An autorefractor as good as retinoscopy?

[ilanh]

This topic came up on another thread regarding the art of refraction. I was wondering if any one out there was very impressed by any autorefractors? I own two of them and have played with many others in the past. I am singularly unimpressed. I have great confidence in my retinoscopy and in my refracting skills, but it takes too much time. I have refracting techs who may benefit from an AR that at least starts them out as accurately as possible. It seems to me that excess or insufficient sphere is never the problem (it can always be adjusted). However, misleading cylinder power or axis can lead a refraction down a completely wrong path. I even demo'd a Marco epic "30 second refraction" machine and found that my 30 seconds of retinoscopy was closer every time. I would love to hear from people who have actually compared the initial results of an AR to an accurate refraction with retinoscopy, phoropter and trial framing.

[npdr]

Here in lies the justification "... I have great confidence in my retinoscopy and in my refracting skills, but it takes too much time. .."

Ergo, autorefractor.

[IndianaOD]

Could just take the time to actually take care of your patients! I am impressed if you are an ophthalmologist who can actually use a retinoscope! Kudos :cheers:

[harry888]

the clarity/sharpness/dullness of the retinoscopic reflex immedicately alerts me to opacities somewhere in the pathway to the retina.

Saves time.

Harry

[Borysko]

Could just take the time to actually take care of your patients! I am impressed if you are an ophthalmologist who can actually use a retinoscope! Kudos :cheers:

Sure, that's great--only I can use a retinoscope and the OP clearly said he/she doesn't want to take the time to do it!
You get kudos for refusing to do something as long as you CAN do it?

[nickrock]

I don't believe that an autorefraction will ever be as good as retinoscopy. For one thing, it is hard to plug in your AR when you are on medical mission in the outback of Australia, you can't always control accommodation with an AR, and ret is great if you have a non-ambulatory patient or hospital inpatient.

[Oedema]

Teach your techs retinoscopy?? I've worked in a practice were some of the tech were able to do this, but implementing the training and ensuring that you have good techs that will have and interest, and have an interest in doing a good job could be a PITA.

[Yeap]

[QUOTE=npdr;307198]Here in lies the justification "... I have great confidence in my retinoscopy and in my refracting skills, but it takes too much time. .."


Doubt when you saying this.. if you able to do it well it actually save you lots time, i will say it maybe faster than Autorefraktor..

you can just take the Autorefractor result as a guideline. if you really want to save time then train your assisstant or any technician to do that for you.

[Darryl Meister]

I don't know that autorefractors will ever replace a complete subjective refraction by a skilled clinician, which is more or less the "gold standard." But I am a bit surprised that you find autorefraction noticeably less accurate than retinoscopy, which always seemed to me to involve a lot of "eyeballing" of the reflex.

[fjpod]

The original question was, is an autorefractor as good as retinoscopy. Having done thousands of both,... sometimes it's better and sometimes it's worse. An autorefractor can save time and a good clinician will know when it is unreliable, and pull out the retinascope.

I scope every new patient. I'll also do it if I see that the auto-refractor is finding a large change from the last visit.

[Strab]

We are an Ophthalmologist practice and our techs use an AR for all of our patients. Most of the time it seems to work well but there is a difference in accuracy from tech to tech and patient to patient. Some techs don't pay attention to the previous script and the pt. ends up with changes that are substantially incorrect. Also, the AR does not pick up on the need for even a significant amount of prism. I am the office Optician so I see all the remakes that get done and I can tell you most if not all doctor remakes are a result of the AR not being used correctly or the pt.'s rx not getting double checked by a complete subjective refraction. I am not against it's use, I just believe it should be a supplement or guide and not the primary source for refracting.

[hipoptical]

A standard refraction is subjective (for the most part). An autorefractor is objective. Wouldn't the better question be "which is more desirable" rather than trying to compare the two as if they were the same thing? You could have the best, most accurate machine that is technically 100% correct every time, but if the patient doesn't like what he/she sees, then you always go with what the patient prefers, right? (I've never known of a time when the technically correct Rx was given instead of the patient's choice.)
I will say that I would love it autorefractors were good enough. I just don't think we're there, yet. The super-fabulous machine from Izon is supposed to be better than sliced bread. Does it have a place in this discussion?

[Darryl Meister]

Keep in mind that autorefractors and similar diagnostic tools cannot currently replace a complete subjective refraction. Regardless of the accuracy of the ocular refraction, these devices do not perform binocular balancing, determine corrections for binocular vision anomalies, etcetera.

[ESuffolkIDoc]

An autorefractor generally uses a source and algorithms to "model" the refractive state of the eye. It will generally have too much cyl for many pts and be affected by pts accomodation.

With a retinoscope , you are oberving the optical system dynamically and can see if the pt is over accomodating etc. It is more interactive and you can observe those with tendencies to overaccomodate etc.

A subjective refraction will end at a point where you have solved the patients issues they have presented to you with the proper sph, cyl axis and prism as needed. it should take into account what the patient is used to, the way the patient processes vision and perception, abnormal muscle posturing etc.

They are all different. I used AR as guide, retinoscope when something seems "fishy" and spend most of the time on the subjective including verticle and horizontal muscle postures, the amount of cyl that seems to give pt the best "response" and the same for sph. That is the art.

[sunsign]

Dear All,
It is nice to know that the debate of AR Vs retino is still on. I do face this every day in our practise . there are some ophthalmologist who insists on AR and Rx based on AR readings including the full cyl correction. i am skeptical about full correction based on AR. the Ophthalmologist are not very sure of full correction based on retino.

sunsign

[chip anderson]

Just a semi-related question: How much does it actually cost (maintence, electricity, purchase cost per lifetime useage, printer paper, ink, etc. ) to
use an autorefractor per patient?

Chip

[Borysko]

Just a semi-related question: How much does it actually cost (maintence, electricity, purchase cost per lifetime useage, printer paper, ink, etc. ) to
use an autorefractor per patient?

Chip

I assume the question is rhetorical, and the answer is--TOO MUCH!

[chip anderson]

Question is quite litteral. I assume there is some cost involved as I am told the maintenance and calibration on the auto surgical machines (lasic) is quite expensive. Maybe auto refractors are similar, and maybe it's only about 2 cents a patient, I have no clue.

Chip

[sunsign]

reg your original question of how much will an AR cost , it purely depends on what model you want and what you do with it , the basic model in India could cost around 3000$ and the hihg end (the one whihc takes into account the accommodative status of the patients eye )could cost 6000$. the operating cost of maintainence could vary few dollars to few hundreds

Sunsign

[ilanh]

Personally, I rarely bother with an AR (and I own several). This is not to say that I am able to retinoscope every single patient. I have many patients with cloudy media and poor retinoscopic reflexes. In such cases, one advantage of the AR is that it can at least give you the axis and power of astigmatism by simply measuring the cornea. You can then dial that into the phoropter and proceed from there. Also, there are some occasions when I get confused by the light reflex (excessively large pupils etc) and may consult with an AR in such cases. However, in about 95% of the time I don't bother with an AR and rely exclusively on my retinoscopy. If I could find an AR which is as reliable as my scoping, then I would have the techs do an AR on every patient and I would start my subjective refraction from that beginning point. It would save time in the long run.

[snowmonster]

Retinoscopy can be a lot of fun on media opacities. I've worked in ophthalmology practices in the past with a bad AR machine and lazy refracting technicians and know what you're up against.

I've worked around a few different AR machines in the past. The Zeiss one wasn't all that great, overminused quite frequently. We demo'd a Reichert and it also did the same thing, was great on high myopes and presbyopes but that's about it.

I've worked with two separate Topcon KR-8800's and they are quite good, usually under-minuses/over-pluses by 0.25 diopters, the cylinder amount is usually quite accurate, the axis is more the variable. But it's almost always a good starting point for a refraction. The keratometry readings are also quite accurate. If something seems odd with the refraction process within the first 30 seconds, I'll pick up the retinoscope (which I'm also good at) but that doesn't need to happen all that often.

Recently, I got interested in the wavefront machines. We demo'd a Marco unit which was not accurate at all. The rep ordered another one in which was equally bad. I was surprised by this, considering the technology. We quickly put our Topcon ARK back online. I might still try the newer Topcon KR-9000PW which is a wavefront machine though despite this history. We're a Topcon office, ARK, NCT, fundus camera and slit lamp cameras. Everything just "works."

BTW, I don't work for Topcon.

[sunsign]

Retinoscopy can be a lot of fun on media opacities. I've worked in ophthalmology practices in the past with a bad AR machine and lazy refracting technicians and know what you're up against.

I've worked around a few different AR machines in the past. The Zeiss one wasn't all that great, overminused quite frequently. We demo'd a Reichert and it also did the same thing, was great on high myopes and presbyopes but that's about it.

I've worked with two separate Topcon KR-8800's and they are quite good, usually under-minuses/over-pluses by 0.25 diopters, the cylinder amount is usually quite accurate, the axis is more the variable. But it's almost always a good starting point for a refraction. The keratometry readings are also quite accurate. If something seems odd with the refraction process within the first 30 seconds, I'll pick up the retinoscope (which I'm also good at) but that doesn't need to happen all that often.

Recently, I got interested in the wavefront machines. We demo'd a Marco unit which was not accurate at all. The rep ordered another one in which was equally bad. I was surprised by this, considering the technology. We quickly put our Topcon ARK back online. I might still try the newer Topcon KR-9000PW which is a wavefront machine though despite this history. We're a Topcon office, ARK, NCT, fundus camera and slit lamp cameras. Everything just "works."

BTW, I don't work for Topcon.

Dear Snowmonster,
We do have Topcon AutoKR, unlike you our experiance show that it overminuses and under plus the refraction. infact i had a thread started on optimum correction of myopes because we found our experance with AR to be over minused whereas the ophthalmologist insists on giving rx based on AR. like you said we do have topcon fundus camera which simply works. their slit lamp SL3c is also fine (only thing the cost of the slit lamp bulbs is too much )

sunsign

[chip anderson]

No one has mentioned that if the machine gets the cylinder right and only over minuses. One can always over refract the result with plus spheres until this is ballanced.
As to the autorefractor being as good or better than the retinascope, depends on who is using the retinascope. I've seen some that would get far better results if the autorefractor did all the work. Others that seldom miss anything with a retinascope.
Also might be effected by how much time the person using the retinascope was willing to use on each patient.

Chip

[snowmonster]

Sunsign - how old/what model is that Topcon ARK machine? Just curious.

[Oedema]

Personally, I rarely bother with an AR (and I own several). This is not to say that I am able to retinoscope every single patient. I have many patients with cloudy media and poor retinoscopic reflexes. In such cases, one advantage of the AR is that it can at least give you the axis and power of astigmatism by simply measuring the cornea. You can then dial that into the phoropter and proceed from there. Also, there are some occasions when I get confused by the light reflex (excessively large pupils etc) and may consult with an AR in such cases. However, in about 95% of the time I don't bother with an AR and rely exclusively on my retinoscopy. If I could find an AR which is as reliable as my scoping, then I would have the techs do an AR on every patient and I would start my subjective refraction from that beginning point. It would save time in the long run.

I don't think you'll ever truly find an AR that you're happy with/trust. I prefer to do retinoscopy, but given the information from VA's and habitual correction I often feel that objective data like AR/Retinoscopy is not really necessary.

However, the techs were I work always do the AR, so I rarely find myself doing retinoscopy unless something doesn't add up between all the data at hand. I don't think I'll ever be able to trust the AR and give up on retinoscopy, I find its helpful to see the reflex, and my findings are always spot on unless there is significant media opacity/really small pupils - these are the only cases where I really really appreciate the AR.

Tip for the large pupils: ignore the reflex in the periphery, just look at the central reflex.