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Background: Although different gastric shapes are encountered in gastric emptying scintigraphy (GES), it is not known whether gastric shape is related to gastric emptying (GE) or symptoms., Aim: To investigate different stomach shapes observed during GES and examine their associations with GE, body weight, and gastrointestinal (GI) symptoms., Methods: This was a retrospective review of GES studies performed at our institution. Patients with prior gastric surgery were excluded. A classification of gastric shapes included: crescentic, J-shaped, reversed-L, cylindrical, and bag-like. Gastric shapes were correlated with GE, BMI, and GI symptoms using PAGI-SYM., Results: 397 GES studies were reviewed (317 females, age 40.0 ± 20.3 years, BMI 27.8 ± 13.8 kg/m 2 ). Gastric shapes were: 41.8% crescentic/comma-shaped, 34.0% J-shaped, 19.9% reversed L-shape, 2.8% cylindrical, and 1.5% bag-like. BMI was highest in crescentic/comma-shaped stomachs (30.1 ± 12.4 kg/m 2 ) and lowest in bag-like stomachs (25.2 ± 9.9 kg/m 2 ; p = 0.022). Delayed GE was most pronounced in bag-like stomachs (34.4 ± 33.1% retention at 4 h) and lowest in reversed-L shape (10.3 ± 15.6% retention at 4 h; p = 0.008). Regurgitation severity was greatest in bag-like stomachs (2.2 ± 1.5) compared to milder symptoms in reversed-L shape (1.3 ± 1.4; p = 0.029). Heartburn severity was increased in bag-like stomachs (2.3 ± 1.6) while patients with cylindrical stomachs reported least heartburn severity (1.1 ± 1.3; p = 0.11)., Conclusions: A classification system based on five gastric shapes observed during GES showed that crescent-shaped stomach was the most common shape and correlated with higher BMIs. Delayed GE was most pronounced in bag-like stomachs and lowest in reversed-L stomachs. Regurgitation and heartburn severity were greatest in bag-like stomachs with milder symptoms in reversed-L stomachs. Thus, gastric shape during GES is associated with gastric emptying, BMI, and symptom severity., (© 2024 John Wiley & Sons Ltd.)

Introduction: Whole gut transit scintigraphy (WGTS) can detect delayed colonic transit (CT), different types of CT delays, and assess upper GI tract transit., Aim: To delineate the frequency of different types of CT patterns in patients with chronic constipation (CC), determine the relationship between these CT patterns and upper GI tract transit abnormalities, and assess how symptoms relate to different colonic transit patterns., Methods: Retrospective review of patients who had WGTS for CC. Patients completed a modified PAGI-SYM questionnaire to assess symptoms. Patients ingested a standard solid (Tc-99m egg sandwich)-liquid (In-111 water) meal to assess solid meal gastric emptying (GE), liquid GE, small bowel transit (SBT), and geometric center of colonic activity at 24, 48, and 72h., Results: One hundred and eighty six patients underwent WGTS. Main symptoms were constipation (41%), nausea (24%), and bloating (22%). CT assessment showed 32% of patients had normal transit, 31% colonic inertia (CI), 28% functional rectosigmoid obstruction (FRS0), and 9% generalized slow colonic transit (GSCT). GE was delayed in 36%; more commonly in CI and FRSO. SBT was delayed in 19%; more commonly in GSCT and CI. Patients with CI had less bowel movements per week whereas patients with normal CT had more bm/week., Conclusions: In this series of patients with symptomatic constipation, WGTS assessment showed delayed colonic transit in 68% of patients, with 31% having colonic inertia, 28% a functional rectosigmoid obstruction pattern, and 9% generalized delay in colonic transit. Abnormalities in GE and SBT were present in 36 and 19%. WGTS is helpful to document delayed colonic transit (CT), assess the pattern of the delay in CT, and determine if there are upper GI transit abnormalities., (© 2024. The Author(s).)

Glucagonlike peptide-1 (GLP-1) receptor agonists (RAs) are being increasingly used for glycemic control in patients with diabetes and for weight loss and weight management in obese subjects. There has been recent public awareness of the potential of GLP-1 RAs to delay gastric emptying and cause gastroparesis. By delaying gastric emptying, these agents can complicate the clinical evaluation of patients on these drugs by affecting diagnostic testing for gastroparesis. This article discusses GLP-1 RAs and their effects on gastric emptying, gastric food retention, and gastroparesis. This article highlights how physicians should be attuned to the gastric side effects of these popular therapeutic agents for blood glucose control in people with diabetes and for weight loss and weight management in obese patients., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Dynamic antral contraction scintigraphy (DACS) has been used to evaluate for gastric dysmotility by measuring antral contraction frequency and ejection fraction (EF). Fourier phase image analysis has the potential to assess gastric antral contractions for dyssynchrony as has been used for analyzing nuclear cardiology ventriculography (multigated acquisition studies) for cardiac dyssynchrony. The aims of this study were to determine whether Fourier phase analysis helps to characterize antral motility physiology, whether Fourier phase analysis correlates with conventional gastric emptying scintigraphy (GES), and which DACS parameters may aid in diagnosing gastric dysmotility, particularly delayed gastric emptying (GE). Methods: DACS and GES of healthy volunteers ( n = 22) were compared with patients ( n = 99) with symptoms of gastroparesis. New DACS Fourier phase analysis software was developed. Results: GE was delayed ( n = 53) or normal ( n = 46) in patients. There was a linear correlation between the time for the stomach to empty 50% of the meal and the percentage total proximal and distal in-phase antral pixels at 30 min ( r = 0.37, P = 0.0001) and 60 min ( r = 0.26, P = 0.007). In healthy volunteers, the mean proximal-to-distal ratio of in-phase antral pixels increased from 1.67 (30 min) to 2.65 (120 min) ( P = 0.035), and EF increased from 23% (30 min) to 32% (120 min) ( P = 0.022). Multivariable regressions of percentage total proximal and distal in-phase antral pixels (30 min) and EF (60 min) were the best predictors of abnormal GE (adjusted odds ratio, 3.30 [95% CI, 1.21-9.00] and 2.97 [95% CI, 1.08-8.21], respectively). Conclusion: This study used Fourier phase analysis to analyze DACS in healthy volunteers and patients with symptoms of gastroparesis. In addition to establishing reference values, new physiologic information on antral motility was obtained. In healthy volunteers, there was an increasing proximal-to-distal ratio of in-phase antral pixels and antral EF over time after meal ingestion. The percentage total proximal and distal in-phase antral pixels at both 30 and 60 min correlated well with GE values for the time for the stomach to empty 50% of the meal. For symptomatic patients, the percentage total proximal and distal in-phase antral pixels at 30 min and the EF at 60 min after meal ingestion correlated with delayed GE on conventional GES. Thus, Fourier phase analysis of DACS appears to have potential to further aid in diagnosing gastric dysmotility in GES., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Gastric emptying scintigraphy (GES) measures total gastric retention after a solid meal and can assess intragastric meal distribution (IMD). Water load satiety test (WLST) measures gastric capacity. Both IMD immediately after meal ingestion [ratio of proximal gastric counts after meal ingestion to total gastric counts at time 0 (IMD 0 )] and WLST (volume of water ingested over 5 min) are indirect measures of gastric accommodation. In this study, IMD 0 and WLST were compared with each other and to symptoms of gastroparesis to gauge their clinical utility for assessing patients with symptoms of gastroparesis. Patients with symptoms of gastroparesis underwent GES to obtain gastric retention and IMD 0 , WLST, and filled out patient assessment of upper GI symptoms. A total of 234 patients with symptoms of gastroparesis were assessed (86 patients with diabetes, 130 idiopathic, 18 postfundoplication) and 175 (75%) delayed gastric emptying. Low IMD 0 <0.568 suggesting initial rapid transit to the distal stomach was present in 8% and correlated with lower gastric retention, less heartburn, and lower volumes consumed during WLST. Low WLST volume (<238 mL) was present in 20% and associated with increased severity of early satiety, postprandial fullness, loss of appetite, and nausea. Low IMD 0 is associated with less gastric retention and less heartburn. Volume of water consumed during WLST, while associated with IMD 0 , has associations with early satiety, postprandial fullness, loss of appetite, and nausea. Thus, IMD 0 and WLST appear to overlap somewhat in their assessment of gastric physiology in adults with symptoms of gastroparesis but relate to different dyspeptic symptoms. NEW & NOTEWORTHY IMD 0 and WLST were assessed for their clinical utility in assessing patients with symptoms of gastroparesis. Low IMD 0 is associated with less gastric retention and less heartburn. Volume of water consumed during WLST, while associated with IMD0, has associations with early satiety, postprandial fullness, loss of appetite, and nausea. IMD 0 and WLST appear to overlap somewhat in their assessment of gastric physiology in adults with symptoms of gastroparesis but relate to different dyspeptic symptoms.

Background: Patients with gastroparesis and related disorders have symptoms including early satiety, postprandial fullness and bloating. Buspirone, a 5-HT 1 receptor agonist, may improve fundic accommodation., Aim: To determine if buspirone treatment improves early satiety and postprandial fullness in patients with symptoms of gastroparesis., Methods: This 4-week multi-centre clinical trial randomised patients with symptoms of gastroparesis and moderate-to-severe symptoms of fullness (Gastroparesis Cardinal Symptom Index [GCSI] early satiety/postprandial fullness subscore [ES/PPF]) to buspirone (10 mg orally) or placebo three times per day. The primary outcome was a change in the ES/PPF from baseline to 4 weeks. The primary analysis was per protocol intention-to-treat ANCOVA of between-group baseline vs. 4-week differences (DoD) in ES/PPF adjusted for baseline ES/PPF. Results are reported using both nominal and Bonferroni (BF) p values., Results and Conclusions: Ninety-six patients (47 buspirone, 49 placeboes; 92% female, 50% delayed gastric emptying, 39% diabetic) were enrolled. There was no between-groups difference in the 4-week ES/PPF primary outcome: -1.16 ± 1.25 (SD) on buspirone vs -1.03 ± 1.29 (SD) on placebo (mean DoD: -0.11 [95% CI: -0.68, 0.45]; p = 0.69). Buspirone performed better than placebo in patients with severe-to-very severe bloating at baseline compared to patients with none to moderate: (ES/PPF DoD = -0.65 vs. 1.58, p TX*GROUP  = 0.003; p BF  = 0.07). Among individual GCSI symptoms, only bloating appeared to improve with buspirone vs. placebo., Conclusions: Patients with moderate-to-severe early satiety/postprandial fullness and other symptoms of gastroparesis did not benefit from buspirone treatment to improve the ES/PPF primary outcome compared with placebo. There was a suggestion of the benefit of buspirone in patients with more severe bloating., Trial Registration: ClinicalTrials.gov NCT0358714285., (© 2023 John Wiley & Sons Ltd.)

Background: Total gastric retention (TGR) from gastric emptying scintigraphy (GES) is used for diagnosing gastroparesis (Gp), but correlates poorly with patients' symptoms. Regional intragastric meal distribution (RIMD) can also be assessed from GES. This study classified patients' meal distribution as proximal or distal to relate RIMD to symptoms of Gp., Methods: GES studies in patients (n = 193) and control subjects (n = 21) were selected for RIMD analysis. Patients completed Patient Assessment of Upper Gastrointestinal Symptoms (PAGI-SYM) for symptom severity before GES. TGR was analyzed using % TGR, and RIMD used a proximal/distal gastric count ratio (PDCR). Results were classified as proximal or distal RIMD at 0, 1, 2, and 4 h postprandially based on their PDCR being above or below the median value of the patients., Results: Patients with delayed GE and immediate post-meal ingestion distal distribution had more severe early satiety and regurgitation. Distal distribution at 1 h had more severe early satiety and loss of appetite compared to proximal distribution. Patients with delayed GE and proximal distribution at 4 h had more severe nausea, retching, and vomiting compared to 4 h distal distribution. Severely delayed 4 h proximal distribution had more nausea than severely delayed 4 h distal distribution., Conclusions: Increased early distal IMD in patients with delayed GE was associated with regurgitation and early satiety whereas increased late proximal IMD was associated with nausea, retching, and vomiting. Differentiating proximal from distal meal distribution patterns helps to relate symptoms to gastric dysfunction and may be helpful for directing therapy., (© 2022 John Wiley & Sons Ltd.)

Patients often are evaluated for gastroparesis because of symptoms occurring with meals. Gastric emptying scintigraphy (GES) is used for gastroparesis diagnosis, although results are not well correlated with gastroparesis symptoms. The aim of this study is to assess relationships between gastroparesis symptoms, gastric emptying (GE), and gastric accommodation (GA). Patients with symptoms of gastroparesis completed the Patient Assessment of Upper GI Symptoms (PAGI-SYM) and recorded symptoms during GES and water load satiety test (WLST), an indirect assessment for GA. A total of 109 patients with gastroparesis symptoms were assessed. Symptom severity increased after GES meal for stomach fullness, belching, nausea, abdominal burning, and abdominal pain. There was no difference in symptoms after meal between patients with delayed ( n = 66) and normal ( n = 42) GE. Diabetic patients ( n = 26) had greater gastric retention than idiopathic patients ( n = 78), but idiopathic patients had greater postprandial nausea, stomach fullness, and abdominal pain. Water consumed during WLST averaged 421 ± 245 mL. Idiopathic patients had greater nausea scores during WLST than diabetic patients. In comparison to those with normal water consumption (≥238 mL; n = 80), patients with impaired water ingestion (<238 mL; n = 26) had increased stomach fullness, early satiety, postprandial fullness, and loss of appetite on PAGI-SYM. Patients with delayed and normal GE had similar symptom profiles during GES and WLST. Idiopathic patients had less gastric retention but more symptoms after GES meal and after WLST compared with diabetic patients. Patients with impaired water consumption during WLST had increased symptoms by PAGI-SYM. These data suggest that impaired GA, rather than GE, may be important in explaining postprandial symptoms in patients with symptoms of gastroparesis. NEW & NOTEWORTHY Patients with delayed and normal gastric emptying (GE) had similar symptom profiles during gastric emptying scintigraphy (GES). Idiopathic patients with symptoms of gastroparesis had less gastric retention by GES; but more symptoms after GES meal and after water load satiety test (WLST) compared with diabetic patients. In patients with symptoms of gastroparesis, symptoms after WLST increased with decreasing water consumption. Early satiety and loss of appetite were associated with decreased water consumption during WLST. Thus, impaired accommodation and perhaps visceral hypersensitivity are important in explaining postprandial symptoms in gastroparesis.

Background: Gastric emptying scintigraphy (GES) reports percent retention at 1, 2, and 4 h. Time to empty half the meal (T ½ ) could simplify GE reporting., Aims: To compare the performance of GES T ½ to 1-, 2-, and 4-h retention., Methods: GES studies were reviewed; results determined according to retention at 1, 2, and 4 h. T ½ was determined using 3 methods: (1) GES curve fitting using 0, 0.5, 1, 2, 3, and 4 h data; (2) linear interpolation using 0, 0.5, 1, 2, 3, and 4 h data; and (3) linear interpolation using only 0, 1, 2, and 4 h data., Results: Of 495 patients, 265 had normal GE, 4 rapid GE (<30% retention at 1 h), and 226 delayed GE: 17 delayed only at 2 h (>60% ret); 94 delayed only at 4 h (>10% ret); and 115 delayed at both 2 h and 4 h. Strong correlations were seen between each T ½ method and 1, 2, 3, and 4 h %-empty values: curve-fit T ½ (r = -0.851, -0.942, -0.864, -0.744), linear T ½ using all imaging times (r = -0.848, -0.972, -0.878, -0.763), and linear T ½ using standard imaging times (r = -0.853, -0.974, -0.868, -0.760). The 132 min cutoff for delayed GE captures 99.1% to 100% of delayed GE at both 2 h and 4 h, 76.5% to 94.1% delayed at 2 h only, but only 36.7% to 39.4% delayed at 4 h only; 3.5 to 11.3% of patients with normal GE miscategorized as delayed., Conclusions: GES T ½ correlates more strongly with retention at 2 h than at 4 h. T ½ alone may misclassify patients, particularly those with late-phase (4 h only) delays, reducing its utility for diagnosing gastroparesis., (© 2021 John Wiley & Sons Ltd.)

Background: Dyspeptic symptoms are not well correlated with gastric emptying (GE) results., Aims: To determine (a) prevalence of delayed SB transit (SBT) in patients undergoing GE scintigraphy for symptoms of gastroparesis; (b) symptoms associated with delayed SBT., Methods: Patients with symptoms of gastroparesis underwent combined GE and SBT scintigraphy (GES/SBTS). Patients ingested a mixed solid (S)-liquid (L) meal with egg whites labeled with 500 µCi Tc-99 m sulfur colloid and water with 125 µCi In-111 DTPA. Retained S and L gastric activity and percent of L In-111 activity in terminal ileum (TI) and/or cecum/colon at 6 h were determined. Patient Assessment of Gastrointestinal Symptoms (PAGI-SYM) assessed symptoms from 0 (none) to 5 (very severe)., Key Results: Of 363 patients, 174 (47.9%) had delayed S GE, 141 (38.8%) delayed L GE, and 70 (19.3%) delayed SBT. Delayed SBT was seen in 24 (6.6%) with normal S GE and 46 (12.7%) with delayed S GE. Patients with isolated delayed SBT had highest symptom scores for postprandial fullness (3.5), stomach fullness (3.4), nausea (3.2), bloating (3.2), compared to isolated delayed S GE who had highest symptom scores for postprandial fullness (3.7), nausea (3.6), stomach fullness (3.4), and early satiety (3.3)., Conclusions & Inferences: Delayed SBT occurred in 19.3% of dyspeptic patients using GES/SBTS. While postprandial and stomach fullness were common to both delayed S GE and delayed SBT, early satiety was associated with delayed S GE whereas bloating was associated with delayed SBT. Thus, SBTS can augment GES to help explain some symptoms associated with dyspepsia and suspected gastroparesis., (© 2020 John Wiley & Sons Ltd.)

This article reviews the latest enhancements in standards and technology for performing gastric emptying and associated small bowel and colon transit scintigraphic studies. It discusses how developments in appropriate use criteria, American Medical Association Current Procedural Terminology coding, and advanced commercial software permit clinicians to obtain more comprehensive physiologic studies of gastric, small bowel, and colon gastrointestinal motility disorders. It shows how gastrointestinal scintigraphy has expanded to permit assessments of global and regional (fundic and antral) gastric motility and how it permits a single study (whole-gut transit scintigraphy), including measurement of solid and liquid gastric emptying and small bowel and colon transit., Competing Interests: Disclosure The author has nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Our aim was to investigate the feasibility of measuring antral contractions and duodenal bolus propagation (DBP) during dynamic antral contraction scintigraphy (DACS) as an assessment of antro-pyloro-duodenal coordination (APDC). Gastric emptying scintigraphy (GES) with DACS was performed with Tc-99m sulfur colloid (SC) using increasing doses of 74 MBq (2 mCi) for 10 subjects, 185 MBq (5 mCi) for 11, and 370 MBq (10 mCi) for 11. DACS was performed for 10 min after static images at 0, 30, 60, 120, 180, and 240 min in anterior and right anterior oblique (RAO) projections. Best projection and lowest dose of Tc-99m SC were assessed visually. DBP were quantified utilizing duodenal activity peaks from a region of interest in the first portion of the duodenum. DBP was better visualized in the RAO projection than anterior projection and using 185 MBq (5 mCi) and 370 MBq (10 mCi) compared with 74 MBq (2 mCi). DBP showed infrequent and irregular bolus transfers from the antrum to the duodenum. Antral activity peaks at 60 min averaged 2.91 ± 0.66 per minute and duodenum bolus peaks 0.36 ± 0.18 per minute (ratio 0.36/2.91 = 0.12). DBP activity peaks can be measured during GES with DACS but requires a 185-MBq (5 mCi) dose of Tc-99m SC radiolabeled test meal for adequate DBP signal detection and is better imaged in RAO than anterior projection. DBPs over the first 60 min postmeal ingestion are infrequent with only 12% of the antral contractions propagating into the duodenum. This methodology appears promising to assess APDC. NEW & NOTEWORTHY This study shows that duodenal bolus propagations after meal ingestion can be measured during gastric emptying scintigraphy using dynamic scintigraphy. Duodenal bolus propagation over the first 60 min postmeal ingestion are infrequent with only 12% of the antral contractions propagating into the duodenum. This methodology appears promising to assess antropyloroduodenal coordination in patients with unexplained symptoms of upper gastrointestinal dysmotility.

Management of a patient's blood glucose or metabolism in nuclear medicine studies has become an integral aspect of daily work primarily due to the increasing use of F-18 flurodeoxyglucose (FDG) positron emission tomography (PET). Newer tracers such as F-18 Fluciclovine and C-11 Choline, are in theory subject to metabolic shifts and changes based on patients' insulin levels, and also require attention to achieving optimum patient preparation. Metabolic derangements can also affect other studies, such as gastric emptying (GE), the results of which are dependent upon the patient's blood glucose level during the time of imaging. The growing variety of diabetic medications has increased the complexity of the instructions which need to be given to patients. Current guidelines for patient preparation were developed in the past and have only slowly evolved with the introduction of newer oral medications. In addition to older insulin formulations newer formulations with different profiles of onset, duration, and consistency of action are being used. The wide spectrum of newer drugs now in use for treating diabetes has not been accompanied by any updated consensus on how to manage these drugs for imaging studies which require blood glucose level management. In this article we review these newer diabetes medications primarily to raise awareness of the changing landscape. Our focus will be on suggestions to optimize patient preparation and management for these studies. For each scenario, our suggestions will be given as summary proposals for best patient management. Our hope is that this discussion will stimulate multicenter studies to provide data to support new practice guidelines for metabolically dependent nuclear medicine procedures., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Gastric emptying scintigraphy (GES) as now commonly performed measures only total gastric emptying. Intragastric meal distribution (IMD) immediately after meal ingestion (t = 0 min) (IMD 0 ) can assess fundic accommodation, and dynamic antral contraction scintigraphy (DACS) can assess antral motility. Our goals were to incorporate IMD and DACS into GES, compare IMD 0 using gastric division into anatomic proximal and distal halves versus more physiologic separation of the antrum from the proximal stomach using DACS, and establish reference values. Methods: Healthy subjects ( n = 20) underwent GES using a solid-liquid meal. DACS (1 frame/3 s) was performed for 20 min after each static imaging time. IMD 0 was measured using both semiautomated software to divide the gastric long axis into anatomic halves and Fourier analysis to identify antral pixels with phasic contractions. Results: Using halving of the stomach, IMD 0 averaged 0.75 ± 0.15 (SD). Using phasic contractions to define the antrum, mean IMD 0 was 0.85 ± 0.14 ( P = 0.004). Sustained antral contractions started at a mean of 11.24 ± 12.98 min after meal ingestion and originated in the gastric midbody with a starting location at 40.5% ± 10.8% from the distal to the proximal stomach along its long axis. Antral frequency and ejection fraction peaked 30 min after meal ingestion at 3.30 ± 0.71 contractions per minute and an ejection fraction of 30.3% ± 13.69%, when mean antral filling peaked at 36.7% ± 14%. Maximum antral contraction speed was 3.54 ± 0.90 mm/s at 60 min after meal ingestion. Gastric retention was 39.8% ± 12.8% at 2 h and 5.8% ± 6.0% at 4 h. Conclusion: Addition of DACS to GES permits physiologic characterization of both fundic accommodation and antral contractility to supplement routine GES., (© 2019 by the Society of Nuclear Medicine and Molecular Imaging.)

There is increasing recognition of the importance of assessing patients with unexplained upper gastrointestinal symptoms for impaired gastric accommodation. New therapeutic approaches to treat impaired accommodation are being developed. This increasing interest in diagnosing and treating impaired gastric accommodation emphasizes the need to have a clinically available method to measure the gastric accommodation response. In this editorial, gastric accommodation is discussed along with the currently available methods for its assessment. We summarize our thoughts on what are the next steps needed to make a readily accessible method for assessing gastric accommodation more widely available.

The 2006 National Academy of Sciences Biologic Effects of Ionizing Radiation (BEIR) VII report is a well-recognized and frequently cited source on the legitimacy of the linear no-threshold (LNT) model-a model entailing a linear and causal relationship between ionizing radiation and human cancer risk. Linearity means that all radiation causes cancer and explicitly excludes a threshold below which radiogenic cancer risk disappears. However, the BEIR VII committee has erred in the interpretation of its selected literature; specifically, the in vitro data quoted fail to support LNT. Moreover, in vitro data cannot be considered as definitive proof of cancer development in intact organisms. This review is presented to stimulate a critical reevaluation by a BEIR VIII committee to reassess the validity, and use, of LNT and its derived policies., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

Impaired fundic accommodation (FA) limits fundic relaxation and the ability to act as a reservoir for food. Assessing intragastric meal distribution (IMD) during gastric emptying scintigraphy (GES) allows for a simple measure of FA. The 3 goals of this study were to evaluate trained readers' (nuclear medicine and radiology physicians) visual assessments of FA from solid-meal GES; develop software to quantify GES IMD; and correlate symptoms of gastroparesis with IMD and gastric emptying. Methods: After training to achieve a consensus interpretation of GES FA, 4 readers interpreted FA in 148 GES studies from normal volunteers and patients. Mixture distribution and κ-agreement analyses were used to assess reader consistency and agreement of scoring of FA. Semiautomated software was used to quantify IMD (ratio of gastric counts in the proximal stomach to those in the total stomach) at 0, 1, 2, 3, and 4 h after ingestion of a meal. Receiver-operating-characteristic analysis was performed to optimize the diagnosis of abnormal IMD at 0 min (IMD 0 ) with impaired FA. IMD 0 , GES, water load testing, and symptoms were then compared in 177 patients with symptoms of gastroparesis. Results: Reader pairwise weighted κ-values for the visual assessment of FA averaged 0.43 (moderate agreement) for normal FA versus impaired FA. Readers achieved 84.0% consensus and 85.8% reproducibility in assessing impaired FA. IMD 0 based on the division of the stomach into proximal and distal halves averaged 0.809 (SD, 0.083) for normal FA and 0.447 (SD, 0.132) ( P < 0.01) for impaired FA. On the basis of receiver-operating-characteristic analysis, the optimal cutoff for IMD 0 discrimination of normal FA from impaired FA was 0.568 (sensitivity, 86.7%; specificity, 91.7%). Of 177 patients with symptoms of gastroparesis, 129 (72.9%) had delayed gastric emptying; 25 (14.1%) had abnormal IMD 0 Low IMD 0 (impaired FA) was associated with increased early satiety ( P = 0.02). Conclusion: FA can be assessed visually during routine GES with moderate agreement and high reader consistency. Visual and quantitative assessments of FA during GES can yield additional information on gastric motility to help explain patients' symptoms., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

The Society of Nuclear Medicine and Molecular Imaging and European Association of Nuclear Medicine procedure guide on gastrointestinal transit currently indicates that the mean of total abdominal counts of 7 time points (0-360 min) is used to define the total abdominal counts for bowel transit studies. The purpose of this study was to investigate the variability of total abdominal counts during the initial 6 h of bowel transit and to determine whether a simplified, single-time-point measurement can be used., Methods: Thirty consecutive bowel transit studies were retrospectively analyzed. Patients received an oral dose of 4.6 MBq (125 μCi) of 111 In-DTPA in 300 cc of water together with a standard egg white solid-phase, gastric-emptying meal to measure small bowel and colon transit. 111 In-DTPA geometric mean and decay-corrected total abdominal counts obtained at 0, 30, 60, 120, 180, 240, 300, and 360 min after meal ingestion were analyzed. The coefficient of variation was used to determine the variability of the mean total abdominal counts. Slope of the regression line, Student t test, and a Pearson product-moment correlation coefficient (PCC) were also calculated to determine the correlation of total abdominal counts at each time point compared with the mean of all time points., Results: The mean coefficient of variation of total abdominal counts of each patient was 3.3%, with a range of 1.1%-6.3%. The mean of the slope of the regression line of the total abdominal counts of the patients was -0.001 ± 0.003. There was no significant difference between the measured slope of the regression line compared with a line with a slope of 0 (P > 0.05). When the counts at each time were compared with the mean counts, there was no significant difference (P > 0.05). The PCC of each of the counts showed a significant and strong correlation between each interval and the mean total abdominal counts (P < 0.01)., Conclusion: There is no significant variability in geometric mean 111 In-DTPA total abdominal counts during the initial 6 h of bowel transit studies. This can permit a more simplified analysis using the total abdominal counts from only a single time point., (© 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Although not as well standardized as gastric emptying (GE) scintigraphy, esophageal transit scintigraphy, if performed in a comprehensive manner including both quantitative and qualitative analysis of single- and multiple-swallow studies, is clinically useful when expertise in esophageal manometry is not available or not tolerated and when esophageal manometry or barium videofluoroscopy results are equivocal or nondiagnostic. GE scintigraphy has undergone much-needed standardization. Both solid and liquid GE studies play an important role in assessing patients with upper gastrointestinal symptoms. Because measurement of simple total GE is often not sufficient to explain patient symptoms, there is a need to expand the analysis of GE scintigraphy to include the separate roles of the fundus and antrum and to include the complex interactions the stomach has with other organ systems., (© 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Because of the difficulty often encountered in deciding whether a patient's symptoms originate in the upper or lower gastrointestinal tract, gastrointestinal transit scintigraphy is a uniquely suited noninvasive, quantitative, and physiologic method of determining whether there is a motility disorder affecting the stomach, small bowel, or colon. Small-bowel and colon transit studies can be performed alone or together with gastric emptying studies after oral administration of an appropriately radiolabeled meal. It is hoped that newly published standards for performing these studies and the anticipated arrival of new Current Procedural Terminology codes in the United States for small-bowel and colon transit studies will increase their availability and use., (© 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Because of the difficulty often encountered in deciding whether a patient's symptoms originate in the upper or lower gastrointestinal tract, gastrointestinal transit scintigraphy is a uniquely suited noninvasive, quantitative, and physiologic method of determining whether there is a motility disorder affecting the stomach, small bowel, or colon. Small-bowel and colon transit studies can be performed alone or together with gastric emptying studies after oral administration of an appropriately radiolabeled meal. It is hoped that newly published standards for performing these studies and the anticipated arrival of new Current Procedural Terminology codes in the United States for small-bowel and colon transit studies will increase their availability and use., (© 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Although not as well standardized as gastric emptying (GE) scintigraphy, esophageal transit scintigraphy, if performed in a comprehensive manner including both quantitative and qualitative analysis of single- and multiple-swallow studies, is clinically useful when expertise in esophageal manometry is not available or not tolerated and when esophageal manometry or barium videofluoroscopy results are equivocal or nondiagnostic. GE scintigraphy has undergone much-needed standardization. Both solid and liquid GE studies play an important role in assessing patients with upper gastrointestinal symptoms. Because measurement of simple total GE is often not sufficient to explain patient symptoms, there is a need to expand the analysis of GE scintigraphy to include the separate roles of the fundus and antrum and to include the complex interactions the stomach has with other organ systems., (© 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Folate receptor (FR) can be used as a therapeutic target because of its expression on different epithelial cancers, such as ovarian, non-small cell lung, endometrial, and breast cancer. Assessing FR expression in tumors may help to identify patients who can benefit from FR-targeted therapeutics, such as vintafolide and farletuzumab. Different methods exist to detect FR expression. Tissue sampling has limited clinical utility, mainly because it requires an invasive procedure. (99m)Tc-etarfolatide, a (99m)Tc-labeled folate conjugate, is in late-phase trials in Europe and the United States. It allows noninvasive, whole-body imaging of the FR. This review focuses on this FR-imaging agent and how it may be used to direct FR-targeted therapy.

Background: This report examines (99m)Tc-etarfolatide imaging to identify the presence of folate receptor (FR) on tumors of women with recurrent/refractory ovarian or endometrial cancer and correlates expression with response to FR-targeted therapy (vintafolide)., Patients and Methods: In this phase II, single-arm, multicenter study, patients with advanced ovarian cancer were imaged with (99m)Tc-etarfolatide before vintafolide treatment. Up to 10 target lesions (TLs) were selected based on Response Evaluation Criteria In Solid Tumors criteria using computed tomography scans. Single-photon emission computed tomography images of TLs were assessed for (99m)Tc-etarfolatide uptake as either FR positive or negative. Patients were categorized by percentage of TLs positive and grouped as FR(100%), FR(10%-90%), and FR(0%). Lesion and patient response were correlated with etarfolatide uptake., Results: Forty-nine patients were enrolled; 43 were available for analysis. One hundred thirty-nine lesions were (99m)Tc-etarfolatide evaluable: 110 FR positive and 29 FR negative. Lesion disease control rate (DCR = stable or response) was observed in 56.4% of FR-positive lesions versus 20.7% of FR-negative lesions (P < 0.001). Patient DCR was 57%, 36%, and 33% in FR(100%), FR(10%-90%), and FR(0%) patients, respectively. Median overall survival was 14.6, 9.6, and 3.0 months in FR(100%), FR(10%-90%), and FR(0%) patients, respectively., Conclusions: Overall response to FR-targeted therapy and DCR correlate with FR positivity demonstrated by (99m)Tc-etarfolatide imaging., Clinical Trial Number: NCT00507741.

Background: Gastric emptying scintigraphy (GES) using a solid meal is often recommended for the evaluation of gastroparesis. However, some patients cannot tolerate the standardized egg-white sandwich (EWS) solid meal and an alternative meal is needed., Aim: The aim of this study was to compare GES, regional gastric emptying, and gastric contractility using a liquid nutrient meal (LNM; Ensure Plus(®)) to those using EWS., Methods: Twenty healthy volunteers underwent GES using EWS and LNM on separate days. Gastric emptying was measured using scintigraphy and with a wireless motility capsule (WMC; SmartPill(®))., Results: The gastric emptying half-time with LNM was similar to that with EWS (1.41 ± 0.11 vs 1.52 ± 0.08 h; P = 0.28) and the two were significantly correlated (r = 0.53; P = 0.017). There were time-related differences in gastric emptying of the LNM compared to EWS: in the first hour, gastric retention of EWS was slightly greater than that of LNM, whereas at 3 and 4 h, gastric retention of EWS was slightly less than that of LNM. Regionally, the percentage retention of the meal in the proximal stomach was greater for EWS than for LNM at 0.5 h. WMC gastric emptying times and gastric contractility for the two meals were not significantly different., Conclusions: Overall gastric emptying of the LNM was similar to that of the EWS meal. The LNM empties without a lag phase and takes slightly longer to empty from the distal stomach, likely due to its higher fat content. These differences are likely due to early accommodation with retention of solids in the proximal stomach and the need for trituration of solids. We conclude that this LNM can serve as an alternative to the conventional solid EWS for GES.

For many years, gastric emptying (GE) studies were performed using various local protocols and different radiolabeled meals. This lack of standardization and normal values made the test results unreliable and difficult to compare from one site to another. A recent consensus has been published that now provides guidance and standardization on how to perform a radiolabeled solid-meal GE study. It is widely recognized, however, that simple measurement of total GE of a solid meal often does not provide an answer to the etiology of symptoms for a large number of patients who present with functional dyspepsia. Advances in our understanding of the different roles of the fundus and antrum and their complex interaction with the proximal small bowel and central nervous system have led to the development of new methods to study gastric motility. This review describes how a more comprehensive approach to studying GE is needed and how this will lead to better diagnosis and treatment for patients referred for GE studies., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background and Aims: Cholecystokinin-cholescintigraphy (CCK-CS) provides a physiologic, noninvasive, and quantitative method for assessing gallbladder contraction and calculation of a gallbladder ejection fraction (GBEF). At present, it is used most commonly to identify patients with suspected functional gallbladder disorder. However, the methodology of CCK infusion and normal values differ markedly among imaging centers., Methods: This document represents the consensus opinion of an interdisciplinary panel that gathered to assess the current optimal method for performing CCK-CS in adults, potential uses and limitations of CCK-CS, and questions that require further investigation., Results: The panel recommended the use of a single, standardized, recently described CCK-CS protocol that involves infusion of 0.02 μg/kg of sincalide over 60 minutes with a normal GBEF defined as ≥38%. The panel emphasized the need for a large, multicenter, prospective clinical trial to establish the utility of CCK-CS in the diagnosis of functional gallbladder disease. Although not without controversy regarding its clinical utility, the primary indication for CCK-CS at present is the well-selected patient with suspected functional gallbladder disorder., Conclusion: Agreement was reached that the adoption of this standardized protocol is critical to improve how CCK-CS is used to direct patient care and will represent an improvement over the diverse methods currently in use by eliminating the current lack of uniformity and adding both reliability and credibility to the results.