Page 85 - HA Convention 2015

Masterclasses

MC6.1 Advances in Glaucoma Management 16:15 Convention Hall C

Management of Open Angle Glaucoma Monday, 18 May
Yung HW
Department of Ophthalmology, Tuen Mun Hospital, Hong Kong

Glaucoma is the most common cause of irreversible visual impairment and blindness globally. It is a spectrum of diseases
characterised by progressive retinal ganglion cells death, axonal losses and optic nerve damage.

Primary open angle glaucoma is highly prevalent. It is characterised by adult onset, a raised intraocular pressure of more
than 21 mmHg, an open drainage angle, glaucomatous optic nerve head damage and visual field loss.

Recently, more and more patients with a normal intraocular pressure but otherwise characteristic primary open angle
glaucoma features were found, and these belong to the group of “normal tension glaucoma”.

The recent development of Optical Coherent Tomography can measure the thickness of optic nerve fibre around the optic
nerve head. It makes earlier diagnosis possible, and also eases monitoring of early stage of diseases. As with other chronic
diseases, monitoring is of utmost importance, these include monitoring of intraocular pressure, optic disc changes and visual
field changes.

The aim of treatment is to slow down the progression of optic neuropathy. It is important to define a target intraocular
pressure for individual patient. Treatment options include medical treatment, laser and surgery. Medical treatment includes
topical prostaglandin analogues, beta blockers, carbonic anhydrase inhibitors and alpha agonist, which are very effective to
most patients in lowering intraocular pressure. Selective Laser Trabeculoplasty provides a safe though short lasting option
for some patients who are allergic to medications, or do not want to undergo surgery. Classical Trabeculectomy procedure
remains the main form of surgical treatment, though the use of glaucoma shunt has increased popularity recently. The recent
development of Micro Invasive Glaucoma Surgery (MIGS) such as Trabecular Micro-bypass Stent, Phaco-Trabectome,
Canaloplasty procedure provides an option to lower intraocular pressure and may help manage glaucoma patients daily in
future.

MC6.2 Advances in Glaucoma Management 16:15 Convention Hall C

Management of Angle Closure Glaucoma HOSPITAL AUTHORITY CONVENTION 2015
Lai J
Department of Ophthalmology, The University of Hong Kong, Hong Kong

Primary angle closure glaucoma (PACG) is a glaucomatous optic neuropathy that is secondary to increased intraocular
pressure (IOP) caused by closure of the drainage angle. Angle closure is the result of apposition or adhesion (PAS) of the
peripheral iris to the trabeculum. The mechanisms of closure include plateau iris configuration, pupillary block, phacomorphic
angle closure, aqueous misdirection and mixed types. PACG is subdivided into acute and chronic subtypes. The acute form
is highly symptomatic, and results from sudden appositional closure of the angle leading to dramatic rise in IOP. Acute angle-
closure, if left untreated, can lead to irreversible optic nerve damage. Chronic angle-closure glaucoma tends to be more
insidious in onset. It may be a sequel of acute angle-closure, or it may also arise de novo. Acute primary angle-closure is
managed by a two-step approach. The first step is rapid reduction of IOP to relieve symptoms and to prevent irreversible
optic nerve damage. This is achieved by systemic and topical IOP-lowering medications or by laser peripheral iridoplasty.
The second step is to prevent recurrence of the pupillary block, and this is achieved by laser peripheral iridotomy (LPI). This
two-step approach works effectively in the majority of cases of acute angle-closure.

Cataract surgery is becoming more popular as the second-stage procedure of choice. Removal of the cataract/lens may
eliminate other angle closure factors as well as pupillary block. Therefore the chance of development into the chronic type
is minimised. After cataract surgery, the anterior chamber becomes deeper, the angle becomes wider and the IOP becomes
lower. Cataract surgery thus becomes an important treatment tool in the management of PACG by reducing the number of
glaucoma medications and glaucoma surgery.

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