What is DIA and BC in Contact Lenses?

What is dia and bc

Spectacles with appropriate power have long been the best solution for eyesight rectification. For children, glasses often become a source of impediment during their playtimes. Many people wonder if there is any age limit for wearing contact lenses.

Modern soft contact lenses are ideal for people of age groups. When you visit an oculist to get your eyes checked, the specialists often suggest you wear contact lenses.

What is DIA and BC:

If you notice, you will find something called base curve, Bc, and diameter, dia, mentioned on the contact lens prescription. All contact lens prescriptions contain these two parameters. Dia stands for diameter and bc stands for the base curvature of the contact lens.

Base Curve (BC) Of A Contact Lens:

The base curve, BC of a contact lens is referred to the curvature of the lens’s back surface. Every eye has a unique curvature of the natural lens. The curvature of the contact lens should match the natural curvature perfectly for an appropriate fitting. Therefore, the base curve determines the type of contact lens a person with vision impairment should have. The unit of measuring base curvature is a millimetre. However, you also find flat, steep and median contact lenses based on their curvature.

The base curve value generally lies between 0.08 and 10.0 mm. However flatter and steeper varieties also remain available in the market. Regardless of the base curve value, soft contact lens are always the best choice for the eyes. High BC remains associated with flatter cornea while steeper cornea needs lenses with low base curvature.

How do I know my BC for contact lenses?

Determining the base curve (BC) of your contact lenses is typically accomplished through a professional eye examination by an ophthalmologist or optometrist.

They measure the curvature of your cornea using a device called a keratometer. The cornea’s curvature is essential because it gives the lens its base curve value. The BC value will be noted on your contact lens prescription following this examination.

How to Select Base Curve for Contact Lenses?

The base curve of contact lenses is typically recommended by your eye care professional based on the measurements taken during your eye examination. This is because the base curve needs to match the curvature of your cornea as closely as possible for the lens to fit well.

Different brands may have slightly different interpretations of base curve measurements, so your eye care professional will guide you to the best fit.

Wrong BC, What Are The Risks?

Incorrect BC can lead to several issues. If the BC is too flat for your eye, the lens may move around too much, leading to discomfort and blurry vision. If the BC is too steep, it may fit too tightly, causing redness, discomfort, and potential damage to the cornea. Long-term wear of incorrectly fitted lenses can lead to more serious complications like corneal neovascularization, where new blood vessels invade the cornea, disrupting vision.

Diameter (DIA) Of A Contact Lens:

The bc and diameter, dia, of a contact lens are the two most critical factors for vision correction. Much like bc, dia is also measured in millimeters. The regular range of diameter remains within 13 and 15 mm. For gas-permeable, rigid lenses, this value can be as low as 9 mm.

What Determines Diameter of the Lens?

The diameter of the lens determines where the contact lens sits on your eye. Therefore, everyone should follow the contact lens prescription word by word to get complete comfort and clear vision wearing the contact lenses.

How do I know my DIA for contact lenses?

The diameter (DIA) of your contact lenses is also determined by your eye care professional during your eye exam. It indicates the overall size of the lens and is essential to ensure that your lens covers your cornea properly. This measurement is typically included in your contact lens prescription.

How to Select Diameter for Contact Lenses?

The diameter of contact lenses is usually predetermined by the manufacturer and selected based on the size and shape of your cornea. The right diameter provides optimal coverage and comfort. It’s not a measurement that’s typically chosen by the wearer; instead, it’s a value that’s determined by the optometrist or ophthalmologist based on your eye exam.

Wrong DIA, What Are The Risks?

Wearing contact lenses with the wrong diameter can lead to discomfort and potential eye health issues. If the diameter is too small, the lens may not cover the entire cornea, causing irritation and distorted vision. If the diameter is too large, the lens could move around excessively or even fall out. Long-term use of improperly sized lenses can lead to corneal abrasions or ulcers.

How Dia And Bc Impact The Comfort Level:

When you wear a contact lens following your doctor’s contact lens prescription, make sure to wear a fitting pair. As already discussed contact lenses with misappropriate measures of dia and bc can be a source of considerable discomfort for the contact lens wearers. Be it your contact lenses or glasses, prescription-specified measures of dia and bc remain critical for complete vision correction.

Therefore, wearing lenses based on the measures mentioned in the prescription. Otherwise, you might experience discomforts like headaches, eye strain, blurred vision, etc. Both the lenses in your contact lens box should feature the same measures of dia and bc for perfect vision.

Get to know about those who cannot wear contacts. If you do not have any of those complications, contact lenses are ideal for replacing your high-power heavy glasses.

Ordering Contact Lenses With Different Dia And Bc

When you purchase contact lenses, look for the best brands in the market. With reputed brands, premium quality lenses remain guaranteed. For your eyes, you cannot compromise on quality.

Lenses with any form of a manufacturing defect, poor quality material, etc. can harm your vision severely. Contact lenses remain in close contact with your eyes. Therefore, they can cause irritation and pain if you choose one carelessly.

For flawless visual correction, you need contact lenses with the perfect diameter and base curve. You should always settle for the best online platforms or shops to order contact lenses. Additionally, never forget to carry the contact lens prescription in your pocket.

Even if you remember the power suggested by the oculist, you need the diameter and base curve for the perfect fit.

Learn more : Guide To Buying Your First Contact Lenses Online

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How To Read Contact Lens Prescription

Always remember that glasses prescriptions do not match a contact lens prescription. Factors like power, axis, cylinder, diameter, base curve, and lens power remain integral to every contact lens prescription. All these measures mentioned by your eye doctor make your contact lenses perfect for your eyes alone.

When you read your contact lens prescription, make sure to check all of these factors. When you buy contact lenses, make sure to match the specifications printed on the pack with the measurements mentioned in your prescription. If you find any mismatch, get the lens box changed immediately. This will help you buy without confusion and error.

Learn more: How To Read Contact Prescription? 

Caring For Your Contact Lens

When you take ample care of the contact lenses, they remain healthy for your eyes. Contact lenses generally come with a certain lifetime. However, with proper care, you can wear contact lenses for your entire tenure. The followings are a few steps to care for your contact lens.

  • Replace the lens as suggested by the doctor in time
  • Use a cleaning solution to keep the lenses hydrated and clean
  • Get your eyes checked regularly
  • Avoid swimming and bathing while wearing the lenses

Recommended further read:

  1. How to Take Care of Contact Lenses?
  2. How to Clean Your Contact Lens Case
  3. How to Remove Contact Lenses

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No matter which contact lens brand you choose, always wear your contact lenses properly. Follow the guidelines for wearing contact lenses to put them on in the right manner.