Transcript Posterior Capsular Rupture & Vitrectomy

Posterior Capsular Rupture
&
Vitrectomy
Farid Karimian M.D 2002
Capsular Anatomy
-Elastic
basement membrane, type IV collagen
-Thickness: • 2-4  at the posterior pole
Thickest: 17-23  near the ant. & post equator
Ant. Capsule  14  thickness increases with age
-Fragile posterior capsule:
- Congenital post lenticonus, posterior polar
cataract
- Posterior subcapsular ( PSC): age- related,
steroid
Signs of Capsule Rupture
• Sudden, abrupt and dramatic posterior
displacement of iris
• Momentary pupillary dilatation
• Nucleus “ fall away” from the phaco tip
• Nucleus dose not follow toward the phaco tip
NOTE: Any time suspected of ruptured posterior
capsule
modify surgical plan on that suspicion
Predisposing Factors for
Capsular Rupture
1- Position of surgeon’s hand
obscuring
visibility
2- Irrigation fluid pooling
3- Torsion of the globe
4- Poor microscope illumination or alignment
5- Poor visibility secondary to pathology:
dense arcus, ptryguim, band keratopathy,
corneal scars, interstitial keratitis
Predisposing Factors…cont.(1)
Long and short axial length eyes
deep or shallow AC
 Pseudoexfoliation, weak zonules,
poor dilation
 Brunescent or black cataract
 Dense asteroid hyalosis

Predisposing Factors… cont.(2)
Posterior polar cataracts (esp. calcified):
- cataract to post capsule adhesion,
- posterior capsule thining
 Inexperienced surgeons
 Poor visualization (eg. Microscope
problems)

Predisposing Factors… cont.(3)
Demented, disoriented, anxious, and
addict patients: inadvertant movement
 Equipment malfunction
 Pre-existing trauma
unseen
capsular or zonular damage
 Small pupils

When the Posterior Capsule
is Torn?
Terminal stages of phaco for
emulsification of last pieces of
endonucleus
 During posterior capsule polishing
 During I/A
 Hydrodissection, IOL insertion: less
common
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Developing a Surgical Plan
Posterior capsule tear suspicion 
Alternate surgical plan

Goal to minimize prolonged or damaging
Procedures damaging retina and/or cornea
Planning
 Timing (when in the procedure)
 Location (where in posterior capsule)
 Size (small, medium, large, or extra large)
Posterior Capsular Rupture
During Nucleus Emulsification
Two main questions:
1. Is vitreous present in A/C?
2. Is Conversion to ECCE indicated?
Conversion decision:
1. Hardness and size of nucleus
2. Size of pupil
3. Maintain adequate deep A/C
4. Ease of access to anterior segment
5. Level of surgical experience
Conversion to ECCE

Support the lens nucleus with a dispersive
viscoelastic (injection underneath)
 Extend peritomy and corneoscleral
incision
 Open the wound larger than expected
 Use lens loop or manipulator
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No limbal pressure  vitreous will be
expelled
Continued
Phacoemulsification
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Inject viscoelastic below fragment
Protect the endothelium
Lower bottle height, vacuum and flow
Emulsify the nucleus in A/C in one piece
Use second instrument to feed phaco tip
Do not create multiple fragments
The Pseudo-posterior Capsule:
Sheet’s glide after viscoelastic
injection under nucleus
Support nucleus fragments
 Prevent excess loss of vitreous
 Both ECCE and phaco can be done
over Sheet’s glide
 Finally I/A and vitrectomy over glide

Principles of managing an open
posterior capsule
1- Do not mix cataract with vitreous
- Mixture of lens material will cause inflammation
- Isolated cortex in the eye is absorbed with low
reaction
- Cortex- vitreous mixture  variable course 
from tolerance to severe inflammation
Principles of managing an
open posterior capsule…(cont)
- Nucleus left in the eye  variable clinical
outcome
- Small nucleus fragment in A/C  inferior angle
 endothelium rubbing  cell loss

Should be removed
1- Do not mix… cont.
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Nucleus fragments behind iris and above
anterior capsule  fairly harmless
 Nucleus fragments in vitreous 
significant inflammation
 Increased inflammation:
- personal Physiology and response,
- Central nucleus > peripheral chips
 About 1/3 of cases with dropped nucleus
chips develop uveitis and glaucoma
2- Do not stretch the slinky
has natural elasticity  extending down to
macula (not necessarily)
-Tensions on anterior vitreous  exertion through
entire vitreous body  pulling on the macula and
vitreous base
During phacoemulsification  small incisions plugged
by instruments 
If pressure A/C is kept sufficient Prevent vitreous
prolapse

Forces remained in anterior vitreous

No transmission to macula or vitreous base
-Vitreous
Posterior Assisted Levitation
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When stabilization of nucleus is impossible
Distal zonular dehiscence  Distal pole of
nucleus falling into the vitreous
Pars plana stab incision 3.5mm posterior to
limbus
Site of incision  wherever zonular hinge
occurs
Cyclodialysis spatula  lever the nucleus
into the A/C
Removal by phaco or extracapsular
approach (preferred)
Specific Clinical Situations
Posterior capsule rupture and vitreous loss
situations
1- During Capsulotomy and
Hydrodissection
-poorly directed anterior capsule  peripheral
extension

Tear usually stops by zonule network
High volume with rapid injection  extends radial
tear into equator and back to posterior capsule
Specific Clinical Situations
cont…
Small capsulorrhexis  phaco needle
trauma
 Sharp hydrodissection needle  radial tear
formation
 Presence of posterior polar cataract or post
capsule defect
 High MW viscoelastic injection under capsular
 wound extension  nucleus delivery

2- During Sculpting
• Hard nucleus  insufficient power- blunt needle tip
- low machine power settings
- low power generation
• Nudging nucleus toward 6 o’clock  pushing
inferior capsule
Pulling on superior zonules
• Superior zonular dehiscence  whole
nucleus moved down
Failure of nucleus to return
• Conversion into ECCE after anterior capsule relaxing
incisions
2- During Sculpting…cont.
Peripheral sculpting  capsular trauma
 High vacuum sculpting  sudden
emulsification of posterior nuclear
plate and cortex  capsular rupture
 Inferior capsulorrhexis rim trauma 
posterior extension
 Improper focusing on sculpting depth
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3- During Rotation of the Nucleus
Causes: - inadequate hydrodissection (nucleus
adhered to capsule)  shearing off zonules
- Second instrument- capsule trauma
- Unstable zonules e.g. pseudexfoliation
 bimanual rotation
• If shearing of zonules is complete  ICCE
removal must be done
• Zonular dehiscence
- <90°  complete hydrodissection  PE
- 90°- 270°  capsular tension ring  PE
- >270°  ECCE with radial tears in anterior
capsule or ICCE
4- During Emulsification
Causes
:
- Small capsulorrhexis and during division
- Sudden flattened A/C and capsular bag
- Uncontrolled surge during emulsification
nucleus particle
- Sharp ends of nuclear fragments
Management
:
- Protection of remaining PC with viscoelastic
- Sheet’s glide support of nucleus fragmentpushing back PC and vitreous
- Emulsification of nucleus fragments over glide
in A/C
5- During Cortical Aspiration
Causes
:
Post capsule trauma by I&A tip: Flat AC, excess
aspiration
• Anterior capsule entrapment in aspiration port 
traction
• Inadequate hydrodissection
•
Management:
- Place dispersive viscoelastic over the vent
- Embed I&A tip into the cortex  apply vacuum
(not aspirating vitreous)
- Stripping toward capsule tear
- Lower infusion bottle  inflow,  turbulence
- Vitrectomy tip can be used for cortical removal
- Leave cortical material: if not too much!
6- During or After IOL Implantation
More complicated than earlier phases
 First: secure IOL to prevent sinking
 Use viscoelastic to hold vitreous back
 By clockwise rotation bring IOL into
sulcus or AC
 If capsulorrhexis is intact  sulcus
fixation

During or After IOL
Implantation… cont.(1)
Close the wound  to prevent flat AC,
further endothelial damage
 Bimanual vitrectomy over and under
the IOL
 Constrict pupil by intraocular miotic
injection over IOL  check vitreous
clearance
 If no sufficient capsular support 
transscleral fixation, or ACIOL
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Vitrectomy Following Vitreous Loss:
Principles
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Keep AC as closed as possible: instruments,
suture
Maintain IOP stable: keep foot pedal at stage
I, use viscoelastics
Loss of anterior segment  forward
displacement of vitreous
Vitrectomy setting: suction 60mmHg, cut:
360-400 cpm
Do vitrectomy adequately
Keep capsule rent as small as possible
Vitrectomy with Coaxial Infusion
- Special tip to-reduce no. of entrances
- Easily placed through phaco incision
- It fails, because stretches the slinky
1. The coaxial infusion strikes posterior capsule 
 rupture size
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More vitreous comes forward
2. Coaxial cannula reaching the body of vitreous 
hydration of vitreous
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Increase vitreous volume
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 Forward movement
3. Flow moves the vitreous around  wiggling and
shaking vitreous  flush it forward
Recommendation:
cannula
Don’t use coaxial infusion
Two-handed (port) Vitrectomy
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Close the entrance wounds for vitrectomy tip
 i.e. make a closed system
Procedure will be performed rapidly and
conveniently
Perform small vitrectomy without irrigation
Prevent eye softening by repeated injection
of viscoelastic  push vitreous back
Chamber-maintainer through side-port forms
AC
Remove the vitreous to below the level of
posterior capsule
Postoperative Care
At conclusion of surgery:
- Betamethasone 4mg (short-acting)
- Antibiotic e.g. Gentamicin 20mg
- Trimcinolone (kenalog) 20mg or Methylprednisolone 40mg (longer anti-inflammatory
action)
- Take care of IOP rise, endophthalmitis, and
other complications of vitreous loss
- Systemic steroid, prednisolone 1-1.5 mg/kg
PO for 7-14 days