glaucoma /ophthalmology

1. PIGMENT DISPERSION SYNDROME
Dr. Aditi Singh

2.  Described by : Sugar and Brown 1949

3.  Pigment dispersion syndrome (PDS) and pigmentary
glaucoma (PG) :
 two successive stages of the same disease process
characterized by –
 disruption of the iris pigment epithelium
 and deposition of the dispersed pigment granules
throughout the anterior segment

5. EPIDEMIOLOGY
 Young
 Myopic
 Male
 Experiences blurry vision or eye pain after exercise

6. PATHOPHYSIOLOGY
 Concave iris contour that allows apposition of its
posterior surface to the zonular bundles.
 Friction between zonules and the peripheral iris - cause
of the pigment liberation.
 Reverse pupillary block mechanism may exist : “flap
valve,”

7. Accumulation of pigment granules in the intertrabecular
meshwork
Increases resistance of aqueous egress elevating IOP
Elevating IOP.

8.  Exercise (jogging, playing basketball, and bouncing
during dancing) can cause the release of pigment
as a result of pupillary movement.
 Pharmacologic pupillary dilation - may result in
significant pigment liberation into the anterior
chamber.
 This pigment liberation may be accompanied by
IOP increase.

9. CLINICAL FEATURES:
 Myopes, young males,caucacians, positive family history
 Cornea: Corneal endothelial pigment appears as a
central, vertical, brown band (Krukenberg spindle)

10. Iris: Loss of iris pigment appears as a midperipheral,
radial, slit-like pattern of transillumination defects.
Difficult to appreciate in dark iris.

11.  Lens / Zonules : Interrupted lines on the posterior
peripheral surface of the lens – Zentamayer ring or
Scheie’s stripe.
 Angle: Wide open.
Heavy dark brown to black pigmentation.
Homogenous .
Prominent inferiorly.
 The iris is inserted posteriorly into the ciliary body,
configuration : concave

12.  Posterior segment:
lattice degeneration - 20% of patients
retinal breaks- 11.7%
rhegmatogenous retinal detachments
requiring surgery may occur in 3.3%
oOptic nerve examination:
Size , PPA, RNFL defect, disc h’ges, NRR thinning

13. TEMPORAL EVOLUTION OF PDS
 Conversion of PDS to PG – slow and may take years
slow spontaneous resolution irreversible damage to angle
 transillumination defects may disappear,
 the IOP may return to normal,
 the trabecular meshwork pigmentation may decrease.
Pigment reversal sign ( burned out )

14. DIFFERENTIAL DIAGNOSIS
 Disorders causing anterior segment pigment dispersion :
 exfoliation syndrome (XFS),
 diabetes,
 herpetic eye disease,
 iris pigment epithelitis,
 radiation,
 trauma,
 iris pigment epithelial cysts,
 ciliary
 body cysts,
 iris nevus, and
 melanoma or melanocytoma of
 the anterior and posterior segment

15. .
Features Pseudoexfoliation
syndrome
Pigment dispersion
syndrome
Transillumination
defects
Peripupillary Radial mid peripheral
TM pigmentation Patchy homogenous
Age group > 60 yrs ( older) 20- 30 yrs (younger)
whitish granular
deposits
Present Absent

16. TREATMENT
 The treatment of PDS/PG is aimed at reversing the iris
concavity, preventing pigment release, and
therefore lowering IOP.
 Miotics:
 reverses the iris concavity and eliminates iridozonular
contact.
 Tension over the scleral spur, miotics increase aqueous
outflow through the trabecular meshwork.
 Low-concentration pilocarpine.
 Peripheral retina should be examined carefully

17.  Prostaglandin analogues: Increasing uveoscleral
outflow.
 Agents that lower IOP by reducing aqueous production
hypothetically –
 may diminish the rate of clearance of the pigment from
the trabecular meshwork, possibly exacerbating the
disease process.
 these agents may inhibit relative pupillary block, which
is therapeutic in PDS.

18. LASER IRIDOTOMY
 Equalizes pressures between the anterior and posterior
chambers,
 Flattens the iris,
 Eliminates iridozonular contact, and
 Occasionally decreases further liberation of pigment
 Proper patient selection.
 Ideally, patients should still be in the pigment liberation stage.
 In young patients with iris concavity, active release of pigment
and ocular hypertension, LI may be of benefit for years.

20.  Argon laser trabeculoplasty and selective laser
trabeculoplasty
 Alternative treatments to lower IOP, mostly in young
pigmentary glaucoma patients.
 The success rate of argon laser trabeculoplasty
(ALT) in PG is greater in younger patients than in
older ones and decreases with age

21.  Trabeculectomy :
 Not responding to medical / laser therapy.
 MMC to be used in lower concentration for lesser
time.
 Outcomes comparable /better than of POAG