DR. KOUSHIK TRIPATHY

koushiktripathy@gmail.com

drkoushik.blogspot.com

TRABECULECTOMY

HISTORY

• FULL THICKNESS FISTULA / FREE FILTERING SURGERY

• SCHIE’S THERMAL SCLEROSTOMY

• ELLIOT’S SCLEROCORNEAL TREPHINING

• IRIDENCLISIS

• PUNCH SCLERECTOMY

• ABANDONED NOW- FLAT AC, CORNEAL DECOMPENSATION, SYNECHIAE,THIN BLEBS RUPTURE- ENDOPHTHALMITIS

EVOLUTION• CAIRNS INTRODUCED IN 1968

• AIM TO EXCISE A BLOCK OF SCHLEMM’S CANAL AND TRABECULUM (TRABECULECTOMY) TO ALLOW DRAINAGE INTO EXPOSED END OF SCHLEMM’S CANAL & NOT FOR CREATING FISTULA TO RESULT IN DRAINAGE BLEB

• DRAINAGE BLEB WAS CONSIDERED FAILURE OF SURGERY

• DRAINAGE BLEB SUBSEQUENTLY FOUND TO BE A/W INCREASED SUCCESS RATE

• GUARDED FILTRATION ( PARTIAL THICKNESS FISTULA) SURGERY

• DRAINAGE GUARDED BY SCLERAL FLAP

POSSIBLE MECHANISMS OF ACTION

• FILTRATION AROUND MARGINS OF SCLERAL FLAP

• FILTRATION THROUGH CONNECTIVE TISSUE SUBSTANCE OF SCLERAL FLAP

• THROUGH OUTLET CHANNELS OF SCLERAL FLAP

• CYCLODIALYSIS IF TISSUE IS DISSECTED POSTERIOR TO SCLERAL SPUR INCREASED UVEOSCLERAL OUTFLOW

• AQUEOUS FLOW THROUGH CUT ENDS OF SCHLEMM’S CANAL( RARE)

INDICATION

• FAILED MEDICAL THERAPY &/OR LASER TRABECULOPLASTY/ PI

• INTOLERANCE /NONCOMPLIANCE TO MEDICAL THERAPY

• UNSUITABILITY OF ALT/PI – POOR PT COOPERATION, INADEQUATE VISUALISATION OF TRABECULUM

• ADVANCED VISUAL FIELD DEFECT AT PRESENTATION

• RAPIDLY PROGRESSIVE VISUAL FIELD LOSS

• ADVANCED GLAUCOMA/NTG NEEDING LOW IOP (10-15mm Hg)

• MAY BE 1ST LINE FOR ‘DROP FREE’ LIFE

PREOP ASSESSMENT• IOP & NAME OF ANTIGLAUCOMA MEDICATIONS

• UP TO DATE VISUAL FIELD

• DISC CHANGES

• CONTROL OF SYSTEMIC DISEASES/ CLEARANCE

• STOP ANTICOAGULANTS

• AVASTIN (NVG)

• T. ACETAZOLAMIDE (10 mg /kg)

• IV MANNITOL ON DAY OF SURGERY (1g/kg)

• TOPICAL ANTIBIOTIC EYE DROP QID B/E × 3 DAYS PRIOR TO SURGERY

• STOP PG ANALOGUES

• NO MYDRIATIC

CONSENT

• SURGERY TO PRESERVE VISION, NOT TO IMPROVE IT

• FAILURE

• INFECTION – ENDOPHTHALMITIS, BLEBITIS

• BLEED- SUPRACHOROIDAL

• FURTHER SURGICAL PROCEDURES

• NEED FOR MEDICATION

• BLINDNESS

• CATARACT

• POSSIBLE CHANGE IN SPECTACLE POWER

ISSUE

ANAESTHESIA• PERIBULBAR – • MOST COMMONLY USED

• INCREASES IOP

• REDUCED OCULAR BLOOD FLOW- POTENTIALLY BLINDING FOR END STAGE GLAUCOMA

• REDUCE VOL OF BLOCK WITH HYALASE

• AVOID PINKY

• CHANCES OF PERFORATION MORE IN MYOPE, BUPHTHALMOS, POSTERIOR STAPHYLOMA

• TRANSIENT ENLARGEMENT OF SCOTOMA

• INCREASED TENSION OF CONJUNCTIVA & TENON POSTERIOR TISSUE RETRACTION, DIFFICULT WOUND CLOSURE

• MAY INCREASE POST OP BLEB FIBROSIS

SURGICAL TECHNIQUE -

• PARTS CLEANED AND DRAPED

• COENEAL TRACTION SUTURE -6-0

• FORNIX / LIMBAL BASED CONJUNCTIVAL FLAP >10mm incision SUPERIOR LIMBUS

• SUBCONJUNCTIVAL SPACE DISSECTED- SUBTENON POCKET 15*15mm

• SCLERAL AREA CAUTERISED

• SUBCONJUNCTIVAL 0.02% MMC FOR 3 MIN

• PARTIAL THICKNESS(TRAPDOOR LAMELLAR) SCLERAL FLAP 4mm* 3mm

• SUPERFICIAL FLAP DISSECTED FORWARD UNTIL CLEAR CORNEA

• TRABECULECTOMY USING PUNCH

SURGICAL TECHNIQUE

• PARACENTESIS AT TEMPORAL CORNEA

• AC FORMED WITH AIR

• MVR ENTRY

• PI

• SCLERAL FLAP SUTURED

• RELEASABLE APPLIED

• PATENCY OF FISTULA CHECKED BY BSS THROUGH PARACENTESIS

• PERITOMY CLOSED

• SUBCONJ GENTA AND DEXA

• PAD AND BANDAGE

TRACTION SUTURE

• SUPERIOR RECTUS BRIDLE SUTURE-

• 1>CAUSE SUBCONJ HGE/ SUP. RECTUS HAEMATOMA RELEASE OF GROWTH FACTORS TRIGGERS HEALING FAILED TRAB

• 2>GLOBE PERFORATION

• 3>RETROBULBAR HGE

• 4>PTOSIS

• 5> PAIN , DISCOMFORT

• 6> CONJUNCTIVAL DAMAGE (hole)

• CORNEAL TRACTION SUTURE (CONKLIN et al ’1991)

• CORNEAL DEPTH OF APPROXIMATELY THREE-FOURTHS THICKNESS, 1 MM FROM THE LIMBUS WITH A BITE WIDTH OF 4 TO 5 MM

• NO BLEED , CONJ DAMAGE

• VECTOR FORCE MORE THAN SR BRIDLE

• RISK OF PASSING TOO SUPERFICIALLY (CHEESE-WIRING) / TOO DEEP –AC ENTRY ESP IN MYOPIA / BUPHTHALMOS

• FBCF

• Easier and faster surgical time

• Good exposure allows good visualization of sclerostomy and easier placement of “releasable” sutures

• Smaller Area to be dissected

• Antifibrotic application Need great care on insertion, may need more sponges

• Re-operation Easier

• LBCF

• More difficult and longer surgical time

• Exposure more difficult to obtain with less visualization of sclerostomy. Usually need assistant. Reflected conjunctiva may make releasable suture placement difficult

• Larger Area to be dissected

• Easier antifibrotic application

• More difficult due to extensive scarring

FORNIX BASED V/S LIMBAL BASED CONJUNCTIVAL FLAP

• FBCF

• Bleb morphology More diffuse in shape and drain more posteriorly

• Conjunctival wound

• leakage

• May have higher incidence of early Conjunctival wound leaks, but published results are variable. Almost eliminated with corneal conjunctival closure technique

• LBCF

• May get cystic blebs and “ring of steel” (posterior limiting scar ) with drainage limited to anterior area

• May have less early wound leaks

FORNIX BASED V/S LIMBAL BASED CONJUNCTIVAL FLAP CONTD..

The inferior quadrant -1> in the past when previous ocular surgery resulted in scarring of conjunctiva in the superior quadrants increased risk of endophthalmitis and should be avoided .2> SILICONE OIL INDUCED GLAUCOMA

FBCF LBCF

SCLERAL FLAP

INTRAOP ANTIFIBROTIC AGENTS

• TISSUE HEALING MAY BE MODULATED WITH ANTIMETABOLITES TO IMPROVE OUTCOMES OF TRABECULECTOMY.

• 5-FU OR MMC IS RECOMMENDED FOR ALMOST ALL TRABECULECTOMIES

• 4–6 SPONGES WITH MITOMICIN C (0.2 OR 0.5 MG/ML) OR 5FU(50 MG/ML)

• MEDICAL GRADE POLYVINYL ALCOHOL(PVA) SPONGES PREFERRD (DO NOT FRAGMENT LIKE METHYL CELLULOSE SPONGE LESS MICRODEBRIS LESS FOREIGN BODY GRANULOMA

• COVER LARGEST AREA POSSIBLE DIFFUSE NONCYSTIC BLEB, PREVENTS ‘RING OF STEEL’

• AVOID CONJUNCTIVAL WOUND EDGES

• AFTER 3 MINUTES REMOVE SPONGES –UPTAKE OF ANTIMETABOLITE IS EXPONENTIAL UNTIL 3 MIN, SUGGESTING THAT THE DOSE RATHER THAN THE DURATION OF CONTACT SHOULD BE VARIED

• IRRIGATE WITH 20 ML OF BALANCED SALINE SOLUTION

ANTIFIBROTICS

• 5-FLUOROURACIL

• ANTIMETABOLITE

• PYRIMIDINE ANALOGUE ANTIMETABOLITE, BLOCKS DNA SYNTHESIS THROUGH THE INHIBITION OF THYMIDYLATE SYNTHESIS

• 50 MG/ML INTRAOP

• SUB CONJ 0.1 ML -BELIEVED TO BE MOST EFFECTIVE IF STARTED PROPHYLACTICALLY ON THE FIRST POSTOPERATIVE DAY, ALTHOUGH SUCCESS HAS BEEN REPORTED WITH STARTING 3 TO 15 DAYS POSTOPERATIVELY WHEN SIGNS OF IMPENDING BLEB FAILURE ARE NOTED

•

ANTIFIBROTICS• MITOMYCIN-C

• ANTINEOPLASTIC ANTIBIOTIC ISOLATED FROM STREPTOMYCES CAESPITOSUS

• 5-FU TOXIC TO CULTURED MOUSE FIBROBLASTS WHILE SPARING BOVINE VASCULAR ENDOTHELIAL CELLS

• MMC CYTOTOXIC FOR BOTH CELL TYPES

• MITOMYCIN C IS A POTENT DNA CROSSLINKER REDUCTIVE ACTIVATION FOLLOWED BY TWO N-ALKYLATIONS

• COMPLICATIONS

• 5 FU -CORNEAL EPITHELIAL TOXICITY AND WOUND LEAKS

• MITOMYCIN-C - HYPOTONY MACULOPATHY ( 1 > EXCESSIVE FILTRATION, 2> AQUEOUS HYPOSECRETION,DISRUPTION OF THE CILIARY BODY EPITHELIUM BENEATH THE SITE OF MMC APPLICATION ), BLEBITIS 5% PER YR, ENDOPH 1% PER YR

• BOTH – CYSTIC THIN WALLED BLEB – PREDISPOSES TO CHRONIC HYPOTONY, LATE ONSET BLEB LEAK, ENDOPH

MITOMYCIN-SOAKED SPONGE BEING INSERTED

POST OP ADVICE• OPEN PAD AND BANDAGE AFTER 6 HRS

• EYE DROP BETNESOL N (betamethasone sodium phosphate 0.1 % w/v, neomycin sulphate 0.5 % w/v) 2 HOURLY

• E/O NEOSPORIN H (hydrocortisone 10 mg/1 g, neomycin sulphate 3400 u, polymyxin B sulphate 5000 u, zinc bacitracin 400 u) HS

• E/D TROPICAMIDE 1% EVERY 5 MIN FROM 7AM TO 8AM

THEN TDS

COMPLICATIONS

• INTRAOP-• CONJUNCTIVAL TEAR

• SCLERAL FLAP DAMAGE

• IRIDODIALYSIS

• BLEED- CONJUNCTIVAL, SCLERAL , IRIS

• SUPRACHOROIDAL HGE

• DECOMPRESSION RETINOPATHY- RETINAL HE

• VITREOUS HGE

• VITREOUS LOSS

POST OPCOMPLICATIONS

• SHALLOW AC –

• 1> PUPIL BLOCK -

FLAT BLEB, SEIDEL –VE, NON PATENT PI WITH OCCLUDED PUPIL MARGIN, HIGH IOP, IRIS BOMBE

Nd YAG PI

• 2> OVER FILTRATION-

INADEQUATE CLOSURE OF CONJ & TENON – MC CAUSE

SCLERAL FLAP LEAK – SEIDEL –VE, FORMED BLEB

BLEB LEAK – SIEDEL +VE, FLAT BLEB

OVER FILTRATION CONTD…

• MANAGEMENT—

• INITIAL – ATROPINE, TOPICAL BETA BLOCKER OR ORAL DIAMOX, MANNITOL

• SUBSEQUENT – TAMPONADE

PRESSURE PATCHING

LARGE DIAMETER SOFT BCL

COLLAGEN SHIELD

SIMMONS SHELL

• DEFINITIVE – LENTICULOCORNEAL TOUCH-AC REFORMATION WITH

AIR , HEALON GV, SF6

VERY DEEP AND KISSING CHOROIDALS -DRAINAGE OF

CHOROIDAL DETACHMENTS

RESUTURE SCLERAL FLAP & CONJ

MALIGNANT(CILIARY BLOCK) GLAUCOMA• aqueous MISDIRECTION BY ANT HYALOID FACE

• HIGH IOP

• MANAGEMENT-

• INITIAL- MYDRIATICS ATROPINE 1% AND PHENYLEPHRINE 10%

MANNITOL

• SUBSEQUENT -

PHAKIC- Nd YAG THROUGH PI TO REMOVE PERIPHERAL ANT

HYALOID FACE

PSEUDOPHAKIC – Nd YAG THROUGH PI TO REMOVE ANY CORICAL

REMNANTS, CAPSULE, PERIPHERAL ANT HYALOID

FACE

CATARACTOUS- LIMITED CORE VITRECTOMY

PHACOEMULSIFICATIONRESIDUAL VITRECTOMY (VPV)

FAILURE OF FILTRATION

• FUNCTIONING FILTERING BLEB-

AVASCULAR

EITHER DIFFUSE AND LOW

OR MORE CIRCUMSCRIBED AND ELEVATED

LOOSELY ARRANGED TISSUE <FIBROCYTES> WITH HISTOLOGICALLY CLEAR SPACES

NUMEROUS MICROCYSTS IN EPITHELIUM

• POOR FILTRATION-

• 1> VASCULARISED BLEB WITH EPISCLERAL FIBROSIS

• 2> ENCAPSULATED BLEB ( TENON CYST)

CAUSES OF BLEB FAILURE • EXTRA OCULAR- SUB CONJ & EPISCLERAL FIBROSIS

BLEB ENCAPSULATION

• SCLERAL – OVER TIGHT SCLERAL FLAP SUTURE

SCARRING OF SCLERAL BED

• INTRAOCULAR – BLOCKED SCLEROSTOMAY BY VITREOUS. BLOOD, UVEAL

ISSUE

BLOCKED INTERNAL OPENING

MANAGEMENT OF BLEB FAILURE• OCULAR COMPRESSION – DIGITAL COMPRESSION

AT SLIT LAMP WITH MOISTENED STERILE

COTTON BUD PRESSURE AT POST LIP OF FLAP

CHECK IOP AFTER 30 MIN

• SUTURE MANIPULATION- AFTER 1 – 2 WK IF IOP NOT CONTROLLED, FLAT

BLEB, DEEP AC

???RELEASABLE SUTURE CUT OR RELEASED

ARGON LASER SUTURE LYSIS

• NEEDLING WITH / WITHOUT 5 FU UNDER TOPICAL

• SUBCONJ 5 FU 5mg – 10MM AWAY FROM BLEB IN 1ST 7-14 DAYS

LATE BLEB LEAKAGE

• DUE TO DISSOLUTION OF CONJ FOLLOWING INTRAOP ANTIFIBROTIC PARTICULARLY MMC

• LOW IOP

• AVASCULAR CYSTIC BLEB

• SEIDEL – EARLY >>> NEGATIVE ,MULTIPLE PUNCTATE BREAK (SWEATING), LATE – CONJ HOLE POSITIVE SEIDEL

• SHALLOW AC, CHOROIDAL DETACHMENT IN SEVERE CASES

• MANAGEMENT-

• 1) LARGE DIAMETER CONTACT LENSES.

• 2) BLEB COMPRESSION SUTURES. CAN BE COMBINED WITH BLOOD INJECTION.

LATE BLEB LEAKAGE CONTD…

• 4) TRICHLORACETIC ACID

• 5) INJECTIONS OF AUTOLOGOUS BLOOD (1 -2 ML)- INTO AND AROUND THE BLEB.

• 6) REFASHIONING OF THE BLEB- CONJUNCTIVAL ADVANCEMENT , FREE CONJ AUTOGRAFT, SCLERAL GRAFT

• 7) CATARACT SURGERY MAY PRODUCE AN INFLAMMATORY REACTION WHICH MAY STIMULATE WOUND.

• COMPLICATIONS-

• CORNEAL DECOMPENSATION, PAS, CHOROIDAL HGE, INFECTION, HYPOTONY, MACULOPATHY

BLEB ASSOCIATED INFECTION• RISK FACTORS –

• THIN AVASCULAR WALL OF DRAINAGE BLEB

• BLEPHARITIS

• LONG TERM TOPICAL ANTIBIOTIC

• INFERIOR OR NASAL BLEB

• PATHOGENS -Streptococcus and Staphylococcus species), as well as Haemophilus influenzae. Moraxella species , Acremonium filamentous fungi , Neisseria meningitidis , Pseudomonas aeruginosa , and Aspergillus niger have been reported as a cause of delayed-onset endophthalmitis in patients with filtering blebs

• BLEBITIS – PUS IN BLEB , NO UVEITIS,NORMAL RED REFLEX

• MANAGEMENT- CONJ SWAB

• TOPICAL OFLOXACIN & CEFUROXIME (OR VANCOMYCIN 50 mg/ml) HOURLY

• ORAL CO-AMOXICLAV 625 mg TDS(/ AZITHROMYCIN 500mg OD ) AND CIPROFLOXACIN 750 mg BD * 5 DAYS

BLEB RELATED ENDOPH

• WHITE MILKY BLEB CONTAINING PUS

• SEVERE ANT UVEITIS- HYPOPYON

• VITRITIS ,IMPAIRED RED REFLEX

• MANAGEMENT –

• TOPICAL /SYSTEMIC THERAPY AS FOR BLEBITIS

• INTRAVITREAL ANTIBIOTICS

OTHER COMPLICATIONS

• CATARACT – DUE TO IRIDO CORNEAL TOUCH, TRAUMA, MMC, INFLAMMATION, HYPOTONY

• PTOSIS , SQUINT WITH SUP RECTUS BRIDLE

• ASTIGMATISM

• WIPE OUT OF VISUAL FIELD-

• AN IMMEDIATE POSTOPERATIVE UNEXPLAINED VISION LOSS AND IS A RARE COMPLICATION IN END-STAGE GLAUCOMA.

• PATIENTS WITH ADVANCED FIELD LOSS, WITHIN 10 DEGREES OF FIXATION

• PRE AND POST OP HYPOTONY,HYPOTENSION, PERIBULBAR/RETROBULBAR BLOCK ARE RISK FACTORS

• CHECK IOP FEW HRS AFTER SURGERY TO DETECT IOP SPIKE

THANKS