indications,contraindications,types,advantages,procedure of cyclocryo,when to do it cyclocryo, easy to understand

1. CYCLODESTRUCTIVE
PROCEDURES
DR.ARINO JOHN
MS OPHTHALMOLOGY

2. CYCLODESTRUCTIVE
PROCEDURES

3. INTRODUCTION
 Decrease IOP by destroying the ciliary processes and
non pigmented ciliary body epithelium which produces
the aqueous fluid.
Last line management and a reserved procedure.
 Because the ciliary epithelium can regenerate,
multiple treatments are necessary in some patients to
achieve the desired long term IOP lowering effect.

4. INDICATIONS
 Refractory ocular pain in absolute glaucoma.
Uncontrolled IOP despite max medicat t/t.
Multiple failed filtrations or shunt surgery.
Cases with severly scarred conjunctiva and
poor visual prognosis.
NVG

5. Aphakia and pseudophakic glaucoma
Glaucoma following PK
Traumatic glaucoma
Post uveitic glaucoma
Congenital glaucoma (failed t/t)
INDICATIONS

6. CONTRAINDICATIONS
1. Thin sclera
2. Limbal deformation
3. Scleritis
4. Phakic eyes with good vision.

7. TYPES OF CYCLODESTRUCTIVE
PROCEDURES
Cyclocryotherapy
Laser cycloablations
Cycloelectrolysis
Diathermy
Beta irradiations
Therapeuctic ultrasound.

8. CYCLOCRYOTHERAPY
 Ideal for a painful blind eye.
Destroys the ciliary epithelium with a
cryoprobe through intact conjunctiva and
sclera.
Good pain relief and success rates
But high complication rate.

9. EFFECTS OF CRYOTHERAPY
•Ischemia caused by
vascular stasis and
the destruction of small caliber blood vessels
•Ice crystal formation inside cells leading to cell wall rupture
•Denaturing of lipid- protein complexes
•Osmotic stress
•Tissue necrosis
•Cellular apoptosis after freezing injury by the buildup of toxic
concentrations of solutes inside cells

10. September 09, 2015 Department of Ophthalmology, JNMC, Belagavi 7
Thus,
concentrating
the remaining
extracellular
solutes
As Cryotherapy freezes extracellular fluid, pure water
crystals form extracellularly
The intracellular water is cooling below
its freezing point but not forming ice
crystals
Known as
Supercooling
Cell membrane is
permeable to
supercooled water
So the supercooled water will tend to
flow out of the cell and freeze externally
The net result is-
• Cellular dehydration
• Solute concentration intracellularly

11. PROCEDURE
•Under peribulbar/retrobulbar anesthesia
•A cryoprobe of 2.5mm is used.
• Cryoconsole
•Tank of gas (cryogen)
•Foot pedal

12. •A circular and convex retinal cryoprobe (3mm or 4mm
tip) is applied directly on the intact conjunctival
surface.
•The edge of the tip is placed 1-1.5mm from the limbus
for 1 minute, thus bringing the center of tip directly
over cilliary body
•Cryotip temp at -80 degree Celsius.
•180 degree is treated at one session.
•The ice-ball is allowed to thaw slowly, rather than
using irrigation, to allow maximal effect.

13.  For adequate cellular destruction, the thaw phase of cryotherapy is
just as crucial.
 A slow thaw allows for longer vascular stasis and longer exposure to
toxic solute levels within the cell
 The effect is enhanced by repeated freeze-thaw cycles, usually
performed 2-3 times
known as “DOUBLE FREEZE THAW TECHNIQUE”
September 09, 2015 Department of Ophthalmology, JNMC, Belagavi 8
THAW PHASE

16. VARIOUS CRYOGENS
• Freon (boiling point = −29.8 ̊Cto −40.8 ̊C)
• Nitrous oxide (boiling point = −88.5 ̊C)
• Solid carbon dioxide (melting point = −79 C̊ )
• Liquid nitrogen (boiling point = −195.6 C̊ )
Boiling point of liquid nitrogen is by far the lowest,
making it the most effective in cell destruction.

17. POSTOPERATI
VE CARE
COMPLICATIO
NS

18. CYCLOABALTION
Procedure by which laser energy is used to destroy te
cilry epithelium,stroma and vascular supply.
Types
 Transcleral cyclophotocoagulation
contact & non-contact method.
Transpupillary endolaser
Endoscopic endolaser

19. LASERS USED IN CYCLOABLATION
DIODE
LASER
(810nm)
Nd:YAG
(1064nm)
DIODE
LASER
(SOLID
STATE)
KRYPTON
LASER

20. TRANSCLERAL
NON-CONTACT METHOD:
 Under retrobulbar anesthesia.
Using slit lamp
Site : 1-1.5mm posterior to limbus
( avoid 3 and 9’0clock meridians)
Energy – 4 to 8 joules for 20 ms.
Special contact lens can be used.
Success rate : 50% to 86 %

21. CONTACT METHOD
 Nd:YAG/Diode laser is used
Continuous laser beam .
G-probe used
0.5mm to 1mm posterior to limbus.
“POP”sound
TRANSCLERAL
Nd:YAG Diode
0.7 W 1.5-2 W
0.7S 2.5S

22. ADVANTAGES DISADVANTAGES
SIMPLE PROCEDURE VISUAL LOSS
EASY FOLLOW UP POSTOP PAIN & INFLAMMATION
LOW COST TRANSIENT IOP RISE
GOOD SUCCESS RATES PTHISIS BULBII

23. COMPLICATIONS
Severe pain
Hypotony and
phthisis bulbii
Visua loss
Severe inflammation
Acute rise in IOP
Scleral thinning
Vitreous
haemorrhage
Hyphaema
Vitritis
Aqueous
misdirection
Sympathetic
ophthalmitis
Corneal
decompression
Retinal detachment
Cataract in phakic
patients.