Determining fluid level in a translucent eye-drop bottle: transillumination by penlight

Int Ophthalmol. 1996;20(5):229-30. doi: 10.1007/BF00131916.


We describe an easy way to determine eye-drop contents in translucent bottles. Transillumination of eye-drop bottles from behind or the bottom by using a penlight clearly defines the fluid levels. The described procedure may prevent disposal of eye-drop bottles containing useful amounts of medication and prevent Ophthalmologists and Patients unexpectedly coming across an empty bottle.

MeSH terms

  • Disposable Equipment
  • Drug Packaging*
  • Humans
  • Light
  • Ophthalmic Solutions / analysis*
  • Ophthalmology / methods*
  • Transillumination / methods*


  • Ophthalmic Solutions