Tl was injected at maximal exercise. In 26 of these patients (group I), 37 MBq (1 mCi) 201Tl was reinjected immediately after completing the exercise images (the immediate reinjection procedure) and in 27 patients (group II), 37 MBq (1 mCi) 201Tl was reinjected after completing 3-h redistribution images (the standard reinjection procedure). Mean peak 201Tl blood activity after exercise was 17.7+/-12.5 kBq/ml (4.8+/-3.4 mCi/ml) for group I versus 16.4+/-9.2 kBq/ml (4.4+/-2.5 mCi/ml) for group II (NS). The relative increase in 201Tl blood activity after reinjection of half the initial dose [37 MBq (1 mCi)] exceeded 50% of the initial peak in both groups. The relative amount of 201Tl delivered to the myocardium was assessed by the area under the curve after both exercise and reinjection, and was 117%+/-72% for group I and 112%+/-73% for group II (NS). Blood clearance of 201Tl was at least biexponential. Mean early decay constants (lambda 1) after exercise and reinjection were 0.30+/-0.18 min-1 and 0.22+/-0.046 min-1 respectively for group I (T 1/2 2.3 min and 3.2 min respectively, NS), and 0.30+/-0.12 min-1 and 0.24+/-0.07 min-1 respectively for group II (T1/2 2.3 min and 2.9 min respectively, NS). For both procedures no significant differences were found between lambda 1 after exercise and lambda 1 after injection. The mean late clearance (lambda 2) from the blood was 0.032+/-0.056 min-1 and 0.012+/-0.012 min-1 respectively for group I (T1/2 21.6 min and 57.7 min respectively, NS), and 0.036+/-0.030 min-1 and 0.014+/-0.014 min-1 respectively for group II (T1/2 19.3 min and 49.5 min respectively, NS). Also, no significant differences were found between lambda 2 after exercise for both groups and between lambda 2 after reinjection for both groups. We conclude that reinjection of 37 MBq (1 mCi) 201Tl (half the initial dose) results in a relative increase in the initial peak and a relative increase in the amount of 201Tl delivered to the myocardium of more than 50% for both the standard and the immediate reinjection procedure. The clearance of 201Tl from the blood was not influenced by exercise or by the time of reinjection. Based on 201Tl kinetics as measured in the peripheral blood, there is no reason to postpone reinjection until 3-4 h following exercise.

Angina Pectoris

Defect reversibility using thallium-201 reinjection. Comparison of stress-redistribution-reinjection with stress-immediate reinjection.

Immediate poststress thallium-201 reinjection followed by imaging one hour later has been proposed as an alternative reinjection protocol. This procedure is patient-convenient and time-saving as it shortens the investigation time to maximally 2.5 hours. The efficacy of the immediate thallium-201 reinjection protocol was assessed in 305 patients with stress perfusion defects in whom we compared the scintigraphic findings of 210 consecutive patients who underwent the standard thallium-201 stress/redistribution/reinjection protocol (Group I), with 95 consecutive patients who subsequently underwent the thallium-201 stress/immediate reinjection protocol (Group II). In all patients three-view planar images were visually and quantitatively analyzed. In Group I, defect reversibility was observed in 433 of 622 (70%) stress perfusion defects compared to 220 of 320 (69%) segments in Group II (p = NS). With respect to Q-wave related segments, defect reversibility was seen in 102 of 172 (59%) segments in Group I compared to 34 of 63 (54%) in Group II (p = NS). Based on defect reversibility, the diagnosis of myocardial ischemia was made in 184 of 210 (88%) patients Group I compared to 86 of 95 (91%) patients in Group II (p = NS). These findings indicate that immediate thallium-201 reinjection imaging provides at least similar data on defect reversibility as the standard thallium-201 stress/redistribution/reinjection approach. In practical terms, the stress/immediate reinjection approach seems advantageous as it reduces imaging time, enhances patient throughout and can be considered as one comprehensive imaging procedure.

Case-Control Studies

Role of 67Ga scintigraphy in localization of lymphoma.

This review deals with the applications of 67Gallium (Ga) scintigraphy for the initial staging and follow-up during and after treatment of patients with Hodgkin's or non-Hodgkin's lymphoma (NHL). During the last decade, the technique of visualization has been largely improved by using higher doses and additional tomography. Here, the indications for 67Ga scintigraphy in comparison with CT and MRI are discussed. The conditions resulting in false positive and false negative results have been outlined. 67Ga may detect unusual involved sites during staging procedures. However, the major contribution to the management of Hodgkin's disease and NHL is the evaluation of residual masses, because 67Ga uptake reflects the metabolic activity of the tumor. The review ends with an additional short overview of other radionuclide imaging methods useful for malignant lymphoma.

Gallium Radioisotopes

99Tcm-HIG accumulates in the synovial tissue of rats with adjuvant arthritis by binding to extracellular matrix proteins.

Our objective was to investigate the mechanism of accumulation of 99Tcm-labelled non-specific polyclonal human immunoglobulin (99Tcm-HIG) in inflamed synovial tissue (ST) in an experimental animal model of arthritis. Following 99Tcm-HIG scintigraphy, the in vivo localization of 99Tcm-HIG in the ST of knee joints of rats with adjuvant arthritis was studied using immunohistochemical techniques. In addition, the in vitro binding of 99Tcm-HIG to extracellular matrix proteins was analysed by means of immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). After 99Tcm-HIG scintigraphy, 99Tcm-HI was detected in the ST of rats with adjuvant arthritis. 99Tcm-HIG was diffusely distributed and not bound to cells. In vitro incubation of 99Tcm-HIG on the ST of rats with adjuvant arthritis revealed binding of 99Tcm-HIG to inflamed, but not to non-inflamed, ST. In addition, specific binding of 99Tcm-HIG to fibronectin, fibrin, collagen type I and III was demonstrated by ELISA. We conclude that the accumulation of 99Tcm-HIG in inflamed ST can be explained by the binding of 99Tcm-HIG to extracellular matrix proteins.

Animals

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

Head-to-head comparison of 201Tl rest-redistribution scintigraphy and stress-immediate reinjection scintigraphy in the detection of myocardial viability.

Reinjection imaging with thallium-201 (201Tl) provides a reliable method of identifying viable myocardium. Reinjection of 201Tl immediately after completing the stress images followed by imaging 1 h after reinjection shortens the examination time to a maximum of 2.5 h and provides an alternative imaging approach in patients with coronary artery disease. In this study, we investigated whether immediate 201Tl reinjection imaging provides adequate information on myocardial viability compared with separate-day 201Tl rest or rest-redistribution imaging. In 23 patients with anterior or anteroseptal wall infarction first documented more than 3 months previously, we performed 201Tl stress-immediate reinjection, separate-day 201Tl rest imaging and rest-stress radionuclide angiography. In 13 patients, 201Tl rest scintigraphy was followed by redistribution imaging 3 h later. On the three-view planar 201Tl images, eight myocardial segments were analysed visually and quantitatively. Stress 201Tl images were compared with 201Tl reinjection images, 201Tl rest images and 201Tl 3-h redistribution images after rest injection. When comparing the stress images both with the immediate reinjection images and the rest images, concordant scintigraphic classification was found in 181 of 184 myocardial segments (kappa = 0.97). Comparing the stress images both with the immediate reinjection images and with the 3-h redistribution images following 201Tl injection at rest, concordant scintigraphic classification was found in 102 of 104 myocardial segments (kappa = 0.97). In 16 of 23 (70%) patients, 201Tl stress-immediate reinjection scintigraphy and radionuclide angiography provided concordant information on myocardial viability. In 6 (26%) patients, we observed a function-perfusion mismatch (i.e. 201Tl uptake in dyskinetic/adyskinetic regions) indicative of jeopardized but viable myocardium, demonstrating the additional value of 201Tl as a marker of viability. We conclude that stress-immediate 201Tl reinjection images provide information on myocardial viability and ischaemia in patients with previous myocardial infarction in addition to that obtained regarding wall motion abnormalities as assessed by rest-stress radionuclide angiography.

Adult

Quantitative analysis of defect reversibility after immediate and standard 201Tl reinjection.

Immediate reinjection of 201Tl after exercise imaging has been proposed as a time-saving approach for the accurate distinction between ischaemic and scarred myocardium. However, with this procedure, defect reversibility may be underestimated due to the high level of residual 201Tl activity in normally perfused myocardium at the time of reinjection. The aim of this study was to determine whether the detection of defect reversibility is hampered by a shortening of the time interval between exercise and reinjection. In 53 patients, 201Tl was injected, at the point of maximal exercise. In 26 patients, 201Tl was reinjected immediately after exercise imaging (Group I); in 27 patients, 201Tl was reinjected after 3 h redistribution imaging (Group II). In all patients (424 myocardial segments), three-view planar images were analysed quantitatively. Changes in myocardial activity after 3 h redistribution and reinjection were compared with the post-exercise images. In normal segments, the relative change in 201Tl activity after reinjection was 8.8 +/- 19.9% in Group I and -19.7 +/- 19.5% in Group II (P < 0.05). In Group I, persistent defects showed a relative change of 14.3 +/- 25.1% and reversible defects a relative change of 36.3 +/- 41.6% (P < 0.05). In Group II, persistent defects showed a relative change of -15.1 +/- 18.3% and reversible defects a relative change of 2.4 +/- 25.2% (P < 0.05). Our results indicate that shortening the time interval between exercise and reinjection has no effect on the detection of ischaemia.

Adult

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