Bupivacaine injection of eye muscles to treat strabismus.
BACKGROUND
Bupivacaine injected into animal muscles induces a cycle of myotoxicity, degeneration, regeneration and hypertrophy of muscle fibres, without adverse effects on other tissues. This induced hypertrophy can be harnessed to treat strabismus.


METHODS
Bupivacaine, 4.5 ml of a 0.75% solution, was injected into the right lateral rectus (RLR) muscle of a patient who had diplopia and who showed 14-prism-dioptres oesotropia.


RESULTS
RLR paresis persisted for 7 days. Then, the RLR regained its abducting ability, and progressive improvement of alignment to 4-prism-dioptres oesophoria occurred over the next 33 days, with the elimination of diplopia. Alignment remained the same at 54 days after injection. Magnetic resonance imaging showed a focal increase in the size of the injected RLR of 58% in the posterior area, with reduced change in anterior portions of the RLR.


CONCLUSIONS
Injection of bupivacaine to induce hypertrophy of the injected muscle and thus alter eye alignment was effective in our patient. This approach can be a useful addition to the treatment of strabismus.
Scott
Alan B
AB
Smith-Kettlewell Eye Research Institute, 2318 Fillmore Street, San Francisco, CA 94115, USA. abs@ski.org
Alexander
Danielle E
DE
Miller
Joel M
JM
D000368:Aged; D000779:Anesthetics, Local / Q000627:therapeutic use*; D002045:Bupivacaine / Q000627:therapeutic use*; D004172:Diplopia / Q000209:etiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D009801:Oculomotor Muscles / Q000473:pathology; D009915:Orbit / Q000473:pathology; D013285:Strabismus / Q000150:complications / Q000188:drug therapy* / Q000473:pathology
D000779:Anesthetics, Local; D002045:Bupivacaine