Annamaria Staiano

Application of topographical methods to clinical esophageal manometry.

OBJECTIVE:Topographical manometric methods have improved the understanding of esophageal peristalsis in research applications but require a large number of recording sensors. Commonly used methods limited to four sensors were compared to topographical methods to determine whether the latter also had significant clinical utility.METHODS:Two hundred twelve patients referred for esophageal manometry were studied with a data acquisition system having 21 intraluminal recording sites, and the findings were analyzed independently using both limited (pull-through plus four recording sites) and topographical approaches (all sites). Discrepant results were clarified using supportive clinical data.RESULTS:The two methods were in diagnostic agreement in 187 cases (88.2%). Topographical methods correctly identified all 26 patients with achalasia within the group with aperistalsis (n = 36). The limited methods could not confidently identify six achalasia patients and were significantly less effective in segregating aperistaltic disorders (p < 0.05 across methods). Topographical methods alone detected evidence of incomplete lower esophageal sphincter relaxation in 12 additional patients, eight of whom had clinical data supporting the findings. Topographical methods identified the upper margin of the lower sphincter in all but three subjects (1.4%); limited methods could not identify this location in these and five additional subjects (3.8%) and differed from the topographical measurement by ≥2 cm in 11.9% of cases.CONCLUSIONS:Topographical methods are more accurate than commonly used methods in diagnosing the type of severe motor dysfunction and provide additional information important in the clinical practice of esophageal manometry.

Contraction abnormalities of the esophageal body in patients referred for manometry

A method is proposed for classifying conventional esophageal manometry findings according to the features observed in the esophageal body rather than by disease name. Patients who demonstrate increases in mean distal wave amplitude, mean distal wave duration, or number of abnormal motor responses (repetitive or simultaneous contractions) or the presence of triple-peaked waves are classified as having distal contraction abnormalities. Severity is scored by the cumulative number of these abnormalities. Of the 210 patients referred for esophageal manometry over a 23-month period, 119 (57%) were found to have one or more of the contraction abnormalities, making this the most common esophageal body manometric classification. The presence of one or two abnormalities was most common. Patients with all four abnormalities represented <5% of the referred population and, as a group, would satisfy usual manometric criteria for diffuse esophageal spasm. The proposed system allows for recognition of patients with only one or several of the manometric features typically seen in diffuse esophageal spasm and provides a method for intra- and interstudy comparison of patients with these common findings.

Manometric patterns using esophageal body and lower sphincter characteristics : findings in 1013 patients

In order to determine the actual spectrum of abnormal esophageal motility, manometric patterns in 1013 consecutive tracings were established using a classification method that employs esophageal body and lower esophageal sphincter (LES) characteristics. Peristaltic performance and contraction wave parameters were measured in the esophageal body; basal pressure and relaxation were included for the LES. Nine hundred thirty (92%) of the tracings could be completely classified, and 33 different patterns were observed (15 occurring at a rate >1%). Abnormalities were most common in contraction wave parameters (661 tracings, 65%), and least common in LES relaxation (105 tracings, 10%). Patterns most typical of achalasia and diffuse esophageal spasm were found in 6.4% and 5.0% of tracings, respectively. Statistical analysis of the patterns demonstrated that significant bidirectional predictive associations between categories were restricted to features representing pathology-based motor disorders (ie, achalasia and “sclerodermaesophagus”). This systematic classification method is capable of recognizing and cataloging common findings of motor dysfunction in the esophageal body and LES as well as uncommon patterns representing traditional motility disorders. Our findings provide reference data for clinical esophageal manometry.

Topographic analysis of esophageal double-peaked waves

BACKGROUND & AIMS Esophageal double-peaked waves occur with increased frequency in patients with functional esophageal symptoms. This study was undertaken to further understand the mechanisms responsible for their production. METHODS Topographic methods that consider temporal and spatial relationships of pressure data were used to examine 74 double-peaked waves detected in 18 subjects referred for manometric evaluation of unexplained symptoms. The studies were performed with a computerized data acquisition and analysis system designed for topographic plotting. RESULTS The second peak appeared to represent muscle contraction that merged with an unusually strong pressure site in the third topographic segment and covered 6.3 +/- 1.6 cm (33.5% +/- 8.5% esophageal length) proximal to this site. In 50 swallows (67.6%), the peak itself progressed in a retrograde direction at 13.2 +/- 10.8 cm/s, suggesting cephalad extension of a strong distal motor event. Analysis of wave onsets and movement of the peristaltic trailing edge detected retrograde propagation in up to 33.8% of waves, antegrade propagation in 2.7%, and simultaneous contraction in the remainder. CONCLUSIONS In symptomatic patients, the second peak in a double-peaked wave is typically a short, simultaneous, or retrograde pressure event in the region of and merging with the third topographic segment in the distal esophageal body. Topographic methods help explain the common association of these waveforms with other features of exaggerated contraction in the distal esophagus and suggest their relationship to inadequate inhibitory nerve function.

Letters to the EditorDouble Heterozygosity for a RET Substitution Interfering with Splicing and an EDNRB Missense Mutation in Hirschsprung Disease

The financial support of Telethon–Italy (grant E791) is gratefully acknowledged. This work was also funded by the Italian Telethon Foundation, the Italian Ministry of Health, and the European Community (contract MH4-CT97-2107).

Detection of incomplete lower esophageal sphincter relaxation with conventional point-pressure sensors

OBJECTIVE:Completeness of lower esophageal sphincter relaxation, a parameter used to establish the diagnosis of achalasia, is an important manometric determination. This study compared four analysis methods that use point-pressure measurements to determine their relative accuracy and the best threshold values for incomplete relaxation.METHODS:Analyses were performed on 153 manometric studies that employed a 21-lumen catheter with pressure recording sites spaced at 1-cm intervals. Lower sphincter relaxation was measured from most appropriate sites as the 1) lowest residual pressure within 5 s of swallowing, 2) lowest residual pressure across the entire postdeglutitive period, 3) lowest mean residual pressure over a floating 3-s interval after swallowing, and 4) mean transsphincteric esophagogastric gradient extracted from a combination of conventional and topographic manometric information. Intragastric baseline pressures were taken both from the pull-through maneuver and from concurrent intragastric recordings, and methods were compared by their receiver operating characteristics.RESULTS:Best threshold values for segregating achalasia from nonachalasic controls differed across methods and depended on presence or absence of peristalsis in the comparison group. Transsphincteric gradient measurement had high sensitivity (≥0.94) and specificity (≥0.98) for achalasia irrespective of comparison group and was superior to all other methods. The 3-s mean residual pressure demonstrated greatest discriminant capabilities of the remaining conventional methods, which were modestly improved with concurrent measurement of intragastric pressure.CONCLUSIONS:Analyses that average postdeglutitive pressures are superior to isolated nadir values in correctly discerning incomplete lower sphincter relaxation. The transsphincteric gradient is a novel approach for measuring sphincter relaxation, is unaffected by sphincter asymmetry and axial movement, and has the best receiver operating characteristics using point-pressure sensors.

Persistence of abnormal gastrointestinal motility after operation for Hirschsprung's disease

OBJECTIVE:Recent studies in patients with Hirschsprungs disease (HD) suggest that morphological abnormalities of the intramural intestinal plexuses are not restricted to the colon. In this report, symptoms and objective tests of gastrointestinal (GI) motor dysfunction were determined long after operative treatment to see whether evidence of a more widespread and relevant motility disturbance could be detected.METHODS:Twenty-one children were available for study an average of 6.6 yr after surgery for HD. All of these patients underwent evaluation of bowel frequency per week, total GI transit time (TGTT), and a scintigraphic gastric emptying test using solid food; anorectal manometry and segmental colonic transit times were performed in a subset of patients. Results were compared with findings in appropriately matched controls.RESULTS:Frequency of defecation per week in patients with HD after surgery was not different from that in control children, but TGTT was significantly longer (p < 0.01). Percentage retention of gastric isotope at 60 min exceeded the normal range in 12 of 21 (57.1%) patients, and colonic transit was abnormal in all six children studied. Symptoms persisted in two-thirds of patients postoperatively, and transit abnormalities were more common in the symptomatic subset (p = 0.026).CONCLUSIONS:Our data show that, in a subset of patients with HD, GI motor dysfunction persists long after surgical correction. The heterogeny of basic defects responsible for HD could provide the substrate for these motor abnormalities that, in turn, seem at least partially responsible for continuation of the symptomatic state.

Reevaluation of manometric criteria for vigorous achalasia. Is this a distinct clinical disorder

Clinical and manometric data from 97 consecutive patients with idiopathic achalasia were analyzed to see if a distinct subset with vigorous achalasia could be identified. Statistical analyses failed to detect a unique group of subjects based on the distribution of contraction wave amplitudes alone. Because of this, patients falling above the 95th percentile (N=4, mean wave amplitude>100 mm Hg for each) were compared with those having mean amplitudes above the conventional threshold for the diagnosis of vigorous achalasia (mean amplitude 60–100 mm Hg,N=4), and with the remainder (N=89, mean amplitude <60 mm Hg). Subjects with mean amplitudes <60 mm Hg and with mean amplitudes 60–100 mm Hg closely resembled each other in all measured clinical features, whereas subjects with mean amplitudes >100 mm Hg were all male, were older (67±4 years vs 47±2 years; P<0.01), and appeared to have somewhat longer duration of symptoms when compared with the remainder (82±41 vs 44±10 months;P=0.4). Chest pain and other esophageal symptoms, basal and residual lower sphincter pressures, and response to first treatment did not differ among the three groups. These data indicate that high-fidelity manometry techniques identify a rare subset of achalasia patients with mean contraction amplitudes exceeding 100 mm Hg that, although older and possibly with greater duration of symptoms, presents similarly to others with idiopathic achalasia. Outcome from conventional treatment is also similar for the “vigorous” and “nonvigorous” patients, making the distinction of questionable value.

Characteristics of the propagating pressure wave in the esophagus

Understanding the relationships of intraluminal manometric events to bolus transit through the esophagus has been limited by conventional manometric analysis methods. We reconstructed pressure events in the axial direction in order (1) to describe the peristaltic pressure wave as it propagates through the esophagus in the direction of the bolus and (2) to determine what sampling interval along the esophageal length is required for accurate representation. Esophageal manometric studies using the stepwise withdrawal method were performed in 10 asymptomatic volunteers. Propagating wave forms were created at 0.2-sec intervals and analyzed in static and dynamic fashion from averaged waves at each 1–3 cm of esophageal length. A distinctive and similar appearance to the propagating wave form, comprised of three sequential but overlapping contraction segments in the esophageal body, was present in nine subjects. The propagating wave decelerated as it approached the second region (smooth-muscle esophagus) and extended over as much as 15.1 ± 0.7 cm of esophageal length. No significant differences in wave front propagation, length, or velocity could be determined if the sampling interval increased from 1 to 3 cm of esophageal length, but peak amplitudes were reduced by as much as 14.2%. We conclude that the esophageal pressure wave, when viewed in the direction of bolus transit, is broad and typically comprised of three sequential contraction components. Sampling at >1-cm intervals along the esophageal length significantly alters the wave appearance and may be unsatisfactory in the distal esophagus. Axial transformations of manometric data potentially will provide better information concerning the neuromuscular control of peristalsis and events responsible for bolus movement.

Hiatus hernia and esophageal contraction abnormalities

The relationship of hiatus hernia to esophageal motility pattern was examined in patients referred for evaluation of esophageal symptoms. Results from standard esophageal motility studies were compared with findings on barium radiography of the upper gastrointestinal tract. Of 169 patients without radiographic evidence of esophagitis, 53 (31 percent) had normal motility of the esophageal body, whereas 116 (69 percent) demonstrated esophageal contraction abnormalities, a classification that includes the pattern of diffuse esophageal spasm at the severest extreme. Hiatus hernia was significantly more common in those with contraction abnormalities (25 percent) than in those with normal patterns (8 percent) (p = 0.01). Hiatus hernia increased in prevalence with increasing severity of contraction abnormalities, such that hiatus hernia was present in nearly half of patients with the pattern typifying diffuse esophageal spasm. Thus, hiatus hernia and esophageal contraction abnormalities are associated once other associations with hiatus hernia (e.g., esophagitis and scleroderma) have been excluded. These findings may help explain the recognized relationship of esophageal symptoms to hiatus hernia in patients without significant gastroesophageal reflux.