How to remove tiny (invisible) pieces of metal from my laceration?

Foreign Body: Typically the smaller the fragments the more difficult they are to remove. If there is specific laceration then it can be opened, debrided under direct visualization using special glasses that magnify small objects. This is usually adequate. Use of a microscope can be needed but rarely is indicated.

May not be possible: With a laceration (open wound), proper care involves thorough cleansing, irrigation and sometimes debridement (removal of foreign debris and any devitalized tissue) depending on the situation. It is not always possible or practical to remove all foreign material (especially if tiny and "invisible"). An x-ray may be helpful to localize metal but sometimes it is best to leave it be and follow up.