An observational study in CRS, sponsored by University of Alabama at Birmingham. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-22.
Sponsored by University of Alabama at Birmingham · Observational
The purpose of this study is to establish the novel endoscopically-directed sinus potential difference (EDSPD) assay as an endpoint for therapy of sinus disease.
The purpose of this study is to establish the novel endoscopically-directed sinus potential difference (EDSPD) assay as an endpoint for therapy of sinus disease. This assay provides a means to measure Cl- secretion across the sinus epithelium in human subjects with chronic rhinosinusitis (CRS) and test the relationship between this data and endoscopic findings of inflammation. The technique is appropriate for investigating acquired CFTR dysfunction in sinus epithelium and examining the therapeutic potential of CFTR potentiators for CRS.
University of Alabama at Birmingham is the lead sponsor of 1,397 studies on the registry; 285 are open to participants now.
Of its 156 completed or terminated interventional studies of FDA-regulated products, 124 (79%) have results posted.
Counted across the registry records on this site, refreshed daily.
Participants will be derived from those patients presenting to UAB for endoscopic evaluation of CRS, or who present for standard-of-care sinus or skull base surgery.
Patient eligibility criteria are designed to limit enrollment otherwise healthy individuals who are scheduled for standard-of-care nasal endoscopy in the clinic or sinus/skull base surgery.
Inclusion criteria:
Exclusion criteria:
Endoscopically-directed sinus potential difference (EDSPD) will be conducted in either the operating room or in the rhinology clinic setting to quantify CFTR activity in the sinus cavities. The potential difference will be monitored in actively inflamed areas as judged by endoscopy in comparison to an agar-filled reference butterfly electrode placed in the volar aspect of the forearm. A stable potential with the mean value of a 10-s scoring interval after perfusion of each solution will be recorded by a blinded investigator.
Other: EDSPD
Endoscopically-directed sinus potential difference (EDSPD) will be conducted in either the operating room or in the rhinology clinic setting to quantify CFTR activity in the sinus cavities. The potential difference will be monitored in actively inflamed areas as judged by endoscopy in comparison to an agar-filled reference butterfly electrode placed in the volar aspect of the forearm. A stable potential with the mean value of a 10-s scoring interval after perfusion of each solution will be recorded by a blinded investigator.
Other: EDSPD
The equipment \& conditions for measuring bioelectric changes across the sinus mucosa are based on the standard NPD protocol, including use of agar-filled PE90 tubing for the probing electrode and limiting perfusion solutions to Ringer, Ringer + amiloride (100 µM), chloride-free gluconate with amiloride + isoproterenol (10 µM). The potential difference will be monitored in actively inflamed areas as judged by endoscopy in comparison to an agar-filled reference butterfly electrode placed in the volar aspect of the forearm. A stable potential with the mean value of a 10-s scoring interval after perfusion of each solution will be recorded by a blinded investigator.
Ability to measure CFTR difference using EDSPD testing
To establish the relationship of EDSPD findings with other validated instruments and markers of CRS disease
Time frame: 3 Years
Plan to share: No
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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University of Alabama at Birmingham