The design of a two-phase radiolabelled meal for gastric emptying studies

A meal intended for use in gastric emptying studies must be highly reproducible, must provide a normal physiological stimulus in terms of bulk, calorie content and composition and must employ stable radiotracers which accurately reflect in their biodistribution, the fate of the two phases. This is particularly important in a field, such as gastric emptying, where so many variables may influence the results. A conventional pancake and orange juice were chosen as suitable vehicles for the solid and liquid phases. 111In-labelled resin beads were used as the solid-phase marker and a variety of 99Tcm-labelled radiopharmaceuticals including pertechnetate, DTPA and colloid forms were investigated as liquid-phase markers. Prior to administration to patients, the stability of the phases and their interactions in vitro were investigated. The use of 99Tcm-DTPA resulted in a loss of 111In from solid to liquid phase. All non-colloidal markers exhibited a tendency for adsorption onto solid phase. Colloidal markers including rhenium and antimony sulphide colloids showed the truest delineation of the liquid phase.     

The effect of minor gastric surgery on gastric emptying in the rat.

A new minimally invasive technique has recently been described which enables gastric emptying to be assessed on repeated occasions without the need for animal sacrifice. This technique has been applied to study the effect of a laparotomy or gastrotomy on gastric emptying in the rat. Groups of 10 animals underwent either a laparotomy or a gastrotomy, or were unoperated controls. Solid and liquid gastric emptying studies were performed preoperatively, and for two postoperative months. Emptying was unchanged in unoperated controls. Laparotomy animals showed delayed emptying of both solids and liquids, returning to normal by two months. Gastrotomy animals showed a similar delay in solid emptying, but liquid emptying was within the normal range postoperatively. It is concluded that minor abdominal surgery causes marked alteration in gastric emptying. The comparable emptying delay for patients is unknown, but this should be considered when patients are recovering from operation, and when interpreting postoperative gastric emptying studies.     

液体试餐核素胃排空显像对糖尿病患者胃排空功能的研究

目的应用放射性核素标记的液体试餐行改良的胃排空显像,选择最佳检查体位及胃排空功能评价指标;进而评估糖尿病患者胃轻瘫发生率,并为其诊断及严重程度分级提供依据。 方法55名健康志愿者（对照组）和100例2型糖尿病患者（试验组）分别口服99Tcm-DTPA液体试餐后,即刻应用SPECT仪同时行平卧前位、平卧后位动态显像。影像采集结束后,勾画胃区ROI,经计算机处理后获得时间-放射性曲线,分别计算平卧前位、平卧后位胃半排空时间（GET_1/2）及30 min胃排空率（GER_30min）。3 d后服用同等量放射性核素液体试餐后行坐立后位胃排空动态显像,数据采集及处理方式同前。在此基础上,进一步对正常对照组及试验组胃排空显像数据进行t检验。 结果正常对照组平卧前位GET_1/2为（12.76±2.22）min,其95%置信区间上限为17.1 min（可作为胃排空功能减退的判断标准）。对照组平卧前位和平卧后位、平卧后位和坐立后位GET_1/2及GER_30min比较,差异均有统计学意义（t=5.35、11.20、-6.37、-9.77,均P < 0.01）;对照组和试验组、试验1组（无消化系统症状糖尿病患者组）和试验2组（有消化系统症状糖尿病患者组）平卧前位GER_30min比较,差异均有统计学意义（t=6.22、3.01,均P < 0.01）,其中试验组平卧前位GER_30min较对照组小,试验2组平卧前位GER_30min较试验1组小。统计试验组GET_1/2,41%胃排空功能减退,其中,9%胃排空功能重度受损。 结论液体试餐核素胃排空显像是一种简单易行、准确可靠的胃排空功能检测方法。GET_1/2和GER_30min可作为胃排空功能减退程度的指标,并优选平卧前位进行检查,可在临床推广应用。     

胃排空动态显像中双核素标准餐的应用

目的研究１３１Ｉ小牛血清白蛋白（ＢＳＡ）和９９ｍＴｃＤＴＰＡ双核素胃排空动态显像的方法及探讨其临床应用价值。方法用前临时标记１３１ＩＢＳＡ和９９ｍＴｃＤＴＰＡ，配成１３１ＩＢＳＡ鸡蛋固体餐和９９ｍＴｃＤＴＰＡ水液体餐。固体餐经人胃液消化试验，检测标记物稳定性。检查３５例慢性胃炎病人和１０例健康志愿者的胃排空功能，其中２例在３天内进行了１３１ＩＢＳＡ鸡蛋餐和９９ｍＴｃ硫胶体（Ｓｃ）鸡肝餐两法对照，比较其相关性。结果１３１ＩＢＳＡ和９９ｍＴｃＳｃ在胃液中消化２小时，脱标率分别为３００％和５１６％；１３１ＩＢＳＡ鸡蛋餐法和９９ｍＴｃＳｃ鸡肝餐法相关性好，ｒ＝０９８９，Ｐ＜００１；对照组固相半排空时间（ＨＳＥＴ）为５８２±１７７分钟，液相半排空时间（ＨＬＥＴ）为２３５±９４分钟；病例组ＨＳＥＴ为９２５±２９６分钟，ＨＬＥＴ为３７２±１６６分钟；固相和液相两组差异均有显著性（ｔ＝３４７４和２４８５，Ｐ＜００１）。结论１３１ＩＢＳＡ鸡蛋餐、９９ｍＴｃＤＴＰＡ液体餐同时使用（双核素标准餐法）可为临床提供胃排空固体和液体食物的情况     

The effect of intermittent high-intensity running on gastric emptying of fluids in man

PURPOSE: This study examined the effect of variable-intensity shuttle running on gastric emptying of a carbohydrate-free placebo (Plac) drink and of a 6.4% carbohydrate-electrolyte (CHO) sports drink. METHOD: We compared the volume of test drink emptied during two 15-min periods of walking exercise (WE) with that during two 15-min periods of the Loughborough Intermittent Shuttle Test (LIST). Gastric emptying was measured on the four trials using a double-sampling aspiration technique in eight healthy males after ingestion of a 420 +/- 49 mL and a 168 +/- 20 mL bolus of the appropriate test drink at the start of the first and second exercise period, respectively. RESULTS: During the initial 15 min of exercise, the mean (+/-SD) volume of Plac (124 +/- 95 mL) and CHO (71 +/- 43 mL) drink emptied was similar between the two LIST trials, but the volume of Plac (227 +/- 85 mL) and CHO (159 +/- 63 mL) drinks emptied on the WE trials was greater than for the respective test drinks on the LIST trials. Similar volumes of test drinks were emptied on all trials (P = 0.20) during the second 15 min of exercise. Over the 30 min of each trial, the exercise intensity of the LIST reduced the volume of the Plac (211 +/- 108 mL) and CHO (208 +/- 83 mL) drink emptied compared with that on the WE trial for the Plac (396 +/- 74 mL) and CHO (293 +/- 73 mL) drink, respectively. CONCLUSIONS: The exercise intensity of the LIST is sufficient to slow gastric emptying of carbohydrate and noncarbohydrate containing drinks compared with walking. Dilute carbohydrate-electrolyte drinks empty at about the same rate as carbohydrate-free beverages during variable-intensity running.     

The effect of trimebutine maleate on gastric emptying in patients with non-ulcer dyspepsia

The study was designed to investigate the effect of trimebutine maleate, a drug used in both hyperkinetic and hypokinetic motility disorders, on gastric emptying in patients with non-ulcer dyspepsia having prolonged gastric emptying rates and to compare the parameters used for the determination of the lag period observed during the emptying of solid foods from the stomach. Gastric emptying was measured by the radionuclide technique. Twenty normal volunteers and 43 patients with non-ulcer dyspepsia participated in the study. Radionuclide imaging was performed by using a solid meal labeled with 99mTc-tin colloid. Of the patients with non-ulcer dyspepsia, 20 had prolonged gastric emptying. They were given three weeks of oral treatment with trimebutine maleate and had their radionuclide gastric emptying study repeated. Treatment with trimebutine maleate resulted in reduction in duration of the lag period and less retention of food at 100 minutes (p < 0.0005). After treatment with trimebutine maleate, no significant difference has been observed in the mean symptom score of patients with prolonged gastric emptying. Among the parameters used for the determination of the lag period, lag period determined by a mathematical equation (TLAG) has been found to be longer than the lag period determined by visual inspection of the images (VLAG) and there was correlation between the two parameters when the lag time was short.     

The effect of the Garren-Edwards Gastric Bubble on solid and liquid gastric emptying

To determine the effect of the Garren-Edwards Gastric Bubble (GEGB) on gastric emptying, radionuclide solid and liquid gastric emptying in 12 obese patients prior to insertion of the GEGB was studied. Four were restudied at one and seven days and ten patients were restudied at twelve weeks with the GEGB in place. There were no significant differences in liquid gastric emptying at one and seven days nor in solid and liquid gastric emptying at twelve weeks. Solid gastric emptying was significantly decreased from a mean of 63% to 31% after one day (P less than 0.05) and returned to preplacement baseline by seven days. These results indicate that gastric emptying is not significantly changed after twelve weeks with the GEGB in place. Therefore, the mechanism of action for weight reduction with the GEGB is not likely to be mediated by an effect on gastric emptying. However, the solid food-induced dyspeptic symptoms commonly noted 1-3 days after placement of the GEGB, which resolve within seven days, are probably explained by transiently delayed solid gastric emptying.     

Reproducibility of a solid and of a liquid caloric meal for gastric emptying studies

Simple meals are required for routine scintigraphic gastric emptying studies. We evaluated the reproducibility of a caloric liquid meal (520 kcal) compared to that of a solid meal (638 kcal) in 8 and 11 healthy volunteers, respectively. Gastric emptying rates and half-times were similar in two tests using the same meal, while the methods used to express lag times were not highly reproducible. The emptying rates and half-times of the liquid meal were delayed after the intake of bellafoline. In conclusion, this study demonstrates that: (a) gastric emptying rates and half-times are reproducible parameters for the expression of scintigraphic gastric emptying studies; (b) mathematical methods to express lag times are not highly reproducible; (c) a 500 kcal liquid meal is sensitive to the effects of bellafoline, a drug able to delay gastric emptying. Further clinical evaluation is required to test its applicability in routine studies.     

Serial gastric emptying studies: effect of preceding drinks

A widely used method for evaluating gastric emptying is the serial recovery method, in which several different test drinks are given and recovered in rapid succession. Recently, the validity of this method has been challenged (Brouns et al., Int. J. Sports Med. 8:175-189, 1987) by suggestions that the duodenal contents remaining from previous drinks may influence the gastric emptying of subsequent drinks. To evaluate whether this methodological issue might influence the results of gastric emptying studies, we studied six volunteer subjects. The gastric emptying rate of water was measured following a previous trial with either water or a concentrated maltodextrin solution (23% CHO). All trials were conducted at rest and consisted of a volume of 400 ml. The emptying rate of water was not different following either water or maltodextrin solution (14.9 vs 16.3 ml.min-1). We conclude that the serial recovery method remains a valid technique for measuring the rate of gastric emptying during rest and exercise.     

Effect of the Garren-Edwards gastric bubble on gastric emptying

The Garren-Edwards Gastric Bubble (GEGB) was introduced in 1984 as an alternative to surgery (jaw wiring, gastrointestinal bypass, vertical banded gastroplasty) for the treatment of morbid obesity in patients who had failed behavior modification therapy or dietary management for weight reduction. Its mechanism of action is unclear and previous reports have not demonstrated any significant consistent alteration in gastric emptying (GE) as measured by radionuclide techniques. Other proposed mechanisms include: placebo, hormonal, mechanical "satiety", behavioral modification, and neuronal. In order to determine the effect of the GEGB on GE, ten obese (mean % overweight = 89%) patients, 27-50 yr old (mean = 36 yr), had solid GE scans before and 5 wk after endoscopic placement of the bubble. GE scans were performed in six patients after removal (12 = wk residence time). The meal consisted of 300 microCi [99mTc]sulfur colloid in the form of a 300 kcal egg sandwich (egg white 248 g, white bread 40 g, butter 6 g; composition = CHO 40:PR 40: FAT 20) with 180 ml deionized water. Images were obtained in the anterior and posterior projections at 15-min intervals for 1 hr (four patients) or 2 hr (six patients) and the %GE (decay corrected geometric mean) was calculated. Unlike other studies involving the GEGB, adjunctive therapy in the form of dieting and behavior modification were not employed in this study. The effect of the GEGB alone in the treatment of obesity has not been previously evaluated. There was a significant (p less than 0.025) delay in gastric emptying at 1 hr (pre-bubble mean % gastric retention = 46%; bubble mean = 57%; n = 10). After removal, GE returned toward baseline (mean % gastric retention = 51%; n = 6) (p less than 0.05) (Student's t-test). The average weight loss was 5.5 lb (n = 10; p less than 0.025). One mechanism of action of the GEGB may be delayed gastric emptying resulting in early satiety and decreased food intake with resultant weight loss.     

The importance of volume in regulating gastric emptying

There is now substantive evidence that the provision of exogenous carbohydrate at high rates (1-2 g. min-1) can enhance performance during prolonged exercise. This finding has revived research into the factors determining the rate of exogenous carbohydrate delivery during exercise. While the rate of muscle oxidation of exogenous carbohydrate could be determined by the rate of gastric emptying or of intestinal carbohydrate absorption or of muscle glucose uptake and oxidation, most physiologists seem to have assumed that gastric emptying is the factor that limits the rate of exogenous carbohydrate delivery during exercise. Furthermore, studies of gastric emptying have suggested that the carbohydrate content of the ingested solution is an important factor determining its rate of gastric emptying. However, the findings of recent studies employing a repeated drinking design suggest that the gastric volume and therefore the pattern of drinking during exercise will have a significant, possibly major, influence on the rate of both carbohydrate and water delivery from any solution. This review considers this evidence and its practical implications for athletes who wish to ingest carbohydrate during exercise and for exercise physiologists designing studies to optimize carbohydrate delivery to muscle during exercise. It is proposed that, if gastric volume is an important determinant of the rate of gastric emptying, a more standardized method for reporting the rates of gastric emptying of different solutions should be adopted.     

The two-component stomach: effects of meal particle size on fundal and antral emptying

Using a dual-headed gamma camera and a standardized egg test meal labeled with 99mTc-sulfur colloid, the quantitative emptying of the total, proximal and distal stomach in five normal subjects was characterized. The same egg meal was given to the volunteers in 3 different forms: homogenized, and as 2.5 mm and 5.0 mm cubes on 3 separate occasions for a total of 15 studies. For the total stomach emptying, the lag phase and half emptying time (T1/2) obtained using a power exponential model were significantly shorter for the homogenized test meal than for the 2.5 mm and 5.0 mm cubed egg particles; the lag phases were 29 +/- 19 min (mean +/- SD) vs 55 +/- 26 (P less than 0.05) and 64 +/- 24 min (P less than 0.01), the T1/2's were 71 +/- 30 min vs 91 +/- 26 (P less than 0.05) and 104 +/- 30 min (P less than 0.05), respectively. For the proximal stomach, no statistically significant difference was observed among the 3 test meals; the T1/2s for the homogenized, 2.5 mm and 5.0 mm cubed meals were 65 +/- 26 min, 53 +/- 18 min and 64 +/- 20 min, respectively. For the distal stomach, both the peak activity (%) and time to peak activity (min) were significantly higher for the 2.5 mm cubes (43%, 54 min) and the 5.0 mm cubes (38%, 60 min) than for the homogenized eggs (16.4%, 30 min) (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

放射性核素胃排空显像

放射性胃排空显像具有方法简便、无创伤、可重复、符合生理状况、可精确定位等优点,它对消化道疾病病因学探讨和胃肠道功能研究具有重要的临床价值,是测定胃排空的金标准。本文结合临床工作经验和文献复习,对放射性核素胃排空测定方法、标记试餐标准化、胃感兴趣区的确定及常见影响因素等新技术、新观点加以评述。     

The two-component stomach: effects of meal particle size on fundal and antral emptying

Using a dual-headed gamma camera and a standardized egg test meal labeled with ^99mTc-sulfur colloid, the quantitative emptying of the total, proximal and distal stomach in five normal subjects was characterized. The same egg meal was given to the volunteers in 3 different forms: homogenized, and as 2.5 mm and 5.0 mm cubes on 3 separate occasions for a total of 15 studies. For the total stomach emptying, the lag phase and half emptying time (T _1/2) obtained using a power exponential model were significantly shorter for the homogenized test meal than for the 2.5 mm and 5.0 mm cubed egg particles; the lag phases were 29±19 min (mean±SD) vs 55±56 (P<0.05) and 64±24 min (P<0.01), the T _1/2s were 71±30 min vs 91±26 (P<0.05) and 104±30 min (P<0.05), respectively. For the proximal stomach, no statistically significant difference was observed among the 3 test meals; the T _1/2s for the homogenized, 2.5 mm and 5.0 mm cubed meals were 65±26 min, 53±18 min and 64±20 min, respectively. For the distal stomach, both the peak activity (%) and time to peak activity (min) were significantly higher for the 2.5 mm cubes (43%, 54 min) and the 5.0 mm cubes (38%, 60 min) than for the homogenized eggs (16.4%, 30 min) (P<0.01). The correlation between the lag phase for the total stomach and the time to peak activity in the distal stomach was excellent (r=0.85, P<0.001 suggesting that the lag phase may correspond to the maximum filling of the distal stomach. These results demonstrate quantitatively that the proximal portion of the stomach is mainly responsible for the receipt and storage of food and the emptying of liquids, while the distal stomach appears to be primarily involved with the processing of solid food before its passage through the pylorus.