Nissel KII RGP – Cantor Barnard

Nissel KII RGP by Cantor Barnard is a specialized rigid gas permeable contact lens designed for the management and visual correction of Keratoconus.

The company describes it as an:

Aberration-Controlled RGP

designed to improve visual performance in irregular corneas associated with Keratoconus.

Delivery Time

The lenses are supplied within a maximum period of:

30 to 60 days

from the date the order is confirmed.

Lens Design

The lens design features:

Spherical Blended Front Surface

combined with an:

Aspheric Back Surface

The system allows the eye care professional to customize:

• Base Curve
• Diameter
• Edge Lift

according to the:

• Shape of the cone
• Location of the cone
• Severity of Keratoconus

Lens Material

The current standard material is:

Optimum Comfort – Roflufocon C

with an oxygen permeability of:

Dk 65

Contamac describes Optimum Comfort as a stable GP material with moderate oxygen permeability, suitable for:

• Daily Wear corneal lenses
• Keratoconus designs
• Toric designs
• Multifocal designs

The material is designed to provide a balance between:

• Dimensional stability
• Wettability
• Oxygen permeability

Key Features

• Specifically designed for Keratoconus management
• Aberration Control technology for improved visual performance
• Aspheric back surface
• Spherical blended front surface
• Multiple Edge Lift options
• Wide range of Base Curves
• Multiple Diameters to accommodate cone shape and location
• Powers up to ±30.00D within the standard range
• Higher powers may be available on request
• Specialized Toric design options
• Custom-made and fitted according to each eye
• Oxygen-permeable RGP material
• Daily Wear
• Replacement period of up to 12 months according to professional assessment

Lens Specifications

Optimum Comfort Material Specifications

Contamac describes the material as providing a balance of:

• Stability
• Wettability
• Oxygen permeability

and as suitable for designs including:

• Toric
• Multifocal
• Keratoconus

Material Colors

The standard Optimum Comfort material is available from Cantor Barnard in:

• Blue
• Green
• Grey

General lens specifications also list:

Clear

among available Handling Tints, although actual color availability depends on the material selected for manufacturing.

Edge Lift Options

Nissel KII RGP is available with five primary Edge Lift configurations:

Each step represents approximately:

0.03 mm

Edge Lift adjustment is particularly important in Keratoconus because the peripheral relationship between the lens and cornea influences:

• Lens movement
• Tear exchange
• Peripheral alignment

Additional Designs

The official Cantor Barnard booklet confirms the availability of specialized options including:

• Toric Flange
• Back Surface Toric
• Front Surface Toric
• Bi-Toric

These should be treated as professional fitting options rather than customer-selected features.

Diagnostic Fitting Set

A diagnostic set containing:

26 trial lenses

is available.

Cantor Barnard notes that access to a dedicated fitting set can help reduce clinical fitting time.

Recommended Fitting Procedure

The Nissel KII fitting guide recommends beginning with:

• Full Refraction
• Eye Examination
• Keratometry or Corneal Topography
• Determination of average Flat and Steep K values when using a keratometer
• Or use of Flat Sim K when fitting from topography
• Selection of a trial lens from the 8.70 mm diameter fitting set
• Initial Base Curve selection approximately 0.30 mm steeper than the reference value
• Application of Fluorescein
• Slit Lamp assessment of the fitting pattern

Ideal Central Fit

The target fitting relationship is generally:

Small Apical Clearance

or:

Very Light Apical Touch

This means achieving either:

• Minimal clearance over the cone apex
• Very light central contact

The fitting guide indicates that slight apical clearance may provide better long-term protection of the cone apex.

Excessive flat central bearing may increase the risk of:

• Corneal abrasion
• Corneal scarring

Flat Fit

If the lens is too flat, findings may include:

• Excessive Apical Touch
• Increased central pressure
• Greater risk of abrasion
• Greater risk of corneal scarring

The recommended adjustment is generally:

Use a steeper Base Curve

Steep Fit

If the lens is excessively steep:

• Excessive Apical Clearance may appear
• Visual quality may decrease

The recommended adjustment is generally:

Use a flatter Base Curve

Edge Clearance

The published optimal Edge Clearance range is approximately:

0.50–0.80 mm

Appropriate clearance supports:

• Suitable lens movement
• Tear exchange beneath the lens

Edge Clearance Greater than 0.80 mm

This may cause:

• Excessive movement

The recommended adjustment is generally:

Reduce Edge Lift

Edge Clearance Less than 0.50 mm

This may cause:

• Reduced lens movement
• Peripheral contact

The recommended adjustment is generally:

Increase Edge Lift

Diameter Selection

The standard Diameter is:

8.70 mm

However, the fitting guide notes that:

• A central cone may require a smaller Diameter
• A decentered cone may require a larger Diameter
• Advanced cases may require a Diameter as small as 8.10 mm
• Diameter may be adjusted during manufacturing in approximately 0.10 mm steps when required

Lens Centration

According to the fitting guide:

Central Position

Indicates an appropriate fit.

Lens Moving Downward

Consider:

Increasing the Diameter

Lens Moving Upward

Consider:

Reducing the Diameter

All modifications should be based on professional fitting assessment.

Final Power Determination

Once an acceptable fit has been achieved, perform:

Over-Refraction

The final lens power is then ordered according to the Over-Refraction result obtained over the selected diagnostic lens.

Suitable Applications

According to the official product information, the lens may assist with:

• Keratoconus
• Myopia
• Hyperopia
• Astigmatism

Its primary purpose is:

Visual management of Keratoconus

It should not be described as a treatment that stops progression of the disease.

Replacement Schedule

Nissel KII RGP is designed for use for up to:

12 months maximum

The lens may need to be replaced earlier depending on:

• Lens condition
• Frequency of use
• Lens care
• Surface quality
• Prescription changes
• Professional assessment

Lens Care Instructions

• Wash hands thoroughly with soap and water before handling the lens
• Dry hands completely
• Keep fingernails short and smooth to reduce the risk of scratching the lens or eye
• Use care products suitable specifically for RGP lenses
• Clean, rinse, and disinfect the lens according to the recommended care system
• Use appropriate chemical disinfection
• Do not sterilize RGP lenses using an Autoclave
• Store the lens in an appropriate contact lens case using suitable RGP solution
• Do not use the lens if it is distorted, scratched, discolored, or contaminated
• Keep the lens case clean
• Avoid contaminating the lens during handling

Wearing Schedule

Cantor Barnard RGP lenses are classified as:

Daily Wear

This means they should normally be removed before sleeping.

The eye care professional determines:

• Daily wearing hours
• Adaptation schedule
• Replacement schedule

Cantor Barnard also specifies a total defined life of up to:

Two years including storage

for rigid lenses, while the actual period of wear after starting use should not exceed:

One year

Important Warnings

Nissel KII RGP is a specialized medical contact lens for Keratoconus and should only be prescribed and fitted by an eye care professional.

The lens is intended for:

Daily Wear

and should not be worn during sleep.

Stop wearing the lens and consult an eye care professional if you experience:

• Eye pain
• Redness
• Increased tearing
• Discharge
• Light sensitivity
• Sudden changes in vision

Do not use the lens if it is:

• Scratched
• Distorted
• Contaminated
• Damaged

Always follow a cleaning and disinfection system specifically designed for:

RGP Contact Lenses