What to do when blebs start to fail
Bleb failure can often be avoided with well-managed trabeculectomy and effective postoperative care.
Take-home message: Bleb failure can often be avoided with well-managed trabeculectomy and effective postoperative care.
By Nancy Groves; Reviewed by Dr Keith R. Martin, FRCOphth
When blebs start to fail, ophthalmologists need a systematic approach, and the first principle is that prevention is better than cure for these situations.
In addition, intervention sooner rather than later is also better for these patients, according to Dr Keith R. Martin, FRCOphth, professor of ophthalmology, University of Cambridge, Cambridge, England.
Steps most likely to avoid failure, he said, are:
- careful trabeculectomy,
- meticulous technique,
- watertight closure of the limbus,
- control of scarring, and
- attentive management of postoperative inflammation.
“The first days and weeks following surgery are a critical period,” Dr Martin said. “During this time, adjustment or lasering or removal of flap sutures can be effective. Bleb massage can be useful in some of our patients, although it’s important to recognise that this is not a substitute for control of the inflammation by other methods.”
The next management principle is to identify the site of failure.
“If your bleb is flat, it’s likely that you have either obstruction of the internal ostium, scarring of the flap, or a leak,” Dr Martin said. “Gonioscopy is key here in the assessment, and it’s often neglected. With gonioscopy, you can see directly if the internal ostium is obstructed or if there’s no visible sclerostomy, in which case needling is very likely to be unhelpful.”
Planning the surgical intervention
Once the site of failure has been found, intervention can be planned.
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