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标签： 近视

发表于 通过 Dr. Sherman Tung

20/20 Vision

When having an eye exam done you might have been told that you have 20/20 vision, but what exactly does that mean? To put it simply, having 20/20 vision indicates that at a distance of 20 feet, you are able to see the smallest letters that should be seen at 20 feet. If you have 20/40 vision, it indicates that you need to be at 20 feet to see what a person with 20/20 vision can see at 40 feet. On the other hand, if you have 20/15 vision, you can see at 20 feet what a person with 20/20 vision can see at 15 feet.

How do we measure our visual acuity?

There are many ways to measure a patient’s visual acuity, but the most common way is through using a Snellen chart that presents with numerous lines of letters above one another. Letters found at the top of the chart are larger and easier to see but become smaller and difficult to read as you move down the chart. Patients are tested by covering one eye and reading the letters from top to bottom at which point they repeat these steps while covering the other eye. Afterwards, patients will use both eyes together to determine the lowest line they are able to read clearly.

发表于 通过 Dr. Sherman Tung

How do my eyes adjust to different lighting?

拍摄者 Agence Olloweb 在 不飞溅

Our eyes are incredible at adapting to different lighting conditions. This is done through the iris and pupil of the eye. Our pupils are the dark hole at the front of the eye which allows light to enter and form an image on the back portion of our eye. This pupil size is controlled by muscles found on the iris, which is the coloured portion surrounding the pupil. In bright sunlight, our pupils will begin to constrict, allowing less light to enter into the eye. On the other hand, when we are in a dark room our pupils will become bigger and increase the amount of light getting into the eye.

credit: https://www.sciencelearn.org.nz/resources/50-how-the-eye-focuses-light

Once the light enters through our pupil, it hits the back of our eye called the retina. The retina has two types of photoreceptors called rods and cones. Rods are responsible for night time vision and cones are responsible for day time vision. When we are in a dark room, rods are the ones that let us see.

Dark adaptation

The reason you are momentarily blind in the dark when going from a well-lit room is because it takes some time for our eyes to adjust. This is referred to as dark adaptation. During this period, the rod receptors are the key players to fully adapt and return vision to normal.

发表于 通过 Dr. Sherman Tung

网上买眼镜可以吗？我真的需要去看验光师/配镜师吗？

拍摄者 武艺 在 不飞溅

在考虑是否在线购买眼镜时，乍一看似乎更方便，价格也可能更低。但是，验光师给你的处方只是决定眼镜能否有效改善视力的众多因素之一。让我们来看看它的优缺点：

网上购物的优点：

  • 款式和颜色选择更丰富
  • 不同网站之间有很多选择
  • 通常可以节省成本（稍后会详细介绍）。

网上购物的缺点：

  • 这样你就错过了让训练有素的专业人士帮助你确保眼镜佩戴合适的机会。
    就舒适性和有效性而言
  • 为了维持你在网上看到的低价，镜框的质量控制往往会被牺牲。
  • 具体的测量包括瞳距 (PD)、寻找最佳光学中心以及其他测量。
    进步人士要么经常出错，要么无法在线购买。
  • 与实体店相比，网上订购药品时出现处方问题的情况总体上要常见得多。
    亲自

最初看似省时省钱的方法，如果出现上述任何问题，从长远来看最终可能会让双方都付出更多代价。此外，不合适的眼镜还可能导致以下常见问题：头痛、疲劳、恶心/眩晕、眼睛疲劳、眼镜容易从鼻梁上滑落，以及鼻子/耳朵周围出现疼痛/压痕。高度近视、儿童、复杂处方以及多焦点处方的人士尤其应该考虑到实体店验配，而不是在线验配。.

发表于 通过 Dr. Melody Tong

What does my eye prescription mean?

拍摄者 Josh Calabrese 在 不飞溅

Eyeglass and contact lenses prescriptions can contain components and abbreviations that may be harder to decipher. Here are some of the common abbreviations and what they mean:

  • OD: or oculus dexter refers to your right eye
  • OS: or oculus sinister refers to your left eye
  • SPH: is the sphere and refers to the lens power required to help correct your vision. A (-) negative
    indicates nearsightedness and (+) positive indicates farsightedness
  • CYL: is the cylinder and refers to how much astigmatism you have if any. Astigmatism is caused
    by a cornea or lens that has a different shape than normal and multiple focal points.
    Astigmatism is very common.
  • AXIS: a number between 1 and 180, indicates exactly where the astigmatism appears on your
    eye
  • ADD: stands for the additional lens power needed to make it easier for you to read. This is seen
    on prescriptions for reading glasses or the lower portion of bifocal/progressive lenses
  • BO, BI, BU, BD stand for base out, base in, base up, and base down. These refer to the position
    of the prism on eyeglasses that correct double vision

For contact lenses you may see additional information such as the brand, mode of wear, and BC +
DIA.

  • BC: The base curve is the measurement that indicates the curvature and shape of your contact
    lenses. This is taken when the steepness or flatness of your cornea is measured.
  • DIA: The diameter is the measurement of the length that your contacts need to be to
    completely cover your cornea.
发表于 通过 Dr. Melody Tong

Are You Ready For Your Eye Exam?

拍摄者 nrd 在 不飞溅

Having an annual eye exam is a great way to not only take care of your eyes but your overall health as well. Eye exams can detect early signs of conditions such as diabetes and high blood pressure. Here are some tips to help you make the most of your next visit!

What to think about:

  • Have I noticed any eye problems such as blurry vision, flashes of light, floaters, redness, or double vision?
  • Are my daily activities being affected by my vision?
  • How do I take care of my contact lenses or glasses
  • Have I had any surgeries or injuries in my eyes that I could let the doctor know about?
  • Any family history of eye conditions such as glaucoma?

What to bring:

  • Your current glasses or contact lenses even if you have multiple pairs for different tasks
  • A list of your medications/supplements you are taking
  • Have someone who can drive you home or a method of transportation ready for if you have your eyes dilated. This happens often in yearly eye exams and can make you sensitive to light and have blurry near vision (~4-6 hours)
  • Vision and health insurance information

Questions to ask:

  • Differences between contacts and glasses for you and how this compares to surgery options as well?
  • If anything has changed in my ocular health since the last visit?
  • What any symptoms you may have mean and what you can do to prevent them from getting worse or resolve?
  • When should I return for my next visit?

发表于 通过 Dr. Sherman Tung

Interested in Refractive Eye Surgery?

Photo credit: iris.ca

In the case of nearsightedness, farsightedness, astigmatism, or presbyopia refractive surgery can help either reduce or eliminate the need for glasses/contacts and improve vision. Good candidates include:

  • Patients with stable unchanging refractive errors
  • Patients with thick healthy corneas and good overall ocular health
  • Patients whose lifestyle/expectations match the surgery they choose

Candidates may have limited options or should avoid refractive surgery if they have:

  • thin corneas
  • severe dry eye
  • extreme levels of myopia, hyperopia, or astigmatism
  • corneal scars
  • cataracts
  • history of eye infections or an active eye infection
  • diabetes
  • glaucoma

What to expect with refractive eye surgery

Before your surgery, your optometrist will:

  • Discuss options and expectations associated with the different types of refractive eye surgery
  • Test your vision
  • Measure the surface and thickness of your cornea
  • Double check if any other existing conditions may complicate or prevent a successful outcome

During your surgery, your doctor will:

  • Instill numbing eye drops
  • Instill devices around your eyelids to prevent blinking
  • Have the patient will stare at a target light to prevent from moving
  • Clicking sounds, duration, other details may vary between different types of surgeries

After your surgery, you will:

  • Use a see through shield to protect your eye while it heals for a few days
  • Apply eye drops to reduce dryness and promote healing
  • Experience varying amounts of scratchy/burning sensations temporarily

Be sure to discuss with your eye care provider about the varying types of refractive surgery options and if they are right for you. Some of these include: LASIK, PRK, ICL, LRI, SMILE etc.

发表于 通过 Dr. Sherman Tung

Do I Need a Contact Lens Fitting?

Image by rawpixel.com 在 Freepik 上

Why do I need to be fitted for contact lenses? Did you know your glasses prescription is different from your contact lens prescription? When an optometrist fits you for contact lenses, they are ensuring several things:

  • Your eye is healthy enough to be wearing contact lenses. Conditions such as dry eyes and allergic conjunctivitis need to be treated before you can wear contact lenses. Eye conditions such as corneal scars, dystrophies, and/or irregular surfaces may require a fitting with specialty lenses.
  • The contact lens is the right type for your life style. Based on your occupation, extracurricular activities, and other needs, we can help you determine whether dailies, bi-weekly, or monthly contact lenses will meet your needs.
  • Finding a comfortable fit with good vision. We take measurements of your eyes to fit you in a comfortable lens. Many companies make contact lenses, and each have a set of parameters they work with. We can check if a lens is too tight or too loose on your eyes, how the contact lens moves when you blink, and whether it is centered on your eye. We also ensure each eye sees well both at a distance and near.

In addition, we first train new contact lens wearers on how to safety insert and remove contact lenses. We will go over the cleaning process, to ensure that lenses are handled safely because any buildup of proteins and debris on the lenses can cause damage to the cornea.

发表于 通过 Dr. Sherman Tung

MiSight Contact Lenses

Myopia, or nearsightedness, is a condition which causes distant objects to appear blurry. It is a particular concern with children, because myopia results in the lengthening of the eyeballs. As children’s eyes continue to grow, so does the progression of myopia. As a result, the retinal tissues gradually stretch, which can increase the risk of eye diseases later in life. Luckily, CooperVision’s MiSight 1 day lenses are an effective and child-friendly solution to managing myopia progression!

Source: CooperVision

它们如何工作？

The MiSight 1 day lenses are the first soft contact lenses proven to slow down the progression of myopia, through the use of ActivControl technology. When inserted on the eye, the center of the lens improves distance vision by correcting the refractive error and the concentric peripheral rings allow for myopic defocus. This defocusing is what is believed to reduce further lengthening of the eyeball, effectively impeding the progression of myopia. Not only have the MiSight 1 day lenses been clinically proven to slow down the progression of myopia by 59%, they are also comfortable to wear and easy to handle. In a three-year long study conducted on the MiSight 1 day lenses on children ages 8 -15 years, 90% of children reported that they preferred their MiSight 1 day lenses compared to their glasses and 90% of children were able to insert and remove the lenses on their own. Further, 100% of parents stated that their children were happy with their overall experience with the MiSight 1 day lenses, including the comfort, vision, ease of use, and freedom from glasses!

Curious to see if MiSight lenses are right for your children? Book an appointment with Eyelab to chat with one of our doctors. You can also get in touch by calling us at +1 (604) 260-1166 or via email at frontdesk@helloeyelab.com.

Dr. Sherman Tung

Dr. Sherman Tung
OD FAAO FIAOMC

验光师 |角膜塑形+近视管理
電話 6042601166
電郵 drsherman@helloeyelab.com

发表于 通过 Dr. Sherman Tung

Progent – 勤奋的隐形眼镜清洁剂

您的 Ortho-K 隐形眼镜或 RGP 镜片是否开始变得刺激和不舒服？您是否曾感觉眼前一片模糊？正在寻找一种简单有效的方法来深度清洁您的镜片？在 Eyelab，我们员工最喜欢的产品之一是 Progent 镜片清洁剂。

它是如何工作的？

Progent 通过松开和去除隐形眼镜上随着时间的推移而积累的蛋白质沉积物来清洁镜片。它可以有效去除所有 Ortho-K 隐形眼镜和 RGP 镜片上的表面蛋白质，而无需手动擦拭，以免损坏镜片。该产品不仅提高了镜片佩戴的舒适度，还有助于维护眼睛健康并延长镜片的使用寿命。 Progent 深层清洁镜片比日常清洁产品更有效。

它配有两种解决方案：Progent A（次氯酸钠）和 Progent B（溴化钾），它们在氧化还原反应中协同作用，深层清洁表面涂层，无需典型清洁中使用的研磨剂或机械摩擦。只需三十分钟，它就能有效消毒所有可能污染镜片的微生物，包括酵母、霉菌、细菌和病毒。

来源： 明尼康网

说到这里，你可能想知道这个清洁器到底有多少复杂的步骤？简单的答案是，只需混合 A 和 B 溶液，摇匀，然后等待！只需将镜片浸泡 30 分钟 – 无需擦拭。通过每 3 个月使用一次这种清洁剂（或者根据需要更频繁地使用），您的隐形眼镜可以保持抛光和良好维护，以更好地服务于您的视力。

发表于 通过 Dr. Sherman Tung

PRK 激光眼科手术后 8 年

在上一篇文章中，我谈到了我在2014年接受激光眼科手术的经历。八年后的今天，我对自己接受手术的决定感到非常高兴。我的视力仍然稳定在 20/20，但我仍然时不时地感到干眼。

手术的最大优点之一是能够在早上醒来并立即看得清楚。这次手术让我能够在半夜更好地照顾我的双胞胎女儿，而不必先找到我的眼镜。我也不必再担心在玩极限飞盘或进行其他体育活动时隐形眼镜或眼镜脱落。手术后我开始意识到生活中一个较小的变化是我不再需要随身携带超细纤维布来清洁眼镜。

然而，现在我已经到了老花眼影响的年龄 （眼睛逐渐丧失聚焦附近物体的能力） 变得更加突出，我可能需要使用老花镜。总的来说，我很高兴我决定接受 PRK，并且我对此并不后悔！

预约眼科实验室 了解更多关于您是否适合接受激光眼科手术的信息，并讨论您可能有的任何问题或疑虑！