3. Treatment guidelines for retinal breaks
Type of
break
Phakic High myopia Fellow eye Aphakia /
pseudophaki
a
HST
symptomatic
treat treat treat treat
HST
asymptomatic
observe Treat some treat Treat some
Operculated
symptomatic
Treat some treat treat treat
Operculated
asymptomatic
observe Treat few observe observe
Round hole
asymptomatic
observe observe Treat some observe
Lattice
without holes
observe observe Treat some
unless lattice
more than 6
clock hours
observe
Lattice with
round holes
observe observe observe
4. Selection of the surgical procedure to re-attach
the retina with least morbidity.
Scleral buckling.
Vitrectomy( classical/sutureless/using gas/silicone
oil & if needed , an encircling silicone band)
Pneumatic retinopexy.
5. METHOD Reattachment
rate
limitations/complicati
ons
benefits
Scleral
buckling
94% Morbidity,infection,buckle
extrusion,ocular motility
disturbances.
Excellent long term
anatomic
success,good visual
outcomes.
Pars plana
vitrectomy
71-92%(primary
success rate)
95%(final
success rate)
Iatrogenic retinal
breaks,PVR,lens
trauma,cataract
progression.
Visualization of all
breaks,removal of
opacities/synechiae
,anatomic success
in complicated
detachments.
Pneumatic
retinopexy
64%(primary
success rate)
91%(final success
rate)
Use limited to
uncomplicated RRD with
sup. Breaks,need for post
op positioning ,creation of
iatrogenic breaks.
In- office
procedure,minimall
y invasive,reduced
recovery
time,better post-op
VA.
6. Scleral buckling
The term “buckle” refers to deformation of a
structure understress. Sometimes the term
“buckle” is used synonymously with some
form of encircling explant, while others use
the term to describe local explants.
7. mechanics
Biomechanics :alters the shape of the eye
depending on the type of buckling
material.
The location
The tension of the scleral sutures.
The circumferential tightening of an encircling buckle.
Changes after buckling:- AL change
astigmatism
volume of the eye
patient compliance
scleral buckle placement
12. Pre operative assesment
Macular involvement
Features suggesting that the retinal detachment is
nonrhegmatogenous .
The presence of vitreous detachment
Significant ocular co-pathology, which may affect
management (e.g., glaucomatous optic neuropathy,
aphakia with vitreous in the anterior chamber, a
history of strabismus surgery)
The number and position of the retinal breaks
23. RETINOPEXY
The indent from the explants helps in closing the
retinal breaks .
This is done in order to increase the bond between
retina & retinal pigment epithelium .
Even if the indent disappears.
24. CRYOTHERAPY
AIM: to produce freezing of
healthy retina surrounding all
the retinal breaks.
OBSERVATIONS:- whitening
of the retina after few seconds.
Break is seen as the darker area
over the white freezed area
which confirms the success of
cryo.
36. CUT DOWN TECHNIQUE
A scleral incision 3 mm in length is made in the
sclera, repeatedly spreading the edges, then incising
the base of the resulting groove the choroid becomes
increasingly visible in the base of the incision. Finally
a small knuckle of bare choroid protrudes slightly
40. Post operative complications:
Recurrent retinal detachment
Glaucoma
Presence of epiretinal membrane
Extrusion /infection
41.
42. Pneumato retinopexy
History:-
Ohm performed the first intravitreal air injection for
retinal detachment in 1911.
In 1938 rosengren
In 1973 norton reported use of sulfur hexafloride SF6
At 1985 meeting of american association of
ophthalmology Hilton & Grizard introduced the term
“PNEUMATIC RETINOPEXY”
43. BASIC PRINCIPLES
The value of intraocular bubble is based on three
features:
Buoyancy
Surface tension
Isolation of retinal tears from intraocular contents.
SF6{sulphur hexafluoride} & C3F8{carbon
perfluoropropane}
USFDA approved in 1993 for use in PR.
44.
45. Gases triad in viteroretinal surgery
NON EXPANSILE EXPANSILE
Air SF6
Nitrogen C4F10
Helium CF4
Oxygen C2F6
Argon C3F8
Xenon C4F10
Krypton C5F12
47. GAS Avg. duration Largest size of
the
bubble(duratio
n)
Average
expansion
Non expansile
concentration
Air 3 days Immediate No expansion --
Sf6 12 days 36 hrs 2 times 18%
C3F8 38 days 72 hrs 4 times 14%
48. Surgical technique
Anaesthesia :
Topical anaesthesia usually with subconjunctival
anesthesia or application of lidocaine soaked pledgets
may be adequate
NO should not be used in case of general anaesthesia
if intraocular gas is to be usesd.
49. STERILIZATION
Sterile lid speculum
Several drops of povidine & iodine .
The injection site is dried with a cotton tipped
applicator & is ready for paracentesis & injection.
50. Preparation of the gas
A 30 guage ,1/2 inch {12 mm} needle is then placed tightly &
excess gas is expelled out, gas should not be kept for more than
few minutes as it can get diluted with the room air.
51. Pure gas is stored in a
cylinder with a regulatory
valve. Two sterile filters
should be connected
between the cylinder and the
syringe in use.
52. As physiological dead
space exists within the
system, accuracy maybe
affected by the air
contained within these
spaces. Pure gas should
then be drawn from
the cylinder and the
syringe flushed a few
times to ensure
complete
evacuation of air from
the dead space.
Appropriate amount of
pure
gas is then drawn into
the syringe.
53. The syringe with one
filter is
then disconnected. The
three-way tap is then
turned to the other
unused filter, and air is
drawn in to achieve the
appropriate
concentration of air–gas
mixture.
54. PARACENTESIS
Performed before injection
Requires:- half inch, 30 guage needle mounted on 1
ml syringe without a plunger.
Site: paracentesis should be performed through the
limbus in phakic patients.
Otherwise it should be done from the pars plana .
60. Introduction
Silicone oil (SO) was first introduced as an internal
tamponade agent in the early 1960s.
Clinical usage of SO in treating retinal detachment
was first introduced by Paul Cibis in the 1960s,
before the introduction of pars plana vitrectomy.
Indications of SO
giant retinal tears, viral retinitis, traumatic retinal
detachments , (PDR), complicated pediatric retinal
detachments, macular hole surgeries, and
endophthalmitis.
61. Physical property of SO
specific gravity: same as that of aqueous(1.00).
BUOYANCY : it is small which makes the SO to take
aspherical shape.
Surface & interfacial tension: interfacial tension
refers to the force that tends to keep a bubble as a
whole It has been found that an oil bubble remains
intact as long as the interfacial tension is above 6
mN/m (milli-Newton/meter).
68. MECHANICS
Peeling:Force along the axis of a collagen fiber
bundle causes non-elastic collagen fibers to slightly
stretch and ultimately to fail. Membrane peeling
requires force perpendicular and tangential to the
retina which causes failure of the attachment at the
vitreoretinal interface by elongation.
69. Fig. 101.2 Forceps designed to place one
blade under the epiretinal
membrane (ERM) damage the retinal
surface. Similarly, pics and
membrane scrapers damage the retinal
surface.
70. SHEAR
Shear cutting occurs when force is applied along two
opposing parallel edges moving past each other.
Vitreous cutters and scissors use shearing to cut
tissue.
71.
72. Fig. 101.3 Scissors create a push-out
force; if they are inserted open
and then closed they tear the retina at the
epiretinal membrane
attachment points
73.
74. FATIGUE FAILURE
Fatigue failure occurs when repetitive motion,
elongation, and compression weaken tissue structure
and cause failure. Ultrasonic cavitation
(fragmentation, phacoemulsification) is an
example of this mode of cutting.
75. An
excessively steep
entry angle creates
a long scleral
tunnel, but
increases the risk
of infusing into the
suprachoroidal or
subretinal space
76. Infusion into the suprachoroidal space
causes expansion of
the peripheral choroid.
77. If the infusion cannula does not extend
into the vitreous
cavity, a 25G MVR blade can be used to
incise the tissue covering
the tip.
78. Infusion through a 25G needle will
compress the choroid
and cause egress of the suprachoroidal
fluid around the cannula.
81. Vitreous cutters
All current vitreous cutters utilize suction and
inclusive shearingi deal tissue cutting is defined as that
producing zero displacement of the tissue to be
removed and no vitreoretinal
traction.
82.
83.
84. SCLEROTOMY
Sclerotomies should be located to avoid
conjunctival
scars, filtering blebs, regions of abnormal
pars plana, and allow the
greatest degree of intraocular access.
85. The 25G vitrectomy systems utilize
transconjunctival
trocars, which eliminate suturing, reduce
surgery times, and increase
patient comfort. Conjunctival displacement
ensures that the
conjunctival wound does not overlay the
scleral wound.
86.
87. PATIENT SELECTION
Patients with wide and bullous RD.
Older patients with presence of RD.
The presence of RD with marked traction with
different anterior posterior depth of breaks.
The presence of breaks in multiple quadrants, or
the
Absence of an apparent retinal break in a
pseudophakic patient,a liquefied vitreous.
88. PRINCIPLES:
Removal of the vitreous gel and preretinal tractional
membrane.
Intraoperative flattening of the detached retina.
Application of retinopexy.
Placement of a tamponade in the vitreous cavity.
89. SURGICAL TECHNIQUES
Primary vitrectomy is commonly performed using a
wide-angle viewing system attached to an operating
microscope.
CREATES THREE PORTS THROUGH PARS PLANA:
Firmly insert the infusion cannula. Irrigation pressure is set
around 20–35 mmHg, depending on the choice of operating
system gauge. Confirm that the infusion cannula is in the vitreous
cavity by examining its position using an exterior light pipe.
90. CORE VITRECTOMY:
The central vitreous is removed.
Detached retina with posterior vitreous
detachment is
shown. Core vitrectomy is performed
91. PERIPHERAL VITRECTOMY
A bubble of perfluorocarbon
liquid (PFCL) has been
injected to displace posterior
subretinal fluid. While holding
down the
detached posterior retina,
peripheral vitreous base is
safely shaved
and the flap of the retinal break
is cut to release the
vitreoretinal
traction.
97. After
peripheral vitreous
base dissection,
more PFCL has
been injected to the
level of peripheral
tear. Subretinal fluid
was first displaced
anteriorly by PFCL,
and then aspirated
through the
peripheral
retinal break.