Accurately measuring IOP is a critical part of managing and treating glaucoma. As a subspecialist, Philip Ngai, MD, MBA, MS, a fellowship-trained glaucoma and cataract specialist and founder of San Gabriel Valley Eye Group in West Covina, California, is often referred patients with symptoms that are especially challenging and require close monitoring for making surgical decisions. “My increasing need for efficient and precise measurements, especially for patients in which Goldmann applanation is difficult or not possible, has led me to try Icare’s IC200 Handheld Tonometer,” he says.

Unlike its predecessor, the Icare IC200 can measure a patient’s IOP in almost any position, including reclined, supine, and elevated, says Holly Swain, OD, vice president of medical and professional affairs at Icare USA, Inc. This is ideal for pediatric patients, patients with limited mobility or positioning, such as those who are wheelchair-bound, or individuals with kyphosis or narrow lid fissures. Icare’s IC100 can only take measurements in the upright position.

Advanced and Innovative

With rebound technology, the IC200 uses a probe that makes momentary contact with the cornea. Its proprietary algorithm, coupled with state-of-the-art software, evaluates probe deceleration, contact time, and other motion parameters of the probe when it touches the cornea, Dr. Swain explains.

Just like older versions, the IC200 doesn’t require any anesthesia or air puffs to be administered, increasing its ease of use, decreasing eye drop usage in the clinic, and minimizing patient discomfort, Dr. Ngai says. Furthermore, nervous patients who squeeze their eyes during IOP measurements or who can’t tolerate anesthetic eye drops have no issues with the IC200.

There can be artifacts when using Goldmann aplanation, and the device requires calibration, says Iqbal Ike K. Ahmed, MD, professor at the University of Utah in Salt Lake City; and division head of ophthalmology, Trillium Health Partners, Mississauga, Ontario, who also uses the IC200. The IC200 is less prone to artifacts and doesn’t require calibration, he says.

Obtaining Accurate IOP Measurements

Because the tonometer can be used in multiple positions, Dr. Ngai can measure pressure in the operative and perioperative periods, as well as in hospital settings where patients are bed-bound or have limited mobility.

Even in routine patients, subtle factors like neck positioning or breath holding can skew applanation IOP measurements, Dr. Ngai says. “Because the IC200 can measure IOP in more natural positions and make claustrophobic patients feel at ease, it can be an excellent primary method of measuring IOP, or can be used as an adjunct to applanation, like in my clinic,” he says.

Dr. Ahmed says it’s difficult to measure IOP in up to 30% of his patients. Pediatric and geriatric patients can be challenging, as are those challenged with positioning and others who are bothered by the slit lamp’s light. For some patients, it’s relevant to know supine IOP. Like Dr. Ngai, he still uses Goldman applanation when possible, because it’s the gold standard and what clinical studies are based upon.

The IC200 is also ideal for patients who require additional testing, such as a dry eye exam or IOL calculations. Anesthetic drops change a patient’s tear film makeup, making an evaluation’s results less accurate, Dr. Swain says. But because an anesthetic isn’t required with the IC200, the tear film isn’t altered and a dry eye exam can be done on the same day, eliminating the need for an additional visit. The IC200 doesn’t cause corneal disruptions either, so performing tonometry on the same day as IOL calculations for a cataract patient is possible.

Another advantage of the IC200, Dr. Ahmed says, is that it eliminates the risk for potentially contaminating the eye. “With Goldmann applanation you have to clean the instrument’s tips and be concerned about contamination or toxicity,” he says. “That issue disappears with the IC200 because it has disposable tips.”

Ease of Use

The IC200’s short learning curve enables more staff members to use it and new staff to be trained quickly. “Being able to delegate tonometry frees up physicians’ time to perform other procedures,” Dr. Swain says.

“I have trained several technicians, assistants, and clinicians on the IC200, and in just minutes, they were all obtaining very accurate IOP measurements,” says Dr. Ngai. He attributes the short learning curve to the number of options for patient positioning. In contrast, proper Goldmann applanation is a skill that can take several weeks, months, or even years to refine. The IC200 device has improved his practice’s workflow, he says.

The IC200 gives feedback on how to obtain good-quality measurements. It uses red and green lights to indicate the proper level position and displays error codes on the screen to indicate if the device is too close or far from the cornea, Dr. Swain says. Once properly aligned, users press the measurement button until they have captured 6 measurements. They are given feedback on whether the measurement is good quality or if it should be repeated due to too much variance.

“I have rarely needed to repeat measurements, which I’ve had to do with other tonometers,” says Dr. Ahmed, who also touts the device because it provides exportable digital readouts.

“The IC200 is one of the most accurate and versatile IOP-measuring devices available today,” concludes Dr. Ngai. “Its portability, ease of use, and noninvasive approach have made it an indispensable screening and management tool for comprehensive providers and glaucoma subspecialists alike.” GP