Purpose: To review intraoperative choroidal detachments during 23-gauge vitrectomy and examine possible mechanism(s) involved.
Methods: A retrospective consecutive case review of 23-gauge vitrectomies was performed. Main outcomes included choroidal detachment incidence, location, extent, relation to infusion cannula, and postoperative course. Laboratory study of human donor eyes was conducted by placing 23-gauge cannulas at various angles through the pars plana and injecting viscoelastic material after cannula retraction.
Results: Among 338 consecutive 23-gauge vitrectomy cases, 12 (3.55%) intraoperative choroidal detachments occurred. These included 6 (1.77%) serous detachments, 4 (1.18%) limited hemorrhagic detachments, and 1 case each of gas and silicone oil during an exchange. In four of six serous detachments and three of four hemorrhagic detachments, the detachment originated from the infusion cannula site. Intraoperative infusion cannula retraction (5 of 12 cases) and blockage (2 of 12 cases) caused transient hypotony. All cases of serous, hemorrhagic, and gas detachment resolved without intervention. Cannulas were placed at various angles to the sclera in human donor eyes. Choroidal detachments were produced after injecting viscoelastic material through obliquely placed cannulas after 1 mm of retraction.
Conclusion: Infusion cannula retraction is an important mechanism and risk factor for the development of intraoperative choroidal detachment during 23-gauge vitrectomy. Precautions to prevent retraction and intraoperative repositioning may help avoid this complication.