This edition of Glaucoma Today features three articles on far-advanced glaucoma—one dealing with staging and counseling, one with rehabilitation, and one with regeneration. I would love to take credit for suggesting those highly appropriate subdivisions of this important topic. (I can't, but I am glad to have been asked to participate.)
For a variety of reasons, some individuals with glaucoma end up with severely excavated optic nerves and visual loss. The latter is frightening for and limiting to patients, and when it occurs, the damaged person suffers. The impact of the loss of sight, however, is highly influenced by how the person handles that loss. Here, the physician can play a positive and favorable role.
John Milton, who is thought to have had glaucoma, commented, “To be blind is not miserable; not to be able to bear blindness, that is miserable.”
After a person has lost a great deal of sight, it is easy for both the doctor and the patient to slip into the “custodial care” mentality. This is never (I repeat, never) appropriate. The patient's mindset should always be, “What can be done to allow me to live as fully as possible?” The doctor's approach should be, “What can I do to make this person's life better?”
IS THIS FAR-ADVANCED GLAUCOMA?
Whenever the vision of a patient considered to have
glaucoma continues to decline, especially despite low
pressures, the clinician's first thought should be, “Is this
really glaucoma?” That question needs a definitive
answer, and the cause of the visual loss must be understood.
The absence of another apparent reason for visual loss is not adequate justification for concluding that the
patient has glaucoma.
The physician's second thought should be, “Is this glaucoma and something else as well?” Patients with glaucoma also develop retinal detachments, cataracts, pituitary tumors, and other causes for visual loss.
Usually, just raising these questions initiates the activities that will promptly lead to the correct answers.
WHAT STAGE IS THE GLAUCOMA?
The amount of damage in the patient's better-seeing
eye determines how severely he or she will be incapacitated.
Someone with an extinguished field (35 dB of
mean defect) in the worse eye and a normal field in the
better eye can function wonderfully. A person with the
same 35 dB of loss divided equally between his or her
two eyes, however, would have severe visual difficulties. I
prefer using the Disc Damage Likelihood Scale (DDLS) as
the most objective and easiest way to assess the stage of
glaucoma.1,2 From DDLS stage 1 to 5, there will be no disability,
even if both eyes are involved. When the DDLS is
worse than 6 in both eyes, the person will definitely have
a problem with visual function.
HOW CAN FURTHER VISUAL LOSS
BE PREVENTED?
Even an increment of further deterioration in a person
who already has advanced damage in his or her betterseeing
eye will decrease that individual's ability to function
and worsen his or her symptoms. I am not a fan of “the
lower the pressure, the better” approach to glaucoma,
except in most patients with far-advanced damage. One
needs to be cautious about lowering pressure markedly in
young patients, especially myopes. In elderly patients with
almost totally excavated discs, however, lowering pressure
maximally is usually the goal. Even when the IOP falls to
around 5 mm Hg, most elderly individuals with faradvanced
glaucoma will not experience visual symptoms
due to the low pressure. Laser trabeculoplasty is usually
appropriate in patients older than 40 years who have primary
open-angle glaucoma or open-angle glaucoma in
association with exfoliation syndrome. The option of pilocarpine
is worth remembering, because it is often highly
effective in pseudophakes or aphakes.
Patients thought to have glaucoma lose vision for three reasons. First, the cause for the visual loss is something other than the glaucoma for which the person has been treated. Second, whatever the IOP, it is higher than the eye can tolerate. Third, the neurons are mortally wounded and will die no matter what is done. Even with competent care and appropriate attention to the first two of these causes, sometimes, patients will continue to lose vision from glaucoma.
HOW CAN THIS PERSON BE HELPED?
Although it is not always possible to prevent vision from
worsening, it is always possible to help the person not to
become worse. Clinicians can almost always help the person
actually become better. Losing vision can increase an individual's
awareness of the preciousness of life, the wonders of
existence, and the magnificence of relationships. Physicians
who help their patients to improve their own lives bless
their patients and themselves. To be effective in this regard
requires truly knowing patients and oneself, connecting
physically and emotionally (not just intellectually) with
patients, and being proactively but realistically positive.
George L. Spaeth, MD, is emeritus director of the William and Anna Goldberg Glaucoma Service and Research Laboratories at the Wills Eye Institute in Philadelphia. Dr. Spaeth may be reached at (215) 928-3960; gspaeth@willseye.org.
