Sir,

Thank you for your kind letter. I am willing to talk about our experience about the exuberant conjunctival overgrowth because of the tube implantation.

First, I would like to thank Dr R Redmond1 for his dissective study. According to our experience, conjunctival overgrowth was in faith the most common complication in the use of the Medpor-coated tear drainage tube and would cause tube obstruction. In our paper, we had discussed the problem. The reason for the exuberant conjunctival overgrowth is not very clear, and may be related to the porous polyethylene coat of the tube.

About the conjunctival overgrowth, for one thing, to reduce the granulation tissue overgrowth, we should tell the patients in detail how to care for the tube after operation. For another, the hypertrophic tissues can be excised and the stump cauterized to prevent the tissue regrowth. Then it is necessary to suture the conjunctiva around the tube.

If the recurrent conjunctival overgrowth actually happened time after time, removing the tube is the last choice. According to our experience, it is easy to remove the borosilicate glass tube. We first slit the Medpor sheath with a blade or scissors, then removed the glass tube with forceps. During the surgery it is necessary to avoid spalling the glass tube and to completely remove the Medpor sheath.