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Medical Forum / General / Vision / January 2007Question for Dr. Stacy Regarding Floaters
Dr. Stacy, In a recent discussion regarding floaters (which I unfortunately deleted), I believe you stated that floaters would have to be VERY bad before a vitrectomy might be justified. I have what I consider to be very bad floaters for the past 7 years, and have been wrestling with that question over that time. What criteria does one use to determine whether to seek a vitrectomy? In my case, I have large globs of "mud" that obscure a large portion of my vision. Reading is very difficult, for example, not only because so much of a line of print is obscured, but because the contrast between the print and background is poor. It is also not an exaggeration to say that the globs torment me almost all of the time and seem to cause persistent eye strain and tearing. Yet I have something close to 20/20 on an eye chart and no eye disease according to recent dilated eye exams. What are your thoughts as to what criteria justify vitrectomy? Thank you for your comments. I would also be interested in any additional opinions from other readers. Charles > In a recent discussion regarding floaters (which I unfortunately deleted), I > believe you stated that floaters would have to be VERY bad before a > vitrectomy might be justified. Google is your friend. > and tearing. Yet I have something close to 20/20 on an eye chart and no eye > disease according to recent dilated eye exams. What are your thoughts as to > what criteria justify vitrectomy? 20/20 on the eye chart is a first cut. It isn't the final answer. > I would also be interested in any additional opinions from other readers. What does your doctor advise? ObOT: I had a vitrectomy about a year ago. My doctor said that as a side effect, I would lose the floaters. Charles, if I were in your situation, I'd be setting up a pre-surgery consultation with my retinal surgeon rather than seeking opinions on the internet. I had a vitrectomy about a year ago to remove a macular pucker. The worst consequence of the surgery was the development of a cataract in the surgical eye. (I've read that it's the result of the lens' exposure to oxygen.) Unless you are at high risk for retinal detachment, I believe that the a vitrectomy is quite safe if done by a competent retinal surgeon. And with the new 25-gauge "sutureless" equipment, recovery is very rapid. One surgeon wrote that the day after the vitrectomy, it's frequently difficult to tell which of the patient's eyes had the surgery. Best of luck! Good advice, but since he's asking, I'll venture that he might be a candidate for it, especially if he is over age 50, since the subsequent cataract surgery that is certain to follow if he hasn't yet had it is sort of a blessing in disguise. I'll bet he's 20/20 only part of the time, and when the goop is in the way he may drop to worse than 20/100 or so in the affected eye. w.stacy, o.d. >Charles, if I were in your situation, I'd be setting up a pre-surgery >consultation with my retinal surgeon rather than seeking opinions on [quoted text clipped - 11 lines] > > >Dr. Stacy, > [quoted text clipped - 18 lines] > >I would also be interested in any additional opinions from other readers. First of all, realize a vitrectomy is not "minor surgery". Next, realize that anytime the eye gets "cracked open" there is real risk of a microbial infection inside the eye (i.e., endophthalmitis). I have never referred a patient to a retinal surgeon for an evaluation for vitrectomy to get rid of floaters. However, my criteria for a "20/20 patient" would be the patient would to have to be absolutely miserable and thoroughly understand the risks/benefits of the procedure. From your description (i.e., "torment") above, you may be better off being prescribed an antidepressant than a vitrectomy. And although some others have said recovery from a vitrectomy is minimal, there are other times after a vitrectomy that your eye feels like someone played pinball with it. > >I would also be interested in any additional opinions from other readers. > [quoted text clipped - 13 lines] > minimal, there are other times after a vitrectomy that your eye feels > like someone played pinball with it. Mine went quite well. However, I was on restriction for two weeks (no lifting or bending over). Since I had already given notice at work, and had planned to spend the next week cleaning out my office, this was a problem. I talked to my boss and extended my leaving another two weeks. This was a good thing, since I had over a hundred days of sick leave, so I spent two weeks at home at full pay. My vitrectomy was done with the older 20-gauge equipment, which required sutures. One day post-op my eye was practically swollen shut and bright red. I looked terrible, although it wasn't painful. I later developed a severe suture reaction, which was reportedly related to the (mis)placement of the sutures (put in by a resident who--in my opinion--didn't know what he was doing.) This left an unsightly red mound on the white of my eye that lasted for weeks. But happily, surgery with the newer 25-gauge "sutureless" equipment inflicts no such torture on the patient. I believe the surgery time is quicker, and recovery is reported to be faster and painless. I believe that Charles has a lot to gain from the procedure and should certainly schedule a consultation with the best retinal surgeon in his area. (This does not require a referral from an optometrist.) I haven't kept up with my reading in the area of retinal surgery. However, I do know that just a few years ago a vitrectomy was not done to remove a macular pucker until vision was worse than 20/60. Today, with better equipment and technique, some surgeons will operate on a patient with 20/20 vision if the distortion from the pucker is bothersome. I also believe that vitrectomies for floaters are performed more frequently today than in the recent past. I think the chance of endophthalmitis is pretty small, given modern day procedures and antibiotics. And I think that "cracked" is a poor choice of words to use with someone who is not familiar with the procedure, where 3 very small holes are cut in the eye for the instrumentation. It is minor in that the patient is usually not under deep anesthesia, and intubation of the trachea is usually not needed. I think vitrectomies for major vitreous opacities is becoming more common, as it is quite successful. This person should indeed consult a vitreous surgeon before consulting a psychiatrist. w.stacy, o.d. > > [quoted text clipped - 38 lines] >like someone played pinball with it. > >And I think that "cracked" is a poor choice of words to use with >someone who is not familiar with the procedure, where 3 very small >holes are cut in the eye for the instrumentation. The euphemsm was used to make the point was that vitrectomy is *intraocular* surgery, like cataract surgery or refractive lensectomy, not extraocular surgery like LASIK or PRK. When an entry point into the eye is made -- even for transconjuctival sutureless 25-gauge pars plana vitrectomy (PPV) -- new sets of risks are involved. And don't even ask what would happen if a pars plana approach fails and they perform "Open Sky" vitrectomy. >I think vitrectomies for major vitreous opacities is becoming more >common, as it is quite successful. I think it is likely there is a very good reason his ECPs apparently hasn't referred him to a retinal surgeon for a vitrectomy eval after 7 years of "very bad floaters". However, if only for his mental health, I would obtain vitreo-retinal consultation for this gentleman. According to a June '06 article on emedicine.com, postoperative endophthalmitis is a rare complication of intraocular surgery. Data from Bascom Palmer from '84 to '94 show that only 0.05% of patients developed endophthalmitis after pars plana vitrectomy. (The rate was 0.08% for patients undergoing cataract extraction.) Even with the older 20-gauge equipment, having a vitrectomy is not a painful ordeal. My surgery was done at a teaching hospital with local anesthesia alone. (I opted to skip the sedation.) I experienced no pain during the surgery and was actually able to see the instruments in my eye and follow the action. (A fascinating and hopefully once-in-a-lifetime experience.) After the surgery (with one eye patched), I had lunch and then walked over to the local multiplex, where I stayed for a double feature. My vision improved from 20/50 to 20/20 during the weeks that followed. You guys really perform a valuable service for us nonprofessionals by posting info on this web site. But I really disagree with you in this case, Anon E. Muss, and your comment about antidepressant medication is a little offensive. Have some empathy--how would you feel living your life with the types of problems that Charles has been experiencing? >But I really disagree with you in this case, Anon E. Muss, and your >comment about antidepressant medication is a little offensive. The OP wrote, quote: "I have what I consider to be very bad floaters for the past 7 years" "It is also not an exaggeration to say that the globs torment me almost all of the time and seem to cause persistent eye strain and tearing" It is not unreasonable to recommend for someone who has been tormented almost all the time for the past 7 years for whatever reason to undergo a psychiatric evaluation. Even more so when the objective findings (i.e., 20/20 vision with no eye pathology) do not concur with his subjective complaints (i.e., torment). 20/20 is a subjective finding, not an objective one. And floaters notoriously cause 20/20 vision to drop to 20/100 or worse as the floater passes over the macula. w.stacy, o.d. >Even more so when the objective findings (i.e., 20/20 vision with no >eye pathology) do not concur with his subjective complaints (i.e., >torment). > I should rephrase that: "large floaters notoriously CAN cause 20/20 vision to drop to 20/100 or worse as the..." > 20/20 is a subjective finding, not an objective one. And floaters > notoriously cause 20/20 vision to drop to 20/100 or worse as the [quoted text clipped - 5 lines] >> torment). >> >20/20 is a subjective finding, not an objective one. Quick answer: In the standard SOAP format for medical records, visual acuity is recorded in the "O" section for (O)bjective. Longer answer: When a patient's visual acuity is properly tested using a wallchart with a patient who is being honest and giving proper effort, I consider that to be an objective record of his visual acuity unless proven otherwise. No, it's NOT *purely* an objective test of visual function like a visual evoked potential (VEP), optokinetic response (OKN), functional magnetic resonance imaging (MRI) or a pattern electroretinogram (pERG). Yes, people can lie, not give good effort, can be hysterical, malinger or have otherwise non-physiologic loss of visual acuity. But performed properly with a patient who is honestly trying and giving his best effort, it is, in my book, an objective test of his visual function. It should be measurable, repeatable and consistent. It's part of the art of being a doctor that allows one, generally, to determine whether to believe in the objectivity of the test results. When someone says they can read those 20/20 letters, but they are "fuzzy", "dim", "clear", etc., then that is a subjective response. In the same way, I consider a confrontation visual field that clearly demonstrates a total homonymous hemianopia to be essentially objective. And whether it is performed by confrontations, a tangent screen, kinetically via Goldmann perimeter, a Matrix FDT or automated via an Octopus 101, it's still gonna be there. The exact extent will vary from test to test and is influenced by a person's subjectivity, but an person educated in interpreting visual fields will clearly be able to see it's there each and every time. I consider extraocular motilities to be objective even though people can fake those too. Maybe this will help: I consider anything which is a "sign" to be "objective" even if it requires some sort of patient response or interpretation: Loss or presence of normal snellen visual acuity, clear cut visual field defects (e.g., homonymous hemianopia), restriction on extraocular motilities, abnormal color vision plate test result, cover/uncover test results, acquired torsional nystagmus, absence of stereoacuity, positive photostress test, exophthalmometry, clear cut "red cap desaturation test"/afferent pupillary defect. I consider anything which is a "symptom" or complaint to be "subjective": Vision is clear/blurry, can't see off to one side, can't move my eyes to the right, hard to tell difference between navy blue and purple socks, eyes cross, vision shakes, can't thread a needle, can't see for a long time after car headlights blast me at night, eyes bug out, colors/lights seem dim out of my one eye. P.S. Got a pachymeter about a month ago. :) >>20/20 is a subjective finding, not an objective one. > > Quick answer: In the standard SOAP format for medical records, visual > acuity is recorded in the "O" section for (O)bjective. Once again I disagree with the "standard" then. Acuities and *subjective* refraction data belong together in the SUBJECTIVE area. Retinoscopy and auto-refractions belong in the OBJECTIVE area. > Longer answer: When a patient's visual acuity is properly tested > using a wallchart with a patient who is being honest and giving proper > effort, I consider that to be an objective record of his visual acuity > unless proven otherwise. But you cannot determine the degree of "honest and proper effort". That's why it's so variable and subjective. > No, it's NOT *purely* an objective test of visual function like a > visual evoked potential (VEP), optokinetic response (OKN), functional > magnetic resonance imaging (MRI) or a pattern electroretinogram > (pERG). Yes, people can lie, not give good effort, can be hysterical, > malinger or have otherwise non-physiologic loss of visual acuity. Nor can you ALWAYS tell if they are hysterical or malingering. > In the same way, I consider a confrontation visual field that clearly > demonstrates a total homonymous hemianopia to be essentially [quoted text clipped - 4 lines] > but an person educated in interpreting visual fields will clearly be > able to see it's there each and every time. I also put these in the subjective realm. > I consider extraocular motilities to be objective even though people > can fake those too. Fake a strabismus? Or more important, fake orthophoria when the patient is a strab? I think not. But obviously these are objective, as we are making direct OBSERVATIONS by definition. OTOH, things like phorias and fixation disparity measurements are just as obviously subjective items. > Maybe this will help: > [quoted text clipped - 6 lines] > positive photostress test, exophthalmometry, clear cut "red cap > desaturation test"/afferent pupillary defect. Some of those are signs, some are symptoms. You're lumping them together, I think unnecessarily and confusingly. > I consider anything which is a "symptom" or complaint to be > "subjective": Vision is clear/blurry, can't see off to one side, > can't move my eyes to the right, hard to tell difference between navy > blue and purple socks, eyes cross, vision shakes, can't thread a > needle, can't see for a long time after car headlights blast me at > night, eyes bug out, colors/lights seem dim out of my one eye. Agreed with those, if reported by the patient and not observable (eyes bug out should easily be observable as exophthalmos or proptosis). > P.S. Got a pachymeter about a month ago. :) A very good objective test, don't you think? I'll bet you're using it more than you used to "order it" from your glaucoma guy? I had a nice exchange with a lecturer at the Monterey Symposium in which he asked for a show of hands as to who was "modifying goldmann readings" by the pachymeter. I was about the only one to raise my hand. He challenged me and I said I do it in my head, not on paper. Helps me get a feel of what's going on. He then explained patiently that my correction tables are not all that accurate. I patiently explained to him that in most aspects of medicine even variable or imperfect corrections are better than no corrections at all. Love to make those guys squirm. He allowed that it was a good point. w.stacy, o.d. [snip] >Once again I disagree with the "standard" then. No use debating with you about it then. >> I consider extraocular motilities to be objective even though people >> can fake those too. > >Fake a strabismus? Or more important, fake orthophoria when the patient >is a strab? Not cover/uncover test, but extraocular motilities. You know -- checking for a full range of motion with no gaze restrictions. These can be "faked". >> P.S. Got a pachymeter about a month ago. :) > >A very good objective test, don't you think? It is (however, the fundus camera we recently got is much more useful.) I always recommend measuring central corneal thickness (CCT) for all ocular hypertensive patients (i.e., <22.5mm Hg per uncorrected Goldmann applanation tonometry [GAT]) per the OHTS recommendations, glaucoma suspects (e.g., those with suspicious optic nerves, retinal nerve fiber layer defects, drance hemorrhages, strong family history, etc.) and definite glaucoma patients. >I'll bet you're using it more than you used to "order it" from your >glaucoma guy? Indeed I am. BTW, I never ordered it from a "glaucoma guy". I obtained CCT measurements, objective retinal nerve fiber layer analysis (i.e., GDx VCC or Stratus OCT), objective optic nerve analysis (i.e., HRT3) and optic nerve photographs on all my glaucoma patients/suspects from the special testing clinic at SCCO. Now that I have a pachymeter and a fundus camera, I do that in house but still turf out the imaging to SCCO. I do wish they'd get an Octopus 101 in addition to the HFAs they have there. BTW, it works out great. Future ODs (students) get exposed to glaucoma patients, patients get access to cutting edge diagnostic technology, I know I'm getting the testing I ordered done and my patients sent back to me versus always wondering with the OMD, I'm comfortable with the ODs there (for the most part) and I don't have to worry about expensive lease payments on still evolving technology. >I had a nice exchange with a lecturer at the Monterey Symposium in >which he asked for a show of hands as to who was "modifying goldmann [quoted text clipped - 5 lines] >imperfect corrections are better than no corrections at all. Love to >make those guys squirm. Too bad you weren't at the Academy this year and didn't get the chance to try and make Murray Fingeret, Harry Quigley and David Friedman squirm during their glaucoma lecture. Heh. The Ziemer Ophthalmic rep (maker of the Pascal Dynamic Contour Tonometry [PDCT]) said they've done a ton of testing comparing GAT to PDCT in conjunction with CCT. They said that when a cornea is thin, the GAT usually, but not always, reads low. However, they said that when a cornea is thick, there was no clear trend -- it could be lower, higher or unchanged versus PDCT. And hence the problem with adjusting IOPs based on CCT -- you just don't know if the adjustments you are making are accurate. Per the Ziemer rep, a patient with a GAT reading of 19 and a CCT of 595 could have just as much a chance of having a "real" IOP of 23 as 17. And the patient with a GAT reading of 17 and a CCT of 515 might have a "real" IOP of 18 or 23 -- you just don't know. Both Goldmann and these adjustment algorithms are inprecise and "noisy" and when you compensate you are IMHO losing more in "noise" than you are gaining in terms of diagnostic info. (The "21" or "22.5"mm Hg cutoff for OHTN is arbitrary too -- it's based on old data that said "21" was 2 standard deviations above the average. Those numbers don't come from any well-designed studies -- they were literally pulled out of the air.) One thing we know with a high degree of certainty is that if you are an OHTN (per uncorrected GAT readings) and have thin corneas, your risk of developing glaucoma within 5 years is considerably higher than if you have thick corneas. Another thing we know is that when one is developing progressive glaucomatous optic neuropathy, the only proven way to lower the risk of continued progression is to lower the IOP. In other words (IOW), it's not so important what a particular person's exact IOP is (within reason) as far as saying this person does or doesn't have glaucoma -- more important is if someone has unquestionably progressive glaucomatous optic neuropathy, their IOP isn't consistently low enough for their optic nerve (i.e., their optic nerve is too sick/weak to tolerate that particular IOP) and the IOP needs to be lowered. Of course, this "need" needs to be looked at in the context of the estimated rate of progression, the patient's estimated life span and the impact on the patient's qualty of life with treatment versus not treatment. There is a great article by George Spaeth et al (Surv Ophthalmol. 2006 Jul-Aug;51(4):293-315.) discussing this very issue in combination with his "Disc Damage Likelihood Scale" he helped develop (see <http://tinyurl.com/vzhyy>). It's a little complex and overwhelming for the private practitioner to implement I think, but the ideas and foundation are quite strong. In summary, I don't think by compensating for IOPs that you are obtaining more valuable diagnostic data than I do when I measure CCTs and merely label those OHTN patients with thin corneas and having an additional risk factor and those with thick corneas as having a protective risk factor. And that goes along with the general consensus of glaucoma experts. Far better IMHO to go on what the OHTS study said -- thin CCTs are a strong predictory risk factor in OHTN patients that developed glaucoma (see <http://tinyurl.com/vlc22>). Deja vu. I think we've discussed this before. > In summary, I don't think by compensating for IOPs that you are > obtaining more valuable diagnostic data than I do when I measure CCTs [quoted text clipped - 8 lines] > > Deja vu. I think we've discussed this before. Indeed. But thanks for taking the time to so concisely present the issue. This is precisely what the glaucoma specialists in my neighborhood live by and that which most of us have come to accept as valid rationale for the diagnosis and management. At least for now. But on another, possibly related issue: What of the thousands of LASIK's/PRK'd people with now thin corneas? Might they have to classified as higher risk glaucoma suspects? Do thin corneas alone predict risk or is there an underlying genetic cause that relates simultaneously to thin cornea and glaucoma? Inquiring minds........ LB, O.D. (rarely seen around these parts these days) >But on another, possibly related issue: >What of the thousands of LASIK's/PRK'd people with now thin corneas? >Might they have to classified as higher risk glaucoma suspects? Not at this time -- there is absolutely no evidence that I am aware of that iatrogenically thinned corneas (ITC) increase the risk of developing glaucoma any more than performing full-thickness penetrating keratoplasty with a "thick" donor graft would be "glaucomaprotective". The important thing to realize is that the applanation/indention tonometry readings you get on ITC will almost certainly be more inaccurate than ever. And all the "conversion tables" used as far as I know are based on natural corneal thicknesses, not iatrogenically altered ones. Therefore, you really have no idea how much your readings are off here. I believe it is very fair to assume that your Goldmann applanation readings (GAT) will be falsely low. How low? It's not real clear. So what do I do in situations like this? [Well, it's like patients I have with tilted discs; in those patients, I rely a lot more on looking at the fields, the optic nerve (ONH)/retinal nerve fiber layer (RNFL) imaging and the IOP. Or it's like the patients I have that are horrible at taking visual fields; in those patients, I put more weight on the ONH/RNFL imaging, the optic nerve appearance, the retinal nerve fiber layer and the IOP.] I really pay more attention to the perimetry results, the imaging results and the fundus appearance -- realizing that the IOP reading is not going to be all that accurate, but reasonably assured it will be precise (see <http://tinyurl.com/y4yglp> under the section "Accuracy vs precision - the target analogy"). The Ziemer ophthalmic guys say their Pascal Dynamic Contour Tonometer (PDCT) is great for situations like this -- actually, they say it's great for everybody and accurate/precise -- but at around $4K a pop I'm still waiting. I've talked to some people who are commonly considered to be glaucoma experts in the Optometric community and their opinions are mixed -- some thing it's useful, others told me they aren't so sure it's precise. What the PDCT guys need to remember is that our treatment of glaucoma is based on many years where GAT was (and still is) the "gold standard" for IOP measurement. And what we should realize is, and I wrote about this earlier in the thread, knowing the exact IOP may not be all that crucial in the vast majority of glaucoma cases. What we really need is a test that is *precise* (i.e., "off" consistently by the same amount) from visit to visit, because one of our barometers in glaucoma treatment is IOP lowering. In other words (IOW), when we measure IOP, it may not be as important to know whether the IOP really was "23" before treatment and now it is really "17", rather what is important is that the knowledge that we *really have* lowered the IOP by ~25% is reliable. We believe the GAT is precise (enough). I write this in light of the fact the many people with ocular hypertension (OHTN) never develop glaucoma and the many people with IOPs never measured <22mm Hg that develop glaucoma. Precision may be a lot more important than accuracy, though in a perfect world, we want a device that is both. >Do thin corneas alone predict risk or is there an underlying genetic >cause that relates simultaneously to thin cornea and glaucoma? The general consensus of glaucoma experts I have spoken to and read articles from believe that central corneal thickness (CCT) is an indirect measurement of something else that is the real risk factor. Interesting tidbit: I didn't know this until the 12/2006 Academy meeting, but Harry Quigley informed the audience that CCT even being measured in the Ocular Hypertension Treatment Study (OHTS) was only in there because one ophthalmologist (OMD) at UC Davis (I don't think he mentioned this doctor by name, but I believe it is James Brandt) strongly wanted it in there. Interestingly, this same OMD -- the one that lobbied to have CCT measured in the OHTS -- argues *against* adjusting IOPs based on CCT readings in the 12/01/2006 issue of "Ocular Surgery News" (see <http://tinyurl.com/y7sq42>) and gives his rationale for such recommendation -- important quotes: Pachymetry over the past few years has come of age with the recognition that corneal thickness is a very big issue in the accuracy of measuring IOP and the assessment of risk in our glaucoma patients, Dr. Brandt said. If you have a patient with a thin cornea and higher pressures, that individual is at much higher risk of developing glaucoma than somebody with the same IOP but a thicker cornea. and Because of the inherent error in Goldmann measurement, he suggested, it is of questionable value to adjust a patients Goldmann IOP by using a nomogram based on corneal thickness. You are kidding yourself if you try to apply an algorithm to adjust by a few millimeters of mercury the underlying measurement, which is imprecise, Dr. Brandt said. Bs pbhefr, guvf jba'g pbaivapr Ovyy Fgnpl :) P.S. To be fair, there are some that do advocate IOP adjustment based on CCT such as Leon Herndon in a recent article in "Ophthalmology Times" (see <http://tinyurl.com/szjy2>), but they are definitely in the minority. However, in this same article in Ophthalmology Times James Brandt again counters with a far more (IMHO) compelling argument. [snip] >Interestingly, this same OMD -- the one that lobbied to have CCT >measured in the OHTS -- argues *against* adjusting IOPs based on CCT >readings in the 12/01/2006 issue of "Ocular Surgery News" (see ><http://tinyurl.com/y7sq42>) and gives his rationale for such >recommendation -- important quotes: [snip] > You are kidding yourself if you try to apply an algorithm to > adjust by a few millimeters of mercury the underlying > measurement, which is imprecise, Dr. Brandt said. I believe he meant "inaccurate". :) > I write this in light of the fact the many people with ocular > hypertension (OHTN) never develop glaucoma and the many people with > IOPs never measured <22mm Hg that develop glaucoma. Given the context of your post, I think you meant never measured >22. w.stacy, o.d. >> I write this in light of the fact the many people with ocular >> hypertension (OHTN) never develop glaucoma and the many people with >> IOPs never measured <22mm Hg that develop glaucoma. > >Given the context of your post, I think you meant never measured >22. How's this? A lot of people with consistently "high" IOP never develop glaucoma and a lot of people with consistently "low" IOP do develop glaucoma. As a result, IOP measurement is a very poor method of screening glaucoma patients from normals in the vast majority of the population. >>>I write this in light of the fact the many people with ocular >>>hypertension (OHTN) never develop glaucoma and the many people with [quoted text clipped - 9 lines] > As a result, IOP measurement is a very poor method of screening > glaucoma patients from normals in the vast majority of the population. Agreed, it's just that your quote translates: "many people with iops never measured "LESS THAN 22mm Hg develop glaucoma." That statement is certainly true, although it would be more meaningful to have said "most people who never measured less than 22mm Hg have glaucoma". But what I think you were trying to say was what I originally answered above. It's kind of a pet peeve of mine, like when people specify + when they meant - in an Rx. Or when the order says "DNR" when the patient is not terminal. Little things like that sometimes are important. w.stacy, o.d. |
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