Candy Hofmann
Medical College of Wisconsin
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Gastroenterology | 1995
Reza Shaker; Mary M. Milbrath; Junlong Ren; Robert J. Toohill; Walter J. Hogan; Qun Li; Candy Hofmann
BACKGROUND & AIMS A variety of otolaryngological abnormalities have been attributed to the contact of gastroesophageal refluxate with respective structures of the aerodigestive tract. The aim of this study was to determine and compare the pharyngoesophageal distribution of gastric acid refluxate between patients with proven laryngitis attributed clinically to gastroesophageal reflux and three control groups. METHODS An ambulatory 24-hour simultaneous three-site pharyngoesophageal pH monitoring technique was used to measure reflux parameters in the pharynx, proximal esophagus, and distal esophagus. RESULTS Between-group comparison showed no significant difference in the reflux parameters in the distal esophagus between the studied groups. A significantly higher percentage of distal reflux episodes reached the proximal esophagus in the laryngitis group than in the control groups (P < 0.01), and the number of pharyngeal reflux episodes and time of acid exposure were significantly higher in the laryngitis group than in the control groups (P < 0.001). CONCLUSIONS Compared with normal controls and patients with gastroesophageal reflux disease, pharyngeal reflux of gastric acid is significantly more prevalent and the ratio of proximal to distal esophageal acid reflux episodes is significantly increased in patients with posterior laryngitis. Simultaneous three-site ambulatory pharyngoesophageal pH monitoring may provide supporting evidence when the diagnosis of reflux-induced aerodigestive tract lesions is considered.
The American Journal of Gastroenterology | 2004
Osamu Kawamura; Muhammad Aslam; Tanya Rittmann; Candy Hofmann; Reza Shaker
OBJECTIVES:Frequency occurrence of nonacidic and nonliquid reflux events in the pharynx has not been systematically studied. The aim of the present study was to characterize the physical (liquid, gas, and mixed gas/liquid) and pH properties of the gastroesophagopharyngeal refluxate.METHODS:We performed a total of 31 24-h simultaneous ambulatory pharyngoesophageal impedance and pH recordings in 11 GERD patients, 10 patients with reflux-attributed laryngitis, and 10 healthy controls.RESULTS:On average, the total number of reflux events (all kinds) in the pharynx was less than half of that in the proximal esophagus (18 ± 4 vs 50 ± 4, p < 0.01). Most of the pharyngeal reflux events were gas events and were observed in all three studied groups. Prevalence of these gas reflux events ranged between 0 and 74. The number of gas reflux events accompanied by a minor pH drop in laryngitis patients (1 (0–36)) was significantly higher than those in GERD and controls (0 (0–2) and 0 (0–1), respectively, p < 0.05). There was no significant difference in the number of nonacidic gas reflux events among the three groups (GERD: 10 (2–57), laryngitis: 11.5 (0–51), controls: 10.5 (0–27)). Impedance recording identified a total number of 566 events in the pharynx. Of these, a total of 563 events were compatible with gas reflux events, 101 events were accompanied by minor drops in intrapharyngeal pH, whereas 460 events were not accompanied by any pharyngeal pH change.CONCLUSIONS:Concurrent impedance and pH recordings detect significantly more events qualifying as reflux in the pharynx than pH recordings alone. A substantial majority of these events are gaseous refluxes both with and without minor pH drops. Gas reflux events with weak acidity appear to be more common among patients with reflux-attributed laryngeal lesions compared to GERD patients and controls.
Laryngoscope | 1998
Joan C. Kuhn; Robert J. Toohill; Seckin O. Ulualp; Judith I. Kulpa; Candy Hofmann; Ronald C. Arndorfer; Reza Shaker
Objective: Gastroesophageal reflux has been implicated in the pathogenesis of vocal cord nodules. However, a cause‐and‐effect relationship has not been established. Because documentation of pharyngeal acid reflux events makes this correlation more plausible, the aim of the present study was to determine the frequency of pharyngeal acid reflux events in patients with vocal cord nodules. Methods: Eleven patients with vocal cord nodules (mean age, 42 ± 6 years) and eleven healthy volunteers (mean age, 45 ± 6 years) were studied. Patients underwent barium esophagram and ambulatory 24‐hour simultaneous three‐site pharyngo‐esophageal pH monitoring. Controls only had ambulatory 24‐hour simultaneous three‐site pH monitoring. In the ambulatory pH monitoring studies, pH was recorded from the manometrically determined sites of pharynx (2 cm above upper esophageal sphincter), proximal esophagus (10 cm distal to pharyngeal site), and distal esophagus (5 cm above the lower esophageal sphincter). Pharyngeal acid reflux event was deemed acceptable if all three sites recorded a decrease in pH below 4 which was not related to meal or drinking. Results: Pharyngeal acid reflux events occurred in seven of 11 patients with vocal cord nodules (1–4 episodes) and two of 11 controls (1–2 episodes) (P < .05). In both groups all pharyngeal acid reflux events occurred in upright position and were not associated with belching or coughing. Barium studies documented hiatal hernia in two patients and gastroesophageal reflux in five of 11 patients. However, none of the esophageal reflux events reached the pharynx on barium esophagram. Conclusions: Prevalence of pharyngeal acid reflux events is significantly higher in patients with vocal cord nodules compared with normal controls and suggests a contributory role for gastroesophagopharyngeal acid reflux in the pathogenesis of some vocal cord nodules.
Neurogastroenterology and Motility | 2005
Sudarshan R. Jadcherla; Hao Q. Duong; Candy Hofmann; Raymond G. Hoffmann; Reza Shaker
Abstract We evaluated the upper oesophageal sphincter (UOS) relationship with oesophageal body during primary peristalsis (PP) sequences in healthy human neonates during maturation and compared with that of healthy adult volunteers. Forty‐nine studies were performed using a water perfusion manometry system and a specially designed oesophageal catheter with a UOS sleeve concurrent with submental electromyogram in 31 subjects in supine position (18 preterm neonates, 29.9 ± 2.5 weeks gestation; four full‐term neonates, 39.3 ± 1.0 weeks gestation; and nine adults, 18–65 years). The preterm neonates were studied longitudinally at 33 and 36 weeks postmenstrual age (PMA) and full‐term born at 40 weeks PMA. Data were compared between the groups to recognize the effects of gestation, postnatal age and ageing. We evaluated 403 consecutive spontaneous solitary swallows during maturation (preterm at time‐1 vs time‐2) and growth (preterm and full‐term vs adults) and observed significant (P < 0.05) differences in the basal UOS resting pressure, UOS relaxation characteristics, proximal and distal oesophageal body amplitude, duration, propagation and peristaltic velocity. Characteristics of UOS and PP are well‐developed by 33 weeks PMA and undergo further maturation during the postnatal period, and are significantly different from that of adult.
Annals of Otology, Rhinology, and Laryngology | 1999
Mark Kern; Candy Hofmann; Eytan Bardan; Junlong Ren; Ronald C. Arndorfer; Reza Shaker
Deglutitive upper esophageal sphincter opening (UES) in the elderly has been incompletely studied. Our aim was to determine in the elderly the temporal and dimensional characteristics of deglutitive UES opening; anterior and superior hyoid and laryngeal excursions as measures of distracting forces imparted on the UES; and hypopharyngeal intrabolus pressure (IBP). Fourteen healthy elderly and 14 healthy young volunteers were studied by concurrent videofluoroscopy and hypopharyngeal manometry during swallowing of 5- and 10-mL barium boluses. The anteroposterior UES diameter, as well as the anterior hyoid bone and laryngeal excursion, was significantly smaller in the elderly compared to the young (p < .05) for 5-mL barium boluses, but not for 10-mL boluses. The lateral diameter of UES opening was similar between groups for all boluses. The IBP for 5- and 10-mL swallows in the elderly was significantly higher than that in the young (p < .05). We conclude that anteroposterior deglutitive UES opening and hyoid bone and thyroid cartilage anterior excursion are reduced in the elderly. These changes are associated with increased IBP, suggesting a higher pharyngeal outflow resistance in the elderly compared to the young.
American Journal of Physiology-gastrointestinal and Liver Physiology | 2008
Adeyemi Lawal; Mark Kern; Arthi Sanjeevi; Stephen J. Antonik; Rachel Mepani; Tanya Rittmann; Syed Q. Hussaini; Candy Hofmann; Linda Tatro; Andrzej Jesmanowicz; Matthew Verber; Reza Shaker
The cingulate and insular cortices are parts of the limbic system that process and modulate gastrointestinal sensory signals. We hypothesized that sensitization of these two limbic area may operate in esophageal sensitization. Thus the objective of the study was to elucidate the neurocognitive processing in the cingulate and insular cortices to mechanical stimulation of the proximal esophagus following infusion of acid or phosphate buffer solution (PBS) into the esophagus. Twenty-six studies (14 to acid and 12 to PBS infusion) were performed in 20 healthy subjects (18-35 yr) using high-resolution (2.5 x 2.5 x 2.5 mm(3) voxel size) functional MRI (fMRI). Paradigm-driven, 2-min fMRI scans were performed during randomly timed 15-s intervals of proximal esophageal barostatically controlled distentions and rest, before and after 30-min of distal esophageal acid or PBS perfusion (0.1 N HCl or 0.1 M PBS at 1 ml/min). Following distal esophageal acid infusion, at subliminal and liminal levels of proximal esophageal distentions, the number of activated voxels in both cingulate and insular cortices showed a significant increase compared with before acid infusion (P < 0.05). No statistically significant change in cortical activity was noted following PBS infusion. We conclude that 1) acid stimulation of the esophagus results in sensitization of the cingulate and insular cortices to subliminal and liminal nonpainful mechanical stimulations, and 2) these findings can have ramifications with regard to the mechanisms of some esophageal symptoms attributed to reflux disease.
The American Journal of Gastroenterology | 2009
Kulwinder S. Dua; Sri Naveen Surapaneni; Rajesh Santharam; David Knuff; Candy Hofmann; Reza Shaker
OBJECTIVES:Injection of water into the pharynx induces contraction of the upper esophageal sphincter (UES), triggers the pharyngo-UES contractile reflex (PUCR), and at a higher volume, triggers an irrepressible swallow, the reflexive pharyngeal swallow (RPS). These aerodigestive reflexes have been proposed to reduce the risks of aspiration. Alcohol ingestion can predispose to aspiration and previous studies have shown that cigarette smoking can adversely affect these reflexes. It is not known whether this is a local effect of smoking on the pharynx or a systemic effect of nicotine. The aim of this study was to elucidate the effect of systemic alcohol and nicotine on PUCR and RPS.METHODS:Ten healthy non-smoking subjects (8 men, 2 women; mean age: 32±3 s.d. years) and 10 healthy chronic smokers (7 men, 3 women; 34±8 years) with no history of alcohol abuse were studied. Using previously described techniques, the above reflexes were elicited by rapid and slow water injections into the pharynx, before and after an intravenous injection of 5% alcohol (breath alcohol level of 0.1%), before and after smoking, and before and after a nicotine patch was applied. Blood nicotine levels were measured.RESULTS:During rapid and slow water injections, alcohol significantly increased the threshold volume (ml) to trigger PUCR and RPS (rapid: PUCR: baseline 0.2±0.05, alcohol 0.4±0.09; P=0.022; RPS: baseline 0.5±0.17, alcohol 0.8±0.19; P=0.01, slow: PUCR: baseline 0.2±0.03, alcohol 0.4±0.08; P=0.012; RPS: baseline 3.0±0.3, alcohol 4.6±0.5; P=0.028). During rapid water injections, acute smoking increased the threshold volume to trigger PUCR and RPS (PUCR: baseline 0.4±0.06, smoking 0.67±0.09; P=0.03; RPS: baseline 0.7±0.03, smoking 1.1±0.1; P=0.001). No similar increases were noted after a nicotine patch was applied.CONCLUSIONS:Acute systemic alcohol exposure inhibits the elicitation PUCR and RPS. Unlike cigarette smoking, systemic nicotine does not alter the elicitation of these reflexes.
Journal of Gastrointestinal Surgery | 2005
Dennis Blom; Shailesh Bajaj; Jianxiang Liu; Candy Hofmann; Tanya Rittmann; Thomas Derksen; Reza Shaker
Laparoscopic Nissen fundoplication (LNF) is the surgical treatment of choice for gastroesophageal reflux disease (GERD). Post-LNF complications, such as gas bloat syndrome, inability to belch and vomit, and dysphagia, remain too common and prevent LNF from being more highly recommended. It remains controversial as to whether preoperative assessment can predict the development of post-LNF complications. Some authors have shown a correlation between pre-LNF manometry characteristics and post-LNF dysphagia, and others have not. We hypothesize that many post-LNF complications are caused by a decrease in the distensibility of the GEJ and that standard manometry is at best an indirect measure of this. The aim of this study is to directly measure the effect of LNF on gastroesophageal junction (GEJ) distensibility (GEJD).The lower esophageal sphincter (LES) of 15 patients undergoing LNF was characterized using standard manometry. The GEJD before and after a standardized LNF was measured using a specialized catheter, containing an infinitely compliant bag, placed within the LES. GEJD was measured, as dV/dP over volumes 5 to 25 mL distended at a rate of 20 mL/min. Mean dP ± standard error of the mean for each volume was calculated, and distensibility curves were generated and compared. Measurements were also taken after abolishing LES tone by mid-esophageal balloon distension. Patient symptoms were recorded before and after surgery. Statistical analysis was performed by two-way repeated-measures analysis of variance, paired t test, and the Tukey test. Laparoscopic Nissen fundoplication led to a statistically significant increase in Dpressure over each volume tested and therefore a significant decrease in the distensibility of the GEJ. Abolition of LES tone had no statistical effect on GEJD after fundoplication. There were no complications, and none of the patients developed the symptom of dysphagia postoperatively. These are the first direct measurements to show that LNF significantly reduces the distensibility of the GEJ. We hypothesize that the magnitude of this reduction may be the vital variable in the development of post-LNF complications and specifically post-LNF dysphagia. The intraoperative measurement of LES distensibility may provide a means for avoiding this feared and other post-LNF complications in the future.
The American Journal of Gastroenterology | 2007
Muhammad Aslam; Shailesh Bajaj; Caryn Easterling; Osamu Kawamura; Tanya Rittmann; Candy Hofmann; Jianxiang Liu; Reza Shaker
BACKGROUND AND AIMS:Detection rate, influence of recording site, and subject posture for impedance monitoring of pharyngeal reflux of gastric contents remain unknown. We evaluated the ability of the impedance sensor for detection of various volumes of intrapharyngeal infusate at two sites and in two subject positions.METHODS:Nineteen healthy subjects were studied using concurrent videoendoscopic, manometric, impedance, and pH recording.RESULTS:Detection rate of simulated pharyngeal reflux events ranged between 87% and 100% for 1–4 mL. Detection rate for 0.1–1 mL volumes in the upright position was significantly higher (78–85%) when the impedance sensor was located at the proximal margin of the upper esophageal sphincter (UES) compared to 2 cm proximally (38–68%) (P < 0.001). With the sensor at 2 cm above the UES, the average detection rate for all volumes in the upright position was significantly less (P < 0.001) compared to the supine position (48% vs 84%). There was substantial variability in the magnitude of impedance changes induced by different infusates.CONCLUSIONS:Impedance sensors can detect as small a volume as 0.1 mL and combined with a pH sensor can detect acidic and nonacidic liquid and mist reflux events. Sensor placement at the proximal margin of the UES yields the highest detection rate irrespective of subject posture compared to placement 2 cm proximally. Depending on the volume of refluxate and location of the impedance sensor, a substantial minority of simulated reflux events can be missed.
Gastroenterology | 1992
Reza Shaker; Judith I. Kupla; Thomas M. Kidder; Ronald C. Arndorfer; Candy Hofmann
The manometric findings of deglutitive pharyngoesophageal function in a patient with the Kearns-Sayre syndrome and cervical dysphagia are described. These findings indicate that striated muscles of the pharynx, upper esophageal sphincter (UES), and proximal esophagus are involved. Near absence of pharyngeal peristalsis, abnormally low UES resting pressure, and absence of proximal esophageal peristalsis characterize the manometric findings in this patient. It is conceivable that in mild cases, a combination of various degrees of severity of the above findings may exist.