1209 Objectives: Gastric emptying scintigraphy (GES) is used to quantify overall gastric emptying in patients with dyspeptic symptoms including nausea, vomiting, post-prandial fullness, and early satiety. The contribution of regional abnormalities to disorders of gastric motility is not routinely assessed by scintigraphy. We analyzed fundal and whole-stomach gastric emptying in patients with moderately-delayed gastric emptying on standard GES. A cohort of patients with normal gastric emptying on standard GES was used to define normal fundal and whole-stomach emptying values which were then used to analyze the gastroparesis (GP) group. Defining subgroups of patients with GP may be instrumental in tailoring therapies to fit specific mechanisms of dysfunction. Methods: IRB approval was obtained. By review of nuclear medicine reports, we retrospectively identified a convenience sample of 40 patients who underwent standard GES which demonstrated moderately-delayed gastric emptying (gastric retention of 15-35% at 4-hrs). 25 patients were selected with normal emptying at GES by SNMMI guidelines. Using a commercial software package, a ‘fundal’ ROI was assigned by visually bifurcating the stomach in equal portions. Clearance from the fundal and entire ROIs was modeled by fitting an exponential curve to the geometric mean of decay- and background-corrected counts (Excel, version 2011, Microsoft Corporation) and deriving fundal and entire stomach clearance T½s. Normal values for fundal and whole-stomach emptying were developed based on measurement of the normal cohort and applied to the GP cohort. Results: Normal half-times of emptying (hours) were 0.81 ± 0.36 for whole stomach and 0.64 ± 0.35 for the fundus. In the GP group, the average whole-stomach (2.67 ± 0.83) and fundal (1.61 ± 0.88) half-times (hours) were significantly greater (Table) (p<<0.001). Based on an upper value of 1.53 hour for whole stomach and 1.34 hour for fundus, 1 (2.5%) of the 40 GP patients demonstrated normal whole stomach emptying rates while fully 17 (42%) of patients with GP had normal T½ fundal emptying. Discussions/Conclusions: There is regional information inherent in GES beyond a unidimensional value of total gastric emptying which we have exploited in our analysis of fundal vs. whole-gastric emptying. This can be used to develop an improved understanding of the underlying pathophysiology of gastric dysfunction. Over 40% of GP patients demonstrated normal fundal emptying in spite of abnormally-delayed whole-stomach emptying, suggesting a pyloric rather than generalized motility disorder. Our findings strengthen the relevance of regional motility measurements with implications for choosing optimal therapy in differing subsets of patients and demonstrates the role that scintigraphy can play in defining patient groups.

2003 Objectives: This exhibit will familiarize the reader with a range of diverse applications of scintigraphy for evaluation of bodily leaks and collections while demonstrating the added value of SPECT/CT for this purpose. Areas covered will include the lymphatic, urinary, CSF, vascular, and hepatobiliary systems. Methods: This case-based image-rich educational exhibit will demonstrate various applications of a multimodal scintigraphic approach for diagnostic evaluation of bodily leakages with emphasis on dynamic imaging and SPECT/CT, based on the experience of a large academic-based institution. We intend to discuss leaks and collections related to CSF, and genitourinary, lymphatic, vascular, and hepatobiliary systems, among others. Our presentation will especially include emphasis on the seminal contribution of SPECT/CT imaging to correlation and the final diagnosis. Discussion: Numerous physiologic processes employ circulation of wanted or efflux of unwanted materials to appropriate locations within or without the body. Homeostasis is heavily reliant on the appropriate functioning and integrity of these systems and their disruption, as may occur from disease, accident, or iatrogenic injury, can lead to intra- or extra-compartmental leakage and collections, serious complications requiring prompt identification and characterization to inform management. While radiologic contrast- and non-contrast based imaging is instrumental in the evaluation of extravascular and intercompartmental collections, radiologic methods may be limited in evaluating dynamic and physiologic processes in given clinical scenarios. Scintigraphic imaging is a well-established modality for evaluation of leaks and collections. While use of dynamic imaging is indispensable for determination and characterization of many types of leak, anatomic correlation of findings on planar scintigraphy may be insufficient. We will illustrate how use of SPECT/CT can overcome limitations of scintigraphy by overlaying and correlating the functional information, portrayed on scintigraphy, onto an anatomic background, as provided by computed tomography. Conclusions: This educational exhibit is an overview of the contribution of scintigraphy and SPECT/CT in the evaluation of an assortment of collections and leaks throughout the body. While clinical examination and other radiologic modalities may be limited, a multimodal scintigraphic approach, including SPECT/CT, can serve as a critical tool for diagnosis and management guidance. Figure 1

Aim: To investigate the association between glycemic control represented by glycated hemoglobin (HbA1c) level and the value of 4-h gastric retention on nuclear scan. Methods: We retrospectively reviewed records of diabetic patients who had 4-h nuclear gastric emptying study, with documented 4-h retention value, between January 1st, 2002 and July 30th, 2014 and had HbA1C level close to the time of the study. We divided our cohort into patients with good glycemic control (HbA1C < 7, group A), fair control (7-9, group B), and poor control (> 9, group C). The 4-h retention value and symptoms were compared between the 3 groups. Results: Our cohort included 299 patients; mean age was 59 +/- 14. The median interval between performing gastric emptying study and measuring HbA1C was 41 days. There were 94 patients in group A (HbA1C 6.1 +/- 0.4), 131 patients in group B (HbA1C 7.9 +/- 0.5), and 74 patients in group C (HbA1C 10.9 +/- 1.6). The mean gastric retention value was different between the three study groups, 8.3% +/- 17, 11.5% +/- 19, and 14.4% +/- 21, respectively (P =.03). Conclusion: This is the first study to show that HbA1C level is significantly associated with the 4-h retention value on nuclear gastric emptying scan. (C) 2017 Elsevier B.V. All rights reserved.

Ga citrate is frequently used in the workup of fever of unknown origin. Here, we report a case of avid Ga-citrate in bilateral gluteal regions of a patient with a history of free silicon injection buttock augmentation referred for suspected diagnosis of sarcoidosis. CT findings were equivocal for inflammation/infection in the buttock region, and nuclear scintigraphy allowed for more definitive diagnosis.

Ga-67 citrate is frequently used in the workup of fever of unknown origin. Here, we report a case of avid Ga-67-citrate in bilateral gluteal regions of a patient with a history of free silicon injection buttock augmentation referred for suspected diagnosis of sarcoidosis. CT findings were equivocal for inflammation/infection in the buttock region, and nuclear scintigraphy allowed for more definitive diagnosis.

Introduction: Delayed gastric emptying is currently defined as ≥10% retention at 4 hours on gastric emptying scintigraphy. This cutoff is based on a landmark study done in healthy asymptomatic subjects. Limited data are available regarding gastric emptying parameters in symptomatic patients, and the relation between gastric emptying results and patients' symptoms. We aim to explore these relationships in this study. Methods: We studied 309 patients with clinical features suggestive of gastroparesis, who underwent GES between 01/2013 and 06/2014. We recorded the retention rates at hours 2 and 4, as well as symptoms of nausea, vomiting, fullness, bloating, postprandial abdominal pain, and early satiety. After excluding patients with rapid gastric emptying (defined as < 16% retention at two hours), we divided our cohort into 3 groups based on 4 hour retention of < 4%, 4-9%, and ≥10%. SAS v9.3 software was used for statistical analysis. Results: In evaluating the overall cohort of these 214 symptomatic patients, distribution of retention showed a median retention value of 44.5% at hour 2, and 8.5% at hour 4. These results are different from the median value reported in asymptomatic subjects at hour 2 of 24%, and at hour 4 of 1.2%. Of the 214 patients, 107 (50%) were diabetic. There were no significant differences between groups in regards to symptom of bloating (p 0.26), early satiety (p 0.85), or postprandial abdominal pain (p 0.62). The relation between the three groups and nausea and vomiting approached statistical significance (p 0.054); 50% of patients reported symptom of nausea and vomiting in the < 4% group, 67.4% in the 4-9% group and 71.6% in the ≥10% group. No statistically significant correlation was found in symptoms and GES results in diabetics. Conclusion: 1) The retention time cutoffs in the previous landmark trial done in normal subjects might not be applicable to patients with symptoms of gastroparesis. The cutoff values in our study challenges the validity of the current threshold of 10%. 2) Symptoms are unreliable predictors of gastric emptying function. Therefore, it is essential to evaluate gastric emptying in patients with symptoms suggestive of gastroparesis.Table 1: GES Results and Symptoms

Introduction: Rapid gastric emptying is a clinical phenomenon that has not been emphasized in the published literature. In this study, we aim to identify the prevalence of rapid gastric emptying amongst patients suspected of having gastroparesis and the role of symptoms in this form of gastric dysmotility. Methods: We studied 309 patients with symptoms suggestive of gastroparesis who underwent gastric emptying study between January 2013 and June 2014. We recorded the retention rates at hours 2 and 4, symptoms of nausea and vomiting, bloating, postprandial abdominal pain, and early satiety. We defined rapid gastric emptying as < 16% retention at two hours based on the first quartile value in asymptomatic patients described in a previous study. Patients with prokinetic use within 48 hours prior to gastric emptying study were excluded. SAS v9.3 software was used for statistical analysis. Results: Among 309 patients, 89 patients (28.8%) met the criteria for rapid emptying. Predominant symptoms were nausea and vomiting (53.9%) and bloating (50.6%), while 18% reported symptoms of early satiety and 4.5% reported postprandial abdominal pain. Thirty-six patients with rapid gastric emptying carried a diagnosis of diabetes mellitus. Bloating was more prevalent in patients with rapid emptying compared to the others (50.6% versus 31.8%, P 0.002). No statistically significant differences were noted in nausea and vomiting (p 0.079), postprandial abdominal pain (p 0.17), early satiety (p 0.97), or frequency of diabetes (p 0.11) between the two groups. Conclusion: 1) Rapid gastric emptying is often found in patients with symptoms thought to be caused by gastroparesis. 2) Nausea, vomiting, and bloating were the predominant symptoms in patients with rapid gastric emptying. Bloating was significantly more common in patients with rapid gastric emptying compared to the rest of our cohort. 3) Distinguishing rapid from delayed gastric emptying may be essential to direct treatment in these patients. 4) Large, prospective trials are warranted to further explore this phenomenon.

1038 Learning Objectives 1.To understand the various modalities for evaluating vertebral compression fractures. 2. To understand the unique challenges that the elderly osteoporotic population might pose and the significant role of bone scintigraphy. Summary: Vertebral compression fractures represent a common cause of severe back pain among the elderly osteoporotic population. X-ray, CT scan, MRI and bone scan are the various modalities available for diagnosis of vertebral compression fractures. Vertebroplasty, kyphoplasty or sacroplasty are the interventions used to manage compression fractures. Bone scintigraphy is used to confirm the presence of fracture, estimate the acuteness of the fracture or to predict response to intervention. The elderly osteoporotic population presents a diagnostic challenge with non-specific or ill-localized pain, claustrophobia, motion artifact, multiple fractures, medical implants, severe pain and atypical radiological findings. Bone scan is frequently helpful in such equivocal cases. The following scintigraphic presentations might be encountered: 1) A classical vertebral compression fracture on both CT scan and bone scintigraphy, 2) In elderly patients with multiple radiographic fractures, bone scintigraphy will be able to detect the most acute lesion likely responsible for the patient’s symptoms and guide management appropriately. 3) The reactive bone response might be delayed and variable in elderly osteoporotic population and a negative exam merits close follow up and re-evaluation as indicated. Examples of various scintigraphic patterns and correlative radiological images for vertebral compression fractures in the elderly osteoporotic population will be included for illustration.

1070 Learning Objectives 1. To identify the various scintigraphic patterns that are indicative of chronic cholecystitis on hepatobiliary studies via illustrations. 2. To recognize unusual patterns that might explain patient’s symptoms and be suggestive of the need of surgical intervention through specific examples. Summary: Chronic cholecystitis results from long standing inflammation resulting in loss of gallbladder (GB) function and can present as recurrent abdominal pain or dyspeptic symptoms requiring cholecystectomy. US and Hepatobiliary imaging are often used in conjunction and form the main stay of establishing a diagnosis of chronic cholecystitis. Hepatobiliary scintigraphy (HIDA scan) is the primary imaging procedure utilized for diagnosis of acute cholecystitis. However, there is no single definite pattern to indicate chronic cholecystitis. In the course of performing HIDA scan, several findings suggesting chronic rather than acute GB disease might be encountered. Recognition of these abnormal scintigraphic patterns should suggest chronic GB disease that can most often be confirmed with US. The various scintigraphic patterns that might represent chronic cholecystitis on a HIDA scan are: 1) delayed GB filling with normal biliary to bowel transit, 2) delayed biliary to bowel transit with normal GB filling (no prior analgesic or CCK administered), 3) slow filling of GB, 4) irregular or eccentric GB filling, 5) faint or very small contracted GB, 6) band or septa across GB, 7) photopenic defects in GB, 8) poor response to sincalide (CCK) with low EF. Examples of the above scintigraphic patterns with correlative radiological imaging and pathology would be included for illustration.