The present invention relates to a fiber comprising a biodegradable polymer which undergoes dimensional change upon injection in the human or animal body wherein the dimensional change is a reduction of the surface area to volume ratio of a factor 2 to10. The fiber is sized for injection via a pharmaceutical syringe needle having a bore of at least 25 Gauge. The biodegradable polymer is an amorphous biodegradable polymer selected from the group of poly-hexamethylene carbonates or polyesteramides. The amorphous biodegradable polymer is a preferably a polyesteramide comprising alpha -amino acids, diols and dicarboxylic acids as building blocks. The invention further relates to the use of the fiber for the manufacturing of a medicament for the treatment of ophthalmic diseases. The invention also relates to a process for the manufacturing of the fiber comprising the following process steps a. extruding a biodegradable polymer into a fiber fitting in a needle of at least 25 Gauge b. which while under tension is cooled below its glass transition temperature such that the resultant fiber is amorphous.
