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Biomedical subjects

J B van der Schoot

Publications and source records attributed to J B van der Schoot.

At least 19 recordsLinked to original sources
PubMed1993

Nuclear medicine in the monitoring of organ function and the detection of injury related to cancer therapy.

This article emphasizes the role of nuclear medicine in the monitoring of function to prevent or limit injury in organs in which toxicity related to cancer therapy may have implications for the survival and/or the quality of life of the patient. After a brief discussion of the advantages of nuclear medicine techniques in detecting organ injury, the effect of radiation therapy and chemotherapy on normal tissue is discussed, underlining the need to characterize adverse effects of cancer therapy in long-term survivors. The use of radionuclides to document organ injury and effects from cancer therapy in heart, digestive tract, kidneys, lungs, major salivary glands, skeleton and brain is then reviewed. In a short section the potential applicability of positron emission tomography in documenting organ toxicity during cancer therapy is discussed. Thanks to the various available radiopharmaceuticals, the ability of the tracers to document specific functional aspects, the improved methods for visualization and quantitation of organ injury and the possibilities of physiological or pharmacological intervention, nuclear medicine gives the clinician potent tools for the monitoring of organ function at risk during cancer therapy. The trend to intensify cancer treatment by combining various treatment modalities and the increasing chances of prolonged survival in a large number of patients call for effective integration of nuclear medicine methods into the recommended guidelines for grading organ injury in clinical oncology.

Antineoplastic Agents↗
PubMed1993

Standardized quantitative 67Ga scintigraphy in relation to carbon monoxide diffusion capacity in pulmonary sarcoidosis.

67Ga lung uptake, obtained by a standardized computer-assisted quantitative method of 67Ga scintigraphy, was compared to carbon monoxide diffusion capacity (DLCO) in 45 patients with biopsy proven pulmonary sarcoidosis. Increased 67Ga lung uptake was found in 24 (53%) patients and DLCO was decreased in only 16 (36%) patients. An inverse relationship (r = -0.53; p < 0.001) was demonstrated between 67Ga lung uptake and DLCO. Eleven patients had an increased 67Ga lung uptake whereas the DLCO values were normal. There was no correlation between 67Ga lung uptake or DLCO and either chest radiographic stage or mode of clinical presentation. On the basis of the normal limits for 67Ga lung uptake and DLCO, 4 subgroups of patients could be identified. The use of the combined investigations may open an opportunity for an early identification of those patients who require therapy. An increased 67Ga accumulation within the lung seems to be considered as a factor indicating risk for pulmonary disability, which is supported by the follow-up of the 4 subgroups of patients.

Adult↗
PubMed1990

SPET brain imaging with 201 diethyldithiocarbamate in acute ischaemic stroke.

Thirty-five patients with acute ischaemic stroke were studied within 24 h after hospital admission with thallium 201 diethyldithiocarbamate single photon emission tomography (201Tl-DDC SPET) and X-ray computed tomography (CT). 201Tl-DDC is a non-redistributing agent that allows postponed imaging after early administration and early therapeutic intervention. In 16 patients both investigations were performed within 24 h after stroke onset. The sensitivity of SPET was 94% and of CT 81% in the first 24 h, when hypodensity and obliteration of sulci were used as CT reading criteria. When only hypodensity was used as a criterion, the sensitivity of CT was 50% in this group. Sensitivity of CT compared with SPET became increasingly better in patients with older infarcts (1-18 days). In two-thirds of patients, the lesion demonstrated on SPET was larger than that on CT, and this was especially so with older infarcts. Crossed cerebellar diaschisis occurred in 69% of patients. The high sensitivity of 201Tl-DDC SPET in the first 24 h after ischaemic stroke and the favourable properties of this radiopharmaceutical make it a method of interest in the assessment of initial perfusion defects in early experimental stroke therapies.

Aged↗
PubMed1990

European multi-centre comparison of thallium 201 and technetium 99m methoxyisobutylisonitrile in ischaemic heart disease.

Fifty-six patients in Europe were entered into a multi-centre study to compare the accuracy of technetium 99m methoxyisobutylisonitrile (99mTc-MIBI) for the detection of coronary artery disease (CAD) with thallium 201 (201Tl) chloride perfusion scanning. The results showed a high degree of concordance between the two radiopharmaceuticals. Some 81% (678/840) of myocardial segments showed the same result (normal, infarct or ischaemia), and 80% (45/56) of patients had the same diagnosis. Overall detection of CAD in patients was 98% for 201T1 and 96% for 99mTc-MIBI. Detection of CAD in total arteries was 68% for both agents. In this study 99mTc-MIBI was as accurate as 201Tl for the detection of coronary artery stenoses.

Contrast Media↗
PubMed1988

Lung volume calculations from 81Krm SPECT for the quantification of regional ventilation.

Lung volumes, calculated from 81Krm single-photon emission computed tomography (SPECT) of the lungs, were compared with functional residual capacity (FRC), measured with the helium dilution technique in controls and in patients with various pulmonary diseases. SPECT volume was greater than FRC, which was attributed to non-gas-containing structures in the lung such as the alveolar walls, the interstitium, the blood vessels and the blood, included in the SPECT volume. A good correlation (r = 0.91) was found between the two volumes and there was no difference in this relationship between patients and controls. It was concluded that the relative volume distribution, calculated from SPECT, can be used for the quantification of ventilation from 81Krm SPECT steady-state count distributions.

Adult↗
PubMed1988

New radionuclide tracers for the diagnosis and therapy of medullary thyroid carcinoma.

Medullary thyroid carcinoma (MTC), a calcitonin-producing tumor that occurs in familial and sporadic forms, can be monitored satisfactorily with measurements of calcitonin and CEA in serum. However, locating the tumor site may be difficult. In the current review of the experience with four new radionuclide tracers for MTC, the relative value of each of these procedures is outlined. Total body imaging using TI-201 chloride and Tc-99m(V) DMSA are both sensitive techniques that can be used for the detection and follow-up of MTC. Imaging using I-131 MIBG and I-131 anti-CEA antibodies/fragments should be performed once the diagnosis and the tumor site have been established, to evaluate if patients might be amenable for therapy with one of these radiopharmaceuticals.

3-Iodobenzylguanidine↗
PubMed1988

Standardized quantitative 67Ga scintigraphy in pulmonary sarcoidosis.

A method of standardized quantitative 67Ga scintigraphy in the evaluation of pulmonary sarcoidosis is described. Standardization of 67Ga activity measurements was achieved by using an external attenuated 67Ga standard for comparison. The method was applied to control subjects (n = 24), and to patients (n = 88) suffering from biopsy-proven pulmonary sarcoidosis, whether or not treated with systemic or inhaled corticosteroids. The quantitative 67Ga activity values for pulmonary hili and parenchyma were found to be increased in patients, especially in those patients who were recently diagnosed and untreated. 67Ga accumulation in the liver showed normally a wide variation and appeared to be increased in patients with sarcoidosis, so that use of the liver radioactivity as the standard for comparison may lead to misinterpretation of the intrathoracic 67Ga activity distribution. Standardized quantitative 67Ga scintigraphy appeared to be a valuable tool in the management of pulmonary sarcoidosis and also opens up the possibility for results from different institutions to be compared. Supplementary digitized functional images improved the accuracy of the interpretation of routine analogue unprocessed images. Diffuse or local 67Ga accumulation in the chest was more readily discernible on digitized functional images than on analogue images.

Female↗
PubMed1987

Cerebral blood flow imaging with thallium-201 diethyldithiocarbamate SPECT.

Thallium-201 diethyldithiocarbamate ([201TI]DDC) was studied in humans as an agent for cerebral blood flow imaging. Brain uptake proved to be complete 90 sec after injection with no appreciable washout or redistribution for hours. Intracarotid injection suggested an almost 100% extraction during the first passage. Whole-body distribution studies demonstrated a brain uptake of 4.3% of the dose compared with 0.9% for [201TI]chloride. No differences were found in the distribution of [201TI]DDC versus [201TI]chloride in other organs. After the injection of 3 mCi 201TI, good quality single photon emission computed tomographic (SPECT) images of the brain were obtained with both a rotating gamma camera and a multidetector system. In ischemic brain disease, perfusion defects were easily demonstrated. We conclude that [201TI]DDC is a suitable radiopharmaceutical for SPECT studies of cerebral blood flow.

Aged↗
PubMed1986

Gallium-67 lung scintigraphy in patients with acquired immune deficiency syndrome (AIDS).

Fifteen 67Ga lung scans were obtained from 11 men with AIDS to detect opportunistic lung infection. Results were compared with clinical findings, chest radiographs, CO-transfer and transbronchial biopsies or BAL. Clinical symptoms were least helpful in diagnosing pneumonia. Chest radiographs were normal in six of eight normal 67Ga studies and abnormal in four of seven abnormal scans. In four cases the X-ray showed equivocal abnormalities, twice corresponding to a normal and twice to an abnormal scan. Once the X-ray was normal, but the scan showed diffuse abnormalities. CO-transfer in patients with a normal scan was higher (55-68%) than in patients with an abnormal scan (22-44%). Biopsy or BAL revealed P. carinii in five of six patients. Cytomegalo-virus was isolated once. All six patients had abnormal 67Ga scans. 67Ga lung scintigraphy is a sensitive indicator of active lung disease in AIDS, especially when chest X-rays are normal or equivocal.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Thallium-201 diethyldithiocarbamate: an alternative to iodine-123 N-isopropyl-p-iodoamphetamine.

The study of cerebral blood flow by single photon emission computed tomography (SPECT) requires lipophilic radiopharmaceuticals. The high cost and limited availability of N-isopropyl-p-[I-123]-iodoamphetamine ( [123I]IMP) led us to search for alternatives. Following our recent development of thallium-201 diethyldithiocarbamate ( [201TI]DDC), we have compared the brain uptake of [123I]IMP and [201TI]DDC in rabbits. The brain bound 1.14 +/- 0.28% (s.e.m.) of the dose of the injected [123I]IMP and 1.46 +/- 0.28% of the [201TI]DDC. Brain activity of [201TI]DDC remained stable from 1.5 min after injection up to at least 1 hr. The [201TI]DDC uptake was more instantaneous than that of [123I]IMP. The ratios of gray to white matter distribution were about equal: 1.41 for [123I]IMP and 1.44 for [201TI]DDC. The lungs retained 8.32% of the dose of [123I]IMP and only 0.53% of the [201TI]DDC. In brain macroautoradiography [201TI]DDC yielded images of good quality with excellent demarcation of gray and white matter, persisting for at least 45 min after injection. We conclude that [123I]IMP and [201TI]DDC are equally suitable for blood flow study of the rabbit brain. The first human tomographic results obtained in two healthy volunteers demonstrate that clinical application of SPECT [201TI]DDC may be feasible.

Amphetamines↗
PubMed1984

Bone scintigraphy in patients with operable breast cancer stages I and II. Final conclusion after five-year follow-up.

A 5-yr follow-up study was performed in 90 patients with stage I and II breast cancer who had a routine preoperative bone scan. The percentage of positive preoperative scans was 3.4%. Twenty-four of the 90 patients died within 5 yr. In all patients except five a follow-up scan was obtained. The results of our first study were confirmed. In only one of the three patients with a positive preoperative scan suspicious for bone metastases did bone metastases develop in this 5-yr follow-up study. One patient with an equivocal preoperative scan developed bone metastases. In 14 of the 16 patients with bone metastases and a positive scan in the follow-up period the preoperative scan was negative. From the preoperative and follow-up scan results we conclude that in stage I and II breast cancer there is no value in preoperative bone scanning. Routine bone scanning in the follow-up period appears to have little value in the asymptomatic patient.

Bone Neoplasms↗
PubMed1983

A method of quantitative 67Ga scintigraphy in the evaluation of pulmonary sarcoidosis.

67Ga scintigraphy was performed in 42 patients with pulmonary sarcoidosis and in 30 control subjects. Accumulation of the radionuclide in hili and lungs was quantified by a computer method. The values in control subjects were found to be within a relatively narrow range. The pattern of 67Ga accumulation clearly differed in patients who were radiographically defined as having only lymphadenopathy and in patients also having parenchymal involvement. Corticosteroid therapy resulted in a sharp decline of values of isotope uptake, although hilar activity remained slightly elevated. The quantitative uptake measurement proved to be superior to a subjective scoring method.

Adrenal Cortex Hormones↗
PubMed1983

67Ga scintigraphy, serum lysozyme and angiotensin-converting enzyme in pulmonary sarcoidosis.

67Ga scintigraphy, using a 67Ga accumulation score, was compared with serum lysozyme (LZM) and angiotensin-converting enzyme (ACE) levels in 34 patients with biopsy-proven, pulmonary sarcoidosis. Serum LZM and ACE values varied between 1.0 to 21.3 mg/l (mean 4.3 +/- 3.4 mg/l) and 33 to 146 U/l (mean 69 +/- 26 U/l), respectively. Normal values were found in 26 and 35% of the patients. All patients, however, had abnormal 67Ga uptake in the pulmonary hilar lymph nodes and/or parenchyma. The follow-up of untreated and treated patients supports the suggestion that 67Ga scintigraphy is more useful for assessing the extent and activity of the intrathoracic sarcoid lesions. Serum LZM and ACE measurements are helpful, but normal LZM and ACE values do not exclude activity and progression of disease in pulmonary sarcoidosis.

Adult↗
PubMed1983

Diagnosis of upper-abdominal infections by In-111 labeled leukocytes with Tc-99m colloid subtraction technique.

In 65 patients suspected of upper-abdominal inflammatory disease, indium-111 leukocyte scintigraphy was combined with a Tc-99m(Sn)colloid scan by computer-assisted subtraction. In 84% of these cases, a definite diagnosis would not have been possible without this method of subtraction. Accuracy was found to be 80%, sensitivity 93%, and specificity 59%. False-positive results were due either to noninfectious inflammatory lesions with accumulation of leukocytes or to some pitfalls in the subtraction technique itself.

Abdomen↗
PubMed1981

111Indium-labelled leucocyte scintigraphy in the diagnosis of inflammatory disease--first results.

In 61 patients, 66 scans were performed with 111In-labelled autologous leucocytes to evaluate this method in the diagnosis of inflammatory disease. All scintigraphic results were compared with clinical, operative or postmortem findings. In the first 20 examinations in 19 patients, 2 scintigrams were true positive, 9 true negative one of false positive, whereas 9 scintigrams had to be considered as false negative. These false negative results were probably due to loss of viability of the labelled cells. A modified labelling technique, in which a much lower concentration of oxine was used, was employed for a further 46 examinations in 42 patients. Twenty-four scintigrams were true positive and 22 true negative, while no false positive or false negative results were observed. These results suggest that this modified technique is useful in the diagnosis of inflammatory disease.

Abdomen↗
PubMed1981

Bone scintigraphy and densitometry in symptomatic haemodialysis bone disease.

Bone scintigraphy and densitometry (iodine-125 photon absorptiometry) were performed in eight patients with symptomatic haemodialysis bone disease. The bone scintiscan showed either hot spots or hyperactivity as a feature of metabolic bone disease. The bone density (BMC/W) was reduced, but could not be distinguished from the degree of demineralisation found in asymptomatic patients on long-term haemodialysis. Therefore, bone density measurements require critical interpretation. Complementary bone scintigraphy should be used in symptomatic haemodialysis bone disease for assessing the extent of the disease.

Adult↗