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Major
Review
Does Scleral Buckling
Still Have A Role?
Thomas Cherian MS, Reesha K.R. DNB, Anju S. Raju DO
Introduction
Before the turn of the twentieth century, eyes with retinal
detachment (RD) were considered doomed. Contrary
to other branches of ophthalmology, such as cataract
extraction, the surgical treatment of retinal detachment was
still in its infancy, and surgical success rates were less than
five percent. From 1902 to 1921,Jules Gonin1 almost single
handedly changed the landscape of retinal detachment
surgery forever. He recognised that retinal break was the
cause and not the consequence as it was largely believed
at that time. He named the procedure ‘Ignipuncture’2, as
he cauterized the retina through the sclera with a very hot
pointed instrument.
The most difficult step in this procedure was the precise
localization of the retnal break. This localization became
more predictable with invention of the binocular indirect
ophthalmoscope by Charles Schepens in 19473. Two major
advances assisted the sealing of breaks to the Retinal
Pigment Epithelium. Meyer-Schwickerath4 developed
photocoagulation in the 1950 and Lincoff5 pioneered
modern cryopexy in the 1960.
Pars plana Vitrectomy (PPV) represented an entirely new
approach to the treatment of rhegmatogenous RD. It
was first reported by Robert Machemer6 in 1971. PPV
for rhegmatogenous RD was augmented by three other
innovations: silicone oil by Paul Cibis7 in 1962; fluid – air
exchange by Steven Charles in 1977 ; and perfluorocarbon
liquids by Stanley Chang8.
Retinal detachment occurs in 25,000 Americans each year9.
Patients suffering from RD are commonly nearsighted, have
had eye surgery, experienced ocular trauma, or have a family
history of retinal detachments. Retinal detachments also are
common after cataract removal. White males are at a greater
risk, as are people who are middle-aged or older. Patients
who already have had a retinal detachment also have a
greater chance for another detachment.
Some conditions, such as diabetes or Coats' disease
in children, make people more susceptible to retinal
detachments.
Scleral Buckling in the management
of Retinal Detachment
Scleral buckling is a surgical procedure in which a piece of
silicone plastic or sponge is sewn onto the sclera at the site
of a retinal tear to push the sclera toward the retinal tear. The
buckle holds the retina against the sclera until scarring seals
the tear. It also prevents fluid leakage which could cause
further retinal detachment10.
Scleral buckles come in many shapes and sizes. An encircling
band is a thin silicone band sewn around the circumference
of the sclera of the eye. Buckles are often placed under a
band to create a dimple on the eye wall11.
The scleral buckle is secured around the eyeball under the
conjunctiva. This moves the wall of the eye closer to the
detached retina. It also may move the retina closer to the
vitreous. This alteration in the relationships of the tissues
seems to allow the fluid which has formed under the retina
to be pumped out, and the retina to re-attach.
Evolution of Pars Plana Vitrectomy
In the earlier days, Vitrectomy12 was performed in cases in
which the surgeon's view of the damage was hindered. The
surgeon makes three incisions into the sclera, one for an
infusion, one for a light probe and the third for instruments
to cut and aspirate. The surgeon uses a tiny, guillotine-like
device to remove the vitreous, which he then replaces with
saline. After the removal, the surgeon may inject air or gas to
hold the retina in place13.
After, the surgeon is able to see the retina, he or she will
perform one of two companion procedures.
l
Laser photocoagulation. The laser is used when the
retinal tear is small or the detachment is slight. The surgeon
points the laser beam through a contact lens or a non contact
viewing system to burn the area around the retinal tear. The
laser creates scar tissue that will seal the hole and prevent
leakage. It requires no incision.
l
Cryopexy. Using a freezing probe, the surgeon freezes
the outer surface of the eye over the tear or detachment. The
inflammation caused by the freezing leads to scar formation
that seals the hole and prevents leakage. Cryopexy is used for
larger holes or detachments, and for areas that may be hard
to reach with a laser.
After the surgeon has performed laser photocoagulation or
cryopexy, he or she indents the affected area of the sclera with
silicone. The silicone, either in the form of a sponge or buckle,
closes the tear and reduces the eyeball's circumference. This
reduction prevents further pulling and separation of the
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Address for Correspondance: Little Flower Hospital, Angamaly
Thomas Cherian et al - Scleral Buckling
vitreous. Depending on the severity of the detachment or
hole, a buckle may be placed around the entire eyeball.
When the buckle is in place, the surgeon may drain subretinal
fluid that might interfere with the retina's reattachment.
After the fluid is drained, the surgeon will suture the buckle
into place and then cover it with the conjunctiva.
Temporary Buckles
For less severe detachments, the surgeon may choose a
temporary buckle that will be removed later. Usually, however,
the buckle remains in place for the patient's lifetime. It does
not interfere with vision. Scleral buckles in infants, however,
will need to be removed as the eyeball grows14.
Best visual acuity cannot be determined for at least six to
eight weeks after surgery. Full vision restoration depends on
the location and severity of the detachment.
Scar tissue, even pre-existing scar tissue, may interfere with
the retina's reattachment and the scleral buckling procedure
may have to be repeated. Scarring, along with infection, was
the most common complication15.
Other possible but infrequent complications include:
l
bleeding under the retina
l
cataract formation
l
double vision
l
glaucoma
l
vitreous hemorrhage
Patients may also become more nearsighted after the
procedure. In some instances, although the retina reattaches,
vision is not restored.
The National Institutes of Health reports that scleral buckling
has a success rate of 85–90%. Restored vision depends largely
on the location and extent of the detachment, and the length
of time before the detachment was repaired. Patients with a
peripheral detachment have a quicker recovery then those
patients whose detachment was located in the macula. The
longer the patient waits to have the detachment repaired,
the worse the prognosis16.
The danger of mortality and loss of vision depends on the
cause of the retinal detachment. Patients with Marfan
syndrome, pre-eclampsia and diabetes, for example, are
more at risk during the scleral buckling procedure than a
patient in relatively good health. The risk of surgery also rises
with the use of general anesthesia. Scleral buckling, however,
is considered a safe, successful procedure.
Scleral buckling is a standard surgical method to manage RD
after cataract surgery. Nevertheless, the outcomes of sclera
buckling in aphakic and pseudophakic eyes generally are
less favorable than in phakic eyes17. The range of anatomic
success varies from 61.5% to 80% in case of pseudophakic
and aphakic RD managed by Scleral buckling . Undiagnosed
retinal breaks are an important cause of failure in these
cases resulting from the smaller size and anterior location
of retinal breaks as well as incomplete fundus view because
of anterior or posterior capsular fibrosis, cortical remnants,
poor papillary dilatation, vitreous opacities, and optical
aberrations secondary to intra ocular lens itself. In addition
to unseen retinal breaks, proliferative vitreoretinopathy has
been shown to occur more frequently in pseudophakic and
aphakic RD18.
Pars Plana Vitrectomy as a Primary
Procedure for repair of Retinal Detachment
Advances in vitrectomy technique have encouraged
vitreoretinal surgeons to expand the role of primary pars
plana vitrectomy in the management of uncomplicated RDs.
Primary vitrectomy especially has been considered as first
line surgical treatment in cases of pseudophakic and aphakic
RD19. The rationale for such an approach includes the ability
to remove retained lens material, vitreous opacities, and
retinal pigment epithelial cells, while allowing controlled
drainage of subretinal fluid. Other potential advantages
of primary vitrectomy in these cases may be the ability to
visualize small retinal breaks with or without simultaneous
sclera depression and application of retinopexy. The absence
of risk of cataract formation is another reason for surgeons’
tendency to perform primary vitrectomy in aphakic and
pseudophakic eyes.
Ahmadieh et al designed a multicenter controlled clinical
trial to compare the anatomic and visual outcomes of sclera
buckling with primary vitrectomy alone in pseudophakic and
aphakic RD. The results showed no statistically significant
differences between the 2 treatment groups regarding the
single – operation retinal reattachment rate 6 month follow
up examinations. Patients in the buckle group had 28%
greater likelihood of anatomic success compared with those
in the vitrectomy group indicating no statistically significant
difference . Proliferative vitreoretinopathy was the main
cause of anatomic failure in both groups and occurred
independent of the surgical technique used. Final best
corrected visual acuity showed no statistically significant
difference between the 2 groups. There were no statistically
significant differences in rates of complications20.
The relationship between myopic RD and surgical success has
been in dispute. Burton and Lambert reported a somewhat
lower success rate in eyes with more than 4D of myopia21.
Eyes with high myopia may have a slightly lower success
rate when managed by scleral buckling. This in part results
from an increased risk of complications during placement
of scleral sutures because of marked scleral thinning and an
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Kerala Journal of Ophthalmology
increased risk of choroidal hemorrhage during drainage of
subretinal fluid. However, high myopia has been mentioned
as a risk factor for supra choroidal hemorrhage during pars
plana vitrectomy.
Isernhagen and Wilkinson evaluated the effect of
preoperative factors on final visual acuity after repair of
pseudophakic RD with scleral buckling. Preoperative visual
acuity was the most important variable. Macular involvement
is an important factor influencing vision after RD surgery.
Duration of macular involvement is one of the most
important variables associated with return of central vision22.
There is a significant decrease in visual recovery with macula
off detachment lasting longer than 1 week.
Macular pucker is a common finding after RD surgery. It has
been reported in 2% to 17% of detachment cases undergoing
sclera buckling20. Extensive RD and involvement of macula
have been noted to be associated with development of
macular pucker . Macular pucker also has been reported
as a frequent complication of primary vitrectomy for
pseudophakic and aphakic RD.
Refractive error changes after RD surgery can result in
anisometropia. In a study by Rubin, changes in refractive
error were related to the height of the sclera buckle and were
greater in phakic and aphakic eyes. Among the presumed
advantages of primary vitrectomy without an encircling
element over sclera buckling is the possibility of less induced
anisometropia21.
In most studies, early transient IOP rise was the most
common complication of primary vitrectomy combined with
fluid gas exchange. In the studies by Barz- Schmidt et al and
Speicher et al, this rate was reported to be 48% and 17.9%
respectively22.
Persistent extra ocular muscle dysfunction after buckle
surgery has been reported in upto 4%, and most cases
occurred in eyes with an encircling element. The rate of this
complication after vitrectomy was not reported in other
studies.
At the end of the previous decade, with the invention of
a variety of surgical techniques as substitutes for sclera
buckling to repair uncomplicated RD, Wilkinson wrote an
editorial entitled “ Wanted: Optimal Data Regarding Surgery
for Retinal Detachment.”
Primary vitrectomy without scleral buckle was not
more effective than conventional sclera buckling in the
management of uncomplicated RD in eyes with a history
of cataract extraction. No single surgical technique can
be considered as optimal and routine for all cases of
rhegmatogenous RD. It is noteworthy to consider some of the
following factors in selecting each of these options: the cost of
these operations, experience and capabilities of vitreoretinal
186
surgeons, and availability of proper instrumentation.
The Role of Scleral Buckling today
In children with a thick gel vitreous, scleral buckling may be
considered over PPV as the primary retinal reattachment
procedure. This holds good especially in traumatic retinal
detachments, where very often, the break is a retinal dialysis.
In phakic adults with rhegmatogenous RD, where the media
are clear and the break could be visualized, the number and
location of the breaks will probably decide on the surgical
technique to be adopted. A single break or breaks in a single
quadrant, especially in one of the inferior quadrants, where
a gas tamponade will be impractical, is best managed by
scleral buckling. A retina reattached by a scleral buckling
procedure is generally stable lifelong and gives a good post
operative visual recovery.
‘Macula on’ retinal detachments usually do well with scleral
buckling.
However, with the availability of PPV and its development as
a safe surgical procedure, along with the modern Vitrectomy
systems and viewing systems should prompt surgeons to
go for it where one is faced with a not so clear media, non
dilating pupil, proliferative vitreoretinopathy, posterior
breaks, multiple breaks in different quadrants, presence of
a macular hole, posterior staphyloma, giant retinal tears and
presence of a tractional element.
The new generation Vitreoretinal surgeons should be
adequately trained in scleral buckling surgery, or else, this
simple procedure will face the danger of extinction in the
years to come.
References
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