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Ophthalmology - Science topic

Eye Disease Management and Oculoplasty
Questions related to Ophthalmology
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I am currently attempting dissection of the mouse aorta to expose the endothelium for Oil Red O and other standard stains. I am using ophthalmological scissors to open the vessel from the outer curvature and I pin the vessel along the inner curvature to secure it.
However, I find myself slipping out and 'getting lost' in the vessel, and I cut several times as I try to find my way back in. Sometimes it seems ambiguous whether I actually entered the vessel or not. As a result, my final tissue preparations have edges that are not clean and defined. I am also struggling with pinning straight, with some orientations of the prepared aorta seeming ambiguous.
I am looking for any technical tips on how to make my cuts more defined and clean so that the final endothelial presentation looks good enough for a publishable figure. Does anyone have any advice on this?
I attach pictures of vessels I have attempted, as well as a link to a quality of preparation in a figure style that I would ideally like to replicate!
Thank you so much for looking this over and for helping me out.
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Hi.
I don't know, which scissors dou you use. I would recommend a Castroviejo micro scissor. They must be very sharp. If you cut the aorta after explantation it's more difficult, and you can try to fill the lumen with saline solution/medium/buffer, if it doesn't interfere with your experiments. In the case that you open the aorta before explantation, it should be easier.
I presume you use a microscope
Best regards
AO
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I have ophthalmology resident trainees who want to perform a systematic review and/or meta-analysis in glaucoma and want opinion from other experts about what topic seems relevant for them in this specific field
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Prolonged uses of antiglaucoma and its ocular surface side effect.
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Currently, the powder form of pilocarpine nitrate is not available in chemical companies in my country..So can i use commercially available pilocarpine nitrate eye drops for intraperitoneal injection in rats (used once to stimulate salivary flow at the time of sacrifice) ?
Thanks in advance.
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What is the submission to publication period of the middle east african journal of ophthalmology?
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The literature is conflicting with approximately half of the studies reporting no change in colour vision and the remainder a change. The interesting group of patients are those with a tinted implant in one eye and a plain one in the fellow eye. There is a case report of one such patient demanding the tinted implant to be explanted
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I am answering this as a patient as I have no medical qualifications whatsoever, thus it's an experiential report. I recently acquired a clear implant, vs the other one, implanted two years ago, which was yellowish. I believe both have a UV filter, but the tinting is different: that can clearly be seen by shutting each eye in quick succession and comparing. When both eyes are used, I see something in between: the difference does not bother me in terms of everyday vision, but I do prefer the yellow tint (warmer) in terms of perception. I am very happy with the results so far, but had I been given a choice of 'coloring' I would probably have chosen tinted in both eyes, provided there were no medical disadvantages. I also prefer warm lights in general (say inside the home etc.), but I know people who prefer cold lights - perhaps they would prefer non-tinted implants. Still- having both 'options' is also interesting: each eye sees differently, and sometimes better, more detail etc., compared to the other, in differing light conditions, so that could be regarded as an advantage I suppose, a kind of (slightly) improved potency.
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I have performed a survey of ophthalmologists' attitudes towards vaccinations for patients with corneal transplants and the controversial and weak association with rejection. In trying to write up the paper, I am struck at the lack of evidence for these concerns in the ophthalmology literature (4 historic case series/papers, and 2 contradicting larger studies). Can any ophthalmologists, immunologists or solid organ transplant teams comment from their knowledge of their literature within their field? Is there an agreed scientific basis and mechanism for these concerns (even if theoretical)?
Thanks!
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Dear colleague, at the moment we have few described cases... I suggest the last article of our group @pietronapoli
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A young female patient was diagnosed to have cone dystrophy and she wants to know if there is any cure including gene therapy or even anything that can stop progression
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Sorry, but I never heard about it.
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I am a graduate student in ophthalmology and I am currently hoping to write a review or meta-analysis in diabetic retinopathy or high myopia, and I would like to ask research experts in the related field what they would recommend.
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Yes, what are the microenvironmental conditions of the retina and vitreous that protect high myopes from developing diabetic retinopathy? Mexico has the highest prevalence of DM-II; we are overwhelmed by patients suffering from PDR buy patients with moderate and high myopia with no intraocular surgery do not show the retinal disease.
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The behavior of bacterial/fungal keratitis do not not allow the doctor to wait for laboratory support to start treatment as every moment is crucial in saving the cornea. After having sent the swabs for identification of infecting organism and culture/sensitivity reports, the best option seems in following "Imtiaz's law of inversely proportional hypopyon" which states that in fungal keratitis, hypopyon is less than the size of ulcer in contrast to bacterial ulcer where hypopyon is usually more in size than the ulcer area relatively. Therefore immediately embarking on treatment on the basis of this law seems justified.
Ref: Shah SIA et al: Concise Ophthalmology Text & Atals. 5th ed. Param B (Pvt.) Ltd. 2018: 48-49
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Dear Alejandro Rodriguez-Garcia, your recommendation clearly indicates that you are a transparent researcher with a deep sense of sympathy for humanity and not a researcher like robot who do not have a logical sense of elasticity in assessment and do not possess innate innovative capability. Hats off.
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Delhi, Tamil Nadu, and Kerala Ophthalmological societies have their own journals which are unfortunately not indexed in pubmed? What's your take on publishing works in these journals as first choice?
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Respected sir,
Indian journals like TNOA, KJO, JCOR,etc are indexed in directory of open access journals (DOAJ). According to recent NMC guidelines articles published in DOAJ indexed journals will be considered for academic promotions. Even case series published in these journals will be considered. So if somebody has academic promotion as the primary aim for publishing, then he/she can consider publishing in these journals.The quality of these journals are quite good.
But on the flip side, as has been previously answered, these articles will not get wide peer attention since they are non pub Med indexed.
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This occasionally occurs following IntraLase  but how do colleagues manage the patient and is the outcome affected ?
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Do not lift flap. Apply 5% betadine, topical anesthetic and bandage conact lens. Have patient sit upright until bubbles dissipate. Small bubbles are hard to see at slit lamp. You can periodically have patient lay of table to bring the bubbles to the apex. You dont have to redrape. You can also test iris reistration with BCL in place simply by parting lids with fingers without full lash drape and speculum.
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I'm part of a team designing an observational study in which we're going to compare 2 models of intraocular lenses. The main outcome is contrast sensitivity.
I'm having some difficulty in understanding how we are going to handle this variable in statistical analysis and looking at the literature hasn't helped me much. It's also important because, being the main outcome, our sample size calculation depends on that.
Has anyone worked with something similar and can give me some pointers?
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Hi,
From the available literature get the stats of comparison between the two IOLs. Stats on the various measures of Contrast sensitivity and factors influencing them. Get hold of the comparative tests, Std. Dev, Std error, Confidence intervals. find out whether any Ethnic or other factors are important in the study. If your study is mostly similar to those studies, Put those values from the literature onto the Sample size calculation formulae and calculate the number for each group for a given level of significance and power. Then plan and execute the study.
Alternatively, as a part of the pilot project get the numbers and calculate the sample size.
There is sample size calculation software available on Google that you can use.
Here are some references on the topic under discussion:
Crnej A, Buehl W, Greslechner R, Hirnschall N, Findl O. Effect of an aspheric intraocular lens on the ocular wave-front adjusted for pupil size and capsulorhexis size. Acta Ophthalmol. 2014 Aug;92(5):e353-7. doi: 10.1111/aos.12344.
Ferrer-Blasco T, García-Lázaro S, Belda-Salmerón L, Albarrán-Diego C, Montés-Micó R. Intra-eye visual function comparison with and without a central hole contact lens-based system: potential applications to ICL design. J Refract Surg. 2013 Oct;29(10):702-7. doi: 10.3928/1081597X-20130919-03.
Hida WT, Motta AF, Kara-José Júnior N, Costa H, Tokunaga C, Cordeiro LN, Gemperli D, Nakano CT. Estudo comparativo do desempenho visual e análise de frente de onda entre as lentes intra-oculares multifocais difrativas Tecnis ZM900 e AcrySof ResTor SN60D3 [Comparison between OPD-Scan results and visual outcomes of Tecnis ZM900 and Restor SN60D3 diffractive multifocal intraocular lenses]. Arq Bras Oftalmol. 2008 Nov-Dec;71(6):788-92. Portuguese. doi: 10.1590/s0004-27492008000600004.
Avitabile T, Marano F. Multifocal intra-ocular lenses. Curr Opin Ophthalmol. 2001 Feb;12(1):12-16. doi: 10.1097/00055735-200102000-00004
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With the ever increasing potential of using Big Data in Healthcare in India, this discussion is aimed at sharing your experiences and challenges in publishing from large clinical datasets in Medicine.
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Lisbeth Bang Thank you for your comment. We have progressed far beyond in domains like finance and social media when it comes to handling voluminous loads of data. In healthcare however we are now realizing the potential of mining large datasets generated over the years. We will learn a lot for sure as we explore this path for generating insights to help increase the efficiency of health care delivery in different geographies. As
George Stoica
mentioned, we are getting better and better at mining information and this will become the NEW NORMAL for us healthcare practitioners.
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Dear All
Can you please suggest me a few journals related to
Machine learning application for Ophthalmology
Thanks.
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As a researcher, you may be frustrated in finding continuous funding for sustaining your research. However, would there be any conflict of interest to be a researcher as well as a fund raiser simultaneously at the same time?
What regulations are there to limit the grey area?
Which authorities were looking on such issue?
What if the fund raising is for charity organizations in the field (particularly pediatrics and rare diseases) and is unrelated to the researcher's work?
In medicine field, the practice of physicians fundraising from their own patients raises three main concerns:
(1) undue pressure on patients to contribute,
(2) possible expectations of preferential treatment from donors, and
(3) concerns about patient confidentiality and trust.
What do you think?
https://doi.org/10.13140/RG.2.2.26948.24966
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This largely depends on the system of financing science in a given country and the policy of financing research in specific types of universities. It is not a comfortable solution for researchers and scientists to independently search for sources of funding for their research. Systems of granting grants and subsidies for specific research projects should be developed and improved, taking into account the potential effects of the results of these studies on solving specific problems of the development of civilization.
Best wishes,
Dariusz Prokopowicz
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In an ophthalmology research involving endothelial examination by specular microscopy, there is a lack of correlation between the endothelial cell count and cell density, as is shown in the figure.
The results of specular microscopy examination on the 3rd month post-op shows that the mean endothelial cell count of the "red" group is lower than the "black" group, while at the same time the cell density of the "red" group is higher than the black group.
I expect that the inherent correlation between "count" and "density" would mean that one group would rank higher or lower regarding both variables; but I'm thinking that I might be wrong.
I am not an expert in specular microscopy, so I would appreciate it if someone could tell me if the data presented in this study can't be right and is impossible or is there a scientific explanation for this lack of correlation?
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Thank you James Leigh for your answer. In this case, if the area scanned is not the same in all patients of both groups, then the results of cell count are statistically meaningless. Thank you for your time and input.
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I am a medical intern, I am asking the experts to suggest topics in ophthalmology ( cross-sectional ) that can be conducted through an online questionnaire in a specific region, for the general population.
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Dry eye diseases
Cover Page LOVE YOUR EYES
Sample questionnaire in my team's current study can be found at
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With increasing COVID-19 infected cases worldwide, people around the world are practicing strict personal hygiene against infection. Alcohol-based hand sanitizer was one of the best sellers, but will it cause eye injury?
What if it is accidentally split into the eyes?
Will prolonged exposure to the evaporated alcohol cause eye problems?
Have you even encountered such an injury in your life or medical practice?
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If it irritates the eyes then I think it is harmful. It might be better to wear a face shield instead.
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Whether SCI-expanded or not.
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Details about good Ophthalmology journals publishing good work without the financial burden for a young resident in a peripheral centre.
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It depends on what you wish to publish.
For original articles you can try to publish in the concerned subspeciality:
Cornea and Anterior segment: JCRS, Cornea, BJO, Acta Ophthalmologica
Retina: Retina, Ophthalmology Retina, etc
Oculoplasty: OPRS, Orbit, PRS, etc
Glaucoma: Journal of Glaucoma, etc
Strabismus: JAAPOS,etc
Many journals accept all types of original articles: British journal of opthalmology, Indian Journal of Ophthalmology, JAMA, Canadian journal of ophthalmology, Middle east journal of opthalmology, Oman journal of Ophthalmology, etc. However, acceptance rate varies.
For case reports, photoessays and images different journals have different scopes and processing charges.
You can try publishing images in Ophthalmology images perspective, OPRS images in, BMJ case reports, IJO case reports.
There are other good quality journals pertaining to different state ophthalmological societies, which publish case reports, photoessays and studies, but most are not indexed in pubmed like: Delhi journal of Ophthalmology, JCOR, TNOA.
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I'm seeking researchers (basic and clinical ) with interest/experience in eye /ophthalmology to submit articles for a special issue. The issue will be in a major, international, Swiss based and PUBMED listed journal). Tentative title : Stem Cell Research in Eye and Ophthalmology- Current Advances and Future Directions.
Any authors considering publication of their work shortly, please contact me IMMEDIATELY to express your interest.
Thank you!
Steven Levy MD
Study Director: Stem Cell Ophthalmology Treatment Study 1 and 2.
(001) 203-423-9494
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I am interested
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I am writing a thesis on it so
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With a knife 2.65 mm!
As usual I use for toric calculators (like Barrett) values - 0.15-0.16 for OD and 0.21-0.22 D for OS like an average values for all types of incicions! Result are quite good!
For Holladay toric calculator I use some bigger values!
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I've just read research which was done in Pakistan where the researcher had achieved very good result (97%) by full time patching in patients between 13 and 35 years old. Let me know your experience or share any research in this regard. 
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Amblyopia treatment has been successful in patients of any age group. Clinical evidence and researches regarding this query suggest that it is possible to improve visual functions in cases of adult amblyopia as well. We have some cases of adult amblyopia with final improvement in visual functions after appropriate refractive correction and combined occlusion and vision therapy. Presence of plasticity in visual system/visual cortex counter the limitation of adult amblyopia treatment. Strabismics have shown some difficulty.
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If the coronavirus is able to enter the body through the eye through its receptors on the conjunctiva, what visual problems can it cause?
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Apart from conjuntivitis, retinal findings in patients with COVID-19 have shown hyper-reflective lesions at the level of ganglion cell and inner plexiform layer, with subtle cotton wool spots and microhaemorrhages along the retinal arcade among few cases in a study conducted by Paula M Marinho and team, attributing this findings to CNS manifestation of COVID-19
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What is the role of atropine here?
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No indication for an ocular surface condition like phlyctenular keratoconjunctivitis, which is a type-IV (cell-mediated) hypersensitivity reaction to high-MW bacterial (Staph, mycobacteria) capsule proteins. Phyctenular ulceration may occur, but it usually involves the gelatinous proliferative tissue on its apical portion, rather than the corneal epithelium. On the other hand, AC inflammatory reaction is not a common feature of the disease; therefore, ciliary spasm is not frequently present.
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1. Can academic trial be conducted on platelet rich plasma in india? 2. Is there aby permission required from specific do  conduct research on prp? 3. Are there spring guidelines on who and where prp can be prepared? For example if a dermatologist want to do research on prp, can he prepare it in his department? 4. who can prepare prp? is a MD student from dermatology or Opthalmology or any specialty can learn how to  prp preparation from transfusion medicine and prepare it? Or it can be prepared only by a professional from transfusion medicine? 5. What are the approved indications for use of prp? 6. Are there any specific guidelines for method of preparation of prp? 7. Are they any specifications for the site where prp can be prepared? I will be highly thankful if the aforementioned queries are addressed by you.
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Liked your answer for PRP PrProduct rich placebo
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How should we adjust under COVID-19? Avoid non-urgent surgery?
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Any body suffering from any infectious disease must not go for surgery including eye.
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I need the list of Predatory journals in ophthalmology...Thanks
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Dear experts, have a look at this thread about PREDATORY JOURNALS and share your experience. https://www.researchgate.net/post/Are_you_serving_predatory_journals_as_a_peer-reviewer_or_editor
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Do you know the name of such referencing style? Any software suggestions for that? I have been asked to do that when submitting manuscript to survey of ophthalmology. This is Weird
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Hi Mohammad,
The Council of Science Editors (CSE) citation style handles this issue, but not sure if this style is available within Mendeley. I used paperpile citation software and it worked perfectly.
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I would like the article:
Bilateral idiopathic cystoid macular edema: Report of four cases---Tabatatbaee SA, Soleimani M, Rajabi MT, Kiarudi MY.
International Journal of Ophthalmology 8(11): 2182-2184 November 2008
Can you please send it to wendy.isser@va.gov
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hello you can go https://sci-hub.se/ by VPN
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There are very few case reports of ATONIC PUPIL after uneventful cataract surgery and that too in old literature.
With ATONIC Pupil I mean, FIXED DILATED (~8mm or more) PUPIL without any damage to iris structure.
In your journey in Ophthalmology, If you have faced any such situation, please share your experience and how did you manage that case.?
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The causes could be:-
1. Sphicter tear
2. Atonic pupil.
3. Iatrogenic - some staff had used atropine eye drops by mistake.
4. Raised IOP due to unwashed viscoelastic.
5. Neurological cause -a missed internal ophthalmoplegia
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I am trying to understand how the depth information in SD-OCT A-scans is obtained over distances far in excess of the source coherence length.
From what I have gathered so far, it seems that the fringe frequencies within the spectrally resolved interferograms encode depth information, and that this frequency is proportional to path length difference. What I really don't understand is why, and how this information is so precise as to be allocated a specific pixel depth.
Underlying this question is also that of the importance of source bandwidth. I *think* understand the notion of coherence envelopes, and it makes sense to me that path differences corresponding to integer multiplications of the coherence length give rise to new intensity minima and maxima, ergo the axial resolution of the system. But I had considered coherence length to be an intrinsic property of the source, and yet, the spectrum must be spatially (SD-OCT) or temporally (SS-OCT) resolved into narrowband components before Fourier analysis. Am I right to assume then, that wavelength dependant information is aggregated either before or after the FFT? If so, or even if not, how does backscattered light interfere more frequently with the reference arm? (I believe that I have been misled by the false premise that light will interfere if and only if its is superposed with its identical twin "packet", where it diverged at the coupler?)
I have inspected the Fourier transform equations of intensity as a function of spectral band width and indeed, time delay (correlating to depth) is encoded. What I fail to understand is not the maths, per se, but the intuitive behaviour of the light that gives rise to these equations. A lot of the literature evaluates the maths but so far, I do not have an intuitive, or qualitative understanding of the physical waveforms interfering with the reference beam from different depths and how this translates to predictable variations in fringe pattern.
This short paper: Measurement of optical distances by optical spectrum modulation from A. F. Fercher et al. , in part describes more elegantly my clumbsy question above, but proceeds to answer the question (page two onwards) with maths that I haven't been able to interpret.
My background is biomedical, so perhaps the notation and syntax of the predominantly mathematical descriptions are a barrier to this.
Frustratingly, TD-OCT is relatively a lot simpler, and I've been able to decipher that without much ado.
Thank you in advance - I apologise for the lengthy question.
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Let me try.
If you understand TD-OCT, it is great. So you understand that the wider the bandwidth of the light source, the shorter the coherence length (higher resolution of OCT image). That means if you use infinity bandwidth, you will have infinitely short coherence length and the signal would be only exactly at dz=0 (d_obj = d_ref). So now, let consider in other way. Start limit your bandwidth. You shall find that signal oscillation does not disappear so rapidly as before, so there is some vicinity of positions around dz=0 at which you still can see the signal. If you reduce bandwidth more and more up to exactly single wavelength you find that no matter how far you are from condition dz=0, there is always high signal (it varies as cosine signal due to interference of ref and obj light while moving the ref mirror). Ok then, so let detect this single wavelength signal by using a spectrometer in SD-OCT. What you will see is a single pixel which amplitude varies as cosine while moving reference mirror. Nothing special. So let's include a second wavelength in your light source so now you have a two-wavelength laser. Let the second wavelength differ not so much. Consider SD-OCT with a spectrometer having field of view of 100nm and having 2048 pixels operating at 1050nm center wavelength. So the second wavelength would be 1000nm + 100nm/2048 = 1000,05nm. How the signal will look like? Signal at first pixel still follows cosine cos[k(1000nm)*dz(t)]. The signal at the second pixel also shows a cosine according to cos[k(1000,05nm)*dz(t)]. As you see the phase (argument of cosine) would be slightly different. Assume dz=1mm then phase of the first pixel k1*dz=6283.2 and the second pixel k2*dz=6282.9, so it differs by 0.3 rad (17 deg), correct? You can check that at the 2048th pixel (1100nm) the phase is 5712. Now just calculate phase and cosine(phase) for each of 2048 pixel in excel and make a graph. You will see nice cosine fringe spanning along the pixels - this is your virtual spectrometer. Now put very small dz like 10um. You would see a fringe pattern which has just a single period along all pixels. At dz=0 all phases are zero and cosine(0)=1 for all wavelengths. That means in SD-OCT you see no signal! This is curious because in TD-OCT you observe maximal signal at exactly dz=0, right? Yes. Because in TD-OCT you observe a sum of all electric fields of all wavelengths by using a single photodiode. That means peaks and valleys of electric fields must match each other to produce highest interference signal. Since the peaks and valleys of electric field of all wavelenghts match perfectly (are highly coherent), they produce highest interference signal exactly at dz=0.
For dz > 0 phases of all wavelengths differs too much and corresponding electric fields rapidly loose the coherence, so the sum of them quickly decay to ~zero. As you saw in above virtual spectrometer considerations, at dz=1mm a two very close wavelengths (1000 and 1000.05) differs already by 17 deg. That means a wavelength in 10th pixel is at phase 170deg vs 1st pixel, at 20th pixel it is ~360deg. So you have one oscillation at 20 pixels, ~100 oscillations at 2048 pixels. At spectrometer you still observe nice interference fringes. But if you sum all of them (to simulate signal at TD-OCT - this is how TD-OCT observe signal) you will find that signal is zero! Sum of cosine signal along 100 oscillations would always give ~0 value. But if you observe a signal at spectrometer which has less than one oscillation, sum of it is > 0 and is highest when all pixels have 1.0 :). This is the all magic of TD and SD OCT :).
One digression. In TD-OCT if you don't move the ref mirror, signal from a photodiode is constant in time because neither k nor dz don't depend on time. To observe a signal you need to make k(t) or dz(t). In TD-OCT you can only make dz(t) by moving ref mirror so the signal at photodiode start changing oscillating with cost(k*dz(t)). Please note that you may also make k(t) - this is Swept-Source OCT where the wavelength of the swept laser is changing over the time. In SS-OCT you also use a single photodiode but you don't observe all wavelengths at once anymore like in TD-OCT. So SS-OCT is just "time-spectrometer" OCT :). I hope you will have better understanding now.
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The neurologic examination is a powerful tool for urgent bedside assessment of ICU patients with neurologic or neurosurgical illnesses. Assessing cranial nerve function is one of the most vital components In this context. Testing the pupillary light reflex evaluates the status of the second and third cranial nerves. Automated pupillometers have been developed that provide objective measures of size of the pupil and the responsiveness of the pupil to light (neuropupillary index). Although few studies reveal diagnostic and prognostic usefulness in critically ill patients, none of the studies correct/adjust for interfer and confounding effects by for example sympathomimetic or parasympathomimetic drug effects, interference from ambient light, previous cataract operation, etc.
Isn‘t it much too early to reliably use automated pupillometry for diagnosis and prognosis in daily clinical practice in ICUs?
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The size of the pupil, and the responsiveness to light is definitely a key procedure in neurological ICU patients (especially concerning intracranial pressure) as many of the other neurological tests require active participation of the patient. However automated pupillometry has not found the way to our ICU and I think that the amount and quality of studies is not sufficient yet. In my opinion, it's a great approach, as manual pupillary examination shows a great variety between the investigators. On the other hand, many critical ill neurological patients have a external ventricular drainage anyway. So I think more and larger studies are needed, if they show positive results, automated pupillometry could assist the examination in future.
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ophthalmology related to eye
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Most of the peer reviewed journals are free of cost for publication but due to high standards of the robust methodology, clear illustration with relevant graphs and plots and presentation , it is very unlikely to be published in above mentioned journals in first attempt. For novice research journal like
"Optometry and Vision Performance " can be a good option. If the article is related to community eye health and "Community Eye Health" published by London School of Hygiene and Tropical Medicine can be a good option.
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Vernal keratoconjunctivitis (VKC) is erroneously called as spring catarrh as it occurs in hot months and the better term should be a summer catarrh.
Ref: Shah SIA et al: Concise Ophthalmology Text & Atals. 5th ed. Param B (Pvt.) Ltd. 2018: 36-37
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So far, I think it is called "Spring Catarrh" because on the onset of the disease with the outbreak of the fresh pollen in the spring causing the start of the allergy which is further aggravated during summer and becomes more symptomatic.
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Which device would you use as a gold standard for verification of the project relate real keratometry of the eye. I want to verify the anterior, posterior and the real power, Sim K of the posterior, anterior and true values.
I was thinking about Casia 2000 SS-OCT from Tomey but they do not have FDA. So, what would be the best reference for the prototype software: maybe Pentacam or GALILEI from Ziemer.
Kind regards,
Bart
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If the gold standard assumes a device that is the most prevalent and the one that we can compare the other topographers with, then it is definitely Pentacam, although many other units may be better in one way or another. As mentioned earlier, the future lies in OCT technology, the fanciest of all currently being Anterion by Heidelberg.
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In simple and convenient terms, which terpenes improve vision? Are there terpenes, when inhaled, that can affect visual perception? Can they improve our ability to detect or process illusions? Can terpenes change our perception of color intensity? Do terepenes affect any enzymes associated with the functions of the eye?
The most interesting thing found so far was in a history book; Van Gogh also had some digestive problems, for which he may have taken santonin, a terpene, used at the time to treat and prevent intestinal parasites and known to cause yellow vision. This may have impacted his work.
It has been difficult to find much research related to terpenes and ophthalmology, eye health, or visual perception. I am interested particularly in terpenes found in cannabis and that are also abundant in nature.
I would appreciate any information about various terpenes such as pinene, linalool, myrcene, beta-caryophyllene, etc.
I have found some essential oil safety data, that some increase the number of eye blinks because they are irritants. additionally, any data about CBD and its effects on IOP would be appreciated.
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In one study, on animals with primary glaucoma, we are evaluating whether an ocular beta-cariophyllene eye droplet solution is able to lower the IOP for several hours. The study is underway
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Recurrent chalazia are seen to harbor adenocarcinoma clinically and on histopathology examination 1.
1. Ref: Shah SIA et al: Concise Ophthalmology Text & Atals. 5th ed. Param B (Pvt.) Ltd. 2018: 27-31
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A very good question. Recurrent chalazion is a risk. However patients under immunotherapy ,recurrent ulcerative blepharitis and with other malignancy or known to harbour the risk should be kept a close eye on. And another practice that should be commissioned is -Every piece of tissue excised from the body mandates a histopathology with proper technique of biopsy.
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Retinal Specialists keep on focusing their attention on Rhegmatogenous, tractional and exudative retinal detachments and never even like to listen about solid retinal detachment so much so that one of my colleague who is a wonderful retinal specialist was almost annoyed to see inclusion of solid retinal detachment among various types of retinal detachments in my book1.
1. Ref: Shah SIA et al: Concise Ophthalmology Text & Atals. 5th ed. Param B (Pvt.) Ltd. 2018: 85-95
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Solid retinal detachment as you very correctly pointed out..are mainly due to malignant primary ocular or metastatic tumors. But it does give a chance and patient a hope for diagnosis and possibly early treatment of the condition. Sometimes masquerades could be life saving in my opinion. I think more than disliked...it is more feared...
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History
Examination
Clinical Tests
Differential Diagnosis
Provisional Diagnosis
Investigations
Provisional Treatment
Result of Investigations
Final Diagnosis
Final Treatment
Follow up
Prognosis
Research Oriented Aspects
Ref: Shah SIA et al: Concise Ophthalmology Text & Atals. 5th ed. Param B (Pvt.) Ltd. 2018: 11.
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During teaching and training medical students, when they are asked about scheduling the clinical steps, I have always heard them saying "investigations" after history and examination, which is grossly wrong. Therefore the illustrated arrangement of clinical steps is acceptable and particularly good for trainee medical students.
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I know the OCT Spectralis is having Blue Peak, Multicolor, autofluorescence and you can add ICG and Fluorescein AGF to the platform.
With the OPtovue, you do SD-OCT and OCT-A. that is all.
Comparing just the SD-OCT and OCT-A between these devices, which one is better for you,
Thank you in advance.
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The only device that is fully multimodal is the Topcon DRI Triton, as that has an integrated fundus camera in addition to the OCT, OCTA, FAF and FA functionality. The Spectralis Multicolor is NOT analogous to a color fundus image since the image is an SLO generated by three single wavelength lasers.
That said, multimodal is not always the best choice in a busy clinical environment. In those instances, its often easier to have a couple of multimodal devices, but single devices for high volume testing. You don't want your only OCT taken up because you need to perform OCTA, or your FAF device taken up because its the only device you can do fluorescein on.
Some statistics on testing (and wait times) will help tell you what would give you the best throughput for your money. Many practices will have a few standalone devices (not multimodal) for those most popular tests, like OCT. However, standalone devices tend not to be as easily upgraded, as muiltimodal packages have more ability to be adapted to newer technology implementation (given they have everything but the kitchen sink already on board).
Image quality on all of these devices is excellent, but pay close attention to the layer segmentation of the OCT (which informs the en-face segmentation in OCTA). The interface of what "slabs" are automatically generated, should be considered too, for ease of use.
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Genetics seems to have generated immense knowledge about various eye diseases. These findings include gene mutations, their effects, pattern of inheritancel etc. So, Is this the time to have ophthalmic genetics units in every ophthalmology set up? If yes, what would be its profile and how would it support the set up?
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Well Said Dr. Angelova.
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Minimum rim width has been adapted by recent OCT devices since it takes more into account variability of the entry of the RNFL axons into the optic nerve canal
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The BMO MRW concept was first shown to have the best diagnostic performance to differentiate glaucomatous from non glaucomatous eyes on the Spectalis platform by Reis ASC, O’Leary N, Yang H, et al. Influence of Clinically Invisible, but Optical Coherence Tomography Detected, Optic Disc Margin Anatomy on Neuroretinal Rim Evaluation. Investigative Ophthalmology & Visual Science. 2012;53(4):1852-1860. doi:10.1167/iovs.11-9309 and in Chauhan BC,, O'Leary N,, Almobarak FA,, et al. Enhanced detection of open-angle glaucoma with an anatomically accurate optical coherence tomography-derived neuroretinal rim parameter. Ophthalmology. 2013; 120: 535-543
For the Cirrus OCT, the MRW is estimated over a continuum as data points are pulled from the data cube. The Cirrus OCT fits a plane to the BMO surface and uses that plane to characterize and correct for how the optic nerve is tilted relative to the retinal surface. Also, the Cirrus corrects for disc size when comparing ONH measurements to normative limits.
It is available from Cirrus OCT model 400 and 4000 (software version 5.0 onwards)
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Should ophthalmologists consider treatment options beyond intraocular pressure ? What will these options be? There is normotensive glaucoma also; what should the approach be in those cases?
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Currently, the only known modifiable risk factor for glaucoma is intraocular pressure(IOP) and hence is the focus of most physicians for glaucoma treatment.
But I understand why you ask this question as there is a paradigm shift in our understanding of glaucoma over the past 5 years or so. Newer drug classes like the ROCK kinase inhibitors, adenosine receptor agonists and newer prostanoid receptor agonists are also on the brink of entering markets after successful trials. Advanced modalities like SiRNA and Gene therapy has also been explored for glaucoma treatment.
What is important to note is the need for this research as glaucoma progression has been noted in several patients despite being maintained under target IOP and also invariably in NTG patients. The role of mematine, brimonidine and other neuroprotective agents has also been explored but results don't match up to the expectations. There is a lot to do yet but at the same time IOP is something that is imperative to control. These anti glaucoma drugs thus still have a very important, though quickly diminishing importance in explaining the patho-physiology of glaucoma, which unfortunately yet excitingly remains an elusive hunt for glaucoma researchers to pursue.
An excellent review of the newer drugs is attached for your reference.
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IT is a picture of the fundus. I am not sure about what is this indicative of and what landmarks should I take into consideration. I have acquired a lot of such images but I am not able to interpret them.
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Indeed - it is the holangiotic fundus of an albino rat or mouse. The nerve head and retinal vessels look normal - what are the clinical findings of the animal - is there any change in vision or behaviour?
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I am formulating a Ophthalmic eye drop solution and I want to claim that the eye drop contains a "Disappearing Preservative" that becomes water and Oxygen once in contact with the eye and the light, and that EDTA is used as a Chelating Agent. But if  I use the EDTA at 0,1% concentration, then the solution is no longer free of preservative once instilled in the eye. What justification can I give for the use of EDTA, so that the use of this agent is not viwed as a preservative?
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Dear Victor,
Do you have suggestion where I can find the SOC supplier who have GMP or they can state that their product is pharmaceutical grade?
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Hello everyone
I have some doubts about the short-term mechanisms of action of Rho kinase inhibitors on corneal endothelial cells. Can someone help me? I am not finding the information I need in the literature.
As you may know, Y-27632 has been extensively evaluated in pre-clinical studies aimed at the treatment of corneal endothelial lesions. The inhibition of the ROCK signaling pathway with Y-27632 results in inhibition of myosin light chain (MLC) phosphorylation, with subsequent inhibition of apoptosis of corneal endothelial cells. The literature shows that 100 hours after treatment with Y-27632, endothelial cell cultures show totally collapsed stress fibers and a significant reduction in the apoptotic index. However, I wonder what happens within the first 15-30 minutes after exposure of the cell to the Rho kinase inhibitor? Is any significant effect expected on cell metabolism or activities in such a short period of time? Finally, considering the rational clinical use of Y-27632 and possible ocular adverse effects (ocular hypotension, intense hyperemia, etc.) of its instillation, is inhibition of Rho/ROCK advantageous in which situations that affect the corneal endothelium? Would you use Y-27632 only to prevent cell loss in a healthy corneal endothelium?
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I am sending to your attention the following impactful papers
9 Jaffe AB, Hall A. Rho GTPases: biochemistry and biology. Annu Rev Cell Dev Biol 2005;21:247–69. 10 Zeng P, Pi RB, Li P, et al. Fasudil hydrochloride, a potent ROCK inhibitor, inhibits corneal neovascularization after alkali burns in mice. Mol Vis 2015;21:688–98. 11 Yin J, Yu FS, Fs Y. Rho kinases regulate corneal epithelial wound healing. Am J Physiol Cell Physiol 2008;295:C378–C387. 12 Sijnave D, Van Bergen T, Castermans K, et al. Inhibition of Rho-associated kinase prevents pathological wound healing and neovascularization after corneal trauma. Cornea 2015;34:1120–9. 13 Zhou Q, Duan H, Wang Y, et al. ROCK inhibitor Y-27632 increases the cloning efficiency of limbal stem/progenitor cells by improving their adherence and ROSscavenging capacity. Tissue Eng Part C Methods 2013;19:531–7. 14 Okumura N, Koizumi N, Ueno M, et al. The new therapeutic concept of using a rho kinase inhibitor for the treatment of corneal endothelial dysfunction. Cornea 2011;30(Suppl 1):S54–9. 15 Okumura N, Koizumi N, Ueno M, et al. ROCK inhibitor converts corneal endothelial cells into a phenotype capable of regenerating in vivo endothelial tissue. Am J Pathol 2012;181:268–77. 16 Galvis V, Tello A, Gutierrez ÁJ. Human corneal endothelium regeneration: effect of ROCK inhibitor. Invest Ophthalmol Vis Sci 2013;54:4971–3. 17 Siu GD, Young AL, Jhanji V. Alternatives to corneal transplantation for the management of bullous keratopathy. Curr Opin Ophthalmol 2014;25:347–52. 18 Koizumi N, Okumura N, Kinoshita S. Development of new therapeutic modalities for corneal endothelial disease focused on the proliferation of corneal endothelial cells using animal models. Exp Eye Res 2012;95:60–7. 19 Okumura N, Inoue R, Okazaki Y, et al. Effect of the Rho Kinase Inhibitor Y-27632 on corneal endothelial wound healing. Invest Ophthalmol Vis Sci 2015;56:6067–74. 20 Pipparelli A, Arsenijevic Y, Thuret G, et al. ROCK inhibitor enhances adhesion and wound healing of human corneal endothelial cells. PLoS One 2013;8:e62095. 21 Okumura N, Koizumi N, Kay EP, et al. The ROCK inhibitor eye drop accelerates corneal endothelium wound healing. Invest Ophthalmol Vis Sci 2013;54:2493–502. 22 Okumura N, Okazaki Y, Inoue R, et al. Effect of the Rho-associated kinase inhibitor eye drop (Ripasudil) on corneal endothelial wound healing. Invest Ophthalmol Vis Sci 2016;57:1284–92. 23 Chan W, Akhbanbetova A, Quantock AJ, et al. Topical delivery of a Rho-kinase inhibitor to the cornea via mucoadhesive film. Eur J Pharm Sci 2016;91:256–64
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Any practical resources available on use of image J for quantification of OCT, FA and OCTA images?
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There are numerous functions to quantify OCT and OCTA. For OCT you can quantify thickness, measure loss of EZ/OS (gray scale drop out).
or OCTA, you can measure capillary density, foveal avascular zone area, fractal dimension values, number of junctions (bifurcations), etc. The possibilities are endless. I would suggest to look at the literature to find what’s relevant to your work. Unfortunately I don’t know of a manual specific for OCT/OCTA quantification.
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I want to use it in order to explore dry eye symptom (Foreign body sensation,Itchy eye,Burning sensation,Teary eye,Photophobia,Red eye) reporting patterns and to better understand symptomatic heterogeneity in the study population.
how many group should I do and according to what the subjects can be put in groups ?
Note : each dry eye symptom was grade as 0 (none of the times ) , 1 ( some of the times) , 2 ( half of the times ) , 3 ( most of the times ) , 4 ( all of the times )
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The important point in dry  eye symptoms is the fact that we have different ocular surface problems that gives the same symptoms .I suggest to have a clinical diagnosis of the type of the ocular surface problem and analyze according  to a clinically documentable signs and symptoms
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What are all the Parameters consider for Phakic IOL Power calculation?
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A phakic intraocular lens (PIOL) is a special kind of intraocular lens that is implanted surgically into the eye to correct myopia (nearsightedness). It is called "phakic" because the eye's natural lens is left untouched. This is in contrast to intraocular lenses that are implanted into eyes after the eye's natural lens has been removed during cataract surgery.
Phakic intraocular lenses are indicated for patients with high refractive errors when the usual laser options for surgical correction (LASIK and PRK) are contraindicated
Phakic IOLs are designed to correct high myopia ranging from −5 to −20 D if the patient has enough anterior chamber depth (ACD) of at least 3 mm.[3]
Three types of phakic IOLs are available:
Angle-supported
Iris-fixated
Implantable Collamer Lens
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The new IOL master 700 has smaller in vivo repeatability SD for most metrics than the Lenstar, eg. 8µ instead of 35µ for AXL, 11µ instead of 40µ for ACD and 12µ instead of 80µ for lensthickness.
However, are these smaller standard deviations of clinical importance, i.e. to what extend would they contribute to a different choice of IOL power in in 'old' formulas like e.g. SRK-T and Holladay 1, and in new formulas, like e.g. Olsen or Barrett ?
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Greetings. Our experience with the IOL master 700 is favorable, although we believe that there are no significant differences with respect to the previously used formulas. For this we take a study at the moment to determine if it is actually more efficient. I also believe that regardless of the formulas that are very important to determine the power of the intraocular lens, the effective position of the lens and the incisions of surgery are determinant in the result.
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Retinal surgery utilises the viewing system of operating microscope and various additional lenses. Visualisation becomes a challenge If the viewing lens becomes fogged.It is mainly due to water vapours present in operating room and patient's breath. How can this be eliminated so that surgery can proceed uninterrupted?
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Here are some tips:
  • Ask assistant to press the drape over patient's nose to stop passage of air from patient to operating field. 
  • Move the lens a bt away from the surface of the cornea (be aware that this reduces the field of view).
  • anti-fogging coat doesn't help much and probably is not suited for repeated  sterilisation process
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How to get good grades in the examination of RNFL peripapillary in OCT, because in most cases the note is yellow and it decreases the confidence in the result.
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Thank you for all remarks about my question!
Best Regards
Romar
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Cataract Surgery
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You can tape them to the eye drapes. Would you not manage better with an Ahmed capsular tension segment hold in place with an iris hook and place a permanent CTR at the end?
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Ophthalmologists often order FFA in uveitis cases. When should it be done and how does it help in management ?
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Good discussion. I agree with Dr Marianne regarding indication for OCT, but FFA is useful in various uveitic conditions and at various stages as described in books if not all. 
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A comparative study with various post operative inflammatory parameters has shown
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It depends on individual case. Even then some cases with absolutely no reaction respond to NSAID drops initially, some require steroid drops intensively at the end of PO first week. This is due to multi factorial causes.
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What are the common conditions you come across
Newer techniques in diagnosis and management?
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I  diagnosed different stages of ocular SCC in white faced cows either invasive or non invasive also that involved third eyelids or bulbar and palpebral conjunctiva.  
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It is used in ophthalmology surgeries 
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@ Selim- You can buy it from us at Next Biosciences: fikile.mnisi@nextbio.co.za. and yes it is used in Ophthalmology. or contact us at +27 11 697 2900 and ask for Fikile.
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As in the subject - do you know any comercial systems for computer-based campimetry/perimetry, where light stimuli are displayed on the flat computer screen? I know only common perimeters based on the hemispherical surface stimuli presentation, such as Humphrey Field Analyser or Medmont M700. I'm also familiar with the software for psychophysics listed at http://www.hans.strasburger.de/psy_soft.html.
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Great advancements in science
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Retinally induced aniseikonia may be an increasingly important cause of visual symptoms with the aging of the population (Rutstein, 2012). The prevalence of RIAk is unknown because it is not routinely teste in the clinic. Are there any differences by 2012?
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Hello, the most recent reports on retinal aniseikonia seem to be exclusive for the disease groups mentioned before. Here are some articles on RA and ERM.
Hope this helps
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As,Tracheal bleed during intubation from tracheal erosion,bronchial spasm,apnea etc,high INR,superadded infection,compromised immunity,etc etc.... makes decision making little troublesome in such cases, especially to me often. If anybody has any experience ?please share.
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Lot of thanx to u Sir for your opinion. I have got excellent outcome with few such acute cases of SJS ( mostly because of anticonvulsants), in my experience, which I didn't get in chronic/late cases. But, many a times I have seen anaesthetist would like to defer the case either because of high INR or deranged coagulation profile or fear of tracheal bleed during intubation, which hinders the ocular prognosis. Can u please share your experience in doing bedside AMG procedure (as I have no such experience), particularly in children who doesn't allow to even touch their eyelids during acute stage. Thanking u again. Sincere regards- S. Dasgupta.
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As found in the literature The OSDI is a valid and reliable instrument for measuring dry eye disease it is assessed on a scale of 0 to 100, with higher scores representing greater disability. The overall OSDI score defined the ocular surface as normal (0-12points) or as having mild (13-22 points), moderate (23-32 points), or severe (33-100 points) disease.
I think the cutoff should be > 12 , is it correct ?
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The original OSDI questionnaire includes 12 questions. the score for each question ranges from 0 to 4. The formula used to calculate the final OSDI score includes both the number of questions answered and Sum of Scores for All Questions Answered. OSDI score ranges between 0-100 but because some questions may not be applicable to some responders, we can not determine a clear cut off, and cut off level varies based on number of questions answered and sum of scores for all questions answered. the final nomogram looks like a color spectrum ranging from white to orange, light red and finally dark red. The bottom line is when you calculate your patient's score you should look at the nomogram to judge where her/his score falls in the nomogram and judge about severity of dry eye.
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Hi,
I currently work with the Ophthalmology department at the University of Illinois at Chicago. I have some ideas in mind which would require a Magnetic hyperthermia instrument.
I was wondering if anyone knows who has the equipment in the city so that I could contact them and look for a collaboration or solicit them to use the machine
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Hi Debra, Thank you for teh reply. I was able to get in touch with some good folk. However the machines are either not operational or they do not give access to outsiders
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Megapixel of human eye
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Capacity of Human eye cannot be computed but by some maths, you can have some judgement about how amazing and unlimited it is.
You can refer following link:
they have shown that how it comes to 576MP for human eye.
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We need a young and updated researcher in the field of eye research. We need his/her clinical knowledge to complete our discussion section in a manuscript pertinent to eye and ophthalmology. Please contact me for further information.
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I would be interested in  your research.  I am a clinical scientist, having  research experience in corneal physiology. I worked as a Post Doc at Oxford University and  obtained a PhD From UMISTt having worked under Professor Nathan Efron.  I am an active clinician and I am  currently involved in ocular therapeutics.   You could contact me on bay811@ yahoo.com
Kind Regards
Dr  S. Amirbayat
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In order to design assistive device based on the movement of eyeball, how to detect the various angle between two different motion.
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Hi Ranvijay,
There are few other methods for detection of Eye movements like
  • Infra-red oculography
  • Image based method
  • Scleral search coils
Go through following article. It may help you:
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We all like brand new charts for our clinics and trials etc. but I have a number of old charts - either yellowed plastics or grubby looking Pelli Robson's etc. I'm struggling to find anything on the published shelf-life of these products. Can anyone assist? 
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Thank you - I agree, but can I find any recommendation from the manufacturers on shelf life? None at all. I have it in my head that the photographic paper of the Pelli Robson has a shelf life of 2 years but I can't find reference to it anywhere. In the meantime at the hospital we still have the oldest, based and yellowed charts imaginable. Tsk tsk..   For research purposes we now have a rather expensive looking photometer. 
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What is the protocol for amniotic membrane preparation and cryopreservation for corneal transplant healing? I only found old protocols (90's-2000's) with reference numbers that are no longer available from different companies...
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Following reference articles may solve your query regarding latest protocols.
Preparation of amniotic membrane for ocular surface reconstruction
Effects of different cryopreservation methods on the ultrastructure and viability of amniotic membrane 
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Flomax causes Intra-operative floppy iris during cataract surgery. Does it effect zonules in any way?
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Flomax in particular has no effect on zonules as there are no such receptors on lens zonules for FLOMAX to bind.
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In humans it stays upto 24hrs to 72hrs and I'm expecting it to be longer in rats. I'm using a 2% homatropine hydrobromide solution for an experiment on rats and i want to know the dosing interval for continuous mydriasis. I need it for 9 days straight but sadly atropine eye drops, here, are not in production any more.
Is it safe to assume that it acts longer or more potent? Any precautions to keep in mind?
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Dear Vasishata,
From the literature it is revealed that the duration of action in rats is not more than 12 hours when homatropine was given by intramuscular injection, oral gavage and rectal suppository (the value might be a little lower or higher but it does not reach 24-72 hours).
For more on this, please see the following:
J Pharm Pharmacol. 1978 May;30(5):284-6.
Rectal absorption of homatropine [14C]methylbromide in the rat.
Cramer MB, Cates LA, Clarke DE.
Abstract
Homatropine[14C]methylbromide (HMB-14C) was administered to rats by intramuscular injection, oral gavage and rectal suppository. Plasma concentration of 14C were measured over the subsequent 12 h. Peak plasma concentrations were higher and achieved more rapidly after rectal administration than by the other routes whether HMB-14C was administered in a water-soluble suppository base or in aqueous solution. Twelve h after the suppositories were inserted and retained 28% of the 14C had been excreted in the urine while 56% remained in the large intestine. Unlabelled HMB, given in rectal suppositories to anaesthetized rats, caused prompt blockade of the effects of vagal stimulation on pulse rate and of intravenous acetylcholine on blood pressure. These results confirm the rapid rectal absorption of the drug.
Hoping this will be helpful,
Rafik
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Does your hospital has any guideline for preoperative PHARMACOLOGY management of cataract or glaucoma surgery?
I am trying to collect as many opinions from all over the world
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Local:  Topical Paracaine/lignocaine or peribulbar block . Povidone Iodine paint .
Topical broad spectrum antibiotics starting a day before surgery , dilating agent(Tropicamide phenylephrine) on day of surgery with or without flurbiprofen. Antiglaucoma drugs for glaucoma cases ( Stop prostaglandins and pilocarpine atleast 7 days before surgery)
Oral: Minimal dosage of wide spectrum antibiotics in susceptible cases, analgesics as per need, oral acetazolamide as per surgeon and the case
Regards - Dr Lipi Chakrabarty, Director LIPIKA NETRADHAM, Bhilai-Durg, Chhattisgarh, India
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I want to induce retinal degeneration in vitro in a specimen of goat's eye. Which chemical can be used for the purpose?
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The latest approach Intravitreal injection of sodium iodate best results with 0.8mg
Good luck !
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What could cause autologous serum eye drops to precipitate? A patient has been using the drops for years due to dry eye symtpoms. Recently, three of four production series tended to precipitate when being thawed. Cold agglutinines, cryoglobulines, bacterial contamination was ruled out by lab examinations. FVIII (as one of the factors in cryoprecipitate) was only slightly elevated to 180% (upper norm limit is 150% at our lab). Electrophoresis of serum proteins was normal...any suggestions?
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trehalose, mannitol, sorbitol are among cryoprotectants  you could safely use for that particular application. 
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At present the new indication exists - Age-related macular degeneration and ocular trauma
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I am trying to find any information about number of performed vitrectomies world wide as well cataract surgeries?
Do we have everyday increasing number of vitrectomies? Is there any data or any article to compare these important two aspects?
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Cataract Surgery is the leading surgery performed in the field of Ophthalmology. Vitrectomy is no way comparable to the number of catarct extractions performed worldwide. But the percentage of Vitrectomies is on the rise due to more trained personnel available in the field I.e. there are more vitreoretinal surgeons today than in the past years and they treat many retinopathies with Vitrectomies. Since the prevalence and incidence of Diabetic retinopathy is increasing worldwide, the number of Vitrectomies is expected to increase but not in proportion to That of cataract surgeries. 
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This question is bothering me , as I am doing a work which concentrates on the study of damage in fovial region of human eye.
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The Fovea is a centre of Macula -area  of the retina responsible for the Central vision- fine vision ability to see an object clearly, characterised by Visuall  Acuity and Color Vision. Only cones are highly concentrated in macula and each cone has his own representative in the brain. Fovea is a physiological depression and has only a half fickeness (5 layers) comparing to the rest of retina - 9 or somewhere mentioned 10 layers. Lesion in the foveolar area causes central scotoma in Visual field testing named perimetry.
With very best wishes for your rearch
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After placement of an orbital implant in enucleation, the anterior layers (ant Tenon's and conj) are simply closed. <br />
In the interest of increasing (eventual) ocular prosthesis motility, would it be advantageous to tack these layers together?<br />
Perhaps with an alcohol to denature some fat, followed by a mild caustic, suctioned, then irrigated-out?
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Thank you for your comment. Yes, these layers are generally sutured individually. My 2013 question is directed to maximizing ocular prosthesis motility after enucleation.
When, as in the currently usual manner, an orbital implant is placed behind posterior Tenon's capsule to increase tissues over the implant, the nature of anterior Tenon's capsule implies a lubricity between it and the posterior layer. This altered anatomy seems to me to be invoking a slip-space that may reduce the translation of motility from the implant to the subsequent ocular prosthesis. Thus, scarring these layers together might aid motility.
Whether it makes sense to reduce movement between these over-layers to increase motility is debatable. Some surgeons, conceiving that motility is induced primarily from the conjunctival fornices, recommend a sutural bite into the fornix.
Any assistance to symmetrical motility would greatly aid the patient's future appearance.
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Globally, the magnitude of occurrences of Pterygium is over 200 million people and the prevalence varies between 0.3 % and 37%.[i]  The fact remains that ocular disorders are caused by the reflected solar radiation from the surface of the earth especially the white and shining surfaces such as snow and water. [ii]
My question is what percentage of Out Patient cases in hospital undergo surgeries?
[i] Lu P, Chen XM., Prevalence and risk factors of pterygium. Int J Ophthalmol 2009;2(1):82-85
[ii] Bergmanson JP, Soderberg PG. The Significance for Ultraviolet Radiation for Eye Diseases. A review with comments on the efficacy of UV Blocking Contact Lenses. Ophtahlmic Physiol.Opt. 1995; 15: 83-91.
Relevant answer
Answer
In my own experience most of the females patient opt for surgical treatment. Males being bit reluctant; overall it would be approximately 65% undertaking surgery.