–During peeling, the membrane will prove to be very adherent to, or simply located on top of, the retina.31

–During peeling, the membrane will prove to be rigid or fluffy. The latter is much more difficult to peel because the membrane is elastic (composed mostly of cells). Occasionally it can give the surgeon the shivers since it resembles “peeling” of the nerve fibers (see above).

32.2.2 Removal Technique

32.2.2.1 Staining or Not?

Proper staining (see Sect. 34.2) helps identify the membrane and helps both in tactical decision-making and its execution.32 My personal decision-making related to the timing of staining is shown in Fig. 32.9a; b is a clinical example of the staining being useful.

32.2.2.2 Instrumentation

As a first maneuver, the membrane can be separated from the retinal surface by any of these tools.

•Forceps. Used in most cases by most surgeons; unlike with ILM removal, various forceps designs are acceptable, especially if the membrane is not too thin.

•Scraper. It is very helpful to “pick up” a membrane whose border is inconspicuous.33

•Barbed needle. The hook is turned downward to pick up the membrane.34

32.2.2.3 Location of the Point of Attack

By the time the surgeon selects this location, he already must have decided whether to carry out the membrane peeling in a centripetal or centrifugal direction (see below).

Since I always try to progress in a centripetal fashion, I attack the membrane at its edge, far away from the fovea.

•Forceps: Select an area where the membrane is rather thick, grab, and gently lift it (see Fig. 32.10).

31The variables of most other “pairs” are usually visible and can be determined preoperatively; the strength of the adherence, however, is not known until the membrane is actually being peeled.

32I use “negative” staining: the ICG will stain the ILM, but not the overlying EMP, giving a relieflike image.

33The scraper is used by some surgeons to remove the entire membrane. While it is technically possible, there are inherent dangers. As mentioned above, the downward pressure is difficult to control, and areas of strong membrane-to-retina adhesion will remain hidden from view. The ILM or the full thickness of the retina may get torn.

34It can then be turned upward and lift/separate the membrane, occasionally even complete the procedure (see Figs. 13.8e, f).

larger areas, and include the fovea as well. The line of advancing separation between membrane and retina is rather large, making it difficult if not impossible to simultaneously determine whether retinal damage is occurring. The membrane will surely be removed, but the surgeon sacrificed control for the sake of convenience.

•With centripetal peeling, the surgeon gradually separates the membrane at its edges, 360°, with the fovea being the last phase. The area of advancing separation between membrane and retina is very small – and the size of the separation line is entirely controlled by the surgeon – making it easy to notice if the adhesion is too strong. If it is, scissors or the probe must be used.

c

Fig. 32.11 Retinal fold masquerading as an EMP. (a) The dashed white line shows an area temporal to the macula, with several full-thickness retinal folds caused by the contracting EMP. The membrane itself, however, is barely visible; only a small light reflex gives it away (white arrow). What appears to be the thick edge of the EMP is in fact another superiorly located retinal fold (thick black arrows). (b) The fluffy EMP is being removed; the large superior fold is still visible. (c) With the EMP removed, the light reflex and most of the temporal folds have disappeared; the large superior fold is still rather conspicuous. Once the ILM is also peeled, this fold will rapidly smoothen out