PRIMARY CONGENITAL GLAUCOMA.ppt

primary congenital glaucoma

1. DR. SALMAN AHMAD KHAN
PGR EYE UNIT 2
SERVICES HOSPITAL LAHORE

2. Primary Congenital Glaucoma
Primary Congenital glaucomais a rare form of
glaucomawith an incidence of 1:10,000.
Affected infants may be born with a high intraocular
pressure or may develop an increased IOP within the
“first weeks of life".
Both eyes are usually involved, but to varying severity
Boys are affected slightly more frequently than girls.

3. CLASSIFICATION:
True Congenital Glaucoma (40%) in which
the IOP is elevated during intrauterine life.
Infantile Glaucoma (55%) which manifests
prior to age 3
JUVENILE GLAUCOMA: the least common,in
which IOP rises between 3 and 16 years of age.

4. The Cause
It is usually sporadic, but approximately 10% are
AR with variable penetrance. Several genes have
been implicated, prominently CYP1B1
The IOP elevation is caused by the failure of the
anterior chamberangle and the trabecular
meshworkto develop appropriately during
intrauterine development(Trabeculodysgenesis)
In these infants, the aqueoushumor does not
properly drain, but since the production of
aqueoushumor is nevertheless normalso the IOP
is high

5. Legal blindness is the outcome in at least 50% of eyes
Secondary infantile glaucoma can be caused by a range
of conditions including tumours such as
retinoblastoma
persistent fetal vasculature (persistent hyperplastic
primary vitreous)
uveitis.

6. Figure1: The normal chamber angle: on the left is a
histological cross-section; on the right is a drawing of the same
Figure 2:An underdeveloped chamber angle

7. Consequences of an Increased IOP
during Infancy
Depending on the IOP level, glaucomatous damage
is inevitable after weeks, months or even years.
This basically occurs via the same mechanisms as in
the adult.
In addition to optic nervedamage, the globe (eyeball)
enlarges because the sclerain the eye of a baby is
distensible.

8. Enlargement of the globe (buphthalmos) is a result of
elevated intraocular pressure.
The anatomic landmarks are displaced.
The anterior chamber is deep
All segments of the outer eye, but especially the cornea
and sclera, expandprincipally at the corneoscleral
junction.
The thinned sclera appears blue due to visualization
of underlying uvea.
Complications include myopia and lens subluxation.
Clinicalappearance

9. However, certain layers of the corneaare not very
elastic, and stretching may result in small tears(Haab
striae) that cause a certain degree of corneal
opacification.They are curvilinear healed breaks in
descemet’s membrane.
Haab striaeHaab striae

10. Corneal epithelial edema caused by elevated
intraocular pressure and failure of the corneal
endothelial pump mechanism.
Epiphora, photopobia and blepharospasm (clinical
triad)

11. If the IOP is lowered, this opacity is partially
reversible.Also optic disc cupping regresses in infants.
As a result of the optic nervedamage and/or corneal
opacity, children with congenital glaucomamay be
permanently visually impaired.

12. Diagnosis of
Congenital Glaucoma
Clinical clues
Enlarged eyes; tearing, and photophobia
(avoidance of light).
Often, babies also rub their eyes.
If CG is suggested, a thorough Examination
Under General Anesthesiais necessary.
IOP measurement should be performed first
Intravenous ketamine lowers IOP less than other
agents

13. It is preferable where possible for this to be
measured in a conscious or sedated child; 10–12
mmHg is normal.
Anterior chamber examination with an operating
microscope and/or portable slit lamp.
Optic disc examination; asymmetry or a cup/disc
ratio of >0.3 is suspicious
Corneal diameter measurement; >12 mm prior to
the age of one year is highly suspicious.

14. Gonioscopy using a direct goniolens may be normal or
reveal trabeculodysgenesis, vaguely characterized by
an anteriorly located iris insertion and a hypoplastic
appearing peripheral iris.
Refraction.

15. EPIPHORA
HAAB’S STRIAE
CORNEAL EDEMA
HIGH IRIS INSERTION
ON GONIOSCOPY

16. Infantile Glaucoma
Infantile glaucomais also congenital glaucoma
However, intraocularpressure starts to rise at some
time during the first years of life,prior to age 3.
The cause for this IOP increase is basically the same as
in congenital glaucoma, but it occurs later since the
anterior chamberangle is more mature than when
glaucoma is present at birth.
The IOP may be normal during the first years of
childhood and then gradually increase.

17. Juvenile Glaucoma
Juvenileglaucoma is an IOP increase that occurs in an
older child or young adultfrom 3 to 16 years of ageand
is often inherited.
During a thorough examination, the ophthalmologist
may find discreteevidence of an incomplete
maturation of the chamber angle,

18. Treatment
The treatment is primarily surgical.
Different surgical procedures
Goniotomyfor clearcorneas
Trabeculotomy forhazycorneas
,successratessimilar
Trabeculectomy andShunt procedures
only whengoniotomyor trabeculotomy
fails
Ahmed glaucoma valve in refractory
glaucoma cases.

19. GONIOTOMY
Involvesmakingahorizontalincisionatthe
midpoint ofthesuperficiallayersofthe
trabecularmeshwork
Mayneedtoberepeated
Eventual success rate is about85%
Resultsarepoorifthecornealdiameteris
14mmormorebecauseSchlemm’scanal
obliterated.

20. The goniotomysurgery
involves enteringthe
anterior chamber with a
sharp goniotomyknife
and making an opening
incision through the
abnormally developed
trabecular meshwork to
allow greater outflow of
the aqueous fluid and
thereby, lower the IOP
Often 120 degrees (out of
360 degrees total)ofthe
trabecularmeshworkcan
be treatedwith
goniotomyinasingle
setting

21. Goniotomy. A fine surgical knife is used to open the drainageangle
(trabecular meshwork) in order to lower the intraocularpressure.

22. TRABECULOTOMY
Ifcornealcloudingpreventsvisualizationof
theangleorwhenrepeatedgoniotomyhas
failed
Partial thickness scleral flapis fashioned
Schlemmcanalisfoundandatrabeculotome
isinsertedintoSchlemmcanalandthen
rotatedintotheanteriorchamber
Technicallyhighlydemanding,requires
previousexperience,andgoodanatomical
landmarkstoachievepredictableresults

23. Schlemmcanalmaybedifficulttocanalize
becauseofhypoplasiaor angleanomaly
Trabeculotomysurgery involves making an
external incision and identifying the
Schlemm’scanal from the outside, inserting
a fine instrument into the Schlemm’scanal,
and breaking through the trabecular
meshwork to increase the aqueous outflow
Typically, 120-140 degrees of trabecular
meshwork can be treated by trabeculotomy
in a single surgery.

24. If one surgical technique is unsuccessful in
decreasing the IOP, the other technique can be
utilized in a fresh area of the trabecular meshwork
(the area not previously operated upon) to increase
the success of the surgery
Even after initial control of the intraocular pressure
is established with surgery, a periodic monitoring is
necessary to ensure the IOP doesn’t increase again
and the glaucoma go out of control.

25. Trabeculotomy. A trabeculotome instrument is used to
open the drainage angle (trabecular meshwork) in order
to lower the intraocular pressure.

26. MEDICAL TREATMENT
Temporary measures to control IOP and to clear
cloudy cornea prior to surgery
Administer beta-adrenergic antagonists,
CAI’s(carbonic anhydrase inhibitors)
avoid alpha2-adrenergic agonists under 3 years
occlude nasolacrimal drainage system for 2
minutes after administration.
Medications can be used as an adjunct therapy
either before or after the surgical treatment

27. Medications may be utilized temporarily after the
diagnosis until surgery can be performed. If the
initial surgery fails to completely control the IOP,
topical medications can be used to bring the
glaucoma under control
The systemic side effects of topical medications are
greater in infants than in adults because of the
smaller body mass.
Because of potential systemic side effects, the first
line of medications that are commonly employed is
the topical carbonic anhydrase inhibitors
After the CAI, the next choices are topical
prostaglandin analogs or beta blockers

28. The prostaglandin analogs (e g.latanoprast) appear
to be safe in children; however, there are no long-
term data on the safety of these medications in
children. Topical beta-blockers(eg .timolol) should
be used with caution in children because of the well-
known systemic side effects
•Finally, topical alpha-2 agonist (brimonidine)
should be AVOIDED in infants because it’s been
associated with severe respiratory depression
(breathing difficulty)

29. PROGNOSIS
Good in asymptomatic patients diagnosed before
24 months.
Guarded in symptomatic patients diagnosed after
24 months even if IOP controlled after surgery.

30. DIFFERENTIAL DIAGNOSIS
Cloudy cornea
Birth trauma.
Rubella keratitis; congenital rubella is also
associated with congenital glaucoma.
Metabolic disorders such as mucopolysaccharidoses
and mucolipidoses.
Congenital hereditary endothelial dystrophy.
Sclerocornea.

31. Large cornea
Megalocornea.
High myopia.
• Epiphora
Delayed/failed canalization of the nasolacrimal
duct.
Lacrimation secondary to ocular irritation, e.g.
conjunctivitis, aberrant eyelashes, entropion.