title: Upper punctal occlusion versus lower punctal occlusion in dry eye.
abstract: OBJECTIVE
  To compare the effectiveness of upper punctal occlusion versus that of lower punctal occlusion in dry eye patients.
  
  
  METHODS
  One eye's upper punctum and the contralateral eye's lower punctum were occluded with collagen plugs in 20 dry eye patients. The same procedure was performed in 20 normal subjects. The upper and lower tear menisci were imaged simultaneously by real-time OCT before punctal occlusion and repeated on days 1, 4, 7, and 10 afterward. The subjective symptom score, corneal fluorescein staining intensity, Schirmer I test result, and tear breakup time (TBUT) were also determined.
  
  
  RESULTS
  In dry eye patients, occlusion of either punctum improved symptom scores, fluorescein staining scores, TBUT, and lower tear meniscus height (LTMH, P < 0.05); however, Schirmer test scores and upper tear meniscus height (UTMH) did not change after occlusion (P > 0.05). There was no significant difference for any of these variables between upper punctum- and lower punctum-occluded eyes, before or after occlusion (P > 0.05). In normal subjects, Schirmer test scores, TBUT, UTMH, and LTMH did not change over time (P > 0.05).
  
  
  CONCLUSIONS
  Punctal occlusion with collagen plugs in dry eye patients leads to the relief of subjective symptoms and the improvement of objective signs. The effectiveness of occluding the upper or lower punctum is similar. The LTMH is a valid indicator of the success of punctal occlusion.
authors.affiliation: School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.forename: Jianhua
authors.initials: J
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Meixiao
authors.initials: M
authors.lastname: Shen
authors.forename: Suzhong
authors.initials: S
authors.lastname: Xu
authors.forename: Fan
authors.initials: F
authors.lastname: Lu
mesh_terms: D003094:Collagen; D003315:Cornea / Q000502:physiology; D015352:Dry Eye Syndromes / Q000503:physiopathology*; D005143:Eyelids / Q000503:physiopathology*; D005260:Female; D015590:Fluorophotometry; D006801:Humans; D007767:Lacrimal Duct Obstruction / Q000503:physiopathology*; D008297:Male; D011446:Prospective Studies; D019736:Prostheses and Implants; D011795:Surveys and Questionnaires; D013666:Tears / Q000737:chemistry*; D041623:Tomography, Optical Coherence; D055815:Young Adult
chemical_list: D003094:Collagen