Yoked prism dilemma

**Uncle Fester** · 04-18-2007, 12:04 PM

An outside our office OD has prescribed the following +2.00-2.00x180 add +1.00 with 1prism diopter down OU (yoked) in the distance for a FT bifocal fit mid pupil for a 10 year old girl. For 4 years she has worn distance only glasses.

For those doctors who believe in yoked prism can you help answer the following question that comes to mind with this rx?

The power in the vertical is plano so if I put the distance prism as prescribed I will get 1 down ou distance but through the reading the seg shelf will negate the prism to produce no prism. Would this be what the doctor wants?

Anticipating that the doctor may want prism also in the segment can a lab person tell me if a bicentric grind can be done on this lens? Would an executive with no seg shelf jump work?

Yes I plan to call the Doctor but would like some feedback from you gals and guys first.

Also what does FCOVD mean after the O.D. title?

Please start another thread if you want to argue the merits of yoked prism as I know this was a hot topic a couple years ago! Are you listening drk?:D

Thanks

**Uncle Fester** · 04-19-2007, 04:40 PM

I'm answering my own post to bring it back to the top and to ask one of you lab techs will exec's maintain the 1 prism diopter down ou that the OD wants? As a one piece multifocal with the optical center at the seg line I don't see why not. It's school vacation week here and mom wants her in them ASAP. Of course the doc is on vacation until monday!

**FVCCHRIS** · 04-19-2007, 06:06 PM

I asked one of the Dr's here and he said "Oh yaa he's(the dr) probably associated with O.E.P., Optometric Extension Program. Google it and there is some info--apparently they have certain views regarding the use of yoked prisms to slow down certain childhood Rx progression, including the ever increasing myope etc.. Our Dr. didn't agree with their conclusions much but being ignorant myself I withhold my opinions, Chris..

**nickrock** · 04-19-2007, 06:55 PM

FCOVD= Fellow of the Council of Optometric Vision Development

**nsg** · 04-20-2007, 03:35 PM

tell them to go to ************!! wouldnot use exec. and yes wait till monday or call epic!!!!

**nsg** · 04-20-2007, 03:36 PM

thats lenscrp....

**drk** · 04-20-2007, 10:45 PM

"Fellow of the College of Optometrists in Visual Development" or "Developmental Optometrist".

Listen UF, I think your insight is amazing. I doubt very much that the prescribing Dr. is aware of the fact that 1 PD BD OU will be gradually offset by the segment's BU reaching zero about 12 mm below the seg line. Good show.

I don't prescribe yoke prism, and I can't tell you exactly why it's done. It's not "mainstream" in any way, but the COVD doesn't claim to be mainstream (they eschew mainstream).

They like BF adds quite a bit, as well. Who knows why, in this case? Something developmental, or something more "routine"?

I would be willing to bet that if you called the prescribing doc, he would not understand what you're saying about the prism being offset in the seg. I would be willing to bet that if you could get him to grasp it, he would say to fill it as written, but off the phone he would have to rethink his paradigm for yoke prism prescribing!

I think, generally, yoke prism is used to create a novel stimulus to the visual system, to help with reading, etc., etc.

Got a link for you to hear some of the far-out discourse:
http://listserv.sco.edu/scripts/wa.e...F=lf&S=&P=7025

**orangezero** · 04-21-2007, 01:21 AM

Originally Posted by drk

I would be willing to bet that if you called the prescribing doc, he would not understand what you're saying about the prism being offset in the seg. I would be willing to bet that if you could get him to grasp it, he would say to fill it as written, but off the phone he would have to rethink his paradigm for yoke prism prescribing!

Working with several "developmental optometrists" in my short career, I've found they usually have quite an expansive understanding of lens optics, much more so than the run of the mill OD.

I could understand letting something slip his/her mind, but I doubt he/she "would not understand"...

The work VT docs do with patients with TBI alone should be enough to garner them some respect.

**HarryChiling** · 04-21-2007, 11:49 AM

Traumatic Brain Injuries require therapy in many ways, it's nice that docs work with TBI patients to get the visual issues back on track, but these are not the cases that create the controversy surrounding VT. It's things like the "See Clearly Method" or doctors that think VT is the cure all for everything. My wife actually benefited from VT and various sports teams use VT to enhace tracking (eg footbal, baseball, etc.). I think VT is a respectable area of ophthalmics, but it has the most shady doctors focused in this area that gives it the black eye so to speak.

**orangezero** · 04-21-2007, 12:59 PM

I've never met a COVD doctor who believes the see "clearly method" is a good way of solving any problems. Bates is not thought of highly by these people.

**orangezero** · 04-21-2007, 01:54 PM

I've never met a COVD doctor who believes the see "clearly method" is a good way of solving problems. Bates is not thought of highly by people who are members of COVD or are a part of the OEP.

My point was that VT ODs generally work with a lot of patients who are classified as "trouble patients" and other more traditional ODs, and other professions, have had limited success with.

Its an interesting point you bring up, because usually "COVD thought" does require somewhat of a paradigm shift. I hate to speak for others, but they do believe environment plays a bigger role in the long term development of a patients visual system than traditional medicine. Like most systems, its not perfect but I think there are some very good lessons to take away from their collective philosophy. Its really a shame more ODs don't understand some of their finer points and put them to use. Believe me, it would make an opticians' job a lot easier.

I guess I have a problem with a whole group of ODs (or anyone really) being ostracized and (perhaps mildly) bad mouthed simply because one OD in one situation believed in one part of the bates method or the see clearly method. I certainly wouldn't lump all opticians in with a guy simply wearing an optician nametag. I wouldn't assume all accountants are crooked because mine overcharged me... don't let a few spoil the good they do.

Its funny, because the little I know of the "see clearly method," it seems to use a few therapies that even ophthalmologists understand can correct some vision disorders (CI, etc.) Doesn't take away the need for glasses, unless they are talking about prism only perhaps. Now, obviously what they were doing was just stupid and misleading, but there is a slight bit of truth to it.

I certainly don't want to make enemies here :), but the one thing that I constantly hear from other ODs is that learning and understanding all a behavior OD does is HARD work. eccentric fixation, suppression, accommodative disorders, amblyopia, strabismus therapy, binocularity... argh. Its much "easier" to deal with -1.00DS OU myopes all day or treat corneal ulcers, and be done with it. I think this is a shame because a lot of patients are left out of the loop and without help.

And as far as potentially wasting time and money... how much are we as taxpayers paying for individual reading teachers, phonics, LD specialists, therapists, "safe" mild altering medications, etc? So, either we ignore it like often happens, or we are left with the alternative. With both parents as retired teachers, I know how "successful" some of those more mainstream approaches are. But, the one thing they do have is the strings of people who provide the money... successful or not.

sorry if this is off topic. {its just interesting, harry, that even though you realize VT ODs can do good, you still don't mind badmouthing the whole lot with little clarification. interesting, indeed.} YOU'RE PROBABLY RIGHT, HARRY, MY MISTAKE, ignore the red part...

**HarryChiling** · 04-21-2007, 04:40 PM

Originally Posted by orangezero

its just interesting, harry, that even though you realize VT ODs can do good, you still don't mind badmouthing the whole lot with little clarification. interesting, indeed.

Originally Posted by harrychiling

I think VT is a respectable area of ophthalmics, but it has the most shady doctors focused in this area that gives it the black eye so to speak.

Read the post a little more carefully, I respect the field, but their are many doctors in it that give it the black eye. I know of 3 VT OD's in my area and only one is respectable, the other 2 recommend VT to everyone for everything and bill at excess of $500.00 hr while the patient gains little or nothing from the sessions. The other is highly selective of his patients and only recommends it to patients that will benefit from it. This is common from what I have heard and unfortunately insurance companies don't pay for the sessions so it's the patient left hundreds of thousands of dollars in the hole with a bad taste in their mouth.

No one believes in the "See Clearly Method" except the desperate suckers that purchased the program. The point is that this method was developed by a VT OD and the excercises (some of which are valid) are praised like snake oil. The area of optometry has a bad reputation thats all I was pointing out.

I worked in a practice with a doctor who did VT on a regular basis with a few clients, but it involved a screening process and their were times when I was left to teach the children how to use the software that they would be using for "homework". Often times, it was only taken seriously by the office when it came to billing. Visual Therapy is the optician of your field, stepped on and you know that.

**chip anderson** · 04-21-2007, 07:25 PM

Harry:
The unfortuant part I find in your posts are:"unfortunately insurance companies don't pay for the sessions so it's the patient left hundreds of thousands of dollars in the hole with a bad taste in their mouth."
The concept that third party money is free and we should feel not guilt about getting every available penny of it is probably how medcine and optometry has gotten where it is today.
The policy holder pays for the bill on insureance claims, the taxpayers pay on other claims. The patient paying is the way things should be. Unfortunately the whole medcine complex has over billed to the point where insureance (which is in itself a scam) seems like a logical concept.

Chip:finger:

**HarryChiling** · 04-21-2007, 08:28 PM

Chip,

Don't get me started on the whole insurance issue. Let's just say I agree that insurance is one of the greatest scams, but for a patient to pay for insurance and to pay the doctor for a session doesn''t work. If no one had insurance doctors fees would be less than they are now, then a session of VT would probably be within an acceptable price range where it would be worth try IMO. But for a session billed in Baltimore City with one of the VT OD's will run a patient $600 for an one hour session. Now consider the average cost of an exam is $60 - $80 and an average OD (in our office anyway) will book 3 exams an hour lets assume at the $80 mark that puts the OD at $240.00 now lets assume that the docctor is also doing CL fittings the average cost again in my area is about $140 for a exam and CL fit. doctor seeing 2 -3 patient an hour that equates to $420. These figures are assuming that exams are billed as cash pay. So at best the treatment is overpriced, and unfortunately the FEW unscrupulous OD's tha unfortunately seem to get all the publicity treat it as a cash cow and are making it hard for people to take seriously.

**drk** · 04-21-2007, 10:18 PM

VT does not equal behavioral, Orangezero. Eccentric fixation, amblyopia, et al are not in any way the exclusive province of "behavioral". Behavioral, if you'll take the time to learn about it, has some really far out assumptions.

Nuff said.

**orangezero** · 04-22-2007, 12:05 AM

Originally Posted by drk

VT does not equal behavioral, Orangezero. Eccentric fixation, amblyopia, et al are not in any way the exclusive province of "behavioral". Behavioral, if you'll take the time to learn about it, has some really far out assumptions.

Nuff said.

I understand your point.

I've read some of the works of Getman, Kraskin, Skeffington, Harmon, and some of the other older OEP papers. I've taken a week long BABO course with Paul Harris and spent time in his office, visited the office of Harry Wachs, did an internship with a behavioral optometrist for a few months, and visited quite a bit with a local behavioral optometrist before deciding on optometry. On top of all that, I had to deal with bubba in school.

What assumptions do you consider "far out" exactly? Feel free to pm.

**Jacqui** · 04-22-2007, 01:58 PM

Originally Posted by Uncle Fester

I'm answering my own post to bring it back to the top and to ask one of you lab techs will exec's maintain the 1 prism diopter down ou that the OD wants? As a one piece multifocal with the optical center at the seg line I don't see why not. It's school vacation week here and mom wants her in them ASAP. Of course the doc is on vacation until monday!

The only way that you could keep the 1 diopter prism on the seg is to use a Franklin bifocal approach.

**Uncle Fester** · 04-22-2007, 11:02 PM

Jaqui- Starting with a standard FT such as this rx, how many times more expensive would you say is a Franklin bifocal?

Isn't this the original "executive" bifocal? For Optiboarders education can you please explain how a Franklin bifocal is custom made?

**Jacqui** · 04-23-2007, 07:18 AM

Originally Posted by Uncle Fester

Jaqui- Starting with a standard FT such as this rx, how many times more expensive would you say is a Franklin bifocal?

Probably a few times higher, but the outcome is much better.

Originally Posted by Uncle Fester

Isn't this the original "executive" bifocal? For Optiboarders education can you please explain how a Franklin bifocal is custom made?

Yes it is the "Original Exec" in all it's beauty. Forget about the FT and just use SV for each half. It is made by grinding the Rx for distance on one lens and the Rx for read on another, cutting them in half and gluing them together (very basic version :) ).

**morinput** · 04-23-2007, 07:30 AM

Why not just order reverse slab ft's in both lenses? Better cosmetics and probably cheaper. I'm just not sure you can get reverses in as little as one Diopter.

**Fezz** · 04-23-2007, 07:54 AM

Originally Posted by morinput

Why not just order reverse slab ft's in both lenses? Better cosmetics and probably cheaper. I'm just not sure you can get reverses in as little as one Diopter.

For Horizontal prism in the distance? Do you men use a prism seg?

**chip anderson** · 04-23-2007, 07:58 AM

Like I said:
Don't use any glue, don't polish the ajoining surfaces (unlens you are going to do this rimless). Just make sure that the ajoining halves fit perfect , are absollutely flat and exactly at 180 degrees. Trust me, the glare from the bottom surface of the top lens and the top surface will be intollerable. Leave a smooth frosted surface and allow the tension of the frame on the lens to hold everything together. Only once twice have I had a patient bring these back to put them back in the frame and each had been subjected to a traumatic incident.

Chip

**Uncle Fester** · 04-23-2007, 09:12 AM

Sorry Chip but never in a million years would I pressure mount a lens for a 10 year old.

**Jacqui** · 04-23-2007, 11:31 AM

Mix a little Tempra paint with the epoxy, it dulls the glare.

**drk** · 04-23-2007, 12:05 PM

I've had a few made the way Chip describes, and it works well. I think they were CR-39 and not poly, but I'd bet trivex would work.

Nonetheless, please call the prescribing OD and see if the reaction is not what I've predicted.

Heck, he may even thank you for the input. He may be able, now, to theorize about his new "yoke prism 'rock'" technique.

Orangy: Examples of far-out stuff: Yoke prism. :) Click my link for a random sample of far-out stuff. I think the respondent is measuring visual abilities in various head positions (vestibular input). As if yoke prism would make them habitually elevate or depress their head? Yeah, I'll believe that one when I see it.

Fester brings up a very, very interesting point. For those behavioralists who wish to "change up" the perceptual environment with yoke prism, all one has to do is prescribe a seg for reading, and they will get variable prism, without the need to prescribe yoke in the first place!