Gastroesophageal reflux--the acid test: scintigraphy or the pH probe?

Reflux scintigraphy in gastro-esophageal reflux disease: a comparison study with 24 hour pH-impedance monitoring

OBJECTIVE

Reflux scintigraphy is often used to diagnose gastro-esophageal reflux disease (GERD). However, the efficacy of this study remains controversial. Our aim was to determine the role of reflux scintigraphy in diagnosing GERD by comparing it to 24 h combined pH-impedance study as the gold standard.

MATERIALS AND METHODS

Adult patients who presented for investigations of reflux symptoms were prospectively recruited into the study. All patients underwent high resolution esophageal manometry and those with major motor disorders of the esophagus were excluded. Eligible patients immediately underwent reflux scintigraphy following insertion of the pH-impedance catheter.

RESULTS

Thirty patients were included in the study. Using a total acid exposure time (AET) of >4.2% as the reference for abnormal acid reflux, reflux scintigraphy had a sensitivity and specificity of 62.5 and 68.2%, respectively, in detecting acid reflux. When compared to AET >6%, reflux scintigraphy had a sensitivity and specificity of 66.7 and 62.5%, respectively, and a positive predictive value of 30.8% and a negative predictive value of 88.2%. There were no associations between outcomes of reflux scintigraphy and total AET (p = .46), total (acid or non-acid) reflux events (p = 0.11), proximal AET (p = .33) or the number of proximal reflux episodes (p = .75) on 24 h pH-impedance study.

CONCLUSIONS

Reflux scintigraphy has limited role in diagnosing GERD when compared to 24 h combined pH-impedance monitoring.

A narrative review of gastroesophageal reflux in the pediatric patient

Gastroesophageal reflux (GER) is the retrograde passage of gastric contents into the esophagus. It is a physiologic condition that is common in neonates, typically resolves spontaneously, and does not result in clinically significant complications. When pathologic, gastroesophageal reflux disease (GERD) can cause numerous complications including persistent emesis, failure to thrive, aspiration, and respiratory symptoms. While a diagnosis can often be made from a thorough history and physical, some patients may require further testing. In general, many clinicians will reserve extensive investigation such as multiple intraluminal impedance and pH monitoring for patients with a confounding clinical picture or relative contraindications to medical or surgical management. Whereas most pediatric GER resolves spontaneously, medical management including lifestyle changes, changes to feeds, and the use of H₂-antagonists and/or proton pump inhibitors (PPIs) can be utilized to alleviate symptoms. Surgical treatment is reserved for patients who are refractory to medical management or have suffered significant complications as a consequence of GER. In this article we seek to provide a concise but detailed review of recent updates in the understanding, work up and management of GER in the pediatric patient. A summary of new technologies used in the diagnostic and therapeutic arms of this disease are included.

ACR Appropriateness Criteria® Vomiting in Infants

Vomiting in infants under the age of 3 months is one of the most common reasons for parents to seek care from their doctor or present to an emergency room. The imaging workup that ensues is dependent on several factors: age at onset, days versus weeks after birth, quality of emesis, bilious or nonbilious vomiting, and the initial findings on plain radiograph, suspected proximal versus distal bowel obstruction. The purpose of these guidelines is to inform the clinician, based on current evidence, what is the next highest yield and most appropriate imaging study to pursue a diagnosis. The goal is rapid and accurate arrival at a plan for treatment, whether surgical or nonsurgical. The following modalities are discussed for each variant of the symptom: plain radiography, fluoroscopic upper gastrointestinal series, fluoroscopic contrast enema, ultrasound of the abdomen, nuclear medicine gastroesophageal reflux scan. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Role of esophageal manometry in children with refractory gastroesophageal reflux symptoms

BACKGROUND

We investigated the prevalence of psychiatric referral, frequency of repeat upper gastrointestinal (UGI) contrast studies, and esophagogastroduodenoscopy (EGD) in children with ineffective esophageal motility (IEM) before the confirmation of esophageal dysmotility.

METHODS

A total of 19 children (nine boys, 10 girls; mean age, 13.80 ± 5.10 years) with symptoms of refractory gastroesophageal reflux (GER) who underwent high-resolution esophageal impedance manometry (HRIM) were enrolled in this retrospective analysis. Refractory GER symptoms were defined as persistent symptoms even under acid-suppression therapy for 8 weeks in this study. Clinical data including age, gender, time from symptom onset to diagnosis, and number of UGI contrast studies and EGD before diagnosis were obtained. HRM parameters and the prevalence of psychiatric referral were also analyzed.

RESULTS

There are 14 children (73.68%) diagnosed with IEM by HRIM, and another 5 children (26.32%) diagnosed as GER disease (GERD) by EGD. A significant proportion of IEM children were misdiagnosed with psychological problems compared with the GERD children (78.57% vs 20.00%, P = 0.04). Three IEM children (21.43%) received antipsychotic and antidepressant agents before diagnosis of IEM, and all of them discontinued these medications after diagnosis. IEM children underwent a greater number of UGI contrast studies (1.07 ± 0.92 vs 0.20 ± 0.45; P = 0.02) and EGD (2.36 ± 2.50 vs 0.60 ± 0.55; P = 0.03) before HRM than GERD children.

CONCLUSIONS

Esophageal manometry for the diagnosis of IEM should be considered in children with GER symptoms refractory to acid-suppression therapy for 8 weeks to avoid repeat UGI contrast studies, EGD, and psychological therapy.

Scintigraphic Evaluation of Gastroesophageal Reflux and Pulmonary Aspiration in Children

Gastroesophageal reflux (GER) and pulmonary aspiration are encountered in children of all ages. Signs, symptoms, and complications vary from mild and transient to severe life-threatening conditions. This review will present relevant clinical information on these conditions as well as common diagnostic procedures. The role of scintigraphic techniques used in the evaluation of these conditions will be discussed in detail including protocols and performance in comparison to other diagnostic methods.

Comparison of multichannel intraluminal impedance-pH monitoring and reflux scintigraphy in pediatric patients with suspected gastroesophageal reflux

AIM

To evaluate the agreement of multichannel intraluminal impedance-pH monitoring (MII-pHM) and gastroesophageal reflux scintigraphy (GES) for the diagnosis of gastroesophageal reflux disease.

METHODS

Seventy-five consecutive patients with suspected gastroesophageal reflux disease (GERD) underwent 24-h combined MII-pHM recording and one hour radionuclide scintigraphy during the course of the MII-pHM study. Catheters with 6 impedance channels and 1 pH sensor were placed transnasally. Impedance and pH data analysis were performed automatically and manually. For impedance monitoring, reflux was defined as a retrograde 50% drop in impedance, starting distally and propagating retrogradely to at least the next two more proximal measuring channels. Reflux index (RI, percentage of the entire record that esophageal pH is < 4.0) greater than 4.2% for pHM and number of refluxes more than 50 for 24 h for MII were accepted as positive test results. At scintigraphy, 240 frames of 15 seconds duration were acquired in the supine position. Gastroesophageal reflux was defined as at least one reflux episode in the esophagus. After scintigraphic evaluation, impedance-pH recordings and scintigraphic images were evaluated together and agreement between tests were evaluated with Cohen’s kappa.

RESULTS

Sufficient data was obtained from 60 (80%) patients (34 male, 56.7%) with a mean age of 8.7 ± 3.7 years (range: 2.5-17.3 years; median: 8.5 years). Chronic cough, nausea, regurgitation and vomiting were the most frequent symptoms. The mean time for recording of MII-pHM was 22.8 ± 2.4 h (range: 16-30 h; median: 22.7 h). At least one test was positive in 57 (95%) patients. According to diagnostic criteria, GERD was diagnosed in 34 (57.7%), 44 (73.3%), 47 (78.3%) and 51 (85%) patients by means of pHM, MII, GES and MII-pHM, respectively. The observed percentage agreements/κ values for GES and pHM, GES and MII, GES and MII-pHM, and MII and pHM are 48.3%/-0.118; 61.7%/-0.042; 73.3%/0.116 and 60%/0.147, respectively. There was no or slight agreement between GES and pHM alone, MII alone or MII-pHM. pH monitoring alone missed 17 patients compared to combined MII-pHM. The addition of MII to pH monitoring increased the diagnosis rate by 50%.

CONCLUSION

No or slight agreement was found among pH monitoring, MII monitoring, MII-pH monitoring and GES for the diagnosis of gastroesophageal reflux disease.

Scintigraphic scoring system for grading severity of gastro-esophageal reflux on 99mTc sulfur colloid gastro-esophageal reflux scintigraphy: A prospective study of 39 cases with pre and post treatment assessment

Aim:

The study aimed at developing a scoring system for scintigraphic grading of gastro-esophageal reflux (GER), on gastro-esophageal reflux scintigraphy (GERS) and comparison of clinical and scintigraphic scores, pre- and post-treatment.

Materials and Methods:

A total of 39 cases with clinically symptomatic GER underwent 99mTc sulfur colloid GERS; scores were assigned based on the clinical and scintigraphic parameters. Post domperidone GERS was performed after completion of treatment. Follow up GERS was performed and clinical and scintigraphic parameters were compared with baseline parameters.

Results:

Paired t-test on pre and post domperidone treatment clinical scores showed that the decline in post-treatment scores was highly significant, with P value < 0.001. The scintigraphic scoring system had a sensitivity of 93.9% in assessing treatment response to domperidone, specificity of 83.3% i.e., 83.3% of children with no decline in scintigraphic scores show no clinical response to Domperidone. The scintigraphic scoring system had a positive predictive value of 96.9% and a negative predictive value of 71.4%.

Conclusion:

GERS with its quantitative parameters is a good investigation for assessing the severity of reflux and also for following children post-treatment.

Diagnosis of gastroesophageal reflux and anti-reflux procedures among Polish children with gastrostomies: a 10-year nationwide analysis

BACKGROUND/OBJECTIVES

To analyse the approach to diagnose gastroesophageal reflux (GER) and the qualification criteria for anti-reflux (AR) procedures in Polish children fed via gastrostomy between 2000 and 2010.

SUBJECTS/METHODS

An electronic questionnaire containing questions on the demographic and clinical data of patients with gastrostomies was distributed to six Polish centres of nutritional therapy. The portion pertaining to GER included data on clinical exponents, diagnostic procedures (pH-metry, pH-impedance, scintigraphy and upper gastrointestinal (GI) series) and AR.

RESULTS

In total, 348 children (M199/F149; age at gastrostomy 5.78±5.49 years) were included. Data on the diagnosis of GER and the AR criteria were available for 343 and 336 subjects, respectively. Percutaneous endoscopic gastrostomy was performed in 258/348 patients (74.1%), while surgery was performed in 80/348 patients (23%). The data from 10/348 (2.9%) cases were unavailable. At least one of the tests for GER was conducted in 177/343 (51.6%) of patients: pH-metry in 74/343 (21.6%), pH-impedance in 17/343 (5.0%), scintigraphy in 60/343 (17.5%) and upper GI series in 102/343 (29.7%). GER was reported in 114/343 cases (33.2%), and fundoplication was performed in 87 children (76.3% of patients with GER). The highest congruence between a positive test result and the decision to perform fundoplication was documented in cases of scintigraphy and upper GI series (P=0.00000 and P=0.00191, respectively). A significant increase in the prevalence of simultaneous gastrostomy and AR was observed over the decade analysed (r=0.8, P=0.009). This study revealed a centre-specific attitude towards the diagnosis of GER and the assessment of qualifications for fundoplication in Polish gastrostomy-fed children.

CONCLUSIONS

The unified diagnostic algorithm of GER and the universal qualification criteria for AR procedures need to be defined for gastrostomy-fed children.

Role of laryngoscopy in children with respiratory complaints and suspected reflux

BACKGROUND

In recent years, laryngopharyngeal reflux (LPR) in children has been taken into consideration.

OBJECTIVE

The aim of this study was to assess the laryngoscopic findings in children diagnosed LPR and/or gastro-oesophageal reflux (GERD).

METHODS

The findings of 49 patients with at least one or more respiratory complaint such as chronic cough, wheezing, hoarseness, recurrent laryngitis, and throat clearing/postnasal discharge suggesting LPR were evaluated retrospectively. The diagnosis of LPR+GERD or GERD was done by the clinical history and 24 h double-probe pH monitoring and/or scintigraphy.

RESULTS

Thirty eight out of 49 patients examined by laryngoscopy underwent 24 h double-probe pH monitoring and/or scintigraphy. Thirty of them were diagnosed as LPR+GERD or GERD by any test positivity. Twelve of 30 patients diagnosed with LPR+GERD or GERD had a positive laryngeal finding on the examination of fibre optic laryngoscopy. The most common finding with eight cases was arytenoid erythema A sensitivity of 40% and specificity of 50% for the laryngoscopy in the diagnosis of LPR/GERD were found.

CONCLUSION

In children with unexplained respiratory symptoms, laryngopharyngeal reflux should be suspected. Therefore, until enough data on this issue in the literature accumulates, the history and the laboratory findings of the patients obtained from various techniques to document paediatric LPR should be evaluated together.

Pediatric gastroesophageal reflux clinical practice guidelines: joint recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN)

OBJECTIVE

To develop a North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) international consensus on the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

METHODS

An international panel of 9 pediatric gastroenterologists and 2 epidemiologists were selected by both societies, which developed these guidelines based on the Delphi principle. Statements were based on systematic literature searches using the best-available evidence from PubMed, Cumulative Index to Nursing and Allied Health Literature, and bibliographies. The committee convened in face-to-face meetings 3 times. Consensus was achieved for all recommendations through nominal group technique, a structured, quantitative method. Articles were evaluated using the Oxford Centre for Evidence-based Medicine Levels of Evidence. Using the Oxford Grades of Recommendation, the quality of evidence of each of the recommendations made by the committee was determined and is summarized in appendices.

RESULTS

More than 600 articles were reviewed for this work. The document provides evidence-based guidelines for the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

CONCLUSIONS

This document is intended to be used in daily practice for the development of future clinical practice guidelines and as a basis for clinical trials.

GERD or not GERD: the fussy infant

A global evidence-based consensus has defined gastroesophageal reflux disease (GERD) as 'a condition, which develops when the reflux of stomach contents causes troublesome symptoms and/or complications.' The manifestations of GERD can be divided into esophageal and extraesophageal syndromes, and include vomiting, poor weight gain, dysphagia, abdominal or substernal/retrosternal pain, esophagitis and respiratory disorders. The extraesophageal syndromes have been divided into established and proposed associations: established would include cough, laryngitis, asthma and dental erosion ascribable to reflux, whereas proposed associations would include pharyngitis, sinusitis, idiopathic pulmonary fibrosis and recurrent otitis media. Uninvestigated patients with esophageal symptoms without evidence of esophageal injury would be considered to have asymptomatic esophageal syndromes, whereas those with demonstrable injury are considered to have esophageal syndromes with esophageal injury. Therefore, this allows symptoms to define the disease but permits further characterization if mucosal injury is found. Within the syndromes with associated injury are reflux esophagitis, stricture, Barrett's esophagitis and adenocarcinoma. This review will address definitions of GER and GERD-associated symptoms and treatment options.

Imaging of the Esophagus in Children

The main role of the esophagus is to facilitate passage of food from the mouth to the stomach. A number of conditions can alter esophageal structure or function including congenital anomalies, trauma, infection, and neoplasm. This article reviews the anatomy, imaging evaluation, and common problems seen in the pediatric thoracic esophagus.

Reliability of radionuclide gastroesophageal reflux studies using visual and time-activity curve analysis: inter-observer and intra-observer variation and description of minimum detectable reflux

Radionuclide studies have gained wide acceptance in the evaluation of infants and children with gastroesophageal reflux (GER). For correct interpretation of scan results, knowledge of inter-observer and intra-observer variability and minimum detectable reflux volume is essential. In this study, we evaluated the methodological issues underlying the visual assessment of GER and time activity curve analysis. An in vitro model of stomach and oesophagus was established to determine the minimum detectable reflux by placing various volumes and concentrations representing the diluted activity in the stomach. In the clinical part 99 patients were imaged for 1 h after oral administration of 99mTc sulfur colloid. Eleven patients were excluded from the study either due to incomplete clinical data or suboptimal image quality. Frames of 16 s each, and time-activity curves which were generated after drawing regions of interest from the oesophagus, were read three times by an experienced nuclear medicine physician and a resident in training. On the phantom study, the concentration, volume and duration were the determining factor for the visualization of reflux. In the clinical part, the overall incidence of GER in 88 patients was 69%. The mean intra- and inter-observer reproducibility (kappa values) was 0.76 and 0.7065, respectively. Agreement was slightly higher in the analysis of time-activity curves (0.767 and 0.731). Our results indicate that GER may be reproducibly analysed on scintigraphy by the same and different observers with varying levels of training. Its visualization is associated with reflux duration, volume and dilution factor of radioactivity.

Guidelines for evaluation and treatment of gastroesophageal reflux in infants and children: recommendations of the North American Society for Pediatric Gastroenterology and Nutrition

Gastroesophageal reflux (GER), defined as passage of gastric contents into the esophagus, and GER disease (GERD), defined as symptoms or complications of GER, are common pediatric problems encountered by both primary and specialty medical providers. Clinical manifestations of GERD in children include vomiting, poor weight gain, dysphagia, abdominal or substernal pain, esophagitis and respiratory disorders. The GER Guideline Committee of the North American Society for Pediatric Gastroenterology and Nutrition has formulated a clinical practice guideline for the management of pediatric GER. The GER Guideline Committee, consisting of a primary care pediatrician, two clinical epidemiologists (who also practice primary care pediatrics) and five pediatric gastroenterologists, based its recommendations on an integration of a comprehensive and systematic review of the medical literature combined with expert opinion. Consensus was achieved through Nominal Group Technique, a structured quantitative method. The Committee examined the value of diagnostic tests and treatment modalities commonly used for the management of GERD, and how those interventions can be applied to clinical situations in the infant and older child. The guideline provides recommendations for management by the primary care provider, including evaluation, initial treatment, follow-up management and indications for consultation by a specialist. The guideline also provides recommendations for management by the pediatric gastroenterologist. This document represents the official recommendations of the North American Society for Pediatric Gastroenterology and Nutrition on the evaluation and treatment of gastroesophageal reflux in infants and children. The American Academy of Pediatrics has also endorsed these recommendations. The recommendations are summarized in a synopsis within the article. This review and recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the management of all patients with this problem.

Standards for non-invasive methods for gastrointestinal motility: scintigraphy. A position statement from the Gruppo Italiano di Studio Motilità Apparato Digerente (GISMAD)

Scintigraphic techniques are well established methods to assess gastrointestinal transit patterns. The main advantages are represented by the possibility to evaluate, in a relatively non-invasive manner, the transit time of specific components of physiological meals as well as of some digestive secretions. These techniques are generally well accepted by the patients and results are largely not operator dependent. Their main limitation is the use of a radioisotope, that prevents repeated applications in all subjects and immediate exclusion of women of childbearing potential. Due to the high costs of these tests and the limited availability of Nuclear Medicine Departments, scintigraphic techniques should be reserved for well-selected patients. A review is made of the technical requirements and indications for scintigraphic tests currently available for clinical purposes (gastric emptying study, oesophageal transit time, evaluation of gastro-oesophageal reflux, intestinal and colonic transit time, evaluation of biliary motility and of duodenogastric reflux).

Patterns of food and acid reflux in patients with low-grade oesophagitis--the role of an anti-reflux agent

BACKGROUND

Food and acid have been shown to be refluxed independently of each other in healthy volunteers, and anti-reflux agents decrease the reflux of both parameters. Until now this phenomenon had not been studied in patients with low-grade oesophagitis, who are the group most likely to use anti-reflux medication.

AIM

To assess patterns of gastro-oesophageal reflux of acid and food in 12 ambulant patients with endoscopically proven oesophagitis of between grades I and II, but who were otherwise healthy. Also to assess the effectiveness of a single dose of an alginate-containing anti-reflux agent in controlling food and acid reflux in this patient group.

METHODS

Oesophageal pH monitoring and external ambulatory gamma detection were used to study food and acid reflux. A pH electrode was positioned 5 cm above the cardia and the gamma detector was positioned externally over the pH electrode. The patients then received a technetium-99m labelled meal designed to provoke reflux. Thirty minutes later the patients were given a 20 ml dose of alginate (Liquid Gaviscon), or 20 ml of tap water. Incidence of reflux was monitored for approximately 4 h from the end of the meal. Allocation to treatment group was randomized, with patients receiving the alternative treatment on the second study day after approximately a 7-day washout period.

RESULTS

The mean percentage time oesophageal pH remained below 4 was 16.3 min for the control group and 5.4 min for the treatment group (P = 0.03). Food reflux was detected 23.7% of the time in the control group compared to 12% of the time in the treatment group (P = 0.02). The anti-reflux agent was also successful in decreasing the number of events, but the duration of the reflux events was not significantly different.

CONCLUSIONS

Patients with grades I and II oesophagitis reflux food and acid independently, and are predominantly either food refluxers or acid refluxers, but not both. Liquid alginate decreases the number of both food and acid reflux events, but does not change their duration.

Pediatric gastrointestinal motility studies

Radionuclide studies for evaluating gastrointestinal transit in adults have been adapted for use in infants and children for assessing esophageal transit, gastroesophageal reflux, and gastric emptying. However, the measurement of small- and large-bowel transit times in these patients has been limited.

Recent advances in pediatric nuclear medicine

This review is devoted to some controversial topics in the field of pediatric nuclear medicine. In most cases, drug sedation can be avoided and the nuclear medicine procedure can be successfully achieved simply by taking the emotional life of the child into account. Factors such as past negative experiences (painful procedures, hospitalizations), unfamiliar environment (frightening examination room), physical aggressions related to the nuclear medicine procedure (intravenous injections, cystography), and the feeling of loss of parents' protection all contribute to the child's anxiety. People in charge of pediatric procedures should be adequately trained to be aware of these factors and to create the best environmental conditions to avoid unnecessarily frightening the child. Methods for measuring renal clearance in children are numerous. It is my aim to review the different methods proposed in the literature, including the nonradioisotopic methods, the reference radioisotopic methods, the various simplified algorithms using blood samples, and the gamma-camera methods. Gastroesophageal reflux scintigraphy is a well-established procedure for the detection of gastro-esophageal reflux in children. However, despite the numerous advantages of this technique, it has not gained wide acceptance in the field of pediatric gastroenterology. This review focuses mainly on the comparison between scintigraphy and pH metry. Finally, the applications of 99m technetium-hexamethylpropylenamine brain single photon emission computer tomography in the field of pediatric neurology are still under development; this part of the review is an attempt to summarize the real contribution of this technique.

Current applicability of scintigraphic methods in gastroenterology

Patients are often referred for evaluation of a wide range of GI complaints including dysphagia, abdominal pain, bloating, nausea, constipation or diarrhoea. Many are diagnosed with 'functional' disease when endoscopy or conventional radiological studies fail to identify an anatomic cause for the patient's symptoms. In such cases nuclear medicine offers non-invasive methods for objectively demonstrating disease involving different areas of the gastrointestinal tract. Increasingly scintigraphy is playing a primary role in the evaluation of patients with suspected acute cholecystitis, active gastrointestinal bleeding, gastroparesis, and small and large bowel motility disorders. In addition, it supplements other studies when results are inconclusive in diagnosing oesophageal dysmotility, gastro-oesophageal reflux, acalculous cholecystitis, and postoperative complications of gastrointestinal surgery.

Radionuclide detection of gastroesophageal reflux in children suffering from recurrent lower respiratory tract infection

Radionuclide gastro-esophageal scintigraphy was performed on 25 control and 183 children suffering from recurrent lower respiratory tract infection. Gastro-esophageal reflux (GER) of varying grades was observed in 135 patients. The severity of clinical symptoms in the patients was found to be directly related to the severity of reflux observed in the radionuclide study. In some patients an attempt was also made to quantitate GER by calculating the Gastro-esophageal reflux index. The results of the scintigraphic study were correlated with the results of the other commonly used and more conventional Barium swallow and fluoroscopy study. Gastro-esophageal scintigraphy was found to be much superior in terms of sensitivity, specificity and accuracy in detecting GER. It was also possible to objectively evaluate and monitor response to treatment following conservative or corrective surgical therapy using the radionuclide technique. The results of the study demonstrated a remarkably high incidence of GER in the patients. Whether GER is the cause of recurrent lower respiratory tract infection or not is difficult to establish firmly. But within the preview of the study the association seems to be very strong and cannot be easily ignored.

Observations on gastro-oesophageal reflux, central apnoea and heart rate in infants

Respiratory movements and heart rate were monitored continuously during the course of 2 h radionuclide studies to detect gastro-oesophageal reflux (GOR) in 22 infants following a milk feed. Twenty infants had GOR, to upper oesophageal/pharyngeal level in 19, and 17 had central apnoea between 3 and 15s. Prolonged central apnoea (greater than 20s) was not observed. Bradycardia, defined as a heart rate less than 80 beats/min for 10s or more, was observed in only 1 infant who did not have GOR. No correlation was found between the number or duration of reflux episodes and the frequency of respiratory pauses between 3 and 17s. When data from individual infants were examined a possible temporal relation between the occurrence of GOR and central apnoea was seen in only two infants; in each case, detailed examination suggested that apnoea was more closely associated with sleep than with GOR. Although the respiratory monitoring system did not include airflow sensors, the almost complete absence of bradycardia suggested that prolonged obstructive apnoeas did not occur. We conclude that any relation between GOR and central apnoeas less than 15 s is not of a direct cause/effect nature.

Vomiting and gastro-oesophageal reflux

During radionuclide scans in 82 infants and children gastro-oesophageal reflux extending to the upper oesophageal/laryngeal level was detected in 636 one minute frames. Only 61 (9.6%) of these frames were associated with vomiting, defined as the appearance of milk at the mouth. Thus the absence of vomiting does not preclude appreciable gastro-oesophageal reflux.

Evaluation of the gastrointestinal tract in the child: CT, MRI, and isotopic studies

The gastrointestinal radiologist no longer has to rely on indirect signs of extraluminal and solid organ pathology. With the use of the newer imaging modalities, including computed tomography, magnetic resonance imaging, and isotopic techniques, the entire abdomen and its contents can be directly visualized. Pathology, its extent and its effect on adjacent structures, can be readily appreciated.

The effect of various types of gastrostomy on the lower esophageal sphincter

Previous studies have demonstrated a cause and effect relationship between standard Stamm gastrostomy (SG) and subsequent gastroesophageal reflux (GER). To further investigate this clinical problem, three additional types of gastrostomy were evaluated in regard to their influence on the lower esophageal high pressure zone (LEHPZ). Twenty-three male cats were entered in the study weighing 2.6 to 3.6 kg. Baseline manometric studies of the LEHPZ were determined after ketamine anesthesia. In group I (n = 9), Witzel gastrostomy was performed over a 12 Fr catheter without fixation of the stomach to the anterior abdominal wall. In group II (n = 7), percutaneous gastrostomy was performed without fixation of the stomach to the anterior abdominal wall. In group III (n = 7), percutaneous gastrostomy was performed but the stomach was firmly fixed to the abdominal wall. LEHPZ pressures were then repeated 2 weeks postoperatively. Mean preoperative LEHPZ pressure for group I was 16.2 +/- 3.72 mmHg, group II was 16.5 +/- 6.91 mmHg, and group III was 18.3 +/- 5.59 mmHg. Mean postoperative pressure for group 1 was 14.7 +/- 4.26 mmHg, group II was 16.5 +/- 5.77 mmHg, and group III was 10.8 +/- 3.97 mmHg. LEHPZ pressure was similar preoperatively and postoperatively in groups I and II but was significantly decreased postoperatively (P less than .01) in group III. Contrast studies demonstrated maintenance of the angle of His in group 1 and II and alteration of the angle of His in group III. Gastrostomy associated with fixation of the stomach to the anterior abdominal wall results in decreased LEHPZ pressures. This predisposes the subject to GER.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastric emptying with gastro-oesophageal reflux

The time taken for gastric emptying of a liquid (milk) or a semi-liquid (pudding) meal was evaluated in 477 infants and children. These patients were referred for suspected gastro-oesophageal reflux and underwent gastro-oesophageal scintigraphy, prolonged oesophageal pH study, manometric evaluation of the lower oesophageal sphincter pressure, and fibreoptic endoscopy. No difference in gastric emptying was observed in children aged under 3 years, regardless of the presence or absence of the gastro-oesophageal reflux, the pressure of the lower oesophageal sphincter, or the presence of oesophagitis. In children over 6 years, however, gastric emptying was significantly delayed in those presenting with reflux compared with those without reflux; in children over 3 years there was slower gastric emptying in those with a decreased lower oesophageal sphincter pressure compared with those with higher pressure and in those with overt oesophagitis compared with those without oesophagitis. This study suggests that gastro-oesophageal reflux is more severe in childhood than in infancy, probably due to more complex motor disorders affecting the gastric fundus as well as lower oesophageal sphincter function.