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Aim: To estimate the standard uptake values (SUVs) of Tc-99m methylene-diphosphonate (Tc-99m MDP) from normal skeletal sites in breast cancer patients using quantitative single-photon emission computed tomography (SPECT). Materials and Methods: A total of 60 breast cancer patients who underwent Tc-99m MDP SPECT/CT study at different postinjection acquisition times were included in this study. Based on postinjection acquisition time, patients were divided into four study groups (n_15 each), i.e. Ist (2 h), IInd (3 h), IIIrd (4 h), and IVth (5 h). Image quantification (SUVmax and SUVmean) was performed using Q.Metrix software. Delineation of volume of interest was shaped around different bones of the skeletal system. Results: The highest normal SUVmax and SUVmean values were observed in lumber and thoracic vertebra (8.89 ± 2.26 and 2.89 ± 0.58) for Group I and in pelvis and thoracic (9.6 ± 1.32 and 3.04 ± 0.64), (10.93 ± 3.91 and 3.65 ± 0.97), (11.33 ± 2.67 and 3.65 ± 0.22) for Group II, III and IV, respectively. Lowest normal SUVmax and SUVmean values were observed in humerus and ribs (3.22 ± 0.67 and 0.97 ± 0.18), (5.16 ± 1.82 and 1.18 ± 0.16) for Group I, IV, and in humerus (3.17 ± 0.58 and 0.85 ± 0.26), (3.98 ± 1.12 and 1.04 ± 0.28) for Group II and III, respectively. Significant difference (P < 0.05) noted in SUVmax for sternum, cervical, humerus, ribs, and pelvis with respect to time. However, significant difference (P < 0.05) noted in SUVmean for all skeletal sites with respect to time. Conclusions: Our study shows variability in normal SUV values for different skeletal sites in breast cancer patients. Vertebral bodies and pelvis contribute highest SUV values. Time dependency of SUVs emphasizes the usefulness of routinely acquired images at the same time after Tc-99m MDP injection, especially in follow-up studies. [ABSTRACT FROM AUTHOR]

Aim: In a Nuclear Medicine department, the risk of external and internal contamination in radiation workers is much higher than in other medical radiation facilities. The risk associated with both types of contaminations should be quantified to estimate the radiation dose received by the personal. Here, we designed an in vitro model to see the impact of internal and external contamination of F-18 and Technetium-99 m (Tc-99 m) on DNA damages. Methodology: Chinese hamster lung fibroblast V79 was used for all of the experiments. Irradiation was performed internally and externally (scenarios activity is mixed with the cell line [Internal] and activity kept at 1 cm distance from cell line [external]) using two different diagnostic radioactive sources (Tc-99 m and F-18) of known quantity 37 MBq. Total cumulated activity (MBq-min) was calculated up to one half-life of sources for both internal and external setups. An alkaline single gel electrophoresis technique (comet assay) was used for DNA damage analysis. Olive tail moment (OTM) was used to characterize DNA damage. Results: We have not observed any significant difference (P > 0.05) in OTM between internal and external irradiation for cumulated activity presented before one half-life of both diagnostic isotopes. However, a significant difference in OTM was noted between internal and external irradiation for cumulated activity presented at one half-life of radioactive sources (P < 0.05). DNA damage with internal exposure was found to be 17.28% higher for F-18 and 23% higher for Tc-99 m than external exposure at one half-life of radioactive sources. Overall, we noted greater DNA damage in F-18 as compared to Tc-99 m. Conclusions: Our in vitro study practically demonstrated that internal contamination is more hazardous than external exposure. [ABSTRACT FROM AUTHOR]

Introduction: With the advent of functional endoscopic sinus surgery and coronal computed tomography (CT) imaging, more attention has been paid toward paranasal region anatomy. Detailed knowledge of anatomic variations in paranasal sinus region is critical for surgeons performing endoscopic sinus surgery as well as for the radiologist involved in the pre- and post-operative assessment. The anatomical variants with some accompanying pathologies would directly influence the success of diagnostic and therapeutic management of paranasal sinus diseases. Our study intends to explore the anatomy of paranasal air sinus through CT and to describe its variants, which may predispose to chronic sinusitis and complications in endoscopic sinonasal surgery. Materials and Methods: This was a retrospective study carried out in a tertiary institution. Two hundred and fifty patients without paranasal sinus symptoms who presented for head CT studies and gave consent for a coronal section scan of the paranasal sinuses to be taken in addition to the axial section of the head were included in the study. The CT examination was performed with GE Hispeed-NX/I Base-2002 Dual Slice Helical CT machine. Results: Among 250 study population, 100 were females and 150 males. Among these 423 cases of anatomical variants were observed. The most common anatomical variants were pneumatization of the middle nasal turbinates 30.73%. This is followed by agger nasi cells 21.64%, Haller's cells 22.91%, septal deviation 21.91%, and sphenoid sinus septation (20.18%). Discussion: CT is the gold standard in the radiologic investigation of the paranasal sinuses, sinonasal lesions, and inflammatory disease or pre- and post-surgical assessment. It has the capability of disclosing in greatest detail any anatomical variations, which could be causing or precipitating the sinusitis. [ABSTRACT FROM AUTHOR]

Purpose of the Study: This study aims to compare glomerular filtration rate (GFR) estimated by Gates method using gamma camera (GC) with single plasma sample method (SPSM) in people with normal and abnormal body mass index (BMI) using SPSM as gold standard. Materials and Methods: It was single-center prospective study including 60 voluntary kidney donors. Technetium-99m labeled Diethylene Triamine Pentaacetic Acid (99mTc-DTPA) was administered intravenous under GC. GFR was calculated using Gates Method. After the scan, the subjects were called again after 180 min of injection of 99mTc-DTPA. Then, a 3 ml venous blood sample was obtained from the contralateral arm. Russell's formula was used to determine the GFR by SPSM. Results: Mean GFR calculated by SPSM and Gates' method, was 94.0 ± 15.2 ml/min/1.73 m2 and 87.3 ± 16 ml/min/1.73 m2 respectively. Moderate correlation noted between two methods (r = 0.71, P < 0.0001). Significant correlation noted between GFR calculated by SPSM and Gates method in people with normal BMI (r = 0.92) with no significant statistical difference (P = 0.8). However, only moderate correlation noted between GFR calculated by SPSM and Gates method in people with BMI outside normal range (r = 0.71) with a significant statistical difference (P = 0.0002). Conclusion: Gates method of GFR estimation using GC shows significant correlation with plasma sample technique in people with normal BMI. In people with BMI outside normal range, it significantly underestimates GFR. [ABSTRACT FROM AUTHOR]

Edge packing is a kind of nonuniformity artifact, which usually appears as an accumulation of counts at the edge of the field of view compared to the central region. The common causes of edge packing artifact in the image are defective collimator, noncalibrated photomultiplier tube (PMT), and improper adjustment of deflector plates of CRT. We hereby discuss the occurrence of edge packing artifact due to a problem with the PMTs in the anterior head of gamma camera system during acquisition of bone scintigraphy which mimics as pathological lytic–sclerotic lesion during whole-body image at anterior acquisition. The artifact was successfully removed after the replacement of malfunctioning PMTs. [ABSTRACT FROM AUTHOR]

Excessive skeletal radioisotope uptake in relation to soft tissues along with absent or faint activity in the genitourinary tract on skeletal scintigraphy is known as a "superscan." Prostate cancer is the most common cause of superscan in skeletal scintigraphy due to diffuse skeletal metastases. However, prostate cancer may cause secondary renal osteodystrophy leading to metabolic superscan also. Differentiating between these two entities are important as treatment options are different. We, hereby, describe a case of prostatic adenocarcinoma presented with metabolic superscan on methylene diphosphonate skeletal scintigraphy and demonstrate the utility of single emission computed tomography-computed tomography in differentiating between two entities. [ABSTRACT FROM AUTHOR]

Carotid body tumors, although representing about 65% of head and neck paragangliomas, are rare neoplasms. Doppler ultrasonography, contrast-enhanced computed tomography (CECT), and MRI have been routinely used in the diagnosis of carotid body tumor. We hereby represent a case of 56-year-old male suspected to have lymph node metastasis from carcinoma pyriform sinus detected as carotid body tumor in fluorodeoxyglucose positron-emission tomography-CECT imaging and subsequently confirmed by histopathology. [ABSTRACT FROM AUTHOR]