Isa Burak Guney

Evaluation of vascularized graft reconstruction of the mandible with Tc-99m MDP bone scintigraphy

AimThe aim of this study was to evaluate the value of bone scintigraphy for the assessment of graft viability following vascularized bone grafts in patients with mandibular reconstruction.MethodsWe investigated 16 patients with vascularized grafts from the fibula (13 patients) and iliac crest (3 patients) in the last 8 years. For the follow up of all these patients, Tc-99m MDP bone scintigraphy was performed between 2-10 days postoperatively. SPECT study was included in 5 patients. For the evaluation of the grafts, a six-grade scoring system was used. The grading system was based on a comparison of tracer uptake between graft and the cranium. The uptake was defined as increasing from grade 6 to grade 1.ResultsThirteen of the 16 grafts had an uncomplicated clinical course. Complications in the graft occurred in three patients. In the analysis of planar scintigrams, patients with uncomplicated healing showed increased uptake in 12 of the 13 grafts (grade 1-3) and 1 showed the same level tracer uptake compared to cranium (grade 4). In the failed 3 grafts, decreased uptake was observed (grade 5 and 6). In 5 patients, SPECT was performed in addition to planar imaging. In these patients, 4 of the 5 grafts had an uncomplicated clinical course and 1 had a complicated one. In the analysis of SPECT images, while all the grafts with an uncomplicated clinical course exhibited increased uptake (grade 1-3), the failed graft showed decreased uptake (grade 6).ConclusionThree-phase bone scintigraphy performed within 10 days after the mandibular reconstruction is a useful tool to monitor the viability and early complications of vascularized mandibular bone grafts. SPECT is also recommended. It may contribute to interpretation of the bone scans and to precise assessment of graft viability.

Thyroid hemiagenesis: a report of three cases and review of the literature

Thyroid hemiagenesis resulting from the failure of embryologic development of one thyroidal lobe is a very rare anomaly. It is usually incidentally discovered during the investigation of accompanying thyroid disorders. Here we report three cases with right lobe agenesis in two patients and left lobe agenesis in one patient. Two of them were hyperthyroid, while the other euthyroid patient had a thyroid mass.

Role of technetium-99m N,N-ethylenedicysteine renal scintigraphy in the evaluation of differential renal function and cortical defects.

Purpose: This study was performed to evaluate the effectiveness of technetium-99m N,N-ethylenedicysteine (Tc-99m EC) in comparison to technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) scintigraphy. Differential renal function (DRF) was calculated by both methods and the cortical-phase images of dynamic Tc-99m EC scintigraphy were evaluated for parenchymal defects. Materials and Methods: A total of 62 patients with various kidney disorders ranging in age from 1 to 44 years underwent both Tc-99m DMSA and Tc-99m EC scintigraphy. Tc-99m EC summed images of the cortical phase and Tc-99m DMSA images were evaluated visually and quantitatively. Visual analysis was used to define renal parenchymal abnormalities. Quantitative analysis was used in the calculation of DRF. The Tc-99m DMSA scan was taken as the gold standard, and the summed Tc-99m EC scan findings were compared against it. Results: The images obtained with Tc-99m DMSA and Tc-99m EC scintigraphy revealed 99 and 97 focal defects, respectively. The 2 renal parenchyma defects located in the ventral middle sections remained undetected with Tc-99m EC scintigraphy. DRF of the kidneys in each patient was compared using both radiopharmaceuticals. Highly positive correlation between the differential function of these 2 investigations was found (R = 0.91, P = 0.001). The values of mean DRF of the left kidney on Tc-99m EC and Tc-99m DMSA images were 45.8 ± 19.1 and 45.0 ± 20.4, respectively. There were no significant differences (P > 0.05). Conclusion: This study suggests that although Tc-99m DMSA scintigraphy remains the gold standard method for evaluating parenchymal abnormalities, Tc-99m EC scintigraphy can be a reliable single-modality study to evaluate renal cortical defects, DRF, perfusion, drainage of the urinary system, and indirect evidence of vesicoureteric reflux with the added advantage of low radiation exposure to the patient.

Effectiveness of diuretic injection on the measurement of differential renal function using Tc-99m DMSA in patients with a dilated renal pelvis.

Aim: The aim of this study was to evaluate the effectiveness of diuretic injection for the measurement of differential renal function (DRF) with technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) scintigraphy in patients with a dilated pelvis. Materials and Methods: A total of 46 patients who were referred for both technetium-99m-L,L-ethylenedicysteine (Tc-99m L,L-EC) and Tc-99m DMSA imaging and found to have a dilated collecting system on Tc-99m EC scintigraphy were studied. Four to 5 hours after intravenous injection of Tc-99m DMSA, imaging was performed in the supine position, and posterior, anterior, left and right lateral, and left and right posterior oblique views were taken. After this study, furosemide was administered intravenously and 30 minutes later, additional images in the anterior and posterior views were obtained. Results: The kidneys were evaluated into 2 groups. Group 1 comprised 12 kidneys that had an obstructive curve pattern on Tc-99m EC scans. Group 2 comprised 34 kidneys that had a nonobstructive dilated renogram curve pattern. DRF of the kidneys in each patient were calculated, and the values obtained from the standard and diuretic DMSA scans were compared with each other for all patients and each group. Considering all the patients, the values of mean DRF on both standard and diuretic DMSA images were 55.4% ± 21.2% and 55.4% ± 21.5%, respectively. There were no significant differences between DRF values of each kidney obtained by the 2 methods. When we compared the DRF values in groups 1 and 2, there were again no significant differences. In group 1, the values of mean DRF on standard and diuretic images were 51.7% ± 13.7% and 51.6% ± 13.9%, respectively, and in group 2, the values of mean DRF were 56.7% ± 23.4% and 56.7% ± 23.6%, respectively. Conclusion: In view of our study, diuretic administration seems to be an unnecessary intervention because it has no effect on the accuracy of DRF measurements using DMSA scintigraphy in patients with a dilated collecting system whether it is obstructed or not.

Prognostic significance of neutrophil/lymphocyte ratio (NLR) and correlation with PET–CT metabolic parameters in small cell lung cancer (SCLC)

PurposeThe aim of this study is to detect the prognostic significance of neutrophil/lymphocyte ratio (NLR) in SCLC and to evaluate the relation with 18F-FDG PET–CT metabolic parameters (PET–CT MPs).MethodsDemographic parameters, laboratory values including NLR and other clinical variables were analyzed in 112 patients with small cell lung cancer (SCLC) and 54 of these patients had results of metabolic parameters detected with 18 FDG PET–CT [including SUVmax, SUVmean, metabolic tumor volume (MTV), whole body MTV (WBMTV), TLG (total lesion glycolysis), whole body TLG (WBTLG)] were evaluated for survival analyses.ResultsMean and median overall survival (OS) and progression-free survival (PFS) were found to be significantly longer in cases with NLR < 4 compared with NLR > 4 in totally. Also stage, performance status, response to first-line therapy, LDH, and lymphocyte count were found to be prognostic for OS and PFS. MTV, WBMTV and WBTLG were found to be prognostic for both OS and PFS, while SUVmax found to be significant for OS. Patients with NLR ≥ 4, MTV ≥ 60.1, WBMTV ≥ 120 and WBTLG ≥ 1000 points had lower OS and PFS. A moderate positive correlation was found between NLR and SUVmean (r: 0.36), SUVmax (r: 0.34), TLG (r: 0.39), MTV (r: 0.51), WBMTV (r: 0.40), and WBTLG (r: 0.46).ConclusionThere is relationship between PET–CT metabolic parameters and NLR in SCLC. Highest correlation was found with NLR and MTV, WBMTV, and WBTLG, and evaluation of NLR together with these parameters predicts survival times and tumor biology more clearly in SCLC.

Super Scan Caused by Parathyroid Carcinoma Observed Both in 18F-FDG PET/CT Scan and Tc-99m MDP Bone Scintigraphy

Super scan is a well-known finding described in skeletal scintigraphy characterized by uniform symmetrically increased radiopharmaceutical uptake by bones and consequently diminished renal parenchymal activity. Sy et al. hypothesized that the faint visualization of renal cortex in bone scintigraphy might be the result of increased uptake of radiopharmaceutical by pathologic bones and reduced phosphate excretion. The super scan on 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has been observed in various conditions such as prostate cancer, lung cancer, renal adenocarcinoma, gastric cancer and primitive neuroectodermal tumor of the kidney. Herein we report the first case of super scan in a 68-year-old-woman with parathyroid carcinoma observed both in 18F-FDG PET/CT and Tc-99m methylene diphosphonate bone scintigraphy. There were extensive hypermetabolic lesions throughout the skeleton in 18F-FDG PET/CT. In contrast to the intense hypermetabolism of the skeleton; the liver, skeletal muscles of the limbs, mediastinum, bowel and especially the brain showed very low FDG uptake. Additionally, there was increased skeletal radiotracer uptake relative to soft tissue, and faint genitourinary tract activity in bone scintigraphy.

HCC Locoregional Therapies: Yttrium-90 (Y-90) Selective Internal Radiation Therapy (SIRT)

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and the third cause of cancer death globally with most deaths occurring within 1 year of diagnosis. HCC is the sixth most common malignancy worldwide [1–3]. Transplantation and resection remain the only potentially curative options [4]. Locoregional therapies such as chemoembolization (TACE) and radiofrequency ablation have an established palliative role in select patients [5–9]. Targeted molecular therapies now have a recognized role, with sorafenib demonstrating improved survival in patients with advanced HCC [10, 11]. Selective internal radiation (SIRT) treatment with Y-90 Microsphere goals are to increase the time to progression, extend overall survival, potentially downsize or downstage tumors for liver resection, ablation or transplantation, and provide palliation of symptoms. Y-90 Microsphere is a highenergy beta-emitting isotope with no primary gamma emission. The maximum energy of the beta particles is 2.27 MeV with a mean of 0.93 MeV. The maximum range of emissions in tissue is 11 mm with a mean of 2.5 mm. The half-life is 64.1 h. Following administration, 94% of the radiation is delivered in 11 days. Y-90 Resin Microspheres (SIR-Spheres) consist of biocompatible polymer resin microspheres of a median diameter of 32.5 μm (range between 20 and 60 μm) loaded with yttrium-90. The resin microspheres are small enough to become lodged in the arterioles within the growing rim of the tumor but are too large to pass through the capillaries and into the venous system. Each vial has 40–80million spheres. Potential advantage is higher coverage of the tumor [12]. Y-90 Glass Microspheres (Therasphere, MDS Nordion, Canada) are 20–30 μm in diameter. TheraSphere® glass microspheres are minimally embolic and do not occlude macrovessels and have a potential benefit in less perfused tumors. TheraSphere® microspheres penetrate and lodge within the tumor arteriolar capillaries, where they emit lethal beta radiation that is localized to the surrounding tumor tissue. Each vial has 1.2–8 million spheres [13]. The treatment decision with Y-90 Microsphere is made at the multidisciplinary tumor council. Inclusion criteria for SIRT treatment are liver-dominant or liver-only disease, good performance status (ECOG/WHO PS 0–2), life expectancy >3 months, and adequate liver function (bilirubin <34 μmol/ L or 2.0 mg/dL). Exclusion criteria are infiltrative tumor type, Bbulk disease^ (tumor volume >70% of the target liver volume or tumor nodules too numerous to count), AST or ALT >5 × ULN, bilirubin >2 mg/dL, tumor volume >50% combined with an albumin <3 g/dL, previous external beam radiation therapy to the liver, ascites or are in clinical liver failure, greater than 20% lung shunting of the hepatic artery blood flow determined by technetium-99 m macroaggregated human albumin (99mTc-MAA) scan, and pre-assessment angiogram that demonstrates abnormal vascular anatomy that * İsa Burak Güney isaburak@gmail.com