In order to preserve eyesight, it is critical to decrease and control the elevated intraocular pressure (IOP) associated with glaucoma. Depending on your individual situation, there are several treatment options available:
Mild-Moderate Glaucoma
Medication (eye drops) is the most common form of treatment for glaucoma; however, there are side effects, and medication is not effective for all patients – and you have to remember to take your medication every day. There are a number of different types of eye drops, but all are used to either decrease the amount of fluid (aqueous humor) in the eye or to improve the outflow of this fluid in order to stabilize or reduce IOP. Your doctor will decide which medication is best suited to you based on a number of considerations, including: medical history and current medication regimen. Your doctor may also elect to prescribe a combination of eye drops.
Canaloplasty is a minimally invasive glaucoma surgery (MIGS). Unlike other MIGS procedures, which bypass the natural outflow pathway, canaloplasty is unique in that it acts to reestablish the function of the eye’s natural drainage system. By addressing all aspects of outflow resistance, including the trabecular meshwork, Schlemm’s canal and the collector channel system, canaloplasty is able to deliver an average reduction in eye pressure of 30%.
How is canaloplasty performed?
First, your doctor will make a small incision in the eye. A microcatheter designed specifically for canaloplasty is then inserted into the eye’s drainage canal. Your doctor will advance the microcatheter 360 degrees around the canal to open up the channel and enlarge it. Once the end of the catheter has circumnavigated to its point of entry, the microcatheter tip is slowly pulled back while sterile, viscoelastic gel is injected into the canal to dilate it to 2 – 3 times its normal size. The microcatheter is then removed from the eye. It is important to note that there are no permanent implants or devices left in the eye.
Canaloplasty can be performed during cataract surgery, or as a stand-alone procedure. Your doctor will be able to determine which option is best for you.
SLT or Selective Laser Trabeculoplasty, is a low-energy laser therapy, which triggers a natural healing response in the eye in order to reduce the IOP associated with glaucoma. SLT effectively lowers eye pressure in the majority of patients, but the length of time that pressure remains low depends on many factors, including: age of the patient, the type of glaucoma, and other medical conditions that may be present. In many cases medication may still be necessary, but in reduced amounts.
Note: Previously, Argon Laser Trabeculoplasty (ALT) was used to treat glaucoma. ALT uses a high-energy laser to ‘open’ the clogged areas of the trabecular meshwork (the eye’s drainage system), allowing fluid to bypass this drainage system and flow out of the eye. However, unlike SLT, ALT causes permanent coagulative damage to the eye and cannot be repeated.
How is SLT performed?
SLT treatment takes just a few minutes to perform. Prior to treatment, your doctor will administer eye drops in order to prepare the eye and provide mild anesthesia. Then, gentle pulses of SLT laser light are delivered through a specially designed microscope, known as a slit lamp. The entire process takes just a few minutes. Once complete, your doctor may treat your eye with anti-inflammatory eye drops. One to three days after the procedure, your IOP should drop significantly. And of course, your doctor will want to re-check the treated eye during periodic follow-up visits.
Severe Glaucoma
Canaloplasty can be performed via an ab-externo surgical technique for cases of severe glaucoma. It uses breakthrough microcatheter technology, similar to angioplasty, to enlarge your eye’s natural drainage system. Importantly, canaloplasty has been shown to be less invasive than traditional surgical treatments.
How is canaloplasty performed?
First, your doctor will make a small incision in the eye. The advanced Canaloplasty microcatheter will be inserted into the eye’s drainage system canal. Using the microcatheter, your doctor will circle the canal and enlarge it via visco-dilation, which will help the aqueous fluid drain properly. The microcatheter is then removed and a suture is placed within the canal to keep it open. By restoring your eye’s natural drainage system, the pressure inside your eye is usually lowered. Canaloplasty can also be performed when other surgeries have failed (even those offered for late-stage disease) and with a very good success rate. Canaloplasty is an outpatient procedure and is performed by your ophthalmologist, but may require an overnight stay in hospital.
Late-Stage Glaucoma
During the Molteno3® surgery, a small drainage device is implanted in your eye. This device consists of a small plate and a tube. The tube creates a new drainage channel through which the eye’s fluid can flow from the front chamber of the eye to a filtering area called a bleb. The Molteno3® glaucoma drainage device is placed outside the eye but is covered by the skin of the eye and thus it cannot be seen or felt.
Molteno3® surgery is an outpatient procedure and is performed by your ophthalmologist, but may require an overnight stay in hospital. The total procedure takes about 60 – 90 minutes. Postoperatively, you will need to take eye drops and/or pain medication. Regular follow-up examinations with your ophthalmologist will track the pressure changes in your eye and ensure that the Molteno3® glaucoma drainage device is working correctly. Potential side effects include blurred vision, bleeding in the eye, infection and discomfort.
During trabeculectomy surgery, your ophthalmologist will cut a flap in the white part of the eye (known as the sclera) and remove a piece of trabecular meshwork, which is the eye’s drainage channel. This creates a new opening through which the eye’s fluid can drain into a space under the skin around the eye (known as the conjunctiva) to form a ‘drainage bleb’. The drainage bleb sits under the upper eyelid. Potential side effects include blurred vision, bleeding in the eye, infection and discomfort.
Frequently Asked Questions
In a healthy eye, aqueous humor (fluid) is produced to nourish and clean the eye at the same rate at which it is drained in order to maintain a constant and normal intraocular pressure (IOP). A loss of drainage function leads to a high IOP, which can result in glaucoma. If left untreated, glaucoma can result in irreversible vision loss.
To date there is no cure for glaucoma. Glaucoma treatments are designed to slow, or halt, the progression of the disease. Your surgeon will determine what level of IOP is required in order to preserve your vision.
Many people with glaucoma cannot drive a car safely, see their grandchildren on the soccer field, and view the world as they once did. The first sign of glaucoma is often the loss of peripheral or side vision.
Typically, glaucoma is treated with a laser or with one or a combination of medications. However, drugs must be taken every day, and these medications can lose their effectiveness over time, especially when patients are in the advanced stages of the disease. When medications cease to be effective, or are deemed unsuitable due to side effects or lifestyle, different surgical techniques can be used.
Canaloplasty is an advanced surgical treatment for glaucoma. It uses breakthrough microcatheter technology to enlarge your eye’s natural drainage system, similar to angioplasty.
Canaloplasty works within the natural structures of the eye. No artificial pathways are created, and no incisions are made within the visual field of the eye. There is a reduced level of postoperative complications when compared to traditional surgical techniques.
Canaloplasty is an effective surgical option for the majority of glaucoma patients, including: open-angle glaucoma (OAG), pigmentary glaucoma (PG), pseudoexfoliation glaucoma (PXF), normal tension glaucoma (NTG) and juvenile glaucoma. It is also suitable for patients who wear contact lenses. Patients with contact lenses are unable to undergo the traditional forms of glaucoma surgery (trabeculectomy or shunt). Canaloplasty is well suited to patients at high risk for infection or bleeding and those with enhanced wound healing. Canaloplasty may also be suited to patients who have had complications in the other eye following trabeculectomy.
Various studies have demonstrated the ability of canaloplasty to significantly reduce intraocular pressure (IOP). As an added benefit, many patients who undergo canaloplasty no longer require anti-glaucoma medications, or can reduce the number of medications required.
Traditional glaucoma surgeries (trabeculectomy or shunt surgery) require the creation of a permanent hole (or fistula) through the wall of the eye (sclera). In contrast, canaloplasty works independent of a fistula. As a result, canaloplasty has been shown to offer a much better risk-benefit ratio and requires minimal post-operative follow-up: patients can return to normal day-to-day activities almost immediately following treatment.
First, your surgeon will make a small incision in the eye. A microcatheter designed specifically for canaloplasty is then inserted into the eye’s circumferential drainage canal, which may be reduced in size or closed due to the high pressure in your eye. Your surgeon will advance the microcatheter 360 degrees around the canal to open up the channel and enlarge it. Once the end of the catheter has circumnavigated to its point of entry, the microcatheter tip is slowly pulled back while sterile, viscoelastic gel is injected into the canal to dilate it to 2 – 3 times its normal size. Enlarging and flushing through the drainage canal and adjacent outflow channels helps the aqueous fluid to drain properly. The microcatheter is then withdrawn from the eye. It is important to note that there are no permanent implants or devices left in the eye.
By restoring your eye’s natural drainage system, the pressure inside your eye is usually lowered.
One to three days after the procedure, your intraocular pressure should drop significantly. And of course, your physician will want to re-check the treated eye during periodic follow-up visits.
Depending on the results of the procedure, your ensuing intraocular pressure (IOP) and the severity of your glaucoma, your surgeon will evaluate whether or not you need to continue to use any medication.
Canaloplasty is a minimally invasive glaucoma surgery and offers a high safety profile with limited risk of complications and side effects. It is important to note, however, that all surgeries have risks associated with them. The most common side effects associated with canaloplasty are bleeding in the eye and IOP spikes.
During the canaloplasty procedure, “viscoelastic” refers to a sterile, gel-like material, which is injected into the canal to dilate the drainage channel, thereby facilitating the exit of fluid through the natural outflow pathways.
There is growing evidence that Schlemm’s canal (the eye’s natural drainage duct) decreases in size with long-term use of anti-glaucoma medications. If there is significant stenosis (scarring down) of the canal, then it may not be possible to pass the microcatheter all of the way around the canal. However, even if your ophthalmologists cannot circumnavigate the entire 360 degrees of the canal, it is generally possible to dilate a significant portion of the canal with viscoelastic in order to provide an IOP-lowering effect.
Canaloplasty can be performed after SLT. And SLT can also be performed after canaloplasty. The two treatments are considered to be complementary given that they both stimulate the natural outflow systems, by biological and surgical means respectively.
A key benefit of canaloplasty is that is does not preclude other forms of glaucoma surgery. If the procedure is unsuccessful, your surgeon may elect to perform conventional glaucoma surgery (trabeculectomy).
PhacoCanaloplasty is a combined cataract and glaucoma treatment. During the first part of the procedure, your surgeon will replace the clouded natural lens of your eye with an artificial lens in order to help give you sharper vision. In the second part of the procedure your surgeon will use microcatheter technology to enlarge your eye’s drainage system, similar to angioplasty, in order to reduce your intraocular pressure (IOP).
While traditional glaucoma surgeries can be effective, they permanently impact the anatomic structure of the eye and can require repeated, unscheduled visits to the ophthalmologist for wound management. Canaloplasty is a restorative treatment. Unlike trabeculectomy, which bypasses the eye’s natural drainage channels, canaloplasty aims to restore the natural outflow pathways in order to reduce the elevated intraocular pressure associated with glaucoma. Canaloplasty works within the natural structures of the eye because no artificial pathways are created and no incisions are made within the visual field of the eye. Canaloplasty has a high safety profile and requires minimal post-operative follow-up: canaloplasty patients can return to normal day-to-day activities almost immediately following treatment.
During trabeculectomy, your surgeon will create a hole in the wall of the eye (sclera) to allow the fluid to flow from the inside of the front of the eye (anterior chamber) through the scleral hole to a bleb (cyst, or blister-like elevation of the conjunctiva). Trabeculectomy is a highly invasive technique that bypasses the eye’s natural outflow pathways and carries a high risk of complications such as infection and leakage. In contrast, canaloplasty is a less invasive technique which uses breakthrough microcatheter technology to enlarge your eye’s natural drainage system, improving outflow and lowering eye pressure. It is important to note that canaloplasty acts to restore the natural outflow system, rather than bypass it. And canaloplasty does not leave any permanent implant or device in your eye.
Canaloplasty is essentially a modification of viscocanalostomy, which was first described in 1991 by South African glaucoma specialist Dr. Robert Stegmann. The iTrack™ canaloplasty microcatheter was cleared by the FDA more than 10 years ago. To date, more than 100,000 iTrack™ procedures have been performed worldwide.
With traditional ab-externo canaloplasty, the microcatheter is inserted from an external approach i.e. ab-externo: cutting through the conjuctiva and sclera. With ab-interno canaloplasty, the microcatheter is inserted from an internal approach i.e ab-interno: through either a clear corneal or a limbal micro-incision, then through a small opening in the trabecular meshwork, and into Schlemm’s canal.
Unlike the ab-interno surgical, which combines a process of catheterization and viscodilation to simply enlarge Schlemm’s canal to 2 – 3 times its normal size, thereby restoring the outflow of aqueous fluid, ab-externo canaloplasty requires several additional surgical steps. For example, a surgical procedure called deep sclerectomy, whereby two flaps are cut into the sclera to expose and access the Schlemm’s canal, must first be performed. The ab-externo surgical technique also uses a tensioning suture to help ensure a sustained reduction in IOP.
The ab-interno surical technique is well suited to patients suffering from glaucoma in its early stages and can be easily combined with cataract surgery to reduce IOP and/or your reliance on medications. The ab-externo surgical technique s a more viable option if you suffer from glaucoma in its later stages and thereby require a more significant reduction in IOP.