Posterior Capsular RupturePosterior Capsular Rupture

& &

Vitrectomy Vitrectomy

Farid Karimian M.D 2002Farid Karimian M.D 2002

Capsular Anatomy 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 RuptureSigns 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 Predisposing Factors for Capsular RuptureCapsular 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)Predisposing Factors…cont.(1)

Long and short axial length eyes deep or shallow AC

Pseudoexfoliation, weak zonules, poor dilation

Brunescent or black cataractDense asteroid hyalosis

Predisposing Factors… cont.(2)Predisposing Factors… cont.(2)

Posterior polar cataracts (esp. calcified):

- cataract to post capsule adhesion,

- posterior capsule thiningInexperienced surgeonsPoor visualization (eg. Microscope

problems)

Predisposing Factors… cont.(3)Predisposing Factors… cont.(3)

Demented, disoriented, anxious, and addict patients: inadvertant movement

Equipment malfunctionPre-existing trauma unseen

capsular or zonular damageSmall pupils

When the Posterior Capsule When the Posterior Capsule is Torn?is Torn?

Terminal stages of phaco for emulsification of last pieces of endonucleus

During posterior capsule polishingDuring I/AHydrodissection, IOL insertion: less

common

Developing a Surgical PlanDeveloping 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 Posterior Capsular Rupture During Nucleus EmulsificationDuring 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 ECCEConversion 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

No limbal pressure vitreous will be

expelled

Continued Continued PhacoemulsificationPhacoemulsification

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:The Pseudo-posterior Capsule: Sheet’s glide after viscoelastic Sheet’s glide after viscoelastic

injection under nucleusinjection 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 Principles of managing an open posterior capsuleposterior 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 Principles of managing an open posterior capsule…(cont)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.1- Do not mix… cont.

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 slinky2- Do not stretch the slinky-Vitreous 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

Posterior Assisted LevitationPosterior Assisted Levitation

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 SituationsSpecific Clinical SituationsPosterior 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 Specific Clinical Situations cont…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 Sculpting2- 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.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

3- During Rotation of the Nucleus3- 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 Emulsification4- During EmulsificationCauses:

- 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 fragment- pushing back PC and vitreous - Emulsification of nucleus fragments over glide in A/C

5- During Cortical Aspiration5- During Cortical AspirationCauses:

• 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 Implantation6- 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 During or After IOL Implantation… cont.(1)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

Vitrectomy Following Vitreous Loss: Vitrectomy Following Vitreous Loss: PrinciplesPrinciples

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 InfusionVitrectomy with Coaxial Infusion- Special tip to-reduce no. of entrances- Easily placed through phaco incision - It fails, because stretches the slinky1. The coaxial infusion strikes posterior capsule rupture sizeMore vitreous comes forward2. Coaxial cannula reaching the body of vitreous

hydration of vitreousIncrease vitreous volume Forward movement3. Flow moves the vitreous around wiggling and

shaking vitreous flush it forward

Recommendation: Don’t use coaxial infusion cannula

Two-handed (port) VitrectomyTwo-handed (port) Vitrectomy

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 CarePostoperative Care At conclusion of surgery: - Betamethasone 4mg (short-acting)- Antibiotic e.g. Gentamicin 20mg- Trimcinolone (kenalog) 20mg or Methyl- prednisolone 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