The list of conditions amenable for VR surgery is long and growing. Each condition has its own arguments in favor of and against surgery, which need to be discussed with the patient so that he, together with the surgeon, can come to a decision (see Chap. 5). In this chapter only a few basic thoughts regarding indications are discussed, strictly from a medical standpoint.1

8.1The Argument in Favor of Surgery

Why surgery should be done is rather obvious: it promises the chance of visual improvement, the prevention of its worsening, or, as a minimum, the preservation of the globe.

Q&A

Q Can the surgeon promise functional success?

ANever. With certain indications such as floaters, the chances of improvement are excellent, but still not 100%. All the surgeon can promise is to try his very best to help. Surgeons cannot restore function; they restore anatomy, with a reasonable hope that function will follow. It is also not possible to predict how much improvement will occur. Statistically, one can give a general prognostic figure, but the surgeon must always emphasize that the statistical average or range is not necessarily true for that particular person or operation.

1 In other words, what the surgeon might prefer if the final decision were not up to the patient. Sadly, in real life often this is what happens, as if the eye were owned by the physician.

F. Kuhn, Vitreoretinal Surgery: Strategies and Tactics,

DOI 10.1007/978-3-319-19479-0_8

•Every time a medical intervention, whether surgical or not, is considered, one of the key questions is the risk-benefit ratio. No intervention should be performed, even at the specific request of the patient, if the former is greater than the latter (see Table 5.1).

–Usually it is relatively easy to determine whether the chance of improving (preserving) function is indeed higher than the risk of deterioration due to a complication (or natural history).

–There are exceptions to this general rule. Think about a patient who has retinitis pigmentosa, has lost vision in one eye, and develops an EMP in the only eye (see Table 1.1).2

•The benefits a successful surgery brings3 are obvious: an attached retina’s function should improve, a vitreous is no longer opaque, the macula is smooth again etc.

–Often the patient “sees the difference” the next day; in other cases he is warned that his vision may be even worse than preoperatively but that this is temporary (e.g., gas tamponade, see Sect. 35.2.2).

–More difficult to appreciate is an operation that does not improve function, “only” preserves the current status; such an indication requires even more extensive counseling than usual.

Pearl

A somewhat similar question is whether to perform a certain surgical maneuver (e.g., laser around a posterior retinotomy, see Sect. 30.3.1) if it is done not because it has proved to be necessary but because the surgeon will “sleep better if he did it.” This argument is not totally wrong: as long as the maneuver has a rationale (at least some scientific merit) and its risk is low, the surgeon can claim, should the disease course turn for the worse, that he tried everything (instead of having to say: “If only I had done that maneuver in the first place…”).

•“Beauty” should in general not serve as a justification for VR surgery4 or for an intraocular maneuver. The goal is not to restore perfect anatomy but to improve function via restoring (enough) anatomy. A membrane in PDR need not be removed in its entirety so as for the fundus to look perfect; leaving harmless5 membrane stumps on the retina often makes more sense than risking iatrogenic retinal breaks by forced “beautification” (see Sect. 32.3.2).

A special case is an eye with full visual acuity but with a distinct anatomical and functional abnormality; this is discussed in Chap. 46.

2This is also a good example why the patient, not the surgeon, should have the final say indicating the operation. Imagine if it was the surgeon who convinced the patient that he should accept surgery and something goes wrong. The surgeon will feel guilty and the patient may sue him.

3And every surgery starts with the premise that as a minimum, it has a chance of success.

4Exceptions do exist. Removal of a calcified, white lens from a blind eye is absolutely justified if the person is bothered by it.

5That is, deprived of any traction potential.

8.2The Argument Against Surgery6

Q&A

Q What if the patient wants a “guaranty” of success?

ANone can be offered. If a patient asks me for a guaranty, I ask them the following: Do you have a guaranty that as you exit the building after the examination, a brick would not fall and hit you in the head? Most people are shocked to hear this first, but then realize that no such guaranty is possible. It is highly unlikely that a brick would hit them, but it is not entirely impossible.

It is very uncommon7 today that a major intraoperative complication, causing permanent visual loss, occurs. Most of the serious complications present in the early or late postoperative period, but these complications should always be on the surgeon’s mind before undertaking the operation.

Pearl

The reason why the surgeon should operate is very obvious before the operation; the reason why he should not have becomes obvious only after the operation. Still, for a surgeon to choose “observation” for a condition that is amenable to surgery is more difficult than to opt for the intervention.

Observation is nevertheless a perfectly acceptable option in many cases – except when it is chosen as a convenience to the surgeon,8 not because this is the most reasonable alternative for the patient.

8.3The Age of the Patient

Some surgeons are much more willing to forgo surgery if the patient is “old.”9

Pearl

Old age of the patient should, as a general rule, not be used as an excuse to disqualify him from surgery. Acceptable arguments include his systemic condition and life expectancy.

6As Hippocrates warned: “First, do no harm.”

7What “very uncommon” means is that the chance is more than zero.

8A famous American humorist was once asked why he stopped writing his syndicated weekly newspaper column. His answer was: “I realized that it’s much easier not to write the column than to write it.”

9Of course, the definition of “old” is very subjective. A surgeon in his 30s may deem so a 60-year- old patient; for a surgeon in his mid-50s, a 70-year-old patient is still “relatively young”.

On the other side of the spectrum is the very young patient.10 Children with conditions that, if untreated, invariably lead to amblyopia11 should be offered surgery as early as possible, and the family/guardian must be advised about the need for antiamblyopia treatment.

8.4The Condition of the Fellow Eye

For many surgeons, this can be an important, even decisive, factor: they are much more reluctant to offer surgery, for instance, to a patient with tractional diabetic RD involving the macula if the other eye has decent vision.

My personal issue with this attitude is its inherent assumption that some type of a warranty is in effect for the fellow eye: it will never develop a sight-threatening disease.12

•Do not deny PPV just because the fellow eye is healthy or has good function.

•Conversely, do not recommend PPV if you do so only because the fellow eye has poor (no) vision.

–The prognosis for the eye undergoing PPV is the same whether the patient is monocular or not. However, the prognosis for the person is very different if he is monocular: the stakes are much higher.

Pearl

Operating on a monocular patient does have certain implications for both the patient and surgeon (see Sect. 3.5 and 18.2), and these must be seriously considered when the decision whether to operate is made.

10As described in Chap. 41, surgery on young patients is generally more difficult than on adults; the fellow should therefore not “jump into” operating on a child’s eye without proper experience.

11Persistent hyperplastic primary vitreous, Toxocara-related chorioretinal scarring, late stages of ROP etc.

12In real life Murphy’s law applies: if a serious condition develops, it occurs in the “good eye” and at a time when it is too late to attempt repair of the first eye. It is very sad for the surgeon and patient to face their guilty feeling; the remorse cannot reverse what had been so casually given up earlier.

Of all the pieces on the surgeon’s decision-making palette, the easiest to influence is the time when the surgery is to be done. In many conditions delaying the operation means that the vision will gradually worsen, and the worse the visual acuity at the time of the operation, the less likely that the improvement will fully restore what has been lost.1

Pearl

As a general rule (exceptions exist), the earlier surgery is performed, the easier the procedure technically is and the better the prognosis.

Still, it is impossible to issue blanket advice about the urgency of VR surgery,2 and every decision should be an individualized one tailored to the particular circumstances. Table 9.1 shows the decision-making process in various conditions and Fig. 9.1 the strategic thinking in timing decisions.

One issue to consider in each case if the surgery is elective is whether certain systemic medications need to be suspended or modified preoperatively. This is briefly discussed in Sect. 40.1.

1 The surgeon can describe this to the patient by comparing the situation to climbing a ladder (with the steps representing visual acuity levels). If you have the strength to climb only a limited number of steps (representing the functional improvement one can hope to achieve) and you start at the bottom of a rather tall ladder, you will never be able to get to the top again. However, if you start climbing when you are down from the top by only a few steps, you can reasonably hope to be able to make it fully back up again.

2As mentioned in Chaps. 5 and 8, the final decision should rest with the patient anyway.

F. Kuhn, Vitreoretinal Surgery: Strategies and Tactics,

DOI 10.1007/978-3-319-19479-0_9

aUnless otherwise indicated, more information is found in the relevant chapters in Part V. The conditions are in alphabetical order.

bIf pupillary block occurs, the IOP can rapidly become so high that irreversible optic nerve damage threatens.

cAs opposed to the much limited role for surgery, and a limited one at that, in the Endophthalmitis Vitrectomy Study.

(continued)

Table 9.1 (continued)

dDegenerated, swollen, rigid red blood cells that have difficulty exiting through the trabecular meshwork because of their size. They have a khaki color and can actually be seen in the AC at the slit lamp at high magnification. AC irrigation brings only temporary relief since the vitreous gel is the reservoir of the ghost cells.

eRisk of corneal “blood staining”.

fI do not discuss here the nonsurgical treatment options.

gWhether the macula is off or on, although there is more urgency in the latter scenario.

hFor example, a delay until Monday morning is acceptable if the patient presented on Friday afternoon, but bedrest is recommended.

iEven then, the subretinal fluid’s composition is different (two examples include optic pit and central serous chorioretinopathy) from that seen in other RDs, and the macula is able to tolerate having been detached for extended periods.

jOr an alternative treatment such as tPA and gas injection. kDrainage of the blood is not discussed here.

lNot to mention that it means loss of vision for the patient.

Urgent or Elective surgery Yes No emergency

surgery

Fig. 9.1 Strategic thinking regarding the timing of surgery in VR diseases. If a condition is not expected to improve spontaneously, the surgical option should always be considered. The risk of rapid worsening makes the surgery urgent; otherwise, there is a reasonable argument for some delay, but how long this should be depends on many factors (not listed here). I typically tell my patients to look at the issue in a rational way: if we know that eventually surgery will become necessary, is there any gain by delaying it, or is there potential harm? In the latter case delaying the intervention has only risks but no benefit