Vitrectomy Trauma Pearl

Based on 14,523 injuries aIncludes all peripheral lesions (tear, necrotic hole, dialysis). All numbers are rounded

Based on 14,523 injuries aIncludes all peripheral lesions (tear, necrotic hole, dialysis). All numbers are rounded

A Controversial

Not all eyes with contusion-related traumatic vitreous hemorrhage require vitrectomy, which has its own complications; however, surgery is much easier, less risky, and more effective if secondary retinal complications are not yet present; early vitrectomy can also prevent retinal complications. It therefore remains an individual decision how early a surgeon decides to remove the vitreous hemorrhage.

2.9.3.5.2.1 Management Pearls for Vitrectomy for Trauma-induced Vitreous Hemorrhage

The surgeon should keep in mind the following:

• The difficulties and risks associated with the procedure are proportional to the severity of the hemorrhage.

• A severe hemorrhage makes it hard to determine what lays immediately behind the vitrectomy probe surrounded by nontransparent vitreous.

Even if the retina has been confirmed to be attached preoperatively17 and easy detachment of the posterior vitreous has been achieved in a large area, strong vitreoretinal adhesion may be present elsewhere. Careless vitreous removal can quickly lead to the development of a retinal break and detachment.

• Removal of the vitreous should be complete and compatible with safety.

• It may be difficult and dangerous to separate the vitreous in very young children; a judicious core vitrectomy is the compromise, leaving as thin a layer of cortical vitreous on the retina as possible (see Chap. 2.16).

• It is not always possible to completely remove the vitreous in the periphery; a thorough shaving is necessary in such cases.

O Pearl

Vitreous-related complications in a seriously injured eye originate from vitreous left behind, not from vitreous removed: vitrectomy should be as complete as possible.

• If fresh, red blood is encountered in increasing amounts during vitrectomy, this may be caused by acute intraoperative bleeding/8 It is also possible, however, that blood, previously trapped between vitreous layers or subhyaloidally, is now being freed.

• In vitreous containing older, yellow blood/9 streaks of red blood may also be present. The tissue resembles, and can be very difficult to distinguish from, a necrotic, detached retina. (See Chap. 2.12 for a special surgical technique to deal with the problem.)

• The posterior vitreous may not spontaneously detach, even if the hemorrhage has persisted for several months: in a recent study only a quarter of eyes showed spontaneous PVD after an average 38 days with IOFB injury [22]. The posterior cortical vitreous may be delineated by

17 Which may not be a reliable information (Fig. 1.9.5).

19 May persist for months or years, especially inferiorly.

the blood, though, making recognition and thus surgical detachment easier.

• The source of the hemorrhage is rarely found. Additional pathologies, however, are very common and must be meticulously sought.

• In the presence of a wound20 [17] or a disrupted lens [86], the risk of PVR is significantly higher (see below). It therefore appears reasonable to indicate vitrectomy early, especially if the injury was a rupture.

• The gravest danger in an eye with severe vitreous hemorrhage is the development of a retinal detachment.

TCave

In eyes with severe vitreous hemorrhage the B scan is often unable to reliably distinguish a PVD from a retinal detachment (see Fig. 1.9.5).

2.9.3.6 Subhyaloidal Hemorrhage21

Occasionally, blood is not dispersed in the gel itself but remains trapped between the retina and vitreous. Even though the media are clear, the patient registers severe visual loss if the blood is in front of the macula. The bleeding may occur as a result of direct trauma to the eye [66] or indirectly (e.g., Valsalva mechanism [37]; see Chap. 3.3)"

Regarding treatment, spontaneous dispersion of the blood can improve vision and help prevent PVR and retinal detachment; however, these complications can occur as early as within 5 weeks [68]. Treatment should therefore be considered early, especially if the hemorrhage is large and/or thick. The following options are available:

• SF6 alone [69] or in combination with TPA [19].

20 Especially if the wound was caused by rupture, rather than a laceration.

21 Technically, this is also a vitreous hemorrhage since the blood is in the vitreous cavity; however, because it does not enter the vitreous gel itself and has different implications, it is discussed separately.

22 Obviously, the differential diagnosis list includes nontraumatic causes as well.

• Vitrectomy is the definite treatment, indicated primarily if additional pathologies are present or the other modalities, listed above, have failed.

2.9.3.7 Contusion Retinopathy23

Areas of the retina may become opaque after a contusion. This condition is not caused by edema, as previously presumed, but by photoreceptor death [76], a finding recently confirmed on OCT [43].

• Acutely, a cloudy retina is noted, accompanied on occasion by hemorrhages. As in all contused eyes, choroidal rupture may also occur and full-thickness retinal necrosis may also develop [40]. Occasionally a retinal detachment follows [59]. If the macula is involved (contusion maculopathy), a full-thickness hole can form. The vision in the affected area is moderately to severely decreased.

• Subsequently, minor to major RPE disturbance is seen (Fig. 2.9.4). The vision may improve or remain unchanged.

There is no treatment for traumatic retinopathy; specific complications, as described above, require appropriate intervention. The surgeon must remain conservative regarding surgery if necrosis is present: the risk of postoperative retinal detachment is not negligible because retinal breaks can develop at the border of the contused area (see Chap. 2.10). Creating a protective barrier around the area with laser may be considered [79].

2.9.3.8 Chorioretinitis Sclopetaria

The name refers to a somewhat vaguely understood condition in which the eye sustains indirect damage from an object that penetrates the orbit with great momentum; the typical agent is a pellet or bullet. Other etiologies have also been described, including air-bag-related trauma, in which orbital penetration is unlikely [6]. The eye wall remains intact but various types of intraocular damage occur: tissue rupture; hemorrhage; and retinal

23 Also called commotio retinae or Berlin's edema.

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