SPECT myocardial perfusion imaging for the evaluation of left ventricular mechanical dyssynchrony in obese patients.

OBJECTIVE: Left ventricular dyssynchrony (LVD), the loss of coordinated contraction in the left ventricle, is an early sign of heart failure. LVD can be assessed using phase analysis techniques with gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). This study aimed to investigate the impact of obesity on LVD through phase analysis. METHODS: We retrospectively enrolled 152 obese patients and 80 age- and sex-matched nonobese patients who showed normal myocardial perfusion and normal left ventricular ejection fraction (LVEF) on MPI. Phase standard deviation (PSD) and phase histogram bandwidth (PBW), as phase analysis parameters, were compared between patients with and without obesity. RESULTS: Although PSD values were within the normal range (cut-off value >23) for both groups, the PSD values of obese patients were higher than those of the nonobese (20.49 ± 8.66 vs. 14.81 ± 4.93; p < 0.05). PBW values of obese patients were statistically significantly higher than those of the nonobese (57.03 ± 23.17 vs. 41.40 ± 9.96; p < 0.05). The PBW values of obese patients exceeded the normal limits (cut-off value >49). A weak positive correlation was observed between body mass index (BMI) and PBW values in obese patients (r = 0.181, p < 0.05). In patients of normal weight, no correlations were found between BMI and phase analysis parameters. CONCLUSION: LVD may develop in obese patients, even when myocardial perfusion and ejection fraction are preserved. The use of phase analysis with gated SPECT could be an additional finding improving the early detection of left ventricular dyssynchrony in obese patients.

Evaluation of Diastolic Function in Patients with Normal Perfusion and Type 2 Diabetes Mellitus with Gated Single-photon Emission Computed Tomography.

Early identification of diastolic dysfunction of patients with diabetes is important in preventing cardiac events. In this study, we aimed to show that both myocardial perfusion and diastolic function parameters can be evaluated in diabetic patients with possible silent cardiac symptoms using gated single-photon emission computed tomography (G-SPECT). We examined eighty patients: Forty with and forty without diabetes. The patients were compared in terms of systolic and diastolic parameters obtained using G-SPECT. 99mTc-sestamibi was used to obtain 8-frame images in each cardiac cycle, with calculation of the left ventricular ejection fraction (LVEF), peak filling rate (PFR), mean filling rate during the first third of diastolic time (MFR/3), and time to peak filling (TTPF) using the QGS software. G-SPECT results were compared in forty diabetic and forty nondiabetic patients of similar age and sex. Of the diastolic function parameters, PFR was found to be lower in patients with than without diabetes (2.31 ± 0.68 vs. 2.76 ± 0.68, respectively; P = 0.004). The TTPF and MFR/3 in both groups were similar. PFR was negatively correlated with end-diastolic volume and end-systolic volume (ESV) and positively correlated with LVEF. This correlation was stronger in patients with diabetes. The diastolic parameter PFR, obtained using G-SPECT, was significantly lower in patients with than without diabetes. We believe that these parameters should be noted for the early diagnosis or prevention of heart disease in patients with a risk of diastolic dysfunction.

Can Neutrophil/Lymphocyte Ratio be a Predictor for Bone Metastases of Solid Tumors?

Cancer-associated inflammation has been receiving increased attention due to its role in cancer development. It is known that tumors can cause an inflammatory reaction and inflammatory cells play an important role in neoplastic growth. In this study, we aimed to investigate any relationship between bone metastases and the neutrophil-to-lymphocyte ratio (NLR). Patients who were referred for bone scintigraphy to investigate bone metastasis were enrolled in the study. Patients' hematological parameters were obtained from the hospital database retrospectively. Patients with a nonmetastatic bone scan were categorized as Group A (N = 171), patients who had metastatic bone disease without any other organ metastases were categorized as group B (N = 25), and patients who had metastatic bone disease with the other organ metastases were categorized as Group C (N = 48). The median NLR of the patients in Group A was 2.55 (range: 0.38-20.7), in Group B was 2.83 (range: 1.56-31.8), and in Group C was 4.12 (range: 1.79-38). NLR was significantly higher in Group C patients compared to Group A and B patients (P < 0.001). In conclusion, the NLR is significantly associated with the other organ metastases but has no significant correlation with bone metastases.

Evaluating the Role of Routine Prone Acquisition on Visual Evaluation of SPECT Images.

UNLABELLED: Attenuation artifacts reduce our ability to evaluate perfusion of affected myocardial segments. The aim of this study was to evaluate the impact of routine prone-position image evaluation within a stepwise visual interpretation of myocardial perfusion studies. METHODS: We have included 279 consecutive patients who were referred for evaluation of myocardial ischemia. All patients underwent routine electrocardiogram-gated supine SPECT imaging and non-electrocardiogram-gated prone-position SPECT imaging. Three nuclear medicine physicians interpreted the images in the following order: polar maps, supine images, raw images, motion-frozen gated images, and prone images, using a scale of 0-4. Segments with perfusion abnormalities were noted. RESULTS: All physicians reported lower proportions of equivocal evaluations after evaluating prone images (18.3% vs. 4.7%, 19% vs. 11.1%, and 12.2% vs. 6.1%, P < 0.0001, P = 0.0077, and P = 0.0125, respectively). At the prone stage, normalcy rates were 89%, 87%, and 91%. Two physicians had significantly increased normalcy rates at the prone stage (72%-89%, P = 0.039, and 66%-87%, P = 0.006). At the prone stage, a decision reversal to normal or probably normal was observed in 40% (29/72), 33% (17/51), and 43% (21/48). In men, apical, mid, and basal inferior walls and in women apical and mid parts of anterior walls were more likely to be attributed to attenuation. The 2 steps that increased normalcy rates for interpreters were the review of raw images and of prone images. CONCLUSION: Routine prone imaging increases interpretive certainty and interobserver agreement and changes the final evaluation in a substantial number of patients and significantly decreases the number of equivocal evaluations.

Positron emission tomography/computerized tomography imaging of multiple focus of neurolymphomatosis.

Neurolymphomatosis is defined as infiltration of the peripheral nervous system by malignant lymphocytes in the presence of lymphoma. In this case, we described multiple neurol involvement and findings of (18)F-fluorodeoxyglucose positron emission tomography/computerized tomography in a 35-year-old female diagnosed with B-cell lymphoma.

(18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging of extra-medullary plasmacytoma of the ovary.

Extrameduallary plasmacytoma of ovary is extremely rare. We report a case of involvement of ovary in a treated case of plasmacytoma of 2(nd) part of duodenum, which was initially thought to be physiological luteal activity. However, follow up whole body FDG PET-CT scan shows appearance of metabolically active soft tissue mass in left adnexal region which confirmed to be extra-medullary plasmacytoma of ovary on histopathology.

Preeclampsia: is it because of the asymptomatic, unrecognized renal scars caused by urinary tract infections in childhood that become symptomatic with pregnancy?

Preeclampsia is an important disease of pregnancy whose exact etiology is still unknown despite continuing developments in medicine. Although most commonly it is believed to be caused by a defective placentation, in this paper, we hypothesize that the primary underlying problem in the development of preeclampsia can be in kidneys in a greater proportion of cases than it is believed today. The increased intravascular volume and the increased work load of kidneys together with the resulting glomerular hypertrophy may precipitate nephrotic syndrome, which in this case is called "preeclampsia" in a previously affected kidney. Urinary tract infections in childhood leaving silent, unrecognized small scars in the kidneys may be the underlying renal cause which disrupts its silence with an increased work load of kidneys prominently occurring after the midtrimester. The histopathologic finding in kidneys with renal scars after childhood urinary tract infections and in preeclampsia is focal segmental glomerulosclerosis in the majority of cases and this similarity strengthens our hypothesis.

QRS complex duration and dipyridamole gated SPECT findings in the left bundle branch block.

OBJECTIVE: The aim of this study was to investigate the relationship between QRS duration, artifactual perfusion abnormalities, and left ventricular function in patients with left bundle branch block (LBBB) using dipyridamole technetium-99m sestamibi electrocardiography-gated single-photon emission computed tomography (SPECT). METHODS: Twenty-three patients (62 +/- 12.2 years, 18 women, 5 men) with complete LBBB were analyzed. All patients underwent rest-dipyridamole gated SPECT (1-day protocol). To exclude patients with true myocardial ischemia and clearly define artifactual abnormalities owing to LBBB, only patients with normal end-diastolic stress images were involved. Four sets of SPECT images representing ungated rest, ungated stress, and end-diastolic and end-systolic stress images were generated, and the summed defect scores were obtained for each [summed rest score (SRS), summed stress score (SSS), end-diastolic score (EDS), and end-systolic score (ESS), respectively]. QRS durations were measured for both rest and dipyridamole stress. RESULTS: The patients with perfusion abnormalities on ungated rest, ungated stress, or end-systolic stress images had significantly longer minimum QRS duration at rest. These QRS values correlated with SRS and SSS (r: 0.528, P: 0.01 and r: 0.47, P: 0.024, respectively). Analysis of perfusion and functional data demonstrated an inverse correlation between left ventricular ejection fraction (LVEF) and ESS (r: -0.671, P < 0.0001). The patients with end-systolic perfusion abnormalities had significantly lower LVEF rates when compared with the patients with normal perfusion on end-systolic images. CONCLUSIONS: Our results demonstrated that the presence and severity of artifactual perfusion abnormalities owing to LBBB were significantly related to minimum QRS duration. The magnitude of perfusion abnormalities especially on the end-systolic phase seems to adversely affect systolic function of the left ventricle.