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6.3 Preoperative Break Localization forScleral Buckling
Fig. 6.10 Method for remembering the orientation of the four mirrors of the three-mirror lens
6.3.2 Lincoff’s Rules
111
In May 1971, Dr. Lincoff published an original paper entitled “Finding the Retinal
Hole” in the renowned ophthalmology journal Archives of Ophthalmology. The
study included 1000 patients with RRD.By meticulously recording the shape of
retinal detachment and the location of primary breaks, and based on the mechanism
of subretinal uid production and the effect of gravity, a method for localizing
breaks was initially proposed.
In 1972, based on these research ndings, Lincoff proposed Lincoff’s Rules for
localizing primary retinal breaks (Fig.6.11), which remain an important component
of the scleral buckling system. With continued clinical experience, one gains a
deeper appreciation of their objectivity and accuracy. When applying these principles, the case most easily overlooked by beginners is that of a primary break located
superiorly presenting as inferior bullous detachment (Fig.6.12).
Lincoff’s Rules can be applied sequentially in the following scenarios.
1. When the affected eye is suitable for scleral buckling (e.g., young age, limited
detachment extent, etc.), but the surgeon has not clearly visualized the break
preoperatively using common examination methods such as wide-eld fundus
photography or indirect ophthalmoscopy.
2. In scenario (1), under the guidance of Lincoff’s Rules, use the three-mirror lens
combined with changes in the patient’s eye position to locate breaks in the
peripheral retina, paying particular attention to ora serrata dialysis or small retinal aps.
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6 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 1 (Scleral…
ab
cd
Fig. 6.11 Lincoff’s rules for nding primary retinal breaks. (a) Temporal superior or nasal
detachment: 98% of primary breaks are within 1.5 clock hours of the edge of the highest point. (b)
Total or superior detachment crossing the 12:00 meridian: 93% of breaks are at the 12:00 position
or in a triangular area with the ora serrata as the vertex, and the two sides of the triangular area
extend 1.5 clock hours to the left and right of the 12:00 position, respectively. (c) Inferior retinal
detachment: 95% of breaks are slightly inferior to the highest side of the detachment. (d) Inferior
and spherical detachment: if the detachment area presents a large blister-like bulge, the break is
usually located superiorly
3. If the retinal break remains unfound in scenario (2), after excluding exuda-
tive retinal detachment, use a cryoprobe to perform scleral indentation during surgeryand examine the peripheral retina with indirect ophthalmoscope,
with special attention to possible breaksat the ora serrata.
4. When no definite break is found in scenario (3), or when the refractive
media are opaque, apply Lincoff’s Rules directly and perform a wide
scleral buckle.
6.4 Basic Steps andPrecautions ofScleral Buckling
113
a b
Fig. 6.12 Inferior spherical retinal detachment. (a) When the patient undergoes fundus photogra-
phy in the sitting position, subretinal uid accumulates inferiorly due to gravity. According to
Lincoff’s Rules, the primary break should be located within the red dashed line in the superotemporal area. (b) When the patient is in the supine position, the conguration of the retinal detachment changes signicantly (video snapshot during PPV)
6.4 Basic Steps andPrecautions ofScleral Buckling
6.4.1 Understand Different Philosophies ofScleral Buckling
Since the mid-twentieth century, after extensive clinical validation, scleral buckling has developed into a standalone procedure with distinct approaches that differ
in somedetails. Among these, the most representative are the Lincoff schooland
the Schepens school. The major difference between them is whether subretinaldrainage is performed during surgery. Which approach is superior is something
every youngretinasurgeon must ultimately determine based on their own experience and insights.
Interestingly, despite the many differences in specic steps, the safety and efcacy of scleral buckling remain consistently high. The fundamental reason is that all
successful procedures adhere to basic principles: ① judicious selection of indications, and ② accurate localization and sealing of the primarybreaks.
When learning scleral buckling, we should thoroughly understand the characteristics of different approaches and, in clinical practice, prioritize safety and efcacy
as we explore the most suitable surgical strategy for ourselves.
6.4.2 Basic Steps ofScleral Buckling
The key to scleral buckling is preoperative design; the focus during surgery is avoiding complications. Below are the basic steps for scleral buckling without drainage.
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6 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 1 (Scleral…
1. Incise the conjunctiva to expose the sclera. Subconjunctival or sub-Tenon
anesthesia is not necessary. Although it aids analgesia and Tenon’s capsule
separation, it can cause bulging, hindering accurate conjunctival wound
alignment and postoperative healing. After limbal conjunctival incision, use
scissors to bluntly separate the intermuscular septum between adjacent rectus muscles, avoiding damage to the extraocular muscle sheaths to reduce
bleeding.
2. Sling the extraocular muscles. Slide a strabismus hook backward along the
scleral surface under the rectus muscle. The hook tip should always stay close
to the sclera to ensure the entire muscle insertion is engaged. After hooking the
muscle, pause to wipe away bleeding and conrm complete engagement
(Fig.6.13). Incomplete engagement may cause the scleral implant (especially
the encircling band) to pass through the muscle, leading to postoperative dysfunction—this must be strictly avoided.
3. Anterior chamber paracentesis. Use a drainage needle to release aqueous humor
and reduce intraocular pressure. Keep the needle tip within the anterior chamber
angle to avoid lens damage. Gently squeeze the eyeball to temporarily increase
Fig. 6.13 Elevation of the
extraocular muscle with a
strabismus hook. (a) The
strabismus hook does not
completely engage the
extraocular muscle, and the
hook splits the muscle
bers (green arrow). (b)
Withdraw the strabismus
hook, then re-elevate the
extraocular muscle.
Conrm that the muscle
has been completely
engaged as a whole; no
residual bers remain
unengaged. (green arrow)
a
b
6.4 Basic Steps andPrecautions ofScleral Buckling
115
pressure and promote aqueous outow (Fig.6.14). Release >0.2 mL of aqueous
humorto facilitate subsequent indentation and buckling. In patients with signicant vitreous liquefaction, the anterior chamber may not shallow noticeably, so
monitor intraocular pressure closely.
4. Localize the break under indirect ophthalmoscope. This step has a steep learning
curve. Intraoperative practice alone is insufcient; beginners should focus on
outpatient and ward training. Once mastered, indirect ophthalmoscopeprovides
excellent intraoperative visualization.
The surgeon wears an additional pair of sterile gloves or a disposable sterile
plastic lm bag (commonly used at Zhongshan Ophthalmic Center—faster
than gloves), then wearsthe indirect ophthalmoscope and adjusts tightness
and focus.
Focus adjustment steps: ① Extend left hand, close left eye, face palm toward
yourself, and adjust the right eyepiece until the light circle is fully cast on your
left palm. ② Extend right hand, close right eye, and adjust the left eyepiece until
the light circle is fully cast on your right palm. ③ Open both eyes—the complete
light circle will appear before you.
Hold a +20D aspheric lens in the left hand and the cryoprobe handle in the
right hand. Press the ocular wall back and forth from the periphery to the equator, carefully searching for breaks in the target area (Fig.6.15).
Fig. 6.14 Anterior
chamber paracentesis.
Attention should be paid to
avoiding accidental injury
to the iris and lens. By
squeezing the eyeball,
temporarily increase
intraocular pressure to
promote aqueous humor
outow
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6 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 1 (Scleral…
After accurate localization, ask the assistant to mark the break’s approximate
position on the scleral surface with a cautery or marker pen. This is especially
helpful for posterior breaks and long axial lengths, enabling accurate
explantsplacement (Fig.6.16).
5. Retinal cryopexy: Under indirect ophthalmoscope, step on the cryopexy foot
red and the outer retina becomes slightly whitened—stop immediately. The cryoprobe can thaw naturally or be dripped with water to accelerate thawing
(Fig.6.17).
Cryopexy can be performed simultaneously with break localization. Once the
break is accurately localized, cryopexy is not difcult. Do not freeze the RPE
layer directly beneath the break; instead, apply moderate freeze to the surrounding RPE at multiple points. The most common beginner mistake is excessive
cryopexy. Scleral cryopexy penetrates the entire ocular wall, potentially damaging the sclera, choroid, RPE, and neurosensory retina. Postoperative inammation leads to scar formation, which seals the break.
pedal. When the pressed area rapidly changes color—the choroid turns orange-
Fig. 6.15 Steps of break localization under indirect ophthalmoscope (a) Use the cryoprobe to
gently rotate the eyeball toward the intended freezing position (red arrow). The surgeon rst
observes the elevated peripheral retina through the headlight, keeping the indirect ophthalmoscope
light source and the peripheral retina aligned (two points form a line) (yellow arrow). (b) Maintain
the direction of eyeball rotation (red arrow). The surgeon places the aspheric lens in line with the
light source using the left hand, so that three points—indirect ophthalmoscope light source,
aspheric lens, and peripheral retina—are aligned (yellow arrow)
6.4 Basic Steps andPrecautions ofScleral Buckling
Fig. 6.16 Mark the
approximate position of
the break on the scleral
surface with a cautery
(green arrow)
Fig. 6.17 Surgical video
screenshot showing slight
whitening of the retina
under cryotherapy (green
arrow)
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This inammatory response is a double-edged sword. Follow the principle:
“accurate multiple points, lighter rather than heavier.” Excessive cryopexy
causes severe inammation, promoting PVR development, while atrophic
changes at the neuroepithelial layer may create new breaks at the cryopexy spot
edges, causing recurrent detachment and signicantly increasing reoperation
difculty (Fig.6.18).
118
Fig. 6.18 Chorioretinal
atrophy caused by
excessive cryotherapy
(within the red dashed
line), eventually leading to
recurrent retinal
detachment
6 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 1 (Scleral…
6. Placement of silicone explants: Explants xation typically uses 5–0 nylon
sutures, which can be pre-placed or directly sutured to the sclera. The anterior
suture is generally placed 9–10mm posterior tothe limbus. Beginners should
use a caliperto determine suture edges, ensuring good silicone buckle apposition
and reducing astigmatism.
Needle entry point selection is critical. The anterior point should avoid muscle insertions; the posterior point should avoid vortex veins to prevent bleeding.
Breaks located under a rectus muscle increase suturing difculty.
The assistant uses a retractor to fully expose the sclera. The surgeon holds the
corresponding muscle insertion with toothed forceps in the left hand, creating a
stable fulcrum to control needle depth and length.
To prevent scleral tearing at suture entry points, maintain appropriate needle
depth and a sufcient needle span, ensuring the scleral tissue has enough toughness to resist suture stress.
When inserting the needle, hold it in the right hand, gently press the scleral
surface, and enter at a 45° angle to reach the scleral lamella. The needle trajectory should be faintly visible on the scleral surface. When placing the posterior
suture, carefully identify the vortex vein and strictly avoid its adjacent area
(Fig.6.19).
During this process, maintain slight, slow wrist rotation to adapt to scleral
curvature, ensuring consistent needle depth—avoiding both suture slippage (too
shallow) and globe perforation (too deep).
6.4 Basic Steps andPrecautions ofScleral Buckling
119
The silicone explantwidth, suture span, and ligature tightness jointly determine buckle height. The commonly used siliconeexplanthas a 7mm base width
(nicknamed “tire” due to its appearance). #276 (groove on the side)(Fig. 6.20)
and #277 (central groove) tiresare the most commonly used. Beginners should
rst master these two styles.
The suture span should be 1–2mm wider than the silicone explant. For a
7mm widetirewith a 9mm suture span, tighten the suture until the two groove
margins are roughly apposed (Fig.6.21). After the rst knot, the assistant should
x it with microneedle holders to prevent loosening—otherwise, a denite
buckle is difcult to achieve. Figure 6.22 shows shape changes of the eye
wallwhen tightening the encircling band and silicone block.
The buckle arc should sufciently seal the break and surrounding degenerative area, generally extending ≥1 clock hour beyond each break edge. In practice, especially without drainage, retinal elevation and mobility make clock hour
judgment difcult. Beginners may appropriately extend bucklingrange to avoid
missing the break. If the bucklingheightis insufcient, add sutures to evenly
elevate the underlying sclera.
7. Check buckle position and height:Under indirect ophthalmoscope, use a cotton
swab or forceps to gently pull the eye toward the observation direction. Observe
whether the buckle position is slightly posterior to the break’s posterior edge,
andadjust as needed. Theoretically, the break’s posterior edge should be ≥1 PD
and ≤1.5 PD anterior to the buckle crest, but this is difcult to achieve precisely.
Beginners should at least conrm that the break’s posterior edge lies on the anterior slope of the buckle.
a b
Fig. 6.19 Anterior and posterior edge suture xation of the silicone explant. (a) The needle entry
point at the anterior edge should avoid the area around the muscle insertion. The needle entry depth
should allow the metal reection of the advancing needle to be faintly visible, and the span should
not be too small—preferably 2–3mm. (b) The needle entry point at the posterior edge should avoid
the vortex vein (green arrow) and its surrounding area
120
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Fig. 6.20 Silicone explant (#276), the width is 7 mm, and the central groove width is 2.5mm.
This groove serves two different functions: (1) When combined with encircling, the encircling
band passes through the groove, which helps to x the band in place. After the encircling band is
tightened, the posterior edge of the scleral buckle lies ush with the posterior edge of the silicone
explant; (2) When the silicone tireis used alone, tightening the xation sutures approximates the
two sides of the groove, creating a higher scleral buckle. In this conguration, the posterior edge
of the buckle lies ush with the midline of the groove
6 Surgical Intervention ofRhegmatogenous Retinal Detachment: Part 1 (Scleral…
Fig. 6.21 Tightening and xing the suture. (a) Tighten the suture to approximate the two sides of
the groove. (b) The assistant uses microneedle holderto secure the rst knot, preventing slippage
Additionally, continuously monitor intraocular pressure and optic disc perfusion. If optic disc arterial pulsation or cessation of arterial perfusion is observed,
perform anterior chamber paracentesis promptly to lower pressure. If pressure is
acting gas is generally not recommended at this stage.
low, inject balanced salt solution or ltered air into the vitreous cavity. Long-