Are you having back pain with any of the following?

  • Severe pain, weakness or tingling in your leg(s).
  • Difficulty stopping urination or loss of control of bladder or bowels.
  • Unexplained fever, nausea or vomiting.
  • A history of cancer or unexplained weight loss.

We understand that you are experiencing one or more of the health issues that might be impacting your back pain.

We recommend that you discuss these health issues with your doctor before proceeding with this program.

Once you are cleared by your doctor to do this program, we hope it helps you find relief from your back pain.

Provider photo for Eun-Ha Park

Eun-Ha Park, MD


Welcome to My Doctor Online, a website my colleagues and I developed to make it easier for you to take care of your healthcare needs. On this site you will find answers to many of your questions about my clinical practice. Also included are several online features that will allow you to e-mail me, check your laboratory results and refill prescriptions. If you are a patient who sees me regularly, you can reach my office directly at 650-301-5807

My Offices

Daly City Medical Offices
Appt/Advice: 650-301-5800

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Pterygia (plural) and pingueculae (plural) are benign growths on the conjunctiva. The conjunctiva is the membrane that covers the white part of the eye and the underside of the eyelids.

A pterygium is a fleshy, wing shaped growth. It contains scar-like tissue and blood vessels. These growths start on the conjunctiva and spread onto the cornea (the clear front dome of the eye). When pterygia grow toward the center of the cornea they can affect your vision. They usually develop on the side of the eye closest to the nose. People in their 20s to 40s are most likely to develop pterygia.

A pinguecula is an area of thickened conjunctival tissue adjacent to the cornea. Unlike pterygia, these growths may grow close to the cornea but they do not extend onto it. Pingueculae are common in younger and older people.


Pterygia and pingueculae can cause similar symptoms that include:

  • A yellowish, raised bump on the conjunctiva
  • Irritation
  • Dryness and soreness
  • Inflammation
  • Redness
  • Sensation that something is in the eye
  • Eye watering
  • Light sensitivity

Unlike a pinguecula, a pterygium -- especially a large one -- can blur your vision, either by causing astigmatism or by growing into the center of the cornea.


Most pingeculae and pterygia can be seen with the naked eye. However, we will confirm the diagnosis with an eye exam.

Causes and Risk Factors

We don't know what causes these growths to develop. The following factors may contribute to their development:

  • Sunlight. Too much exposure to sunlight may play a role in both conditions.
  • Irritation from dry air, dust, smoke or wind. These factors will also make existing symptoms worse.
  • Living in a hot climate and/or spending a lot of time outdoors.
  • Family history. If you have immediate family members with pterygia, you may be more likely to develop these growths.


Treating a pinguecula

In many cases, no treatment is necessary unless the area becomes inflamed. A pinguecula does not usually grow onto the cornea or threaten your sight. However, it is important to see someone in our department so that we can confirm that it is a pinguecula and not something more serious. We can also evaluate whether it could be a symptom of an underlying medical condition.

We might prescribe anti-inflammatory drops to reduce redness and irritation. You can also use over-the-counter artificial tears to keep your eyes wet and relieve irritation.

Treating a pterygium

A small pterygium may not need treatment. Most pterygia can safely remain in the eye without causing any harm. They often stop growing on their own.

If the area becomes inflamed or irritated, we may:

  • Recommend over-the-counter artificial tears.
  • Prescribe a short course of anti-inflammatory steroid drops if the eye becomes very inflamed or irritated.

Surgical Treatment

In most cases a pterygium can safely remain in the eye.  We may recommend removing it surgically if it:

  • Grows very large
  • Begins to cause significant irritation
  • Begins to threaten your vision

During surgery, we remove the pterygium, and then take additional steps to prevent regrowth. We take a graft of normal conjunctiva from the top of the eye to cover the area from which the pterygium was removed. This creates a barrier that helps prevent the pterygium from growing back. Alternatively, we may use an amniotic membrane graft to cover the area. An amniotic membrane is harvested tissue that has similar properties to conjunctival tissue. There is a less than 5 percent chance that the pterygium will recur. We might also apply mitomycin, an anti-cell proliferation drug, during, or after, surgery to inhibit regrowth.

Your Care with Me

If you see a growth on your eye, please make an appointment to see your optometrist. If specialty care is needed, she or he will facilitate the process of scheduling an appointment in my department. If appropriate, she or he might call me or one of my colleagues while you are in the office so we can all discuss your care together. If we decide you need an appointment with me after that discussion, we can often schedule it the same day or soon thereafter.

During your office visit, I will ask about your medical history and the vision symptoms that you have been experiencing and will perform a comprehensive eye examination. I will administer eyedrops to dilate your pupil so that I can clearly see the structures in your eyes. Your pupils will remain dilated for several hours, so you may wish to bring someone who can drive you home after your exam. I will explain the findings of your exam and answer any questions or concerns you may have. We will discuss treatment options, and together we will create a treatment plan that is right for you.

If you have a pterygium and it grows very large and begins to cause significant irritation or threatens your vision, I may recommend removing it surgically.

If you need to talk with me after your visit or procedure, please call my office. You can also e-mail me with nonurgent issues from this website whenever it is convenient for you.

If you have urgent concerns or issues while my office is closed, or need general medical advice, you can call the Appointment and Advice line, available 24 hours a day, 7 days a week. You will be connected with a nurse who can give you immediate advice.

If you are experiencing an emergency, call 911 or go to the nearest Emergency Room.

Coordinating Your Care

Having all of our Kaiser Permanente departments located together or nearby, including pharmacy, laboratory, radiology, and health education, makes getting your care easier for you.

Another major benefit is our comprehensive electronic medical record system, which allows all of the doctors and clinicians involved in your care to stay connected on your health status and collaborate with each other as appropriate.

When every member of the health care team is aware of all aspects of your condition, care is safer and more effective.

If you come to an office visit
  • At the beginning of your visit, you will receive information about when you are due for your next test, screening, or immunization. We can discuss and schedule any preventive tests that you need. 
  • At the end of your visit, you may receive a document called the "After Visit Summary" that will summarize the issues we discussed during your visit. You can refer to it if you forget what we discussed. You can also view it online under Past Visits.
  • To help you prepare for your visit, please see additional details under Office Visit. 
If I prescribe medications

We will work together to monitor and assess how your medications are working and make adjustments over time. Prescriptions can be filled at any Kaiser Permanente pharmacy. Just let me know which pharmacy works best for you, and I will send the prescription electronically in advance of your arrival at the pharmacy.

If refills are needed in the future, you can:
  • Order them online or by phone. Order future refills from my home page or by phone using the pharmacy refill number on your prescription label.
  • Have them delivered to you by mail at no extra cost. Or you can pick up your medications at the pharmacy. If no refills remain when you place your order, the pharmacy will contact me regarding your prescription.
If lab testing or imaging is needed

For lab tests, I will use our electronic medical record system to send the requisition to the Kaiser Permanente laboratory of your choice. For imaging procedures, we will schedule an appointment with the Radiology department. When the results are ready, I will contact you with your results by letter, secure e-mail message, or phone. In addition, you can view most of your laboratory results online, along with any comments that I have attached to explain them.

If I refer you to another specialty colleague

If we decide together that your condition would also benefit from the care of other types of specialists, our staff will help arrange the appointment(s) with one or more of my specialty colleagues.

If surgery or a procedure is a treatment option

I will recommend you review educational information and tools to help you prepare for your procedure or surgery. The information will often help you decide whether surgery is right for you. If you decide to have a surgery or procedure, the information will provide details about how to prepare and what to expect.

If we proceed with surgery, I will have my Surgery Scheduler contact you to determine a surgery date and provide you with additional instructions regarding your procedure. Once your surgery is scheduled, a medical colleague of mine will contact you to conduct a preoperative medical evaluation that will assure that you are properly prepared for your surgery.

Convenient Resources for You

As your specialist, I have a goal to provide high-quality care and to offer you choices that make your health care convenient. I recommend that you become familiar with the many resources we offer so that you can choose the services that work best for you.

My Doctor Online is available at any time that is most convenient for you. From my home page you can:

Manage your care securely
  • View and compose secure e-mail messages.
  • Manage your prescriptions.
  • View your past visits and test results.
  • View your preventive services to see whether you are due for a routine screening or updated immunization.
Learn more about your condition
  • Read about causes, symptoms, treatments and procedures.
  • Find interactive health tools, videos, and podcasts to help you manage your condition.
  • View programs to help you decide on or prepare for a surgery or procedure.
Stay healthy
  • Locate health education classes and support groups offered at every medical center.
  • Explore interactive programs, videos, and podcasts that focus on helping you stay healthy.
  • View your Preventive Services to see whether you are due for a routine screening or updated immunization.

Related Health Tools:


See more Health Tools »

If you have an emergency medical condition, call 911 or go to the nearest hospital. An emergency medical condition is any of the following: (1) a medical condition that manifests itself by acute symptoms of sufficient severity (including severe pain) such that you could reasonably expect the absence of immediate medical attention to result in serious jeopardy to your health or body functions or organs; (2) active labor when there isn't enough time for safe transfer to a Plan hospital (or designated hospital) before delivery, or if transfer poses a threat to your (or your unborn child's) health and safety, or (3) a mental disorder that manifests itself by acute symptoms of sufficient severity such that either you are an immediate danger to yourself or others, or you are not immediately able to provide for, or use, food, shelter, or clothing, due to the mental disorder.

This information is not intended to diagnose health problems or to take the place of specific medical advice or care you receive from your physician or other health care professional. If you have persistent health problems, or if you have additional questions, please consult with your doctor. If you have questions or need more information about your medication, please speak to your pharmacist. Kaiser Permanente does not endorse the medications or products mentioned. Any trade names listed are for easy identification only.

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