(18)F-FDG PET/CT for initial assessment and response monitoring in a case of high grade primary lymphoma of the thyroid gland: A case report and review of literature.

Thyroid lymphoma is a rare disease entity of elderly females. Chronic lymphocytic thyroiditis is said to be the precursor of thyroid lymphoma, suggesting a role of chronic antigen stimulation in the development of the disease. We present a case of male with lymphocytic thyroiditis who presented with painless progressive neck enlargement and pathology revealed features of high grade lymphoma. Staging and posttreatment (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) was performed. This report reemphasizes the role of (18)F-FDG PET/CT in the diagnosis, staging, and assessment of therapy response in patients with extranodal lymphoma, including the primary thyroid lymphoma.

Quantitative assessment of cardiac mechanical synchrony using equilibrium radionuclide angiography.

BACKGROUND: Data on normal parameters of cardiac mechanical synchrony is limited, variable and obtained from small cohorts till date. In most studies, software used for such assessment has not been mentioned. The aim of study is to establish normal values of mechanical synchrony with equilibrium radionuclide angiography (ERNA) in a larger population using commercially available software. METHODS: We retrospectively analysed ERNA studies of 108 patients having low pretest likelihood of coronary artery disease, no known history of cardiac disease, normal electrocardiogram and whose ERNA studies were considered normal by experienced observers. In addition, ten patients diagnosed with dilated cardiomyopathy (DCM) and having LVEF ≤ 40% underwent ERNA. Fourier first harmonic analysis of phase images was used to quantify synchrony parameters using commercially available software (XT-ERNA). Intraventricular synchrony for each ventricle was measured as the standard deviation of the LV and RV mean phase angles (SD LVmPA and SD RVmPA, respectively). Interventricular synchrony was measured as LV-RVmPA. Absolute interventricular delay was calculated as absolute difference between LV and RVmPA (without considering ± sign). All variables were expressed in milliseconds (ms) and degree (°). Intra-observer and inter-observer variabilities were assessed. Cut-off values for parameters were calculated from the normal database, and validated against patient group. RESULTS: On phase analysis, LVmPA was observed to be 343 ± 48.5 milliseconds (174.7° ± 18.5°), SD LVmPA was 16.3 ± 5.4 milliseconds (8.2° ± 2.5°), RVmPA was 339 ± 50.4 milliseconds (171.8° ± 18.5°) and SD RVmPA was 37.3 ± 15.7 milliseconds (18.7° ± 7.2°). LV-RVmPA was observed to be 3.9 ± 21.7 milliseconds (2.9° ± 9.6°) and absolute interventricular delay was 16.3 ± 14.8 milliseconds (7.9° ± 6.1°). The cut-off values for the presence of dyssynchrony were estimated as SD LVmPA > 27.1 milliseconds (>13.2°), SD RVmPA > 68.7 milliseconds (>33.1°) and LV-RVmPA > 47.3 milliseconds (>22.1°). There was no statistically significant intra-observer or inter-observer variability. Using these cut offs, 9 patients with DCM showed the presence of left intraventricular dyssynchrony, 5 had right intraventricular dyssynchrony and 2 had interventricular dyssynchrony. CONCLUSIONS: ERNA phase analysis offers an objective and reproducible tool to quantify cardiac mechanical synchrony using commercially available software and can be used in routine clinical practice to assess mechanical dyssynchrony.

Lymphomatous involvement of epididymis: detection and response assessment with (18)F-FDG PET/CT.

Lymphomatous involvement of epididymis, primary or secondary to extensive extranodal disease, is a rare entity. We describe a case of extranodal non-Hodgkin lymphoma where staging F-FDG PET/CT demonstrated unsuspected lymphomatous involvement of epididymis and restaging FDG PET/CT showed complete response after chemotherapy.

Comparison of software programs for the assessment of left ventricular ejection fraction using 99mTc-tetrofosmin-gated SPECT/CT: correlation with equilibrium radionuclide ventriculography in the Indian population.

OBJECTIVE: The goal of this study was to compare Emory Cardiac Toolbox (ECTb), quantitative gated SPECT (QGS), four-dimensional single photon emission computed tomography (4D-MSPECT) and Myometrix cardiac software programs for the assessment of left ventricular ejection fraction (LVEF) using 99mTc-tetrofosmin-gated SPECT/CT [myocardial perfusion SPECT (MPS)] and correlate them with the LVEF values derived from equilibrium radionuclide ventriculography (ERNV) in patients with known/suspected coronary artery disease (CAD). MATERIALS AND METHODS: A total of 109 patients (80 men, 29 women) were recruited into the study. Fifty-five patients had known CAD and 54 were referred with suspicion of CAD. All the patients underwent ERNV and MPS as per the standard protocol. ERNV was processed using the vendor-provided 'EF analysis' and gated MPS was processed using individual software programs. RESULTS: The mean LVEF on ERNV was 47.9 ± 15.5%. The mean LVEF values for ECTb, QGS, 4D-MSPECT and Myometrix were 51.5 ± 19.6, 51.0 ± 18.6, 57.1 ± 19.3 and 49.7 ± 19%, respectively. On correlation analysis, a very strong positive correlation was observed between LVEF values derived by ERNV and those derived by the MPS software programs: ECTb (r=0.842, P<0.0001), QGS (r=0.835, P<0.0001), 4D-MSPECT (r=0.830, P<0.0001) and Myometrix (r=0.875, P<0.0001). Significant correlation was also seen for LVEFs among the four software programs. Normal cutoff values for ejection fraction on ECTb, QGS, 4D-MSPECT and Myometrix were 56, 52, 54 and 51%, respectively, using a 50% or more cutoff value on ERNV. CONCLUSION: A strong correlation was observed among ECTb, QGS, 4D-MSPECT and Myometrix software programs when compared with ERNV and also between them for assessment of LVEF. However, there are subtle differences in the objective values of ejection fraction generated by individual software, which must be taken into account for clinical studies.