"Caution with choroidals" - choose the right one at right time

Abstract

Background: During the repair of rhegmatogenous retinal detachment (RRD), pre-existing or intraoperative sudden choroidal detachment (CD), often compromises the surgical outcome and visual prognosis.

Purpose: To describe video-guided specific approaches for pre-existing or sudden intraoperative CDs during the repair of RRDs.

Synopsis: Cannula-guided choroidal drainage is necessary to decrease the severity of pre-existing CDs. Complex RRD with massive hemorrhagic CD often warrants a similar approach. Intraoperative sudden CD can be due to sudden hypotony because of a disproportionate increase in outflow due to high suction or a decrease in inflow due to kinking or blockade of the infusion tube/tip by vitreous/detached retina. It may also be due to the leakage around the cannulas in the eyes with thin sclera. Rarely accidental air entry inside the suprachoroidal space due to inadvertent slippage of a non-sutured infusion cannula tip can precipitate sudden kissing CD. If the air infusion pressure is 40 mm Hg or more, this suprachoroidal air can cause a tear in the vortex vein ampullae, and air enters inside the vortex vein. Then, it may go via ophthalmic veins to the cavernous sinus or via pterygoid plexus to the internal jugular vein, superior vena cava, and the right atrium, and can cause pulmonary embolism or less likely occlude systemic arteries via the foramen ovale. This possible life-threatening Venous Air Embolism (VAE), occurring concurrently with Ocular Air Fluid Exchange (OAFE) during vitrectomy, is known as "PRESUMED AIR BY VITRECTOMY EMBOLISATION (PAVE)". Immediate stoppage of the air infusion and removing it can prevent this accidental PAVE and eventual death. In this era of MIVS, this risk is likely to be higher than in previous decades, when infusion cannulas were used to be sutured to the sclera.

Highlights: The video describes the strategies for treating pre-existing CD along with RRDs and managing sudden intra-operative CDs, sometimes to prevent PAVE in cases of suprachoroidal air entry.

Video link: https://youtu.be/fEstbqVkXH4.