Early Detection of Glaucoma with Objective Pupil Testing

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Craig Thomas, OD discusses how he uses the new EyeKinetix(r) as a screening tool to detect subclinical optic neuropathies, including normal tension glaucoma.

You will learn how to integrate this new technology in a busy practice, and review cases that illustrate the importance of accurately detecting subtle pupillary defects.

A Q&A follows the talk.
 

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Paul Farkas

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hey everyone, show is in about 90 minutes from now (9pm ET), looking forward to seeing everyone there (lots of registrants for this one, it has obviously touched a nerve! ;) )

An outstanding hour. Congratulations Dr Thomas. Adam will place the presentation up for those who missed it.

There were additional questions which will be placed on this topic that Dr Thomas can address.

Konan is also offering a Webinar show discount which Adam will post when he catches his breath.
 

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Just fantastic presentation by Dr. Thomas!! All should watch this lecture and see how Optometry can be practiced
 

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Hey everyone, the archive of the webinar is up, in the first post of the thread.

Thanks again for everyone who turned out, it was great (and congrats to Nancy Davis, who won the Apple Watch!!)

-- ad
 
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AdminWolf

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Caught your breath yet? :)
Not even close! I'm prepping for the NEXT webinar which is next week, and preparing the archives of two prior ones as well.

In terms of the discounts, watch the archive of last night's show, we go over the discounts in the program (with Konan's contact info too.)

thanks
ad
 
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Ed Makler

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In this ODwire.org webinar, Craig Thomas, OD will discuss how he uses the new EyeKinetix® as a screening tool to detect subclinical optic neuropathies, including normal tension glaucoma.

You will learn how to integrate this new technology in a busy practice, and review cases that illustrate the importance of accurately detecting subtle pupillary defects.

** KONAN is offering specials to people who watch the discount and contact them by December 15, 2019 -- watch the webinar for details. The savings are significant.


Adam,

I just ordered my Eyekenitix this afternoon. Craig is a great salesman.
 
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Ronald Bodman

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I received mine last week. Yes, Craig is a great salesman!

Ran it on every patient last three days. It's catching about one patient a day that I would have let sail through here and said "see you in a year".

Yesterday...my receptionist. 42 year old. No subjective concerns . 0.57 eyekinetix reading. 20/20 OU. No VF defects, perfect looking nerves and color testing is good. My OCT is down and I don't have RETeval, etc. Her husband works at the hospital so she is opting to just get an MRI done first instead of planning to take off work to travel to the nearest office that has all the diagnostic equipment I don't have (2 hrs)

Today...29 year old. First exam in 7 yrs, just wanting new glasses. Confrontation fields normal. Father has glaucoma. 0.35 eyekinetix reading OD. Ran VF and a superior defect OD noted and MD -1.6.. Nerves appear healthy. I wouldn't have suspected a thing with this guy

I'm sold. It's as amazing as Craig makes it seem.

Caveats...
I have ran myself on it a few times and the readings have varied from -0.31 to -0.01. If the readings are -0.30 I have my tech run another.

I have not done it yet, but I'm going to have the techs also run color testing right then if the eyekinetix score is abnormal.

It seems to me that dry eye patient readings have to be watched closely (blinking a lot affects the results I feel). Put an artificial tear in their eye before the testing.
 
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Long-term Fluctuation of Relative Afferent Pupillary Defect in Subjects With Normal Visual Function
PlumX Metrics
DOI: https://doi.org/10.1016/S0002-9394(14)70385-X

Purpose
To determine whether the relative afferent pupillary defect (RAPD) remains constant over time in normal subjects.

Methods
Seventeen normal subjects were tested with infrared pupillography and automated perimetry in four sessions over 3 years. The changes in RAPD and visual field asymmetry between testing sessions were compared.

Results
The range of RAPD was 0.0 to 0.3 log unit, and the difference in the mean deviation between the eyes on automated static perimetry was 0 to 3 dB. Eight subjects repeatedly had an RAPD in the same eye. There was no correlation between the RAPD and the visual field asymmetry at the same visit. Changes in the magnitude of the RAPD between any two sessions were typically small (median, 0.08 log unit; 25th percentile, 0.04 log unit; 75th percentile, 0.15 log unit).

Conclusions
Some normal subjects may show a persistent but small RAPD in the absence of detectable pathologic disease. Therefore, an isolated RAPD in the range of 0.3 log unit that is not associated with any other significant historical or clinical finding should probably be considered benign.
 

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Long-term Fluctuation of Relative Afferent Pupillary Defect in Subjects With Normal Visual Function
PlumX Metrics
DOI: https://doi.org/10.1016/S0002-9394(14)70385-X

Purpose
To determine whether the relative afferent pupillary defect (RAPD) remains constant over time in normal subjects.

Methods
Seventeen normal subjects were tested with infrared pupillography and automated perimetry in four sessions over 3 years. The changes in RAPD and visual field asymmetry between testing sessions were compared.

Results
The range of RAPD was 0.0 to 0.3 log unit, and the difference in the mean deviation between the eyes on automated static perimetry was 0 to 3 dB. Eight subjects repeatedly had an RAPD in the same eye. There was no correlation between the RAPD and the visual field asymmetry at the same visit. Changes in the magnitude of the RAPD between any two sessions were typically small (median, 0.08 log unit; 25th percentile, 0.04 log unit; 75th percentile, 0.15 log unit).

Conclusions
Some normal subjects may show a persistent but small RAPD in the absence of detectable pathologic disease. Therefore, an isolated RAPD in the range of 0.3 log unit that is not associated with any other significant historical or clinical finding should probably be considered benign.

Thanks for posting, Lloyd. This is a 23-year old study with 17 subjects -- could you provide something more timely?
 

Jeff Kiener

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I'm sure the human neurological pathways have not evolved substantially since 1996.

A higher N? Sure.

Let's see the white papers on the other side. Or maybe it's been posted by Craig already, but I can't see it?
 

Lloyd Pate

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Thanks for posting, Lloyd. This is a 23-year old study with 17 subjects -- could you provide something more timely?
He posted about the fluctuation in pupil response. I posted a study showing it was normal occurrence. If you are measuring a physiological response, you should know what is normal in order to recognize the abnormal

Why don't you show my post is erroneous instead of attacking me for posting what is available.
 

Frederick Frost

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Long-term Fluctuation of Relative Afferent Pupillary Defect in Subjects With Normal Visual Function
PlumX Metrics
DOI: https://doi.org/10.1016/S0002-9394(14)70385-X

Purpose
To determine whether the relative afferent pupillary defect (RAPD) remains constant over time in normal subjects.

Methods
Seventeen normal subjects were tested with infrared pupillography and automated perimetry in four sessions over 3 years. The changes in RAPD and visual field asymmetry between testing sessions were compared.

Results
The range of RAPD was 0.0 to 0.3 log unit, and the difference in the mean deviation between the eyes on automated static perimetry was 0 to 3 dB. Eight subjects repeatedly had an RAPD in the same eye. There was no correlation between the RAPD and the visual field asymmetry at the same visit. Changes in the magnitude of the RAPD between any two sessions were typically small (median, 0.08 log unit; 25th percentile, 0.04 log unit; 75th percentile, 0.15 log unit).

Conclusions
Some normal subjects may show a persistent but small RAPD in the absence of detectable pathologic disease. Therefore, an isolated RAPD in the range of 0.3 log unit that is not associated with any other significant historical or clinical finding should probably be considered benign.

This is an excellent post and I swear that I’ve seen RAPD‘s disappear and I thought maybe I was wrong the first time when I diagnosed it in the absence of anything else.
 

Lloyd Pate

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Ophthalmology. Author manuscript; available in PMC 2014 Nov 1.

Published in final edited form as:
Ophthalmology. 2013 Nov; 120(11): 10.1016/j.ophtha.2013.04.012.
Published online 2013 Jun 25. doi: 10.1016/j.ophtha.2013.04.012
PMCID: PMC3818414
NIHMSID: NIHMS469046
PMID: 23809274
Accuracy of Pupil Assessment for the Detection of Glaucoma
A Systematic Review and Meta-analysis
Dolly S. Chang, MD, PhD,1,2,3 Li Xu, MD,2 Michael V. Boland, MD, PhD,1,4 and David S. Friedman, MD, PhD1,2,3


The SFT is the most commonly performed test of pupil function in clinical practice. It is quick and quantifiable using neutral density filters. However, the test requires considerable practice to perform reliably, as well as care in its interpretation. An RAPD as small as 0.3 log units can be detected clinically, but the presence of an RAPD implies that significant retinal ganglion cell injury has occurred. In rhesus monkeys, an RAPD measuring 0.6 log units develops after an approximate unilateral loss of 25% to 50% of retinal ganglion cells.45 The introduction of high-resolution IVP has improved our ability to detect even subtle RAPDs. When compared with SFT, pupillography was found to be more sensitive in detecting mild abnormalities, and the identification of an RAPD in persons with glaucoma was generally higher. However, IVP can be abnormal in persons without glaucoma, which may reduce the specificity of the test.

Because tests for an RAPD compare the pupil response between eyes, they cannot detect bilateral or symmetric disease, nor can the results be easily compared between patients.


In conclusion, the available evidence suggests that patients with glaucoma often have an abnormal pupil response to illumination. The measurement of pupil response to light provides an objective test of visual function, which identifies a substantial portion of those with glaucoma in some studies. However, there is insufficient evidence from population-based research assessing pupil response under controlled conditions to support wider use of this approach. Also, an RAPD is relatively nonspecific and may be caused by a number of conditions other than glaucoma. Future studies investigating conditions and confounders affecting pupil responses and methods improving the accuracy of glaucoma detection would be useful.
 

Lloyd Pate

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Eye (Lond). 2015 Oct;29(10):1321-8. doi: 10.1038/eye.2015.106. Epub 2015 Jun 26.
Detection of asymmetric glaucomatous damage using automated pupillography, the swinging flashlight method and the magnified-assisted swinging flashlight method.
Waisbourd M1, Lee B1, Ali MH1, Lu L1, Martinez P1, Faria B1, Williams A1, Moster MR1, Katz LJ1, Spaeth GL1.
Author information
1
Glaucoma Research Center, Wills Eye Hospital, Philadelphia, PA, USA.
Abstract
PURPOSE:
To determine the sensitivity and specificity of various methods of detecting a relative afferent pupillary defect (RAPD) in patients with glaucoma-related diagnoses.

PATIENTS AND METHODS:
Patients underwent RAPD evaluation using the swinging flashlight method (SFM), the magnifier-assisted SFM, and pupillography using the Konan RAPDx. Main outcome measures were sensitivity and specificity of three methods of RAPD evaluation in detecting visual field mean deviation (MD), cup to disc ratio (CDR), disc damage likelihood scale (DDLS), and retinal nerve fiber layer (RNFL) asymmetry.

RESULTS:
Eighty-one consecutive patients from the Wills Eye Hospital glaucoma service were enrolled, 60 with glaucoma and 21 with ocular hypertension or glaucoma suspect. Thirty-one percent of subjects had MD asymmetry>5 dB, 19.7% had CDR asymmetry≥0.20, 26.7% had DDLS asymmetry≥2, and 38.2% had RNFL asymmetry>10 microns. Sensitivity values for pupillography were 93.3% (95% CI, 68.1-99.8) for detecting MD asymmetry, 80.0% (95% CI, 51.9-95.7) for CDR asymmetry, 100.0% (95% CI, 73.5-100.0) for DDLS asymmetry, and 69.2% (95% CI, 38.6-90.9) for RNFL asymmetry. Specificity values were 41.2% (95% CI, 24.7-59.3) for detecting MD asymmetry, 32.8% (95% CI, 21.3-46.0) for CDR asymmetry, 33.3% (95% CI, 18.0-51.8) for DDLS asymmetry, and 42.9% (95% CI, 21.8-66.0) for RNFL asymmetry. Pupillography amplitude score was correlated with MD asymmetry (r2=0.41, P<0.001) and area under the curve was 0.84.

CONCLUSION:
Automated pupillography had higher sensitivity and lower specificity in detecting MD, CDR, DDLS, and RNFL asymmetry. Within the bounds of the cohort tested, this method had limited case-finding ability.
 

AdminWolf

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He posted about the fluctuation in pupil response. I posted a study showing it was normal occurrence. If you are measuring a physiological response, you should know what is normal in order to recognize the abnormal

Why don't you show my post is erroneous instead of attacking me for posting what is available.
This is a larger study from 2016 - it cited the original 1996 paper.

Evaluation of Relative Afferent Pupillary Defect Using RAPDx Device in Patients with Optic Nerve Disease

Neuroophthalmology. 2016 Jun; 40(3): 120–124.
Published online 2016 Apr 14. doi: 10.3109/01658107.2016.1169550


We previously reported the standard values of the amplitude and latency scores in the RAPDx device for evaluating relative afferent pupillary defect (RAPD). Here, we evaluated RAPD in patients with optic nerve disease by using these standard values. Twenty-eight patients with current or previous optic nerve disease were enrolled in this study. Additionally, the data of 84 healthy subjects from our previous report were used as control data. We measured the amplitude and latency scores using RAPDx. We then compared their mean values and the percentages of individuals with standard values within a certain range between the optic nerve disease group and healthy group. Additionally, we evaluated their correlation with visual acuity and the critical flicker fusion frequency in the optic nerve disease group. Both parameters were significantly higher in the optic nerve disease group than in the control group (p < 0.0001). The detection rate of RAPD when using the standard value of amplitude score was 75%. Additionally, both parameters showed a significant correlation with laterality-based differences in visual acuity and critical flicker fusion frequency values in the optic nerve disease group (r = 0.59–0.75, p < 0.001). The amplitude and latency scores determined using RAPDx are useful in evaluating RAPD, particularly the standard value of the amplitude score.


... and from the discussion:

We previously reported the standard values13 of the amplitude and latency scores, the two parameters used in RAPDx to evaluate RAPD. In the present study, we tested the usefulness of these standard values for patients with optic nerve disease. Among patients with optic nerve disease, the percentages of subjects with amplitude and latency scores ≥ 0.50 log units were 75% and 36%, respectively. In contrast, the percentages of subjects with amplitude and latency scores ≥ 0.20 log units were 86% and 68%, respectively. According to previous reports, RAPD by using ND filter occurs in 90% or more of patients with optic nerve disease,15 although Kawasaki et al. reported that RAPD can also be detected in healthy subjects.4 These findings explain the percentages of subjects in the optic nerve disease group who had ≥ 0.20 and ≥ 0.50 log units of the amplitude score in the present study. The ND filter method and amplitude score of RAPDx are similar in terms of analysing the constriction motion. Therefore, our standard value of the amplitude score enabled detection of RAPD. The latency score, however, had detection sensitivity lower than that of the amplitude score. The value of the latency score was previously found to be the same as that of the amplitude score in healthy subjects,13,14 but in the case of patients with optic nerve disease, the value of latency score was smaller than that of the amplitude score. In other words, in terms of the latency score, some patients with optic nerve disease had RAPD equivalent to that in healthy subjects.

Despite the abovementioned differences, both parameters showed significant correlation with the laterality-based differences in visual acuity and CFF values. According to previous reports, in patients with optic nerve disease, the parameters of RAPD examined using the ND filter method showed a significant correlation with the laterality-based differences in visual acuity and CFF.1618 Additionally, Takizawa et al.11 reported results similar to ours using RAPDx. Thus, the amplitude and latency scores in RAPDx enable functional evaluation of visual input, and this device is a useful objective tool. Further, our results also corresponded with those obtained using the conventional quantitative ND filter method. Future studies should investigate disease severity, stage, and type with a greater sample size and involve follow-up measurements of the amplitude and latency scores during treatment of patients with optic nerve disease.

 

Lloyd Pate

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This is a larger study from 2016 - it cited the original 1996 paper.

Evaluation of Relative Afferent Pupillary Defect Using RAPDx Device in Patients with Optic Nerve Disease

Neuroophthalmology. 2016 Jun; 40(3): 120–124.
Published online 2016 Apr 14. doi: 10.3109/01658107.2016.1169550


We previously reported the standard values of the amplitude and latency scores in the RAPDx device for evaluating relative afferent pupillary defect (RAPD). Here, we evaluated RAPD in patients with optic nerve disease by using these standard values. Twenty-eight patients with current or previous optic nerve disease were enrolled in this study. Additionally, the data of 84 healthy subjects from our previous report were used as control data. We measured the amplitude and latency scores using RAPDx. We then compared their mean values and the percentages of individuals with standard values within a certain range between the optic nerve disease group and healthy group. Additionally, we evaluated their correlation with visual acuity and the critical flicker fusion frequency in the optic nerve disease group. Both parameters were significantly higher in the optic nerve disease group than in the control group (p < 0.0001). The detection rate of RAPD when using the standard value of amplitude score was 75%. Additionally, both parameters showed a significant correlation with laterality-based differences in visual acuity and critical flicker fusion frequency values in the optic nerve disease group (r = 0.59–0.75, p < 0.001). The amplitude and latency scores determined using RAPDx are useful in evaluating RAPD, particularly the standard value of the amplitude score.


... and from the discussion:

We previously reported the standard values13 of the amplitude and latency scores, the two parameters used in RAPDx to evaluate RAPD. In the present study, we tested the usefulness of these standard values for patients with optic nerve disease. Among patients with optic nerve disease, the percentages of subjects with amplitude and latency scores ≥ 0.50 log units were 75% and 36%, respectively. In contrast, the percentages of subjects with amplitude and latency scores ≥ 0.20 log units were 86% and 68%, respectively. According to previous reports, RAPD by using ND filter occurs in 90% or more of patients with optic nerve disease,15 although Kawasaki et al. reported that RAPD can also be detected in healthy subjects.4 These findings explain the percentages of subjects in the optic nerve disease group who had ≥ 0.20 and ≥ 0.50 log units of the amplitude score in the present study. The ND filter method and amplitude score of RAPDx are similar in terms of analysing the constriction motion. Therefore, our standard value of the amplitude score enabled detection of RAPD. The latency score, however, had detection sensitivity lower than that of the amplitude score. The value of the latency score was previously found to be the same as that of the amplitude score in healthy subjects,13,14 but in the case of patients with optic nerve disease, the value of latency score was smaller than that of the amplitude score. In other words, in terms of the latency score, some patients with optic nerve disease had RAPD equivalent to that in healthy subjects.

Despite the abovementioned differences, both parameters showed significant correlation with the laterality-based differences in visual acuity and CFF values. According to previous reports, in patients with optic nerve disease, the parameters of RAPD examined using the ND filter method showed a significant correlation with the laterality-based differences in visual acuity and CFF.1618 Additionally, Takizawa et al.11 reported results similar to ours using RAPDx. Thus, the amplitude and latency scores in RAPDx enable functional evaluation of visual input, and this device is a useful objective tool. Further, our results also corresponded with those obtained using the conventional quantitative ND filter method. Future studies should investigate disease severity, stage, and type with a greater sample size and involve follow-up measurements of the amplitude and latency scores during treatment of patients with optic nerve disease.
That study addresses patients with optic nerve disease not normal patients.
 

AdminWolf

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That study addresses patients with optic nerve disease not normal patients.
they used control data from 84 healthy people as well (see the tables.)
 

Lloyd Pate

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This is a larger study from 2016 - it cited the original 1996 paper.

Evaluation of Relative Afferent Pupillary Defect Using RAPDx Device in Patients with Optic Nerve Disease

Neuroophthalmology. 2016 Jun; 40(3): 120–124.
Published online 2016 Apr 14. doi: 10.3109/01658107.2016.1169550


We previously reported the standard values of the amplitude and latency scores in the RAPDx device for evaluating relative afferent pupillary defect (RAPD). Here, we evaluated RAPD in patients with optic nerve disease by using these standard values. Twenty-eight patients with current or previous optic nerve disease were enrolled in this study. Additionally, the data of 84 healthy subjects from our previous report were used as control data. We measured the amplitude and latency scores using RAPDx. We then compared their mean values and the percentages of individuals with standard values within a certain range between the optic nerve disease group and healthy group. Additionally, we evaluated their correlation with visual acuity and the critical flicker fusion frequency in the optic nerve disease group. Both parameters were significantly higher in the optic nerve disease group than in the control group (p < 0.0001). The detection rate of RAPD when using the standard value of amplitude score was 75%. Additionally, both parameters showed a significant correlation with laterality-based differences in visual acuity and critical flicker fusion frequency values in the optic nerve disease group (r = 0.59–0.75, p < 0.001). The amplitude and latency scores determined using RAPDx are useful in evaluating RAPD, particularly the standard value of the amplitude score.


... and from the discussion:

We previously reported the standard values13 of the amplitude and latency scores, the two parameters used in RAPDx to evaluate RAPD. In the present study, we tested the usefulness of these standard values for patients with optic nerve disease. Among patients with optic nerve disease, the percentages of subjects with amplitude and latency scores ≥ 0.50 log units were 75% and 36%, respectively. In contrast, the percentages of subjects with amplitude and latency scores ≥ 0.20 log units were 86% and 68%, respectively. According to previous reports, RAPD by using ND filter occurs in 90% or more of patients with optic nerve disease,15 although Kawasaki et al. reported that RAPD can also be detected in healthy subjects.4 These findings explain the percentages of subjects in the optic nerve disease group who had ≥ 0.20 and ≥ 0.50 log units of the amplitude score in the present study. The ND filter method and amplitude score of RAPDx are similar in terms of analysing the constriction motion. Therefore, our standard value of the amplitude score enabled detection of RAPD. The latency score, however, had detection sensitivity lower than that of the amplitude score. The value of the latency score was previously found to be the same as that of the amplitude score in healthy subjects,13,14 but in the case of patients with optic nerve disease, the value of latency score was smaller than that of the amplitude score. In other words, in terms of the latency score, some patients with optic nerve disease had RAPD equivalent to that in healthy subjects.

Despite the abovementioned differences, both parameters showed significant correlation with the laterality-based differences in visual acuity and CFF values. According to previous reports, in patients with optic nerve disease, the parameters of RAPD examined using the ND filter method showed a significant correlation with the laterality-based differences in visual acuity and CFF.1618 Additionally, Takizawa et al.11 reported results similar to ours using RAPDx. Thus, the amplitude and latency scores in RAPDx enable functional evaluation of visual input, and this device is a useful objective tool. Further, our results also corresponded with those obtained using the conventional quantitative ND filter method. Future studies should investigate disease severity, stage, and type with a greater sample size and involve follow-up measurements of the amplitude and latency scores during treatment of patients with optic nerve disease.
Your study posted says "our results also corresponded with those obtained using the conventional quantitative ND filter method." So, the fancy machine is no better than me with my ND filters.
 

AdminWolf

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Your study posted says "our results also corresponded with those obtained using the conventional quantitative ND filter method." So, the fancy machine is no better than me with my ND filters.

Well, not exactly so -- I don't doubt you're good at it. But using an ND filter is ultimately subjective (see below, from the American Academy of Ophthalmology's web site). The idea behind Eyekinetix is that the test is repeatable, objective, and fast. Watch the webinar -- Dr. Thomas has his staff perform the test in a minute or two.

https://eyewiki.org/Relative_Afferent_Pupillary_Defect

Various techniques have been described to quantify or measure APDs. These include the use of neutral density filters [10], cross-polarized filters [11], and subjective grading based on the amount of initial contraction and subsequent re-dilation of each pupil as the light is swung [12]. Although these techniques have been shown to be effective and accurate, a number of factors influence the validity, variability, and reliability of such measurements. These techniques, although objective in their quantification, are unfortunately subjective in their endpoint. clinical grading in plus scale and quantification with various filters techniques are comparable.
 

Lloyd Pate

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Well, not exactly so -- I don't doubt you're good at it. But using an ND filter is ultimately subjective (see below, from the American Academy of Ophthalmology's web site). The idea behind Eyekinetix is that the test is repeatable, objective, and fast. Watch the webinar -- Dr. Thomas has his staff perform the test in a minute or two.

https://eyewiki.org/Relative_Afferent_Pupillary_Defect

Various techniques have been described to quantify or measure APDs. These include the use of neutral density filters [10], cross-polarized filters [11], and subjective grading based on the amount of initial contraction and subsequent re-dilation of each pupil as the light is swung [12]. Although these techniques have been shown to be effective and accurate, a number of factors influence the validity, variability, and reliability of such measurements. These techniques, although objective in their quantification, are unfortunately subjective in their endpoint. clinical grading in plus scale and quantification with various filters techniques are comparable.
But the results with it will also vary because of the normal fluctuation in pupil response.
 

Paul Farkas

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But the results with it will also vary because of the normal fluctuation in pupil response.

These arguments creates head spinning and eyes glazing.:eek:

Botton line...

If UHCO placed the EyeKinetix unit in your clinic, would you use it or use the conventional quantitative ND filter?
 
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Paul Farkas

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Adam,

I just ordered my Eyekenitix this afternoon. Craig is a great salesman.

What makes a great salesman are two important quaklities...

They have the sizzle...a marvelous presentation

And the stick...the system works.
 
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Lloyd Pate

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These arguments creates head spinning and eyes glazing.:eek:

Botton line...

If UHCO placed the EyeKinetix unit in your clinic, would you use it or use the conventional quantitative ND filter?
It depends on which one worked the best after an evaluation period. The sales pitch is distorting its utility.
 

AdminWolf

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Shouldn't the adaptation of a medical device be based on scientific study not a great salesman?

Obviously, the science needs to be there. But industry also plays an important role in pushing forward with new technology. If we waited for academia for tech breakthroughs, half of us would probably be dead.

I'll ask Konan and LCT for more whitepapers that we can post here -- the more data, the better!
 

AdminWolf

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Just a few more points, and then I'm done!

1. Pupillary testing is often not done at all, because docs start out looking hard, never find anything, and give up looking.
(In med school I remember doing the swinging flashlight on rounds in 10 seconds flat and writing "PERRL" more times than I can count -- but unless the patient had a grossly blown pupil, I'm certain I missed some asymmetry.)

2. If adding technology that can be delegated to a tech (ie, take up less of the doctor's time), results in pupils being checked routinely, accurately, quickly and objectively, how can that be a bad thing?

I get in your case Lloyd you're at a university, you want to show students how to do everything manually (and your caseload is probably such that you don't see 40+ patients a day every day).

But in the world outside of academia, consider that most docs don't do a thorough job checking the pupils (if they do it at all). Heck, in one of the cases LCT reviews, the patient was under the care of a board-certified neurologist who MISSED the RAPD -- despite probably doing dozens swinging flashlights every day for years.

3. The natural variability in pupil responses doesn’t change with EyeKinetix or the swinging flashlight test. Therefore, assuming you are very good at the flashlight test, and use ND filters, you are just as likely to have a false positive or false negative with either method.
 
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h.c. jang

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I received mine last week. Yes, Craig is a great salesman!

Ran it on every patient last three days. It's catching about one patient a day that I would have let sail through here and said "see you in a year".

Yesterday...my receptionist. 42 year old. No subjective concerns . 0.57 eyekinetix reading. 20/20 OU. No VF defects, perfect looking nerves and color testing is good. My OCT is down and I don't have RETeval, etc. Her husband works at the hospital so she is opting to just get an MRI done first instead of planning to take off work to travel to the nearest office that has all the diagnostic equipment I don't have (2 hrs)

Today...29 year old. First exam in 7 yrs, just wanting new glasses. Confrontation fields normal. Father has glaucoma. 0.35 eyekinetix reading OD. Ran VF and a superior defect OD noted and MD -1.6.. Nerves appear healthy. I wouldn't have suspected a thing with this guy

I'm sold. It's as amazing as Craig makes it seem.

Caveats...
I have ran myself on it a few times and the readings have varied from -0.31 to -0.01. If the readings are -0.30 I have my tech run another.

I have not done it yet, but I'm going to have the techs also run color testing right then if the eyekinetix score is abnormal.

It seems to me that dry eye patient readings have to be watched closely (blinking a lot affects the results I feel). Put an artificial tear in their eye before the testing.
Variability of 0.31 to 0.01 is insane. And an MRI because 0.57 with no other signs and symptoms? If the MRI shows something, great. What if it came out clean? What would she do next?
 
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Lloyd Pate

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Variability of 0.31 to 0.01 is insane. And an MRI because 0.57 with no other signs and symptoms? If the MRI shows something, great. What if it came out clean? What would she do next?
What is the diagnosis to order an MRI? That is not how medicine works. You must have a tentative diagnosis and then order a test to confirm or exclude your diagnosis.
 

Jeff Kiener

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You must have a tentative diagnosis and then order a test to confirm or exclude your diagnosis.
Micro-afferent pupillary defect, but of course.

Please rule out glioblastoma, meningioma, pheochromocytoma, glaucoma, multiple sclerosis, epilepsy, senile dementia, orbital mass, blue light damage, and anything else.
 

Joe DiGiorgio O.D.

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Micro-afferent pupillary defect, but of course.

Please rule out glioblastoma, meningioma, pheochromocytoma, glaucoma, multiple sclerosis, epilepsy, senile dementia, orbital mass, blue light damage, and anything else.

So are you saying that a RAPD is not specific to glaucoma? So is it an indication of MRI, MRA, cerebral angiogram, etc. Does it have any useful indications for other disciplines besides optometry?

What is a reasonable workup for the patient with RAPD?


Conditions Leading to a RAPD
  • Optic nerve disorders: Unilateral optic neuropathies are common causes of RAPD.
  • Demyelination Optic neuritis: Even very mild optic neuritis with a minimal loss of vision can lead to a very strong RAPD.
  • Ischemic optic neuropathies: These include arteritic (Giant Cell Arteritis) and non-arteritic causes. Usually there will be a loss of vision or a horizontal cut in the visual field.
  • Glaucoma: While glaucoma normally is a bilateral disease, if one optic nerve has particularly severe damage, an RAPD can be seen.
  • Traumatic optic neuropathy: This includes direct ocular trauma, orbital trauma, and even more remote head injuries which can damage the optic nerve as it passes through the optic canal into the cranial vault.
  • Optic nerve tumor: This is a rare cause and includes primary tumors of the optic nerve (glioma, meningioma) or tumors compressing the optic nerve (sphenoid wing meningioma, pituitary lesions, etc.).
  • Compressive optic neuropathy with or without orbital disease: This could include compressive damage to the optic nerve from thyroid related orbitopathy (compression from enlarged extraocular muscles in the orbit), orbital tumors, or vascular malformations.
  • Radiation optic nerve damage
  • Hereditary optic neuropathies, such as Leber's optic neuropathy (usually eventually bilateral) and other inheritable optic neuropathies.
  • Other optic nerve infections or inflammations: Cryptococcus can cause a severe optic nerve infection in the immunocompromised. Sarcoidosis can cause inflammation of the optic nerve. Lyme disease can affect the optic nerve.
  • Optic atrophy status: post papilledema - This is usually bilateral.
  • Post Surgical damage to the optic nerve: This could include damage following retrobulbar anesthesia; damage following orbital hemorrhage related to eye, orbital, sinus, or plastic surgery; damage following neurosurgical procedures such as pituitary tumor resection; and damage related to migration of an orbital plate after surgery to correct a blow-out fracture.

Retinal Causes of a Relative Afferent Pupillary Defect

Again, symmetrically bilateral retinal disease will not show a RAPD. Usually, retinal disease has to be quite severe for an RAPD to be clinically evident.

  • Ischemic retinal disease: Causes include ischemic central retinal vein occlusion, central retinal artery occlusion, severe ischemic branch retinal or arterial occlusions, severe ischemic diabetic or sickle-cell retinopathy.
  • Ischemic ocular disease (Ocular ischemic syndrome): This usually arises from obstruction of the ophthalmic or carotid artery on one side.
  • Retinal detachment: A RAPD can often be seen if the macula is detached, or if at least two quadrants of retina are detached.
  • Severe macular degeneration: If unilateral and severe, a RAPD can be seen. Usually the visual acuity would be less than 20/400.
  • Intraocular tumor: Retinal and choroidal tumors including melanoma, retinoblastoma, and metastatic lesion could lead to a RAPD if severe.
  • Retinal infection: Cytomegalovirus, herpes simplex, and other causes of retinitis can lead to a RAPD if there is extensive disease.
Other Causes of a Relative Afferent Pupillary Defect
  • Amblyopia: If severe, can lead to a relative afferent pupillary defect. Usually the visual acuity would be 20/400, or worse.
  • Cerebral vascular disease: Usually, it is an optic nerve disorder that leads to a RAPD, rather than an optic tract or visual cortex disorder. However, there tends to be a higher percentage of crossed vs. uncrossed nerve fibers at the optic chiasm. Thus, in a patient with a homonymous hemianopia from an optic tract disorder, an RAPD could be seen in the eye with the temporal visual field defect. The nasal retina serves the temporal visual field, and these are the fibers that would cross at the chiasm [3].
https://eyewiki.org/Relative_Afferent_Pupillary_Defect


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Possible Diagnoses

Some articles suggest that an RAPD can occur as a result of the light scatter caused by a very dense asymmetric cataract. Clinically, however, a dense cataract should never be used to explain the presence of an RAPD.7


The presence of an RAPD most often indicates relative optic nerve disease.8 An amblyopic eye may present with a mild RAPD, but you must first rule out optic nerve pathology.


Also, an RAPD can be caused by significant retinal pathology. For instance, a large macular scar, a significant retinal detachment and a central retinal artery or ischemic central retinal vein occlusion can result in an afferent pupillary defect.1-3

I suggest taking a stepwise approach when a patient presents with an RAPD. Specifically:

Ask if the patient is aware of changes in vision. If so, are these changes acute or gradual? An acute optic neuropathy or retinal detachment would be associated with sudden vision loss, while gradual vision loss might support the existence of a compressive lesion.

Elicit significant ocular and medical history. Does the patient have a history of vascular disease, cancer, auto-immune disease, recent infections or trauma?

Carefully examine the patient, and pay special attention to the retina and optic nerve. Optic nerve findings can be subtle or non-existent. For instance, a relatively normal appearing nerve might be present in a retrobulbar optic neuritis. That is why color vision testing and perimetry are so important to the evaluation.


The need to refer for further testing depends on the case. If the patients history and retinal examination do not offer an obvious explanation for the APD, one must assume that a condition affecting the optic nerve or optic tract is causing it. An immediate visual field and color vision test should be performed.


Depending on the condition, the patient may need to be referred for emergent neuro-imaging and laboratory testing. For example, an individual who presents with an RAPD as a result of swollen optic nerve and a history of leukemia, would require emergent imaging and radiation treatment if the swollen nerve represented a leukemic infiltrative optic neuropathy.


In the absence of vascular risk factors, or in patients younger than 40, infectious, inflammatory, infiltrative or medication-induced optic neuropathy must always be ruled out. For instance, optic neuropathy induced by Viagra (sildenafil, Pfizer) is well documented.14 Additionally, amiodarone, a medication used to manage cardiac arrhythmia, has also been implicated.15,16


You must rule out GCA in patients older than 56. This requires emergent sedimentation rate and C-reactive protein tests. Optic neuritis, which is also an acute event, is usually retrobulbar, and more commonly occurs in patients younger than 50; patients mostly present with pain on eye movements. So, any patients who presents with optic nerve disease that cannot be attributable to typical NAION must be worked up and imaged urgently.


When a patient presents with a relative afferent pupillary defect, a correct differential diagnosis of your clinical signs and symptoms can help steer you toward a timely and appropriate referral. The key is not to panic. Let a case history, examination and ancillary testing help you determine how to handle a patient who presents with an APD.

Dr. Canellos practices with the New York Harbor VA Health Care System at the Brooklyn and St. Albans facilities. He is an adjunct assistant clinical professor at the State University of New York State College of Optometry.

https://www.reviewofoptometry.com/article/back-to-the-basics-part-5-my-patient-has-an-rapd-now-what


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Jeff Kiener

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Everybody understands the value of pupillary testing and that is not in question here.
I'd like you to lay that out for me, Fred.

I'm going to ask some questions, and then feel free to rebut. I won't block you for your views.

Is this device for routine screening or for diagnostics, or both?

What exactly does it do? Quantify pupil size in various illumination (or a standard illumination) with a standard spectum? Because that would be job one.

Clearly it measures pupil response size, and then escape over a period of time (probably multiple measurements over a few seconds at most).

It probably has two separate LED light sources that alternate.

I'm sure there is such a thing as "short-term fatigue" whereby the retina adapts and lowers it's sensitivity due to the luminosity, so that the overall pupil response (positive and negative) decreases, but presumably the difference persists.

In fact, I would probably zap the subjects eyes with an equal luminousity PREMEASUREMENT in order to equalize the retinal sensitivity. We know retinas have independent adaptation.

Statistically, as well, baseline pupil area should be accounted for; anisocorias would probably affect total light delivered to the retina.

It would be interesting to know what wavelenghts/spectrum was chosen and why. I would also be interesting to know if wavelength-specific light would yield new information (blue loss, red loss, etc., like Sita SWAP). (If it's that sensitive, the relatively lower luminiousity of the narrow-spectrum stimulus could be overcome.) Who knows? That approach may lend specificity to the testing protocol.
 
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Frederick Frost

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I'd like you to lay that out for me, Fred.

I'm going to ask some questions, and then feel free to rebut. I won't block you for your views.

Is this device for routine screening or for diagnostics, or both?

What exactly does it do? Quantify pupil size in various illumination (or a standard illumination) with a standard spectum? Because that would be job one.

Clearly it measures pupil response size, and then escape over a period of time (probably multiple measurements over a few seconds at most).

It probably has two separate LED light sources that alternate.

I'm sure there is such a thing as "short-term fatigue" whereby the retina adapts and lowers it's sensitivity due to the luminosity, so that the overall pupil response (positive and negative) decreases, but presumably the difference persists.

In fact, I would probably zap the subjects eyes with an equal luminousity PREMEASUREMENT in order to equalize the retinal sensitivity. We know retinas have independent adaptation.

Statistically, as well, baseline pupil area should be accounted for; anisocorias would probably affect total light delivered to the retina.

It would be interesting to know what wavelenghts/spectrum was chosen and why. I would also be interesting to know if wavelength-specific light would yield new information (blue loss, red loss, etc., like Sita SWAP). (If it's that sensitive, the relatively lower luminiousity of the narrow-spectrum stimulus could be overcome.) Who knows? That approach may lend specificity to the testing protocol.
Jeff,

I have no first-hand knowledge of the instrument as I have not used it or even seen it in person. When I use as below. What I simply meant by my comment was there is a value to pupillary testing whether is done manually or with an automated instrument and that should not be in question.

Whether we find an RAPD manually or with this instrument it is going to require further investigation.

I can see this having a value in busy practices saving time and eliminating Tech errors if they are the ones checking pupils in the practice.
271D580B-8A31-44AF-ABAA-58D68493F96B.jpeg
 
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Mike Ware OD

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There is obviously some value to this device but the cost seems a bit high for a pretesting device. I couldn't justify the cost when my Optovue has a screener function that can be done in seconds and is more specific for glaucoma.
 
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Joe DiGiorgio O.D.

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There is obviously some value to this device but the cost seems a bit high for a pretesting device. I couldn't justify the cost when my Optovue has a screener function that can be done in seconds and is more specific for glaucoma.

That goes back to my thought about getting a $6,000 Matrix as part of pretest which would seem to be a good way to “screen” for ON defects.
 

Lloyd Pate

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View attachment 24237
Jeff,

I have no first-hand knowledge of the instrument as I have not used it or even seen it in person. When I use as below. What I simply meant by my comment was there is a value to pupillary testing whether is done manually or with an automated instrument and that should not be in question.

Whether we find an RAPD manually or with this instrument it is going to require further investigation.

I can see this having a value in busy practices saving time and eliminating Tech errors if they are the ones checking pupils in the practice. View attachment 24237
I was knighted with a gift ND bar like that by a neuro-ophth many moons ago.
 
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