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7.6 Etiology andSurgical Treatment ofGiant Retinal Tear
151
7.6 Etiology andSurgical Treatment ofGiant Retinal Tear
7.6.1 Pathological Basis
Giant retinal tear (GRT) refers to a special type of retinal break spanning more than
3 clock hours (one quadrant). Although some breaks in rhegmatogenous retinal
detachment may also exceed 3 clock hours, most of them present as U-shaped tears.
Strictly speaking, such cases should not be classied as GRT but rather as typical
retinal tears, because their pathological basis is quite different from that of GRT.
Its pathological basis is that the posterior vitreous has undergone extensive liquefaction, while the adhesion between the peripheral vitreous and the retina remains
relatively tight. The shrinkage of the peripheral vitreous generates a broad area of
centripetal traction, whereas the posterior vitreous cannot provide stable support for
the corresponding retinal area. This imbalance of forces leads to extensive tearing
of the peripheral retina (Fig.7.12).
7.6.2 Surgical Principles
The use of heavy liquid has signicantly reduced the treatment difculty of GRT,
but beginners must still understand its pathological basis and formulate a rational
surgical strategy. The following four key points should be emphasized.
ab
Fig. 7.12 Schematic diagram of giant retinal tear. (a) Liquefaction of the posterior pole and
shrinkage of the peripheral vitreous cause extensive traction on the peripheral part. (b) Fundus
image of a giant retinal tear
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7 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 2 (Pars Plana…
1. Low difculty in removing posterior vitreous. Due to extensive liquefaction of
the posterior vitreous, PVD may already be present preoperatively, and inducing
PVD is relatively easy. However, because patients with GRT are generally
young, TAis recommended to conrm that no residual vitreous at the posterior pole.
2. High difculty in removing peripheral vitreous. The peripheral vitreous is dense
and exerts signicant traction on the anterior edge of the break. Complete
removal is challenging, and residual vitreous as well as iatrogenic breaks are
common risks. Even with a wide-angle lens, 360° vitrectomy must be performed
with the aid of scleral indentation.
3. Relieving the edge of the break is the key to the operation. The pathological
basis of GRT is an imbalance of vitreous forces, and this imbalance is most
severe at the edge of the break. The vitreous here is the densest and most tightly
adherent (Fig.7.13). Therefore, it must be completely removed to achieve full
retinal reattachment. However, because this area is located peripherally, expo-
-sure is difcult. Good assistant cooperation and the use of high -speed, low neg-
-ative pressure vitrectomy are essential to avoid iatrogenic breaks.
4. Repositioning the retinal apis the challenge. If heavy liquid is drained via air/
uidexchange, the pressure gradient decreases from the periphery to the posterior
pole, making the posterior edge of the GRT prone to curling and slippage. If silicone oil is then injected, the surgical difculty increases greatly and the postoperative outcome is signicantly compromised (Fig.7.14). Therefore, if silicone oil
tamponade is selected, oil/uid exchange technique is still recommended.
Fig. 7.13 Removing
dense vitreous at the corner
of the GRT under scleral
indentation
7.6 Etiology andSurgical Treatment ofGiant Retinal Tear
Fig. 7.14 After surgery
for GRT, the retinal ap
curls and slips, and OCT
also indicates epimacular
membrane and edema
(inside the white border)
153
7.6.3 Surgical Strategies
Due to the rapid onset and progression of GRT, once the macula becomes involved,
visual acuity drops sharply to hand motions. Many patients seek medical attention
promptly. The surgical strategy for GRT is primarily determined by the severity of
PVR, with grade C1 serving as the cutoff.
(1) PVR<C1 (See Sect. 11.2 of Chap. 11 for Grading)
For GRT without obvious PVR, the surgical principles are essentially the same as
described above, with the main difference being the choice of tamponade agents.
The author (Zhang) often use PPV withshort-termtamponade ofheavy liquid to
treat GRT without obvious PVR, with satisfactory surgicaloutcomes(Fig. 7.15).
The surgical strategy primarily involves the following key objectives: (1) Relieving
peripheral vitreous traction to ensure retinal stability; (2) Preventing heavy liquid
from inadvertently entering the subretinal space during injection; and (3) Maintaining
strict postoperative positioning and administering comprehensive anti-inammatory
treatment.Especially for superior GRT, the head should be slightly tilted back after
surgery(Fig. 7.16).7–10 days after the primary surgery, removethe heavy water. If
the retina is well reattached, there is no need to tamponade with gas or silicone
oil. Please refer to the website for detailed demonstration of the surgicalapproach:https://link.springer.com/article/10.1007/s10792-017-0613-4.
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7 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 2 (Pars Plana…
a b
Fig. 7.15 Postoperative fundus images of giant retinal tear. (a) Fundus photography on the rst
day after heavy liquid tamponade. (b) Fundus photography 1month after heavy liquid removal
Fig. 7.16 Preoperative
fundus image and
postoperative head
positioning for GRT. (a)
Preoperatively, a retinal
tear spanning
approximately 120°. (b)
After heavy liquid
tamponade, the patient is
instructed to maintain a
supine position with the
head slightly tilted back, as
the break is located in the
superior retina
a
b
7.7 Surgical Treatment ofRetinal Detachment Secondary toor Concomitant…
(2) PVR≥C1
Silicone oil tamponade is generally selected, and the surgical principles are the
same as described above. The main surgical challenge is to prevent curling and slippage of the posterior edge of the tear. Air/uid exchange is generally not recommended; instead, oil/uid exchange is preferred, as it better prevents curling and
slippage of the posterior edge. Some patients may additionally undergo scleral
encircling.
Although it is relatively challenging for beginners to nish a GRT surgery, the
complications are preventable and controllable. As long as the pathological basis is
well understood and the principles of heavy liquid use are followed, good outcomes
can usually be achieved.
155
7.7 Surgical Treatment ofRetinal Detachment Secondary
toor Concomitant withMacular Hole
Retinal detachment complicated by macular hole (MH-RD) is a complex form of
RRD.Retinal detachment with the macular hole as the primary break occurs predominantly in patients with high myopia. Some macular holes are secondary, mainly
appearing in patients with RRD who have marked vitreous liquefaction, high retinal
elevation, and a relatively long disease duration.
If the retinal detachment is extensive and highly elevated, or if the macular hole
is small in diameter, OCT may sometimes fail to detect a clear macular hole.
Preoperative examination should be carefully performed, especially when scleral
buckling is planned, to thoroughly rule out the presence of a macular hole.
MH-RD is characterized primarily by the following two features: (1) The detachment is centered on the macula, with the superior retina typically remaining attached
or exhibiting less detachment compared to the inferior retina; and (2) The detachment pattern does not follow Lincoff’s rules, potentially manifesting as a shallow
macular detachment or being complicated by concomitant choroidal detachment,
where the inferior detachment shows symmetrical elevation on both sides without a
distinct lateral slope (Fig.7.17).
For MH-RD secondary to high myopia, the three most signicant surgical challenges are: (1) Long axial length, which complicates maneuvers at the posterior
pole due to the increased working distance; (2) Residual vitreous cortex that is easily overlooked, necessitating careful staining and removal; and (3) Tight adhesion of
the peripheral vitreous, which makes thorough vitrectomy challenging and increases
the risk of iatrogenic retinal breaks.
To address these issues, the following surgical strategies may be adopted:
Complete removal of posterior vitreous. Double staining with TAand indocyanine green (ICG) can be used. TA stains only the vitreous, whereas ICG stains the
internal limiting membrane (ILM). If the ILM cannot be stained by ICG, it indicates
that the ILM is still covered by residual vitreous. Intraocular forceps can be used to
lift a ap from the stained area and expand the peeling range, which often allows
simultaneous peeling of the ILM and residual vitreous.
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7 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 2 (Pars Plana…
ab
Fig. 7.17 High myopia with MH-RD (a) Shallow detachment of the macula and inferior retina.
No obvious breakis visible in the macula on fundus photography, but OCT reveals a small macular
hole. Due to its small diameter, a retinotomy was created at the site indicated by the red arrow during surgery to drain subretinal uid. (b) Postoperative OCT conrms retinal reattachment and
closure of the macular hole
ab
Fig. 7.18 ILM peeling for high myopia with MH-RD. (a) Flap creationusing the “end-grasping”
technique. (b) Expanding the peeling range from the edge of the ILMap
Strategic peeling of the ILM.Flap lifting is the key, and surgery under heavy
liquid tamponade is generally not recommended.Because the posterior retina elevated with edema, the forceps can easily reach the retinal plane without causing
iatrogenic breaks. The surgeon lifts the ap with the distal end of the forceps near
the vascular arcade. Due to the highmobility of the underlying retina,the surgeon
may appropriately increase the grasping force.Once the ap is successfully lifted,
the peeling range can be easily expanded. The key to the procedure is “end-grasping”
of the ILM with the forceps (Fig.7.18).
ab
7.7 Surgical Treatment of Retinal Detachment Secondary to or Concomitant…
157
“Persistently” removing peripheral vitreous: Under TA staining, identify the
edge of the peripheral vitreous. Use a vitrectomy probe (with high cutting rate and
low vacuum) to begin theshaving. Iatrogenic breaks in the inferior quadrant should
be avoided as much as possible, because silicone oil tamponade provides poor sealing effectfor inferior breaks.
Selecting the appropriate subretinal uid drainage method: Fluid/air exchange is
generally preferred. If the macular hole is large, drainage can be performed directly
through the hole. However, if the hole is small, direct drainage may be difcult and
could enlarge the hole. In such cases, a drainage retinotomy can be created in the
-mid peripheral detached retina. The retinotomy should preferably be located in the
superior quadrant; if the superior retina is not detached, choose a location where
silicone oil can effectively tamponade postoperatively.
Adequate drainage ofsubretinal uid around the macular hole: Before injecting
silicone oil, subretinal uid in the macular area should be completely drained
off,leaving the hole in a “dry” state. Silicone oil should then be injected quickly to
cover the macular hole, preventing reaccumulation of uid at the posterior pole.
This strategy can improve thesuccess rate and help avoid recurrent detachment of
the hole.
Preventing pupillary block: Some patients are prone to pupillary block after surgery, and even silicone oil migration into the anterior chamber. Close observation
and timely treatment are required. In pseudophakic eyes, an inferior Ando iridectomy can be created during surgery for.
If the macular hole remains in a at-open state after surgery, the probability of
retinal re-detachment following silicone oil removal increases. For patients with a
large macular hole (Fig.7.19), an inverted ILMap can be used to cover the macular hole(Fig. 7.20).
Finally, it should be noted that if the retina is completely reattached after surgery but the macular hole is not closed (at-open state), some patients will have
symptoms of central scotoma. However, this should not be considered a surgical
failure, and explanations should be provided to the patient before and after surgery.
Fig. 7.19 Preoperative and postoperative fundus images of MH-RD. (a) Preoperatively, retinal
detachment is visible, with the primary retinal break located in the superior peripheral area (white
arrow), and OCT shows a macular hole. (b) In the postoperative silicone oil tamponade state, the
retina is at and the hole is closed
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7 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 2 (Pars Plana…
a
b
c
Fig. 7.20 InvertedILM ap tocover MH in MH-RD. (a) After ILM staining, rst lift a ap from
a position far from the macula to create a wide-based and large ILM ap. (b) Before draining
subretinal uid from the macular hole through air/uid exchange, gently atten the ILM ap to its
original position to avoid damage and aspiration by the ute needle. (c) When the macular hole is
completely “dry,” use intraocular forceps to cover the macular hole with the ILM ap, followed by
immediate silicone oil injection
7.8 How toModify theSurgical Approach When Primary
Break(s) Cannot BeFound
Approximately 5% of patients with RRD, especially young pseudophakic patients,
have no identiable primary retinal break either preoperatively or intraoperatively.
In such cases, exudative causes should rst be ruled out, and a surgical strategy
should be formulated based on thevitreous status. The following steps can be taken:
Rule out macular hole. If PVR is severe or the posterior pole detachment is high,
a macular hole may be masked.
7.9 Additional Steps toEnsure Possibly Higher Long-Term Reattachment Rate
Infer break location using Lincoff’s rule. As long as a primary break exists, the
morphology of retinal detachment will follow Lincoff’s rule, which can be used to
estimate the approximate break location.
Formulate a surgical plan based on vitreous status. Scleral buckling should not
be overlooked. If the vitreous is relatively clear and the patient is young, the break
location can be inferred using Lincoff’s rule, and scleral buckling can be attempted
rst. This approach has inherent advantages, particularly for inferior retinal detachment, and can often avoid internal surgery.
Select a good position to createa retinal break forsubretinal uid drainage.An
incision should be made at a slightly superior and posterior location within the
detached area for drainage.The tip of a uteneedle can be used to aspirate intermittently and repeatedly to create a small break. Subretinal uid can then be drained via
air/uid exchange. Laser photocoagulation should be applied to the peripheral retina, as there may be tinybreaks.
If the retinal mobility is good, long-acting gas tamponade is sufcient, and silicone oil can be used in a few cases. If the inferior retinal mobility is poor, auxiliary
scleral buckling can be performed.
159
7.9 Additional Steps toEnsure Possibly Higher Long-Term
Reattachment Rate
Although the long-term (>6months) anatomical success rate of noncomplex RRD
has exceeded 90%, maximizing the long-term prognosis is still the constant goal of
all retina surgeons. We mainly try to improve the long-term healing rate of RRD
through two methods:
7.9.1 360° Laser Encircling
There remains considerable controversy regarding the necessity and effectiveness
of this technique. After closing all primary breaks, if the ora serrata is visible under
-a wide angle lens, two to three rows of laser photocoagulation may be applied to the
peripheral retina near the ora serrata without scleral indentation. This may benet
patients with high myopia, weak ora serrata, or multiple peripheral degenerative
areas (Fig.7.21).
7.9.2 Scleral Buckling
In fact, the use of adjunctive scleral buckling for routine RRD is gradually decreasing. However, it still plays a positive role in retinal detachment with multiple primary breaks in the inferior quadrant. Numerous clinical studies have shown that
adjunctive scleral buckling can improve the surgical success rate of RRD, and therefore beginners should not overlook its importance (Fig.7.22). Adjunctive scleral
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7 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 2 (Pars Plana…
buckling may be performed either before or after PPV.If gas tamponade is planned
postoperatively, it is recommended to perform buckling before; if silicone oil tamponade is planned, buckling should be performed after.
Fig. 7.21 Laser encircling. Beginners performing 360° laser encircling should pay attention to the
following details: (1) Protect the lens; (2) Strictly control the total amount of laser. (3) Avoid creating laser-induced breaks
Fig. 7.22 Postoperative
fundus photograph of a
patient with retinal
detachment due to inferior
breaks. PPV with silicone
oil tamponade and
scleralencircling was
performed to improve
surgical success