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Objective: The aim of this study was to compare planar technetium-99m-dimercaptosuccinic acid (Tc-DMSA) cortical scintigraphy with Tc-DMSA single-photon emission computed tomography (SPECT) for the detection of renal cortical scars in patients with chronic kidney disease stage-3 (CKD-3)., Patients and Methods: Data of 40 patients (mean age: 43.7±15.3 years, 29 men, 11 women) who underwent planar Tc-DMSA along with regional Tc-DMSA SPECT for the detection of renal cortical scars were prospectively evaluated. All the patients had CKD-3, with a mean serum creatinine level of 2.23±1.85 g/dl. Planar and SPECT Tc-DMSA images were evaluated by two nuclear medicine readers independently. Each kidney was divided into 12 cortical segments. A cortical segment was recorded as abnormal if it had reduced or absent radiotracer activity. The linear correlation coefficient (r value) for the number of abnormal segments detected between readers was calculated for planar imaging, SPECT, and between the two techniques for both the readers., Results: For both observers, the average correlation coefficient for SPECT (r=0.87) and planar imaging (r=0.90) was high (P<0.0001). A moderately strong linear correlation was also observed between readers for planar imaging and SPECT (r=0.78 and 0.71, P<0.0001). There was no significant difference in the average number of abnormal segments detected by planar versus SPECT imaging: 2.1 for planar imaging and 2.8 for SPECT (P=0.06, two-tailed). In 15% of patients, SPECT detected cortical defects not appreciated on planar imaging., Conclusion: Tc-DMSA renal cortical imaging using dual-head SPECT offers no statistically significant diagnostic advantage over planar imaging for the detection of cortical defects in patients with CKD-3.

Purpose: The purpose of this study was to assess the role of fluorine 18 ((18)F)-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG PET-CT) in evaluating various parameters in patients with surgical scar site recurrence in cervical carcinoma., Methods: Data of all patients with cervical cancer (n = 329) who underwent PET-CT at our institute between 2005 and 2013 was reviewed. Of these 329 patients, 132 patients who were surgically treated and underwent restaging/follow-up PET-CT were included in the present study for final analysis. Tumor recurrence at the abdominal surgical scar site was looked for. Abnormal uptakes suggestive of active disease at other sites were also noted. Maximum standardized uptake value was measured for all the lesions. Patients with scar site recurrence were taken as cases (n = 6), whereas the remaining patients served as controls (n = 126). Comparison with conventional imaging modalities was made wherever available. Histopathological examination was always sought for., Results: The incidence of scar site recurrence after surgery was found to be 4.5% (6/117). A total of 56 of 132 patients had recurrent disease, including 6 patients with scar site recurrence. All of the patients with scar site recurrence also had recurrent disease at other sites (local, nodal, or distant). Conventional imaging modalities were available in 4 of these 6 patients and detected scar site recurrence in 3 of those 4 patients. In patients with scar site recurrence, the mean ± SD time to scar site recurrence was 14.0 ± 10.9 months (median, 10 months; range, 7-36 months). Significant difference was seen between cases and control for International Federation of Genecology and Oncology stage (P = 0.001) and nodal recurrence (P = 0.007). Additionally, age, nodal recurrence, distant recurrence, and scar site recurrence were significantly associated with death., Conclusions: Scar site recurrence carries a poor prognosis, and the incidence is much higher than previously known when PET-CT is used as a modality for its detection.

We report a 15-year-old patient with tuberous sclerosis complex or Bourneville's disease with history of generalized tonic-clonic seizure for last 2 years and was currently on antiepileptic medication. He also had a history of left nephrectomy for renal cell carcinoma clear cell type. The patient had multiple adenoma sebaceum over the nasolabial region, ash leaf spots over the lower limbs, a Shagreen patch over the back, and multiple calcified tubers in the subependymal region. He was then referred for the skeletal scintigraphy to look for skeletal lesions, which revealed involvement of bilateral humeri, tibiae, and iliac bones accurately characterized on SPECT/CT.

PET/computed tomography evaluation of neuroendocrine tumors is gaining prominence with the availability of novel pet radiotracers, such as (18)F-DOPA and gallium 68 somatostatin peptide derivatives. These tumors have unique properties and hence the basis of use of these new radiotracers. Prominent centers worldwide have reported the usefulness of these PET tracers in diagnosis and clinical decision making. Portability of 68Ge/68Ga generators has also helped in more widespread use of these somatostatin peptide derivatives as PET radiotracers. This article reviews established and potential roles of these novel PET radiotracers in diagnosis, management, and prognosis of neuroendocrine tumors., (Copyright © 2015 Elsevier Inc. All rights reserved.)

(99m)Tc-Methylene diphosphonate (MDP) triple phase bone scintigraphy (BS) has a role in early diagnosis of Kienbock's disease, especially when the X-ray is negative. Early diagnosis can result in prompt management of the patient since wrist pain in older individuals due to aging may go unnoticed or be due to other diagnoses with the production of greater damage and eventually a worse prognosis. Herein, we present a case report of a 29-year-old female with Kienbock's disease in whom the X-ray was negative and MRI incorrect. The (99m)Tc-MDP SPECT/CT BS helped the diagnosis of the disease in an early stage (stage 1) and had a clinical impact on the patient's management., (Copyright © 2014 Elsevier España, S.L.U. and SEMNIM. All rights reserved.)

Urinary bladder diverticular carcinomas are uncommon with a lesser incidence of 0.8-10% and its diagnosis still remains a challenge. Cystoscopy is the most reliable method, but evaluating diverticulum with narrow orifices is difficult. Before the initiation of appropriate treatment, proper detection of bladder diverticular carcinoma and its locoregional and distant sites of involvement is necessary. Here, we present a case of 48-year-old male with urinary bladder diverticular carcinoma detected by forced diuretic (18)F-fluorodeoxyglucose positron emission tomography/computerized tomography ((18)F-FDG PET/CT). This case also highlights the significance of forced diuretic (18)F-FDG PET/CT in the detection, staging, and response evaluation of bladder diverticular carcinoma.

Objective: To compare findings with 2-deoxy-2-((18)F)fluoro-D-glucose positron emission tomography combined with computed tomography ((18)F-FDG-PET/CT) with findings obtained using ultrasound (US), magnetic resonance imaging (MRI), and CT in patients with proven tubercular tubo-ovarian masses., Methods: Seventeen patients with proven tubercular tubo-ovarian masses underwent (18)F-FDG-PET/CT imaging and the findings were compared with US (for all patients), MRI (for 9 patients), CT (for 4 patients), and laparotomy or laparoscopic findings (for 14 patients)., Results: Eleven patients (64.7%) had unilateral tubo-ovarian masses, with activity in 6 masses (35.3%); 4 patients (23.5%) had bilateral tubo-ovarian masses, with activity in all masses; and 2 patients (11.76%) had unilateral space-occupying lesions, with activity in 1 lesion. The detection rates of tubo-ovarian masses with (18)F-FDG-PET/CT were similar to, but the characterization of adnexal masses was less than, those obtained with CT or MRI. Finally, (18)F-FDG-PET/CT was equally accurate as laparoscopy or laparotomy in detecting the presence, laterality, and activity of tubo-ovarian masses., Conclusion: Imaging with (18)F-FDG-PET/CT is noninvasive and appears to be clinically useful for the diagnosis of tubercular tubo-ovarian masses., (Copyright © 2012 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.)

Purpose: To assess the radiation exposure to nuclear medicine staff at a positron emission tomography-computed tomography (PET-CT) centre with high patient throughput., Materials and Methods: This prospective study included 70 adult patients who underwent 18F-fluorodeoxyglucose (FDG) PET-CT for their clinical indications. The patients' actual injected FDG activity was calculated by subtracting the syringe activity (post-injection) from the loaded syringe activity (pre-injection). The instantaneous exposure to nuclear medicine staff involved in PET-CT imaging was measured. The instantaneous dose rate of the physicians was recorded during FDG injection and that of the technologist was recorded during the patient's positioning, respectively, at 1.0-m distance from the anterior chest using a calibrated portable gamma-ray survey meter., Results: The average FDG activity injected in adult patients was 308.5 MBq (range 173.1-438.8 MBq). The instantaneous exposure to the nuclear medicine (NM) physician during the injection time was 31 μSv/h (14-60 μSv/h). The instantaneous exposure to the NM technologist during positioning was 18 (10-34) μSv/h. With an average of 10 patients per day, the quarterly dose to physicians was 628 μSv and to technologists 182 μSv for 300 patients. The extrapolated annual dose was 2.5 mSv for physicians and 0.7 mSv for technologists, respectively., Conclusion: Instantaneous exposure of nuclear medicine staff involved in PET-CT imaging at a busy tertiary care centre is within permissible limits of the International Commission on Radiological Protection (ICRP-103) (total <100 mSv over 5 years and not >50 mSv in a single year) and atomic energy regulatory board (total <100 mSv over 5 years and not >30 mSv in a single year).

Aim: Adrenal metastasis in renal cell carcinoma (RCC) is uncommon. The present study was aimed to evaluate the role of fluoro-deoxy-glucose positron emission tomography (FDG PET)/computed tomography (CT) in the detection of adrenal metastasis in patients with RCC., Materials and Methods: A total of 9 FDG PET/CT scans were performed in 4 patients (3 males, 1 female; median age: 53.5 years, range: 52-73 years). Of 9 PET/CT scans, 2 scans were done for initial staging, 2 for restaging, and 5 for evaluation of treatment response. PET/CT image interpretation and analysis was performed qualitatively (visually) and semiquantitatively. Absence of uptake in postchemotherapy PET/CT scan was considered as complete response and a fall in SUV by more than 50% of baseline value, as significant response., Results: Patients 1 and 2 underwent staging FDG PET/CT. Patient 1 had undergone left radical nephrectomy 13 years back for left-sided RCC. Current FDG PET/CT revealed appearance of right RCC with adrenal metastasis. PET/CT of patient 2 demonstrated right adrenal and distant metastases. PET/CT done for restaging in patient 3, revealed right adrenal and abdominal lymph nodal metastasis. In patient 4, PET/CT revealed solitary adrenal metastasis. Magnetic resonance imaging findings were consistent with adrenal metastasis in this patient. Patient 1 received sunitinib and interferon chemotherapy along with radiotherapy and showed partial response on PET/CT scans done at 6, 17, 23, and 33 months from the initial study. PET/CT of patient 3 demonstrated the progression of disease (nonresponder)., Conclusion: FDG PET/CT appears to be useful for staging, treatment response evaluation, and recurrence detection in patients with RCC having adrenal metastasis.

Aim: to evaluate the treatment response in patients with recurrent colorectal cancer (CRC) using FDG PET/CT., Materials and Methods: a total of 32 recurrent CRC patients (21 males, 11 females; mean age, 52.8 years) were included in this retrospective study. All patients underwent a baseline and follow-up FDG PET/CT scans after chemotherapy. Of 32 patients, 23 patients had follow-up carcinoembryonic antigen (CEA) levels., Results: on qualitative analysis of baseline and follow-up FDG PET/CT studies, there were 20 nonresponders and 12 were responders. On quantitative analysis, there were 19 nonresponders and 13 were responders. In responders, baseline and follow-up mean SUV(max) were 11.8 ± 10.1 and 3.7 ± 4.1, respectively (significant decrease, P = 0.001). Among nonresponders, baseline and follow-up mean SUV(max) were 8.1 ± 5.2 and 14.1 ± 9.0, respectively (significant increase, P = 0.003). There was no association between response and different factors like age, sex, diagnosis, extent of the lesions, and number of lesions., Conclusion: FDG PET/CT appears to be useful modality in evaluating chemotherapy response and can differentiate responders from nonresponders in recurrent CRC patients.

Aim: To determine the efficacy of positron emission tomography-computed tomography using F-18 fluoro-deoxy-glucose (F-18 FDG PET-CT) in diagnosing the recurrence of renal cell carcinoma (RCC) in patients treated earlier with partial or radical nephrectomy., Methods: We assessed 63 patients with suspected recurrent RCC after nephrectomy. PET-CT findings were interpreted as positive if the focal area of FDG uptake in the abdomen or outside the abdomen was more than the surrounding background tissue. The final diagnosis of the recurrence of RCC was based on histological examination and/or clinical follow-up and conventional imaging modalities., Results: A total of 103 PET-CT studies were done in these 63 patients, of which 63 studies were true positive, 30 studies were true negative, seven studies were false negative and remaining three studies were false positive. In 63 true-positive scans, PET-CT showed 109 lesions. Of these, 28 lesions were in the lungs, 21 lesions were at a locoregional site, 21 were in the bones, 12 in the retroperitoneal lymph nodes and 27 at other sites. The sensitivity, specificity and accuracy of PET-CT were 90, 91 and 90%, respectively., Conclusion: Our results seem to confirm the useful role of PET-CT in the evaluation of post-surgical recurrence in patients who had undergone radical surgery for RCC.

Aim: To evaluate the treatment response of rhenium-188 (¹⁸⁸Re) tin colloid radiosynovectomy (¹⁸⁸Re-RSV) in patients with inflammatory knee joint conditions refractory to conventional treatment., Materials and Methods: Sixty-one knee joints in 48 patients with chronic synovitis caused by various inflammatory knee joint diseases refractory to conventional therapy were included in this prospective study. All patients were assessed clinically for pain, tenderness, joint swelling, mobility, analgesic intake, and blood pool activity on bone scan. Different scores were assigned to all these parameters. RSV of knee joint was done using intra-articular injection of 555 MBq of ¹⁸⁸Re tin colloid. Response was assessed at 3, 6, and 12 months using various clinical parameter scores and blood pool bone scan mentioned above and categorized as responders and nonresponders on the basis of change in percentage of cumulative scores., Results: Of the 61 joints, 57 were responder and four were nonresponder at 3-month post-RSV. Out of 57 responders, seven had recurrence on further follow-up (three at 6 months and four at 12 months). There was a statistically significant reduction in clinical parameters cumulative scores at 3, 6, and 12 months when compared with baseline (P<0.0001) in responder group. Blood pool scinitgraphy also showed decrease in blood pool activity compared with the baseline. There was statistically significant association between the responder group and shorter duration of disease (P=0.011). Patients having normal or minor X-ray changes, little or no swelling, mild tenderness, and better mobility were independently associated with good response., Conclusion: ¹⁸⁸Re tin colloid synovectomy is a useful treatment modality in patients with chronic inflammatory knee joint conditions refractory to conventional treatment. Patients with shorter duration of disease, normal or minor X-ray findings, little or no swelling, mild tenderness, and better mobility are better candidates for RSV.

Background: One-third of patients with colorectal cancer (CRC) are likely to have a recurrence within the first 1-2 years. Conventional imaging modalities have limitations in detecting recurrent disease early. The purpose of this study was to assess the usefulness of fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in the detection of recurrence in patients with CRCs., Methods: One hundred and eighty-three patients, who were earlier treated with surgery and/or chemotherapy/radiotherapy, underwent 269 PET/CT studies for the detection of recurrence. The final diagnosis was made on the basis of histological analysis or clinical and imaging follow-up., Results: The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value in detecting recurrent CRC using F-FDG-PET/CT were 87, 90, 88, 93, and 80%, respectively. PET/CT was found to have limitations in detecting microscopic disease and small-sized lesions. The common cause of false-positive PET/CT results was infective and inflammatory pathology in our setup., Conclusion: PET/CT showed high sensitivity, specificity, and accuracy for the detection of recurrent disease in patients, who were earlier treated for CRC. PET/CT can be considered as a useful diagnostic tool in these patients.

The common childhood cancers are leukemia, CNS tumors, lymphomas, soft-tissue tumors (such as rhabdomyosarcoma and fibrosarcoma), neuroblastoma, malignant bone tumors, germ cell tumors with neoplasms of gonads and hepatic tumors. Usually the conventional imaging modalities, such as x-ray, ultrasound, computed tomography (CT) and MRI, are being routinely used for the management of these pediatric malignancies. However, most of these modalities provide structural information and are lacking in functional/metabolic status of these malignancies. Recently, PET and PET/CT have emerged as a functional diagnostic imaging modality for the management of various cancers in adult population. Up to now most of the data published in the literature are on PET alone. PET used in conjunction with CT is useful as it provides an enhanced view of the anatomical details and the malignant focus then can be located with highest accuracy. PET and PET/CT has been found to be useful in, for example, CNS tumors, lymphomas, soft-tissue tumors, neuroblastoma, malignant bone tumors and germ cell tumors. PET/CT has a limited role in early diagnosis, however, it plays an important role in initial staging, treatment response evaluation and detection of metastatic disease in these cancers. Despite the fact that PET/CT has better diagnostic value when compared with conventional imaging, such as CT and MRI, in the management of many pediatric cancers, there are certain limitations. PET/CT has a limited role in detection of lesions smaller than 5 mm, well-differentiated tumors and tumors with low metabolic rate. Many infections and inflammation can lead to false-positive PET/CT results. In the present review we will discuss the various clinical indications of PET and PET/CT in pediatric cancers.

Object: The object of the present study was 3-fold: 1) to study regional cerebral perfusion before and after endoscopic third ventriculostomy (ETV) in patients with obstructive hydrocephalus by using (99m)Tc ethyl cysteinate dimer SPECT: 2) to study any correlation between clinically successful third ventriculostomy and CSF flow across the third ventriculostomy; and 3) to determine any changes in hormone profile following ETV., Methods: The authors prospectively studied 15 patients with aqueductal stenosis who underwent ETV during the last 2 years. All the patients underwent pre- and postoperative MR imaging, brain (99m)Tc ethyl cysteinate dimer SPECT, and hormone profile studies., Results: Eight patients were infants. The mean follow-up duration was 17.6 months. Thirteen patients (86.7%) exhibited clinical improvement after surgery. In all patients with clinical improvement the studies documented CSF flow through the ventriculostomy site. Clinical progress could be correlated with SPECT changes in 14 cases (93.3%). In the 13 clinically successful cases, 12 were substantiated by improvement on SPECT scans, whereas in the 2 failed cases, SPECT images revealed no improvement of perfusion defects. Hormone analysis conducted in 14 patients revealed hyperprolactinemia in 8, low triiodothyronine values in 2 patients, and hypocortisolemia in 1, which was reversed after ETV., Conclusions: Clinical improvement is not well correlated with a decrease in ventricular size following ETV. Brain SPECT is a valuable tool for the follow-up of patients with hydrocephalus after ETV, particularly in cases in which MR imaging findings are not clear. There are subtle hormonal changes in patients with hydrocephalus that may improve following ETV.

Rhenium-188 labeled tin (Sn) microparticles were developed for pain palliation therapy in the patients suffering from synovitis with acute pain. The rhenium tin microparticles were prepared using stannous chloride and freshly eluted (188)ReO(4)(-) from (188)W/(188)Re generator. The aggregated colloidal particles, packed in a spherical form after boiling for 90-120min were analyzed using electron microscope. The size, surface morphology and stability of microparticles were analyzed by changing temperature and volume conditions. The small colloidal particles clustered and formed spherical microparticles. The 90% of microparticles were in 5-10microm range, after 90min and 120min of boiling. The radiolabeling efficiency was improved to 98% after centrifugation for 10min at 3500rpm. The formulations were stable but the increase in volume had inverse effect on labeling efficiency. No leak was observed from knee area up to 24h with 15-20mCi injection of (188)Re-Sn microparticles. The relief in treated patients, from the pain and inflammation, was observed clinically and by (99m)Tc-MDP perfusion scan.

This is a report of 2 patients with Lyme disease who initially presented with severe constipation, which progressed to ascending muscular weakness resembling acute idiopathic polyneuritis, with neuropsychiatric symptoms, severe urinary retention, and hyponatremia. These symptoms resolved following proper antibiotic therapy.