Radionuclide Gastric Emptying Studies Research Articles

Change in Management After Radionuclide Gastric Emptying Studies Showing Slow Emptying.

The radionuclide gastric emptying study is the gold standard for the diagnosis of gastroparesis. Methods: We performed a retrospective analysis of 510 patients to evaluate how often a diagnosis of slow gastric emptying determined by gastric emptying scintigraphy (GES) changes clinical management at our institution. Results: We found evidence of gastroparesis in 100 patients. A change in management was recommended for 62% within 1 mo of the GES. Conclusion: Our results illustrate the importance of performing GES on patients with clinically suspected gastroparesis.

Mo1316 Two Hour Gastric Emptying Radionuclide Scintigraphy is Associated With False Diagnosis of Gastroparesis in Children

Introduction: Gastroparesis is a rare motor and sensory disorder of the stomach resulting in delayed gastric emptying in the absence of mechanical obstruction. Symptoms include nausea, vomiting, early satiety, bloating, abdominal pain, and weight loss. There is a paucity of data about the prevalence and etiology of gastroparesis in children, but the most common etiologies are post-viral, idiopathic and autonomic dysfunction disorders. Four hour radionuclide scintigraphic gastric emptying (GE) study is the recommended diagnostic study for gastroparesis. Many centers perform only a 2 hour GE study. There have been no comparison studies between these twomethods in pediatric patients. Methods:We conducted a retrospective review of the Mayo Clinic electronic data between April 2005 and June 2013. All children age (0-18) years diagnosed with gastroparesis, who underwent a 2 hour GE study, followed by 4 hour GE study were included. Children with history of gastric surgery (including gastric neurostimulator devices), diabetes, or on prokinetic medications were excluded. GE study was considered abnormal when GE was less than 7% at 1 hour, 31% at 2 hours and 81% at 4 hours. All demographic, symptoms and GE test results were recorded. This study was approved by the Mayo Clinic IRB. Results: A total 13 children (7 females, average age of 12 years) were identified. The most common reported symptoms at the time of both studies were abdominal pain (63%), nausea/ vomiting (38%), and bloating/ abdominal distention (16%). Many patients had multiple symptoms. Eighty five percent (n= 11) patients were diagnosed with gastroparesis using the 2 hour GE study. Out of 11 patients only 2 (18%) were confirmed with gastroparesis on the subsequent 4 hour GE study. Median time between the two studies was 6 months. None of the patients who had normal 2 hour study had an abnormal 4 hour study. Discussion: All patients who were diagnosed with gastroparesis by the 2 hours GE study continued to have symptoms despite trying different medications and diet modifications. Patients discontinued any prokinetic medications before repeating a 4 hour GE study. Most of the patients (85%) had a normal 4 hour GE study, despite persistence of their symptoms. These patients could have had GI symptoms due to a different etiology such as functional or other motility disorders (impaired accommodation). The improved GE results could be due to regression toward the mean, or true improvement in the gastric emptying function during the time elapsed between the two studies. Conclusion: The 2 hour radionuclide scintigraphic GE test is unreliable, and can result in false diagnosis of gastroparesis in children. Four hour GE radionuclide scintigraphy testing should be the standard practice.

Liquid Gastric Emptying is Often Abnormal When Solid Emptying is Normal

The medical literature states that solid radionuclide gastric emptying studies are more sensitive than liquid studies for detection of gastroparesis and thus liquid studies are rarely indicated. At our institution, patients are often referred for both studies. Our initial purpose was to review the results in those patients. The surprising results led us to initiate a prospective investigation to more directly determine the relative value of solid versus liquid emptying studies. The retrospective review included 21 patients who had both studies performed on separate days. The subsequent prospective investigation was initiated so that the solid and liquid emptying studies were acquired sequentially on the same day. A total of 40 consecutive patients with symptoms suggestive of gastroparesis (mean age 44.8, 12 males, 28 females) were investigated. All ingested 300 mL water with radiotracer and were imaged each minute 30. They then ingested the radiolabeled solid meal and were imaged each hour 4. A liquid emptying rate (T1/2) and solid percent emptying each hour 4 was determined. In the retrospective review, 17 of 21 patients had normal solid emptying; of those, 13 had delayed liquid emptying. In the subsequent prospective study, 30/40 (75%) had normal solid emptying; of those, 10 (33%) had delayed liquid emptying. Nine patients (23%) had delayed solid emptying; 13 (32%) had delayed liquid emptying. Liquid gastric emptying is commonly abnormal in patients who have normal solid studies. Liquid studies should be routinely performed in addition to solid studies to fully evaluate gastric motility in patients with symptoms suggestive of gastroparesis.

False Negative Test for Gastropresis from Technicium (Tc) Oatmeal Radionuclide Gastric Emptying (GE) Study; Lack of Standardized Updated Protocols for Tc GE in Community Hospitals

False Negative Test for Gastropresis from Technicium (Tc) Oatmeal Radionuclide Gastric Emptying (GE) Study; Lack of Standardized Updated Protocols for Tc GE in Community Hospitals

Preoperative gastric emptying and patterns of reflux as predictors of outcome after laparoscopic fundoplication

Some studies have suggested that patients with predominantly upright reflux have a poor outcome after laparoscopic antireflux surgery. It has been proposed that this might be related to gastric emptying. The aim of this study was to evaluate the relationship between preoperative upright reflux pattern, gastric emptying rate and outcome after laparoscopic fundoplication. Patients presenting for antireflux surgery underwent 24-h ambulatory pH testing and dual-isotope radionuclide gastric emptying studies. Reflux pattern was determined by the acid exposure in the distal oesophagus (percentage of time at pH < 4) during supine and upright posture. Outcome after fundoplication was assessed by a standardized postal questionnaire administered at 3 months, and 1, 2 and 5 years after surgery. Of 372 patients identified from a prospectively maintained database, 109 had upright reflux, 57 supine reflux and 206 bipositional reflux. Overall patient satisfaction was not influenced by reflux pattern at any time after surgery. Delayed gastric emptying was documented in 31.0 per cent of patients, but there was no relationship with reflux pattern. Patients with upright reflux did not have a less favourable outcome after fundoplication. Categorizing patients according to reflux pattern is of no value in predicting outcome or selecting patients for surgery.

Effect of hypo- and hyperthyroidism on gastric myoelectrical activity.

Although hypo- and hyperthyroid patients have different symptoms in the gastrointestinal tract, the mechanism of thyroid action on the gut remains poorly understood. Thus the aim of this study was to investigate the effect of hypo- and hyperthyroidism on gastric myoelectrical activity, gastric emptying, dyspeptic symptoms. Twenty-two hyperthyroid (median age 45, 15 females) and 11 hypothyroid (median age 42, 10 females) patients were included into the study. Dyspepsia score, hypo- and hyperthyroid symptom scale, abdominal ultrasonography and upper gastrointestinal endoscopy were performed. Gastric myoelectrical activity was measured by electrogastrograpy (EGG) before and after therapy both preprandially and postprandially and compared with age, gender, and body-matched controls (12 for hypothyroid, 15 for hyperthyroid patients). Radionuclide gastric emptying studies were performed with a solid meal. Hypothyroid patients revealed a significant increase in preprandial tachygastria as compared with controls (12.3% vs 4.8%). The percentage of preprandial normal slow waves (2.4-3.7 cpm) was below 70% (dysmotility) in 7 of 11 hypothyroid patients versus 2 of 12 controls (P < 0.05). Hyperthyroid patients revealed a significantly higher preprandial (3.1 vs 2.8) and postprandial (3.4 vs 3) DF when compared with the controls (P < 0.05). A higher percentage of postprandial taschygastria (7.9 vs 0) was present in hyperthyroid patients than in the controls (P < 0.05). The decrease on postprandial EGG power (power ratio < 1) was observed in 7 patients the in hyperthyroid group and 1 in controls (P < 0.05). The percentage of postprandial normal slow waves was below 70% in 10 of 20 hyperthyroid patients vs 1 of 15 controls (P < 0.05). After therapy these differences disappeared in the euthyroid state. The hypo- and hyperthyroid symptom scale correlated to dyspepsia score. Dyspepsia score in hyperthyroidism correlated to power ratios in hyperthyroid patients. We detected some correlations between serum levels of fT3 or fT4 and some EGG parameters in hypo- and hyperthyroidism. Dyspepsia score and hypo- and hyperthyroid symptom scale were improved significantly after therapy in the euthyroid state. In conclusions, we showed gastric dysrhythmia by EGG in both hypo- and hyperthyroid patients. Dyspeptic symptoms correlated to the activity of thyroid disease. After therapy, these findings and dyspeptic symptoms improved in the euthyroid state. Abnormalities of power ratios may be responsible of dyspeptic symptoms in hyperthyroid patients. EGG may be a useful and noninvasive tool for detecting gastric disturbances during hypo- and hyperthyroidism.

Characterization and management of paraesophageal hernias in children after antireflux operation

Purpose: The aim of this study was to determine the important factors in the development and subsequent treatment of postoperative paraesophageal hernia (PPEH). Methods: A retrospective analysis was performed in 464 consecutive children (ages 3 days to 18 years) for PPEH after a primary antireflux operation performed at a Children's Hospital and University Hospital between 1985 and 1997. All operations included a crural repair, but the Nissen fundoplication was performed with (n = 162) and without (n = 70) plication of the esophagus to the crus at 3 points. Patients with and without PPEH were compared with respect to the type of antireflux operation, the patient's age at operation, and the preoperative and postoperative clinical courses. A preoperative corrected gastric emptying value was obtained from a radionuclide gastric emptying study in 289 patients. The treatment of PPEH also was examined. Results: The incidence of PPEH in our patients was 4.5% (21 of 464). Although there was a lower incidence of PPEH in patients with crural plication compared with patients without crural plication during Nissen fundoplication (5 of 162, 3% v 7 of 70, 10%; P = .035), 2 patients with crural plication had a postoperative esophageal leak. Patients with PPEH had a significantly increased prevalence of gagging before the initial antireflux operation compared with patients without PPEH (3 of 21, 14.3% v 7 of 443, 1.6%; P = .007). A higher prevalence of slow corrected gastric emptying preoperatively also was seen in patients with PPEH compared with patients without PPEH (8 of 15, 53% v 79 of 274, 29%; P = .046). The prevalences of central nervous system disease, young age (<6 months) at initial operation, and a particular type of antireflux operation were not higher in patients with PPEH. Nine patients with a small PPEH treated by simple observation alone subsequently had resolution of symptoms. Conclusions: Patients who have gagging or slow corrected gastric emptying before an antireflux operation are at higher risk for a postoperative paraesophageal hernia. Patients with a small postoperative paraesophageal hernia can be treated nonoperatively. Crural plication of the esophagus during Nissen fundoplication reduces the occurrence of postoperative paraesophageal hernia, but also may result in significant morbidity.

Gastrointestinal symptoms and delayed gastric emptying in Fabry's disease: response to metoclopramide.

The pathophysiology of gastrointestinal symptoms in patients with Fabry's disease is uncertain, despite the demonstration of histological and radiographic abnormalities of the gastrointestinal tract. The aims of this study were to determine if the gastrointestinal symptoms reported by patients with Fabry's disease are associated with abnormal gastric emptying and, if they are, whether prokinetic drug therapy would be beneficial. Ten patients with Fabry's disease had radionuclide gastric emptying studies performed to determine if gastrointestinal symptoms correlated with objective evidence of abnormal gastric emptying. A second study was performed in seven patients who received 5 days of therapy with oral metoclopramide. The mean percent solid gastric emptying for Fabry's patients was significantly less than that of a normal control group (40 vs 67%, P < 0.005). Five of seven patients with symptoms had abnormal gastric emptying. Six of seven symptomatic patients reported clinical improvement with metoclopramide. Of four symptomatic patients who had a repeat study after treatment, two showed improved emptying. In conclusion, our results suggest that gastrointestinal symptoms in Fabry's disease are frequently associated with delayed gastric emptying and that treatment with metoclopramide produces symptomatic and sometimes functional improvement.

A comparison of three gastric lavage methods using the radionuclide gastric emptying study

To determine the percentage of liquid gastric contents experimentally removable by available orogastric lavage systems, five healthy young volunteers were asked to ingest 1 mCi of liquid technicium-99m diethylenetriaminepentaacetic acid (Tc 99m-DTPA) mixed with 50 ml tap water. Five minutes afterwards, the radionuclide was lavaged using one of three different techniques—a single syringe method, a closed gravity drainage system, and a closed double syringe method—while continuous radioisotope camera images were taken. Control images, with no lavage performed, were also taken. All of the orogastric lavage methods removed a mean of between 80% and 85% of the stomach contents. The double syringe method was the quickest, while the single syringe method was least tolerated. When compared with control, none of the lavage techniques pushed gastric contents into the duodenum. Thus, in terms of amount of liquid gastric contents removed, there was no one method that removed more than the others. Caution should be exercised in assuming that 80–85% of a liquid gastric ingestion can be removed by lavage in the uncontolled clinical setting. The use of any orogastric lavage for ingestion evacuation should be undertaken knowing that it is a morbid procedure and usually not necessary.

Influence of meal energy on gastric emptying in healthy Chinese.

Radionuclide gastric emptying studies of liquid phases were used to evaluate the gastric motility of healthy Chinese. A total of 53 normal volunteers were included in this study and divided into two groups. Group 1, included 20 males and 8 females (ages: 17-73) who received a meal which consisted of 500ml normal saline containing 500 uCi of Tc-99m phytate. Group 2, included 19 males and 6 females (ages: 27-73) who received a meal which consisted of 500ml 5% glucose solution (25g glucose, 100Kcal) labeled with 500 uCi Tc-99m phytate. Studies were performed with the subjects in the supine position and a gamma camera in a left anterior oblique (LAO) position, while data were collected for 30 minutes after injection of the liquid meal. The gastric emptying time was presented as the half-time (T1/2) for the food to empty from the stomach. The study results showed that the T1/2 was 20.5 +/- 7.2 min in Group 1 and 35.3 +/- 11.7 min in Group 2. We conclude that gastric emptying is slower for a liquid meal with a higher caloric content.

Influence of Age on Gastric Emptying in Healthy Chinese

Radionuclide gastric emptying studies, including solid and liquid phases, were used to evaluate the gastric motility of healthy Chinese. Forty-eight patients (18-76 years old) and 38 volunteers (27-79 years old) accepted solid or liquid food gastric emptying studies, respectively. The solid meal was two fried eggs mixed with 500 microCi Tc-99m phytate and two pieces of toast to form a sandwich. The liquid meal was 500 ml of water with 5% glucose and 500 microCi Tc-99m phytate. Studies were performed with the subjects in the supine position and a gamma camera in a left anterior oblique (LAO) position while data were collected for 90 minutes and 30 minutes after finishing the solid and liquid meal, respectively. The gastric emptying time was presented as a half-time (t1/2) of the food emptying from the stomach. The study results showed that the t1/2 is 89.0 +/- 17.8 in older patients (> 60 years old) and 88.0 +/- 18.2 in younger patients (< or = 60 years old) for the solid phase studies (P > 0.05), and that the t1/2 is 46.2 +/- 11.1 in older patients (> 60 years old) and 31.9 +/- 11.3 in younger patients (< or = 60 years old) for the liquid phase studies (P < 0.05). We concluded that the age effects of gastric emptying in healthy Chinese occurred only in the liquid phase.

Diabetic gastroparesis.

Preview As many as 30% of patients with long-standing diabetes mellitus may have symptoms of gastroparesis, and others are found to have the condition despite being asymptomatic. When should diabetic gastroparesis be suspected, and which are the best tests for detecting it? What factors can exacerbate it? Drs Clark and Nowak address these questions and discuss the therapeutic value of dietary modification, pro- kinetic agents, and surgical intervention.

Gastric emptying in patients with chronic renal failure on continuous ambulatory peritoneal dialysis

Radionuclide gastric emptying studies were carried out on 20 patients with end-stage renal failure (ESRF) undergoing continuous ambulatory peritoneal dialysis (CAPD). Nine of the patients had diabetes mellitus. Eight normal volunteers were also studied to establish normal ranges. Solid and liquid emptying patterns were investigated simultaneously using a meal made up of a solid phase labelled with 99mTechnetium and a liquid phase labelled with 111Indium. The solid emptying fitted a model with a lag phase followed by a linear emptying phase and the liquid emptying fitted a single exponential. Nine of the 20 patients (four diabetic, five non-diabetic) were found to have delayed solid emptying, and four of these (two diabetic, two non-diabetic) also had delayed liquid emptying. No correlation was found between any of the parameters studied and the clinical symptoms of the patients. It is concluded that almost half of the patients studied had abnormal gastric emptying, but that many of these did not suffer from severe symptoms.

Electrogastrography in patients with gastroparesis and effect of long-term cisapride.

Abnormalities in the gastric pacemaker potentials occur in patients with impaired gastric emptying. It is unclear if treatment effects the underlying rhythm or if normalization of dysrhythmias is important. We examined the effect of cisapride using surface electrogastrograms and radionuclide gastric emptying studies of patients with idiopathic and diabetic gastroparesis. Twelve of 14 patients had abnormal baseline electrogastrograms. After six months of cisapride, four patients had normalization of their electrical activity and six had improvement. Patients with idiopathic gastroparesis had an increase in gastric emptying at 120 min from 48.9 +/- 3.8% (baseline) to 70.9 +/- 6.0% (six months), P = 0.009. Patients with diabetes mellitus had a similar improvement. Patients who had normalization of the electrogastrogram had a greater gastric emptying rate than patients with continued dysrhythmias. Thus, dysrhythmias are important in the etiology for gastroparesis, but other factors need to be examined.

Cytomegalovirus infection and gastric emptying.

Gastrointestinal infection due to cytomegalovirus occurs frequently in liver transplant recipients. Upper gastrointestinal cytomegalovirus infection is associated with subjective complaints of nausea, a sense of abdominal fullness, and occasionally emesis and/or dysphagia. In order to determine whether these symptoms reflect a disruption of the normal motility of the stomach, the following study was performed. Eleven individuals who were evaluated for liver transplantation were prospectively recruited and studied as follows: (1) upper gastrointestinal endoscopy with biopsy of the gastric antral mucosa; (2) viral culture of the gastric mucosa; (3) a histologic examination of the gastric mucosa; and (4) a radionuclide gastric emptying study was obtained before and 4-8 weeks following successful liver transplantation. Prior to liver transplantation, none had symptoms of nausea, vomiting, or epigastric fullness. All were culture-negative for cytomegalovirus. All had endoscopic and histologic evidence of portal hypertensive gastropathy but none had antral erosions or ulcers. All demonstrated normal gastric emptying of a liquid meal. Following liver transplantation, 6 remained free of gastric cytomegalovirus while 5 developed a culture-confirmed gastric cytomegalovirus infection. Those that developed a gastric cytomegalovirus infection also had more gastric symptoms, and more gastric histologic abnormalities. Moreover, those with a gastric cytomegalovirus infection demonstrated enhanced gastric retention of a liquid meal (P less than 0.01).

Continuous gastric pH monitoring in children: The effect of gastric emptying on the measurement of gastric acid secretion

Continuous gastric pH monitoring offers the opportunity to evaluate gastric acid secretion in humans without the need for collection of gastric aspirates. However, gastric emptying may be an important variable for the accurate measurement of gastric acid secretion using continuous gastric pH monitoring. We conducted an in vitro study (phase I) to evaluate the effect of gastric emptying on gastric pH. The in vitro study used a laboratory model in which continuous pH monitoring of a standard formula (Nutramigen, 100 mL) in a reservoir was performed while varying both the reservoir emptying rate (10% to 80%) over 1 hour and the amount of added acid (2 to 15 mEq/h: in vivo equivalent of 6 to 45 mEq/m2 BSA/h). An in vivo study (phase II) was then performed in 28 infants less than 6 months of age who had gastroesophageal reflux (GER) documented by 18- to 24-hour esophageal pH monitoring. At the end of esophageal pH monitoring, the pH electrode was advanced into the stomach for measurement of gastric pH continuously for 2 hours after a feeding of Nutramigen formula (300 mL/m2 BSA). Each patient also had a radionuclide gastric emptying study performed with the same volume of Nutramigen formula. In the in vitro model, the reservoir pH (% time pH less than 4) was proportional to the reservoir emptying rate only when acid was added at less than 15 mEq/h (less than 45 mEq/m2 BSA/h). Reservoir pH was independent of reservoir emptying rate when acid was added at 15 mEq/h (45 mEq/m2 BSA/h).(ABSTRACT TRUNCATED AT 250 WORDS)

Antroduodenal manometry

We performed fasting and postprandial recordings of antroduodenal manometry in 21 normal volunteers, 13 patients with insulin-dependent diabetes mellitus and gastrointestinal symptoms, and 11 patients with the irritable bowel syndrome. None of the patients or volunteers had previously undergone an intestinal intubation study. Recordings could not be obtained from four of the diabetic patients due to failure to intubate the pylorus. Catheter migration led to incomplete antral data in a further 21% of all recordings. Due to the wide variations demonstrated by the normal volunteers, parameters of either the migrating motor complex (MMC) or the fed response could not differentiate between either of the patient groups and/or the controls. Similarly, while abnormal patterns of either fasting or postprandial motility were common in the diabetic patients, manometry had a sensitivity of only 67% in comparison to the less invasive radionuclide gastric emptying study. Furthermore, manometry failed to identify any diagnostic abnormality in irritable bowel patients; in particular, the incidence of "clustered" contractions was similar in all three groups. We conclude that short duration antroduodenal manometry is of limited diagnostic usefulness due to the difficulties in pyloric intubation in the presence of a dilated stomach and the intrinsic variability in normal motor patterns, perhaps excerbated by the stressful effects of the procedure itself in tube-naive subjects.

Effect of mild mental stress on solid phase gastric emptying in healthy subjects

Radionuclide gastric emptying studies are performed in clinical routine but the possible influence of the mental state of the patient is never taken into account. We wanted to evaluate the effect of a mild psychological stress on solid phase gastric emptying in healthy young male volunteers. The standard meal consisted of a pancake (500 kJ) without additional liquid. Simultaneous dynamic acquisitions of gastric activity in anterior and posterior projection were taken during 90 min starting from the onset of the meal. Gastric emptying was evaluated three times in basal conditions and once under mental stress. Stress was induced by means of a dichotomous listening test, lasting for 30 min, starting at the end of the meal. The results of rest and stress studies were compared. Mild mental stress has a significant influence on gastric emptying. The lag phase increased from 11 +/- 3 min to 36 +/- 10 min (mean +/- S.D.) (p less than 0.005) and the gastric emptying rate from 79 +/- 13%/hour to 100 +/- 31%/hour (mean +/- S.D.) (not significant). During a stress period gastric emptying as a whole is delayed but this is mainly due to the prolongation of the lag phase. Our data also suggest that during the stress period gastric emptying is interrupted and reactivated once the stress period has ended.

Evaluation of reproducibility of solid-phase gastric emptying in healthy subjects

Radionuclide gastric emptying studies are performed as a matter of clinical routine. Our aim was to evaluate the inter- and intra-individual variability and the reproducibility of gastric emptying studies in healthy young male volunteers using a single solid-phase, standard meal. The meal consisted of a pancake (500 KJ) tagged with technetium 99m sulphur colloid and no additional liquid. Continuous acquisitions of gastric activity in anterior projection were taken during 90 min, starting from the onset of the meal. Gastric emptying was evaluated three times in a 3-week period. Five different parameters were evaluated. Our results show that there is important inter- and intra-individual variability in normal volunteers. In spite of this variability, no significant difference between the different series of gastric emptying studies was observed.

Gastric emptying in marathon runners.

Radionuclide gastric emptying studies using 99m-Tc human serum albumin egg omelette have been carried out in 10 long distance runners at rest and during a 90 minute run at sustained speed. Resting values are compared with controls comprising 10 sedentary subjects. Runners show a significantly accelerated basal gastric emptying (runners t 1/2 = 67.7 (5.9) min; sedentaries t 1/2 = 85.3 (4.5) min, p less than 0.001). The exercise had no significant effect on gastric emptying in these trained subjects (exercise t 1/2 = 66.8 (5.9) min, p = NS), suggesting adaptation to exercise.