An interventional study of External Dacryocystorhinostomy and Powered Endoscopic Dacryocystorhinostomy in Primary Acquired Nasolacrimal Duct Obstruction, sponsored by Military Institute od Medicine National Research Institute. Completed at 1 site in Poland. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-10.
Sponsored by Military Institute od Medicine National Research Institute · Not applicable, Interventional, and Treatment
Primary acquired nasolacrimal duct obstruction causes persistent tearing because tears cannot drain normally from the eye into the nose. The purpose of this randomized study was to compare two operations used to restore tear drainage: external dacryocystorhinostomy, performed through a small skin incision near the inner corner of the eye, and powered endoscopic dacryocystorhinostomy, performed through the nose using an endoscope and powered instruments, with mitomycin C applied during surgery to reduce scar formation.
Participants were assigned to the two surgical groups using a pre-generated randomization list. Recruitment was completed after 60 participants had been enrolled, resulting in 30 participants in each group. Participants were followed for 12 months after surgery.
The main outcomes were whether the newly created tear drainage opening remained open and whether tearing symptoms improved. Additional assessments included postoperative symptom severity, patient satisfaction, surgical complications, cosmetic concerns related to the external scar, and willingness to undergo the same procedure again.
This was a prospective, randomized, single-center clinical study involving patients with primary acquired nasolacrimal duct obstruction. The study compared external dacryocystorhinostomy with powered endoscopic dacryocystorhinostomy performed with intraoperative application of mitomycin C.
Participants were assigned to the two surgical groups using a pre-generated randomization list. Recruitment was completed after 60 participants had been enrolled, resulting in 30 participants in the external dacryocystorhinostomy group and 30 participants in the powered endoscopic dacryocystorhinostomy group.
Participants were followed for 12 months after surgery. Anatomical success was defined as a patent rhinostomy opening confirmed by nasal endoscopic examination and lacrimal irrigation. Functional success was defined as a postoperative Munk score of 1 or lower. Overall surgical success required both anatomical and functional success.
Additional assessments included postoperative Munk score, complete resolution of tearing defined as a Munk score of 0, patient satisfaction, willingness to undergo the same procedure again, postoperative complications, and cosmetic concerns related to the external surgical scar.
36 studies on the registry are indexed under Lacrimal Apparatus Diseases; 2 are open to participants now.
This study's enrollment of 60 is above the median of 24 across 25 interventional studies indexed under Lacrimal Apparatus Diseases.
Browse Lacrimal Apparatus Diseases studies →Military Institute od Medicine National Research Institute is the lead sponsor of 45 studies on the registry; 6 are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants assigned to this arm underwent external dacryocystorhinostomy with intraoperative application of mitomycin C.
Procedure: External Dacryocystorhinostomy · Drug: Mitomycin C 0.02%
Participants assigned to this arm underwent powered endoscopic dacryocystorhinostomy with intraoperative application of mitomycin C.
Procedure: Powered Endoscopic Dacryocystorhinostomy · Drug: Mitomycin C 0.02%
External dacryocystorhinostomy was performed through a skin incision near the medial canthus. A bony ostium was created between the lacrimal sac and the nasal cavity, and the lacrimal and nasal mucosal flaps were opened and anastomosed to establish a new tear drainage pathway.
Powered endoscopic dacryocystorhinostomy was performed through the nasal cavity using an endoscope, a microdebrider, and a powered drill. The lacrimal sac was widely exposed and opened to create a new tear drainage pathway into the nasal cavity.
Mitomycin C at a concentration of 0.2 mg/mL was administered to the lateral nasal mucosa around the rhinostomy site. Sponges soaked with mitomycin C were applied to the edges of the newly created rhinostomy for 3 minutes during both external and powered endoscopic dacryocystorhinostomy.
Anatomical Patency of the Rhinostomy
Number of participants with a patent rhinostomy ostium confirmed by both nasal endoscopic examination and lacrimal irrigation.
Time frame: 12 months after surgery
Epiphora Severity Assessed by the Munk Score
Epiphora severity was assessed using the Munk score ranging from 0 to 5. A score of 0 indicated no tearing, and a score of 5 indicated constant tearing requiring continuous wiping. Lower scores indicated less severe epiphora.
Time frame: 12 months after surgery
Patient-Reported Perceived Surgical Effectiveness
Participant-reported perceived effectiveness of the surgical procedure assessed on a 5-point scale, ranging from 1, indicating very low effectiveness, to 5, indicating very high effectiveness. Higher scores indicated greater perceived effectiveness.
Time frame: 3 to 4 months after surgery
Patient-Reported Epiphora Burden
Participant-reported burden of epiphora assessed using a 5-point verbal rating scale ranging from 1 to 5. A score of 1 indicated no or minimal burden, and a score of 5 indicated maximum burden. Lower scores indicated less troublesome epiphora.
Time frame: 3 to 4 months after surgery
Fluorescein Dye Disappearance Test Score
Tear drainage was assessed using the fluorescein dye disappearance test on a scale from 0 to 4. Scores of 0 or 1 indicated normal or nearly normal tear drainage, whereas scores from 2 to 4 indicated increasing fluorescein retention and impaired tear drainage. Lower scores indicated better tear drainage.
Time frame: 3 to 4 months after surgery
Rhinostomy Ostium Width
Width of the rhinostomy ostium measured in millimeters during nasal endoscopic examination. Greater values indicated a wider postoperative rhinostomy opening.
Time frame: 12 months after surgery
Discomfort Associated With Crawford Tube Intubation
Number of participants who reported discomfort associated with the implanted Crawford silicone tube, assessed using a yes-or-no question.
Time frame: 3 to 4 months after surgery
Willingness to Undergo the Same Procedure Again
Number of participants who reported that they would be willing to undergo the same surgical procedure again if medically necessary, assessed using a yes-or-no question.
Time frame: 3 to 4 months after surgery
Cosmetic Concern Related to the External Surgical Scar
Number of participants in the external dacryocystorhinostomy group who considered the postoperative external surgical scar to be a cosmetic problem, assessed using a yes-or-no question.
Time frame: 3 to 4 months after surgery
Plan to share: No — Individual participant data will not be shared because the study consent and ethics documentation did not establish a formal mechanism for sharing de-identified individual-level data with external researchers.
Ran from Jul 2023 to primary completion in Mar 2026, 31 months.
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Military Institute od Medicine National Research Institute