CASE REPORT: A UNIQUE CASE OF BRAINSTEM ANESTHESIA AND CONTRALATERAL AMAUROSIS AFTER A SUBTENON BLOCK.

PURPOSE: To report and discuss a case of brainstem anesthesia and contralateral amaurosis after a sub-Tenon block.

METHODS

Single surgical case report of a patient who underwent an uncomplicated pars plana vitrectomy for an epiretinal membrane peel in the left eye after a sub-Tenon anesthesia technique.

RESULTS

Postoperatively, the patient experienced symptoms of brainstem anesthesia as well as akinesia, a nonreactive pupil, and reduced visual acuity in the contralateral eye that gradually resolved within 24 hours. Imaging was within normal limits and did not reveal any anatomic abnormalities.

CONCLUSION

Despite the use of a blunt-ended cannula in a sub-Tenon block, there is a non-negligible risk of it penetrating surrounding structures such as the optic nerve sheath. This case emphasizes the importance of monitoring for brainstem anesthesia and contralateral eye involvement in patients both intra- and postoperatively.