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J Meller

Publications and source records attributed to J Meller.

At least 19 recordsLinked to original sources
PubMed2006

Growth hormone response in low-dose apomorphine test correlates with nigrostriatal dopamine transporter binding in patients with Parkinson's disease.

Challenge with low-dose apomorphine causes a rise in growth hormone (GH) in patients with Parkinson's disease (PD). We studied 18 patients with early PD, who showed an increase of GH in the low-dose apomorphine test, by means of [(123)I] FP-CIT-SPECT. The mean specific dopamine transporter binding of the 18 patients was 1.50 +/- 0.56 in the striatum, 1.20 +/- 0.59 in the putamen, and 1.76 +/- 0.59 in the caudate nucleus. The increase of GH (1.05 +/- 1.01 ng/ml at baseline to 9.46 +/- 6.36 ng/ml 45 min after apomorphine injection; p < 0.001) was significant. There was a significant negative correlation of the increase of GH with the mean specific dopamine transporter binding in all three regions (r between -0.490 and -0.587; p between 0.04 and 0.01). Challenge with low-dose apomorphine may therefore be used as an indirect tool to measure the extent of nigrostriatal neurodegeneration in early PD.

Adult↗
PubMed2006

Incidence of radioiodine induced Graves' disease in patients with multinodular toxic goiter.

In this study, we assessed the incidence of Graves' disease (GD) following radioiodine therapy (RIT) in a large cohort of well characterized patients with autonomy in comparison to the clinical course of control patients with thyroidal autonomy not definitively treated with (131)I or surgery. 622 consecutive patients were treated with (131)I for autonomy (unifocal: n = 321; multifocal: n = 199; disseminated: n = 102) and followed up for at least 6 months post RIT. 108 consecutive patients with autonomy not definitively treated (unifocal: n = 49; multifocal: n = 42; disseminated: n = 11) followed up for at least 6 months served as controls. Initial evaluation and follow-up included determination of FT3, FT4, TSH, autoantibodies against the thyroid peroxidase (anti-TPO) and TSH-receptor antibodies (TRAb) by highly sensitive radio receptor-assay, quantitative thyroid scintigraphy and sonography. After 6 months, GD was newly diagnosed in 1/321 patients with unifocal autonomy, in 1/199 patients with multifocal autonomy and in 0/108 control patients. In patients with disseminated autonomy (group C), GD was diagnosed significantly more often compared to the other groups (5/102 patients; 4,1 %; p < 0.05). In conclusion, RIT may induce Graves' disease in a few cases with toxic multinodular goiter. The incidence in this population is small. Compared with patients suffering from uni- or multifocal autonomy, subjects with disseminated autonomy have a more than tenfold higher risk for the development of GD.

Adult↗
PubMed2006

[Improvement of tomographic reconstruction in bone SPECT].

AIM: The comparison between iterative reconstruction and filtered backprojection in the reconstruction of bone SPECT in the diagnosis of skeletal metastases. PATIENTS, METHODS: 47 consecutive patients (vertebral segments: n = 435), with suspected malignancy of the vertebral column, were examined by bone scintigraphy and MRI (maximal interval between the two procedures +/- 5 weeks). The SPECT-data were reconstructed with an iterative algorithm (ISA) and with filtered backprojection. We defined semiquantitative criteria in order to assess the quality of the tomograms. Conventional reconstruction was performed both by a Wiener-filter and a low-pass-filter. Iterative reconstruction was performed by the ISA algorithm. The clinical evaluation of the different reconstruction algorithms was performed by MRI as the gold-standard. RESULTS: Sensitivity (%): 87.3 (ISA), 86.4 (low-pass), 79.7 (Wiener); specificity (%): 95.3 (ISA), 95 (low-pass), 85.4 (Wiener). The sensitivity of iterative reconstructed SPECT and low-pass reconstructed SPECT was significantly higher (p < 0.05) compared with the sensitivity of SPECT reconstructed by the Wiener-filter. The specificity of iterative reconstruction ISA and low-pass-filter reconstructed SPECT were significantly higher compared with the SPECT data reconstructed by the Wiener-filter. ISA was significantly superior to the Wiener-SPECT relating to all criteria of quality. Iterative reconstruction was significantly superior to the low-pass-SPECT relating to 2 of 3 criteria. In addition the Wiener-SPECT was significantly inferior to the low-pass-SPECT regarding to 2 of 3 criteria. CONCLUSION: In our series the iterative algorithm ISA was the method of choice in the reconstruction of bone SPECT data. In comparison with conventional algorithms ISA offers a significantly higher quality of the tomograms and yields a high diagnostic accuracy.

Female↗
PubMed2005

Expression of the sodium iodide symporter in differentiated thyroid cancer: clinical evidence.

AIM: Molecular analysis of the expression of the sodium iodide symporter (NIS) in 32 patients with differentiated thyroid cancer (DTC) and correlation with scintigraphic findings ((131)I,(123)I) in 19 (59.4%) of them. PATIENTS, METHODS: NIS expression of 27 primary tumours, 13 lymphnodes and 18 distant metastases was determined by immunostaining using a murine monoclonal anti-NIS-antibody. NIS expression and radionuclide uptake of metastases were analysed by a semiquantitative visual score. Patients were divided into two subgroups: Group 1 (n = 8 patients): indirect correlation of radioiodine uptake (RIU) of subsequent metastases with NIS expression of 7 primary tumours and 3 metastases; Group 2 (n=11 patients): direct correlation of radionuclide uptake with NIS expression of 19 metastases which were excised after imaging. RESULTS: 49 of 58 specimens (84.5%) were NIS-positive. A preserved NIS-expression was found in 12 primary tumours and 8 of 10 (80%) synchrone and 6 of 7 (85.7%) metachrone metastases. Group 1 revealed a 100% positive predictive value (PPV) of a preserved NIS expression in the primary tumour regarding radioiodine uptake in metastases while a lack of NIS expression in the primary tumor did not reliable predict a loss of the metastases' ability to concentrate radioiodine. In group 2, only 11 of 19 (57.9%) specimens showed a concordant NIS expression and RIU whereas in the remaining 8 cases without visible RIU NIS expression was still present. CONCLUSIONS: NIS expression of the primary tumour and metastases in DTC is usually well preserved. We found a positive correlation between NIS expression of the primary and metastatic tissue but could not identify such well correspondence between NIS expression and the RIU of subsequent metastases.

Adult↗
PubMed2005

Diagnostic 123I and 131I activities and radioiodine therapy. Effects on urinary iodine excretion in patients with differentiated thyroid carcinoma.

AIM: Urinary iodine excretion (UIE) provides information about iodine supply and release. In the present study we investigated effects of the application of different radioiodine isotopes on UIE in patients with differentiated thyroid carcinoma (DTC). PATIENTS, METHODS: In 91 consecutive patients with DTC UIE, measured as iodine/creatinine ratio, was determined before and after application of 123I and 131I for diagnostic or therapeutic purposes. Additionally, remnant volume (V) was determined prior to therapy. Group A consisted of 33 patients with supposed successful ablation of DTC. These patients received 370 MBq 131I for diagnostic use and served as controls. 58 patients (group B) with remnants, relapses and metastases received 370 MBq 123I for diagnostics prior to therapy with 1.5-22.2 GBq 131I. Factors influencing individual changes in urinary iodine excretion (deltaUIE) were investigated by using non-parametric tests. RESULTS: In group A UIE did not change significantly after application of 131I. As well, UIE remained unchanged after diagnostic application of 123I in group B. In contrast, UIE increased significantly already 24 h after therapeutic application of 131I in this group. In patients with small remnants (V < 2.5 ml) a significant but only moderate increase of UIE could be observed (average increase: 47 microg I/g crea). In patients with larger remnants, with relapses or metastases increase of UIE values was significant and more pronounced. CONCLUSIONS: It was confirmed that UIE increased significantly during radioiodine therapy in patients with DTC and radioiodine-accumulating tissue. The increase of UIE after therapeutic administration of radioiodine can be explained by the disintegrated thyroid follicles in thyroid remnants. The radioiodine-induced iodine release may be one reason for thyroid "stunning" even after application of diagnostic amounts of 131I.

Creatinine↗
PubMed2004

Erythropoietin: a candidate compound for neuroprotection in schizophrenia.

Erythropoietin (EPO) is a candidate compound for neuroprotection in human brain disease capable of combating a spectrum of pathophysiological processes operational during the progression of schizophrenic psychosis. The purpose of the present study was to prepare the ground for its application in a first neuroprotective add-on strategy in schizophrenia, aiming at improvement of cognitive brain function as well as prevention/slowing of degenerative processes. Using rodent studies, primary hippocampal neurons in culture, immunohistochemical analysis of human post-mortem brain tissue and nuclear imaging technology in man, we demonstrate that: (1) peripherally applied recombinant human (rh) EPO penetrates into the brain efficiently both in rat and humans, (2) rhEPO is enriched intracranially in healthy men and more distinctly in schizophrenic patients, (3) EPO receptors are densely expressed in hippocampus and cortex of schizophrenic subjects but distinctly less in controls, (4) rhEPO attenuates the haloperidol-induced neuronal death in vitro, and (4) peripherally administered rhEPO enhances cognitive functioning in mice in the context of an aversion task involving cortical and subcortical pathways presumably affected in schizophrenia. These observations, together with the known safety of rhEPO, render it an interesting compound for neuroprotective add-on strategies in schizophrenia and other human diseases characterized by a progressive decline in cognitive performance.

Adult↗
PubMed2004

Diagnosis and follow up of aortitis in the elderly.

OBJECTIVES: To evaluate the correlation of MRI and [(18)F]FDG-PET scans with the clinical course and inflammatory markers in patients with aortitis. METHODS: Eight patients with aortitis presenting with unspecific GCA-like symptoms were examined. Aortitis was diagnosed and followed up by [(18)F]FDG-PET and MRI. The aorta was divided into three vascular regions (ascending aorta, aortic arch, and descending aorta) to localise the aortic inflammation and compare both imaging techniques. RESULTS: were correlated with clinical and laboratory examinations. RESULTS: At diagnosis, 20/24 vascular regions from eight patients were positive by [(18)F]FDG-PET scan and 15/21 aortic regions by MRI. Patients were treated with corticosteroids and followed up for a mean (SD) of 13.3 (4.7) months. In [(18)F]FDG-PET, 11/20 (55%) initially pathological aortic regions returned to normal in the follow up examination, which correlated closely with the clinical and laboratory follow up examination. Conversely, in MRI, 14/15 initially affected vascular regions were unchanged. CONCLUSIONS: [(18)F]FDG-PET and MRI are both effective techniques for detecting early aortitis and have a high correlation with laboratory inflammatory measures. However, during the follow up examination, [(18)F]FDG-PET uptake decreased in line with the clinical symptoms and inflammatory serum markers, whereas MRI scans gave more static results.

Aged↗
PubMed2004

Quantitative thyroid scintigraphy for the differentiation of Graves' disease and hyperthyroid autoimmune thyroiditis.

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.

Diagnosis, Differential↗
PubMed2004

An in vitro study to compare 99mTc-stannous colloids and 99mTc-HMPAO for labelling human leukocytes.

AIM: Aim of the present study was to compare in vitro the labelling efficiency (LE) and cell viability (TBE) of autologous leukocytes labelled with (99m)Tc-SnF(2) and (99m)Tc-HMPAO, and to evaluate the quantity and quality of spontaneously released (99m)Tc (SR) from labelled cells at several time points after labelling. METHODS: A total of 14 patients with different diseases and 18 normal subjects were included in this study. A blood sample was collected from each patient; purified autologous leukocytes were divided into 2 samples and labelled with (99m)Tc-SnF(2) and (99m)Tc-HMPAO. LE was evaluated at the end of labelling and TBE and SR were evaluated at 10 min and 1 h, 2 h and 4 h after labelling. RESULTS: LE of (99m)Tc-SnF(2)-WBC was higher than (99m)Tc-HMPAO-WBC (61.2+/-18.7% and 43.3+/-11.3; p<0.0001) and we found an inverse correlation between blood glucose and labelling efficiency for both methods (p=0.02). Minimal differences were also observed between 2 methods after 10 min and 1 h, as far as the cell viability is concerned. The percentage of radioactivity spontaneously released from (99m)Tc-SnF(2)-WBC was significantly higher compared to (99m)Tc-HMPAO-WBC at each time point. Radioactivity released from labelled cells was predominantly (99m)Tc-SnF(2) and (99m)Tc-HMPAO with few free (99m)Tc (<20%). CONCLUSION: Both radiopharmaceuticals are not toxic for WBC. Labelling with (99m)Tc-SnF(2) give a higher LE than with (99m)Tc-HMPAO; however, radiolabelled colloids are more released from labelled cells over a period of 4 h. While (99m)Tc-HMPAO is physiological excreted into gastrointestinal tract, (99m)Tc-SnF(2) can be re-uptaken in vivo by reticulo-endothelial cells of liver and spleen. These findings suggest that (99m)Tc-SnF(2)-WBC might be better than (99m)Tc-HMPAO-WBC for studying inflammatory bowel diseases.

Cells, Cultured↗
PubMed2003

Early diagnosis and follow-up of aortitis with [(18)F]FDG PET and MRI.

The aim of this prospective study was to compare fluorine-18 fluorodeoxyglucose ([(18)F]FDG) positron emission tomography (PET) with magnetic resonance imaging (MRI) in patients with early aortitis, at the time of initial diagnosis and during immunosuppressive therapy. The study population consisted of 15 patients (nine females and six males; median age 62 years, range 26-76 years) who presented with fever of unknown origin or an elevated erythrocyte sedimentation rate or elevated C-reactive protein and who showed pathological aortic [(18)F]FDG uptake. Fourteen of these patients had features of early giant cell arteritis (GCA), while one had features of early Takayasu arteritis. During follow-up, seven PET scans were performed in six patients with GCA 4-30 months (median 19 months) after starting immunosuppressive medication. The results of [(18)F]FDG imaging were compared with the results of MRI at initial evaluation and during follow-up and with the clinical findings. At baseline, abnormal [(18)F]FDG uptake was present in 59/104 (56%) of the vascular regions studied in 15 patients. Seven follow-up PET studies were performed in six patients. Of 30 regions with initial pathological uptake in these patients, 24 (80%) showed normalisation of uptake during follow-up. Normalisation of [(18)F]FDG uptake correlated with clinical improvement and with normalisation of the laboratory findings. All except one of the patients with positive aortic [(18)F]FDG uptake were investigated with MRI and MRA. Thirteen of these 14 patients showed inflammation in at least one vascular region. Of 76 vascular regions studied, 41 (53%) showed vasculitis on MRI. Of 76 vascular regions studied with both PET and MRI, 47 were concordantly positive or negative on both modalities, 11 were positive on MRI only and 18 were positive on PET only. MRI was performed during follow-up in six patients: of 17 regions with inflammatory changes, 15 regions remained unchanged and two showed improvement. Whole-body [(18)F]FDG PET is valuable in the primary diagnosis of early aortitis. The results of [(18)F]FDG PET and MRI in the diagnosis of aortitis in this study were comparable, but FDG imaging identified more vascular regions involved in the inflammatory process than did MRI. In a limited number of patients [(18)F]FDG PET was more reliable than MRI in monitoring disease activity during immunosuppressive therapy.

Adult↗
PubMed2003

Dynamic lymphoscintigraphy and image fusion of SPECT and pelvic CT-scans allow mapping of aberrant pelvic sentinel lymph nodes in malignant melanoma.

To date, there are no reliable criteria to identify those patients with melanoma-infiltrated sentinel lymph nodes (SLNs) of the groin who might benefit from an extended lymphadenectomy, including the pelvic lymph nodes. We hypothesised that there are pelvic lymph nodes that receive lymph directly from the primary tumour, thus being at an increased risk for metastasis. In order to determine the frequency of radioactively labelled pelvic lymph nodes and the kinetics of their appearance, we introduce here a combination of dynamic lymphoscintigraphy, single photon emission computed tomography (SPECT) and image fusion of SPECT and pelvic Computed Tomography (CT)-scans. By dynamic lymphoscintigraphy and intraoperative gamma probe detection, superficially located inguinal SLNs (median 2 nodes) could be identified in all of the 51 patients included in this analysis. The histological search for micrometastases was positive in 16 patients (median Breslow thickness of the primary melanoma 2.5 mm). In 29 patients, SPECT and the image fusion technique were additionally performed. Radioactively labelled pelvic lymph nodes were detected in 20 individuals, 6 of them presenting aberrant pelvic SLNs that, on dynamic lymphoscintigraphy, had appeared simultaneously with the superficial SLN(s). Of the 6 patients in whom radioactive pelvic lymph nodes were excised together with the superficial SLN(s), only one had positive superficial SLNs. In this patient, the aberrant pelvic SLN proved to be tumour-positive. In 9 patients, there was no radiotracer uptake in the pelvic lymph nodes at all. Image fusion of SPECT and pelvic CT-scans is an excellent tool to localise exactly the pelvic tumour-draining nodes. The significance of radioactively labelled pelvic lymph nodes for the probability of pelvic metastases should be analysed further.

Adult↗
PubMed2003

[Clinical evaluation of a new thyroglobulin immunoradiometric assay in the follow-up of differentiated thyroid carcinoma].

AIM: Formal and clinical comparison of a new 3 (rd) -generation-Tg-IRMA (3-G-IRMA; Dynotest Tg-plus) with a conventional Tg-IRMA (3-G-IRMA; SELco Tg-assay) for patients with differentiated thyroid carcinoma. In addition we evaluated, if thyroglobulin (Tg) levels above a specific threshold concentration indicate the need for further investigations for residual disease. PATIENTS, METHODS: Tg concentration of 105 sera of 93 consecutive patients with a differentiated thyroid cancer was determined with both assays and compared at different cut-off values (Dynotest Tg-plus: 0.2, 1, 2 ng/ml; SELco Tg-assay: 0.5, 1, 2 ng/ml) with the clinical results in respect to the corresponding TSH concentration. RESULTS: Tg concentration did not show any significant difference (SELco Tg-assay 0.5 ng/ml, Dynotest Tg-plus 0.2 ng/ml). The Tg-values of both assays correlated with 97%. However, correlation of recovery in both assays was small (40%). The sensitivities and specificities of both assays at different cut-offs and TSH values did not reveal significant differences. In patients with TSH concentration > 30 micro U/ml the functional assay sensitivity was superior to arbitrary cut-offs in the decision to start further evaluations. CONCLUSIONS: In our study neither formal nor clinical significant differences between two Tg-assays were found. In a hypothyroid patient (TSH > 30 micro U/ml, Tg concentration exceeding the functional assay sensitivity) further investigations for residual disease are warranted. Higher thresholds are of limited value, due to an unacceptably high rate of false negative results.

Carcinoma↗
PubMed2002

Value of F-18 FDG hybrid camera PET and MRI in early takayasu aortitis.

Takayasu aortitis (TA) is a chronic inflammatory and fibrotic vasculitis of large- and medium-sized arteries. Early stages of the disease show a panarteritis and inflammatory wall thickening of the aorta and its branches, whereas advanced (fibrotic) stages comprise stenosis, aneurismatic transformation and occlusion. Magnetic resonance imaging visualises early-stage disease with high accuracy and is considered to be the method of choice in the diagnosis of TA. The aim of this article is the detailed comparison of FDG-PET performed with a hybrid camera and MR imaging in five patients with early TA. Five patients (median age 60 years) were enrolled during an ongoing prospective study on [18F]2'-deoxy-2-fluoro-D-glucose (FDG) hybrid camera PET in patients with fever of unknown origin (FUO). These patients underwent MR imaging after establishing the diagnosis of TA. Abnormal FDG uptake in the wall of the aorta was noted in all patients. The bracheocephalic artery and the common carotid arteries were visualized in 3 cases. Increased uptake of the subclavian artery was found in 3 patients and in 4 patients pathological uptake was noted in the ilio-femoral vessels. Of 34 vascular regions studied, 26 (76%) showed elevated FDG uptake. On transversal MR images vessel wall thickening and contrast enhancement of the thoracic aorta was found in 4 patients (ascending aorta/aortic arch: n=2; descending aorta: n=3; abdominal aorta: n=1). Additionally, vessel wall pathologies of the subclavian and the common carotid arteries could be shown in 1 patient and in another patient in the ilio-femoral arteries. No abnormalities were found using contrast-enhanced MR angiography. Of 28 vascular regions studied, 9 (32%) showed vasculitis on MRI. The FDG-PET is a suitable whole-body screening method in the primary diagnosis of early TA, especially in those cases with early disease that present with uncharacteristic symptoms such as FUO. Both MRI and MRA remain indispensable in the exact determination of the pathomorphological changes and in the documentation of complications such as stenosis, aneurismatic transformation and occlusion.

Aged↗
PubMed2002

The continuing importance of thyroid scintigraphy in the era of high-resolution ultrasound.

At the molecular level, the uptake of radioiodine and pertechnetate is proportional to the expression of the thyroidal sodium/iodine symporter (NIS). Qualitative and quantitative scintigraphic evaluation of the thyroid is performed with a gamma camera fitted with an on-line computer system and enables determination of the iodine uptake or the technetium uptake (TCTU) as an iodine clearance equivalent. Despite new molecular genetic insights into congenital hypothyroidism, the iodine-123 or pertechnetate scan remains the most accurate test for the detection of ectopic thyroid tissue. Following the identification of specific mutations of the genes coding for the NIS, thyroid peroxidase and pendrin, the discharge test has lost its role in establishing the diagnosis of inherited dyshormonogenesis, but it is still of value in the assessment of defect severity. In PDS mutations the test can be used to establish the diagnosis of syndromic disease. Quantitative pertechnetate scintigraphy is the most sensitive and specific technique for the diagnosis and quantification of thyroid autonomy. The method has proved to be valuable in risk stratification of spontaneous or iodine-induced hyperthyroidism, in the estimation of the target volume prior to radioiodine therapy and in the evaluation of therapeutic success after definitive treatment. In iodine deficiency areas the thyroid scan remains indispensable for the functional characterisation of a thyroid nodule and is still a first-line diagnostic procedure in cases of suspected thyroid malignancy. This is especially of importance in patients with Graves' disease, among whom a relatively high prevalence of cancer has been found in cold thyroid nodules. While determination of the TCTU is without any value in the differentiation between autoimmune thyroiditis and Graves' disease in most cases, it is of substantial importance in the differentiation between hyperthyroid autoimmune thyroiditis and Graves' disease.

Adult↗
PubMed2002

18F-FDG hybrid PET in patients with suspected spondylitis.

This study investigated the value of fluorine-18 2'-deoxy-2-fluoro- D-glucose (FDG) imaging with a double-headed gamma camera operated in coincidence (hybrid PET) detection mode in patients with suspected spondylitis. Comparison was made with conventional nuclear medicine imaging modalities and magnetic resonance imaging (MRI). Sixteen patients with suspected spondylitis (nine male, seven female, mean age 59 years) prospectively underwent FDG hybrid PET (296 MBq) and MRI. For intra-individual comparison, the patients were also imaged with technetium-99m methylene diphosphonate (MDP) (555 MBq) ( n=13) and/or gallium-67 citrate (185 MBq) ( n=11). For FDG hybrid PET, two or three transverse scans were performed. Ratios of infected (target) to non-infected (background) (T/B) vertebral bodies were calculated. MR images were obtained of the region of interest. Patients found positive for spondylitis with MRI and/or FDG hybrid PET underwent surgical intervention and histological grading of the individual infected foci. Twelve out of 16 patients were found to be positive for spondylitis. Independent of the grade of infection and the location in the spine, all known infected vertebrae ( n=23, 9 thoracic, 12 lumbar, 2 sacral) were detected by FDG hybrid PET. T/B ratios higher than 1.45+/-0.05 (at 1 h p.i.) were indicative of infectious disease, whereas ratios below this value were found in cases of degenerative change. FDG hybrid PET was superior to MRI in patients who had a history of surgery and suffered from a high-grade infection in combination with paravertebral abscess formation ( n=2; further computed tomography was needed) and in those with low-grade spondylitis ( n=2, no oedema) or discitis ( n=2, mild oedema). False-positive 67Ga citrate images ( n=5: 2 spondylodiscitis, 1 aortitis, 1 pleuritis, 1 pulmonary tuberculosis) and 99mTc-MDP SPET ( n=4: 1 osteoporosis, 2 spondylodiscitis, 1 fracture) were equally well detected by FDG hybrid PET and MRI. No diagnostic problems were seen in the other patients ( n=5). In this study, FDG hybrid PET was superior to MRI, 67Ga citrate and (99m)Tc-MDP, especially in patients with low-grade spondylitis (as compared with MRI), adjacent soft tissue infections (as compared with 67Ga citrate) and advanced bone degeneration (as compared with 99mTc-MDP).

Adult↗
PubMed2002

[F-18-FDG hybrid camera PET in patients with postoperative fever].

AIM: Evaluation of F-18-FDG-hybrid-camera-PET imaging in patients with undetermined postoperative fever (POF). METHODS: Prospective study of 18 patients (9 women, 9 men; age 23-85 years) suffering from POF with 2-fluoro-2'-deoxyglucose (F-18-FDG) using a dual headed coincidence camera (DHCC). Surgery had been performed 5-94 days prior to our investigation. 13 of the 18 patients received antibiotic therapy during the time of evaluation. Ten (55%) had an infectious and eight (45%) a non infectious cause of fever. RESULTS: Increased F-18-FDG-uptake outside the surgical wound occurred in 13 regions (infection n = 11, malignancy n = 2). The sensitivity of F-18-FDG-hybrid-camera-PET in imaging infection in areas outside the surgical wound was 86% and the specificity 100%, respectively. Antibiotic therapy did not negatively influence the results of F-18-FDG-scanning. Increased F-18-FDG-uptake within the surgical wound was seen in 8 of 18 patients. The sensitivity of F-18-FDG-hybrid-camera-PET in imaging infection within the surgical wound was 100% and the specificity 56%, respectively. The interval between surgery and F-18-FDG-scanning was significantly shorter in patients with false positive results compared with patients showing true negative results (median 34 vs. 54 days; p = 0.038). CONCLUSION: In POF-Patients, F-18-FDG transaxial tomography performed with a F-18-FDG-hybrid-camera-PET is sensitive in the diagnosis of inflammation and malignant disease within and outside the surgical wound. Because of the accumulation of the tracer both in granulation tissue and infection, the specificity in detecting the focus of fever within the surgical wound is poor.

Adult↗