Trabeculectomy

Trabeculectomy is performed mostly in patients with poor medical control.

The scheme of examination would be according to the following pattern.

1.     Trabeculectomy itself – Bleb status including leakage, PI status, Depth of AC, IOP

2.     Cause of Glaucoma – whether primary and or secondary; and the signs of secondary glaucomas

3.     Signs of previous treatment/s – Drug toxicity, punctal stenosis, ALT/SLT scarring in angle

 

VISUAL ACUITY

The visual acuity is variable. The procedure is usually performed in patients with advanced disease who may still have good central vision but advanced field defects.

FACE AND FACIAL SYMMETRY        

Look for facial features of patients with anterior segment cleavage syndrome.

EYELIDS AND ADNEXA

Lagophthalmos/blepharospasm due to symptomatic bleb

CONJUNCTIVA

Bleb Size & status – uniformly raised diffuse bleb, localized bleb, flat bleb.

Limbus-based or fornix-based procedure.

Leakage (bleb leak, bleb dehiscence, sweating) – use Fluorescein dye (Seidel Test)

Vascularity (normal, avascular, congested),

Cyst formation (tenon cyst/ring of steel)

Blebitis signs

Failure (assessed in correlation with the IOP)

Overhanging Bleb

 

CORNEA

Microabrasions on the cornea and Dellen–Bleb dysesthesia

Toxicity due to antifibrotic agent

Releasable suture/s

Signs of causes of secondary glaucoma

Pigment on endothelium – ACG, Krukenberg spindle in PDS, PEX

Corneal endothelial changes – ICE syndrome (hammered silver/beaten bronze appearance)

Posterior embryotoxon – Anterior segment cleavage syndrome

 

SCLERA

Scheie Procedure – amputated scleral flap with open sclerostomy underneath conjunctiva.

GONIOSCOPY

TM scarring – Angle recession glaucoma

Sampoleisi Line – PDS, PEX

Pigmentation – Hyperpigmentation 360 degree degree (PDS), more pronounced inferiorly (PEX, Post traumatic/surgical)

Angle recession & other signs of trauma (iridodialysis, cyclodialysis)

Berlin Nodule & other chronic uveitic changes in meshwork like trabecular scarring and/or sclerosis secondary to chronic trabeculitis.

Synechial angle closure

Fibrovascular sheath in Neovascular glaucoma

Migrated endothelium or epithelium from the cornea to the iris across the TM in cases of ICE or Epithelial down growth, respectively.

IRIS AND PUPIL

Patency of PI (retro illumination)

Other PI (surgical or laser)

Pupil Block, Iris Bombe – peripheral AC shallower as compared to center.

Aqueous misdirection – relatively similar shallowing of peripheral and central AC

Iridodialysis/cyclodialysis

Signs of causes of secondary glaucoma

PEX - Gray white dandruff like deposits at the pupil border along with moth-eaten Transillumination defects.

PDS – radial mid-stromal transillumination defects with deep anterior chamber.

Uveitic glaucoma - Posterior synechiae, iris nodules

Anterior segment cleavage syndrome – Posterior embryotoxon,

Rubeotic Glaucoma -

LENS

Cataract

Glaucomflecken

Pigment deposition on the lens.

VITREOUS

Fluid pockets may be seen (lacunae on b-scan) – Malignant Glaucoma

 

POSTERIOR SEGMENT

Choroidal effusion / Suprachoroidal hemorrhage

Glaucomatous optic nerve head changes and peripapillary changes (especially the alpha & beta zones and, NFL under

IOP

Hypotony

Raised IOP

 

FELLOW EYE

Look for the cause of trabeculectomy in the fellow eye and the indications for trabeculectomy in this eye.

ANCILLARY TESTING

Anterior Segment OCT to look at bleb dynamics and angle opening.

Posterior segment OCT to assess for glaucoma status

B-Scan

Visual Fields