Biomedical subjects

U Cremerius

Publications and source records attributed to U Cremerius.

42 records · Page 3Linked to original sources

PubMed1996

Imaging of beta-oxidation by static PET with 14(R,S)-[18F]-fluoro-6-thiaheptadecanoic acid (FTHA) in patients with advanced coronary heart disease: a comparison with 18FDG-PET and 99Tcm-MIBI SPET.

14(R,S)-[18F]-fluoro-6-thiaheptadecanoic acid (FTHA) has been proposed as a PET tracer of the beta-oxidation pathway. The aim of this study was to investigate the diagnostic value of FTHA using static PET imaging in patients with ischaemically reduced left ventricular function. Twenty-one patients with angiographically proven advanced coronary heart disease were examined. All patients underwent SPET with 400 MBq [99Tcm]-2-methoxy-isobutyl-isonitrile (MIBI) for perfusion assessment and PET with 250 MBq FTHA under fasting conditions and with 150 MBq 2-[18F]-fluoro-2-deoxyglucose (FDG) following an oral glucose load. The uptake of FTHA and FDG was analysed quantitatively in 33 regions. Regional uptake was normalized to the region with highest MIBI uptake and expressed as a percentage. FTHA uptake paralleled MIBI uptake (r = 0.80) but not FDG uptake (r = 0.57). Mean FTHA uptake (38.1 +/- 16.3%) in 190 regions with severely reduced perfusion (MIBI uptake < 50%, mean uptake 36.8 +/- 9.4%) was significantly lower compared to FDG uptake (54.6 +/- 25.0%). FTHA uptake was preserved (> or = 70%) in 8 of 52 (13%) regions only with severely reduced perfusion but preserved glucose metabolism (FDG uptake > or = 70%). The similarity between FTHA and MIBI uptake suggests that static PET imaging with FTHA is of limited value when distinguishing between ischaemic or hibernating myocardium and scar. The underestimation of viability may be caused both by the dependence of uptake on flow and the suppression of beta-oxidation in regional chronic ischaemia under fasting conditions.

Aged↗

PubMed1995

Monosomy 1p is correlated with enhanced in vivo glucose metabolism in meningiomas.

The 2-[18F]fluoro-2-deoxy-D-glucose (FDG) uptake of 25 human meningiomas was preoperatively evaluated in vivo by positron-emission tomography (PET). After surgery, meningioma biopsies were analyzed cytogenetically. Five meningiomas showed partial monosomy for chromosome 1p additional to other typical chromosome aberrations. This aberrant karyotype was correlated with increased FDG uptake. Three of five meningiomas with monosomy 1p were classified as grade II according to WHO, while only one of 20 tumors without monosomy 1p was classified as grade II. Thus, monosomy 1p and elevated FDG uptake in PET are to be regarded as cytogenetic and metabolic parameters for the aggressiveness of meningiomas.

Adult↗

PubMed1994

F-18 fluorodeoxyglucose PET in vivo evaluation of pancreatic glucose metabolism for detection of pancreatic cancer.

PURPOSE: To evaluate positron emission tomography (PET) with fluorine-18-labeled fluorodeoxyglucose (FDG) for detection of pancreatic cancer compared with computed tomography (CT) and ultrasonography (US). MATERIALS AND METHODS: Forty patients with suspected pancreatic cancer underwent static PET after intravenous injection of 150-300 MBq FDG. Focal FDG accumulation was regarded as a sign of malignancy and was quantitated by calculating differential uptake ratios (DURs) and tumor-liver ratios (TLRs). RESULTS: Malignancy was histologically proved in 27 patients. PET helped correctly classify 25 of 27 malignant conditions and 11 of 13 benign disorders. DUR and TLR were statistically significantly higher in malignant compared with benign disease (P < .01). False-negative findings were obtained in patients with insulin-dependent diabetes. False-positive findings were noted in a patient with retroperitoneal fibrosis and in one with pancreas divisum with chronic pancreatitis. PET was superior to CT and US in detection of lymph node metastases (13 of 17 vs three of 17 or one of 15, respectively. CONCLUSION: FDG PET has the potential to improve the detection of lymphadenopathy and the differential diagnosis of pancreatic masses.

Adenocarcinoma↗

PubMed1994

[18FDG-PET in intracranial meningiomas versus grading, proliferation index, cellular density and cytogenetic analysis].

62 intracranial meningiomas in 60 patients were studied with 18FDG-PET prior to neurosurgery in order to evaluate the relationship between 18FDG uptake and biological aggressiveness of the tumors. Histopathological grading, cellular density, Ki-67 proliferation index and evidence of chromosomal aberrations were used to assess tumor aggressiveness. Significantly elevated 18FDG uptake was found in grade 2- and 3- compared to grade 1-meningiomas, in tumors of high cellularity compared with those of low cellularity, and in meningiomas with an elevated Ki-67 proliferation index (above 2%). The two meningiomas with the most pronounced chromosomal aberrations revealed the highest 18FDG uptake of all cytogenetically studied meningiomas. We conclude that 18FDG-PET is useful for estimating the biological aggressiveness of intracranial meningiomas.

Adult↗

PubMedDate not supplied

[First experiences with fluorodeoxyglucose-positron-emission tomography (FDG-PET) in the evaluation of painful total knee and hip joint replacements].

AIM: The aim of the study was to describe first experiences using FDG-PET in the examination of painful arthroplasties. METHOD: 12 patients prior to revision of a total hip or knee joint replacement underwent PET. Histopathology, microbiological analysis and intraoperative diagnosis were compared to preoperative PET findings. RESULTS: The analysis of intraoperative findings, of microbiological examinations and of histopathology showed that besides the well known determinants infection and early postoperative granulation tissue, polyethylene wear induced foreign-body reaction was a major cause for increased FDG consumption. CONCLUSION: In vivo imaging of marked foreign-body tissue reaction induced by polyethylene wear is feasible by FDG-PET. This observation, however, leads to reduced specificity of PET imaging for the diagnosis of periprosthetic infection.

Aged↗

PubMedDate not supplied

[[F-18]-fluorodeoxyglucose (FDG) positron emission tomography (PET) as a diagnostic for hip endoprosthesis loosening].

AIM: The purpose of this study was to examine the FDG-PET in respect of its diagnostic valency with regard to septic/aseptic loosening of lower limb prostheses. METHOD: 28 patients with 41 lower limb prostheses were examined by means of FDG-PET to evaluate septic/aseptic loosening of their hip prostheses. Therefore, a differentiated FDG-PET result interpretation subdivided into five categories was developed. The final diagnosis was based on operative findings with following culture and histological outcome. RESULTS: The worked-out categories showed a high agreement to the intraoperative macroscopic and histological results (n = 23 correctly positive, n = 1 false positive, n = 1 correctly negative and n = 3 false negative). CONCLUSION: With a subtly differentiated interpretation (categories I - V) of the qualitative glucose metabolism safe statements can be made regarding septic/aseptic endoprostheses loosening. This was impressively confirmed by the agreement of the FDG results with the histological results.

Aged↗