Utilizing topolyzer vario & oculyzer ii for accurate refractive
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This document discusses the use of TopolyzerVario and Oculyzer II devices to provide accurate measurements for refractive laser eye surgery. It provides details on the essential data required by the ex500 laser including pre-operative and post-operative corneal measurements. The accuracy of the TopolyzerVario and Oculyzer II is impacted by factors like corneal irregularities, eyelashes, and light scattering. Ensuring accurate measurements from these devices is important for achieving good refractive predictability and visual outcomes with laser eye surgery.
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IOL power calculation is challenging in eyes with prior refractive surgery or other special situations. In eyes with prior radial keratotomy, standard keratometry overestimates corneal power due to flattening outside the central optical zone. Multiple methods of IOL power calculation should be used, including topography to measure the flattest central corneal power. A study comparing methods in eyes with prior RK found IOL power calculation using topographic keratometry was least accurate compared to formulas from the ESCRS calculator. No single method provided reliable results, highlighting the difficulty in IOL power calculation for eyes with prior refractive surgery.
DIAGNOSTICS-IMPACT ON THE PREMIUM CHANNEL - Carl Zeiss Meditec AG
The document discusses how advances in diagnostic technology have reduced refractive surprises following cataract surgery. It notes some remaining challenges and outlines technologies from ZEISS that further address these issues:
1. The IOLMaster 700 allows biometry measurements in over 99% of patients, significantly reducing the need for less precise ultrasound measurements.
2. The IOLMaster 700's improved repeatability results in more consistent measurements, potentially reducing refractive outcomes by over 0.3 diopters.
3. The IOLMaster 700's fixation check can help detect unusual eye structures and prompt further OCT examination.
4. The CALLLISTO eye and Cataract Suite markerless combine the IOLMaster 700's reference image
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EUR毕业证offer【微信95270640】《鹿特丹伊拉斯姆斯大学毕业证书原版制作EUR成绩单》【Q微信95270640】《仿制EUR毕业证成绩单鹿特丹伊拉斯姆斯大学学位证书pdf电子图》，A.为什么留学生需要操作留信认证?
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B.为什么我们提供的毕业证成绩单具有使用价值？
查询留服认证是国内鉴别留学生海外学历的唯一途径，但认证只是个体行为，不是所有留学生都操作，所以没有办理认证的留学生的学历在国内也是查询不到的，他们也仅仅只有一张文凭。所以这时候我们提供的和学校颁发的一模一样的毕业证成绩单，就有了使用价值。
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6:个人职称评审加20分
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Utilizing topolyzer vario & oculyzer ii for accurate refractive
- 1. We focus your ideas Utilizing TopolyzerVario & Oculyzer II for IROC Science to Innovation AG Technoparkstrasse 1 8005 Zürich Tel: +41 43 500 0850 accurate refractive outcomes Michael Mrochen, PhD
- 2. VISION - OPTICS - LIGHT Content • What essential data are required by your ex500? • What is different between WFO and T-CAT? • A limiting factor: the subjective refraction • Accuracy of the TopolyzerVario • Accuracy of the Oculyzer II • A small pocket guide on: What to use when? 2
- 3. VISION - OPTICS - LIGHT What essential data are required by your ex500? • Ablation profile – A map of required tissue removal at each point of the cornea – It’s based on difference between the pre- and to post-operative cornea anterior surface – Derived from either modelled or measured anterior cornea data 3
- 4. VISION - OPTICS - LIGHT What essential data are required by your ex500? • How to calculate an ablation profile? – Assume a preoperative cornea shape (R,Q, Cyl,…) – Calculate the postoperative corneal shape based on the attempted refractive power change – Define to optical zone – Calculate the change in corneal height maps within the optical zone – Define a transition zone 4 Preoperative Postoperative Optical zone
- 5. WFO Wavefront Optimized for sphere and cylinder T-CAT Topography guided for sphere, cylinder and corneal irregularities VISION - OPTICS - LIGHT What is different between WFO and T-CAT? 5 Ex500 Algorithm Manifest Refraction Optical zone WFO Ablation profile - Refractive predictability - Maintain visual performance Ex500 Algorithm Manifest Refraction Optical zone T-CAT Ablation profile - Refractive predictability - Improve visual performance Height maps from Topolyzer / Oculyzer
- 6. Error of refraction (normal eyes) 60% [43% to 75%] ±0.25 92% [80% to 98%] ±0.5 100% [91% to 100%] ±1.0 VISION - OPTICS - LIGHT A limiting factor: the subjective refraction Error of refraction (irregular cornea) 25% [18% to 33%] ±0.25 50% [41% to 58%] ±0.5 80% [72% to 86%] ±1.0 Thomas W. Raasch1, Kenneth B. Schechtman2, Larry J. Davis3, Karla Zadnik1 Repeatability of subjective refraction in myopic and keratoconic subjects: results ofvector analysis. Ophthal. Physiol. Opt. Vol. 21, No. 5, pp. 376±383, 2001
- 7. VISION - OPTICS - LIGHT Accuracy of the TopolyzerVario 7 44Edges Edge Detection
- 8. VISION - OPTICS - LIGHT Accuracy of the TopolyzerVario 8 Eye lashes, lid & nose Corneal irregularities Pupil detection Corneal surface / tear film
- 9. Degree of light scattering is of clinical relevance VISION - OPTICS - LIGHT 9 Accuracy of the Oculyzer II
- 10. VISION - OPTICS - LIGHT Accuracy of the Oculyzer II 10 Segmented measurement Motion compensation Light scattering
- 11. VISION - OPTICS - LIGHT Consequences of accuracy 11 Uncertainty of topography ~ 2 - 5 microns @ 8 mm 2 micrometer will result in an uncertainty of approximately 0.14 D for an optical zone of 6.5 mm 2 micrometer will result in an uncertainty of approximately 0.98 D for an optical zone of 2.5 mm
- 12. VISION - OPTICS - LIGHT A small pocket guide on: What to use when? 12 Manifest Refraction How much can I trust the Rx? TopolyzerVario Measurement Oculyzer II Measurement Mires of rings well detected? Yes Scheimpflug images well detected? Successful Topolyzer or Oculyzer measurement? No ex500 Yes No Other treatment options
- 13. VISION - OPTICS - LIGHT Summary • TopolyzerVario and Oculyzer II are accurate measurement devices as demonstrated by experimental measurements and clinical studies. • Measurements of each device can be affected differently by the condition of the patient’s eye. • Raw data checks are required to assure accurate measurements. • Consequences can be irregular ablations or poor refractive predictability 13