Glaucoma is a term that is used to describe a broad range of eye problems that can damage the optic nerve and cause loss of vision. The pressure inside the eye, called Intraocular Pressure (IOP), generally falls within a range that is considered “normal”. Many patients believe that Glaucoma is simply due to a high pressure within the eye. While a high Intraocular pressure can be one cause of Glaucoma, and in fact is the most common cause of Glaucoma, a high IOP may not be the only cause of Glaucoma. There are a number of possible causes of Glaucoma. Regardless of the cause, the various types of Glaucoma share a common factor-if not diagnosed early, treated properly and controlled, it will result in permanent vision loss and potentially blindness.
Glaucoma is a very complex eye disease and not simply an elevated Intraocular Pressure (IOP). Nonetheless, when detected early it can be successfully treated. Dr. Spector is a Fellowship trained Glaucoma specialist and provides comprehensive diagnostic testing and treatment for Glaucoma as well as taking the time necessary to give each patient the personal education needed to fully understand their condition.
The best way to maintain eye health and preserve your vision is to have regular and complete eye examinations with the appropriate level of diagnostic testing for Glaucoma as recommended by Dr. Spector. During your examination, Dr. Spector and the staff may perform a number of tests in order to make the most accurate diagnosis of Glaucoma.
These include the following testing procedures:
The Tonometry Test is a method of measuring your Intraocular Pressure (IOP). This test involves first placing some eye drops into your eyes to numb them and then lightly touching the surface of the Cornea with a specialized measuring instrument. There is no discomfort involved. The test is quick and gives Dr. Spector the first piece of important information in determining whether you have Glaucoma.
Ophthalmoscopy is a method of carefully examining the inside of the eye, especially the optic nerve in order to detect Glaucoma. Some eye drops will be placed in your eyes in order to dilate your pupils so that Dr. Spector can make a clear and direct observation of the optic nerve. The examination will take place in a darkened room using different types of Ophthalmoscopes in order to examine the shape and color of your optic nerve. If either the Intraocular Pressure (IOP) is elevated or the optic nerve appears unusual, additional tests will be necessary in order to complete the Glaucoma examination.
- Visual Field Perimetry
Perimetry or Visual Field testing is an important part of the Glaucoma examination. During this test you will be asked to sit in front of a large “bowl like” instrument and look directly straight ahead. A computer program will present a number of lights in different positions of their “side” or peripheral vision to see how sensitive your side vision is in various directions. The computer will then plot an actual map of the field of vision so that Dr. Spector can interpret this map in conjunction with other examination tests in order to understand how well the optic nerve is functioning. Glaucoma usually affects your side vision before your central vision, so visual field testing can often show any problems from glaucoma before you can notice them.
At Spector Eye Care, we use the most advanced computer imaging technology in order to make the earliest and most accurate diagnosis of Glaucoma. Our Optic Nerve Computer Imaging system is called OCT (Ocular Coherence Tomography). The OCT uses a method called “optical coherence tomography” that is capable of creating digital images through the use of special beams of light in order to create a contour map of the optic nerve and measure the retinal nerve fiber thickness. In many regards this is similar to the CT Scans used to study organ systems and tissues throughout your body.
The goal of OCT Optic Nerve Computer Imaging is to give Dr. Spector the ability to detect the slightest loss of optic nerve fibers, at the first possible moment, in order to diagnose Glaucoma at the earliest possible stage and stop the progression of the disease and preserve your vision. We perform OCT Optic Nerve Computer Imaging right in the comfort and convenience of our office.
- Pachymetry Measurement of Corneal Thickness
The National Eye Institute of the National Institutes of Health released a key study in 2002, called the Ocular Hypertension Study (OHTS). In this study an important finding was made regarding corneal thickness and its role in Intraocular Pressure and the development of Glaucoma.
The OHTS study found that corneal thickness is important because it can alter the accuracy of the measurement of Intraocular Pressure, potentially causing doctors to treat you for a condition that may not actually exist or to treat you unnecessarily when you are normal. Your actual Intraocular Pressure may be UNDERESTIMATED if you have thin corneas and it may be OVERESTIMATED if you have thicker corneas.
During a Glaucoma examination, Dr. Spector or a staff member may perform a Pachymetry Test to measure your corneal thickness as part of your examination and consider this finding in conjunction with the other Glaucoma testing in order to make the most accurate diagnosis.
The Pachymetry Test is a simple, quick and painless way of accurately measuring your coneal thickness that we do right in our office. The test is performed by first placing some drops in your eyes to make them numb and then lighty touching the cornea with a “pencil like” probe that uses sound waves to precisely measure your corneal thickness.
Everyone is at risk for Glaucoma. However, depending on your general health, eye health and other family history considerations, there are a number of factors that may influence your likelihood of developing Glaucoma. These “Glaucoma Risk Factors” are important to understand in assessing your own personal risk for developing Glaucoma. Glaucoma risk factors include the following:
- High Intraocular Pressure
A key warning sign of Glaucoma is having a higher than normal Intraocular Pressure (IOP). Anyone with an elevated Intraocular Pressure (IOP) is considered to be at risk for developing Glaucoma.
There is a direct relationship between age and the likelihood of developing Glaucoma. The chances of developing Glaucoma increase considerably after the age of 40. In fact you are six times more likely to get Glaucoma if you are over 60 years of age-even if you have no other family or medical history that is significant-and your risk is greater if you have any family history of Glaucoma or other systemic or eye disease that compromises your circulation such as diabetes.
Race plays a significant role in the likelihood of developing Glaucoma. African-Americans have certain genetic factors that cause a higher likelihood of developing Glaucoma. In fact they have a six to eight fold increase in risk for Glaucoma. Glaucoma is the leading cause of blindness in African-Americans. Asians appear to have higher risk for developing Narrow Angle Glaucoma. In addition, Hispanics over the age of 60 seem to be at increased risk as well.
Certain patients who are severely nearsighted have a higher risk of developing Glaucoma. This is believed to be due to extremely nearsighted eyes having anatomical features that can increase their risk of Glaucoma.
- Hypertension or High Blood Pressure
It is absolutely critical that patients who have hypertension or high blood pressure take their prescribed medication on a consistent basis. However, patients who take medication for high blood pressure may be at greater risk for Glaucoma as a result of the medication lowering the blood pressure and thus decreasing circulation within the optic nerve.
Diabetes can cause general problems with circulation throughout the body-including the eye. As a result of the poor circulation, patients with diabetes are considered to be at greater risk for developing Glaucoma due to these general circulation problems.
- Family History
Any family history of Glaucoma is considered a very significant risk factor. If any members of your family have been diagnosed with Glaucoma, it increases the likelihood that you will develop Glaucoma by 4-9 times over the general population. This is particularly true for siblings of Glaucoma patients who have a 5-fold increase in risk for developing Glaucoma.
- Other Glaucoma Risk Factors
In addition to these factors, if you have had trauma to your eyes (i.e. a sports injury or car accident) or if you have been treated for Asthma for long periods of time with steroid inhalers or have a corneal thickness less than .5mm, you too may have an increased risk for Glaucoma. Glaucoma is a very complex eye disease and not simply an elevated Intraocular Pressure (IOP). Nonetheless, when detected early it can be successfully treated.
As a Glaucoma Specialist, there are three main methods that Dr. Spector can use to treat Glaucoma: Medical, Laser or Surgical.
These treatment options for controlling Glaucoma are quite important, as Glaucoma has no cure. The good news is that in almost all cases, Glaucoma is treatable, but must be diagnosed as early as possible. Thanks to advances in Medical, Laser, and Surgery treatment for Glaucoma, Dr. Spector will be able to recommend an individual treatment plan that is best for each patient.
The following information is limited to treatment of Primary Open Angle Glaucoma, as it is the most common type of Glaucoma. Primary Open Angle Glaucoma is treated by the three different approaches above depending on the severity of the disease and the ability of each treatment option to slow or halt the disease progression and preserve your vision.
- Medical Treatment of Glaucoma
Primary Open Angle Glaucoma is most often treated with eye drops. There are many types of eye drops that can be prescribed to lower Intraocular Pressure (IOP). By using a single type of medication or sometimes 2 eye drops in combination, more than 80% of the patients with Open Angle Glaucoma can be successfully treated. These eye drops work by either decreasing the amount of fluid being produced inside your eye or by increasing the rate of drainage of fluid from your eye. For most patients, by using the eye drops as prescribed-1-2 times per day it is possible to control the Intraocular Pressure (IOP) and slow or even halt the loss of vision.
Unfortunately, some patients may experience side effects from these eye drops making the use of eye drops a poor treatment option. Also, some patients are unable to achieve adequate control with eye drops alone and require Laser Treatment for Glaucoma in addition to the eye drops in order to maintain control.
- Laser Treatment of Glaucoma
Dr. Spector has found that the use of Laser Treatment for Glaucoma has become an important treatment option for many patients. In the past, Laser Eye Surgery for Glaucoma was considered a “last resort” before Glaucoma Surgery. Today, thanks to advances in lasers, using a laser treatment for Glaucoma in conjunction with the eye drop treatment or sometimes even using the Laser Treatment as the primary treatment are excellent options to help maintain control and slow or stop the progression of the disease. Laser Treatment for Glaucoma is regularly used to help prevent vision loss and is becoming a Glaucoma treatment of choice for many patients who have problems with eye drops or are unable to use eye drops properly.
Argon Laser Trabeculoplasty (ALT) is a type of glaucoma laser treatment that helps to reduce the Intraocular Pressure (IOP) by creating more effective drainage of fluid through the Trabecular Meshwork. Unfortunately, for some patients, the effect of ALT decreases over time, rendering it ineffective. This is limiting, as ALT cannot usually be repeated.
Another type of Laser Treatment for Glaucoma that Dr. Spector can use is called Selective Laser Trabeculoplasty (SLT). SLT may offer advantages over ALT for some patients in that, should the effect decrease over time, SLT can be repeated several times in order to control the pressure and slow or halt the progression of the disease. SLT has promise in becoming an important treatment option not only for Glaucoma patients who are unable to use eye drops and obtain control, but as a primary treatment to help Glaucoma patients avoid needing to use eye drops altogether.
Dr. Spector routinely performs all types of Laser Eye Surgery for Glaucoma. If Laser Treatment is the best option to help control Glaucoma, he will spend the time necessary to explain the risks and benefits so that patients fully understand their treatment options.
- Surgical Treatment of Glaucoma
For a small number of patients, even with the maximum medical therapy they can achieve with Glaucoma eye drops and Laser Eye Surgery, it is still not possible to achieve good stable control of their disease and stop the progression of vision loss.
For these patients Dr. Spector can perform a number of surgical procedures to help achieve control of the Intraocular Pressure (IOP) and help to slow or stop the progression of the disease. These include removing a tiny piece of the Trabecular Meshwork, a surgical procedure called “Trabeculectomy”, “Sclerostomy” or “Filtering Procedure”, or even implanting a microscopic Glaucoma Valve to help reduce and stabilize the Intraocular Pressure (IOP) and prevent vision loss.
Types of Glaucoma
Glaucoma is a very complex eye disease and not simply an elevated Intraocular Pressure (IOP). Nonetheless, when detected early it can be successfully treated. As a Glaucoma Specialist, Dr. Spector provides all types medical, laser and surgical treatment of Glaucoma in order to help preserve vision.
- Open & Angle Closure Glaucoma
There are many types of Glaucoma. However, there are two main types of Glaucoma: Primary Open Angle Glaucoma (POAG), and Angle Closure Glaucoma. Sometimes it is possible to have damage to the optic nerve, even with a “normal” Intraocular Pressure (IOP). When optic nerve damage has occurred despite a normal IOP, this is called Normal Tension Glaucoma. Secondary Glaucoma refers to any case in which another disease causes or contributes to increased eye pressure, resulting in optic nerve damage and vision loss. Since Primary Open Angle Glaucoma and Angle Closure Glaucoma are the most common, we will limit our discussion to these types of Glaucoma.
- Primary Open Angle Glaucoma
The most common type of Glaucoma is Primary Open Angle Glaucoma (POAG). In the “normal” eye, there is a continuous production and drainage of a clear colorless fluid called “Aqueous Humor”. This production and drainage is balanced so that an equal amount is produced and drained in order to maintain an equilibrium, resulting in a “normal’ Intraocular Pressure (IOP). Patients with Primary Open Angle Glaucoma usually have an increase in Intraocular Pressure (IOP) upon routine measurement called Tonometry.
In the event that there is either too much Aqueous Humor being produced or too little Aqueous Humor is being drained there is a rise in pressure inside the eye. Any elevation of Intraocular Pressure (IOP) is considered “abnormal.” This elevation in pressure (IOP) causes the circulation in the optic nerve to become compromised, depriving it of oxygen and nutrients, resulting in permanent changes and even damage to the optic nerve. Any damage to the optic nerve can result in a loss of vision. The optic nerve is the connection responsible for communicating visual images between the retina and the brain. When the optic nerve is damaged, it is not able to carry visual images, resulting in vision loss. This is why it is so important to monitor, detect and control Intraocular Pressure (IOP). If left untreated, an elevated Intraocular Pressure (IOP) may, over time, cause slow, progressive and permanent damage to the optic nerve that can result in blindness. This is the nature of Primary Open Angle Glaucoma.
- Angle Closure Glaucoma
Angle Closure Glaucoma can be divided in two main types: Primary Angle Closure Glaucoma and Acute Angle Closure Glaucoma. Although Angle Closure Glaucoma occurs much less frequently than Open Angle Glaucoma, it is important to understand it because it has the ability to produce considerable vision loss in a short period of time.
Primary Angle Closure Glaucoma accounts for approximately 10% of all cases of Glaucoma and about 2/3 of these produce no symptoms for patients.
Acute Angle Closure Glaucoma is one of the only types of Glaucoma that produce distinct symptoms that include pain, light sensitivity, redness, blurred vision, colored haloes around lights and nausea or vomiting.
Angle Closure Glaucoma is characterized by a blockage or complete closure of the drainage structure of the eye called the Trabecular Meshwork. The Trabecular Meshwork is actually a fine filter. If it is blocked or obstructed by any alteration in the size or shape of the surrounding structures, or by change in the size or shape of the tissue itself, it will cause the Intraocular Pressure to elevate. In instances where the meshwork becomes blocked abruptly, it will cause a sudden rise in the Intraocular Pressure (IOP), resulting in Acute Angle Closure Glaucoma. Acute Angle Closure Glaucoma is characterized by this sudden rise in pressure which will can cause pain, redness, light sensitivity, colored haloes around lights, nausea or vomiting and blurred vision, and if left untreated permanent loss of vision.
Acute Angle Closure Glaucoma is considered a medical emergency. If you experience a sudden onset of pain, redness, blurred vision, light sensitivity, haloes around lights, nausea and vomiting, please call Spector Eye Care at 203.853.9900 and relay these symptoms to the receptionist so that you can be given an appointment immediately.
While there can be a several causes of Angle Closure Glaucoma, it is most often caused by anatomical changes within the internal structures of the eye. Angle Closure Glaucoma is considerably more common in farsighted eyes, which tend to be smaller and in patients between the ages of 45-60 years of age where the Crystalline Lens is beginning to swell.
During your routine eye exam if one of the eye doctors observes or measures a narrowed angle, he or she will perform an additional examination procedure called Gonioscopy. This will allow the doctor to directly examine the Trabecular Meshwork and the angle in order to carefully assess your predisposition to Angle Closure Glaucoma. By placing a special contact lens on your eye and then using the slit lamp biomicroscope to fully examine the meshwork and the angle with Gonioscopy the doctor will be able to make a thorough evaluation.