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Graves' disease (GD) is characterized by circulating TSH receptor antibodies (TRAb), and so-called hyperthyroid autoimmune thyroiditis (H-AIT) generally shows negative TRAb results with first-generation assays. However, a positive titer was observed in up to 13% of patients with euthyroid or hypothyroid autoimmune thyroiditis (AIT) by second-generation TRAb assays, and a larger increase is expected in hyperfunctioning forms. A thyroid 99mTc-pertechnetate uptake (TcTUs) cutoff of 2% previously was shown to accurately discriminate between GD and H-AIT. Here we evaluated the relationship between second-generation TRAb assays and TcTUs in 139 patients with untreated autoimmune hyperthyroidism. An increase in TRAb levels was found in 114 of 139 patients (82%). All patients with TcTUs >2% and 66% of those with lower values had positive TRAb measurements. When the cutoff was increased to 5.9 U/l, positive TRAb occurred in 92.6% of those having higher TcTUs and in 1.4% of those with lower TcTUs. TRAb levels significantly increased in patients with TcTUs higher than 2% as compared with those having lower values, while no differences occurred in patients with TcTUs ranging from 0 to 1%, from 1.1 to 1.5%, or from 1.6 to 2%. A significant relationship between TRAb and TcTUs (as well as fT3, fT4, and thyroid volume) was found. TcTUs, fT4, fT3, and thyroid volume significantly increased in patients with positive TRAb (cutoff 1.5 U/l) compared with those testing negative. Our data indicate that a large proportion of patients with hyperthyroidism and hypoechoic thyroid, including those previously diagnosed as having H-AIT, actually have circulating TRAb. TRAb levels predicate the degree of iodine uptake (as measured by TcTUs) and thyroid hyperfunction. The role of baseline TRAb measurement by second-generation assays to predict patients' outcome needs to be further evaluated and compared with TcTUs in prospective studies.

Unlabelled: Aim of this study is the validation of a simple method for evaluating the depth of the target volume within the radioiodine test by analyzing the emitted iodine-131 energy spectrum., Patients, Methods: In a total of 250 patients (102 with a solitary autonomous nodule, 66 with multifocal autonomy, 29 with disseminated autonomy, 46 with Graves' disease, 6 for reducing goiter volume and 1 with only partly resectable papillary thyroid carcinoma), simultaneous uptake measurements in the Compton scatter (210 +/- 110 keV) and photopeak (364-45/+55 keV) windows were performed over one minute 24 hours after application of the 3 MBq test dose, with subsequent calculation of the respective count ratios. Measurements with a water-filled plastic neck phantom were carried out to perceive the relationship between these quotients and the average source depth and to get a calibration curve for calculating the depth of the target volume in the 250 patients for comparison with the sonographic reference data. Another calibration curve was obtained by evaluating the results of 125 randomly selected patient measurements to calculate the source depth in the other half of the group., Results: The phantom measurements revealed a highly significant correlation (r = 0,99) between the count ratios and the source depth. Using these calibration data, a good relationship (r = 0,81, average deviation 6 mm corresponding to 22%) between the spectrometric and the sonographic depths was obtained. When using the calibration curve resulting from the 125 patient measurements, the overage deviation in the other half of the group was only 3 mm (12%). There was no difference between the disease groups., Conclusion: The described method allows on easy to use depth correction of the uptake measurements providing good results.

Aim: The TCTUs (global (99m)Tc-pertechnetate thyroid uptake under suppression) can be used as an estimate of the iodine clearance of non-TSH regulated tissue. High TCTUs levels are characteristic for Graves' disease (GD). Decreased uptake has been described in autoimmune thyroiditis (AIT). However, systematically investigated data in a larger series of AIT-patients with subclinical or overt hyperthyroidism are not published so far. The purpose of this study is the evaluation of the TCTUs in the differentiation between AIT and GD in patients with hyperthyroidism., Methods: We determined the TCTUs in 59 patients with untreated hyperthyroid GD and in 51 patients with AIT who had subclinical or manifest hyperthyroidism without medication. Patients with GD were characterized by the presence of hyperthyroidism, decreased echogenicity of the thyroid, elevation of TSH-receptor autoantibodies (TRAb). AIT was defined by a decreased echogenicity of the thyroid, absence of elevated TSH-receptor autoantibodies (TRAb), autoantibodies against the thyroid peroxidase (anti-TPO) and spontaneous remission or development of subclinical hypothyroidism within 3 months., Results: Thyroid volumes of patients with AIT were significantly lower than those of patients with GD (p <0.05). TRAb levels were significantly higher in GD-patients (median: 19.5 U/ml; range: 15.3-35 U/ml) than in AIT-patients (median: 1.3 U/ml; range: 0-4.1 U/ml). 73% (38/59) of patients with GD had elevated anti-TPO levels. In these patients anti-TPO levels (median: 768 U/l; range: 83-6397 U/l) were not significantly different from anti-TPO levels of patients with AIT (median: 834 U/l; range: 107-8675 U/l; p = 0.17). TCTUs values of patients with AIT were significantly lower (p <0.05; median: 0.9%; range: 0.1-3.2%) than those of patients with GD (median: 5.7%; range: 1.9-28.3%)., Conclusion: In our patients quantitative thyroid scintigraphy with (99m)TcO(4)(-) offered rapid and reliable differentiation between hyperthyroid GD and AIT.

Unlabelled: AIM of this study is the introduction and validation of a simple model of the intrathyroidal iodine kinetics, designed for optimizing radioiodine therapy planning and dose measurement in a routine clinical setting., Methods: The new model defines the intrathyroidal iodine kinetics as balance of the thyroidal iodine intake and -excretion, characterized by the two exponential equations A(t) = A(0) * (1-exp(-lambda(1) t)) and A(t) = A(0) * (exp(-lambda(2) t) -1), respectively. A(0) describes the theoretically maximum iodine uptake when the thyroidal iodine excretion is ignored, lambda(1) and lambda(2) represent the constants characterizing the iodine intake and excretion, respectively. The thyroidal iodine content at the time t equals the sum of both functions, which is A(t) = A(0) * (exp(-lambda(2) t)-exp(-lambda(1) t)). In 25 patients with autonomous goiter / nodules (n = 18), Graves' disease (n = 5), or endemic euthyroid goiter (n = 2), the iodine uptake in the thyroid during the radioiodine therapy as fraction of the applied activity was determined daily, with the remaining body covered by a lead shield. On average, 7.2 measurements were performed per patient (minimum 4, maximum 13). With these uptake values, individual regression curves were fitted using the above equation, and the difference between the actual measurements and the corresponding values of the regression curves was determined., Results: The average deviation of the 179 uptake values from the calculated points of the respective regression curves was only 1.4%. There was no significant difference between the three disease groups. The distribution of the relative deviations during the individual courses was constant, systematic errors were not detected., Conclusion: Our results suggest that the intrathyroidal iodine kinetics can be precisely described with the model A(t) = A(0) * (exp(-lambda(2) t)-exp(-lambda(1) t)). With only three measurements, the trend of the curve can be calculated, which allows to determine the total radioiodine storage in the thyroid.

Introduction: We report on our results of MIVAT operations., Method: Nineteen Patients including 15 females and 4 males were operated with MIVAT, corresponding to 11 % of all patients undergoing an operation for benign goitre in our hospital. A single node of the thyroid gland within 30 mm and enlargement of a thyroid lobe up to 25 ml were the selection criteria. The median age was 34 years (range 16-61). We performed 2 thyroidectomies, 6 Hartley-Dunhill resections, 9 hemihyroidectomies and 2 enucleations. Eighteen patients (95 %) were followed-up postoperatively. The median follow-up period was 8 months (range 1 -21)., Results: The median operation time was 83 min (range 60-124). The median preoperative thyroid gland volume was 25 ml (range 10-54) measured by ultrasound. The resected thyroid tissue ranged from 12 to 51 g (median 29 g). A statistical significant difference (P = 0.04 paired t-test) between the preoperative and postoperative estimated serum-calcium levels (2.31 vs. 2.25 mM) was observed. But both parameters were inside the physiological range. Paresis of the recurrent laryngeal nerve was not observed. 89 % of the patients rated the postoperative cosmetic result as very good and all patients would prefer this operation procedure once again., Conclusion: The MIVAT procedure is a safe operation also in small groups with excellent cosmetic results postoperatively and a high acceptance by the patients.

Objective: We studied the relationship between thyroid volume, thyroid function and immunological markers of Graves' disease (GD) to determine prognostic factors of treatment response to low-dose radioiodine-131 (131I)., Material and Methods: A prospective study of 40 patients with GD hyperthyroidism treated with 131I (141 +/- 85MBq) and 10 GD patients who went spontaneously into remission (controls). Free T4, total T3 and basal TSH levels, TSH-receptor antibodies (TRAb) and anti-thyroid peroxidase antibodies (TPOAb) were studied. Thyroid volume was determined by ultrasonography. Logistic regression models were used to predict the probability of final thyroid status. Receiver-operating characteristics (ROC) curves and Hosmer Lemeshow tests were used to evaluate the final statistical models., Results: Of 40 patients treated with 131I, 16 became euthyroid, 12 hyperthyroid and 12 hypothyroid at 12 months. Median thyroid volume was reduced from 24.8 ml before to 8.5 ml at 12 months (p<0.001). In 10 control patients, the median reduction was from 16.6 ml to 11.3 ml (p=0.029). Thyroid volume reduction was lower in the hyperthyroid than in the euthyroid group, but higher in the hypothyroid group. Thyroid volume at baseline and at 3 months predicted hyperthyroidism outcome with a cut-off of 45 ml and 24.4 ml, respectively (odds ratio 1.074, p=0.003, ROC curve 0.78 and odds ratio 1.182, p=0.012, ROC curve 0.86 respectively). Thyroid volume at 6 months differentiated the hyperthyroid group with a cut-off of 17 ml. Thyroid volume at 3 and 6 months with a cut-off of 8.5 ml and 9.3 ml respectively, predicts permanent hypothyroidism outcome (odds ratio 0.768 and 0.685, p=0.012 and p=0.008, ROC curve 0.89 and 0.88, respectively). Changes in thyroid echogenicity and TRAb and TPOAb levels did not show any predictive value in the follow-up after 131I therapeutic outcome., Conclusion: The study shows that the ultrasonographic thyroid volume at 3 and 6 months after low-dose 131I treatment for GD hyperthyroidism could be a reliable prognostic factor of thyroid function outcome in the first year after treatment, and also reveals that the changes in the thyroid echogenicity and in the immunological markers of GD have no prognostic value.

The version 2 of the procedure guideline for radioiodine test is an update of the guideline published in 1999. The following statements were added or modified: The procedure guideline discusses the pros and cons of a single measurement or of repeated measurements of the iodine-131 uptake and their optimal timing. Different formulas are described when one, two or three values of the radioiodine kinetic are available. The probe with a sodium iodide crystal, alternative or additionally the gamma-camera using the ROI-technique are instrumentations for the measurement of iodine-131 uptake. A possible source of error is an inappropriate measurement (sonography) of the target volume. The patients' preparation includes the withdrawal of antithyroid drugs 2-3 days before radioiodine administration. The patient has to avoid iodine-containing medication and the possibility of additives of iodide in vitamin- or electrolyte-supplementation has to be considered.

Unlabelled: The detection of TSH-receptor antibodies (TRAb) in patients with Graves' disease is routinely used in nuclear medicine laboratories. This determination has been possible for approximately 3 years with a second generation human TRAb assay. Studies showed that this TRAb determination is diagnostically more sensitive compared to established, porcine TRAb assays., Objective: The aim of our study was to investigate, based on a ROC analysis, whether TRAb determination with the new, second generation assay allows a dependable statement about probability of occurrence of relapse after radioiodine therapy in patient suffering from Graves' disease., Methods: 57 patients were examined with the DYNOtest TRAKhuman (BRAHMS Diagnostica AG, Hennigsdorf) directly before and six months after therapy with radioiodine (dose: 150 Gy). A ROC-analysis was performed to determine positive/negative predictive values depending on different cut-off values., Results: Whereas 21/57 patients became eu- or hypothyroid after six months, 36/57 patients relapsed. Non-relapsed patients showed a significant lower median TRAb titer (4.2 IU/l vs. 19.2 IU/l; p <0.05) compared to relapsed patients. But the positive predictive value conducted 63 and 66, 62 and 66 as well as 63 and 69% (before and after therapy) linked with the cut-offs 1.0, 1.5, and 2.0 IU/l. So it was in areas also achieved by the first generation porcine radio receptor assay., Conclusion: An increased sensitivity is achieved undoubtedly with the new DYNOtest TRAKhuman in the diagnostic of Graves' disease. It is not held over the established radio receptor assay concerning the positive predictive value for relapsing patients.

Objective: To report two cases of patients with cerebral vasculitis and Basedow-Graves disease., Case Report: Two young female patients presented at emergency with acute neurological picture of hemiparesis and speech distress. The first patient, 22 year-old, has been on clinical treatment for hyperthyroidism for one month. On clinical examination she had an elevated cardiac rate, bilateral exophthalmia and a diffuse goiter. On neurological examination we could observe a mild dysarthria and left hemiparesis. The second patient was a 15 year-old girl, who presented sudden conscious loss, aphasia and right hemiparesis., Results: CT scan and MRI showed areas of cerebral infarcts. Angiographic study showed multiple vascular stenosis similar to an arteritic angiographic pattern. Extensive medical and laboratorial workout disclosed no other risk factor for stroke or for nervous system vasculitis. The antimicrosomal and antithyreoglobulin antibodies were positive and thyroidian hormones confirmed hyperthyroidism., Conclusion: The concurrence of cerebral arteritis and Basedow-Graves' disease suggest a possible pathogenic link between Graves' disease and specific cerebral vascular disorders, possibly through a common autoimmune mechanism.

Distinguishing Graves' disease (GD) from a toxic multinodular goiter (TMG) subgroup with a diffuse but uneven Tc-distribution depends on the diagnostic power of the TSH-receptor antibody (TRAb) determination. Bioassays using CHO cell lines expressing the hTSH-receptor or a new TBII assay, which uses the hTSH-receptor as an antigen (DYNOTEST TRAK human, Brahms, Germany), showed a higher sensitivity for the detection of TRAbs in patients with GD than assays using solubilized porcine epithelial cell membranes. The aim of this study was to investigate whether the new Dynotest TRAK human assay has an increased sensitivity to distinguish GD from non-autoimmune hyperthyroidism. Therefore, we examined 21 consecutive patients with the initial diagnosis of TMG for thyroid-stimulating antibodies (TSAbs, JP26 cell assay) and TBII with the new highly sensitive Dynotest TRAK human (Brahms, Germany). The initial diagnosis of TMG was based on suppressed TSH and a patchy Tc-uptake of more than 1 % and less than 7 % or TSH of more than 0.3 mIE/l with a patchy Tc-uptake of more than 1.5 % and less than 7 % and negative TBII values in a displacement assay using solubilized porcine epithelial cell membranes (TRAK, Brahms, Germany). 11 sera from these 21 patients showed TSAb activity. Furthermore, 10 of these 11 TSAb-positive sera were also positive in the Dynotest TRAK human assay, whereas one serum sample was borderline positive. TSAb activity and inhibition of (125)I-bTSH binding in the Dynotest TRAK human assay correlated well (r = 0.7). Therefore, 11 of the 21 investigated patients initially classified as TMG actually had GD, which was undetectable using the porcine TBII assay. In conclusion, TSAbs or TRAbs detected with the Dynotest TRAK human have the highest diagnostic power to differentiate GD from TMG. Because of the less cumbersome assay technique, the Dynotest TRAK human measurements should be obtained for all patients with non-typical TMG to differentiate GD from non-autoimmune hyperthyroidism in order to select the appropriate therapy for these patients.

A case of Graves' disease occurring in a patient with hemiagenesis is presented. The detection of the rare occurrence of a congenital hemiagenesis is often made by either clinical symptoms of thyroid dysfunction or anatomical abnormalities such as nodular goiter. The symptoms of hyperthyroidism in the current case led to the diagnostic confirmation by scintiscanning and ultrasonography of an absent lobe. Anti-thyroid antibody studies documented the presence of Graves' disease within the remaining lobe.

Aim: A two-step radioiodine therapy (RITh) is occasionally necessary in patients with benign thyroid disorders, when strong differences to the pretherapeutic radioiodine test occur. In this study, the parameters (uptake and effective half-life of I-131) of the radioiodine test are compared with those of the first and second RITh., Methods: 100 patients were evaluated, who received a two-step RITh in our department between June 1992 and March 1994. Uptake and effective half-life of I-131 and the absorbed dose in the first and second therapy were compared with each other based on the daily measured activity of the thyroid., Results: A two-step RITh was necessary in 10% of the patients. The uptake of I-131 in the first RITh was significantly lower as compared to the test and significantly higher as compared to the second RITh. There were no significant changes between the effective half-life of I-131 in test, first and second RITh., Conclusion: The importance of radioiodine test for the calculation of therapeutic doses is emphasized. The data gathered in our study concerning the diminution of uptake of I-131 in the second RITh can be useful for dose calculation.

Aim: This study evaluates F-18-FDG PET of the thyroid in Graves' disease., Methods: Thirty patients were investigated the day before radioiodine therapy, 15 patients 3-10 days after radioiodine therapy. Twenty patients with cancer of the head or neck and normal thyroid function served as controls., Results: F-18-FDG uptake was higher in Graves' disease patients than in controls. Negative correlations of F-18-FDG uptake with half-life of radioiodine and absorbed radiation dose due to radioiodine therapy were found along with a positive correlation to autoantibody levels., Conclusion: Thus F-18-FDG PET is likely to give information on the biological activity of Graves' disease as well as on early radiation effects.

Estimations regarding the simultaneous occurrence of Graves' ophthalmopathy and autonomously functioning thyroid nodules expect frequencies of 0.05-0.2%. Contrary to these estimated numbers, only 3 patients with these simultaneous manifestations were identified in an out patient thyroid clinic within a period of 10 years. The possible protection by the autonomous thyroid nodules against the manifestations of Graves' disease is discussed.

Aim: The present study deals with the change of the 99mTechnetium-pertechnetate thyroid uptake under suppression (TcTUs) in dependence on the urinary iodine excretion., Methods: The study collective comprises 510 patients with euthyroid goiter (N = 91), with functional thyroid autonomy (N = 361) and with Graves, disease (N = 58), who were examined in the own thyroid ambulance between January 1995 and February 1997 and who presented with endogeneous or exogeneous TSH suppression. All patients received a quantitative thyroid scintigraphy with 99mTechnetium-pertechnetate and a measurement of the urinary iodine excretion., Results: The TcTUs from the whole collective shows an inverse correlation to the urinary iodine excretion for the range of 0 to 500 micrograms iodine/g creatinine. The TcTUs remains constant on a low basal level for iodine excretion values over 500 micrograms iodine/g creatinine. Significant differences occur in dependence on the underlying disease. TcTUs is constantly low in patients with euthyroid goiter, independent of the iodine excretion value. The TcTUs is significantly increased in patients with functional thyroid autonomy or Graves' disease when iodine excretion is below 100 or 50 micrograms iodine/g creatinine respectively, but shows only minor changes when iodine excretion rises up to 500 micrograms iodine/g creatinine. When iodine excretion exceeds 500 micrograms iodine/g creatinine, the TcTUs of patients with thyroid autonomy drops down to a low basal level., Conclusion: The reference range of TcTUs for assessing functional thyroid autonomy will not change significantly when the iodine supply in Germany improves. The TcTUs of patients with functional thyroid autonomy might be up to one third higher under conditions of iodine deficiency than in iodine sufficiency. This should be taken into account, when therapeutical consequences were derived from the TcTUs. The TcTUs cannot be interpreted for iodine excretion values over 500 micrograms iodine/g creatinine.

Purpose: To determine the value and utility of relaxation time measurements with magnetic resonance (MR) imaging in patients with Graves' ophthalmopathy (G.O.)., Materials and Methods: 20 orbits were studied in control subjects and 58 orbits in patients with G.O. T2 relaxation times of extraocular muscles and retrobulbar fat tissue were calculated. The thickness of the eye muscles was correlated with the calculated T2 times. 18 orbits were measured before and after retro-orbital radiation therapy., Results: Upper limits of determined normal T2 values were 60 ms in extraocular eye muscles and 40 ms in retrobulbar fat tissue. 89% (17/19) of the patients with G.O. had prolonged T2 times in extraocular eye muscles. The retrobulbar fat tissue in 5 of 38 orbits revealed minimal edema with the use of fat saturated sequences. T2 relaxation times decreased significantly (p < 10(-4)) after 10 Gy radiation therapy. No correlation was found between enlargement and T2 relaxation times in extraocular eye muscles (r = 0.44 in patients before radiation therapy)., Conclusion: In patients with G.O. the determination of the enlargement of extraocular eye muscles in computed tomography is not a sufficient parameter for an antiinflammatory therapy, since CT cannot visualise eye muscle edema. T2 relaxation time measurements with MR imaging allow differentiation between edematous and fibrotic changes. This is the diagnostic method of choice in patients with Graves' ophthalmopathy.

Aim: We examined the impact of several pretreatment variables on thyroid size and function in 61 patients with Graves' disease one year after a standardized [131]I treatment with 150 Gray., Methods: FT3, FT4, and TSH serum concentrations were determined before and 1.5, 3, 6, and 12 months after therapy. Thyroid size was measured by ultrasound and scintigraphy before and one year after therapy., Results: One year after therapy, 30% of the patients had latent or manifest hyperthyroidism, 24% were euthyroid, and 46% had developed latent or manifest hypothyroidism. Age and initial thyroid volume were major predictors of post-therapeutical thyroid function. Thus, persistent hyperthyroidism was observed in 70% of the patients age 50 years and older with a thyroid size of more than 50 ml. With few exception, thyroid size markedly decreased after therapy. Initial thyroid size and age were also major predictors of posttherapeutical thyroid volume. Thyroid size normalized in all patients younger than 50 years of age, independent from initial thyroid size., Conclusion: Radioiodine treatment with 150 Gray causes a considerable decrease in thyroid size in most patients with Graves' disease. Age and initial thyroid volume are important determinants of thyroid function and size after therapy and should be considered in dose calculation.

Purpose: Assessment of the functional diagnostic value of Doppler sonographic or sonographic parameters, especially of the peak flow velocity in the inferior thyroid artery in patients with newly manifest autoimmunothyroiditis., Material and Method: Morphological and Doppler sonographic measurements were done at the inferior thyroid artery on 69 patients suffering from newly manifest Graves' disease or Hashimoto's thyroiditis, as well as on a control group of 18 subjects. The measured data were correlated with thyroid hormone levels and with quantitative scintiscanning., Results: A linear functional correlation was found between the peak flow velocities in the inferior thyroid artery and the fT3 or fT4 level. If the peak flow velocities were greater than 1.2 m/s, hyperthyroid metabolism prevailed, whereas at velocities below 0.3 m/s latent hypothyroidism was present., Conclusion: These results show that Doppler sonography of the inferior thyroid artery can supply pointers (capable of being recorded) to the state of functioning of the thyroid even before knowing the laboratory parameters.

Unlabelled: A new quantitative subtraction method of thyroid scans is proposed which shows that regional function (F) by far exceeds regional cellularity or cell density (C) in potentially toxic thyroidal areas of non-immunogenic hyperthyroidism (NIH)., Methods: A multistep processing of radioiodine and MIBI thyroid scans of patients with non-immunogenic hyperthyroidism led to normalized images of regional function excess and of perinodular enhancement. Two numeric factors were derived from regions of interest: Q (cell density ratio) comparing MIBI uptake in autonomous and suppressed areas and T (toxicity index): the maximal F/C contrast., Results: Q never exceeded 61; T, however, expanded toxicity levels over a range of 6-8735 with toxic adenomas (median = 165) and with hot areas of multifocal functional autonomy (median = 15). T was weakly correlated to serum TT3 (r = 0.41), but not to autonomous tissue mass, ultrasonographic or cytologic criteria., Conclusions: T is governed by inherent features of autonomous tissue and the response of the imbedded thyroid tissue to TSH stimulation. This standardized technique consolidates experiences from visual analysis; the huge T range mirrors the natural evolution from compensated autonomy towards hyperthyroid, decompensated stages.

Somatostatin receptor scintigraphy with 111In-labeled octreotide proves to be a very sensitive diagnostic tool for evaluation of inflammative activity in endocrine ophthalmopathy (EO). The results of somatostatin receptor scintigraphy (SRS) in 40 patients with EO show a high orbital accumulation of 111In-octreotide in clinically active EO (4 h-median/orbit-brain-ratio: 12.6; controls 4 h-median: 5.8) Patients with clinically inactive EO (4 h-median: 7.1) show a similar orbital accumulation of radioactivity compared to controls. 5 patients with active orbital myositis also revealed an even higher orbital accumulation of radioactivity (4 h-median: 42.3). The diagnostic value of SRS lies in its ability to act as a measure of inflammation and can be useful as an activity parameter when planning therapeutic procedure as well as for EO follow-up. The results in patients with orbital myositis nevertheless do not permit a differential diagnosis with this method. The therapeutic value of 111In-octreotide in Graves' disease has yet to be established.

Recently, [111In]-DTPA-D-phenylalanine-octreotide was introduced for clinical use. This radioligand binds specifically to somatostatin receptors and is suitable for SPECT examinations. The aim of this study was to clarify whether an increased somatostatin receptor density can be imaged and quantified in patients with endocrine ophthalmopathy (e.o.). 7 patients between 34 and 55 years with e.o. at stages III to VI and 4 controls between 38 and 63 years were examined. All patients and controls received approximately 200 MBq [111In]-DTPA-D-phenylalanine-octreotide by IV injection. A SPECT examination was performed 4 hours after injection and a normalised tracer uptake (A(n)) was calculated for both orbitae. In patients with e.o. the values of A(n) were significantly higher compared with controls (P = 0.002). There was a correlation between A(n) and exophthalmus stages according to Hertel with r = 0.844 (P = 0.001). These results indicate that [111In]-DTPA-D-phenylalanine-octreotide SPECT might be useful for the in vivo assessment of an increased somatostatin receptor density in e.o. These findings could have an impact on the treatment with somatostatin analogous in e.o.

The aim of this study was to determine the significance of the radioiodine uptake test for predicting the kinetics of therapeutic 131I doses in the treatment of benign thyroid disorders. We studied retrospectively the histories of 518 consecutive patients treated with 131I for hyperthyroidism or autonomous thyroid goiter, with respect to uptake and effective half-life of tracer and therapeutic doses. The mean half-life and uptake of the therapeutic doses were significantly smaller than that of the tracer dose. A comparison of different methods of calculation showed that the radioiodine uptake test is indispensible for dose calculation in radioiodine treatment but a single measurement after 24 or 48 h is sufficiently accurate because, on average, the therapeutic dose was achieved as planned and with the smallest scatter. Average half-lives specific to the disease to be treated may be used in the calculations.

Author reports on 2 women, 42 respectively 58 years old, with Graves' Ophthalmopathy. In both cases acute considerable change of refraction was noticed: progression of preexistent myopia. Author suggests edema and infiltration of lymphocytes and plasmacyts of ciliary-body, pathologic-anatomical substratum of the most changes of orbita in this disease, responsible for etiology.

The thyroid metabolism has to be treated first. If this is not followed by regression of the exophthalmos, treatment with prednisone over a period of several weeks is indicated. If this does not result in permanent improvement, surgical decompression of the orbit is indicated, especially if the exposition of the cornea or compression of the optic nerve represent an imminent danger. In such cases surgical decompression is preferable to multiple series of prednisone or radiation treatment (Wright 1981, Trokel 1982). Both the Krönlein-Berke operation for resection of the lateral orbital wall as well as neurosurgical resection of the orbital roof have proved to be excellent for removal of correspondingly located orbital tumors; effective decompression of the orbit in malignant endocrine exophthalmos, however, cannot be achieved this way, as the temporal muscle and the brain, respectively, prevent protrusion of the swollen orbital tissues through these apertures. Resection of the orbital floor is somewhat more effective. The mucosa of the maxillary sinus can easily be moved by the protruding orbital tissues, resulting in a reduction in the size of the maxillary sinus. This decompression, however, is effective only in the anterior two-thirds of the orbit, while the optic nerve must be relieved from the pressure of the swollen muscles in particular in the posterior one-third of the orbit. The only effective way is to remove the medical orbital wall up to the tip of the orbit. Surgical techniques for this purpose have already been recommended, but appeared unsatisfactory from a rhinological point of view.(ABSTRACT TRUNCATED AT 250 WORDS)

Radio-iodide diagnosis of the thyroid is a simple method of high security in the diagnosis of endocrine ophthalmopathy. This procedure is valuable especially, in cases where neither clinically, nor in the sero-hormonal diagnosis a disturbance of the thyroid can be found. In many cases an accelerated intrathyroidal turnover of radio-iodide can identify an unclear ophthalmopathy as an endocrine ophthalmopathy. The therapy of choice for hyperthyreoidism with endocrine ophthalmopathy is 131-iodide resection. This statement has been proven by our own experiences in more than 1000 cases in the past 15 years and by the results indicated in early literature about the course of ophthalmopathy after surgical or medical treatment. For the therapy of a malign, or imminent malign endocrine ophthalmopathy, we use percutane irradiation of the orbit with sparing of the lens in a dose of 200 rad 5 times a week. In practically all cases, this therapy eliminates the consequence of visual disturbances and avoids surgical decompression.

CT scans of 25 clinically typical cases of Graves' disease and 15 cases of orbital pseudotumor (idiopathic orbital inflammation) are analyzed and differential diagnostic criteria evaluated. The CT-findings overlap and are best viewed as a continuous spectrum at both ends of which characteristic patterns can be identified. Massive swelling of ocular muscles, involving of several muscles, usually without density changes of the orbital fat, are diagnostic for Graves' disease. More or less circumscribed masses of soft tissue density surrounding the globe, eye muscles or the optic nerve, severe diffuse increase of density in the retrobulbar space masking orbital structures and calcifications indicate orbital pseudotumor. Localization of the swelling within a muscle, "scleral thickening", enhanced contrast, moderate density changes of the orbital fat, and involvement of the lacrimal gland are of minor differential diagnostic value. CT pictures of clinically typical and histologically proven cases of Graves' disease indicate heterogeneity of this group, probably reflecting different immunologic features. CT shows the extent and degree of the pathologic changes and indicates the optimal approach for tissue biopsy. Evaluation of both diseases by CT requires inclusion of coronal sections.

There now exist protocols for specific scanning which make it possible to obtain tranverse sections of a few millimetres in thickness of the orbits and their contents, with minimum sweep and with a very low dose of radiation for the lens. Normal scanner anatomical findings in the orbit may thus be defined for the eyeball (outer coats, vitreous, lens) as well as retrobulbar structures (optic nerve, oculomotor muscles in particular). Intraocular tumours (e.g. retinoblastoma) are visible on enlarged scan films. The value of scannings lies above all in the determination of the site, size and shape of orbital lesions and, where applicable, their relations with neighbouring extra- and intra-cerebral structures. In addition, certain conditions such as exophthalmos during hyperthyroidism have characteristic scan findings. It nevertheless remains difficult to attempt to predict a histological diagnosis on the basis of scan findings, the risk of a false positive being particularly significant. Particular emphasis must be placed upon the contribution of techniques of treatment of the films obtained (enlargement, contrast media, histograms, lateral views) as well as the complementary use of other methods of radiological investigation (in particular arteriography and phlebography) which scanning cannot replace but which it should usually precede since it is atraumatic and non-invase.

The value of scanning lies above all in the determination of the site, size and shape of orbital lesions and, where applicable, their relations with neighbouring extra or intra cerebral structures. But certain conditions such as exophthalmos during hyperthyroïdosis have characteristic scan findings. Even intra-ocular tumors are visible on elarged scanfilms. It nevertheless remains difficult to attempt to predict a histological diagnosis on the only basis of scan findings. Particular emphasis must be placed upon the contribution of techniques of treatment of the films obtained (enlargement, contrast media, histograms, lateral views) as well as the complementary use of phlebography and ultrasonography.

The volumes of the four recti muscles and the orbital fat was measured by CT in 40 normal persons and in 60 patients with clinically confirmed Graves' disease. Compared with normal persons, 42 patients (70%) showed an increase in muscle volume and 28 patients (46.7%) an increase in the amount of fat. In nine patients (15%) muscle volume was normal, but the fat was increased. By using volumetric measurements, the amount of fat in the orbits in patients with Graves' disease could be determined.

The correlation between the loss of function of the extrinsic rectus eyemuscles and their appearance on computed tomography images in patients with Graves' disease was examined. Pathologic changes of a single rectus eyemuscle normally blockade the movement of the corresponding antagonistic muscle. This is caused by the impossibility to relax due to fibrotic alterations. Nevertheless there are some hints, which indicate, that in some cases, especially concerning the lateral rectus muscle, the inherent function of the thickened muscle is restricted.

In 255 patients (normals: group I, n = 30; nontoxic goitres: group II, n = 134; toxic goitres without ophthalmopathy: group III, n = 63; Graves' disease: group IV, n = 28) a TSH-receptor-autoantibody-assay (TRAK assay) for detection of thyrotropin-binding inhibiting antibodies (TBIAb) was tested and 99mTcO4-uptake (TcTU) was measured. Normal TcTU (range: 1.5-5.5%) and normal TRAK values (normal limit: F less than 11%) were only found in group I. An increased TcTU was found in group II in 22.4% (increased TRAK values only in 2.2%). In group III an increased TcTU was measured in 34.9% of the patients (all with normal TRAK titers). The stimulation of the TSH-receptor in immunogenic hyperthyroidism by TBIAb could be demonstrated by increased TRAK values in 71.4% of the patients with Graves' disease. In correlation, TcTU was also increased in 82.1% of the patients in group IV. As the measurement of TcTU can be helpful in differential diagnosis, the functional imaging with gamma camera and computer is today a conditio sine qua non, especially in suspected hyperthyroidism.

The treatment of Graves' ophthalmopathy is symptomatic because the etiology remains unknown though evidence supports an aberrant immune response. Orbital radiotherapy, combined with corticosteroids, is indicated for rapidly progressive ophthalmopathy and troublesome soft tissue symptoms. In case of sight-threatening manifestations operative decompression is the method of choice. However, radiotherapy seems to be a safe and effective method as a good to excellent response in 60-70% of patients can be expected. The treatment results of 15 patients with a long term follow-up are presented.