The following is a guide to glaucoma surgery. I have created this guide to help prepare patients for glaucoma surgery. It is intended to help patients understand the “why” and “how” of glaucoma surgery.
Surgical procedures for glaucoma have been evolving over the past 100 years. Over the past 25 years, we have made large strides in improving surgical techniques and outcomes. Glaucoma surgery is intended to lower the intraocular pressure (eye pressure). By lowering eye pressure, we aim to slow the progression of the disease.
Glaucoma is defined as damage to the optic nerve. Abnormally elevated eye pressure is the most common cause of glaucomatous optic nerve damage. Some patients develop glaucomatous optic nerve damage despite the fact that they have intraocular pressures within normal range. These patients are said to have “low tension glaucoma.” Healthy people without glaucoma have eye pressures ranging from 10mm Hg to 20mm Hg. The average pressure among American adults is 16mm Hg. Therefore, glaucoma surgeries are intended to lower the eye pressure to 16mm Hg or less. Surgery attempts to lower eye pressure by creating a new “drain” to allow aqueous fluid to leave the eye. Fluid that has exited the eye through the new drain collects in a cyst-like cavity called a “bleb.” From here, the fluid enters the venous circulation (blood vessels) and leaves the orbit.
Roughly 15 to 25% of patients who have glaucoma do not have elevated pressures. These patients develop optic nerve damage even though intraocular pressure rarely reaches the mid-twenties. These patients have what we call “low tension glaucoma.” The types of surgeries performed on these patients are similar to the surgeries performed on patients with elevated pressures. The main difference in surgery for “low tension glaucoma” is that we are attempting to lower the eye pressure to 12mm Hg or less. This is a more aggressive reduction than we aim for in glaucomas due to elevated pressures (16mm or less)
WHAT SHOULD I EXPECT FROM GLAUCOMA SURGERY?
Glaucoma surgery attempts to lower eye pressure by various methods. These methods will be clearly described in the following sections. Regardless of the method used, it must be clear to patients that it takes on average 3 to 6 weeks to recover from surgery. This does not mean that the patient must be a “couch potato” during this period, but rather that they must simply “take it easy” during this recovery period. Many patients are comfortable driving one to two weeks after surgery. Some patients, however, prefer to wait at least 1 to 6 weeks before driving.
IS THERE PAIN DURING OR AFTER GLAUCOMA SURGERY?
Patients who undergo glaucoma surgery usually do not experience significant pain during or after the surgery. As with any surgery, many patients experience mild discomfort for a few weeks after surgery. Strong pain medication is not commonly needed. Most patients who undergo glaucoma surgery can achieve good pain relief with Tylenol.
The most common complaint patients express after glaucoma surgery is that they feel a “scratchy” sensation for the first 4 to 6 weeks. This is normal after glaucoma surgery! Patients actually feel the stitch used to close the surgical wound. This stitch is made of an absorbable material. This stitch dissolves over 4 to 6 weeks. The stitch does not need to be “removed” because it will dissolve automatically. The “scratchy” sensation can be reduced with artificial tears. Some patients also use lubricating eye ointments to improve their comfort.
IS THERE BLURRY VISION AFTER GLAUCOMA SURGERY?
Patients may experience blurry vision for 3 to 6 weeks after surgery. Blurred vision can be very upsetting to patients who do not expect it. However, if the 3 to 6-week recovery period is clearly explained and emphasized to the patient, many patients do not have difficulty during this period.
WILL I NEED EYEDROPS AFTER GLAUCOMA SURGERY?
Most patients do not require “glaucoma” eye drops after surgery. They do, however, require three types of post-operative eye drops for the first 2 to 3 months following surgery. The types of drops needed include:
1. An antibiotic
2. An anti-inflammatory (usually prednisone)
3. A medication to dilate the pupil (this is used to help keep the eye comfortable)
These three types of drops are used for approximately 2 to 3 months after surgery. They allow the eye to heal at a controlled speed, prevent infection, and keep the eye relatively pain-free. These medications are rarely used beyond 3 months following surgery
WHY DO WE PERFORM GLAUCOMA SURGERY?
Glaucoma surgery is an effective method of controlling the disease. The surgeries, however, DO NOT “cure” glaucoma. The goals of surgery are to lower pressure and protect the optic nerve from further damage. The surgeries do not restore sight that has already been lost. The surgeries do not improve vision. The primary goal of glaucoma surgery is to slow the progression of the disease.
The pressure reduction achieved by surgery does NOT last forever. Depending on the type of surgery performed, a patient can hope to have their pressure lowered for 6 months to 10 to 15 years. There are a host of reasons why glaucoma surgeries are not permanent. The most common cause for failure of glaucoma surgery is scarring of the newly created drainage passage. Medications are used to minimize scarring for the first few months following surgery. Over the course of a decade, there is little we can do to eliminate scarring altogether.
It is important to remember that recovery takes between 3 and 6 weeks following surgery. Many patients begin to worry that they are not healing properly if they are not completely healed by two to three weeks. It is important to share your fears with your doctors and allow them to alleviate any fears that may develop after surgery.
WHAT TYPES OF GLAUCOMA SURGERY ARE THERE?
There are four types of glaucoma surgeries
1. Trabeculectomy
2. Glaucoma Drainage Devices (Aqueous shunts)
3. Non-penetrating filtration procedures (Aqua Flow)
4. Diode laser cyclodrestruction
I will now outline each of these surgeries. The type of surgery chosen depends on the type and severity of glaucoma. Each patient has a different degree of disease. The surgeon will choose the procedure based on each individual case.
Each surgery has advantages and disadvantages. There is no “perfect” surgery. The goal is to choose the appropriate procedure for each individual patient.
GLAUCOMA SURGERY-TRABECULECTOMY
Glaucoma therapy aims to protect the optic nerve and preserve visual function. At present, this goal is achieved by lowering intraocular pressure using medications, laser treatments, or surgeries. In general, surgery is reserved for patients who have glaucoma that has not been well controlled on medications and have had complete laser treatment. Laser treatments are usually performed after a patient’s pressure becomes uncontrolled on a maximally tolerated medical regimen (MTMR)
Although laser treatments can be effective, the pressure reduction they produce is not permanent. When a patient has failed medical therapy, they usually undergo laser therapy. When laser therapy in conjunction with, or in place of, medical therapy fails, we resort to surgery. Although surgery has historically been the last treatment on our list, this thinking is changing rapidly. With advances in surgical devices and techniques, the role of surgery is rapidly growing. Surgery is no longer viewed as a “last resort.” In certain cases, surgery may be a better “first step” than either medications or laser treatments.
Glaucoma surgeries attempt to make a relatively permanent “drain” in the eye. This drain removes aqueous humor from inside the eye to an extraocular reservoir.
The creation of a hole or fistula is called a trabeculectomy. Trabeculectomy first gained widespread notoriety in the 1970’s. The procedure has been performed continuously since that time.
WHAT DOES A TRABECULECTOMY INVOLVE?
With glaucoma filtering surgery, the trabecular meshwork and sclera are excised, creating a fistula through which aqueous humor drains from the anterior chamber. The aqueous humor accumulates in the subconjunctival space, forming a filtering bleb. Although it is not known with certainty, aqueous humor within a functioning filtering bleb is thought either to drain through the conjunctiva into the tear-film or to be absorbed from capillaries within episcleral and subconjunctival tissue and join the systemic circulation.
INDICATIONS FOR TRABECULECTOMY
For most ophthalmic surgeons, the indications are as follows: a patient with glaucoma on maximum-tolerable medical therapy who has achieved maximal laser benefit and whose optic nerve function is failing or is likely to fail.
The surgeon must be certain the patient has glaucoma, and not just ocular hypertension or nonglaucomatous optic neuropathy. This determination implies characteristic damage to the optic nerve, visual field, or both.
SURGICAL TECHNIQUE
Trabeculectomy is, in essence, a filtering procedure designed to divert the aqueous humor through an eye-wall fistula (hole) to a subconjunctival filtering reservoir, the filtering bleb. The goal of glaucoma filtering surgery, as with medical and most laser therapies, is to lower intraocular pressure (IOP) below the threshold that causes optic nerve damage.
THE ROLE OF ANTI-METABOLITES
The use of anti-metabolites during filtration surgery has greatly enhanced surgical success rates in high-risk eyes. These chemicals are applied to the eye during surgery. They help reduce scarring of the surgically created wound. This allows the newly created glaucoma drain to remain open. Unfortunately, they are not without a significant downside. They have been shown to increase the rate of post-operative infection. In addition, they increase the incidence of postoperative wound leakage. Intra-operative or post-operative use of 5-fluorouracil (5-FU) or mitomycin C (MMC), to limit scarring following glaucoma filtering surgery, can improve the surgical outcome of an eye with a poor prognosis.
RISKS OF TRABECULECTOMY
The risks of glaucoma surgery include bleeding, infection, blindness, and loss of the eye. These risks are not unique to glaucoma surgery. However, eyes with glaucoma are usually “sicker” than eyes without glaucoma. Despite these risks, the benefits of long-term pressure reduction are great. Numerous scientific studies have repeatedly demonstrated that patients whose pressures are lowered by at least 30% from their untreated levels have better preservation of visual function over the course of their lifetime.
POST-OPERATIVE COURSE
Glaucoma surgery aims to lower intraocular pressure without the use of glaucoma medications. During the early postoperative period, the intraocular pressure can be variable. In some patients, the pressure is quite low. In other patients, postoperative pressure may be higher than preoperative pressure.
When pressure fluctuates, a patient’s vision often does too. Patients often experience blurred and frankly poor vision for the first 6 weeks after surgery. Fortunately, by the beginning of the second month following surgery, vision usually returns to its preoperative level and stays there. One of the paramount goals of glaucoma surgery is to minimize an individual’s dependence on glaucoma medication. Although this is not achieved in 100% of cases, it is certainly attainable in a good number. The following pages illustrate and describe a surgical trabeculectomy.
POST-OPERATIVE PATIENT INFORMATION
TRABECULECTOMY SURGERY
1. TRABECULECTOMY lowers the pressure inside the eye! They do not cause the fluid to drain into your tears. The fluid, which is drained out of your eye, is shunted to the back of the eye, and from there it enters the venous system to be removed from the eye as it mixes into the bloodstream.
2. BLURRY VISION IS NORMAL AFTER THIS SURGERY
Your vision will be very blurry for the first 3 to 6 weeks following this surgery. Many patients become anxious during the first month after surgery because their vision does not return to normal immediately after surgery. I cannot over-emphasize that it is normal to have very blurry vision for 6 full weeks following the surgery. It is important to keep this in mind so as not to become worried that something has gone wrong with your surgery.
3. WATERING OF THE EYE IS NORMAL AFTER SURGERY
Tearing, watering, and mattering are all common complaints after this type of surgery. The excessive tearing and watering will resolve on their own over the first 3 to 6 weeks. It is not a permanent problem. Be patient, this problem is very common but always resolves spontaneously over time.
4. A SCRATCHY OR “SANDY” SENSATION IS NORMAL AFTER SURGERY
Glaucoma surgery requires stitches (sutures). The stitches dissolve spontaneously. It takes about 3 to 6 weeks for the stitches to dissolve. During this period, you may feel a stitch in the eye. This is NORMAL! Some people feel this scratchy sensation a few days after surgery; some do not experience it until many weeks after surgery. Do not be alarmed if you experience this. One way to lessen discomfort is to use an eye ointment, which your doctor can prescribe in the office or call in to your pharmacy. There are also over-the-counter ointments available, which your doctor may recommend. The ointments lubricate the stitches and minimize the friction between the stitches and your eyelids. The ointments help relieve eye discomfort but can cause blurry vision because they are very thick. They are very helpful if used before going to sleep because they have minimal effect on your vision and help keep your eyes moist while you sleep. They might cause your eye to stick shut in the morning, but this can be easily relieved with a cool compress.
5. YOU WILL NOTICE A CYST ON THE UPPER PART OF YOUR EYE
This cyst is called a “bleb.” This is a normal occurrence. In fact, we hope to have a good-sized bleb because this is where your new drain is. The bleb often looks like a blister. Do not be alarmed if you see it. It is supposed to be there!
6. SEVERE PAIN, HEADACHE, AND NAUSEA ARE NOT NORMAL
MUCUS, PUS, OR GREEN-YELLOW DISCHARGE IS NOT NORMAL.
If you experience any of these, please call our office immediately at (602) 955 -1000.
GLAUCOMA SURGERY-GLAUCOMA DRAINAGE DEVICES (GDD) OR AQUEOUS SHUNTS
During the past two decades, glaucoma drainage devices (GDDs) have been increasingly used in the treatment of glaucoma. Approximately 5000 GDDs are used in the United States annually. Most GDDs consist of a segment of silicone rubber tubing attached to a rigid plastic or flexible silicone rubber explant.
As previously discussed, glaucoma occurs when intraocular pressure rises. The pressure usually rises due to damage to the eye’s natural drainage system. GDD’s work by “shunting” excess fluid out of the eye through the silicone rubber tubing. Once removed from the eye, the fluid joins with venous blood, which is returned to the heart
Over the past 5 years, the use of GDDs has grown rapidly. This increase is due to both improved devices and improved surgical techniques.
GDDs are less prone to failure than traditional “trabeculectomy” because they are less affected by post-surgical scarring. An important advantage of GDDs over trabeculectomy is that they do not leave the eye as susceptible to infection following otherwise successful surgery.
The first GDD was the Malteno glaucoma implant, which initially appeared in 1969. Commercially manufactured GDD’s currently available in the U.S., including both “valved” or “flow-restricted” designs (Ahmed, Krupin) and “nonvalved” (Malteno, Baerveldt) designs. While differing in size, shape, and installation details, all of these devices share common features and utilize the same physiologic principles.
GLAUCOMA SURGERY-GLAUCOMA DRAINAGE DEVICES
HOW TO GDDs WORK?
The human eye produces a clear, watery fluid called aqueous humor. In a healthy individual, this fluid is drained from the eye at the same rate at which it is produced. In patients with glaucoma, the eye loses its ability to drain fluid as quickly as it is produced. As a consequence, the aqueous humor accumulates in the eye, and the pressure within the eye increases. The increase in pressure damages structures within the eye. The structure within the eye that is most susceptible to increased pressure is the optic nerve. Thus, glaucoma is defined as damage to the optic nerve resulting from increased intraocular pressure.
As we have discussed, patients with glaucoma usually have a damaged drainage system. GDDs’s lower pressure because they allow the excess fluid to bypass the damaged drainage system. GDD’s work by “shunting” fluid out of the eye. They consist of a one-way drain attached to a straw-like tube. The drain is called the “plate.” The tubing is surgically inserted into the eye. It runs from the inside of the eye to the plate, which is sutured to the outside of the eye. Thus, aqueous humor is shunted from inside the eye to the plate, where it is absorbed by blood vessels, which return it to the systemic circulation.
INDICATIONS
The general indications for installing GDDs include failure of conventional therapies such as medications, laser trabeculoplasty, and standard trabeculectomy with or without antifibrotic agents.
GLAUCOMA SURGERY-GLAUCOMA DRAINAGE DEVICES
POST-OPERATIVE COURSE
GDDs, as do some trabeculectomies, have demonstrated a period of elevated pressure before the ultimate lowering occurs. Intraocular pressure often initially falls, then rises to preoperative levels or even higher for weeks before falling again. Resumption of medications is indicated to minimize the transient pressure rise.
POST-OPERATIVE MEDICATIONS
Post-operative medications following GDD surgery include topical corticosteroids such as Pred Forte 1% from 4 to 6 times a day. In addition, topical antibiotic (Ciloxan, Oxuflox) drops should be used. Glaucoma medications will usually need to be resumed promptly after placement of a GDD, pending spontaneous or surgical opening of the tube as the absorbable ligature dissolves or is cut with a laser
WHAT ARE THE MOST COMMON COMPLICATIONS?
Complication rates for GDDs have fallen drastically over the past decade due to improved knowledge and experience with the devices. In general, the most common complications of ocular surgery are bleeding or infection, which, in the worst-case scenario, can lead to total blindness and loss of the eye. The most common short-term complication is low pressure. The major long-term problems seen with GDDs are double vision and corneal decompensation. The reasons for double vision are varied and not always predictable. Corneal decompensation occurs when the tube migrates and contacts the inner corneal surface. Both of these problems can be surgically remedied. Double vision can be remedied by removing the GDD. Corneal decompensation can be improved by corneal transplantation.
SUMMARY
In summary, GDDs offer an excellent alternative to conventional filtration surgery. Surgery should be performed by a surgeon with broad experience with GDDs. Once functioning, GDDs can provide good long-term intraocular pressure reduction and glaucoma control. Unfortunately, as with all glaucoma procedures, the pressure control provided by these devices is not always permanent. However, GDDs offer the most predictable long-term pressure control for glaucoma patients.
GLAUCOMA SURGERY-GLAUCOMA DRAINAGE DEVICES
SURGICAL TECHNIQUE
The white part of the eye is called the sclera. The sclera is covered by a thin, film-like layer of clear tissue called the conjunctiva. Surgery involves opening the conjunctiva, thereby exposing the sclera. The drainage device is then placed in a selected quadrant and sutured to the sclera. The tube is then inserted into the eye through a tract created by a small needle. The tube is then temporarily closed off with an absorbable suture and anchored to the sclera. The tube is then covered with a piece of donor sclera or pericardium. The conjunctiva is then closed in a watertight fashion, completely covering the drainage device and the tube.
POST-OPERATIVE PATIENT INFORMATION
from ANDREW RABINOWITZ, M.D.
1. GLAUCOMA DRAINAGE DEVICES
Lower the pressure inside the eye!. They do not cause the fluid to drain into your tears. The fluid, which is drained out of your eye, is shunted to the back of the eye, and from there it enters the venous system to be removed from the eye as it mixes into the bloodstream.
2. DOUBLE VISION IS NORMAL AFTER THIS SURGERY
It is not unusual to experience double or triple vision after this type of surgery.
Double vision is usually worse during the first 3 weeks, then slowly improves over the first 3 months. Many patients become alarmed when they experience double vision, but I stress that this is a normal occurrence and does not indicate anything has gone wrong with your surgery. Some people find that patching the eye for a few weeks makes the double vision go away. There is no harm in covering the operated eye during the daytime to reduce double vision. I often recommend this to patients who experience double vision.
3. WATERING OF THE EYE IS NORMAL AFTER SURGERY
Tearing, watering, and mattering are all common complaints after this type of surgery. Excessive tearing and watering will resolve on their own over the first 3 to 6 weeks. It is not a permanent problem. Be patient; this problem is very common and always resolves spontaneously over time.
4. BLURRY VISION IS NORMAL AFTER THIS SURGERY
Your vision will be very blurry for the first 3 to 6 weeks following this surgery. Many patients become anxious during the first month after surgery because their vision does not return to normal rapidly. I cannot over-emphasize that it is normal to have very blurry vision for 6 full weeks following the surgery. It is important to keep this in mind so as not to become worried that something has gone wrong with your surgery.
5. IT TAKES 6 WEEKS BEFORE THE SHUNT LOWERS EYE PRESSURE
The drainage device controls pressure by shunting fluid out of the eye. The device, however, is designed to gradually lower pressure over 6 weeks following surgery. In fact, the drain does not work at all for the first month after surgery. After that time, it slowly drains the fluid and lowers the pressure. By six weeks after surgery, the drain will be working at full capacity.
6. SEVERE PAIN, HEADACHE, AND NAUSEA ARE NOT NORMAL
If you experience any of these, please call our office immediately at (602)=955-1000.
DEEP SCLERECTOMY WITH VISCOCANALOSTOMY (DSVC)
The most commonly performed glaucoma procedure in the United States is the trabeculectomy. Trabeculectomy attempts to make a partial hole in the white part of the eye (sclera). Aqueous humor drains through this hole into a small blister-like cyst known as the “bleb.” Unfortunately, the bleb formed after successful glaucoma surgery has several unfavorable characteristics. Firstly, the bleb may be elevated, leading the patient to feel as though something is in their eye. Secondly, large blebs can grow onto the cornea and become cosmetically unacceptable. Finally, blebs make the eye susceptible to severe infections. The risk of developing a severe infection leading to blindness is much greater in eyes with functioning blebs.
Glaucoma surgeons have spent the past decade attempting to invent a glaucoma surgery that does not result in the creation of a bleb. DSVC attempts to bypass the obstructed trabecular meshwork without creating a scleral hole or fistula. DSVC is referred to as non-penetrating filtration because no hole is created in the eye as is done with trabeculectomy.
DSVC involves creating a drainage channel without forming a full-thickness hole in the sclera. Theoretically, this will greatly decrease the incidence of post-operative wound leaks and infections. In addition, because no hole is made, the surgery is less susceptible to failure, as scarring is less critical to its long-term success.
DSVC is a surgery in its infancy. The results of our initial experience with DSVC are encouraging enough to stimulate significant worldwide interest in this procedure.
I have performed over 200 of these procedures with promising results. The rate of postoperative complications has been lower than that seen with trabeculectomy. Bleb formation does occur in about 25% of cases. These blebs, however, are low-lying and usually disappear by 6 months. The intraocular pressure has remained controlled even in
cases in which the bleb becomes extinct.
DSVC will not completely replace conventional filtration surgery. However, it will likely assume a crucial role as an alternative to trabeculectomy. DSVC may, in fact, become the treatment of choice in juvenile glaucomas, pigmentary glaucomas, and open-angle glaucomas in myopic eyes. Results of DSVC have been less favorable in far-sighted patients and eyes with inflammatory glaucomas.
Further studies and refinement of the technique will undoubtedly push the envelope of glaucoma surgery. DSVC offers an excellent alternative to trabeculectomy. This is important in patients who have undergone unsuccessful trabeculectomy in one eye and require initial surgery in the fellow eye.
In glaucoma, hope springs eternal. Clinical trials are underway for another novel glaucoma surgery that uses a synthetic “wick” to draw aqueous fluid out of the eye through a non-penetrating scleral reservoir. We hope to participate in this international clinical trial in the coming months. This would enable The Barnet Dulaney Eye Center to offer cutting-edge glaucoma surgical treatment.
POST-OPERATIVE PATIENT INFORMATION
DEEP SCLERECTOMY SURGERY
1. DEEP SCLERECTOMY
Lowers the pressure inside the eye. The fluid, which is drained out of your eye, is shunted to the back of the eye, and from there it enters the venous system to be removed from the eye as it mixes into the bloodstream. The fluid removed from your eye does not join with your tears.
2. BLURRY VISION IS NORMAL AFTER THIS SURGERY
Your vision will be very blurry for the first 3 to 6 weeks following this surgery. Many patients become anxious during the first month after surgery because their vision does not return to normal rapidly. I cannot over-emphasize that it is normal to have very blurry vision for 6 full weeks following the surgery. It is important to keep this in mind so as not to become worried that something has gone wrong with your surgery.
3. WATERING OF THE EYE IS NORMAL AFTER SURGERY
Tearing, watering, and mattering are all common complaints after this type of surgery. Excessive tearing and watering will resolve on their own over the first 3 to 6 weeks. It is not a permanent problem. Be patient; this problem is very common and always resolves spontaneously over time.
4. A SCRATCHY OR “SANDY” SENSATION IS NORMAL AFTER SURGERY
Glaucoma surgery requires stitches (sutures). The stitches are self-absorbing. It takes about 3 to 6 weeks for the stitches to dissolve. During this period, you may feel a stitch in the eye. This is NORMAL! Some people feel this scratchy sensation a few days after surgery; some do not experience it until many weeks after surgery. Do not be alarmed if you experience this. One way to lessen discomfort is to use an eye ointment, which your doctor can prescribe in the office or call in to your pharmacy. There are also over-the-counter ointments available, which your doctor may recommend. The ointments lubricate the stitches and minimize the friction between the stitches and your eyelids. The ointments help relieve eye discomfort but can cause blurry vision because they are very thick. They are very helpful if used before going to sleep because they have minimal effect on your vision and help keep your eyes moist during sleep. They might cause your eye to stick shut in the morning, but this can be easily relieved with a cool compress.
5. YOU WILL NOTICE A CYST ON THE UPPER PART OF YOUR EYE
This cyst is called a “bleb.” This is a normal occurrence. The bleb often looks like a blister. Do not be alarmed if you see it. It is supposed to be there!
6. SEVERE PAIN, HEADACHE, AND NAUSEA ARE NOT NORMAL
MUCUS, PUS, OR GREEN-YELLOW DISCHARGE IS NOT NORMAL.
If you experience any of these, please call our office immediately at (602) 955 -1000.
TRANS-SCLERAL LASER CYCLOPHOTOCOAGULATION (CPC)
WHAT IS CPC?
The ciliary body is the structure that produces aqueous humor. Aqueous humor is a clear liquid. This liquid is responsible for maintaining the shape of the eye. Cyclodestruction is a treatment that destroys cells of the ciliary body. In so doing, the treatment aims to shut down fluid production in the eye. Cyclodestructive procedures are recommended in patients with advanced glaucomas and otherwise poor prognoses. Often, these patients have been relative failures of medical therapy and glaucoma filtering surgery. In many respects, CPC can be viewed as a “last-step effort to save the eye.”
Cyclodestructive procedures are also useful in patients in whom conventional surgery is contraindicated by systemic health or local ocular conditions. Generally, these patients have little or no functional vision. Reduction of intraocular induced pain in this clinical setting is an important indication.
WHO IS A CANDIDATE FOR CPC?
CPC is reserved for patients who have undergone multiple eye surgeries, including glaucoma surgeries, and who still have elevated eye pressure. Often, these patients have lost a significant amount, if not all, of their vision
WHAT ARE THE INDICATIONS FOR THIS PROCEDURE?
1. Persistently elevated eye pressure despite aggressive surgical treatment.
2. A painful eye with little or no sight remaining.
3. Uncontrolled glaucoma in a patient who is not a good surgical candidate.
4. Reduction of pain in a blind eye.
HOW DOES THE LASER GET TO THE EYE?
The laser energy is delivered to the eye via a probe that resembles a pen.
The entire procedure usually takes 2 to 5 minutes. The procedure is well tolerated because the patient is pre-treated with a local anesthetic. The treatment does not require any incisions, sutures, or needles.
WHAT IS THE SUCCESS RATE OF CPC?
The results of CPC are generally quite good. Most patients can be successfully treated with one to two sessions of laser therapy. In severe glaucomas, the treatment may have to be repeated two to three times over the first year to obtain maximum pressure control. One of the greatest advantages of the procedure is that it can be repeated as often as is needed.
WHAT ARE THE MAIN RISKS?
The most significant risk with this procedure is that the eye pressure becomes too low and stays that way. This is a very rare occurrence and is often not a problem, as pain control is usually the main indication for this procedure. Like other eye surgeries, bleeding and infection are very low, but possible risks.