Bekir Tasdemir

Acoustic radiation force impulse (ARFI) elastography for detection of renal damage in children

BackgroundAcoustic radiation force impulse (ARFI) imaging is a promising method for noninvasive evaluation of the renal parenchyma.ObjectiveTo investigate the contribution of ARFI quantitative US elastography for the detection of renal damage in kidneys with and without vesicoureteral reflux (VUR).Materials and methodsOne hundred seventy-six kidneys of 88 children (46 male, 42 female) who had been referred for voiding cystourethrography and 20 healthy controls were prospectively investigated. Patients were assessed according to severity of renal damage on dimercaptosuccinic acid (DMSA) scintigraphy. Ninety-eight age- and gender-matched healthy children constituted the control group. Quantitative shear wave velocity (SWV) measurements were performed in the upper and lower poles and in the interpolar region of each kidney. DMSA scintigraphy was performed in 62 children (124 kidneys). Comparisons of SWV values of kidneys with and without renal damage and/or VUR were done.ResultsSignificantly higher SWV values were found in non-damaged kidneys. Severely damaged kidneys had the lowest SWV values (P < 0.001). High-grade (grade V-IV) refluxing kidneys had the lowest SWV values, while non-refluxing kidneys had the highest values (P < 0.05). Significant negative correlations were found between the mean quantitative US elastography values and DMSA scarring score (r = −0.788, P < 0.001) and VUR grade (r = −0.634, P < 0.001). SWV values of the control kidneys were significantly higher than those of damaged kidneys (P < 0.05).ConclusionOur findings suggest decreasing SWV of renal units with increasing grades of vesicoureteric reflux, increasing DMSA-assessed renal damage and decreasing DMSA-assessed differential function.

Evaluation of Parathyroid Lesions With Point Shear Wave Elastography

The aim of our study was to evaluate the shear wave velocity (SWV) of parathyroid lesions by point shear wave elastography (SWE) and to compare their stiffness with that of thyroid nodules and normal thyroid parenchyma quantitatively.

What approach should we take for the incidental finding of increased 18F-FDG uptake foci in the colon on PET/CT?

Introduction18F-Fluorodeoxyglucose (18F-FDG) PET/CT represents an imaging modality that is gaining increasingly more prominence in screening, staging, and therapeutic monitoring of malignant diseases. An incidental focus of uptake in different regions of the body is not an uncommon finding during PET/CT imaging. Patients with incidental gastrointestinal tract findings comprise ∼3% of the overall patient group. The aim of the current study was to provide contributory information in relation to the answer on the most appropriate approach in cases with incidental colonic 18F-FDG uptake. Patients and methodsA retrospective examination was performed on PET/CT results of 5258 patients. Of these, 152 were recommended to undergo colonoscopy because of the presence of suspicious foci and 31 underwent colonoscopy within 60 days with biopsy from all visible lesions. These dates were also examined. ResultsOf the 24 patients undergoing colonoscopy with a suspicion of malignancy, five (20.83%) had no pathological findings. Of the 19 (79.17%) cases with a pathological finding in endoscopy, histopathology showed a benign lesion in five (20.83%), premalignant lesion in seven (29.17%), and a malignant lesion in seven (29.17%). Among seven patients undergoing colonoscopy because of a suspicion of inflammatory bowel disease, five were free of pathological signs and two patients with pathological endoscopy findings had nonspecific inflammation as documented by histopathological examination. ConclusionColonoscopic and histopathological examination of the increased foci of colonic 18F-FDG uptake incidentally detected at PET/CT seems to be a plausible approach.

Significance of Hormone Receptor Status in Comparison of 18F -FDG-PET/CT and 99mTc-MDP Bone Scintigraphy for Evaluating Bone Metastases in Patients with Breast Cancer: Single Center Experience

BACKGROUND Fluorine-18 deoxyglucose positron emission tomography computed tomography (18F-FDG-PET/ CT) and bone scintigraphy (BS) are widely used for the detection of bone involvement. The optimal imaging modality for the detection of bone metastases in hormone receptor positive (+) and negative (-) groups of breast cancer remains ambiguous. MATERIALS AND METHODS Sixty-two patients with breast cancer, who had undergone both 18F-FDG-PET/CT and BS, being eventually diagnosed as having bone metastases, were enrolled in this study. RESULTS 18F-FDG-PET/CT had higher sensitivity and specificity than BS. Our data showed that 18F-FDG- PET/CT had a sensitivity of 93.4% and a specificity of 99.4%, whiel for BS they were 84.5%, and 89.6% in the diagnosis of bone metastases. κ statistics were calculated for 18F-FDGPET/CT and BS. The κ-value was 0.65 between 18F-FDG-PET/CT and BS in all patients. On the other hand, the κ-values were 0.70 in the hormone receptor (+) group, and 0.51 in hormone receptor (-) group. The κ-values suggested excellent agreement between all patient and hormone receptor (+) groups, while the κ-values suggested good agreement in the hormone receptor (-) group. CONCLUSIONS The sensitivity and specificity for 18F-FDG-PET/CT were higher than BS in the screening of metastatic bone lesions in all patients. Similarly 18F-FDG-PET/CT had higher sensitivity and specificity in hormone receptor (+) and (-) groups.

A comparison of acoustic radiation force impulse imaging and scintigraphy in the functional evaluation of the major salivary glands.

PurposeThis study aimed to determine the efficacy of acoustic radiation force impulse (ARFI) imaging for the functional assessment of salivary glands by comparing ARFI with salivary gland scintigraphy. Materials and methodsWe prospectively evaluated 60 parotid (P) glands and 60 submandibular (SM) glands of 30 patients using salivary gland scintigraphy and ARFI elastography. The average pixel uptake and the excretion fraction (EF) in the P and SM glands were determined scintigraphically. The degree of stiffness in the P and SM glands at prelemon and postlemon stimulation periods were measured elastographically with ARFI. Changes in the degree of stiffness of the P and SM glands were also calculated with lemon stimulation. The scintigraphic and elastographic parameters were then compared statistically. ResultsWe found a moderate linear correlation between the excretion function and the changes in the degree of stiffness of the P and SM glands induced by lemon stimulation (P<0.001, r=0.661; P<0.001, r=0.530, respectively). We also found a weak positive correlation between the EF and the degree of stiffness of the P and SM glands in the prelemon stimulation period (P=0.001, r=0.405; P<0.001, r=0.480, respectively). However, we did not find any significant correlation between other scintigraphic and elastographic parameters. ConclusionARFI imaging may play a role in the determination of the EF of P and SM glands by measuring tissue elasticity changes with lemon stimulation. However, ARFI does not seem to be a suitable substitute for scintigraphy in the evaluation of the parenchymal function of P and SM glands.

Is there any significance of lung cancer histology to compare the diagnostic accuracies of (18)F-FDG-PET/CT and (99m)Tc-MDP BS for the detection of bone metastases in advanced NSCLC?

Aim of the study Bone scintigraphy (BS) and fluorine-18 deoxyglucose positron emission tomography computed tomography (18F-FDG-PET/CT) are widely used for the detection of bone involvement. The optimal imaging modality for the detection of bone metastases in histological subgroups of non-small cell lung cancer (NSCLC) remains ambiguous. The aim of this study was to compare the efficacy of 18F-FDG-PET/C and 99mTc-methylene diphosphonate (99mTc-MDP) BS in the detection of bone metastases of patients in NSCLC. Specifically, we compared the diagnostic accuracies of these imaging techniques evaluating bone metastasis in histological subgroups of NSCLC. Material and methods Fifty-three patients with advanced NSCLC, who had undergone both 18F-FDG-PET/CT and BS and were eventually diagnosed as having bone metastasis, were enrolled in this retrospective study. Results The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 18F-FDG-PET/CT and BS were 90.4%, 99.4%, 98.1%, 96.6%, 97.0% and 84.6%, 93.1%, 82.5%, 93.2, 90.8%, respectively. The κ statistics were calculated for 18F-FDG-PET/CT and BS. The κ-value was 0.67 between 18F-FDG-PET/CT and BS in all patients. On the other hand, the κ-value was 0.65 in adenocarcinoma, and 0.61 in squamous cell carcinoma between 18F-FDG-PET/CT and BS. The κ-values suggested excellent agreement between all patients and histological subgroups of NSCLC. Conclusions 18F-FDG-PET/CT was more favorable than BS in the screening of metastatic bone lesions, but the trend did not reach statistical significance in all patients and histological subgroups of NSCLC. Our results need to be validated in prospective and larger study clinical trials to further clarify this topic.

Assessment of Technetium-99m Labeled Macroaggregated Albumin Rhinoscintigraphy for the Measurement of Nasal Mucociliary Transport Rate: Intratest, Interobserver, and Intraobserver Reproducibility

Objectives. The measurement of mucociliary transport velocity by rhinoscintigraphy with Tc-99m-macroaggregated albumin (99mTc-MAA) is reliable measure of mucociliary clearance. The aim of this study is to assess the intratest, interobserver, and intraobserver reproducibility of nasal mucociliary transport rate (NMTR) measurement. Materials and Methods. Twenty-two subjects were evaluated to determine intratest reproducibility and a group of 35 subjects was examined to determine inter- and intraobserver reproducibility. Rhinoscintigraphy with 99mTc-MAA was used to measure NMTR in all study subjects. Paired NMTR measurements were compared using a range of statistical methodologies. Intraclass correlation coefficients (ICC) and repeatability coefficients and Bland-Altman plots were applied to assess the degree of intratest, interobserver, and intraobserver variation. Results. Statistical analysis of test and retest experiments demonstrated the statistical equivalence of intratest NMTR measurements, interobserver NMTR measurements, and intraobserver NMTR measurements. The intratest ICC, interobserver ICC, and intraobserver ICC were 0.96, 0.83, and 0.91, respectively, indicating that intratest and intraobserver reproducibility are excellent and interobserver reproducibility is good. Conclusions. Rhinoscintigraphy using 99mTc-MAA results in highly reproducible measurement of NMTR. The use of radionuclide imaging in measuring NMTR results in excellent intratest and intraobserver reproducibility and good interobserver reliability.

Improvement of minimally invasive parathyroidectomy outcomes by real time ultrasonography performed by a surgeon and radiologist team.

AIMS Minimally invasive parathyroidectomy (MIP) has become the first line of treatment for primary hyperparathyroidism caused by solitary parathyroid adenoma. In order to increase the sensitivity of high-resolution ultrasonography (hUS), surgeon performed ultrasonography (SUS) has been increasingly used preoperatively. However, a radiologist and surgeon performing ultrasonography (RSUS) has not been a usual practice. In this study, we aimed to evaluate the clinical contribution of RSUS on MIP. MATERIAL AND METHODS From 2012 to 2014, a total of 30 consecutive patients (4 male, 26 female, mean age 48.87+/-14.52 years) with solitary parathyroid adenoma, were included in the study. All patients underwent preoperative hUS and Technetium-99m sestamibi scintigraphy. In patients, demographic characteristics, diagnostic tools used, levels of biochemical parameters, duration of operation, and length of hospital stay were recorded. RESULTS Adenomas were successfully localized by US in all patients and the surgical approach was determined according to this localization. Parathyroidectomy with MIP was successfully performed under local anesthesia in all patients. Mean operation time was 19.87+/-3.35 min. Postoperative PTH and calcium values were significantly decreased. All patients were discharged from the hospital in the same day. None of the patients had complications such as recurrent laryngeal nerve injury, hematoma, or injury to nearby organs. None of the patients had drains placed. CONCLUSIONS Adenoma is well localized by US and thus, MIP can be completed under local anesthesia. US provides a very important clinical contribution to the success of MIP. In addition to these, RSUS helps in determining the location of the incision and the shortest way to achieve the lesion; therefore, it provides a small incision and shortens duration of the operation with a minimal dissection.

Effect of R-CHOP chemotherapy on liver and mediastinal blood pool 18F-FDG standardized uptake values in patients with non-Hodgkin’s lymphoma☆

AIM We aimed to investigate the impact of chemotherapy on (18)F-FDG uptake in the liver and mediastinal blood pool (MBP) among patients with non-Hodgkins lymphoma. METHODS Twenty-three patients with NHL underwent baseline, interim, and postchemotherapy (18)F-FDG PET/CT. SUVmax and SUVmean values of the liver and MBP at imaging time were compared statistically. RESULTS We did not find any significant differences between the liver and mediastinum SUVmean and SUVmax values (P>.05). CONCLUSIONS Our study demonstrates that the (18)F-FDG uptake in the liver and MBP are not significantly affected by R-CHOP chemotherapy in patients with NHL.

Evaluation of Clinical Contributions Provided by Addition of the Brain, Calvarium, and Scalp to the Limited Whole Body Imaging Area in FDG-PET/CT Tumor Imaging

Purpose. The aim of this study was to detect additional findings in whole body FDG-PET/CT scan including the brain, calvarium, and scalp (compared to starting from the base of the skull) in cancer patients and to determine contributions of these results to tumor staging and treatment protocols. Materials and Methods. We noted whether the findings related to the brain, calvarium, and scalp in 1359 patients had a potential to modify staging of the disease, chemotherapy protocol, radiotherapy protocol, and surgical management. We identified rates of metastatic findings on the brain, calvarium, and scalp according to the tumor types on FDG-PET/CT scanning. Results. We found FDG-PET/CT findings for malignancy above the base of the skull in 42 patients (3.1%), one of whom was a patient with an unknown primary tumor. Twenty-two of the metastatic findings were in the brain, 16 were in the calvarium, and two were in the scalp. Conclusion. This study has demonstrated that addition of the brain to the limited whole body FDG-PET/CT scanning may provide important contributions to the patients clinical management especially in patients with lung cancer, bladder cancer, malignant melanoma, breast cancer, stomach cancer, and unknown primary tumor.