Downloaded 38 times
Uploaded byMohamed Elbarghathi
REFRACTIVE SURGERY.pptx
This document discusses the various techniques used in refractive surgeries to correct vision, including steps for evaluating patients and determining suitability. It describes the history and evolution of refractive surgeries. The main techniques covered are corneal-based procedures like LASIK, PRK, and SMILE as well as lenticular procedures using phakic intraocular lenses. For LASIK specifically, it outlines the surgical technique and potential complications. Contraindications for refractive surgeries are also stated.
More Related Content
Similar to REFRACTIVE SURGERY.pptx
REFRACTIVE SURGERY.pptx
- 1. Refractive Surgery Dr. Mohamed FElbarghathi By Assistant lecturer , Ophthalmology department Faculty of medicine, University of Benghazi
- 2. Explain the steps- including history, ocular examination, and investigations - in evaluating whether a patient is an appropriate candidate for refractive surgery. 1 INTENDEDLEARNINGOUTCOMES“ILOs” Identify the various techniques used in refractive surgeries. 2 For (LASIK), describe surgical techniques and complications. 3 State possible contraindications to corneal based refractive surgery in patients with pre-existing ocular or systemic disease. 4
- 3. Refractive surgeries INTRO Group ofprocedures that may be surgical or laser assisted, on cornea or lens. The surgeries on cornea are done far more frequently than on the lens Principle in corneal refractive surgeries is to change the corneal curvature to change its refractive power Some of the eyes that may benefit visually by surgery cannot be operated due to existing contraindications.
- 4. Refractive surgeries HISTORY 1965 19701983 1991 1996 JOS - IGNACIO BARRAQUER Introduction of Keratomileusis . FYODOROV invents Radial Keratotomy Invention of the Excimer Laser PRK and LASIK approved by FDA SLADE / BRINT 1ST LASIK surgery Evolution of Femtosecond Laser in Refractive Surgery 2001
- 5. Refractive surgeries CLASSIFICATION CORNEA BASED R.K 01 PRK 02 LASIK 03 SMILE 04 LENTICULARBASED PHAKIC APHAKIC IOL CLEAR LENS EXTRACTION >45Y PHAKIC IOLs (Young) AC PC BIOPTICS Combination of the two
- 6. Refractive surgeries Preoperative assessment(History ) Corneal ectasia (KC) January December
- 7. Refractive surgeries Preoperative assessment(History ) Why age is important ? Ranges between 20 and 45 years Under 20 years have higher chances of being unstable over 45 years have following drawbacks: 01- Is the age of presbyopia. 02- Many of them will develop lenticular changes ( Cataract).
- 8. Refractive surgeries Preoperative assessment(stabilization ofrefraction ) The procedures should be done only on eyes that have unchanged errors of refraction, at least 1 year prior to surgery. January December
- 9. Refractive surgeries Preoperative assessment(Contraindications) Absolute C/I Infection 01 Keratoconus 02 Glaucoma 03 Posterior segment anomalies 04 Immune suppression 05 Amblyopia 07 Corneal dystrophies 06 Relative C/I Dry eyes 01 Allergic keratoconjunctivitis 02 Diabetes mellitus 03 Pregnancy 04
- 10. 1- No improvement. Organicpathology , Amblyopia Pin hole 2- Improvement. Refractive surgeries Preoperative assessment (Visual acuity&Refraction)
- 11. Subjective assessment of Refractiveerror and BCVA Objective measurement of Refractive error Visual acuity measurement UAVA Refractive surgeries Preoperative assessment (Visual acuity&Refraction)
- 12. BCVA 02 UAVA 01 Refractive surgeries Preoperative assessment(Visual acuity&Refraction)
- 13. Cycloplegia should beperformed to all cases . to refine the sphere. By neutralizing accommodation . Refractive surgeries Preoperative assessment (Visual acuity&Refraction)
- 14. LASIK (Sphere) +5.00TO -14.00 D (Cylinder) Up to 5.00 D PRK (Sphere) +6.00 TO -12.00 D (Cylinder) Up to 4.00 D Phakic intraocular lens (Sphere) –3.00 to –20.00 D (Cylinder) Up to 4.00 D Toric lens Refractive lens Exchange (Sphere) All ranges (Cylinder) Up to 4.00 D toric lens Refractive surgeries Preoperative assessment (Visual acuity&Refraction) Reference : 2022-2023
- 15. Rule out anyof these : Corneal dystrophy. Vascularization. Active HSV . Corneal ectasia .”Keratoconus” Refractive surgeries Preoperative assessment (Identifies aCo-Pathology) Cornea
- 16. Rule out anyof these : Cataract. Ant or Post Lenticonus Lens Subluxation Refractive surgeries Preoperative assessment (Identifies aCo-Pathology) Lens
- 17. Tear meniscusheight . Tear film break up time . Schirmer test . EXCLUDE :- Severe dry eye . Autoimmune disease . Refractive surgeries Preoperative assessment (Identifies aCo-Pathology) Pre ocular tear film
- 18. Dilated Fundus Exam Essential Refractivesurgeries Preoperative assessment (Identifies aCo-Pathology)
- 19. Corneal Tomography. Refractive surgeries Preoperativeassessment (Investigation) Keratometry measurements 01 Corneal thicknes measurements 02 Pentacam
- 20.
- 21. Radial keratectomy Series of4-8 deep, radial corneal stromal incision 01 Weaken the paracentral & peripheral cornea & flatten the central cornea 02 Complications • Bullous keratopathy • Low stability of refraction
- 22.
- 23. PHOTOREFRACTIVE KERATECTOMY (PRK ) Outer layer of cornea is removed then excimer laser is applied. 01 No flap created 02 Vision improves as surface heals from 7 to 21 days. 03 Longer recovery period (> 2 weeks) 04 Discomfort present during healing 05
- 24.
- 25. LASIK (Laser-assisted insitu keratomileusis) Most commonly performed refractive surgery 01 Excimer laser ablation of corneal stroma beneath a corneal flap that is created with a mechanical or femtosecond laser microkeratome 02
- 26. LASIK (Laser-assisted insitu keratomileusis) Steps of LASIK Flap creation Apply excimer laser Flap returned
- 27.
- 28.
- 29.
- 30. Unwanted astigmatism 05 Corneal ectasia 04 Flapcomplication 03 Epithelial trauma 02 Under/over correction 01 Laser vision correction complications
- 31. Excimer & Femtolaser machine
- 32.
- 33.
- 34. Phakic Intra ocularlenses (IOL) Artificial lenses implanted in the anterior or posterior chamber in the presence of the natural crystalline lens to correct refractive errors. Types •AC iris-fixated ( Artisan ) •Posterior chamber IOL ( ICL )
- 35. AC iris-fixated (Artisan )
- 36. Posterior chamber IOL(ICL )
- 37. Complication of phakicIOLs PC IOLs - Pupillary block . - Dislocation. - 2ry Glaucoma . - Iritis, Cataract. AC IOLs - Pupillary block . - Dislocation. - 2ry Glaucoma . - Iritis.
- 38.