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Ur Metser

Publications and source records attributed to Ur Metser.

27 records · Page 2Linked to original sources
PubMed2004

Malignant involvement of the spine: assessment by 18F-FDG PET/CT.

UNLABELLED: The purpose of the study was to assess the role of (18)F-FDG PET/CT in the assessment of secondary malignant involvement of the spinal column. METHODS: In 51 patients, 242 lesions at the spinal region detected on (18)F-FDG PET/CT were interpreted separately on PET, CT, and fused PET/CT images, including differentiation between benign and malignant lesions and the level in the vertebral column. CT evaluation also included the type of bony lesion (osteolytic, osteoblastic, or mixed) and accompanying soft-tissue abnormalities; for example, epidural masses and tumor involvement of the neural foramina. RESULTS: Of the 242 lesions detected on PET/CT, PET alone identified 220 lesions and CT alone identified 159; 217 (90%) were malignant and 25 benign. (18)F-FDG PET alone detected significantly more malignant lesions than did CT alone (96% vs. 68%, respectively, P < 0.001). The specificity was 56% for both PET alone and CT alone. PET alone was incorrect in determining the level of abnormality within the vertebral column in 33 (15%) lesions and in determining the part of the vertebra involved in 40 (18%) lesions. In 17 (33%) patients, either epidural extension of tumor (n = 7 lesions), neural foramen involvement of tumor (n = 7 lesions), or a combination of both (n = 11 lesions) was detected. On a patient-based analysis, the sensitivity of PET and of PET/CT for the detection of spinal metastasis was 98% and 74%, respectively (P < 0.01). CONCLUSION: (18)F-FDG PET/CT has better specificity for detection of malignant involvement of the spine than does (18)F-FDG PET. It allows for precise localization of lesions and identifies accompanying soft-tissue involvement, which is of potential neurologic significance.

Female↗
PubMed2003

Diagnosis and treatment of breast fibroadenomas by ultrasound-guided vacuum-assisted biopsy.

HYPOTHESIS: Ultrasound-guided vacuum-assisted biopsy (UGVAB) can serve as an efficient tool for the diagnosis and excision of breast fibroadenomas. DESIGN: Patients with a clinically and radiographically suspected breast fibroadenoma were prospectively referred for UGVAB to confirm the diagnosis and to attempt to excise the lesion. PATIENTS: Fifty-two female patients, aged 19 to 68 years, were included in the 2-year study. All had at least 1 suspected fibroadenoma. The procedure was performed for a total of 56 lesions. INTERVENTIONS: Imaging modalities prior to biopsy to confirm the clinical suspicion included Doppler ultrasound and mammography or Doppler ultrasound alone. Tumor size and volume were recorded. Ultrasound-guided vacuum-assisted biopsy was performed in all cases, with guidance using the 11-gauge Mammotome handheld vacuum-assisted biopsy system (Ethicon Endo-Surgery Inc, Cincinnati, Ohio). MAIN OUTCOME MEASURES: Major end points included diagnosis compatibility rate, excision rate, complications, and short-term follow-up. RESULTS: A tissue diagnosis was obtained in all cases and was compatible with the clinical diagnosis of fibroadenoma. Complete excision was achieved in all lesions less than or equal to 1.5 cm (mean volume, 0.25 mL). All lesions greater than 2 cm (mean volume, 1 mL) were incompletely excised. Of the 20 lesions measuring 1.5 to 2.0 cm, 11 (55%) were completely excised. The volume of all completely excised lesions was less than 0.9 mL. Four lesions with a volume less than 0.9 mL were incompletely excised due to bleeding. Ten of the 13 cases with incomplete excision were confident enough with the diagnosis to choose imaging follow-up instead of surgery. Two patients (16%) were referred by the radiologist for surgical excision. Only 1 patient with incomplete removal (8%) felt uncomfortable with the remnant lump and requested surgical excision. CONCLUSIONS: Although the breast fibroadenoma is a common benign breast tumor, the treatment and follow-up of these lesions is still debatable. We suggest that UGVAB, which has a well-documented role in the diagnosis of breast lesions, may provide an option for the definitive treatment of breast fibroadenomas.

Adult↗
PubMed2003

Hilar biliary obstruction: preliminary results with Levovist-enhanced sonography.

OBJECTIVE: The aim of this study was to investigate the value of using Levovist in the postvascular phase of sonography performed to assess hepatic hilar biliary obstruction. SUBJECTS AND METHODS: In our prospective study, 50 patients underwent routine sonography followed by postvascular Levovist-enhanced pulse inversion imaging of the liver. Thirty-six patients had malignant disease (28 invasive parenchymal tumors and eight intraductal tumors), and 14 had benign disease. The 36 malignancies included 29 cholangiocarcinomas, six invasive gallbladder carcinomas, and one colon metastasis. Fourteen patients had benign disease: benign strictures (n = 5), primary sclerosing cholangitis (n = 5), chronic Mirizzi's syndrome (n = 1), varicosities of the parabiliary venous plexus (n = 1), and inflammatory liver lesions (n = 2). Sonographic findings in all 50 patients were correlated with findings from other imaging modalities (n = 50) as well as surgical specimens (n = 20), core biopsies (n = 3), and both clinical and imaging follow-ups (n = 24). RESULTS: Seventeen (61%) of the 28 invasive intraparenchymal malignancies were visualized on routine sonograms, whereas all 28 (100%) were visualized on enhanced sonograms (p < 0.01). In 15 (88%) of 17 patients in whom tumor was seen on routine sonograms, contrast-enhanced sonography showed further mass extent, increased conspicuity, or satellite nodules not visualized on the baseline image. All eight noninvasive intraductal malignancies were correctly identified and staged on the routine sonography. In one of these patients, hepatic invasion was prospectively overcalled on the enhanced image. Of the 14 benign lesions, three had inflammatory periductal abnormalities seen exclusively or to advantage on the enhanced study. Correct prediction of resectability in the 16 patients with malignant disease who underwent surgery improved from 11 (69%) of 16 on unenhanced sonography to 15 (94%) of 16 on enhanced sonography (p = 0.13). CONCLUSION: Detection and staging of malignant hilar obstructions are improved by the use of Levovist in the postvascular phase of sonography compared with routine sonography.

Adult↗
PubMed2003

MR imaging findings and patterns of spread in secondary tumor involvement of the uterine body and cervix.

OBJECTIVE: Our study sought to describe the MR imaging features and the patterns of spread in secondary tumor involvement of the uterus by nonuterine tumors. CONCLUSION: Direct extension of an adjacent tumor to the uterus is the most common pattern of secondary tumor involvement. Concomitant invasion of other pelvic organs is also typical. Although less common, hematogenous or lymphatic metastases to the uterus are encountered in clinical practice. Metastases should be added to the differential diagnosis of apparently malignant masses in the uterine body or cervix, especially in patients with metastatic disease or in patients whose uterus shows a preserved shape with involvement by an infiltrative heterogeneously enhancing process.

Adolescent↗
PubMedDate not supplied

Role of 18F-FDG PET/CT in staging and follow-up of lymphoma in pediatric and young adult patients.

OBJECTIVE: To assess the role of 18F-Fluorodeoxyglucose (18F-FDG) PET/CT in pediatric patients with Hodgkin disease (HD) and non-Hodgkin lymphoma (NHL). MATERIALS AND METHODS: 31 patients, mean age 12.9 +/- 5.1, HD (n = 24), and NHL (n = 7) underwent 18F-FDG PET/CT at diagnosis (n = 31 studies) and later in the course of the disease (n = 75 studies). The findings of PET/CT were correlated with diagnostic CT and clinical follow-up. RESULTS: PET/CT findings resulted in a change of disease staging in 10 patients (32.3%), upstaging in 7 (22.6%) and downstaging in 3 (9.6%). On a lesion analysis, 164 disease sites were detected by PET/CT of which 38 were overlooked by DCT. At mid-treatment, PET was negative in 28 out of 31 patients (90%) with negative predictive value of 96% as all latter patients except for 1, were disease free (mean 15.4 +/- 8.8 months). The positive predictive value of persistent increased 18F-FDG uptake was 100% as 3 patients with latter findings had active disease. On the CT part, 76 residual masses were identified in 22 patients. Increased 18F-FDG uptake was detected in 11 masses in 4 patients who had active disease. Remaining 65 PET negative masses were false positive findings. The positive predictive value of residual CT mass was 14%. CONCLUSIONS: PET/CT is associated with change in staging in approximately 1 out of 3 pediatric patients with HD and NHL. When used for monitoring response to treatment, a negative study is associated with disease-free period, even when residual mass is detected. A positive PET study indicates residual malignant disease.

Adolescent↗
PubMedDate not supplied

Back pain in adolescents: assessment with integrated 18F-fluoride positron-emission tomography-computed tomography.

The aim of the present study was to assess the ability of a novel bone imaging technique to diagnose accurately the cause for back pain as an isolated and presenting complaint in adolescents. An integrated 18F-fluoride positron-emission tomography-computed tomography (PET-CT) study was performed at the same setting without changing the patients' position, followed by generation of fused images of functional and anatomical data. Fifteen subjects were included in the study. The interpretation of PET-CT fused images was based on increased 18F-fluoride uptake and the corresponding CT-located abnormality. Ten patients had positive findings that included 4 cases of spondylolysis (3 of them active), 3 frank fractures (2 of the transverse process and 1 of the facet), 2 osteoid osteomas, 1 osteitis pubis, 1 sacroiliitis, and 2 herniated disks. Three patients presented 2 coexisting pathologies. Treatment was tailored based on final diagnosis. In 5 patients, in whom no abnormality was identified, the back pain resolved spontaneously. The 18F-fluoride PET-CT can detect spinal lesions with high diagnostic accuracy in adolescents with back pain. Considering the associated costs and radiation exposure, it should be used at present only in cases of long-standing and disabling back pain in which other imaging modalities were inconclusive.

Adolescent↗
PubMedDate not supplied

Tumor lesion detection: when is integrated positron emission tomography/computed tomography more accurate than side-by-side interpretation of positron emission tomography and computed tomography?

OBJECTIVES: To determine if there is added value to oncology studies performed with a dedicated in-line positron emission tomography (PET)/computed tomography (CT) scanner as compared with PET read side by side with diagnostic CT (DCT). METHODS: Forty-one consecutive oncology patients referred for PET/CT who had contemporary DCT scans for review were enrolled. Body regions assessed on a DCT scan were assessed on PET/CT and by side-by-side reading of PET and DCT (SBS PET/DCT). Lesions identified on DCT, the CT portion of PET/CT, SBS PET/DCT, and the reading of fused PET/CT images were scored as benign or malignant. The PET portion of the PET/CT study was read by 2 teams: the first read the SBS PET/DCT scan and the other read the complete fused PET/CT scan. For discordant lesions, the final diagnosis was determined by pathologic findings (n = 6) or imaging follow-up (n = 21). RESULTS: Twenty-seven (16.1%) of the 168 lesions were discordant when comparing analysis of fused PET/CT and SBS PET/DCT. Sixteen (9.5%) were fundamentally discordant, and 11(6.6%) were discordant in degree of confidence. For all discordant lesions only, the sensitivity, specificity, negative predictive value, positive predictive value, and accuracy for PET/CT were 100%, 33%, 100%, 94%, and 78%, respectively, and for SBS PET/DCT, they were 38%, 50%, 19%, 73%, and 30%, respectively (P < 0.001 for sensitivity, P = not specific for specificity). The 2 main causes for misclassification on SBS PET/DCT were incorrect localization (n = 12) and changes occurring in the time gap between DCT and PET/CT (n = 4). CONCLUSIONS: In-line PET/CT offers better lesion localization in comparison to the visual fusion of PET and CT, especially for small lymph nodes, lesions adjacent to mobile organs, or lesions adjacent to the chest or abdominal wall.

Adult↗