3.10Referral of the Patient

Referring a patient must not be a simple instruction for him to “go and see someone at institution X” or ask the assistant to “send the patient to Dr. Y.” A detailed description of his condition must accompany the referral, which also has to be timely and very specific about why it is made; furthermore, the patient must be made aware of all these details.22

Pearl

VR surgery must never be about the surgeon’s ego (“if my peer could do it surely I also can”), only about the patient. The surgeon must be aware of his own limits and never try to stretch it into unchartered territory. If he, for whatever reason, is unable to do an optimal job, he should neither unnecessarily delay surgery nor should he do an incomplete job but refer the patient to a colleague/institution where all elements of success are available. If something truly unexpected emerges during surgery and the surgeon is unable to deal with it, it is best to stop surgery and not force it, but refer the patient as the lesser of two evils.

If the ophthalmologist, for whatever reason, is not willing to perform a surgery that the patient desires, referral is the only acceptable option (see Sect. 46.1.1).

3.11The Rest of the Eyeball…

As the knowledge base is growing,23 ophthalmologists are becoming highly specialized. A specialist, the joke goes, knows more and more about less and less; a highly specialized expert knows everything about nothing.

The VR surgeon must never fall into this trap. He does not have to be an expert in cataract or glaucoma surgery, but he must be knowledgeable in these fields24 so that he can complete his surgery even if issues not strictly related to VR surgery emerge.

22While writing this book, I saw a patient who was injured while chopping wood. He suffered a scleral rupture, traumatic cataract, and a VH. His wound was sutured and the ophthalmologist immediately had his assistant refer the patient to a well-equipped institution. Unfortunately, the assistant making the phone call failed to mention that the referral is for a fresh injury and simply asked for an appointment; the receiving institution also failed to ask the reason for the referral. The patient was scheduled for the next available date, which was 4 months later. He arrived with LP vision and an incarcerated, totally detached retina with severe PVR.

23I remember a cornea book with over 1,500 pages – and that was in 1978. Imagine a book today on the same topic and with the same detail: how long would it be?

24As well as in many other subspecialties such as uveitis or the cornea.

•The surgeon is able to reduce the level of tremor by having proper hand (wrist) support and by consciously and constantly paying attention to not squeezing the instruments he is holding.

–Squeezing non-squeezable instruments (see Sect. 13.2) such as the light pipe obviously serves no purpose, yet inexperienced surgeons do this instinctively. It should be part of the fellow’s training to fight this reflex.

•Not all squeezable instruments are the same.5 A good example is the disposable vs the permanent VR forceps (see Fig. 13.5). To operate the forceps the surgeon must squeeze its handle. The permanent forceps requires minimal force because

(1) the traveling distance of the handle from “jaws completely open” to “jaws completely closed” is short and (2) its resistance to the squeezing is low. Neither is true with the disposable forceps.6

Q and A

QWhat can the surgeon do if, despite his best efforts, tremor seems unstoppable and appears to prevent successful execution of a maneuver?

AAn individual decision is necessary whether the risk of attempting vs abandoning the maneuver is greater. Alternatively, the surgeon can try to switch the order of maneuvers and return to the delicate one (e.g., ILM peeling) later during the operation, first performing tasks that require less dexterity (e.g., scleral indentation and peripheral vitrectomy).

A final issue regarding tremor concerns its impact on the surgeon’s lifestyle. Can he repeatedly strain his hands/arms with hard physical work (daily weight lifting in the gym) or must he refrain from such activities?7

Again, the answer varies based on the individual surgeon. Some people are able to perform fine intravitreal work perfectly even after hard physical work; others have a major increase of tremor even after mild physical activity.8 Keep in mind, though, that repeated hard physical work does reduce the ability of one’s fingers to carry out fine manipulations. VR surgeons should not do heavy weight lifting on a long-term basis.

5It is the industry’s responsibility to design, based on surgeon feedback, squeezable instruments so that minimal force is necessary to operate them.

6A careful observer will notice that while at the onset of a difficult (long) ILM peeling the surgeon’s hands are steady, with time tremor develops. This is due to the force needed to squeeze the handle of the disposable forceps.

7My very first chief held an extreme view on this: “On the day of performing surgery the surgeon must not use his hands for anything strenuous.” He was a giant of a man with a petit wife; on the morning when he was scheduled to operate, his wife accompanied him to work and carried his briefcase for him. This was in the age of ICCE, light years from the era of ILM peeling.

8The same is true for caffeine intake.

4.2How Important Is Good Dexterity?

Again, it must be emphasized that the brain is the boss; the hands simply execute the instructions coming from the cortex. No matter how good a surgeon is with his hands: if the command is erroneous, the outcome is poor (see also

Chap. 1).

Very few people have two hands with equal dexterity; it is no different with VR surgeons. Typically, the surgeon is right-handed and would not be able to do the finest of maneuvers9 with his left hand unless undergoing rigorous, lengthy training.

•Typically, the surgeon’s nondominant hand is used for performing maneuvers that require only limited dexterity.

–In monomanual surgery, the nondominant hand usually holds the light pipe only. It may, however, be also needed for vitreous removal in the periphery in a phakic eye but also during laser cerclage (see below).

–In bimanual surgery, the nondominant hand is used for grasping a membrane, which the surgeon then cuts with an instrument operated by his dominant hand.

•Occasionally, the intraocular target area cannot be approached from the nasal side, even if this is where surgeon’s dominant hand is. Several options are possible.

–The task must and can be accomplished with the nondominant hand.10

–The task should but cannot be accomplished with the nondominant hand. In such cases some type of a compromise must be sought. For example, the patient has an extensive network of subretinal strands, including in the submacular area, which require removal because they do not allow retinal attachment (as clearly proven by a carefully performed air-test [see Sect. 31.1.2]). The surgeon may leave some of the subretinal membranes behind, alternate between use of the dominant and nondominant hands, use multiple retinotomies for access, or switch to a 20 g system.

Pearl

The surgeon himself may be surprised to realize how much he is able to accomplish with his nondominant hand. He should train the nondominant hand and thus improve its capability.

9Mostly, ILM peeling.

10One such scenario is lensectomy/phacofragmentation; this cannot be accomplished from the nasal side – the nose is in the way (see Sect. 38.2.1).

4.3Monoor Bimanual Surgery Is Preferable?

This is one of those questions to which there is no definite “this is better than that” answer.

•Most (experienced) surgeons can accomplish most tasks using only one working hand.

•Most surgical maneuvers can be performed using only one hand, with occasional help by the nondominant hand: the light pipe as an ancillary tool.11

•Using a fixed light source12 and having two working instruments in the eye has obvious advantages but also some drawbacks.

–Fixed lighting can never match the variety of illumination options the surgeonheld light pipe can provide by changing the location (switching hands), angle (shadows), and distance from the field (illumination power).

–The assistant can help by changing the angle of illumination via grabbing and redirecting the permanently fixed light. However, this makes rotating the eyeball more cumbersome.

–Self-illuminating instruments can eliminate or reduce the effects of these difficulties, but they introduce new ones: light reflex and additional shadow/s from the instruments themselves.

•Having two working instruments in the eye requires very close coordination between the two hands.13 Such coordination is as important an issue as the dexterity of the dominant hand.

–The surgeon is able to practice coordination between his two hands in many ways, outside the OR, by designing tasks that require fine bimanual movements.

–A great “live” test, with only a small risk of causing significant iatrogenic damage, is “window cleaning” of the dirty anterior surface of an IOL (see Sect. 25.2.3.2).

Pearl

Whether the VR surgeon uses one or two working hands to accomplish a certain task is an individual decision, not one that should be influenced by peer pressure (see Sect. 3.9). A surgeon who is unable to have the required close coordination between the two hands should stay with the monomanual technique.

11For example, separating the vitreous from the retina anterior to the equator (see Sect. 27.5.2).

12Light such as chandelier, twin, bullet etc.

13And, of course, between the two feet.

4.4Which Gauge?14

No patient ever asks the surgeon about the gauge he used during surgery; the one thing the patient is interested in whether the operation was successful or not. Selecting the gauge (20, or MIVS: 23, 25, 27) is an individual choice: whatever the surgeon feels most comfortable with to achieve the desired outcome. The crucial difference is not related to gauge size but to whether transconjunctival or conjunctivadissecting (traditional 20 g) surgery is performed (see Table 21.1 for more details).

•It may be advisable to mix the gauges in certain situations (see Sect. 32.4.1).

–An IOFB whose every dimension exceeds the inner diameter of the cannula (see Sect. 63.7.1).

–Intravitreal instruments with long blades are needed (PDR, subretinal membranes).

•The smaller the gauge, the higher the flow (vacuum) required to achieve tissue attraction.

–Tissue attraction means movement of the tissue toward the port.15 Conversely, at a given flow rate and at a given distance between retina and port, the risk of biting into the retina is higher with larger gauge probes.

•In general, the smaller the gauge, the slower the vitreous removal.16

–A probe with a smaller gauge also involves a higher chance of blockage by the aspirated material (such as lens, synchysis, hard membranes). The blockage requires flushing of the probe by the nurse or even replacement of the probe.

•Sutureless, spontaneous closure of the wound (and thus the prevention of postoperative hypotony), and healing (and thus prophylaxis of wound reopening) are proportionally faster with smaller gauges.

•In principle, the smaller the gauge, the less risk of causing a retinal break at the sclerotomy site, which risks the development of a postoperative RD.

I use almost exclusively 23 g because this offers most of the advantages of the 20 g instruments without significant compromise regarding functionality and the speed of the removal of vitreous, membranes, or lens material.17 Unless otherwise indicated, 23 g transconjunctival cannulas and instruments have been used throughout this book.

14The outer diameter of a 20 g instrument is 0.89 mm; 23 g, 0.72 mm; 25 g, 0.55 mm; 27 g, 0.40 mm. The scleral incisions need to be slightly longer than the diameter of the instruments inserted through them (diameter vs. surface area of the tool).

15The speed of movement also depends on the duty cycle (see Sect. 12.1.2.5).

16It also depends on machine characteristics (pump, flow/aspiration, duty cycle etc.) and setup (see Sect. 12.1).

17Exceptions include certain complex trauma cases or situations where instruments with a longer blade are preferred (see above).