Differential flow rate of commercially available triamcinolone with and without preservative through small-gauge needles

Mariana Cabrera, Alex Gonzalez, Thomas A. Albini, Cornelis Rowaan, Mariela Aguilar, William Lee, Jorge A. Fortun, Andrew A. Moshfeghi, Harry W. Flynn, Jean Marie A. Parel

Research output: Contribution to journalArticle

1 Scopus citations


OBJECTIVE: To compare the flow rate through different gauge needles of triamcinolone acetonide with benzyl alcohol (TABA) versus preservative-free triamcinolone acetonide injectable suspension (TAIS). MATERIALS AND METHODS: Experimental injections of 1 mL of TABA or TAIS were performed through a 27-, 30-, or 32-gauge needle. A piezoelectric pressure transducer connected to a personal computer was placed between the syringe and needle to record the force-time relationship and assess the flow rate (mL/s). Measurements were performed in triplicate. RESULTS: Flow rates were similar between preparations using a 27-gauge needle. Using a 30-gauge needle, the flow rate was 0.058 mL/s for TABA and 0.178 mL/s for TAIS. Using a 32-gauge needle, no flow was sustained by TABA, whereas the flow rate of TAIS was 0.114 mL/s (P < .05). CONCLUSION: TAIS can be injected through a 32-gauge needle without the risk of obstruction. Occlusions were seen with TABA using the 30- and 32-gauge needles.

Original languageEnglish (US)
Pages (from-to)54-57
Number of pages4
JournalOphthalmic Surgery Lasers and Imaging Retina
Issue number1
StatePublished - Jan 1 2014


ASJC Scopus subject areas

  • Surgery
  • Ophthalmology

Cite this