Glaucoma Testing and Treatment

We at Colony Eye Care Center are dedicated to detecting and treating glaucoma.  It can be the silent stealer of vision, and annual eye exams are the best way to detect this disease.  We are glaucoma licensed therapeutic optometrists, and are able to detect, diagnose, and treat glaucoma.

Your eye produces a fluid inside the eye called aqueous.  It is in constant production, and it will flow out of the eye through a drainage system called the trabecular meshwork.  This constant production and outflow mechanism causes the eye to have a fluid pressure known as intraocular pressure (IOP).  If the IOP is elevated beyond a normal level, it can cause damage to the nerves in the retinal nerve fiber layer (RNFL).  This will eventually cause permanent vision loss if left untreated or uncontrolled.  There are different treatments, or combinations of treatments to treat glaucoma.

Glaucoma

Glaucoma

Types of Glaucoma

  • Primary Open Angle Glaucoma (POAG)– most common type of glaucoma- usually no pain associated with this type, and no noticeable vision loss until it reaches the more advanced stages.
  • Normal Tension Glaucoma (NTG) – this type also has no pain and no noticeable vision loss until the advanced stages.  This type does not have elevated IOP, and can be difficult to initially diagnose.
  • Angle Closure Glaucoma – the anatomy of the eye can cause a blockage to the outflow drainage system, and causes an acute rise in IOP.  This type of glaucoma usually has symptoms of pain or achiness and cloudiness to vision that can cause halos around lights.  This is a medical emergency, and should be treated quickly to lower the IOP.
  • Secondary Glaucoma
  • Pediatric Glaucoma

Treatments

  • Medications:  used to lower the IOP.  Usually drops that are put in the eye at least once a day, and sometimes more often.
  • Surgery:  may be used if medications don’t control the pressure well enough.  This can be laser or cutting surgery, and may also be used instead of using medications.
  • Combination:  some patients have more advanced or harder to control glaucoma, and may need both surgery and medications to control the disease.

Testing

  • Tonometry:  used to measure IOP (intraocular pressure).  Performed with a device that touches the eye to measure the pressure, and may be done with a device that blows air on the eye.
  • Visual Field Testing:  uses varying devices to show a stimulus to a patient, and it measures the sensitivity to the stimulus.
  • Retinal Nerve Fiber Layer (RNFL) devices used to measure the thickness of the nerve layer in the retina (starts to thin in glaucoma).  We have a device that uses a scanning light taking 27,000 samples per second to develop a 3-D view of the optic nerve head.  This is called optical coherence tomography (OCT).
  • Gonioscopy:  this is used to view and assess the anatomy of the eye, and it’s drainage system.
  • Pachymetry:  this measures the thickness of the cornea.  Corneal thickness can affect the way in which we read the IOP.

RISK FACTORS

  • Family history (highest correlation if you have a sibling with glaucoma)
  • Race (highest risk with Blacks)
  • Elevated IOP
  • IOP asymmetry
  • Thin cornea
  • Optic nerve cupping
  • Optic nerve asymmetry
  • Optic disc hemorrhage
  • Prior Trauma
  • Narrow angle anatomy (can close off drainage system causing pressure to go up)
  • High myopia
  • Pigment dispersion (Krukenberg’s spindle)
  • Steroid responder (causes pressure to go up)
  • Borderline screenings

**There is a link to a very good resource on glaucoma.  This non profit organization does a great job of going into detail all the things above:   www.glaucoma.org

Simulation for the loss of vision in progressive glaucoma:  www.xalatan.com/tools/simulator.aspx

Glaucoma is a serious disease that could silently steal away your vision.  It can be controlled, but it has to be detected first.  Please call today to make an appointment so we can screen for one of the leading causes of blindness.