Measuring & Checking Eye Pressure By Finger Palpation
Checking eye pressure with fingers is not the most accurate way to check eye pressure, but in many situations, this is the best option available to your eye doctor. Let’s take a look at why doctors use their fingers in some cases to check eye pressure, and how checking eye pressure with fingers can be done.
Checking Eye Pressure With Fingers: Technique
The fingertip test is a non-invasive method that can be practiced on oneself or on your colleagues, with permission. This method relies on the examiner’s ability to gauge the pressure within the eye through gentle touch. It is considered useful when more accurate methods like Goldman Applanation or a Tonopen can not be used on the patient.
While it may lack the precision of other tonometry methods, the fingertip test still can provide valuable information. Especially in emergency settings associated with eye pain, this test can aid in detecting the potential presence of eye-related conditions.
The eye pressure measurement can be estimated as being soft or hard. Because the eye pressure measurement or IOP measurement is not going to be measured by a medical device, this is only an approximation of the eye pressure. The normal range of eye pressure ranges from 10 to 21, but this technique for checking eye pressure will not be able to provide a specific value in mm HG (millimeters of mercury).
Tpalp Soft
What does Tpalp soft mean? This is an abbreviation used by eye doctors to indicate that the eye is soft. T stands for tone or tonometry and palp stands for palpation. This is because the eye doctor will be using palpation to get an estimate of whether the patient has a normal IOP or a high IOP.
Tpalp Hard
Similar to how Tpalp soft indicates an eye with normal IOP, the abbreviation Tpalp Hard means that the eye pressure is high because the eye feels hard to the eye doctor.
What Is The Method For Checking Eye Pressure With Fingers?
Typically eye doctors will measure the eye pressure by using their pointer finger on each hand. They will ask the patient to close their eyes and then they will use the two fingers to alternate pressure on the eye ball. If they eye is easy to depress then this likely indicates a normal eye pressure.
However, it is very important to note that this is NOT an extremely accurate way to check for high eye pressure because this reading can not provide a number in millimeters of mercury.
What Are The Best Ways To Check Eye Pressure?
The best ways to check eye pressure are patient dependent. The methods mentioned below are preferred over checking eye pressure with fingers. Let’s take a look at why some patients may do better with certain methods.
Goldmann Applanation Tonometry
Using a Goldmann Applanation Tonometer is widely regarded as the gold standard for accurate measurements of eye pressure. Especially in glaucoma patients who are not stable, it is a good idea to recheck eye pressure with Goldmann Applanation Tonometry. This is sometimes also called the blue light test by patients.
In some cases, Goldmann may not be as useful as an Icare or a Tonopen. These are situations in which the patient has trouble staying still in the slit lamp machine. Or if they are wheelchair bound and straining to reach the slit lamp. Another situation is if the slit lamp is not accommodating to the patient’s body type. In these situations, it’s likely best to use one of the other methods to measure eye pressure.
Icare Tonometry
The iCare tonometer is unique because it can used in situations where other techniques can not. For example, you can use this device to measure eye pressure even if a patient has contact lenses on. Additionally, the use of this device does not need numbing drops.
The iCare can be especially useful in patients who can not tolerate drops or do not want drops. For pregnant patients or those who may be breastfeeding, they may want to avoid any additional medications. While proparacaine (medical name for the numbing drop) is very safe, this could be the patient’s preference. In this case, it is convenient to have an iCare available. If not, in the absence of any other eye disease, checking eye pressure with fingers can be acceptable in these cases.
Tonopen
The tonopen is a handheld device that can be used to check eye pressure. This is one of the oldest devices we have to check eye pressure. In some cases, where a patient’s body type prohibits them from getting an accurate eye pressure from the Goldmann Tonometer, the tonopen can be very useful. In patients who have good eye health and no medical history of other eye disease or their eye health is stable, this is a great device to use.
In many offices, tonopens are commonly used. This helps to improve the flow of the office, and allows the doctor to have all the data when the patient is ready to be seen. The healthcare provider or the eye technicians will first numb the eye using a drop of proparacaine. Then, they will gently touch the tip of the tonopen to the front of your eye. Although the tonopen does make direct contact with the front part of your eye, it does not hurt because your eye is numb from the numbing drop.
This eye pressure test can be done on patients who are unable to have Goldmann applanation testing.
In a patient who has a high intraocular pressure with a tonopen reading, it is a good idea to recheck the pressure. This pressure can be rechecked again with the same device, but in an ideal situation a different device is used to recheck the pressure. Eye pressure can fluctuate throughout the day. If a comprehensive eye exam reveals a high pressure, unless it is dangerously high, it is okay to wait a few days or a week or two and recheck it. If the eye pressure is dangerously eye then it may need to be treated and brought to a safe level
Do Doctors Still Use The Puff Of Air Method?
The air-puff tonometry method to check eye pressure is uncommonly used. Not only do patients dislike the air puff method, but it is also less accurate than some of the other techniques mentioned. This technique is falling out of favor with many eye doctors. This non-contact tonometry method, however, is more accurate than checking eye pressure with fingers because it will still provide the doctor with an actual number.
Which Patients Are Good Candidates For Checking Eye Pressure With Fingers?
As mentioned earlier, ideally doctors want a numerical value for the eye pressure. However, for many patients checking the pressure this way can be challenging.
Pediatric Patients
Not all pediatric patients can tolerate a pressure check with the tonometry test. In fact, unless it’s absolutely necessary, most very young patients will be assessed by checking eye pressure with fingers. For some patients who have suspicious looking optic nerves, doing a more accurate measurement to see if the patient has high pressure.
Patients Who Are Totally Blind
In some patients who are totally blind in both eyes but they are physically comfortable, a pressure check with palpation can be appropriate. This is because once the eye no longer has any vision, the intraocular pressure matters less. At this point in the patient’s journey, the eye doctor is most concerned with keeping the patient comfortable since there is no vision to preserve.
Patients Who Can’t Keep Their Eye Open
Some patients are unable to keep their eyes open. In this situation, the Goldmann applanation will not work and neither will the tonopen. The iCare will also be unable to be used in these patients as well as the air puff. These patients can be counseled on how to relax and they can be encouraged to take deep breaths to help them to remain calm during their pressure check. However, for some patients it is just not possible to check pressure using traditional methods during routine eye exams. In these patients, checking eye pressure with fingers is the only method eye doctors have.
In the uncommon case of angle-closure glaucoma, the patient may not be able to keep their eye open due to extreme pain. In these cases, checking the eye pressure with fingers may reveal an eye that is very hard. Other signs like red eye and pain can be helpful to determine if this is the cause. Although they may not be able to open their eye on their own, a doctor will likely need to help the patient to keep the eye open because getting an eye pressure reading in these cases is important. It is important not just for verifying the cause of the pain, but also for monitoring the progress of the IOP readings (intraocular pressure readings) as it is treated.
What Other Tests May Be Needed When Checking Eye Pressure With Fingers?
Because a specific value for eye pressure can not be obtained, it is always a good idea to get a view of the patient’s optic nerve. If the patient’s optic nerve is healthy, then it can provide some reassurance that their eye pressure is also in a normal range.
Visual Field Test
In the case of an optic nerve that appears unhealthy, or even slightly unhealthy, a visual field test can be very helpful in figuring out if this optic nerve appearance is from glaucoma or ocular hypertension. Vision loss from glaucoma can happen gradually, and early loss of peripheral vision from glaucoma is often unnoticed by patients. This test can help to catch the disease early.
Dilated Eye Exam
If the patient can tolerate a dilated eye exam, this is also a good idea. A dilated eye exam can not only help the eye doctor to see the optic nerve, but it can also help to evaluate for any other eye diseases. The risk of having other eye disease increase with age, so older adults should have dilated eye exams at regular intervals to ensure good vision later in life.
OCT (Optical Coherence Tomography)
An OCT is a special machine that helps the ophthalmologist to evaluate the health of the optic nerve on a microscopic level. This computerized test and imaging can provide fine details on the optic nerve’s structure. If there is thinning of the nerve, this could indicate nerve damage which could be from glaucoma.
The OCT is a great test because it can often pick up early stages of glaucoma before other testing. In addition, the OCT exam may show findings of glaucoma even when pressure readings are normal or the eye seems soft (Tpalp Soft as described above). OCTs and visual fields are often done together to determine the risk of glaucoma.
Pupillary Exam
A pupil exam is also important when eye pressure can not be checked. When one optic nerve is more damaged than the other optic nerve, the doctor may be able to see a pupillary abnormality. This is called an RAPD, which stands for Relative Afferent Pupillary Defect. This means that relative to the other eye, one optic nerve is more damaged. If both eyes are equally damaged, an RAPD may not be present since the finding is relative to the other side.
Visual Acuity Test
This is the most basic part of a complete eye exam. If there is a significant decrease in the vision in both eyes or a significant difference between the vision in each eye, this could indicate an issue that needs further work up. Your health care provider may need to do more tests such as the ones mentioned above in order to determine what the cause may be.
Corneal Thickness
Corneal thickness is commonly measured by a device called a pachymeter. Unfortunatley, if a patient is unable to have their pressure checked, it may also be unlikely that they are able to tolerate a pachymeter exam. Luckily, there are other machines that some eye doctors have to assess the thickness of the cornea. In patients who have thin corneas, higher eye pressures are more concerning. Thin corneas are a risk factor for glaucoma.
When Should Eye Pressure Not Be Checked Using Fingers?
In some cases, it is not a good idea to use fingers to check eye pressure. Let’s take a look at these specific situations.
After Eye Surgery
After a patient has cataract surgery or glaucoma surgery, eye pressure should not be checked with fingers. This is because it can cause unnecessary pressure on the surgical wound and cause low eye pressure. Once the post operative period is over and there is no risk of the wound being compromised, it is possible to use this method. However, it should only be done by someone who has a lot of experience in post surgical eyes. Additionally, if patients are having eye surgery, having an accurate pressure reading from Goldmann Tonometry or a Tonopen is more helpful from a clinical perspective.
After Eye Trauma
In the cases of eye trauma, checking eye pressure with fingers is not helpful and in some cases could be harmful. It is important to ask basic questions to the patient about the history and nature of the trauma. If there is a chance that the structure of the eye itself could be compromised (this is called a ruptured globe), then it is important to view the eye under a microscope first before attempting to check eye pressure.
During the slit lamp exam, it may become evident that the trauma has actually ruptured the eyeball. This means that there is full thickness violation in the structure of the eye itself. In these cases, no method of pressure checking is appropriate because it could cause further damage. In almost all of these cases, the patient will likely need to go to the operating room for evaluation, exploration and repair of the defect.
Checking eye pressure with fingers: Summary
Checking eye pressure with fingers can be done, but it is the least accurate way to check eye pressure (intraocular pressure or IOP). In some situations, it may be the only option that the doctor has. Other methods for checking eye pressure include Goldmann applanation, Tonopen, iCare Tonometer, and the Air Puff method. If there is any suspicion on the patient’s eye exam that there is an eye health issue, it is important to get supporting testing to help create as comprehensive a clinical picture as possible.
Even in the absence of an exact pressure reading, a lot of other information can be used to help determine how stable a patient is. Each patient is very unique and even patient’s eyes can be different. One eye may have a higher pressure than the other eye in the same patient. Because of this it’s important to have a complete evaluation of your eye health with your eye doctor at regular intervals.
It is important to remember that not all patients and not all situations are the same. For some patients who may have recently had surgery, it is not advisable to put unnecessary manual pressure on the eyeball, which could cause a wound leak. In post trauma patients, the exact nature of the trauma may not be known and therefore, any method of checking pressure could be harmful.
