for UG level

1. POAG – Surgical management
Vinaykumar .S. Appannavar
Roll no: 90

2.  Argon laser (ALT)
 Diode laser (DLT)
 Selective laser (SLT)
 It is done in patients where IOP is uncontrolled despite maximal
tolerated medical therapy
 Where there is non-compliance to medical therapy it can be used
Laser trabeculoplasty

3. Technique and role of (ALT) or (DLT)
 Its hypotensive effect is caused by the producing collagen shrinkage on
inner aspect of trabecular meshwork and opening the inter trabecular
spaces
 Its been shown to lower
IOP by 8-10 mm of hg in patients – on medical therapy
IOP by 12-16 mm of hg in patients – not on medical therapy
 it consists of 50 spots on the anterior half of trabecular meshwork over
180 deg.
Treatment regime

4. Transient acute rise of IOP , which can be prevented by
pretreatment with apraclonidine and/or acetazolamide
Transient inflammation which can be lessened by use of
topical steroids for 3-4 days
Other complications seen less commonly are
haemorrahage , uveitis, peripheral anterior synechiae and
reduced accommodation
Complications

5. ( Selective laser trabeculoplasty)
 It targets selectively pigmented trabecular meshwork cells without
causing collateral damage to non-pigmented cells or stuctures unlike
ALT or DLT.
SLT

6. ND:YAG Laser
• Pressure lowering effect of SLT is similar to ALT with the
advantage of not causing damage and scarring to TM
• Further, it can be used in patients treated with ALT
SLT is performed
using Q- switched
frequency doubled
532nm ND:YAG laser
with a pulse duration
of 3 ms a spot size of
400 microns and
0.8mJ energy

7. Indications :
 Uncontrolled glaucoma despite of maximal medical therapy & laser
trabeculoplasty
 Noncompliance of medical therapy & non availability of ALT/ SLT
 Failure of medical therapy & unsuitable for ALT/SLT
 Eyes with advanced disease , i.e., having very high IOP, advanced
cupping & advanced field loss
Types :
 It primarly consists of a fistulizing surgery
o Trabeculectomy .
o Filtration operations
Surgical therapy

8. Filtering operations
It provide a new channel for aqueous outflow and successfully
control IOP ( below 20 mm of Hg )
External filtration surgery Internal filtration surgery
1.Free-filtering operations 1.Cananoplasty
2.Gaurded filtering surgery 2.Trabectome
( trabeculectomy ) 3.iStent
3.non-penetrating filtration surgery
( deep sclerectomy & viscocanalostomy )

9. Trabeculectomy
Indications :
 Primary open-angle glaucoma
 Primary angle-closure glaucoma with anterior synechial involving
more than 270 deg. angle or where PI and medical treatment fail
 Congenital and developmental glaucomas
 Secondary glaucomas
Mechanisms of filtration :
 A new channel is created around the margin of scleral flap through
which aqueous flow from anterior chamber subconjuctival space
 If the tissue is dissected posterior to scleral spur, a cyclodialysis may
be produced leading to increased uveoscleral outflow
 Aqueous flows through the cut ends of Schlemm’s canal, now it is
established that this mechanism has negligible role

10. Surgical technique
 Initial steps of anaesthesia, cleansing,
draping ,exposure of eyeball and fixation
with superior rectus suture
 Conjunctival flap , a fornix based conjunctival
flap is fashioned and the underlying sclera is
exposed.
 Scleral flap , a partial thickness limbal based
scleral flap of 5mm*5mm size is reflected down towards the cornea
 Excision of trabecular tissue, a narrow strip of the exposed deeper
sclera near the cornea containing the Schlemmn canal and
trabecular meshwork
 Peripheral iridectomy

11.  Closure, the scleral flap is replaced and 10-0 nylon sutures are
applied then the conjunctival flap is reposited with or continuous
suture
 Subconjunctival injections of dexmethasone and gentamycin are
given
 Patching

12. Complications
 Postoperative shallow anterior chamber, hyphaema, iritis, cataract
due to accidental injury to the lens and endopthalmitis
Use of antimetabolites
Any of the following risk factors for the failure of conventional
trabeculectomy are present
 Previous failed filtration surgery
 Glaucoma in aphakia
 Secondary glaucomas
 Patients treated with topical antiglaucoma medications
 Chronic cicatrizing conjunctival inflammation

13. Antimetabolite agents
 Either 5- fluorouracil or mitomycin -C can be used
 A sponge soaked in 0.02% solution of mitomycin –C is placed at the
site of filtration b/w the scleral and Tenon’s capsule of two minutes,
followed by a thorough irrigation with balanced salt solution
 Use of collagen implant with glaucoma filtration surgery
 Technique: Usually a 6mm diameter and 1mm thick implant is
sutured over the scleral flap.

14. Deep sclerectomy
Viscocanalostomy
Non-penetrating filtration surgeries

15. Canaloplasty
Trabectome
Internal filteration
surgeries

16. iStent : is a titanium
microdevice that is place inside
the Schlemm’s canal