P Caring for Children With Congenital Glaucoma Clinical Update

Clinical Update
tools and techniques
Caring for Children
With Congenital Glaucoma
by miriam karmel, contributing writer
rimary congenital glaucoma,
though relatively rare, is the
most frequent childhood
glaucoma and is an important cause of blindness in
children worldwide. It shares many of
the features of a disease that is common
in older adults: elevated IOP, optic nerve
damage and visual field loss. Yet the
approach to therapy and long-term
management of PCG reveals a general
truth of pediatric medicine: Kids cannot be treated like miniature adults.
Given the infrequency of the disease
—it occurs in about 1 in 10,000 births
—most ophthalmologists may never
encounter a child with glaucoma. “It’s
a rare condition in the United States,”
said Sharon F. Freedman, MD, associate
professor of ophthalmology and pediatrics at Duke University and one of a
handful of pediatric glaucoma specialists in this country. “But such a patient
may walk into your office tomorrow.”
An ophthalmology resident could
spend three years in training and never
encounter a single case, said David S.
Walton, MD, clinical professor of ophthalmology, Harvard University. So
physicians encountering PCG should
not hesitate to seek support. “Refer the
patient or consult others who are familiar with the childhood glaucomas,” Dr.
Walton said.
Andrew G. Iwach, MD, associate
clinical professor of ophthalmology at
the University of California, San Francisco, agreed. “Treating congenital glaucoma can be very labor intensive, very
time consuming,” he said. “You need a
D AV I D S . W A LT O N , M D
Stop the Pressure
Three-month-old infant with PCG, corneal enlargement and opacification.
team approach.” The team may consist
of a glaucoma specialist with the skills
to perform angle surgeries for congenital glaucoma, a pediatric ophthalmologist and the staff to help with patching
or contact lenses that may be required.
Origins and symptoms. PCG is a
hereditary condition, resulting from
abnormality of the trabecular meshwork, possibly due to a developmental
arrest, causing increased resistance to
aqueous outflow. It accounts for
approximately 55 percent of primary
pediatric glaucomas.
Photophobia, epiphora and blepharospasm are hallmarks of the disease.
In many cases, the cornea appears
enlarged and cloudy from an overburdening of the corneal endothelium.
“Any time I hear a parent say, ‘My kid
has such big, beautiful eyes,’ that scares
me,” Dr. Iwach said.
Though it’s a rare condition, “you
want to have a high index of suspicion,”
when those symptoms occur, said Terri
Pickering, MD, a pediatric ophthalmologist and associate of Dr. Iwach at the
Glaucoma Center of San Francisco.
Tr eat These Kids,
But Not Like Adults
Unlike adult glaucoma, where drugs are
the first-line treatment, children with
PCG should be considered for surgery
first, with drugs as a last resort. “Medications typically don’t work and tend
to have more side effects in children
because their enzyme-metabolizing
systems aren’t as well developed,” said
Dr. Pickering.
e y e n e t
s e l e c t i o n s
“If it’s truly primary congenital glaucoma, there’s a good chance that after
one or two goniotomies, the child may
have normal pressures and only need to
be monitored, and will lead a full life,”
Dr. Iwach said.
When the cornea is clear enough to
enable confident viewing of the filtration angle, goniosurgery is the first-line
surgical treatment for children with
PCG. Alternatives are trabeculectomy
and drainage tubes. As Dr. Walton noted,
“Goniosurgery needs to be seriously
considered for every patient. Exceptions
to that may be newborns with severe
angle defects and with corneal opacification,” explained Dr. Walton, who
treats those patients with tubes.
Don’t go it alone. Dr. Iwach, who
describes himself as “passionate” about
goniosurgery, cautioned that it is “very
delicate surgery,” requiring “two surgeons, four hands,” as well as special
lenses and knives.
Dr. Freedman echoed that concern.
“A pediatric ophthalmologist who hasn’t
done one in three years probably
shouldn’t be doing it. Or an adult glaucoma specialist who hasn’t done a
patient under 25 probably should partner with someone who works with kids.
You want to partner with, or hand off
to, someone who is comfortable with
this surgery in children.”
“It doesn’t always work, but when
it does, it’s a great home run,” said Dr.
Iwach. “It provides significant lifelong
advantages over filtering surgery or
In fact, relapse following successful
goniotomy is unusual, and normalization
of IOP persists. “I’ve followed children
one year after, five, 10, 15—they’re cured,”
Dr. Walton said. “They’ve never seen an
eye drop.”
Follow up that amblyope. The glaucoma may be cured, but these children
are at high risk for amblyopia. In fact,
much of the vision loss in these patients
isn’t from glaucoma, but from amblyopia, Dr. Walton said.
Dr. Freedman added, “I’ve seen kids
with beautiful pressures, but who have
an eye legally blind from amblyopia.”
Most doctors, unless they are accustomed
to working with children, become so
s u p p l e m e n t
Delays Can’t Stop This Sand Castle Builder
he strong chance for a cure in congenital glaucoma makes delayed
diagnoses very frustrating to
experts like Dr. Walton. One such case
involved Sophia Vilim, who came under
Dr. Walton’s care but not until she was
diagnosed at age 2 1/2.
Sophia’s mother, Claudia Vilim, recalls
when she first noticed that anything was
wrong. “One morning Sophia woke up and her eyes were bright red. She was probably four to six months at that point.” Sophia’s pediatrician diagnosed conjunctivitis and blocked tear ducts. “The pediatrician thought it was something common
and would go away,” Ms. Vilim said.
An ophthalmologist correctly diagnosed primary congenital glaucoma, but by
then Sophia was over 2 years old, and the condition was advanced. Sophia went to
a specialist in Chicago, but even the specialist, who sees about 30 children a year
with glaucoma, referred her to Dr. Walton.
After several goniotomies, Sophia’s pressure, without eye drops, has been controlled in both eyes now for almost four years. Even so, because of the delayed
diagnosis, Sophia, who is now 6 and in kindergarten, has best corrected vision of
20/300 and some field restrictions.
focused on intraocular pressures that
they might forget to check for amblyopia,
she said.
Pr escr iption: Teamwork
“The bottom line: This is a team
approach,” said Dr. Freedman. Ideally,
a child with glaucoma under the age of
10 should be cared for by a pediatric
glaucoma specialist, she said. But given
that there are only two or three dozen
in the country, the team might consist
of a pediatric ophthalmologist, together
with a glaucoma specialist. A family
pediatrician might also be in the loop.
The ophthalmologist must feel confident examining children. “Development
of examination skills is very important,”
Dr. Walton said. That means being able
to measure eye pressures and assess the
anterior segment in patients who can be
rambunctious. “In some sense, it’s the
most mundane expectation, but the
hardest thing often is to get a good eye
pressure measurement.” He added that
IOP in a struggling child may be falsely
elevated, and conversely low in an anesthetized child, but that mild sedation
should not affect eye pressure.
Long lives for little eyes. Finally,
there is a range of issues that might not
occur to an ophthalmologist, “if they’re
not thinking from the little person’s
point of view,” Dr. Freedman said. You
have to think about sports and fun and
social activity, and the attendant potential for eye injury in kids already at risk
for visual impairment. “It’s not good
enough to say, ‘You’re 20/20 and your
pressure’s good.’”
“It’s really important, because these
children have so many years of life
ahead,” Dr. Walton said. “You’re working for and giving each child a lifetime
of vision.”
This article originally appeared in the
May, 2006, issue of EyeNet.
New Fellowship
Now, there is an opportunity for physicians to learn about the care and
treatment of children with glaucoma
through a fellowship with Dr. Walton
and the glaucoma service at the
Massachusetts Eye and Ear Infirmary.
Teresa C. Chen, MD, is associate preceptor for the fellowship. For more
information, Dr. Walton can be contacted at 617-227-3011.