Satish SC. Rao, MD, PhD, FACG1, Karlo Fidel, MD1, Danielle Long, BS1, Delaram Asadi, MD1, Kamran Ayub, MD, MRCP2, Allan Weston, MD, FACG3 1Augusta University Medical Center, Augusta, GA; 2Southwest Gastroenterology, a Division of GI Partners of Illinois, Oak Lawn, IL; 3Digestive Health Center of the Four States, LLC, Joplin, MO Introduction: Anorectal manometry (ARM) is a core diagnostic tool for assessing anorectal function including coordination and sphincter integrity in patients with constipation and fecal incontinence. Catheter design significantly influences pressure measurements, and as such, catheter-specific normative data are critical for clinical interpretation. A novel 10-Channel Air-Charged Disposable High-Resolution Anorectal Manometry (HRAM) Catheter system (Solar™ catheter) was used to develop reference values for this system in healthy adults. Methods: ILLUMINATE was a prospective, multi-center, open-label study wherein each subject underwent standardized HRAM using the 10-channel, 12F air-charged disposable HRAM catheter following IAPWG and London Classification protocols. Outputs including anal resting pressure, squeeze pressure, cough pressure, and functional anal canal length were assessed. Descriptive statistics were used to generate normative datasets, stratified by gender. Results: We enrolled 81 healthy adults (21 males, 60 females; mean age = 41 ± 12 years) participated in the study. Mean anal resting pressure was 80.52 mmHg (SD ± 18.02) in males and 77.00 mmHg (SD ± 23.40) in females. Other normative parameters are shown in Table 1. No adverse events occurred. All procedures were completed without difficulty, and data collection was complete across all subjects. Discussion: In this prospective study we describe normative anorectal pressure values and rectal sensory thresholds in healthy subjects using a novel 10-Channel Air-Charged Disposable High-Resolution Anorectal Manometry (HRAM) Catheter. Some parameters, for example, maximum squeeze pressure and rectal sensory thresholds were different between genders, but most of the others were similar. These reference values could be useful when comparing data in patients with anorectal disorders and support the clinical application of air-charged disposable HRAM catheters, and it also reinforces the need for catheter-specific and gender-based data when interpreting ARM results.
Figure: Table 1. Normative Anorectal Function Parameters (Mean ± SD)
Figure: Table 2. Summary of key ARM metrics by demographic subgroups
Disclosures: Satish Rao: Laborie Medical Technologies – Grant/Research Support. Vibrant Ltd – Advisory Committee/Board Member. Karlo Fidel indicated no relevant financial relationships. Danielle Long indicated no relevant financial relationships. Delaram Asadi indicated no relevant financial relationships. Kamran Ayub: Laborie Medical Technologies – Grant/Research Support. Allan Weston: Laborie Medical Technologies – Grant/Research Support.
Satish SC. Rao, MD, PhD, FACG1, Karlo Fidel, MD1, Danielle Long, BS1, Delaram Asadi, MD1, Kamran Ayub, MD, MRCP2, Allan Weston, MD, FACG3. P2449 - Normative Datasets for Standard Measures of Anorectal Function With an Air Charged HRAM Catheter, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.
