- Katie, a 38 year old female, presented in private practice for an examination.
Her main presenting symptom was having difficulty with reading fine print
and general blurriness in sight.
- Previous ocular history: She had been prescribed spectacles in her early
twenties for reading. Distance vision is quite clear and she is currently using
hobby glasses to read more comfortably.
- Personal Medical History: No reported medical conditions, with no
prescribed medication being taken.
- Family Medical and Ocular History: No reported history of glaucoma,
cataracts, unusual eye conditions, blindness, heart or blood pressure problems,
WHAT TESTS WOULD YOU RUN TO
CONFIRM A DIAGNOSIS?
Measure the pressure in your eye (tonometry)
- Tonometer- measures eye pressure.
- Normal eye pressure generally ranges between 10 and 21 mmHg
- Glaucoma can have damage to their optic nerve lower than 21 mmHg.
Inspect your optic nerve (ophthalmoscopy)
- Inspects your optic nerve for signs of damage using an ophthalmoscope
Test your side, or peripheral, vision (visual field test)
- The visual field test will check for blank spots in your vision
Measure the thickness of your cornea — the clear window at the front of the
- A very thin cornea may increase your risk of glaucoma.
Glaucoma is the result of damage to the optic nerve. As this nerve gradually
deteriorates, blind spots develop in your visual field. For reasons that doctors
don't fully understand, this nerve damage is usually related to increased pressure in
Elevated eye pressure is due to a buildup of a fluid (aqueous humor) that flows
throughout your eye. This fluid normally drains into the front of the eye (anterior
chamber) through tissue (trabecular meshwork) at the angle where the iris and
cornea meet. When fluid is overproduced or the drainage system doesn't work
properly, the fluid can't flow out at its normal rate and pressure builds up.
Glaucoma is one of the leading causes of blindness in the United States. It can
occur at any age but is more common in older adults and tends to run in families.
In some people, scientists have identified genes related to high eye pressure and
optic nerve damage.
Taken from a PubMed journal, it has been found that several observations
noted by early investigators supported the supposition that in most cases,
congenital glaucoma is determined by genetic factors. The genetic
heterogeneity of PCG was confirmed by genetic linkage studies conducted in
the 1990s when the authors determined that CYP1B1 is the congenital
glaucoma gene at the GLC3A locus. The coding sequence of CYP1B1 has
been subjected to extensive screening in familial and sporadic cases of
glaucoma from numerous countries and from a large number of ethnic
groups. These studies have provided evidence for extensive allelic
heterogeneity at the GLC3A locus. This article also discusses the molecular
evidence for reduced penetrance in congenital glaucoma and the phenotypic
heterogeneity of CYP1B1 mutations, mouse models of CYP1B1, and the
biochemistry of CYP1B1.
GENETICS AND BIOCHEMISTRY
- Glaucoma medication: Lowers eye pressure.
- Beta blocker: Slows heart rate and decreases blood pressure. When taken in
eye-drop form, it reduces eye pressure.
- Laser surgery: Surgery using an intensely hot and focused beam of light to
remove tissue and control bleeding.
- Trabeculoplasty: Using a laser to improve fluid drainage in the eye and
reduce eye pressure.