Comparative Evaluation of the Ostium After External and Nonendoscopic Endonasal Dacryocystorhinostomy Using Image Processing (Matlabs and Image J) Softwares.
OBJECTIVE
The purpose of this study was to compare the characteristics of the ostium after external dacryocystorhinostomy and nonendoscopic endonasal dacryocystorhinostomy (NEN-DCR).


METHODS
This cross-sectional study included patients who underwent a successful external dacryocystorhinostomy or NEN-DCR and had ≥1 month follow up. Pictures of the ostium were captured with a nasal endoscope (4 mm, 30°) after inserting a lacrimal probe premarked at 2 mm. Image analyses were performed using Image J and Contour softwares.


RESULTS
Of the 113 patients included, external dacryocystorhinostomy group had 53 patients and NEN-DCR group had 60 patients. The mean age of patients in the NEN-DCR group (38 years) was significantly (p < 0.05) lower than the external dacryocystorhinostomy group (50 years). There was no statistically significant difference (2 sample t test, p > 0.05) in mean follow up (6 vs. 4 months), maximum diameter of ostium (8 vs. 7 mm), perpendicular drawn to it (4 vs. 4 mm), area of ostium (43 vs. 36 mm), and the minimum distance between common internal punctum and edge of the ostium (1 vs. 1 mm) between the external and NEN-DCR groups.


CONCLUSIONS
Image processing softwares offer simple and objective method to measure the ostium. While ostia are comparable in size, their relative position differs with posteriorly placed ostia in external compared with inferior in NEN-DCR.
*Ophthalmic Plastic and Reconstructive Surgery Service, L. V. Prasad Eye Institute, Bhubaneswar, India; and †Departments of Clinical Epidemiology and Biostatistics, L. V. Prasad Eye Institute, Hyderabad, India.
Anasua
A
Ganguly
Hrishikesh
H
Kaza
Aditya
A
Kapoor
Jenil
J
Sheth
Mohammad Hasnat
MH
Ali
Devjyoti
D
Tripathy
Suryasnata
S
Rath
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003430:Cross-Sectional Studies; D003608:Dacryocystorhinostomy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007767:Lacrimal Duct Obstruction / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009301:Nasolacrimal Duct / Q000000981:diagnostic imaging* / Q000601:surgery; D009666:Nose; D011446:Prospective Studies; D012984:Software; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013997:Time Factors; D055815:Young Adult