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Updated: Aug 25, 2026

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring
Published on: December 9, 2010
Localization of local anesthetic solution by magnetic resonance imaging
Leila Niemi-Murola1, Kari Krootila, Riku Kivisaari
1Department of Anesthesiology, Eye and ENT Hospital, Helsinki University Central Hospital, Helsinki, Finland.
Purpose:
The aim of this study was to examine the distribution of local anesthetic solution by magnetic resonance imaging (MRI) after combined peribulbar and retrobulbar, superomedial retrobulbar, and sub-Tenon's injection in relation to clinical akinesia.
Design:
Randomized clinical trial.
Participants:
Fifteen patients scheduled for cataract surgery, 5 patients in each group.
Methods:
Five patients received combined peribulbar and retrobulbar anesthesia, 5 patients received superomedial retrobulbar injection, and 5 patients had sub-Tenon's injection, all with a combination of bupivacaine 0.75%, lidocaine 2%, and hyaluronidase. The MRI scans were performed before the injection and up to 35 minutes after the injection.
Results And Conclusions:
Reliable anesthesia is achieved using a combined peribulbar and retrobulbar block and a relatively great volume of local anesthetic solution, which spreads throughout the orbit, as evidenced by MRI. After superomedial retrobulbar and sub-Tenon's injection, the local anesthetic solution accumulates behind the globe. Sub-Tenon's injection gives good analgesia and slight akinesia with a very small volume. Superomedial retrobulbar injection and combined peribulbar and retrobulbar block provide a similar degree of exophthalmos, which seems to be the result of the volume injected behind the globe.
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