Symptom score questionnaire for nasolacrimal duct obstruction in adults--a novel tool to assess the outcome after endoscopic dacryocystorhinostomy

BACKGROUND: The incidence of nasolacrimal pathway obstruction increases with age, and dacryocystorhinostomy (DCR) is a commonly applied surgical technique to treat severe cases. However, no disease-specific tools to assess the symptoms and the subjective outcome after DCR have been established. We have developed a specific Nasolacrimal Duct Obstruction Symptom Score (NLDO-SS) questionnaire to evaluate the outcome, and tested it in a prospective clinical trial. STUDY DESIGN: Prospective clinical follow-up study. METHODS: Sixty-eight consecutive primary endoscopic dacryocystorhinostomy (EN-DCR) procedures were performed in 64 patients during 2004-2008. Preoperatively and during the three follow-up visits (at 1 week, 2 and 6 months), the patients filled in the NLDO-SS, and at the second and third follow-up visits they also filled in the Glasgow Benefit Inventory (GBI) questionnaire. At one year after the operation, a GBI questionnaire was sent to the patients. RESULTS: The surgical success rate of EN-DCR was 93 %. EN-DCR resulted in a significant reduction in all of the eight symptoms scores of the NLDO-SS (p= 0.001). The GBI scores indicated a significant benefit at 2 months (+37 (SD; 28) and an even higher benefit at 6 months after surgery (+52 (SD; 29), p= 0.001), but no further improvement was found between 6 and 12 months (+52 vs +52, p= 1.0). The correlation between the total GBI and NLDO-SS was significant (p=0.001). CONCLUSIONS: EN-DCR significantly improves the quality of life as measured by the GBI. The NLDO-SS correlated with the GBI and gave more information about the benefits after EN-DCR than GBI alone. The NLDO-SS proved to be an effective tool to evaluate lacrimal obstructions and EN-DCR benefits. Further studies to validate NLDO-SS are needed.