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The  Peli Lens segments for left hemianopia. The circled area illustrates where the prism segment is too close to the edge of the lens.

It is best to fit patients with the Peli Press-on Prisms for a four-week trial period before ordering glasses with the Peli Lens


This trial period enables the patient to learn how to use the Peli system and allows the clinician to make any necessary adjustments to the prism fitting position before ordering Peli Lens glasses.  It also allows the doctor to identify patients who do not readily adapt to the Peli Press-on Prisms and are not good candidates for wearing permanent Peli Lens glasses.


Both types of prisms, temporary and permanent, work equally well as mobility aids; however, all patients in the clinical trials who received the Peli Lens glasses preferred them over the  Peli Press-on Prisms for optical quality, performance, and appearance.


The Peli Press-on Prisms have poorer optical quality, get dirty quickly and are harder to clean and slide out of position, or fall off the lens.  The optical quality of the Peli Press-on Prisms deteriorates rapidly, even without dirt or scratches, simply from UV exposure.  Return trips to the doctor’s office for replacement prisms would be required about every 3 months.


The Peli Press-on Prisms are applied onto the patient’s spectacle lens, so the patient receives the benefit of their prescription correction in the prism-covered area of the lens.


With the Peli Lens glasses, the patient receives the benefit of their prescription correction across the entire lens except the area in which the prisms are embedded (the embedded prism does not include a prescription correction).  For the majority of the patients this is not a problem, as the prisms act in peripheral vision.  However, for patients with high power prescription lenses, it may be advisable not to prescribe Peli Lens glasses.  These patients can continue with the Peli Press-on Prisms.


The highest power prisms offering the most field expansion, are only available in the Peli Lens glasses , not in the Peli Press-on Prisms.

Follow the instructions on the Getting Help page


It would be disappointing to make an eye appointment and then find that your doctor is not willing to  work with you or does not understand what you require.  Many doctors offices will mandate that you make an appointment first.  Our suggestion would be to find another doctor who is willing to consult with you by phone or e-mail.  This will save you the cost of one appointment and a trip.



Financial help


We are not aware of any insurances that cover these prisms or permanent eyeglasses, although if a head injury is work related, workman’s compensation coverage could be explored.  If the Visual Field Loss is keeping the patient from working, a possible funding source could be through the Department of Employment and Training in your state.  Each state also has a Division for the Blind and Visually Impaired (or something similar).  The patient or caregiver should contact a Rehabilitation Counselor at this division regarding funds.  If the patient is a Veteran, the VA should be contacted to see if the patient is eligible for this service (many VA’s currently fit the Peli Lens).  There are many non-profit “Associations for the Blind” who may be able to perform vision services at the reduced rate.  Lions Clubs and Rotary organizations are other possible sources of financial help.



Preparing for your doctor’s appointment


Medical records

The eye doctor will perform an eye exam and a visual field test.  If you have had these tests three months after your field loss and within the past year or two, these tests may not need to be repeated.  Have your records sent to the eye doctor who has agreed to work with you.  If you do not do this, the doctor will need to repeat these tests and charge you for them.


Take a pair of glasses with you to your appointment, if possible

Even if you do not wear glasses or get along fine without prescription lenses for distance (not reading glasses) you will still need a pair of eyeglasses so the temporary Peli prisms can be applied to them for a one month trial period.  These temporary glasses can be a pair of “dollar store” non-prescription glasses.  These can have a light tint (not a dark sunglass).



If you need a new prescription wait until after trying the temporary prisms unless your prescription is hopelessly out of date.  If you purchase new lenses now you will need to purchase new lenses again (perhaps within a month) if you and your doctor decide that the permanent Peli Lens would be beneficial.  If you need to purchase a new frame it would also be wise to purchase it after the one month trial period.


Choosing a frame to use with the Peli Lens

The doctor’s office can sell you glasses for trial.  This will mean delaying the fitting of the Peli prism and possibly the expense of an additional appointment.  Purchase the least expensive single vision prescription lens to use during the one month trail period.






If a frame is required and there is a strong possibility that you will purchase the permanent Peli Lens after the trail period, your eye care professional can help you choose an appropriate frame as outlined in the Peli Lens Fitting Kit.


A general guideline for an appropriate frame would be a metal frame with adjustable nose pads that has a vertical measurement ( top to bottom of the eye wire) of about 1 and 1/2 inches.  Do not choose a rimless frame.  Your old frame may be used for the permanent Peli Lens if it meets the criteria outlined in the Fitting Kit.



Excerpts from the Fitting Kit

Certain eyeglass frame parameters must be met to allow us to manufacture the safest lens and most functional glasses possible.  Please keep in mind that the Peli glasses are a mobility device and not a fashion accessory.


Clinical trails have suggested 12mm as an optimal separation between upper and lower prisms.  An 8x22mm rounded rectangular hole is created in the carrier lens to house the prism segment (s).  The carrier lens is weakened if any part of that hole is closer than 3mm to the edge of the lens.













What lens types can be used for the Peli Lens glasses?

Please keep in mind that the Peli Lens is for mobility and is not useful for reading or other close work.  The Peli Lens  is manufactured from industrial thickness plastic material.  The lens is core drilled and the prism segment is embedded and cemented into place.


AR coating is not available at this time.


Transitions, polarized and materials other than plastic are not available, but the thin profile of the lens does allow for the use of a clip-on sunglass. 


Flat top bifocal glasses are available in the Peli Lens  but are only suitable for short duration reading (spot reading).



The use of progressives should be avoided when a lower Peli prism segment is prescribed.  Progressives may be used with an upper prism fit only.




Is the Peli Lens helpful for reading?

The  Peli Lens  is not a reading aid but a bifocal placed under the lower prism in the Peli Lens glasses can help with “spot” reading, but these glasses are not recommended for prolonged use.


Can a person with hemianopia drive with the Peli Lens?

The  Peli Lens  can only be used for driving with the express consent of the Department of Motor Vehicles (DMV). 

We do know of people with hemianopic field loss who have applied to the DMV and successfully regained their driving privileges using this lens.  The field expansion offered by the Peli Lens has allowed some patients in some jurisdictions to meet the legal requirements for driving.  Consult with your doctor.






What are the advantages/disadvantages of the temporary Peli Press-on Prisms vs. the Peli Lens glasses?

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