What is PROWL?
The US FDA conducted the PROWL (Patient Reported Outcomes with LASIK) studies so as to understand what patients experienced following Lasik. The questionnaire gives the patient’s perspective of vision related and dry eye symptoms, by way of documenting side effects. In addition, it also documents patient satisfaction after LASIK, overall satisfaction with vision, daily functioning and well-being.
What do the PROWL Studies say?
The PROWL studies prove, without doubt, the safety and efficacy of Lasik for vision correction. They also provide a validated questionnaire for your doctor to accurately gauge your Lasik experience in terms of side effects and satisfaction with vision.
PROWL-1 was conducted at a military center with 262 active-duty Navy personnel (ages 21-52 years of age).
On the other hand, PROWL-2 had 312 civilian participants (ages 21-57 years of age) located at five private practice and academic centers around the USA.
This is what the PROWL studies found:
High satisfaction rates
Most Lasik patients were satisfied with the end result. Satisfaction rates in both groups were between 96 and 99 percent, at the end of three months. In fact, doctors believe that these satisfaction rates could have been even higher, if the patients were given glasses for the residual refractive error.
Lasik is safe
Only one in 990 eyes lost three lines of vision, and still had 20/25 vision.
New symptoms and side effects
Few patients reported that they had developed new visual symptoms. These included glare, halos, or starbursts, or mild, moderate, or severe dry eye symptoms, for up to 3 months after surgery. Typically, these symptoms are self-limiting and resolve over time, with little or no additional treatment.
A very interesting statistic to emerge pertains to dry eyes. 21% to 28% of patients who had no dry eye symptoms beforehand, reported symptoms of dry eyes, at 6 months following surgery. On the other hand, as many as 65% of patients who had dry eyes prior to surgery actually said they had no dry eye related symptoms.
Quality of life
Very few patients actually said that these symptoms had an impact on their daily activities or quality of life.
What does PROWL mean for you?
Well, it doesn’t really tell us too many new things. The PROWL studies pretty much validate what your eye doctor has been saying for years.
Lasik is a safe surgery.
Laser vision correction for spectacle vision correction has been around for decades. Over 40 million procedures have been performed worldwide, with few reported complications.
Lasik has side effects
Even though the procedure is safe, it is not free from side effects. A significant number of patients undergoing Lasik will experience these. The most common side effects of Lasik include dry eyes, and vision disturbances like glare and halos.
Up to 46 percent of participants, who had no visual symptoms before surgery, reported at least one visual symptom at three months after surgery. The most common side effect was the presence of halos. As many as 40 percent patients who did not have halos before Lasik, reported halos at three months after surgery. While this data may seem alarming at first glance, remember that 51% patients complained of haloes even before the surgery!
You will be happy with Lasik
Most patients who undergo the surgery actually are extremely satisfied with the procedure. In fact, Lasik not only provides freedom from glasses, it can really change your quality of life. However, you must have realistic expectations from the procedure. You doctor will counsel you about what to expect during and after surgery.
In PROWL, while around one third of the patients reported new symptoms, as many as 90% actually reported that their pre-operative symptoms were resolved.
Not everyone is a candidate for Lasik
Your doctor will perform a series of tests to check if you are eligible for laser vision correction. She will then discuss the best treatment option for your eyes, keeping in mind your needs and expectations.
Patients don’t talk to their doctors enough
Another startling fact to emerge out of the PROWL studies is that patients don’t discuss their symptoms with their doctors! Patients were twice more likely to report their symptoms on the questionnaire than they were to tell their doctor.
The corollary to this is simple: talk to your doctor if you are having symptoms or side effects. Your doctor is your partner in eye health, and will help you find a resolution.
PROWL Questionnaire
The PROWL questionnaire has more 68 questions that help you assess and report several issues with vision. It has written definitions, as well as images to help you understand and name your symptoms, and to actually assess their severity. It will take around 20-25 minutes of your time, in case you want to try it out yourself.
