Shreya Raja

Comprehensive Radionuclide Esophagogastrointestinal Transit Study: Methodology, Reference Values, and Initial Clinical Experience

A radionuclide methodology and reference values have been developed for a single gastrointestinal transit study including esophageal transit, liquid and solid gastric emptying, and small- and large-bowel transit, using 111In-diethylenetriaminepentaacetic acid (DTPA) with the standardized 99mTc-labeled solid meal. Methods: Eighteen healthy subjects and 18 patients were investigated. The esophageal transit study was performed with 3.7 MBq (0.1 mCi) of 111In-DTPA in 15 mL of water. A liquid-only 30-min gastric-emptying study followed, with ingestion of 3.7 MBq (0.1 mCi) of 111In-DTPA in 300 mL of water. Then, a simultaneous solid–liquid emptying study was acquired after ingestion of a solid 99mTc-sulfur colloid–labeled meal and 7.4 MBq (0.2 mCi) of 111In-DTPA in 120 mL of water. Images were acquired intermittently for 4 h. Additional 111In images were acquired at 5 and 6 h to measure small-bowel transit, and at 24, 48, and 72 h for large-bowel transit. Results: Reference values were determined for esophageal transit (transit time, percentage emptying at 10 s), liquid-only gastric emptying (emptying half-time), liquid and solid emptying in a dual-phase solid–liquid study (emptying half-time and percentage emptying at 1, 2, 3, and 4 h), small-bowel transit index (percentage transit to ileocecal valve at 6 h), and colonic transit (geometric center and percentage colonic emptying) at 24, 48, and 72 h. Results from the first 18 patients found abnormal transit in 72% (13/18); clinical management changed in 61% (11/18). Conclusion: We have developed a radionuclide methodology and derived reference values for a comprehensive gastrointestinal transit study using 111In-DTPA with the standardized 99mTc-labeled solid meal. Our initial clinical experience suggests clinical value.

Mo1290 Intrapyloric Pressures (IPP) Are Elevated in Gastroparesis and Reliably Predict Scintigraphic Meal Emptying

Intra-Operative Electrophysiological and Interstitial Cell of Cajal Findings in Patients With the Symptoms of Gastroparesis Archana Kedar, Thomas L. Abell, Cheryl E. Bernard, Gianrico Farrugia, Christopher J. Lahr, William L. Hasler, Kenneth L. Koch, Richard W. McCallum, Linda Anh B. Nguyen, Henry P. Parkman, Pankaj J. Pasricha, Irene Sarosiek, William J. Snape, Aynur Unalp, James Tonascia, Jose Serrano, Frank A. Hamilton

Mo2092 Wireless Motility Capsule Alters Diagnosis and Affects Clinical Management in Patients With Suspected Gastrointestinal Dysmotility

BACKGROUND: The wireless motility capsule (WMC) is a novel device which is FDAapproved for the evaluation of suspected gastroparesis and slow-transit constipation. WMC provides information regarding pH, temperature and pressure throughout the GI tract and can be used to assess regional and whole-gut transit and pressure patterns. Several studies have validated WMC findings versus standard motility testing; however, there is limited data examining how WMC findings affect clinical care. AIMS: Aims were to investigate (1) the diagnostic yield of WMC in patients with suspected dysmotility and (2) change in clinicalmanagement afterWMC testing, includingmedication changes, referrals for additional diagnostic tests, and outside referrals. METHODS: We retrospectively reviewed 51 consecutive patients referred for WMC at a single, academic tertiary care center from April 2009 to October 2012. Information on demographics, past medical and surgical history, indications for WMC, WMC transit times, and relevant diagnostic studies were collected. Changes in clinical management at the first clinic visit after WMC testing were identified. Patients were excluded if WMC testing was incomplete or if no follow-up information was available. RESULTS: Patient characteristics including demographics and indications are summarized in Table 1. Results of positive WMC testing are summarized in Table 2A. Pan-GI dysmotility was present in 53% of patients with positive WMC testing. Effects of WMC results on diagnosis and management are summarized in Table 2B. Medication changes were more commonly seen in patients with an abnormal WMC test and included the addition or removal of prokinetics, antibiotics, herbal supplements, and neuromodulators. There were no statistically significant differences in additional imaging studies and referrals between the two groups. Referrals to non-GI providers included psychiatry, surgery, nutrition, acupuncture, and biofeedback. The presence of existing psychiatric comorbidities was also similar between groups. Of note, 80% of patients had other diagnostic studies obtained concurrently with WMC testing; however, attempts were made to isolate clinical changes made from WMC results specifically. CONCLUSIONS:WMC affects clinical management in the majority of patients referred for suspected dysmotility. Alteration in diagnosis was frequent, and change in medication was made for the majority of patients with abnormal WMC testing. Pan-GI dysmotility was common in patients referred for suspected regional dysmotility. Normal WMC testing changed clinical management in over 50% of cases. Our results suggest that WMC testing impacts patient care by altering diagnosis and clinical management. Prospective studies are needed to determine how WMC may affect long-term outcomes. Table 1. Patient Characteristics (N=51)

Tu1978 LES Pressures Are Inversely Correlated to Esophagogastric Junction Diameter and Cross-Sectional Area in Achalasia

G A A b st ra ct s each method are shown in Table 1. Among these candidate methods, optimal discrimination from type I achalasia was achieved using the 4s-IRP method and receiver operating curve analysis revealed an optimal threshold %EGJR to be (<40%, sensitivity 100%, specificity 88%). The Figure shows %EGJR data using the 4s-IRP method for all patients compared to controls. As a single metric, the IRP exhibited superior discriminative performance to %EGJR among diagnoses. However, in certain instances, %EGJR was a useful secondary metric. Specifically, 100%(25 patients) of the Jackhammer group, a classification which may present with an elevated IRP and have an erroneous diagnosis of type III achalasia, fell within the normative range for percent EGJ relaxation. However, with low baseline EGJ pressure, %EGJR performed poorly in discriminating between patients with absent peristalsis(24/25 of whom had a collagen vascular disease or reflux disease) and type I achalasia. Conclusions: This study discounts the viability of the %EGJR metric as a stand-alone tool for assessing the adequacy of EGJ relaxation within the framework of the CC of motility disorders. However, there may be a supplementary role for this metric in identifying borderline cases of achalasia from mechanical causes of EGJ outflow obstruction and in differentiating Jackhammer cases from type III achalasia.

Mo1308 Liquid and Solid Gastric Scintigraphy Are Frequently Abnormal in Symptomatic Patients With Systemic Sclerosis

Background: Different mechanisms underlie gastroparesis. Patients with gastroparesis (GP) commonly have gastric dysrhythmias such as tachygastria. A subset of patients with GP has normal 3 cpm gastric myoelectrical activity with increased amplitude, suggesting normal corpus-antral electrocontractile function and the possibility of pyloric dysfunction. Our Aim was to assess the effect of pyloroplasty on symptoms, weight and gastric emptying in patients with GP, normal 3 cpm electrical activity and positive response to Botulinum A toxin injection or balloon dilation of the pylorus. Methods: Clinical databases were reviewed to identify patients with GP measured by scintigraphy (EggBeaters meal), normal 3 cpm gastric myoelectrical activity measured by electrogastrogram recording with water load test, and positive symptom response after Botulinum A injection or balloon dilation of the pylorus. Endoscopy excludedmechanical obstruction at the pylorus. Eighteen patients were identified; four underwent pyloroplasty; these patients also had gastric emptying and myoelectrical recordings 57 months after operation. Results: The four patients were women, ages 29 to 41 yrs. Three patients had idiopathic and one had diabetic GP. Nausea, vomiting and early satiety were the dominant symptoms. Percentage of meal retained at 4 hrs. was 24%, 34% and 96% (normal <9%) and one patient had 80% retained at 2 hr. (normal <60%). Botulinum A toxin injections (100 mg) ranged from 2-12 and balloon dilations ranged from 5-9. Pyloroplasty operations were performed laparoscopically and without complications. Patients reported improvement in nausea, vomiting and early satiety at their post-pyloroplasty clinic visits. Three patients gained 1, 5 and 20 pounds and one lost 7 pounds after pyloroplasty. Gastric emptying tests improved to normal in the three patients with idiopathic GP (% retained at 4 hrs. was 9%, 7%, and 1%) and improved from 96% to 27 % retained at 4 hrs. in the patient with DG. Water load volumes ingested before and after pyloroplasty were 481 ml and 325 ml, respectively. After pyloroplasty two patients had mixed gastric dysrhythmia and two had tachygastria after the water load test. Conclusion: Gastric emptying rates normalized or improved and symptoms decreased after pyloroplasty in carefully selected patients with GP, normal 3 cpm myoelectrical activity and positive pre-operative responses to pyloric therapies. These findings indicate that neuromuscular dysfunction of the pylorus results in functional obstructive GP, a key pathophysiological mechanism in this subset of GP.