医学英语课件资料：Corneal Transplantation

1、Free Powerpoint TemplatesCorneal TransplantationFrameworkIntroductionEpidemiologyHistoryIndication Anatomy (major: bullous keratopathy & keratoconus )Equipment & instrumentOperationObjectivePre-operative treatmentPerforating keratoplasyIdentificationIndicationPreservation of donor corneaProcedureLam

2、ellar keratoplasyIdentificationIndicationPreservation of donor corneaProcedurePost-operative treatmentDifferences between PK and LKMaterial ComplicationsIntraoperative complicationPostoperative complicationLong-term complication(major: cornea rejection)Other problemsResearch hotspotHigh speed lasers

3、Better surgical skillsCorneal stem cellsBiosynthetic corneasIntruoductionCorneal transplantationsurgical procedurereplace a diseased cornea with a new one2 major categoriespenetrating keratoplasty (穿透角膜移植术, PK) entire cornea replacedlamellar keratoplasty (板层角膜移植术, LK)part of the cornea replacedIntro

4、ductionEpidemiologyEpidemiologyOliva M S. Turning the tide of corneal blindness.J. Indian Journal of Ophthalmology, 2012, 60(5):423-427.EpidemiologyGullapalli N. Rao, Corneal Opacification in the Developing World. Duanes Ophthalmology M, 2006. EpidemiologyEye bankan autonomous organizationpromote pu

5、blic awareness about eye donationtissue harvesting, evaluation, presentation, distribution.100,000 corneal transplantations worldwide per year10,000,000 people benefit from corneal transplantationsHistoryHistoryIndicationAnatomyNo blood vessels5 layersIndicationBullous keratopathy KeratoconusSevere

6、corneal ulcers caused by bacterial, fungal, parasitic or viral eye infectionSevere traumatic injuries that pierce or cut the corneaChemical burns of the eyeCorneal scarsFailure or rejection of a previous corneal transplantIndicationBullous keratopathy (大泡性角膜病变)swelling, blistering corneaendothelial

7、cells damagedpossible causesFuchs dystrophytraumaIndicationKeratoconus (圆锥角膜)degenerativedisordermiddle of the cornea thin, conical shapeIndicationvision deterioratedmultiple imagessensitive to lightetiology remains uncleargenetic, environment, cellular .?Equipment & InstrumentEquipment & Instrument

8、surgical microscopeophthalmologic operating tableEquipment & Instrumentcorneal forcepscorneal scissorseyelid speculumcorneal trephineEquipment & Instrumentcorneal forcepscorneal scissorseyelid speculumcorneal trephineEquipment & Instrumentcorneal forcepscorneal scissorseyelid speculumcorneal trephin

9、eEquipment & Instrumentcorneal forcepscorneal scissorseyelid speculumcorneal trephineOperationObjectiveOptical purpose To improve visual acuity by replacing the opaque or distorted host tissue by clear healthy donor tissue. Tectonic/reconstructive purpose To preserve corneal anatomy and integrity in

10、 patients with stromal thinning and descemetoceles, or to reconstruct the anatomy of the eye.Therapeutic purpose To remove inflamed corneal tissue unresponsive to treatment by antibiotics or anti-virals.Cosmetic purpose To improve the appearance of patients with corneal scars that have given a whiti

11、sh or opaque hue to the cornea. Preoperative treatment Preoperative care 3d before: eyedrop with antibiotics. 1d before: eye irrigating and washing of lacrimal passage and conjunctival sac. 1d before(at bedtime): eyedrop with miotics, e.g eserine, pilocarpine. 30min before: Intravenous drip with 20%

12、 mannitol, 250ml.Anesthesia Local anesthesia: retrobulbar or orbicularis oculi anaesthesia. 0.75%bupivacaine + 2% lidocaine + hyaluronidase 2.5U/mlPerforating keratoplastyWhat is Perforating KeratoplastyReplacement of full-thickness section of host cornea with a transparent cornea tissue from a huma

13、n donorRetainingthe peripheralcornea.Perforating keratoplastydevelopment abnormality keratoconus congenital opacities corneal dystrophies extrinsic damage mechanical trauma chemical injuries severe cases of microbial keratits noninfectious ulcerative keratitisWho will choose Perforating Keratoplasty

14、Moist chamber methodExtirpation of eyeball within 2-4h after deathPreserved with aline pledget, 4。Transplantation in 48h.M-K medium methodCuting of cornea with some sclerotic tissuesPreserved in M-K medium, 4。Transplantation in 34dExaming by specular microscope before transplatationPreservation of d

15、onor corneaPerforating keratoplastyPerforating keratoplasty Draping Eyelid separation Preparation for grafting bed Preparation for grafting cornea Suturing Reconstruction of anterior chamber Administration of antibiotics and steroids ProcedurePerforating keratoplastyWhat is Lamellar KeratoplastyRepl

16、ace diseased layers of the cornea while leaving healthy layers in placeDeep layer remains as planting bedsTake the cornea material with the same size and the thickness, sew on the corneal woundALK and DLKLamellar keratoplastyWho will choose Lamellar KeratoplastyLamellar keratoplastyShallow walleyeKe

17、ratitis, corneal ulcer, corneal fistula, tumorcorneal degenerationcorneal dystrophyPatients with psychiatric disease or nystagmus.Patients with strongimmuneresponses.Lamellar keratoplastyGlycerine dehydration method:aseptic stripping lamellar keratoplasty; saline rinses; 24h then transferred in pure

18、 Glycerin, sealedFormaldehyde solution method: sterile removal of eye operations; put 0.25% in a formaldehyde solution, sealed 4 preservation.Must be used within three months, with antibiotic rinses prior to use.Preservation of donor corneaLamellar keratoplastyThe operation(1)Lamellar keratoplastyTh

19、e operation(2)Postoperative treatment Wear eye shield for a few weeksRestoration of vision is gradualHave regular check-upsUse eye medications for many monthsWash hands with soap and water before putting in the drops.How to use eye dropsPull down the lower lidwith one finger, forminga “pouch” as sho

20、wn.Look up. How to use eye dropsPut one drop in the“pouch” of the lid. Donot touch the top of thebottle to the lid. If thedrop does not go intothe eye, try again.Close eye for one fullminute after each drop Lamellar keratoplasty vs PenetratingkeratoplastyPenetratingkeratoplastyLamellar KeratoplastyO

21、pticaleffectsSuccess is good, butif failed, it will be worseInterfacebetweengraftandplantingbedsis wide,affecttheopticalresultsTherapeuticpurposesEndothelialdegenerationfungalcornealulcers occurredTreatorimprovesubstrateContraindicationsMental illness,Walleyeassociated withneovascularization, Cornea

22、lthinning,Theonlyvisual acuityless than0.02High eye pressureChoiceofmaterialsStrict,cornealendothelium activityLong-term preservedmaterialsis OKOperationVery difficultSafe,simpleComplicationsMoreLessMaterialMaterialAutologousin the same corneal, transplant the health part to the bad partAllograftfro

23、m eye banks, and in widely clinical applicationsXenograft chickens, geese, monkeys, fish, dogs and other animals line of treatment of lamellar transplant to be successfulArtificial corneaspoly methyl methacrylate (PMMA), acrylic, silicone, Hydrogel, mineral glass, etcComplication Intraoperative comp

24、lications Postoperative complications Long-term complications cornea rejection Other problemsComplicationIntraoperative complication Insufficient anesthesia Eye movement, eyelid tension Bad fixed eyeball Incision bleeding Highly vascularized receptor cornea lens injury suture Level of organization d

25、islocation Sew iris by mistake Suture fracture Postoperative complications Graft failure Opacities Infection bacteria or fungi Broad spectrum antibioticsagainst common bacteriaPseudomonas aeruginosa fungi Hyphema眼前房积血 Highly vascularized receptor cornea Anterior chamber disappear Corneal epithelial

26、heal badLong-term complication Cataract 白内障 Preexist cataract Intraoperative injury Overuse glucocorticoid Glaucoma 青光眼 Chamber angle damage High intraocular pressure Corneal vascularization Vitreous adhesion Graft rejection immune privilege 免疫赦免 tolerate antigens without immune response lack of vas

27、culature relative immune separationOcular immune systemCorneal rejection signs and symptoms(RSVP) Redness Sensitivity to light Vision changes Pain Asymptomatic in mild cases Rate 10% in the short term A third within the first five years higher risk Binoculus transplants Repeated transplantsCorneal r

28、ejection Types Epithelial rejectionself-limited process Stromal rejection Endothelial rejectionsevere Age Old patients have fewer rejectionBy Mayo Clinic/tests-procedures/cornea-transplant/basics/what-you-can-expect/prc-20014357Corneal rejectionrejection treatment epithelial and stromal rejection tr

29、eatment topical corticosteroids, 4-6 times/d (eg, dexamethasone 0.1%, prednisolone acetate 1%) cyclosporin A slow tapering of the topical medication follow up Improving signs of rejection Without endothelial rejectionCorneal rejection endothelial rejection treatment Topical corticosteroids (eg, dexamethasone 0.1%, prednisolone acetate 1%) Every hour while awake As frequently as possible at night for 2-3 days followed by every 2 hours while awake cyclosporin A Steroid ointment Follow up Continue until sign