99mTc-MIBI SPECT in primary hyperparathyroidism. Influence of concomitant vitamin D deficiency for visualization of parathyroid adenomas.

UNLABELLED: AIM of the study was to analyse the influence of a concomitant vitamin D deficiency on the results of (99m)Tc-MIBI studies in patients (pts) with primary hyperparathyroidism (pHPT). PATIENTS, METHODS: Between January 1998 and May 2004, 71 pts with pHPT had undergone operation after a (99m)Tc-MIBI study of whom 54 pts (76%) had normal values of 25-OH-vitamin D3 and 17 pts (24%) had vitamin D deficiency. Results of a dual-phase (99m)Tc-MIBI protocol with SPECT were compared with histopathology. RESULTS: In 54 pts with normal vitamin D values late SPECT images identified more lesions (n=51, sensitivity 91%) than early planar (n=45, sensitivity 82%) or late planar images (n=50, sensitivity 88%). In 17 pts with vitamin D deficiency late SPECT images identified more lesions (n=13, sensitivity 72%) than early planar (n=10, sensitivity 56%) or late planar images (n=10, sensitivity 56%) too. In pts with vitamin D deficiency the sensitivity of a (99m)Tc-MIBI SPECT study was lower than in those with normal vitamin D status (72% vs. 91%) and dependent on the value for PTH. However, the results did not reach statistical significance: early planar: p=0.1625; late planar: p=0.0039; (99m)Tc-MIBI SPECT: p=0.1180. CONCLUSION: The likelihood of a pathological (99m)Tc-MIBI study being obtained in pts with pHPT is dependent on the parathyroid hormone level. However, a negative influence of a low vitamin D level on the scintigraphic detection rate of a parathyroid adenoma could not be proven which may be due to the low number of pts with vitamin D deficiency.

Administration of additional inactive iodide during radioiodine therapy for Graves' disease: who might benefit?

AIM: Graves' hyperthyroidism and antithyroid drugs empty the intrathyroid stores of hormones and iodine. The consequence is rapid 131I turnover and impending failure of radioiodine therapy. Can administration of additional inactive iodide improve 131I kinetics? PATIENTS, METHODS: Fifteen consecutive patients, in whom the 48 h post-therapeutically calculated thyroid dose was between 150 and 249 Gy due to an unexpectedly short half-life, received 3 x 200 microg inactive potassium-iodide (127I) daily for 3 days (Group A), while 17 consecutive patients with a thyroid dose of > or = 250 Gy (Group B) served as the non-iodide group. 48 hours after 131I administration (M1) and 4 or 5 days later (M2) the following parameters were compared: effective 131I half-life, thyroid dose, total T3, total T4, 131I-activity in the T3- and T4-RIAs. RESULTS: In Group A, the effective 131I half-life M1 before iodine (3.81 +/- 0.93 days) was significantly (p < 0.01) shorter than the effective 131I half-life M2 (4.65 +/- 0.79 days). Effective 131I half-life M1 correlated with the benefit from inactive 127I (r = -0.79): Administration of 127I was beneficial in patients with an effective 131I half-life M1 of <3 or 4 days. Patients from Group A with high initial specific 131I activity of T3 and T4 showed lower specific 131I activity after addition of inactive iodine compared with patients from the same group with a lower initial specific 131I activity of T3 and T4 and compared with the patient group B who was given no additional inactive iodide. This correlation was mathematically described and reflected in the flatter gradient in Group A (y = 0.5195x + 0.8727 for 131I T3 and y = 1.0827x - 0.4444 for 131I T4) and steeper gradient for Group B (y = 0.6998x + 0.5417 for 131I T3 and y = 1.3191x - 0.2901 for 131I T4). Radioiodine therapy was successful in all 15 patients from Group A. CONCLUSION: The administration of 600 microg inactive iodide for three days during radioiodine therapy in patients with Graves' hyperthyroidism and an unexpectedly short half-life of <3 or 4 days was a safe and effective alternative to the administration of a second radioiodine capsule.

Radioiodine therapy of Graves' hyperthyroidism in patients without pre-existing ophthalmopathy: can glucocorticoids prevent the development of new ophthalmopathy?

BACKGROUND: Radioiodine therapy (RIT) combined with glucocorticoids is an effective therapy for Graves' disease, but it is debatable whether glucocorticoids should be applied in patients without Graves' ophthalmopathy (GO). METHODS: The effect of 0.4 - 0.5 mg prednisone every second day over a period of 5 weeks after RIT was monitored over a follow-up period of at least 12 months after RIT. A questionnaire was sent to 186 consecutive patients without GO concerning eye symptoms after RIT. 148 patients (80 %) answered. If eye symptoms had occurred after RIT, additional clinical examination was carried out at our outpatient clinic. The primary endpoint was the absence or onset of GO within the first year after RIT. RESULTS: Within 12 months after RIT the examination confirmed GO in 5 out of 148 patients (3.4 %). In all cases the symptoms were transient. No adverse reaction to the use of prednisone after RIT was noted. CONCLUSIONS: The risk of new GO in the first year after RIT was low and the clinical course of GO was mild when RIT was combined with a low-dose glucocorticoid regimen. Preventive administration of glucocorticoids can therefore be recommended in patients with Graves' disease even without evident GO.

Improvement of myocardial blood flow to ischemic regions by angiotensin-converting enzyme inhibition with quinaprilat IV: a study using [15O] water dobutamine stress positron emission tomography.

OBJECTIVES: This study was designed to analyze the effects of acute angiotensin-converting enzyme (ACE) inhibition on myocardial blood flow (MBF) in control and ischemic regions. BACKGROUND: Although animal studies indicate an improvement of MBF to ischemic regions after ACE inhibition, this effect has not been conclusively demonstrated in patients with coronary artery disease. METHODS: Myocardial blood flow was analyzed in ischemic and nonischemic regions of 10 symptomatic patients with coronary artery disease using repetitive [15O] water positron emission tomography at rest and during maximal dobutamine stress before and after ACE inhibition with quinaprilat 10 mg i.v. To exclude the possibility that repetitive ischemia may cause an increase in MBF, eight patients underwent the same protocol without quinaprilat (placebo patients). RESULTS: Rate pressure product in control and quinaprilat patients was comparable. In placebo patients, repetitive dobutamine stress did not change MBF to ischemic regions (1.41 +/- 0.17 during the first stress vs. 1.39 +/- 0.19 ml/min/g during the second stress, p = 0.93). In contrast, MBF in ischemic regions increased significantly after acute ACE inhibition with quinaprilat during repetitive dobutamine stress (1.10 +/- 0.13 vs. 1.69 +/- 0.17 ml/min/g, p < 0.015). Dobutamine coronary reserve in ischemic regions remained unchanged in placebo patients (1.07 +/- 0.11 vs. 1.10 +/- 0.16, p = 0.92), but increased significantly after quinaprilat (0.97 +/- 0.10 vs. 1.44 +/- 0.14, p < 0.002). Total coronary resistance decreased after ACE inhibition (123 +/- 19 vs. 71 +/- 10 mm Hg x min x g/ml, p < 0.02). CONCLUSIONS: Angiotensin-converting enzyme inhibition by quinaprilat significantly improves MBF to ischemic regions in patients with coronary artery disease.

Technetium 99m-MIBI-SPECT: A highly sensitive diagnostic tool for localization of parathyroid adenomas.

BACKGROUND: The aim of this study was to assess the value of technetium 99m-MIBI scintigraphy using the single photon emission computed tomography (SPECT) technique for preoperative localization of smaller (

Long-term follow-up of 82 patients with chronic disease of the thoracic aorta using spin-echo and cine gradient magnetic resonance imaging.

The objective of this study to examine the clinical impact of magnetic resonance imaging in long-term follow-up of patients (pts) with chronic disease of the thoracic aorta such as coarctation of the aorta, chronic aortic dissection and true aortic aneurysm. A total of 322 magnetic resonance examinations obtained in 82 pts with chronic disease of the thoracic aorta (31 pts with coarctation of the aorta (CoA), 29 pts with chronic aortic dissection and 22 pts with true aneurysm) over a period of 0.25 to 13.5 (mean +/- SD: 6.5 +/- 3.4) years were retrospectively reviewed. Diameters of the thoracic aorta were measured at predefined levels and morphological and functional parameters of special interest were analysed in each patient group. Pts were classified as having constant or progressive disease and clinical end-points were defined as (re-)operation or death. 43 pts (52%) (CoA 15 pts, chronic dissection 16 pts, true aneurysm 12 pts) had constant findings. None of them underwent (re-)operation and seven patients (16%) died, three of them from their aortic disease more than five years later after their last magnetic resonance examination, one from an arrhythmogenic event, and in the remaining 3 pts the cause of death could not be definitely established. 39 pts (48%) (CoA 16 pts, chronic dissection 13 pts, true aneurysm 10 pts) had progressive disease as demonstrated by repetitive magnetic resonance imaging. Of these 39 pts 24 pts underwent (re-)operation, in 15 pts operation was postponed. Four pts died from their aortic disease. Repetitive magnetic resonance imaging is a clinically feasible technique for long-term follow-up of pts with chronic disease of the thoracic aorta because it can detect progressive disease in a large subset of pts requiring elective surgery. The results of magnetic resonance imaging provided the rationale for either (re-)operation or conservative management, thus guiding patient management.

[Effect of antithyroid medication on the effective half-life and uptake of 131-iodine following radioiodine therapy]. / Einfluss von thyreostatischer Medikation auf die effektive Halbwertszeit und den Uptake von 131Iod während einer Radioiodtherapie.

AIM: A radioiodine therapy (RIT) in thyrotoxic patients receiving antithyroid drugs (ATD) leads in comparison to nonpretreated patients either to higher therapeutic doses or to higher treatment failure rates. Aim of this study was to optimize the effect of RIT in patients pretreated with ATD. METHODS: Therefore, the influence of ATD was assessed in 109 patients with shortened effective half-life of 131I. RIT was performed under stationary conditions. Radioiodine activity of the thyroid gland was measured twice a day. In 77 patients antithyroid medication was stopped three days after RIT. The progress of the first RIT and of a second radioiodine application, which still was necessary in 29 patients, was compared to 32 patients receiving ATD, continuously. RESULTS: Values of effective half-life for 131I rose significantly from 3.2 +/- 0.2 to 5.7 +/- 0.2 days (Graves' disease: 3.4 to 5.7 days; toxic goiters' disease: multifocal autonomy 3.2 to 6.2 days; unifocal autonomy 2.5 auf 5.0 days) 2-3 days after stopping ATD. There was an increase of the 131I-uptake of a second after stopping ATD, too. In contrast, 131I-uptake of a second RIT decreased significantly in patients receiving ATD, continuously. CONCLUSION: Effective half-life and uptake of 131I was affected significantly by ATD. The stop taking of ATD after RIT is useful to improve an apparent insufficient RIT in thyrotoxic patients receiving ATD.

[Radioiodine therapy of Graves' disease--a dosimetric comparison of various therapy regimens of antithyroid agents]. / Radiotherapie des Morbus Basedow--dosimetrischer Vergleich verschidener Therapieregime bezüglich der Thyreostatikagbe.

AIM: Premedication with antithyroid drugs (ATD) compared to patients not pretreated with ATD causes a higher failure rate of radioiodine therapy (RITh) or demands higher therapeutical dosage of radioiodine (RI). For clinical reasons and because of accelerated iodine metabolism in hyperthyreosis a compensated thyroid metabolism is desirable. Aim of this study was to investigate the influence of ATD on the biokinetics of RI in case of Graves' disease in order to improve RITh of patients pre-treated with ATD. METHODS: 385 consecutive patients who underwent RITh because of Graves' disease for the first time were included: Group A (n = 74): RITh under continuous medication with ATD; Group B (n = 111): Application of RI under continuous medication with ATD, in case of insufficient RI-uptake or shortened effective RI-half-life ATD were stopped 1-5 days after RITh; Group C (n = 200): ATD were stopped 2 days prior to RITh in all patients. We examined the influence of ATD on RI-uptake and effective RI-half-life as well as the absorbed dose achieved on the thyroid in dependence of thyroid volume and applied RI-dosage [TEQ--therapy efficiency quotient, (2)]. RESULTS: In the RI-pretest (all patients under ATD) the RI-uptake was comparable in all three groups. During RITh RI-uptake, effective RI-half-life and therefore the TEQ were significantly higher in Group C as compared to Groups A and B (p < 0.001, respectively). In Group B the medication with ATD was stopped in 61 of 111 cases 1-5 days after RITh. In this subgroup the effective RI-half-life increased from 4.4 +/- 1.7 d to 5.1 +/- 1.6 d after stopping of ATD (p = 0.001). CONCLUSION: Stopping of ATD 2 days prior to RITh leads to an increased efficiency of about 50% compared to RITh carried out under ATD and therefore to a clear reduction of radiation exposure to the rest of the body with equal absorbed doses of the thyroid. Stopping of ATD shortly after RITh increases efficiency in case of short effective RI-half-life, but it is inferior to stopping ATD 2 days prior to RITh.

[The effect of hyper- and hypothyroidism on the energy metabolism of skeletal muscles--a study using 31P-magnetic resonance spectroscopy]. / Einfluss von Hyper- und Hypothyreose auf den Energiestoffwechsel der Skelettmuskulatur--Eine Untersuchung mit 31P-Kernspinspektroskopie.

31P magnetic resonance spectroscopy allows non-invasive evaluation of phosphorus metabolism in man. The purpose of the present study was to assess the influence of hyper- and hypothyroidism on the metabolism of resting human skeletal muscle. The present data show that quantitative measurement of phosphate metabolism by NMR is possible as also demonstrated by other studies. Using a quantitative evaluation method with an external standard, significant differences in the levels of phosphocreatine, adenosine triphosphate, and phosphodiesters were found. In hypothyroid patients a TSH-dependent increase in phosphodiesters and a decrease in adenosine triphosphate and phosphocreatine was observed. In hyperthyroidism a similar decrease in adenosine triphosphate but a considerably higher decrease in phosphocreatine occurred. In the light of the results of other studies of muscle metabolism, these changes appear to be non-specific so that further studies are required to assess the clinical value of such measurements.

[Prevention, screening and therapy of thyroid diseases and their cost-effectiveness]. / Prävention, Screening und Therapie gutartiger Schilddrüsenerkrankungen unter dem Aspekt von Kosten und Nutzen.

Cost-effectiveness analyses focused on benign thyroid diseases are under-represented in the literature. The calculation of costs per additionally gained life year is difficult: The benefit of prevention is shifted into the distant future. The influence of an untreated subclinical thyroid disease on life expectancy can only be demonstrated by a long-term follow-up and by epidemiological databases. Iodine supplementation and programs for the prevention of tobacco smoking (primary prevention) are very cost-effective. Smoking increases the risk both of multinodular goiter and of Graves' disease. Screening programs (secondary prevention) are discussed for the laboratory parameters thyrotropin (TSH), calcium and calcitonin. TSH testing seems to be very cost-effective for epidemiological considerations in a certain lifespan (newborn, pregnancy, postpartal, older persons, hospitalisation due to acute diseases) and in persons with previously elevated TPO-antibodies or TSH-values >2 mU/l, but dedicated cost-effectiveness analyses are lacking. On the other hand, the cost-effectiveness of a routine TSH testing beyond the age of 35 years has been shown by a high-quality decision analysis. Therapeutic strategies (tertiary prevention) aim at the avoidance of complications (atrial fibrillation, myocardial infarction, death for cardiac reasons) and of iatrogenic complications. Examples of a tertiary prevention are: firstly the definitive therapy of Graves' disease in patients who have an increased risk of relapse after antithyroid drugs (ATD), secondly the radioiodine therapy for subclinical hyperthyroidism and the radioiodine therapy of large goiters in older patients or in patients suffering from a relevant comorbidity. Cost-effectiveness analyses for different therapeutic strategies of Graves' disease were published using a lifelong time-horizon. The ablative radioiodine dose-regime is cost-effective as a first line therapy if the risk of relapse after ATD exceeds 60%.

[Cost-effectiveness of PET in the management algorithms of lung tumors: comparison of health economic data]. / Kosteneffektivität der PET im Behandlungsalgorithmus der Lungentumoren: Ein Vergleich gesundheitsökonomischer Daten.

Modelling is an accepted, valid and often necessary method for assessing economic effectiveness in terms of cost per life year gained. Comparing an alternative strategy (a) with a baseline strategy (bl), the incremental cost (COSTa-COSTbl) divided by the incremental life expectancy (LEa-LEbl) defines the incremental cost-effectiveness ratio (ICER). Taking watchful waiting as the low-cost baseline strategy for the management of solitary pulmonary nodules, the ICER of positron emission tomography (PET) [3218 euros (EUR) per life year saved (LYS)] was more favourable than that of exploratory surgery (4210 EUR/LYS) or that of transthoracic needle biopsy (6120 EUR/LYS). Changing the baseline strategy to exploratory surgery, the use of PET led to cost savings and additional life expectancy in case of an intermediate pretest probability of malignancy. For management of potentially operable non-small cell lung cancer the use of PET in patients with normalisized mediastinal lymph nodes on CT was most cost-effective (143 EUR/LYS), and the costs of PET were almost balanced by a better selection of patients for beneficial cancer resection. Using PET in patients with enlarged lymph nodes on CT, the ICER raised to 36,667 EUR/LYS. When PET or CT were positive for mediastinal lymph nodes, the exclusion from biopsy confirmation led to cost savings that did not justify the expected reduction in life expectancy. Economic data from the USA and Japan also demonstrated the cost-effectiveness of PET-based algorithms for the management of lung tumours.

[99m-Tc-MIBI SPECT parathyroid gland scintigraphy for the preoperative localization of small parathyroid gland adenomas]. / 99mTc-MIBI-SPECT-Nebenschilddrüsenszintigraphie zur präoperativen Lokalisation kleiner Nebenschilddrüsenadenome.

AIM: It was the of this study to assess the value of the 99mTc-MIBI scintigraphy in SPECT technique in the preoperative lateral location of small parathyroid adenoma (PTA). METHODS: 25 consecutive patients (8 male, 17 female, mean age 63 +/- 13 years) with the established diagnosis of primary hyperparathyroidism and non-diagnostic ultrasonography were scanned preoperatively. After a thyroid examination to exclude radionuclide accumulating thyroid adenoma, planar and tomographic images were acquired 20 min. and 120 min. after i.v. injection of 740 MBq 99mTc-MIBI using a 3 head gamma camera (Picker Prism 3000). The first 10 patients underwent an additional 201Tl/99mTc subtraction scintigraphy in a 2 days protocol. RESULTS: All patients had small, solitary PTA (< 1 g). 201Tl/99mTc subtraction scintigraphy (n = 10) showed only a sensitivity of 50%. Using planar MIBI-scintigraphy lateral location of PTA was possible in 18 cases (sensitivity: 72%). There was an increase in sensitivity up to 96% using the SPECT technique and the 3D display (volume-rendered reprojection). CONCLUSION: In contrast to 201Tl/99mTc subtraction scintigraphy, which showed only a low sensitivity, a reliable lateral location of small PTA was obtained using the tomographic 99mTc-MIBI scintigraphy. This method offers e.g. the possibility for the surgeon to perform an unilateral parathyroidectomy.

[Effect of iodine application during radioiodine therapy in patients with impending therapy failure]. / Einfluss einer lodidgabe während der Radioiodtherapie bei Patienten mit drohendem Therapieversagen.

AIM: We investigated whether additional application of "cold" iodine after therapy with radioiodine could result in a prolongation of the effective half life of iodine-131 and would thus lead to an increase of the effective thyroid radiation dose. METHODS: Time-activity-curves after therapy with radioiodine were analysed in 25 patients (16 women, 9 men). Nine patients suffered from autonomously functioning thyroid nodules, 5 from autonomous multinodular goiter and 11 from Graves' disease. These patients had an effective half life shorter than 4 days resulting in an undertreatment of > 20% with respect to the desired effective thyroid radiation dose. 2-4 days after therapy with radioiodine all patients received "cold" iodine for three days in a dose of 3 x 200 micrograms per day. RESULTS: In 14 of the 25 patients an increase of the effective half life was observed. Patients with an autonomously functioning thyroid nodule showed a mean increase of the effective thyroid radiation dose of 40 +/- 44 Gy, patients with toxic multinodular goiter of 29 +/- 30 Gy and patients with Graves' disease of 37 +/- 37 Gy. CONCLUSION: Additional application of "cold" iodine after therapy with radioiodine can prolong the effective half life in selected patients. We suspect a correlation with the thyroid iodine pool. This will be the basis for further investigations hopefully resulting in a better patient preselection to determine who might respond to this therapy.

[31P-magnetic resonance spectroscopy: impaired energy metabolism in latent hyperthyroidism]. / 31Phosphor-Kernspinspektroskopie: Gestörter Energiestoffwechsel bei latenter Hyperthyreose.

31Phosphorus magnetic resonance spectroscopy allows an in vivo examination of energy metabolism. The present study was designed to evaluate whether in patients with latent hyperthyroidism alterations of muscle energy metabolism could be found similar to those observed in patients with overt hyperthyroidism. In 10 patients with overt hyperthyroidism before therapy and 20 with latent hyperthyroidism (also without therapy) and in 24 healthy volunteers magnetic resonance spectroscopy of the calf muscle was performed within a 1.5-Tesla magnet. Muscle concentrations of phosphocreatine, inorganic phosphate, and ATP were quantified compared to an external standard solution of K2HPO4. In the patients with overt hyperthyroidism and with latent hyperthyroidism a significant decrease of phosphocreatine was found. Further, the ATP concentration in patients with latent and manifest hyperthyroidism tended towards lower values. There were no significant differences in the decrease of phosphocreatine and ATP between both patient groups. Therefore, this study for the first time shows that alterations of energy metabolism in latent hyperthyroidism can be measured and that they are similar to those observed in overt hyperthyroidism.

[Consequences of new patient discharge guidelines on the cost structure of radioiodine therapy]. / Auswirkungen der neuen Entlassungsrichtwerte auf die Kostenstruktur der Radioiodtherapie.

AIM: Consequences of the new recommendations by the Federal German Radiation Protection Committee (SSK) for patient discharge guidelines (residual activity of 250 MBq for I-131) were calculated for duration of stay and radioiodine therapy cost management. METHODS: For 601 consecutively admitted patients with hyperthyreosis, actual duration of stay and duration of stay according to previous guidelines (from 1993) were calculated, as well as duration of stay according to recommended values. Following BPflV statutes, cost-analysis considered the cause and volume of goitre, and by using sensitivity analyses included a range of diagnostics, service assessment, and duration of stay. RESULTS: Duration of stay following I-131 therapy (in Germany) is expected to fall by 35-50% (average future stay 4.0 +/- 2.8 days), average costs from DM 4,452 to DM 3,680 (-17.4%). Not including pretreatment diagnostics, cost reduction (service assessment 17-24%) was estimated at 21-25%. Compared to strumectomy, I-131 therapy costs are expected to be lower for goitres (Graves' disease) up to at least 60 ml, toxic nodules of at least 25 ml, and toxic multinodular goitres of at least 90 ml. CONCLUSION: In the future, I-131 therapy will be more cost-effective even with larger goitres. Since reimbursement is determined by the duration of stay, new reimbursement procedures are discussed in this paper.

[Cost-effectiveness analysis: radioiodine or antithyroid medication in primary treatment of immune hyperthyroidism]. / Kosten-Effektivitäts-Analyse: Radioiod oder thyreostatische Medikation bei der Primärbehandlung der Immunhyperthyreose.

AIM: As first-line therapy of hyperthyroidism caused by Graves' disease antithyroid drugs are favoured in Europe, while radioiodine therapy is favoured in the USA. Radioiodine therapy has become more economic in Germany since the new recommendations by the Federal German Radiation Protection Committee (SSK) for patient discharge guidelines. METHOD: Sensitivity analyses took into account the long-term relapse rate of conservative or radioiodine therapy, use of diagnostic tests, level of health insurance, drops in productivity and a discount factor. Costing models included the costs of follow-up care over 30 years. The costs of the hospitalisation for radioiodine therapy were calculated for 300 patients, discharged with 250 MBq 1-131 residual activity. RESULT: Antithyroid drugs were considered cost-effective when they achieved relapse rate of 50% or less, a cut in the number of tests needed and reduced working hours. Failure to meet any one of these conditions makes primary radioiodine therapy more cost-effective in 1593 of 1944 calculated costing models. Repeated conservative therapies will increase clearly the overall costs. CONCLUSION: Radioiodine is a cost-effective, first-line therapy in patients with a special risk of relapse after primary conservative therapy (goitre, younger patient, persistent elevated TSH-receptor-antibodies or Tc-uptake).

[Cost minimization analysis for the definitive therapy of hyperthyroidism: comparison of goiter resection with radioiodine therapy]. / Kostenminimierungsstudie zur definitiven Therapie der Hyperthyreose: Vergleich zwischen Strumaresektion und Radiojodtherapie.

AIM: Cost-analysis of strumaresection and radioiodine treatment in patients with hyperthyreosis. METHOD: Matched by age, sex, comorbidity, volume of goiter, and entity of hyperthyreosis 18 patients of a clinic of surgery, and 28 patients of a clinic of nuclear medicine were analysed by the reimbursed costs, and by a retrospective calculation of the real costs. RESULTS: Based on the rate for the reimbursed costs the radioiodine treatment (6450 DM) was more favourably than the strumaresection (7562 DM); based on the calculation of the real costs including regional specialities there was a minimal difference in favour of the strumaresection (5185 DM versus 5562 DM) because of the selection of large goiters (median 53 ml), the longer hospitalisation after radioiodine treatment due to legal reasons (12.5 days), and the frequent controls before and after the radioiodine treatment. Most important cost-factor of the radioiodine treatment was the volume of goiter, most important cost-factor of the strumaresection was the age of the patient. The treatment of Graves disease was more expensive than that of autonomy in surgery as well as in nuclear medicine. CONCLUSION: In order to achieve cost-minimization, radioiodine treatment should be prefered in cases of small goiters or in older patients.

Biochemical classification of kidney carcinoma biopsy samples using magic-angle-spinning 1H nuclear magnetic resonance spectroscopy.

High resolution 1H nuclear magnetic resonance (NMR) spectra using spinning at the magic angle (1H MAS NMR) have been obtained on intact normal and pathological kidney tissue samples from patients undergoing surgery for renal cell carcinoma (RCC). The spectra were measured on ca. 80 mg samples and provided high resolution 1H NMR spectra in which effects of dipolar couplings, chemical shift anisotropy and magnetic susceptibility differences are minimised thus yielding high spectral resolution. Conventional one-dimensional and spin-echo spectra and two-dimensional J-resolved, TOCSY and 1H-13C HMQC spectra were also measured on selected samples and these allowed the assignment of resonances of endogenous substances comprising both cytosolic and membrane components. The tumour tissues were characterised principally by an increased lipid content. These are the first reported results on human tumour tissues using this technique and the approach offers potential for the rapid classification of different types of tumour tissue.

Follow-up of differentiated thyroid cancer: comparison of multiple diagnostic tests.

The radioablation of thyroid remnants improves the prognosis of differentiated thyroid cancer. In our prospective study an activity of 3.7 GBq 131I failed to completely ablate the remnants in 46 out of 101 patients, but a 3-year follow-up period was uneventful. One other patient had a recurrence early after thyroidectomy. In view of possible stunning effects of 131I it might be advantageous to visualize such remnants by imaging modalities which do not emit beta-particles. Our data have revealed that neither magnetic resonance imaging (MRI), nor ultrasonography (US), nor 99Tcm-sestamibi scintigraphy, nor positron emission tomography could detect or reliably exclude minimal remnants. Such remnants did not produce thyroglobulin (Tg). A 123I and 131I uptake of> 10% after thyroidectomy was associated with about a 90% probability of persistent remnants. On the other hand, MRI was helpful in the patient group (n = 32) with Tg>4ng x ml(-1) at the second whole-body scintigraphy (TSH>30 mU x l(-1)) for planning the management of lymph node metastases (n = 15 patients): 12 patients had subsequent surgery and three patients radioiodine therapy. We recommend that MRI be used early in follow-up care when Tg is elevated. The decision of whether or not to treat persistent thyroid remnants should not be made on the basis of MRI, US or nonspecific scintigraphic methods. Complete ablation did not appear to have any clinical benefit in our study group.

In Vitro and In Vivo (1)H-MR Spectroscopic Examination of the Renal Cell Carcinoma.

BACKGROUND: Paraneoplastic effects are some of the major side effects of advanced renal cell carcinoma (RCC). Magnetic resonance spectroscopy (MRS) is known as a powerful tool to study cancer cell metabolism and cancer cell - host interactions. Aim of this study was to assess tumor cell metabolism and systemic effects using (1)H-MRS. METHODS: Spectroscopic analysis of 10 patients with RCC was compared with those of 15 healthy volunteers. Local tumor metabolism was assessed using image-guided (1)H-in-vivo-spectroscopy in a 1.5 Tesla MR whole body tomograph. Systemic effects of RCC were measured using (1)H-High-Resolution (HR) spectra of blood plasma samples in a 500 MHz Bruker DRX 500 spectrometer. RESULTS: In-vivo-spectroscopy can significantly differentiate tumor tissue from healthy renal tissue by comparing their lipid composition. Moreover after detailed assignment of the various metabolites in blood plasma in the in-vitro-HR-spectra significant systemic alterations could be identified in patients with RCC especially regarding lipid and amino acid metabolism. CONCLUSION: This work indicates that using (1)H-MRS both changes in tumor metabolism and resulting systemic/paraneoplastic effects can be assessed in patients with RCC. This approach therefore offers scope for diagnosis and therapy evaluation.