High-resolution Pressure Topography Research Articles

Factors Determining the Inter-observer Variability and Diagnostic Accuracy of High-resolution Manometry for Esophageal Motility Disorders.

Background/AimsAlthough high-resolution manometry (HRM) has the advantage of visual intuitiveness, its diagnostic validity remains under debate. The aim of this study was to evaluate the diagnostic accuracy of HRM for esophageal motility disorders.MethodsSix staff members and 8 trainees were recruited for the study. In total, 40 patients enrolled in manometry studies at 3 institutes were selected. Captured images of 10 representative swallows and a single swallow in analyzing mode in both high-resolution pressure topography (HRPT) and conventional line tracing formats were provided with calculated metrics.ResultsAssessments of esophageal motility disorders showed fair agreement for HRPT and moderate agreement for conventional line tracing (κ = 0.40 and 0.58, respectively). With the HRPT format, the κ value was higher in category A (esophagogastric junction [EGJ] relaxation abnormality) than in categories B (major body peristalsis abnormalities with intact EGJ relaxation) and C (minor body peristalsis abnormalities or normal body peristalsis with intact EGJ relaxation). The overall exact diagnostic accuracy for the HRPT format was 58.8% and rater’s position was an independent factor for exact diagnostic accuracy. The diagnostic accuracy for major disorders was 63.4% with the HRPT format. The frequency of major discrepancies was higher for category B disorders than for category A disorders (38.4% vs 15.4%; P < 0.001).ConclusionsThe interpreter’s experience significantly affected the exact diagnostic accuracy of HRM for esophageal motility disorders. The diagnostic accuracy for major disorders was higher for achalasia than distal esophageal spasm and jackhammer esophagus.

Comparison of High Resolution Pressure Topography and High Resolution Impedance Manometry in Patients With Non-obstructive Dysphagia

Introduction: High resolution pressure topography (HRPT) facilitates better characterization of esophageal peristalsis than conventional waveforms (CW), including recognition of ineffective esophageal motility (IEM). Likewise, high resolution impedance manometry (HRIM) provides information regarding bolus transit. It is not known if HRIM confers a diagnostic advantage over HRPT in the assessment of peristalsis in patients with non-obstructive dysphagia (NOD). Methods: Patients with NOD were evaluated with a 36-pressure and 18-impedance solid-state esophageal probe. Failed, weak and normal peristalses were identified with HRPT, HRIM and CW, independently by two assessors. Abnormal and normal peristalses were compared between the techniques. ROC curve analysis was used to determine area under the curve (AUC), sensitivity and specificity for a diagnosis of IEM using HRIM at cut-offs of 50% (HRIM50%) and 30% (HRIM30%) with CW50% and HRPT50% as references. Results: 81/111 screened patients (F/M = 57/24; mean age 53 years) were evaluated. With HRPT, IEM was seen in 28.0±3.6 % of water swallows, of which failed peristalses were seen in 11.0±2.7 % and weak peristalses in 17.0 ± 2.4 %. Of those ineffective swallows, 8.8±1.8 % were large breaks, 10.5±1.1% were small breaks and 35.4±4.0 % had transition zone defects (TZDs) (mean length 3.1±0.3 cm). Less than a third of subjects had a mean distal contractile integral (DCI)<450 mmHg-s-cm. With HRIM, IEM was seen in 35.1±4.0 %, of which 17.2 ± 3.1 % were failed peristalses and 17.9 ± 2.7% were weak peristalses. The mean distal baseline impedance was 1.3±0.1Ω. TZDs with impaired bolus clearance were seen in 19.4±3.2%. Comparing HRIM vs. HRPT, more failed peristalses (1.8±0.3 vs. 1.2±0.3, P=0.02) were identified, but weak peristalses (1.8±0.3 vs. 1.8±0.3, P=1.0) and normal peristalses (6.1±0.4 vs. 6.0±0.4,P =0.8) were similar. Using ROC curve analysis, the % of AUCs, sensitivities and specificities for HRIM50% (63.2, 48.4 and 78.0 respectively) and HRPT50% (68.2, 48.4 and 88.0 respectively) were both better than CW50% (both P<0.05). Compared with HRPT50%, the % of AUCs, sensitivities and specificities were equally better with HRIM30% (69.8, 76.2 and 63.3 respectively, P=0.007) and HRIM50% (73.3, 66.7 and 80.0 respectively, P=0.002). Conclusion: HRIM is more likely to identify peristaltic defects than HRPT, and therefore is a better test for the assessment of NOD. To diagnose IEM, HRIM30% and HRIM50% were both equally better than HRPT50% and CW50%, and should be the preferred approach. Disclosure - Dr. Rao is supported by a grant from National Institutes of Health NIH grant RO1 DK 57100-05NIHRO-1.

Mo2008 Anorectal Manometry in Dyssynergic Defecation: Comparative Analysis of High-Resolution Pressure Topography and Waveform Manometry

quality (5/8 (63%) nulliparous vs. 3/13 (23%) parous) having recordings of excellent quality. Conclusions Electrical stimulation of the anal canal at motor threshold and recording of AEPs from channel Cz'-Fz is a reliable and reproducible method for examination of anal sensory function. Recordings of excellent quality are recorded from most healthy volunteers. Inability to record AEPs in patients with FI may suggest underlying injury to central sensory pathways.