Utilidad de la imagen combinada de PET/TC con 68Ga-DOTATOC y gammagrafía de bazo para la diferenciación entre tumor neuroendocrino de la cola del páncreas y lesiones esplénicas en un paciente con esplenosis post-traumática / Usefulness of combined imaging with 68Ga-DOTATOC PET/CT and spleen scintigraphy in differentiating a neuroendocrine tumour of the pancreatic tail from splenic lesions in a patient with posttraumatic splenosis

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Bone mineral density and bone metabolism in patients with major depressive disorder without somatic comorbidities.

BACKGROUND: Major depressive disorder (MDD) has been linked with accelerated bone loss leading to the development of low bone mineral density (BMD). Several mechanisms have been discussed as causative factors, e.g. lifestyle, selective serotonin reuptake inhibitor (SSRI) intake, or the influence of proinflammatory cytokines. METHODS: In a cross-sectional study of in-patients with a current episode of MDD, without somatic comorbidities, we determined various parameters of bone metabolism, inflammatory parameters and parameters of depression. BMD was measured by dual x-ray absorptiometry. RESULTS: Of 50 patients, only one had low BMD in any of the measure sites. Body mass index (BMI) correlated positively with Z-scores. 83.3% of the examined patients had elevated osteoprotegerin (OPG) levels. SSRI intake did not have an effect on BMD. BMD in the femoral neck was significantly lower in smokers. We also found a positive correlation between the level of physical activity and osteocalcin levels. CONCLUSIONS: In our sample, young to middle-aged, somatically healthy, and acutely depressed patients with a history of MDD showed no reduction of BMD. This could be due to compensatory mechanisms, as suggested by elevated OPG levels. Physical activity and high BMI could also have served as protective factors. Still, as patients with MDD often suffer from comorbidities or take medication with a negative effect on bone, this population should be appreciated as a high-risk group for the development of osteopenia and osteoporosis.

Z-score comparability of bone mineral density reference databases for children.

PURPOSE: The diversity of pediatric dual-energy x-ray absorptiometry (DXA) bone mineral density (BMD) reference databases raises questions as to whether they are interchangeable in their application. This study examined the comparability of BMD Z-scores generated from the largest available Hologic DXA databases, applied on BMD results of a large series of unselected pediatric patients. METHODS: A total of 2027 BMD scans were extracted from Hologic QDR-4500A machines. Age- and sex-specific BMD Z-scores of children aged 8-17 yr, calculated from six Hologic databases, were compared for lumbar spine (LS) and total body (TB). The final dataset included 708 scans (307 of girls). RESULTS: BMD Z-scores calculated from the six databases were highly correlated but differed significantly (P < 0.001) in both scan regions. Interdatabase Z-score differences (boys/girls, respectively) were up to 0.54/0.55 for LS and 1.0/0.83 for TB. These differences also varied significantly among age groups. In girls, the percentage of LS BMD Z-scores of -2 or below ("low BMD for age") varied between 15.4 and 27.9% (P < 0.012). The percentage of TB BMD Z-scores of -2 or below varied similarly in boys (P < 0.009). CONCLUSIONS: Clinically relevant differences in BMD Z-scores exist between the Hologic databases, revealing a significant potential for misdiagnosis. Ideally, Z-scores should be calculated using model-, brand-, and software-specific reference curves for age, sex, and ethnic group. However, our results can be used to estimate converted values. There are other differences in children's bone mass, shape, strength, and body size that are not detected by DXA.

Use of the European preliminary criteria, the Breiman-classification tree and the American-European criteria for diagnosis of primary Sjögren's Syndrome in daily practice: a retrospective analysis.

This study was conducted to assess the use of the European preliminary criteria, the Breiman-classification tree and the American-European criteria for diagnosis of primary Sjögren's Syndrome (pSS) in daily practice. A retrospective analysis of 17 consecutive patients with pSS (European criteria) was performed evaluating the application of the Schirmer test, semiquantitative sialoscintigraphy, immunologic tests, including rheumatoid factor, antinuclear antibodies, Sjögren's syndrome autoantibodies (SS-A, SS-B) and lip biopsy. Out of the 17 patients with pSS according to the European criteria, 15 patients fulfilled the classification tree (=88.2%), and 4 patients fulfilled the American-European criteria (=23.5%, P = 0.001). In the four patients fulfilling the American-European criteria, a positive result of the sialoscintigraphy was not crucial for the diagnosis according to these criteria. In conclusion, the American-European criteria are more stringent than the European preliminary criteria. We assume the role of sialoscintigraphy to be reduced when applying the American-European criteria.

99mTc-EDDA/HYNIC-Tyr(3)-octreotide for staging and follow-up of patients with neuroendocrine gastro-entero-pancreatic tumors.

AIM: To evaluate the use of 99mTc-EDDA-hydrazinonicotinyl-Tyr3-octreotide (Tc-TOC) for staging and follow-up of neuroendocrine gastro-entero-pancreatic (GEP) tumors with special focus on the acquisition protocol including single photon emission computed tomography (SPECT). METHODS: Eighty-eight patients (37 female, 51 male; age range: 16 to 81 years; mean age: 56.3 years) were studied: 42 patients for staging after initial histological confirmation and 46 patients during post-therapy follow-up. An average activity of 400 MBq of the radiopharmaceutical was injected. All tumors originated from neuroendocrine tissue of the gastroenteropancreatic tract. Whole body scintigrams at 4 h postinjection and SPECT of the abdomen were obtained in all patients. Additional planar images of the abdomen were acquired at 2 h after injection in 68 patients. RESULTS: The Tc-TOC scan result was true-positive in 56 patients, true-negative in 17, false-negative in 14, and false-positive in 1 patient. The false-positive finding was caused by a colonic adenoma. Overall, a scan sensitivity of 80% (56/70 patients), specificity of 94.4% (17/18 patients) and accuracy of 82.9% (73/88 patients) were calculated on patient basis. In total, Tc-TOC detected 357 foci in 69 patients. In 7 patients equivocal findings were observed in the bowel at 4 h postinjection without corresponding tracer uptake in the scan 2 h earlier, meaning that these abnormal findings were correctly classified as non-malignant. In addition to planar views, SPECT revealed further 62 lesions. CONCLUSIONS: Tc-TOC with one-day, dual-time acquisition protocol is an accurate staging procedure in patients with neuroendocrine GEP tumors. SPECT shows high sensitivity for detection of abdominal lesions, while earlier images improve the reliability of abnormal abdominal findings.

Position of nuclear medicine techniques in the diagnostic work-up of brain tumors.

Although any patient with a suspected brain tumor, either primary or metastatic, should be studied with anatomic imaging modalities such as angiography, computerized tomagraphy (CT) or magnetic resonance imaging (MRI), nuclear medicine techniques are available to further characterize some biological features of brain lesions and help in diagnosis and therapy planning. Bloob-brain-barrier disruption can be easily assessed with single-photon emission tomography (SPET), whereas focal metabolic changes can be better demonstrated by positron emission tomography (PET) as specific radiopharmaceuticals are available to detect changes in glucose utilization and aminoacid uptake with this technique. Expression of specific tumoral antigens is the basis of imaging with radioimmunoscintigraphy, a promising technique that can be applied to brain tumor therapy. The major clinical applications of nuclear medicine in the study of brain tumors -- evaluation of the extension of a tumoral mass, differential diagnosis and evaluation of therapy and prognosis -- are discussed.

Nuclear medicine in diagnosis, staging and follow-up of thyroid cancer.

Diagnostic strategy in thyroid cancer is conditioned by epidemiological, pathophysiological, cost-effective issues changing with age and countries. Nuclear medicine has a role mainly in differentiated carcinomas, i.e. in the large majority of thyroid cancers. In diagnosis of thyroid nodule (99m)Tc-perthecnetate is indicated in patients with low TSH levels, multinodular goiter, solid nodules at US negative at FNA. Radiolabeled somatostatin analogs or Metaiodobenzylguanidine (MIBG) can be used in suspicion of medullary carcinoma. There is no role in staging. WBS with 131I has a role after surgical resection of the thyroid gland and it is no more suggested before ablative therapy, because of the possible stunning effect. In the follow-up thyroglobulin (Tg) test is mandatory both after therapy withdrawal or after rhTSH administration. Some authors already suggest to use this test alone, as 1st step, in patients with differentiated carcinoma at low risk of recurrence, but this approach is not yet generally accepted and it has not yet been validated in tumors at intermediate/high risk. WBS with 131I is ever indicated when autoantibodies can affect reliability of Tg values and in presence of high Tg levels to better define a radiometabolic therapy. In case of negative WBS, PET-FDG can be proposed. In WBS, 123I can be an alternative to 131I, but it is not yet generally accepted mainly because of its higher costs. The clinical use of rhTSH to increase accuracy both of Tg and WBS can be already accepted in patients at high risk following hypothyroidism, with a worst prognosis or a low pituitary response.

Evidence for interaction between the TCO and NMTC1 loci in familial non-medullary thyroid cancer.

BACKGROUND: Familial non-medullary thyroid cancer (fNMTC) is a complex genetic disorder that is more aggressive than its sporadic counterpart. Thus far, three genetic loci have been implicated in susceptibility to fNMTC by linkage analysis. METHODS: We used linkage analysis to test the significance of two of the known susceptibility loci for fNMTC, TCO on 19p13 and NMTC1 on 2q21 in 10 fNMTC families, nine of which present with cell oxyphilia, a rare histological phenotype associated with TCO. Furthermore, we used two-locus linkage analysis to examine the possibility that the TCO and NMTC1 loci interact to increase the risk of NMTC. RESULTS: The 10 families provided evidence for linkage at both TCO and NMTC, with LOD scores of 1.56 and 2.85, respectively. Two-locus linkage analysis, using a multiplicative risk model for the development of NMTC, achieved a maximum LOD of 3.92, with an LOD of 4.51 when assuming 70% of families were linked, indicating that the segregation in these families is consistent with an interaction model. Most of this evidence came from a large Tyrolean family that singularly achieved a two-locus LOD of 3.21. CONCLUSIONS: These results provide further evidence that susceptibility genes for fNMTC exist at 19p13 and 2q21, and furthermore, raise the possibility that in a subset of fNMTC pedigrees, these loci interact resulting in significantly increased risk of NMTC for patients that carry both susceptibility loci.

[Lymph node tuberculosis in a patient with polymyalgic symptoms: value of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET)]. / Lymphknotentuberkulose bei Polymyalgie-ähnlichem Syndrom: Wert der 18F-Fluorodeoxyglucose Positron Emissions Tomographie (18F-FDG-PET).

18F-FDG-PET studies were performed in a 60-year-old female patient with polymyalgia rheumatica resistant to prior corticosteroid treatment. PET studies showed a cervical focus, which was identified histologically and microbiologically as lymph node tuberculosis.

18F-fluorodeoxyglucose-positron emission tomography: a new explorative perspective.

18F-Fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) is a new functional imaging technique available for clinical and experimental use. 18F-FDG-PET studies can be used for screening, localization and follow-up of hypermetabolic processes including malignancies, infections and autoimmune processes. For several years it has been applied in oncological, cardiological and neurological patients, but nowadays an increasing number of studies favours its use in patients with autoimmune diseases including large vessel arteritis. From the experimental view, this technique has even become more important since the introduction of a small PET scanner for the use in animal models. This review focuses on technical aspects, clinical experiences and experimental and future perspectives of 18F-FDG-PET, with a special emphasis on large vessel vasculitis and other autoimmune diseases.

[Diagnosis and therapy of Graves' ophthalmopathy--consensus guidelines]. / Diagnostik und Therapie der endokrinen Orbitopathie--Konsensusrichtlinien.

On 22-09-2001 the VIth Grazer Hormonsymposion took place. Diagnosis and therapy of Graves' Ophthalmopathy was discussed in an interdisciplinary way by endocrinologists, surgeons and ophthalmologists. The results of the round-table discussion and the consensus talk are presented.

Mania caused by a diencephalic lesion.

We describe the case of a young male patient, SN, who suffered a MR-documented ischaemic lesion of both dorsomedial thalami and presented with a transient maniform syndrome. SN's neuropsychological, structural and functional imaging findings are compared with similar reported cases and are discussed in the framework of fronto-subcortical circuits and their proposed behavioural disorders. SN's mania was characterized by restlessness, mood elevation, a tendency for pleasurable activities, inflated self-esteem and loss of disease awareness. Other symptoms were sexual disinhibition, tactlessness, abnormal discourse, and reduced need for food and sleep. His neuropsychological assessment revealed an anterograde amnesia, and an impairment of frontal-executive functions. A SPECT-study showed diaschisis-related areas of hypoperfusion in both prefrontal regions which were interpreted as equivalents of SN's frontal-dysexecutive syndrome. In addition, there was a perfusion deficit in the right orbitofrontal cortex, which was taken as the imaging correlate of SN's secondary mania and personality disorder. These findings suggest that SN's mania and his other symptoms result from the twofold disruption of fronto-subcortical connections, namely of the right orbitofrontal loop which is concerned with mood regulation and socially appropriate behaviour, and of the dorsolateral prefrontal loop which mediates executive cognitive functions.

Improved scintigraphic assessment of occult leakages in adjustable gastric bands using 99mTc-labelled human albumin colloid.

BACKGROUND: Adjustable gastric banding has become the preferred procedure in Europe for the treatment of morbid obesity. A complication of this treatment is the presence of leakage in the system. The knowledge of the localization of the leak is essential for planning the reoperation procedure. PATIENTS AND METHODS: In a series of 325 adjustable gastric bandings, we observed 10 band leakages. In 3 cases, fluoroscopy failed to detect fluid extravasation. We present a sensitive and simple scintigraphic method for the detection of gastric band leakage in these patients using 37 MBq of a 99mTc-human albumin colloid suspension. Imaging was started immediately after the dose application. During the first minute, images were acquired dynamically with 1 frame every 2 seconds. Afterwards, a static image was obtained every 10 minutes, up to 60 minutes post-injection. Then the system was emptied completely to detect tracer extravasation and consecutive reabsorption during 60 minutes. The study was analyzed by using the regions of interest (ROI) technique drawn on the following points: injection reservoir, tube, anterior band, posterior band, and an adjacent region which was taken as background. RESULTS: During the first hour, ROI analysis showed a clear diminution in the number of counts contained in the defect parts of the band, whereas it remained constant in the other locations. After system emptying, detection of tracer extravasation further strengthened the diagnosis of band leakage in all patients. CONCLUSION: This new approach using the 99mTc-human albumin colloid suspension with ROI analysis is an effective and simple method to detect occult leakages in adjustable gastric bands which escaped detection by fluoroscopy. In contrast to previously described scintigraphic methods, this investigation is able to demonstrate the exact site of leakage.

Detection of myocardial involvement in systemic lupus erythematosus: mismatch between normal perfusion scans with 201Thallium and pathological 18FDG uptake.

BACKGROUND: Systemic lupus erythematosus (SLE) patients can frequently present cardiac symptoms, however its etiology is not well known. EXPERIMENTAL DESIGN: prospective study. SETTINGS: specialized out-patient unit for SLE patients at an university hospital. PATIENTS: 15 SLE patients (13 females, 2 males; age range 18-64 years). INTERVENTIONS: metabolic studies of the heart were done using 18F-deoxy-glucose (18FDG, 296-333 MBq on a 2-head hybrid system) as well as heart perfusion studies (111MBq 201Tl). Additional studies: resting ECG, echocardiography, stress ECG, immunological activity parameters, antibody analyses (ANA, ENA, anti-cardiolipin antibodies), CPK, troponin-T, and lipid profiles. MEASURES: degree of correlation between conventional diagnostics and the imaging techniques. RESULTS: Abnormal ECG in 10 cases, pericardial involvement in 11 cases, elevated CPK in 1 case. ANTIBODY PROFILES: anti-cardiolipin in 10/15, ENA in 9/15, ANA in 14/15. None of these changes were associated with parameters of immune activation. In the majority of cases (10/15) the 18FDG scan showed a speckled, inhomogeneous pattern of distribution, which contrasted sharply with a normal 201Tl scan. A similar pattern was observed in the patients with ocular mitochondrial myopathy, the anti-phospholipid syndrome as well as in dermatomyositis. CONCLUSIONS: Our preliminary results suggest that SLE patients with cardiac symptoms may have an abnormal glucose metabolism of the myocardium as shown by a pathological 18FDG scan, whereas perfusion appears to be normal (reversed mismatch). The lack of correlation with acute elevation of cardiac enzymes or with ECG changes suggest a chronic process.

99mTc-EDDA/HYNIC-TOC: a new 99mTc-labelled radiopharmaceutical for imaging somatostatin receptor-positive tumours; first clinical results and intra-patient comparison with 111In-labelled octreotide derivatives.

[111In-diethylene triamine penta-acetic acid-D-Phe1]-octreotide (DTPA-octreotide) scintigraphy has gained widespread acceptance as a diagnostic clinical procedure in oncology for imaging somatostatin receptor-positive tumours. However, indium-111 as a radiolabel has several drawbacks, including limited availability, suboptimal gamma energy and high radiation burden to the patient. We have recently reported on the preclinical development of 99mTc-EDDA/HYNIC-TOC, a new octreotide derivative which showed promising results both in vitro and in vivo. We now report our initial clinical experiences with this new radiopharmaceutical in ten oncological patients. The clinical diagnoses were: carcinoid syndrome (n=5), thyroid cancer (n=3), pancreatic cancer (n=1) and pituitary tumour (n=1). The biodistribution and kinetics of 99mTc-EDDA/HYNIC-TOC were compared with those of 111In-DTPA-octreotide in six cases, and with those of 111In-DOTA-TOC in five cases. With the new tracer tumours were imaged within 15 min after injection and showed the highest target/non-target ratios 4 h after injection. Tumour uptake persisted up to 20 h p.i. The rate of blood clearance was similar to that of 111In-DTPA-octreotide but faster than that of 111In-DOTA-TOC, while urinary excretion was lower compared with the 111In derivatives. Semi-quantitative region of interest analysis showed that 99mTc-EDDA/HYNIC-TOC produced higher tumour/organ (target/non-target) ratios than the 111In derivatives, especially in relation to heart and muscle. Significantly more lesions could be detected in 99mTc images. We conclude that 99mTcEDDA/HYNIC-TOC shows better imaging properties for the identification of somatostatin receptor-positive tumour sites than currently available 111In-labelled octreotide derivatives.