Complete Emptying Research Articles

Complicated Urinary Tract Infection in the Geriatric Population

Complicated urinary tract infection (UTI) is a common problem in the geriatric population. The major complicating factors are frequent use of indwelling catheters and disorders that inhibit complete emptying of the bladder. Infection with antimicrobial-resistant, gram-negative bacilli (GNB) is much more common in those with complicated infection than those with uncomplicated infection. Nitrofurantoin and fosfomycin are the oral agents most likely to retain activity against the very resistant GNB, but Proteus species and Pseudomonas are resistant to nitrofurantoin. The polymyxins and tigecycline are the parenteral agents most likely to retain activity against these organisms, but low serum and urine levels are problematic for tigecycline. Bacteremia is common and the infection may be life-threatening in the presence of pyelonephritis with obstructive uropathy, renal abscess, perinephric abscess, emphysematous pyelonephritis, or emphysematous cystitis. With complicated pyelonephritis, imaging studies are critical and urological consultation and intervention may be necessary, especially if obstructive uropathy or any of the above life-threatening complications is present. With complicated lower tract infection, the goal is relief of symptoms.

Voiding dysfunction due to detrusor underactivity: an overview.

Detrusor underactivity (DUA) is defined as a voiding contraction of reduced strength and/or duration, which prolongs urination and/or prevents complete emptying of the bladder within a 'normal' period of time. This issue is associated with voiding and postmicturition urinary symptoms, and can predispose to urinary infections and acute urinary retention. The aetiology of DUA is influenced by multiple factors, including ageing, bladder outlet obstruction, neurological disease, and autonomic denervation. The true prevalence of this condition remains unknown, as most data come from referral populations. Urodynamic testing is used to diagnose the condition, either by assessing the relationship between bladder pressures and urinary flow, or by interrupting voiding to measure detrusor pressure change under isovolumetric conditions. Current treatments for DUA have poor efficacy and tolerability, and often fail to improve quality of life; muscarinic receptor agonists, in particular, have limited efficacy and frequent adverse effects. Bladder emptying might be achieved through Valsalva straining, and intermittent or indwelling catheterization, although sacral nerve stimulation can reduce dependency on catheterization. Novel stem-cell-based therapies have been attempted; however, new drugs that increase contractility are currently largely conceptual, and the complex pathophysiology of DUA, difficulty achieving organ specificity of treatment, the limited availability of animal models, and the subjective nature of current outcome measures must be addressed to facilitate the development of such agents.

Gas emissions from liquid dairy manure: complete versus partial storage emptying

When manure slurry is removed from storages for land application, there is often ‘aged’ manure that remains because the storages are not completely emptied. Aged manure may act as an inoculum and alter subsequent methane (CH4), nitrous oxide (N2O) and ammonia (NH3) emissions when fresh manure is added to the system, compared to an empty storage that is filled with fresh manure. Completely emptying manure storages may be a practice to decrease gas emissions, however, little pilot-scale research has been conducted to directly quantify the inoculum effect. Therefore, we compared CH4, N2O, and NH3 emissions from three pilot-scale slurry tanks (~10.5 m3 each) filled with a mixture of fresh manure and an inoculum of previously stored manure (i.e., partial emptying) to three tanks that contained only fresh manure (i.e., complete emptying). Gas fluxes were continuously measured over 155 d of warm season storage using flow-through steady-state chambers. The absence of an inoculum significantly reduced CH4 emissions by 56 % compared to partially emptied (inoculated) tanks, while there was no difference in N2O emissions. There was a significant 49 % reduction in greenhouse gas (GHG) emissions because the overall budget (as CO2-eq) was dominated by CH4. Complete manure storage emptying could be an effective GHG mitigation strategy; however, NH3 emissions were significantly higher from un-inoculated tanks due to slower crust formation. Therefore additional NH3 abatement should be considered.

Intragastric Volume Changes after Intake of a High-Caloric, High-Fat Standard Breakfast in Healthy Human Subjects Investigated by MRI

The aim of this magnetic resonance imaging (MRI) study was to investigate gastric emptying after intake of a high-caloric and high-fat standard meal as recommended by FDA and EMA for food-effect bioavailability and fed bioequivalence studies. Twelve healthy human subjects (7 male, 5 female) received the standard meal after an overnight fast. MRI was performed before as well as 15, 25, 35, 45, 55, 65, 105, 195, 275, and 375 min after meal intake using strong T2-weighted sequences and chemical shift imaging. In addition, 30 min after the beginning of meal intake subjects ingested 240 mL of water representing the recommended coadministration of water during drug intake. Gastric content volume was assessed using T2-weighted images, and fat fraction was estimated using a calculation of fat fraction in chemical shift imaging. In addition, the existence of a mechanism allowing fast gastric emptying of water in the fed state was investigated. After a lag phase of 50-90 min, gastric content volume decreased constantly with a rate of 1.7 mL/min. The water ingested 30 min after the start of the meal intake directly reached the antrum and subsequently was emptied quickly from the human stomach. Complete gastric emptying within 6 h was observed in only one out of 12 subjects. The fat fraction of the intragastric chyme decreased from 9.5% directly after meal intake to 6.3% at the end of the experiments. Moreover, the fat fraction in fundus was significantly higher compared to the antrum. This study contributes fundamental data for the assessment of food effects of solid oral dosage forms.

First description of milk flow traits in Tunisian dairy dromedary camels under an intensive farming system

In order to evaluate milking ability in dromedary camels, 124 milk flow curves were registered during morning milking of 20 dairy Maghrebi dromedary camels. Animals were in lactations 1-8, were 6-19 years old and were 4-15 months of their current lactation. Milk flow curves were recorded using an electronic milk flow meter (Lactocorder®). Milk flow curves were classified in three typical patterns: type 1 represents curves with one high and short peak of milk flow; type 2 represents curves with a moderate mean milk flow rate during a large plateau phase; and type 3 represents curves with lower mean milk flow rate and a relatively longer milking duration. The ratio of the different milk flow patterns in the population evaluated was 40:38:22% for types 1, 2 and 3, respectively. The highest milk yield per milking, average and peak milk flow were observed in camels with type 1 curves (4·24kg, 1·49 and 3·54kg/min, respectively) followed by type 2 animals (3·30kg, 1·12 and 2·12kg/min, respectively) and lastly type 3 curves (2·34kg, 0·65 and 1·23kg/min, respectively). This study confirmed that a major proportion of dromedary camels have a suitable machine milking ability. Nevertheless, our results suggest that pre-stimulation and improving the milking process may improve milking efficiency and guarantee a more complete and rapid emptying of the udder.

Temporal Kinetics and Quantitative Analysis of Cryptococcus neoformans Nonlytic Exocytosis

Cryptococcus neoformans is a facultative intracellular pathogen and the causative agent of cryptococcosis, a disease that is often fatal to those with compromised immune systems. C. neoformans has the capacity to escape phagocytic cells through a process known as nonlytic exocytosis whereby the cryptococcal cell is released from the macrophage into the extracellular environment, leaving both the host and pathogen alive. Little is known about the mechanism behind nonlytic exocytosis, but there is evidence that both the fungal and host cells contribute to the process. In this study, we used time-lapse movies of C. neoformans-infected macrophages to delineate the kinetics and quantitative aspects of nonlytic exocytosis. We analyzed approximately 800 macrophages containing intracellular C. neoformans and identified 163 nonlytic exocytosis events that were further characterized into three subcategories: type I (complete emptying of macrophage), type II (partial emptying of macrophage), and type III (cell-to-cell transfer). The majority of type I and II events occurred after several hours of intracellular residence, whereas type III events occurred significantly (P < 0.001) earlier in the course of macrophage infection. Our results show that nonlytic exocytosis is a morphologically and temporally diverse process that occurs relatively rapidly in the course of macrophage infection.

O042 Coronary sinus filling and emptying time: a new parameter to assess coronary microcirculation by a simple angiographic frame count

Introduction: Functional assessment of coronary microcirculation has been difficult for various reasons. Nuclear imaging, PET scan have been used to assess the viability of microcirculation and myocyte perfusion . Digital frame counting of coronary angiograms (CAG) has been used to measure the transit time of dye across the coronary artery . Myocardial blush scores is an subjective method to assess myocardial perfusion based on visual acuity .There is no simple method available to assess the integrity of the coronary microcirculation. The transit time between the coronary artery to the coronary sinus(CS) would indicate the microcirculatory time. Video images obtained during routine CAG provides us an opportunity to measure this time Objectives: We hypothized , coronary sinus filling time(CFT) , coronary sinus emptying time(CET), Coronary sinus emptying velocity(CEV) will give a simple index of micro circulatory state. Methods: Patients who were undergoing routine CAG in our cath lab were the subjects of the study . Twenty normal angiograms with well delineated CS were analysed. ( Ten without CAD and ten with positive stress test). CAG was done and assessed with Philips digital Integris workstation. CAG was performed with 12.5 frames/sec. Coronary sinus filling time(CFT) was estimated by the difference between the frames of maximum LAD system opacification to maximal opacificaton of CS . Coronary sinus emptying time (CET)was the difference in frame count between maximal visualization of CS to complete emptying of CS. The Coronary sinus emptying velocity (CEV) was calculated by estimating the time taken for the dye to traverse two reference points across CS. The normal values were defined. Results:

Síndrome de estenose pilórica por adenocarcinoma de piloro

We present a case of primary malignant pylorus neoplasia, emphasizing its rarity, the difficulty of diagnosis and the importance of an adequate prepare before the endoscopic procedure. Literature shows that tumors compromising the first, third and fourth segments of duodenum are rare, especially those of the pyloric area, representing only 0.35% of all malignant tumors of the gastrointestinal tract. Adenocarcinoma is the most common histological type, representing 50% of all malignant neoplasias at this site. The most common symptoms are weight loss, nausea, vomiting, abdominal pain, abdominal mass, sudden changes in intestinal habits and iron deficiency anemia secondary to chronic intestinal hemorrhage. Survival after five years is only 18%. We report a case of a seventy-one year-old male referring early satiety, epigastric pain, retrosternal burning and dyspepsia, with unspecific results in complementary exams, since complete gastric emptying was not achieved. As symptoms worsened, the patient was submitted to laparotomy, with identification of gastric dilation and severe pyloric stenosis, macroscopically suggesting malignancy. The chosen procedure was a subtotal gastrectomy. Adjuvant radiotherapy and chemotherapy were not used. The patient is been followed-up without tumor recurrence so far.

Laparoscopic and robot‐assisted continent urinary diversions (Mitrofanoff and Yang‐Monti conduits) in a consecutive series of 15 adult patients: the Saint Augustin technique

To present a series of 15 laparoscopic and robot-assisted Mitrofanoff and Yang-Monti vesicostomies in an adult population, and to assess the feasibility and safety of these minimally invasive approaches. Between 2009 and 2012, 15 patients underwent laparoscopic (n = 11) or robot-assisted (n = 4) construction of vesicostomy by a single surgeon (D.R.): Mitrofanoff appendicovesicostomy (n = 11) or double Yang-Monti ileal conduit (n = 4). Fourteen patients underwent concomitant augmentation enterocystoplasty. Indications for surgery included neurogenic bladder (n = 11) and urethral dysfunction (n = 4). The patients were evaluated postoperatively using cystography. Quality of life (QoL) was evaluated using an internally developed questionnaire. All surgeries were successfully completed with no conversions. Operating time was always <5 h. The mean estimated blood loss was 150 mL and the mean follow-up was 22 months. Early postoperative complications included deep retrovesical abscess (n = 2) and upper urinary tract infections (n = 4), and one patient had peri-operative cardiac failure. Late postoperative complications included stomal stenosis (n = 2), persistent low-pressure bladder incontinence (n = 1) and recurrent infections (n = 1). Surgical excision of the conduit was necessary in one patient. Postoperatively, patients showed complete bladder emptying and no leak on follow-up cystography. According to our QoL questionnaire, 13/15 patients did not regret the surgery. While a longer follow-up is needed to assess the durability of our results, this series shows that the laparoscopic and robot-assisted approaches for the construction of continent urinary diversions are feasible and safe in an adult population.

Catheter length preference in wheelchair-using men who perform routine clean intermittent catheterization

Prospective, unblinded, multicenter, randomized, controlled, cross-over study assessing user preference and ease of use characteristics of two gel intermittent catheters in 81 self-catheterizing wheelchair-using men. To evaluate the male user's preference between a 30-cm and a 40-cm intermittent catheter (Apogee Intermittent Catheter, Hollister Incorporated, Libertyville, IL, USA) regarding the ease of insertion and removal, ability to control the catheter during insertion, bladder emptying confidence and ease of draining urine into a receptacle or connecting to a urine bag. Multiple institutions in the United States. Subjects were randomized to order of catheter use, using both 10 test catheters (30-cm) and 10 control catheters (40 cm). All catheters were 12 or 14 French and identical in design and composition, except length. Safety was assessed during the entire study period regarding adverse events (AE) and adverse device events (ADE). Subjects evaluated their ease of use characteristics after each catheter use and final catheter preference. Subjects preferred the Apogee 40-cm intermittent catheter (91.4%) over the 30-cm length (8.6%). The preference was due to subject confidence of complete bladder emptying (70%), more satisfactory length (74%) and easier to drain into a receptacle (58%) with a portable urinal being the most utilized (37%), followed by toilet (35%). The only AE/ADE reported was minor urethral bleeding in one subject and minor pain in another subject, both with the 30-cm catheter. None were reported with the 40-cm catheter. The Apogee 40-cm catheter was the preferred intermittent catheter due to subject confidence in bladder emptying, ease of catheter manipulation and the ease of draining urine into a receptacle.

Colorectal transport during defecation in subjects with supraconal spinal cord injury

Clinical study. To explore how supraconal spinal cord injury (SCI) affects colorectal emptying at defecation. Further, to relate findings to subject symptomatology expressed by bowel function scores and gastrointestinal transit time (GITT). Aarhus University Hospital, Denmark. Colorectal contents were marked by oral intake of (111)In-coated resin pellets. Movement of stools at defecation was assessed by comparing scintigrams performed before and just after defecation. Results from 15 subjects with SCI (14 males, median age=47 years (range: 22-74 years), SCI level: C5-Th9) were compared with those from 16 healthy volunteers (12 males, median age=31 years (range: 24-42 years)). Bowel symptoms were described from standard symptom scores, and GITT was assessed by radiopaque markers. Median emptying at defecation was 31% of the rectosigmoid (range: 0% to complete emptying of the rectosigmoid and 49% of the descending colon) in subjects with SCI and 89% of the rectosigmoid (range: 53% to complete emptying of the rectosigmoid and the descending colon, and 3% of the transverse colon) in the control group (P<0.01). Colorectal emptying at defecation was associated with the St Mark's fecal incontinence score (P=0.02) but not with the Cleveland constipation score (P=0.17), the neurogenic bowel dysfunction score (P=0.12) or GITT (P=0.99). Supraconal SCI results in significantly reduced emptying of stools at defecation. This is independent of changes in GITT.

PWE-001 The Impact of Colonic Resection for Neoplasia on Functional outcomes and Related Quality of Life: a Case-Controlled Study

Introduction AimFunctional outcomes after elective colectomy (right, left or sigmoid) for neoplasia are poorly reported in the literature. This study evaluates bowel function and related quality of life in patients...

Automated high precision secondary pH measurements

A new setup for high precision, automated secondary pH measurements together with a reference measurement procedure has been developed and tested in interlaboratory comparisons using buffers pH 4.005, pH 7.000, and pH 10.012 at 25 °C and 37 °C. Using primary buffers as standards, a standard uncertainty in pH better than 0.005 can be reached. The central measuring device is a one piece, thermostatted cell of PFA (perfluoroalkoxy) with a built-in Hamilton(®) Single Pore™ Glass electrode. Due to its flow-through principle this device allows pH measurements with low consumption of measurement solutions. The very hydrophobic and smooth PFA as construction material facilitates complete emptying of the cell. Furthermore, the tempering unit affords very precise temperature control and hence contributes to the low target uncertainty of the produced secondary buffer solutions. Use of a symmetric measurement sequence and the two point calibration was sufficient to reach high precision and accuracy.

Concept design studies on the ITER HNB Duct Liner

The Duct Liner for the International Thermonuclear Experimental Reactors (ITER) Heating Neutral Beam (HNB) system is a key component in the beam transport system. Power loading on the top and bottom beam scraping panels of the Duct Liner occurs primarily due to direct interception of the HNB and it is highest at the extreme steering angles of the beam. Furthermore, power loading due to direct interception is dependent on the size and orientation of the scraper panels with respect to the neutral beam axis. This paper outlines the design features of the proposed Duct Liner and describes the analysis performed to optimize the compatibility of the top and bottom scraper panels (also known as Duct Liner Modules) with a normal beam operation scenario. Thermo-mechanical analyses have been performed to validate the design of Duct Liner Modules incorporating deep-drilled cooling technology with a peak power density of 1.2MW/m2 and incident power of 0.27MW, and also to verify its conformity with ITER structural design criteria. Furthermore, numerical simulations of the transient draining procedure were performed by using a one-dimensional thermo-hydraulic code to demonstrate complete emptying of the proposed parallel-layout cooling circuit without any reliance on conventional gravity draining.

Visualization of embolism formation in the xylem of liana stems using neutron radiography.

Cold neutron radiography was applied to directly observe embolism in conduits of liana stems with the aim to evaluate the suitability of this method for studying embolism formation and repair. Potential advantages of this method are a principally non-invasive imaging approach with low energy dose compared with synchrotron X-ray radiation, a good spatial and temporal resolution, and the possibility to observe the entire volume of stem portions with a length of several centimetres at one time. Complete and cut stems of Adenia lobata, Aristolochia macrophylla and Parthenocissus tricuspidata were radiographed at the neutron imaging facility CONRAD at the Helmholtz-Zentrum Berlin für Materialien und Energie, with each measurement cycle lasting several hours. Low attenuation gas spaces were separated from the high attenuation (water-containing) plant tissue using image processing. Severe cuts into the stem were necessary to induce embolism. The formation and temporal course of an embolism event could then be successfully observed in individual conduits. It was found that complete emptying of a vessel with a diameter of 100 µm required a time interval of 4 min. Furthermore, dehydration of the whole stem section could be monitored via decreasing attenuation of the neutrons. The results suggest that cold neutron radiography represents a useful tool for studying water relations in plant stems that has the potential to complement other non-invasive methods.

Wireless Motility Capsule Test in Children with Upper Gastrointestinal Symptoms

To compare scintigraphic gastric emptying and antroduodenal manometry (ADM) studies with the wireless motility capsule test in symptomatic pediatric patients. Patients aged 8-17 years with severe upper gastrointestinal symptoms (ie, nausea, vomiting, retching, abdominal pain) referred for ADM were recruited. A standardized protocol for ADM was used. On a different day, participants were given a standardized meal and then swallowed the wireless motility capsule. A wireless receiver unit worn during the study recorded transmitted data. If not performed previously, a 2-hour scintigraphic gastric emptying study was completed at the time of ADM testing. A total of 22 patients were recruited, of whom 21 had complete scintigraphic gastric emptying study data and 20 had complete ADM data. The wireless motility capsule test had 100% sensitivity and 50% specificity in detecting gastroparesis compared with the 2-hour scintigraphic gastric emptying study. The wireless motility capsule test detected motor abnormalities in 17 patients, compared with 10 detected by ADM. Dichotomous comparison yielded a diagnostic difference between ADM and the wireless motility capsule test (P<.01). Migrating motor complexes were recognized in all patients by both ADM and the wireless motility capsule test. The wireless motility capsule test was well tolerated in all patients, and there were no side effects. In symptomatic pediatric patients, the wireless motility capsule test is highly sensitive compared with scintigraphic gastric emptying studies in detecting gastroparesis, and seems to be more sensitive than ADM in detecting motor abnormalities.

Free Energy Barriers to Evaporation of Water in Hydrophobic Confinement

We use umbrella sampling Monte Carlo and forward and reverse forward flux sampling (FFS) simulation techniques to compute the free energy barriers to evaporation of water confined between two hydrophobic surfaces separated by nanoscopic gaps, as a function of the gap width, at 1 bar and 298 K. The evaporation mechanism for small (1 × 1 nm(2)) surfaces is found to be fundamentally different from that for large (3 × 3 nm(2)) surfaces. In the latter case, the evaporation proceeds via the formation of a gap-spanning tubular cavity. The 1 × 1 nm(2) surfaces, in contrast, are too small to accommodate a stable vapor cavity. Accordingly, the associated free energy barriers correspond to the formation of a critical-sized cavity for sufficiently large confining surfaces, and to complete emptying of the gap region for small confining surfaces. The free energy barriers to evaporation were found to be of O(20kT) for 14 Å gaps, and to increase by approximately ~5kT with every 1 Å increase in the gap width. The entropy contribution to the free energy of evaporation was found to be independent of the gap width.

Barium proctography vs magnetic resonance proctography for pelvic floor disorders: a comparative study

Accurate and reliable imaging of pelvic floor dynamics is important for tailoring treatment in pelvic floor disorders; however, two imaging modalities are available. Barium proctography (BaP) is widely used, but involves a significant radiation dose. Magnetic resonance (MR) proctography allows visualization of all pelvic midline structures but patients are supine. This project investigates whether there are measurable differences between BaP and MR proctography. Patient preference for the tests was also investigated. Consecutive patients referred for BaP were invited to participate (National Research Ethics Service approved). Participants underwent BaP in Poole and MR proctography in Dorchester. Proctograms were reported by a consultant radiologist with pelvic floor subspecialization. A total of 71 patients were recruited. Both tests were carried out on 42 patients. Complete rectal emptying was observed in 29% (12/42) on BaP and in 2% (1/42) on MR proctography. Anismus was reported in 29% (12/42) on BaP and 43% (18/42) on MR proctography. MR proctography missed 31% (11/35) of rectal intussusception detected on BaP. In 10 of these cases no rectal evacuation was achieved during MR proctography. The measure of agreement between grade of rectal intussusception was fair (κ=0.260) although MR proctography tended to underestimate the grade. Rectoceles were extremely common but clinically relevant differences in size were evident. Patients reported that they found MR proctography less embarrassing but harder to empty their bowel. The results demonstrate that MR proctography under-reports pelvic floor abnormalities especially where there has been poor rectal evacuation.

V538 ROBOT-ASSISTED PYELOPLASTY IN A PELVIC KIDNEY

You have accessJournal of UrologyPediatrics1 Apr 2012V538 ROBOT-ASSISTED PYELOPLASTY IN A PELVIC KIDNEY Frank J. Penna, Wooju Jeong, and Jack S. Elder Frank J. PennaFrank J. Penna Detroit, MI More articles by this author , Wooju JeongWooju Jeong Detroit, MI More articles by this author , and Jack S. ElderJack S. Elder Detroit, MI More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.612AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The role of robot-assisted laparoscopic surgery is rapidly expanding, particularly within the field of pediatric urology. Various techniques have been shown to be feasible and as equipment and techniques improve, more complex reconstructive procedures may be attempted. For the current application, this surgical technique demonstrates the versatility of the robotic surgical system with variations in both patient size and anatomy. We report a robot-assisted procedure for a patient with an ectopically located pelvic kidney. METHODS The patient is an 11-month-old boy who was initially referred for urological evaluation at 2 weeks of age for prenatally detected hydronephrosis in a pelvic kidney. On postnatal work-up, the diagnosis of high-grade ureteropelvic junction obstruction was confirmed. The patient was a candidate for surgical intervention. The procedure began with cystoscopy, bilateral retrograde pyelography and left ureteral stent placement. A left retrograde pyelogram revealed a left-sided hydronephrotic kidney in the pelvis, just right of the midline. Using a tag, the location of the pelvic kidney was identified and labeled on the patient's abdomen to assist in directing proper port placement for the robot-assisted pyeloplasty. RESULTS The patient tolerated the procedure well. There were no complications. The patient was discharged on postoperative day 1 after adequate pain control without intravenous pain medication, return of bowel function, and complete bladder emptying. Follow-up ultrasound was normal. CONCLUSIONS Robot-assisted pyeloplasty is a safe and viable option for patients with an ectopically located pelvic kidney. The use of retrograde pyelography is essential in localizing the pertinent anatomy and for proper port placement and docking. The benefits of this procedure are manifold: patients are discharged sooner, the procedure is safe and efficacious and also offers benefits associated with minimally invasive surgery: less pain, morbidity with a potentially rapid recovery. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e221 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Frank J. Penna Detroit, MI More articles by this author Wooju Jeong Detroit, MI More articles by this author Jack S. Elder Detroit, MI More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Assessment of gastric emptying and duodenal motility upon ingestion of a liquid meal using rapid magnetic resonance imaging

Gastric emptying is achieved by co-operation between gastric and duodenal motor activity. Therefore, evaluation of gastric emptying and its associated mechanisms would benefit clinical therapy as well as medical research. Healthy volunteers underwent rapid magnetic resonance imaging (MRI) of the abdomen along the coronal plane after ingestion of a liquid meal. The gastric fundal and duodenal areas were quantified semi-automatically by self-developed segment software. The average gastric fundal area determined by the serosal end in 40 sequential images was reduced to ∼81% 30 min after and to ∼70% 60 min after ingestion of a liquid meal. The average duodenal area also decreased to ∼86% after 30 min and to 83% after 60 min. In contrast, changes in the centre of gravity increased to about fivefold after 30 min and to about threefold after 60 min. The mean velocity of the duodenal wall mimicked changes in the centre of gravity. The application of metoclopramide, a dopamine D(2) receptor antagonist, accelerated gastric emptying, presumably due to facilitated duodenal activity even immediately after liquid meal ingestion. The ingestion of water caused fast gastric emptying in 30 min, accompanied by high duodenal motility, but it ceased after 60 min, presumably reflecting complete gastric emptying. A rapid MRI scan visualized the association between gastric emptying and duodenal motility that could be modified by calories and dopaminergic neurotransmission. Changes in the centre of gravity and mean velocity of the duodenal wall appear to quantify the motility obtained from cine MRI accurately.