40.2Retinal Tear

The risk is mostly associated with the failure to recognize the tear intraoperatively. See Fig. 40.1 for management suggestions. Unlike in 20 g surgery, the breaks in MIVS are found posterior to the vitreous base: the cannulas protect against the risk at the vitreous base since the instruments are not pushed through the gel repeatedly. The risk due to PVD, however, remains identical.

Retinal tear

Fig. 40.1 Decision-making tree about the intraoperative management of an iatrogenic retinal tear. More details are presented in Chapters 26, 27, and 30

40.3Reopening of a Posterior Scleral Wound

If the posterior wound is large, unsutured, and PPV is done very early (see Table 63.1), the posterior wound may reopen. It is recognized by large radial folds,3 which are caused by BSS that has been entering the orbit and compresses the eye from behind.4

•Stop the infusion.

•Switch to silicone oil, without going to air first.

– Do not use PFCL.

•Discontinue the operation. The intraorbital fluid is likely to disappear by the next day, and surgery can resume then.

Pearl

The posterior wound is unlikely to reopen if the IOP is not raised and the wound edges are not touched by the surgeon.

3These are not retinal or choroidal but scleral folds.

4It is highly unlikely that the retina will be “blown” into the orbit.

•Alternatively, you can try suturing the scleral wound from inside.

–Bimanual surgery is needed – insert a chandelier light.

–Use just enough infusion to keep the globe inflated, but try not to force more BSS in the orbit. Cohesive viscoelastic may be used to cover the entire area.

–Diathermize the retina and choroid around the wound edges to prevent hemorrhage during and proliferation after the operation (see Sect. 33.3).

–Use 9-0 nylon sutures and two crocodile forceps to close the wound and tie the sutures.

–Once the wound is closed, carry on with the vitrectomy as usual.

40.4Lens/IOL Trauma

True intraoperative lens trauma is rare in experienced hands, and the consequences are not terrible even if it does occur. The management depends on whether only a touch occurred or the capsule has been violated (see Sect. 25.2.3.1).

The IOL may get dislocated, which is another very rare complication (see Chap. 44 and Sect. 38.6). If there is sufficient capsular support and the IOL is only subluxated, the IOL may be repositioned. A needle inserted in the frontal plane (see Fig. 40.2.) helps prevent the IOL from luxated into the vitreous while the anterior manipulations are carried out.

Fig. 40.2 Prevention of IOL luxation. A 27 g needle, typically bent just behind its cone, is inserted across the pars plana. It provides mechanical support for the IOL while the anterior vitrectomy is carried out, removing the gel from the AC and behind the remnant of the posterior capsule. Once the IOL is securely repositioned (or removed if the capsular support is insufficient), the needle is withdrawn