儿童胃重复畸形的影像学表现

目的 分析儿童胃重复畸形的临床表现、影像特征及鉴别诊断要点,提高对该病的认识和影像学诊断水平。方法 回顾性分析5例经手术病理证实的儿童胃重复畸形的临床及影像学表现。采用CT及MRI观察病变的数量、位置、形态、密度或信号特点、与胃壁的关系、病变周围情况及强化特点等;上胃肠道造影动态观察胃肠道形态、走行、肠管蠕动、管腔充盈情况和对比剂通过情况,以及是否存在梗阻及充盈缺损等异常征象。结果 2例无症状者于平扫CT和MRI上表现为与邻近胃壁紧密连接的单发类圆形囊性肿物,囊壁较薄,边界清晰;3例有症状者平扫CT显示病变囊壁增厚,边界不清,所有病变囊壁均未见钙化。5例CT增强检查均显示囊壁强化而囊内无强化;上胃肠道造影显示,腔内型病变表现为胃窦部巨大充盈缺损并胃出口梗阻,腔外型病变对胃壁形成了外压性切迹。结论儿童胃重复畸形是临床少见的胃肠道先天性畸形,临床表现多变且特异性较差,影像学表现具有一定特征,术前全面的影像学检查有助于临床诊断和治疗。     

Simultaneous assessment of gastric accommodation and emptying: studies with liquid and solid meals.

The aim of this study was to develop a scintigraphic test to measure gastric emptying and accommodation simultaneously. METHODS: Gastric emptying and accommodation were measured in healthy subjects. To determine gastric accommodation, the stomach was imaged with SPECT 20 min after intravenous administration of 185 MBq (5 mCi) (99m)Tc-pertechnetate. After ingestion of 11 MBq (300 micro Ci) (111)In-diethylenetriaminepentaacertic acid in a liquid nutrient drink or an (111)In-oxine-labeled egg sandwich, dual-isotope imaging assessed SPECT gastric dimensions and gastric emptying every 20 min up to 240 min. Gastric accommodation was calculated as the percentage change in planar (2-dimensional) gastric cross-sectional area (CSA) using a left anterior oblique planar projection and the percentage change in total SPECT gastric voxel counts (3-dimensional) compared with the baseline image. RESULTS: With the liquid nutrient drink (9 subjects), maximal mean CSA (158% +/- 12% of baseline; P < 0.05) occurred 40 min after meal ingestion, when only 69% +/- 3% of the radiolabeled liquid nutrient drink remained in the stomach. At 120 min, mean CSA was 125% +/- 8% of baseline, but only 35% +/- 3% of the liquid nutrient drink remained in the stomach. Using SPECT to measure 3-dimensional volumes, maximal gastric volume occurred 20 min after meal ingestion (189% +/- 25% of baseline). With the solid egg meal (10 subjects), maximal total CSA (159% +/- 13% of baseline) occurred immediately after meal ingestion; total CSA remained significantly increased above baseline for the first 3 h after ingestion of the egg meal, despite only 12% +/- 4% gastric retention at 3 h. Using SPECT to measure 3-dimensional volumes, maximal gastric volume occurred immediately after the meal (184% +/- 19% of baseline). CONCLUSION: This method permits simultaneous measurement of gastric emptying and accommodation. In healthy subjects, the gastric accommodation response is prolonged and persists despite nearly complete emptying of a liquid or solid meal.     

Dual-radionuclide simultaneous gastric emptying and bile transit study after gastric surgery with double-tract reconstruction

OBJECTIVE: The physiology of gastrointestinal transfer function after proximal gastrectomy with bypass-tract reconstruction is not well understood. We applied a simultaneous dual-radionuclide method with a hepatobiliary imaging and gastric emptying study to evaluate physiologic alterations occurring after surgery. METHODS: Nineteen patients with early gastric cancer, including 9 preoperative control patients and 10 who had proximal gastrectomy and double-tract reconstruction surgery were examined by dual-radionuclide hepatobiliary and gastric emptying studies (99mTc PMT and 111In DTPA). Retention fraction in the stomach at 3 minutes (R3) and 60 minutes (R60) and gastric emptying half-time (GET) were calculated. Bile reflux and mixture of bile and food were also evaluated. RESULTS: The retention fractions of R3 and R60 were significantly lower in the double-tract reconstruction group than those in the preoperative group. GET differed significantly between the double-tract and preoperative groups (20.7 min +/- 7.1 min and 36.2 min +/- 11.0 min, p = 0.0018). The mixture of bile and food was not good in the double-tract reconstruction group (p = 0.014 vs. preoperative). Patients with a large residual stomach showed slower initial emptying (p = 0.0068) and a better mixture of bile and food (p = 0.058) compared to those with a small residual stomach. The bile reflux was not significantly increased after surgery. CONCLUSION: The dual-radionuclide gastrointestinal and hepatobiliary imaging was feasible and could demonstrate characteristic transit patterns of the foods and bile in the double-tract reconstruction procedure. A larger residual stomach, if possible, is desirable to provide better transfer and mixing of bile and foods.     

Gastrointestinal transit times in mice and humans measured with 27Al and 19F nuclear magnetic resonance.

Gastric emptying and gastrointestinal (GI) transit times in mice and humans were monitored noninvasively by using 27Al and 19F nuclear magnetic resonance (NMR). Al(3+) bound to ion-exchange resin and perfluorononane were administered orally as selective and specific markers for the stomach and the entire GI tract, respectively. 27Al- and 19F-MR spectroscopy (MRS) was employed to follow quantitatively boli of the mixed markers in awake, fed mice over a period of 48 hr. The selectivity of the markers was confirmed by whole-body 1H-, 27Al-, and 19F-MRI of anesthetized mice. Gastric emptying in humans was also monitored with 27Al-MRS of aluminum-loaded ion exchange resin. GI transit was assessed by 19F projection imaging of pharmaceutical capsules tagged with perfluorononane. Quantitative analysis of the MR data revealed that gastric emptying in humans proceeded linearly, whereas in mice an exponential decay was observed. This difference is explained by the respective feeding patterns of humans and mice. Humans usually achieve nearly complete gastric emptying before each meal. In contrast, very short delays between successive food intakes in small animals result in successive dilution of the stomach contents. For stomach emptying in mice the exponential decay constant was 74 min, whereas the half-time of the linear gastric emptying in humans was 30 min.     

Effect of proximal vagotomy and Roux-en-Y diversion on gastric emptying kinetics in asymptomatic patients

The role of the distal stomach in gastric emptying was studied. Ten patients with proximal gastric vagotomy (PV) and 10 age-matched patients with Roux-en-Y gastro-jejunostomy (R-Y) were compared with 10 healthy controls. Gastric emptying of solids and liquids was determined by the use of Tc-99m SC scrambled eggs and In-111 DTPA. In PV, gastric emptying of both solids and liquids was delayed; the prolongation with solids was mainly accounted for by an abnormal lag phase. In R-Y patients, no lag phase was observed, and the solid emptying curve pattern was characterized by early rapid emptying followed by very slow emptying. Both the solid and liquid phases were prolonged. The lag phase is affected by proximal vagotomy and is mainly determined by the distal stomach, which appears to be essential for normal emptying.     

Usefulness of measuring the gastric emptying time in a case of brittle diabetes

Gastric emptying time measurement by radionuclide study, although quite informative, is rarely remembered in clinical practice. We presented a patient with brittle diabetes who had multiple emergency admissions due to hypoglycemia under routinely prescribed insulin therapy. She had severe gastroparesis, which was determined by scintigraphic gastric emptying study (gastric half-emptying time = 260 min for a mixed meal). She had not presented to the emergency service for two years because of only a slight change the timing of her insulin administration time (after meal instead of before meal) in the light of gastric-emptying study.     

Gastric motor function and emptying in the right decubitus and seated body position as assessed by magnetic resonance imaging

PURPOSE: To determine the effect of the right decubitus lying body position (RP) on relevant parameters of human gastric motor function in healthy volunteers. MATERIALS AND METHODS: Postprandial gastric function after ingestion of a solid/liquid meal (150 g/150 mL) was assessed over 90 minutes in volunteers in the RP and seated position (SP). Ten healthy volunteers were imaged using two MRI systems that differed in architecture and field strength. Stomach and intragastric air volume, intragastric meal distribution, gastric emptying, and gastric peristalsis were compared between the RP and SP. RESULTS: Body position did not affect gastric relaxation (RP, 372 mL vs. SP, 384 mL) and initial gastric volumes (stomach: RP, 458 mL vs. SP, 462 mL; meal: RP, 377 mL vs. SP, 399 mL; intragastric air: RP, 110 mL vs. SP, 98 mL). Postprandial stomach volume and gastric activity (RP and SP, 3.1 minute(-1)) were also similar. Meal emptying showed different characteristics, resulting in a significant but small difference in meal volume of -43 mL at t = 90 minutes (P < 0.05). CONCLUSION: Gastric MRI in RP is feasible for clinical research assessing gastric motor function. The subtle difference in meal emptying may be induced by posture-dependent vagal activity. This study confirms that MRI is a highly sensitive imaging technique for assessing gastrointestinal function in humans.     

Monitoring of gallbladder and gastric coordination by EPI

PURPOSE: To assess for the first time the potential of echo-planar magnetic resonance imaging (EPI) for measuring simultaneously both gallbladder and gastric emptying. MATERIALS AND METHODS: Eight healthy subjects ingested 500 mL of an acid-stable liquid test meal containing 15% olive oil and flavoring. Every 20 minutes for three hours thereafter, a rapid EPI multislice set was acquired across the whole abdomen, using a dedicated whole-body 0.5-T EPI scanner. RESULTS: The bile in the gallbladder and the test meal in the stomach appeared bright in the EPI images, aiding localization and region of interest analysis. We measured the gallbladder emptying curve and fitted the data to a simple analytical model. The mean fasted gallbladder volume was 25 +/- 4 mL, comparable to previously published MRI and ultrasound values. Gastric emptying data fitted well to a linear model linear (R2 = 0.99), and we observed an exponential (R2 = 0.98) relationship between gallbladder and gastric volumes for the first 90 minutes. CONCLUSION: This study shows the potential of EPI to monitor simultaneously and noninvasively the emptying of the gallbladder and of the gastric lumen. No contrast enhancing agents are needed. This method could overcome the limitations of previous gamma scintigraphy and ultrasound techniques.     

Effect of early emptying on quantitation and interpretation of liquid gastric emptying studies of infants and young children.

This study assesses the effect of emptying that occurs during feeding on quantitation and interpretation of liquid gastric emptying studies of infants and young children. METHODS: Forty-nine 99mTc-sulfur colloid liquid gastric emptying studies of 44 children (22 boys, 22 girls; mean age, 20 mo; age range, 2-46 mo) fed orally or by gastrostomy tubes were evaluated. Gastric residuals quantitated by 2 commonly used methods, the first of which does not account for early emptying and the second of which does, were compared. With the first method, residual relative to activity in the stomach at the start of imaging (Rg) was quantified by comparing activity in a region of interest (ROI) drawn about the stomach on the final image to activity in an ROI drawn about only the stomach at the start of imaging. With the second method, residual relative to total dose (Rt) was quantified by comparing activity in the same final ROI to activity in an ROI that included stomach and small bowel at the start of imaging. Studies were interpreted independently for Rg and Rt considering a value >70% as evidence of delayed emptying. RESULTS: Rt was lower than Rg by 15%-16% for the entire population, for patients fed orally, and for patients fed by gastrostomy tube. These differences reached statistical significance (P < 0.0001). In 31 of 49 studies, R1 was lower than Rg by > or =10%. In 8 studies, emptying classified as delayed on the basis of Rg was classified as nondelayed on the basis of Rt. Clinical decisions based on Rt did not require later management changes that would have indicated that treatment of gastric dysmotility had been postponed in any patient. CONCLUSION: Emptying that occurs during feeding should be factored into quantitation of liquid gastric emptying in infants and young children. Not recognizing and accounting for early emptying results in overestimated gastric residuals and can lead to classification of emptying as delayed in children whose residuals of the total administered dose are within a recognized range of normal.     

Validation of corrections for errors in collimation during measurement of gastric emptying of nuclide-labeled meals

The study was undertaken to validate phantom-derived corrections for errors in collimation due to septal penetration or scatter, which vary with the size of the gastric region of interest (ROI). Six volunteers received 495 ml of 20% glucose labeled with both In-113m DTPA and Tc-99m DTPA. Gastric emptying of each nuclide was monitored by gamma camera as well as by periodic removal and reinstillation of the meal through a gastric tube. Serial aspirates from the gastric tube confirmed parallel emptying of In-113m and Tc-99m, but analyses of gamma-camera data yielded parallel emptying only when adequate corrections were made for errors in collimation. Analyses of ratios of gastric counts from anterior to posterior, as well as analyses of peak-to-scatter ratios, revealed only small, insignificant anteroposterior movement of the tracers within the stomach during emptying. Accordingly, there was no significant improvement in the camera data when corrections were made for attenuation with intragastric depth.     

The effects of consuming carbohydrate-electrolyte beverages on gastric emptying and fluid absorption during and following exercise

A variety of beverages formulated to provide fluid, carbohydrates, and electrolytes during and following exercise are commercially available. Such 'sport drinks' commonly contain 4 to 8% carbohydrate (as glucose, fructose, sucrose or maltodextrins) and small amounts of electrolytes (most often sodium, potassium, and chloride). The efficacy of consuming such beverages has been questioned primarily because of concern that beverage carbohydrate content may inhibit gastric emptying rate and fluid absorption during exercise, thereby jeopardizing physiological homeostasis and impairing exercise performance. Gastric motor activity, and consequently gastric emptying rate, is governed by neural and humoral feedback provided by receptors found in the gastric musculature and proximal small intestine. Gastric emptying rate may be influenced by a variety of factors including, but not limited to, the caloric content, volume, osmolality, temperature, and pH of the ingested fluid, diurnal and interindividual variation, metabolic state (rest/exercise), and the ambient temperature. The caloric content of the ingested fluid appears to be the most important variable governing gastric emptying rate, providing a mean caloric efflux from the stomach of 2.0 to 2.5 kcal/min for ingested fluid volumes less than 400 ml. At rest, gastric emptying is inhibited by solutions containing calories in a manner independent of the nutrient source (i.e. carbohydrate, fat or protein). Consequently, plain water is known to empty from the stomachs of resting subjects at rates faster than solutions containing calories. Gastric emptying is increasingly inhibited as the caloric content of the ingested fluid increases. During moderate exercise (less than 75% VO2max), gastric emptying occurs at a rate similar to that during rest; more intense exercise appears to inhibit gastric emptying. When fluids are consumed at regular intervals throughout prolonged exercise (greater than 2 hours), postexercise aspiration of stomach contents reveals that solutions containing up to 10% carbohydrate empty at rates similar to plain water. There is ample physiological justification for the addition of glucose, fructose, sodium, potassium and chloride to fluid replacement beverages. Fluid absorption in the small intestine is stimulated by glucose and sodium (and to a lesser extent by fructose and other electrolytes). Glucose and sodium are absorbed via a common membrane carrier in the mucosal epithelium of the proximal small intestine. The potentiation of sodium uptake by glucose establishes an osmotic gradient for fluid absorption.(ABSTRACT TRUNCATED AT 400 WORDS)     

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.     

Relationships between oesophageal transit and solid and liquid gastric emptying in diabetes mellitus

In 87 randomly selected diabetic patients (67 type 1, 20 type 2) and 25 control subjects, gastric emptying of digestible solid and liquid meals and oesophageal transit of a solid bolus were measured with scintigraphic techniques. Gastrointestinal symptoms, autonomic nerve function and glycaemic control were evaluated in the diabetic patients. Gastric emptying and oesophageal transit were slower (P less than 0.001) in the diabetic patients compared with the control subjects, and each was delayed in about 40% of them. There was a relatively weak (r = 0.32; P less than 0.01) relationship between solid and liquid gastric emptying, and no significant correlation (r = 0.11, NS) between oesophageal transit and gastric emptying of the solid meal. Scores for upper gastrointestinal symptoms and autonomic nerve function correlated weakly (r = 0.21; P less than 0.05) with both oesophageal transit and gastric emptying. Gastric emptying of the liquid meal was slower (P less than 0.05) in patients with blood glucose concentrations greater than 15 mmol/l. These results indicate that gastric emptying in patients with diabetes mellitus should be assessed by liquid as well as by solid test meals and that oesophageal transit should not be used as a predictor of generalised diabetic gastroenteropathy.     

用显示子检查不同胃型胃排空时间的对照研究

目的：不同胃型胃排空的对比研究，方法：1200例不同胃型健康志愿者，口服实验餐并连续观察显示子由胃排出的数目。结果：经统计学分析，瀑布型胃的胃排空与其它胃型有明显差异（P＜0．05）。结论：瀑布型胃属于一种潜病理（亚健康）状态。     

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.     

营养不良患儿胃运动及排空检测

目的 研究营养不良患儿的胃动力及排空.方法应用B型实时超声对30例营养不良患儿液体试验餐后的胃运动与排空功能进行检测.结果 与正常组比较,营养不良患儿餐后胃体蠕动和胃窦收缩频率明显减少,液体胃排空速度明显减慢（P〈0.01）.结论 提示对营养不良症的治疗可应用促进胃动力药物（如吗丁林,普瑞博恩）或采取其他相应措施,以增加胃排空速度,增加能量的摄入,提高治疗效果.     

睡眠剥夺对大鼠胃酸分泌和胃运动影响的实验研究

目的：观察急性睡眠剥夺对大鼠胃酸分泌以及胃排空和胃电活动的影响。为防治因睡眠剥夺引起的胃功能紊乱提供理论依据。方法：本研究在成功制作了睡眠剥夺大鼠模型的基础上，采用化学分析测定胃酸浓度，应用放射分析法和液相胃排空的方法检测胃的排空，利用浆膜法检测胃电的变化情况。结果：随着睡眠剥夺发生时间的不断延长，大鼠胃酸分泌逐渐增加，睡眠剥夺3d，其胃酸的水平与睡眠剥夺1d相比，有显著性差异（P〈0．05）；睡眠剥夺5d的胃酸水平增加更为明显，与睡眠剥夺的3d相比有显著性差异（P〈0．01）；而在睡眠剥夺7d时，胃酸的水平不再明显增加，与睡眠剥夺5d相比没有显著性差异（P〉0．05）。急性睡眠剥夺导致胃排空速率改变，随着睡眠剥夺时间的延长，胃的排空速率逐渐降低；胃电活动在餐前逐渐降低，而餐后无明显规律，呈现紊乱状态。结论：急性睡眠剥夺可以导致胃酸分泌的增加以及胃运动功能的紊乱，而且紊乱程度与时间关系密切。     

Gastric emptying in patients with chronic liver diseases

There have been a number of reports of gastric emptying in cirrhosis, all with unconfirmed results. Moreover, the mechanism for delayed emptying in cirrhotic patients is unclear. We evaluated gastric emptying in patients with chronic hepatitis and cirrhosis by means of gastric emptying scintigraphy. METHODS: The subjects were 18 normal controls and 75 patients with chronic viral hepatitis (50 patients had chronic hepatitis and 25 patients had cirrhosis). Tc-99m diethyltriamine pentaacetic acid labeled solid meals were used to evaluate gastric emptying; the half-time (T 1/2) of which was calculated. Digestive symptom scores were determined at the time of gastric emptying tests. RESULTS: Fourteen (28%) of 50 patients with chronic hepatitis and 16 (64%) of 25 patients with cirrhosis had delayed gastric emptying. T 1/2 in patients with cirrhosis was significantly higher than that in normal controls and patients with chronic hepatitis (p = 0.0001 and 0.0003, respectively). The difference between T 1/2 in patients with chronic hepatitis and that in normal controls was not significant. On regression analysis, two indices-the serum albumin level and platelet count-were found to be significantly related to delayed gastric emptying. CONCLUSIONS: Gastric emptying was more delayed in cirrhotic patients than in those with chronic hepatitis and normal controls. Delayed gastric emptying may be related to liver function and portal hypertension.     

Gallbladder contraction, gastric emptying and antral motility: single visit assessment of upper GI function in untreated celiac disease using echo-planar MRI

PURPOSE: To assess gallbladder contraction, gastric emptying, and antral motility in untreated celiac patients and healthy controls using a single MRI examination. MATERIALS AND METHODS: Gallbladder emptying, gastric emptying, and antral motility were measured in 15 celiac patients and 15 age/sex-matched healthy controls following a 323-kcal test meal using EPI techniques. Postprandial dyspepsia scores were recorded on a questionnaire. RESULTS: Fasting gallbladder volume (P=0.01) and the volume of bile ejected postprandially (P=0.014) were increased in celiacs. Gastric emptying tended to be slower in celiacs (P=0.142). Three celiac patients with severe postprandial dyspepsia and total villous atrophy had pathologically delayed gastric emptying and increased fasting gallbladder volume. Antral contractions were absent in five out of 14 patients (36%) five minutes after the meal, but in none of 10 volunteers in whom the antrum could be visualized (P=0.128). CONCLUSION: This study shows that using MRI, multiple parameters related to upper gastrointestinal function in celiac disease can be measured in a single noninvasive study, whereas previously three separate visits would have been required. Celiacs have increased fasting gallbladder volumes and tend to have slower gastric emptying.     

Nuclear medicine evaluation of motion sickness and medications on gastric emptying time

Diminished gastric motility and lack of bowel sounds have been observed in astronauts aboard the Space Shuttle (4). In this study subjects were given scopolamine 0.6 mg with d-amphetamine 5 mg with and without neostigmine 15 mg. Neostigmine 15 mg alone was also compared with placebo for effect on gastric emptying time. In an additional test, subjects performed head movements in a rotating chair to an end-point of motion sickness short of vomiting. Ten ounces of isotonic saline containing 1 mCl of Tc 99mDPTA was ingested 2 h after the medications and immediately after rotation. The counts from stomach contents were monitored with a Picker small field of view gamma camera every 30 s for 1 h. Gastric motility was inhibited by scopolamine and amphetamine with 14% residual count at the end of 1 h. When neostigmine was added to this combination the results were in the placebo range. Motion sickness produced a profound inhibition of gastric emptying with a 47% residual count. The results indicate that the gastric stasis encountered in space is due mainly to motion sickness with a minimal contribution from the antimotion sickness drugs.