Objective    To evaluate tear film changes and recovery after closed vitrectomy.     Methods    Forty-two consecutive patients undergoing vitrectomy (42 eyes) were involved in this prospective randomized study. Uncomfortable symptoms were inquired

as well as tear break-up time (BUT)

Schirmer I test (SIt) value and corneal fluorescein staining (CSF) were measured on preoperative day 1 and postoperative day 1

3

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14 as well as in 1 month and 3 months postoperatively.      Results    On postoperative day 1

the dry eye symptoms scores and CFS scores increased significantly (P0.01)

and the stable tear film failed to form. However

the SIt value of 35 patients exceeded 30 mm

while that of the rest 7 patients exceeded 25 mm. On postoperative day 3

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the dry eye symptoms scores increased significantly (P0.01

P0.05)

and returned to their preoperative values on day 14 (P0.05). On postoperative day 3

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the mean BUT decreased significantly (P0.01)

the mean SIt value and CFS scores increased significantly (P0.01). At 1 month after operation

the mean BUT was still significantly lower than that before operation (P0.05)

while the mean SIt value and CFS scores returned to their preoperative values (P0.05). At 3 months after operation

the mean BUT returned to the level before operation (P0.05).      Conclusion    Vitrectomy significantly alters the stability of tear film. The tear film function returned to preoperative conditions in 3 months after operation.