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Biomedical subjects

U Cremerius

Publications and source records attributed to U Cremerius.

At least 19 recordsLinked to original sources
PubMed2005

Radionuclide imaging of the painful hip arthroplasty: positron-emission tomography versus triple-phase bone scanning.

Two major complications of hip replacement are loosening and infection. Reliable differentiation between these pathological processes is difficult since both may be accompanied by similar symptoms. Our aim was to assess the diagnostic ability of triple-phase bone scanning (TPBS) and positron-emission tomography (PET) to detect and differentiate these complications in patients with a hip arthroplasty. Both TPBS and PET were performed in 63 patients (92 prostheses). The radiotracer for PET imaging was (18)F-fluorodeoxyglucose (FDG). Image interpretation was performed according to qualitative and quantitative criteria although the final diagnosis was based upon either surgical findings or clinical follow-up. The sensitivity, specificity and accuracy of PET was 0.94, 0.95 and 0.95 respectively, compared with 0.68, 0.76 and 0.74 for TPBS. We found that an image interpretation based exclusively upon quantitative criteria was inappropriate because of its low selectivity. The histological examination indicated that increased periprosthetic uptake of FDG in patients with aseptic loosening was caused by wear-induced polyethylene particles and the subsequent growth of aggressive granulomatous tissue.

Adult↗
PubMed2003

[FDG PET as an early nuclear medical diagnostic tool for aseptic wear-induced loosening of hip joint endoprostheses--a report of two cases].

To date, 2-[F-18]fluoro-2-deoxy-D-glucose PET (FDG PET) is used as a tool in oncology as well as myocardiological and cerebral functional diagnostics in the clinical routine. False positive results of tumor search imply new possibilities for use in diagnostics of inflammation. The two case reports presented here on aseptic loosening of endoprostheses caused by the rub of polyethylene with histological and immunohistological refurbishing call attention to the possible diagnostic valency of FDG PET as an early warning system regarding aseptic artificial limb loosening induced by the rub of polyethylene. By quantification of glucose metabolism with the "standard uptake value" (SUV) as well as specific storage samples from around the artificial limb, it is the aim of our study group in further examinations to develop an algorithm which permits to distinguish between septic and aseptic loosening.

Acetabulum↗
PubMed2003

Fluordeoxyglucose positron emission tomography detection of inflammatory reactions due to polyethylene wear in total hip arthroplasty.

A patient experienced chronic pain 8 years after total hip arthroplasty. Radiology and bone scanning showed no signs of aseptic loosening, but fluorine-18 fluorodeoxyglucose positron-emission tomography ((18)F-FDG-PET) showed intensive glucose metabolism in the joint capsule and around the prosthesis neck. The surgical intervention revealed soft tissue reaction in this area. Histologic examination showed a granulomatous foreign body reaction against polyethylene debris particles. Infection and rheumatoid arthritis could be excluded clinically, histologically, microbiologically, and with the bone scan. Therefore, FDG-PET detected inflammatory reaction caused by polyethylene wear in total hip arthroplasty and allowed clinicians to decide on interventions, including removal of granulomatous tissue and the replacement of worn artificial joint components to prevent aseptic loosening.

Fluorodeoxyglucose F18↗
PubMed2003

[Analysis of (18)F-FDG uptake patterns in PET for diagnosis of septic and aseptic loosening after total hip arthroplasty].

AIM: Identification of typical patterns for fluorodeoxy-glucose (FDG) uptake in positron emission tomography (PET) to detect aseptic loosening of hip prosthesis (ace-tabular and/or femoral component) and prosthetic infection. METHODS: 18 patients with painful hip prosthesis underwent PET using a dedicated full ring scanner after application of 200-300 MBq FDG. The interface between bone and surrounding soft tissue or bone as displayed on coronal slices was divided into 12 segments in accordance with the classifications of Delee and Gruen. FDG uptake in each of the segments was scored (0-3) by two independent observers. Intraoperative findings were regarded as the gold standard. RESULTS: After surgical revision 14 acetabular components and 9 femoral components were found to be loose and prosthetic infection was present in 7 prostheses. Loosening of the acetabular component was correlated to enhanced uptake in the middle of the acetabular interface, while loosening of the femoral component was correlated to enhanced uptake in the proximal and middle segment of the lateral femoral interface and the proximal segment of the medial femoral interface. A similar pattern was found in prosthetic infection with high uptake along the middle portion of the lateral femoral interface. In 6 of 7 infected prostheses loosening of the acetabular and of the femoral component was present. Taking the typical uptake patterns as criteria for loosening and grade 3 uptake as an additional criterion for septic loosening the accuracy of PET imaging in the detection of loosening of the acetabular or the femoral component and of prosthetic infection was 72, 78 and 89%, respectively. CONCLUSION: This pilot study presents FDG-PET as a promising diagnostic tool for patients with painful hip prostheses. Its clinical value should be evaluated in a larger patient population.

Aged↗
PubMed2002

Pre-transplant positron emission tomography (PET) using fluorine-18-fluoro-deoxyglucose (FDG) predicts outcome in patients treated with high-dose chemotherapy and autologous stem cell transplantation for non-Hodgkin's lymphoma.

We investigated the predictive value of sequential FDG PET before and after high-dose chemotherapy (HDT) and autologous stem cell transplantation (ASCT) in 24 patients suffering from non-Hodgkin's lymphoma (NHL). FDG PET was performed at baseline, after three cycles of induction therapy, before and after HDT with ASCT. Response assessment from sequential PET scans using standardized uptake values (SUV) was available in 22 patients at the time of transplantation. Partial metabolic response (PMR) was defined as a >25% decrease of SUV between successive PET scans [corrected]. Six of seven patients who did not achieve a PMR after complete induction therapy developed lymphoma progression, while 10 of 15 patients with complete metabolic response (CMR) or PMR remained in continuous remission. Four of seven patients with less than PMR after induction therapy died vs two of 15 patients with CMR/PMR. Median progression-free and overall survival of patients with less than PMR after HDT and ASCT was 9 and 29 months, respectively. In contrast, neither conventional re-staging nor the International Prognostic Index were predictive. These data suggest that sequential quantitative PET imaging does enlarge the concept of chemosensitivity used to select patients with high-risk NHL for HDT and ASCT or to route them to alternative treatments.

Adult↗
PubMed2002

Combined image interpretation of computed tomography and hybrid PET in head and neck cancer.

AIM: Evaluation of potential synergistic effects of combined image interpretation of FDG PET using a gamma camera modified for coincidence detection (hybrid PET) and computed tomography (CT) and comparison of the diagnostic accuracy of hybrid PET and dedicated PET in patients with head and neck cancer. METHODS: Forty-two patients with suspected primary or recurrent cancer were included. Twenty-four patients underwent dedicated PET in addition to attenuation-corrected hybrid PET using a one-day protocol. RESULTS: Sensitivity, specificity and accuracy for detection of primary or recurrent head and neck cancer were 74, 73, and 74% for hybrid PET, 52, 82, and 60% for CT and 77, 82, and 79% for combined reading. With the combination of CT and hybrid PET all cases of recurrent disease were detected. The largest tumour not detected was 1.7 cm in diameter. Sensitivity, specificity and accuracy for the detection of neck sides with lymph node metastases were 69, 88, and 85% for hybrid PET, 62, 88, and 84% for CT, 69, 99, and 94% for combined image interpretation. With combined interpretation four involved neck sides were missed including two cases of microscopic metastases. Hybrid PET revealed concordant results to dedicated PET in all patients with respect to the detection of primary or recurrent tumour and in 45 of 48 neck sides (94%) with the same number of false negative findings. CONCLUSION: The combination of functional information of hybrid PET and morphological information of CT by the simple approach of combined image interpretation improves the sensitivity for the detection of primary/recurrent head and neck cancer and increases the specificity of lymph node staging compared to CT alone. The accuracy of hybrid PET and dedicated PET was almost identical.

Carcinoma, Squamous Cell↗
PubMed2001

Analysis of FDG uptake with hybrid PET using standardised uptake values.

The standardised uptake value (SUV) has been used as an index of glucose metabolism to classify malignant tumours. To date, calculation of SUVs has been restricted to dedicated PET. The aim of this study was to investigate the feasibility of SUV calculation with attenuation-corrected hybrid PET, applying a singles count rate-related calibration method. Calibration factors for hybrid PET at different singles count rates were determined by phantom studies. SUVs were determined for hot spheres in a phantom study as well as for 68 malignant lesions in 56 patients. Recovery coefficients calculated for hot spheres were applied to SUVs of malignant lesions to correct for partial volume and recovery effects. At a sphere-to-background ratio of 10:1, SUVs of spheres with diameters from 34 to 16 mm varied from 5.0 to 1.5 for hybrid PET, and from 8.0 to 4.3 for dedicated PET. SUVs of malignant lesions calculated by hybrid and dedicated PET showed a strong correlation (r=0.95, P<0.001), with a mean percentage difference of 36%. SUVs calculated by hybrid PET were significantly lower than SUVs calculated by dedicated PET (6.2+/-4.3 vs 8.5+/-5.3, P<0.001). Application of recovery coefficients revealed an SUV of 12.2+/-7.3 for hybrid PET versus 10.8+/-6.3 for dedicated PET, with a significant reduction in the mean percentage difference (22%, P<0.01). In conclusion, singles count rate-related calibration factors allow calculation of SUVs with hybrid PET for lesions with a diameter larger than 15 mm. Correction for partial volume and recovery effects is needed to improve the agreement of SUVs of lesions determined by hybrid PET and dedicated PET.

Calibration↗
PubMed2001

Optimizing ventilation-perfusion lung scintigraphy: parting with planar imaging.

AIM: Of the study was to introduce and verify a ventilation-perfusion (V/Q) acquisition protocol that incorporates new developments in scintigraphy in order to allow for a more balanced comparison with other diagnostic procedures. METHODS: In 103 patients suspect of having pulmonary embolism, V/Q scans were acquired exclusively with SPECT technique. Ventilation was done with ultrafine aerosol. Planar images in eight directions were reconstructed through addition of three consecutive SPECT projections. Three referees examined the scans in regard to type, localization, and extent of V/Q defects. RESULTS: Using this protocol, significantly more defects, especially of subsegmental size, were detected (p < 0.01). Sensitivity, and diagnostic accuracy were also significantly improved (p < 0.01) to 0.96, and 0.99, respectively. Furthermore, kappa values were increased up to 0.82--a relevant enhancement in the ability to precisely localize V/Q defects. CONCLUSION: In conclusion this protocol provides high-resolution tomographic scans as well as high-quality planar images within a short acquisition time. Due to the significant increase in lesion detection, sensitivity, diagnostic accuracy, and anatomical localization of defects, it is a substantial improvement in the diagnosis of pulmonary embolism that will put V/Q scintigraphy on a par with other tomographic methods.

Adolescent↗
PubMed2001

Prognostic significance of positron emission tomography using fluorine-18-fluorodeoxyglucose in patients treated for malignant lymphoma.

AIM: To evaluate the prognostic significance of positron emission tomography (PET) using fluorine-18-[2]-fluoro-2-deoxyglucose (FDG) in patients treated for Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL) compared to conventional restaging (CRS). METHODS: Fifty-six patients with either HD (n = 22), high-grade NHL (n = 26) or centrocytic-centroblastic NHL (n = 8) were included. PET was performed in 41 patients for treatment reevaluation up to three months after therapy and in patients with persisting residual masses (n = 10) or suspected relapse (n = 5) four to twelve months after treatment. The scans were evaluated qualitatively and quantitatively using standardised uptake values (SUV). Progression-free survival (PFS) was estimated to assess the prognostic value of FDG PET and clinical follow-up was taken as gold standard. RESULTS: PET was positive in nineteen of 41 patients studied for treatment reevaluation. Progression was observed after a median interval of two months (range 0-15) in sixteen of 19 patients after a positive PET scan and in three of 22 patients after a negative scan (p < .001). Median duration of follow-up in progression-free patients was 21 months (range 6-72). In patients with a partial remission in CRS progression was more common in PET-positive than in PET-negative patients (5 of 7 vs. 1 of 14; p < .01) and positivity with PET was associated with poorer PFS (p < .0025). PET studies performed four to twelve months after treatment were true negative in seven, true positive in five and false-positive in three patients. SUV > 11.35 of lymphoma lesions was associated with poorer PFS than SUV < 11.35 (p < 0.025). CONCLUSION: We conclude that FDG PET after treatment of malignant lymphoma has a high prognostic value and should be recommended in patients with persistence of residual masses.

Adolescent↗
PubMed2000

Benign versus malignant osseous lesions in the lumbar vertebrae: differentiation by means of bone SPET.

Bone scanning is a well-accepted and frequently performed diagnostic procedure with a high sensitivity, especially when single-photon emission tomography (SPET) acquisitions are added. However, the differentiation of benign from malignant osseous lesions often poses difficulty. The purpose of this study was to find out whether the particular localisation of an intraosseous lesion in a lumbar vertebra is an indicator of its aetiology. Bone scintigraphy including planar whole-body scans as well as SPET imaging of the lumbar spine was performed in 109 patients. The diagnoses of osseous lesions in the lumbar vertebrae were made strictly on the basis of the findings of magnetic resonance imaging, computed tomography or plain radiography. Sixteen patients had to be excluded from the study because they did not undergo adequate radiological examination. To determine the particular localisation of vertebral lesions in the bone scan, two experienced nuclear medicine physicians examined the studies independently while blinded to the radiological results. Four anatomical regions were differentiated within the vertebra: the vertebral body, the pedicle, the facet joints and the spinous process. Clopper-Pearson analysis, which takes into account the number of examinations, yielded the following probability intervals for the malignancy of intraosseous lesions in the lumbar spine: vertebral body 36.8%-57.3%, pedicle 87.7%-100%, facet joints 0.8%-21.4% and spinous process 18.7%-81.3%. It was concluded that lesions affecting the pedicle are a strong indicator for malignancy, whereas involvement of the facet joints is usually related to benign disease. Lesions affecting the vertebral body or the spinous process do not show a clear tendency towards either malignancy or benignity. In contrast to other studies, a significant probability of malignancy (35.6%) was observed in lesions affecting exclusively the vertebral body.

Adult↗
PubMed2000

[Results of pretherapeutic lymph node diagnosis in head and neck tumors. Clinical value of 18-FDG positron emission tomography (PET)].

BACKGROUND: Histological studies demonstrate that there is a high percentage of occult nodal metastasis in head and neck malignomas. Patients with positive lymph nodes have a comparatively worse prognosis. A neck dissection is required in these cases. By demonstrating morphological abnormalities, imaging procedures like ultrasound, computer tomography (CT), and magnetic resonance imaging (MRI) can provide important initial informations about possible malignant alteration of the lymph nodes. Positron emission tomography (PET) allows functional metabolic imaging of a suspected tumor site. The aim of this study was a comparative evaluation of different diagnostic procedures with special emphasis on the value of PET in the pretherapeutic diagnosis of nodal spread in head and neck cancer. PATIENTS AND METHODS: Forty patients (28 male and 12 female) with a suspected malignoma in the head and neck region underwent clinical examination including palpation of the neck sides, ultrasound, CT, and PET to detect a nodal spread of the malignancy. Fifty neck dissections were performed in 28 patients. Lymph node biopsies were performed in the remaining patients. The results of the diagnostic procedures were compared to the histology and the clinical course of the patients. The mean follow-up period was 12.5 months. RESULTS: A nodal metastasis was verified in 35% of all cases. Sensitivity of all imaging procedures including PET was 82%. Palpation had a sensitivity of only 61%. Specificity was 85% for ultrasound, 94% for CT and palpation, and 87% for PET. PET produced false negative results in 13.4% of all cases. Inflammation was detected in these cases. The positive predictive value was marginally better for PET than for ultrasound (77% vs. 75%). It proved to be lower than the values for palpation (86%) and CT (88%). Negative predictive value was 90-91% for all imaging procedures. CONCLUSION: In the primary diagnosis of nodal alterations in the head and neck region, a PET scan has the same diagnostic value as ultrasound or CT. By imaging the metabolism of a suspected nodal metastasis, PET can help to improve the assessment of regions with uncertain anatomic features. To avoid false positive results, acute and chronic inflammatory alterations have to be ruled out before the PET imaging.

Aged↗
PubMed2000

Fluorodeoxyglucose positron emission tomography and the prognosis of pancreatic carcinoma.

BACKGROUND: Pancreatic carcinoma is associated with a poor prognosis. The aim of this study was to determine whether glucose metabolism in pancreatic cancer has prognostic significance for patients suffering from this disease. METHODS: The survival data of 52 patients with pancreatic carcinoma was correlated with the standardized uptake value (SUV) as a semiquantitative parameter of glucose metabolism, as determined with fluorodeoxyglucose positron emission tomography (FDG PET). A multivariate analysis, including SUV and accepted factors of prognosis, such as stage at presentation and tumor marker Ca 19-9, was performed to determine the prognostic value of FDG PET. RESULTS: The median survival in 26 patients with low SUV (< 6.1) was 9 months (95% confidence interval 6-12 months) vs. 5 months (95% confidence interval 4-6 months) in 26 patients with high SUV (> or = 6.1). Multivariate analysis revealed SUV and tumor marker Ca 19-9 as independent factors of prognosis in patients with pancreatic carcinoma. CONCLUSION: Glucose metabolism, as determined with FDG PET, provides additional prognostic information in patients with pancreatic carcinoma.

Adenocarcinoma↗
PubMed1999

Dual-head gamma camera 2-[fluorine-18]-fluoro-2-deoxy-D-glucose positron emission tomography in oncological patients: effects of non-uniform attenuation correction on lesion detection.

The purpose of this study was to evaluate a dual head coincidence gamma camera (DH-PET) equipped with single-photon transmission for 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) imaging in oncological patients. Forty-five patients with known or suspected malignancies, scheduled for a positron emission tomography (PET) scan, were first studied with a dedicated ring PET and subsequently with DH-PET. All patients underwent measured attenuation correction using germanium-68 rod sources for ring PET and caesium-137 sources for DH-PET. Ring PET emission scan was started 64+/-17 min after intravenous administration of 235+/-42 MBq FDG. DH-PET emission followed 160+/-32 min after i.v. FDG. Attenuation-corrected and non-attenuation-corrected images were reconstructed for ring PET and DH-PET. The image sets were evaluated independently by three observers blinded to clinical data and to results of conventional imaging. Attenuation-corrected ring PET as the standard of reference depicted 118 lesions, non-attenuation-corrected ring PET 113 (96%) lesions, and attenuation-corrected DH-PET and non-attenuation-corrected DH-PET, 101 (86%) and 84 (71%) lesions, respectively (P<0.05). The lesion detection rate of attenuation-corrected and non-attenuation-corrected DH-PET was almost similar for lesions >20 mm, whereas attenuation correction increased the detection rate from 60% to 80% for lesions </=20 mm (P<0.01). A patient-based analysis revealed concordant results relative to attenuation-corrected ring PET for non-attenuation-corrected ring PET, attenuation-corrected DH-PET and non-attenuation-corrected DH-PET in 42 (93%), 36 (80%) and 31 (69%) patients, respectively. Differences might have influenced patient management in two (4%), six (13%) and ten (22%) patients, respectively. In conclusion, measured attenuation correction markedly improves the lesion detection capability of DH-PET. With measured attenuation correction the diagnostic performance of DH-PET is closer to that of dedicated ring PET.

Evaluation Studies as Topic↗
PubMed1999

Fluorine-18 fluorodeoxyglucose positron emission tomography in thyroid cancer: results of a multicentre study.

The aim of this multicentre study was to evaluate the clinical significance of fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in differentiated thyroid carcinoma and to compare the results with both iodine-131 whole-body scintigraphy (WBS) and technetium-99m 2-methoxyisobutylisonitrile (MIBI) or thallium-201 chloride (Tl) scintigraphy. Whole-body PET imaging using FDG was performed in 222 patients: 134 with papillary tumours, 80 with follicular tumours and 8 with mixed-cell type tumours. Finally, for each case an overall clinical evaluation was done including histology, cytology, thyroglobulin level, ultrasonography, computed tomography and subsequent clinical course, to allow a comparison with functional imaging results. Sensitivity of FDG-PET was 75% and 85% for the whole patient group (n = 222) and the group with negative radioiodine scan (n = 166), respectively. Specificity was 90% in the whole patient group. Sensitivity and specificity of WBS were 50% and 99%, respectively. When the results of FDG-PET and WBS were considered in combination, tumour tissue was missed in only 7%. Sensitivity and specificity of MIBI/Tl were 53% and 92%, respectively (n = 117). We conclude that FDG-PET is a sensitive method in the follow-up of thyroid cancer which should be considered in all patients suffering from differentiated thyroid cancer with suspected recurrence and/or metastases, and particularly in those with elevated thyroglobulin values and negative WBS.

Female↗
PubMed1999

Does positron emission tomography using 18-fluoro-2-deoxyglucose improve clinical staging of testicular cancer?--Results of a study in 50 patients.

OBJECTIVES: To compare positron emission tomography (PET) using 18-fluoro-2-deoxyglucose (FDG) with conventional clinical staging in unselected patients with germ cell cancer. METHODS: Fifty patients underwent PET scans of the abdomen (n = 50) and chest (n = 41 ) after the initial diagnosis. PET images were evaluated qualitatively and quantitatively using standardized uptake values (SUVs). The results were compared with computed tomography (CT) results and tumor markers (human chorionic gonadotropin, alpha-fetoprotein, and lactate dehydrogenase). Retroperitoneal lymphadenectomy in 12 patients and clinical staging, including follow-up data in all patients, were taken as a reference standard. RESULTS: PET detected metastases in 13 (87%) of 15 patients and excluded metastases in 33 (94%) of 35 patients. A sensitivity of 73% and a specificity of 94% were obtained using CT. The respective values for tumor marker determination were 67% and 100%. Retroperitoneal metastases were detected in 2 patients by PET only and in 1 patient by CT only. In the latter patient, surgery of a residual mass after chemotherapy revealed a well-differentiated teratoma. False-negative findings with PET and CT occurred in 2 patients with retroperitoneal metastases approximately 10 mm in size. False-positive findings were due to sarcoidosis or to muscular activity of the neck. Quantitative FDG uptake was very heterogeneous, with an SUV ranging from 1.8 to 17.3. CONCLUSIONS: FDG PET has the potential to improve clinical staging of testicular cancer. However, PET, as well as CT, is limited in the detection of small retroperitoneal lymph node metastases.

Adult↗
PubMed1999

Measurement of clinical and subclinical tumour response using [18F]-fluorodeoxyglucose and positron emission tomography: review and 1999 EORTC recommendations. European Organization for Research and Treatment of Cancer (EORTC) PET Study Group.

[18F]-fluorodeoxyglucose ([18F]-FDG) uptake is enhanced in most malignant tumours which in turn can be measured using positron emission tomography (PET). A number of small clinical trials have indicated that quantification of the change in tumour [18F]-FDG uptake may provide an early, sensitive, pharmacodynamic marker of the tumoricidal effect of anticancer drugs. This may allow for the introduction of subclinical response for anticancer drug evaluation in early clinical trials and improvements in patient management. For comparison of results from smaller clinical trials and larger-scale multicentre trials a consensus is desirable for: (i) common measurement criteria; and (ii) reporting of alterations in [18F]-FDG uptake with treatment. This paper summarises the current status of the technique and recommendations on the measurement of [18F]-FDG uptake for tumour response monitoring from a consensus meeting of the European Organization for Research and Treatment of Cancer (EORTC) PET study group held in Brussels in February 1998 and confirmed at a subsequent meeting in March 1999.

Antineoplastic Agents↗
PubMed1999

F-18-FDG positron imaging in oncological patients: gamma camera coincidence detection versus dedicated PET.

AIM: Of the present study was to investigate the feasibility of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) imaging in oncological patients with a dual head gamma camera modified for coincidence detection (MCD). METHODS: Phantom studies were done to determine lesion detection at various lesion-to-background ratios, system sensitivity and spatial resolution. Thirty-two patients with suspected or known malignant disease were first studied with a dedicated full-ring PET system (DPET) applying measured attenuation correction and subsequently with an MCD system without attenuation correction. MCD images were first interpreted without knowledge of the DPET findings. In a second reading, MCD and DPET were evaluated simultaneously. RESULTS: The phantom studies revealed a comparable spatial resolution for DPET and MCD (5.9 x 6.3 x 4.2 mm vs. 5.9 x 6.5 x 6.0 mm). System sensitivity of MCD was less compared to DPET (91 cps/Bq/ml/cmFOV vs. 231 cps/Bq/ml/cmFOV). At a lesion-to-background ratio of 4:1, DPET depicted a minimal phantom lesion of 1.0 cm in diameter, MCD a minimal lesion of 1.6 cm. With DPET, a total of 91 lesions in 27 patients were classified as malignant. MCD without knowledge of DPET results revealed increased FDG uptake in all patients with positive DPET findings. MCD detected 72 out of 91 DPET lesions (79.1%). With knowledge of the DPET findings, 11 additional lesions were detected (+12%). MCD missed lesions in six patients with relevance for staging in two patients. All lesions with a diameter above 18 mm were detected. CONCLUSION: MCD FDG imaging yielded results comparable to dedicated PET in most patients. However, a considerable number of small lesions clearly detectable with DPET were not detected by MCD alone. Therefore, MCD cannot yet replace dedicated PET in all oncological FDG studies. Further technical refinement of this new method is needed to improve image quality (e.g. attenuation correction).

Adult↗