Special therapies in ophthalmology


Published on

Published in: Education
No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • Ocular pharmacotherapeutics can be delivered by
  • Special therapies in ophthalmology

    1. 1. Special therapies in Ophthalmology Gauri S. Shrestha, M.Optom FIACLE
    2. 2. What are they? <ul><li>Optical </li></ul><ul><li>Medical </li></ul><ul><li>Surgical </li></ul><ul><li>Laser </li></ul><ul><li>Cryotherapy </li></ul><ul><li>Vision therapy </li></ul>
    3. 3. Optical therapy <ul><li>Refractive errors </li></ul><ul><ul><li>Hypermetropia </li></ul></ul><ul><ul><ul><li>(long sightedness) </li></ul></ul></ul><ul><ul><ul><li>Light rays coming from infinity is focused behind the retina when accommodation is at rest </li></ul></ul></ul><ul><ul><li>Myopia </li></ul></ul><ul><ul><ul><li>(short sightedness) </li></ul></ul></ul><ul><ul><ul><li>Light rays coming from infinity is focused infront of the retina when accommodation is at rest </li></ul></ul></ul>
    4. 4. Optical therapy <ul><li>Refractive errors </li></ul><ul><ul><li>Astigmatism </li></ul></ul><ul><ul><ul><li>Refraction varies in different meridians </li></ul></ul></ul><ul><ul><ul><li>The rays of light entering in the eye can not converge to a point focus </li></ul></ul></ul>
    5. 5. Optical therapy <ul><li>Anomalies of accommodation </li></ul><ul><ul><li>Paralysis of accommodation </li></ul></ul><ul><ul><li>Presbyopia </li></ul></ul><ul><ul><ul><li>Physiological insufficiency of accommodation </li></ul></ul></ul><ul><ul><ul><li>Normal phenomenon according to age </li></ul></ul></ul><ul><ul><li>Insufficiency of accommodation </li></ul></ul><ul><ul><ul><li>Abnormal insufficiency of accommodation </li></ul></ul></ul>
    6. 6. Optical therapy <ul><li>Strabismus </li></ul><ul><ul><li>Accommodative esotropia </li></ul></ul><ul><ul><ul><li>Esotropia caused by excessive abnormal accommodation </li></ul></ul></ul><ul><ul><ul><li>Esotropia more at near than distance </li></ul></ul></ul><ul><ul><li>Intermittent exotropia </li></ul></ul><ul><ul><ul><li>Extotropia manifests at certain point of time only </li></ul></ul></ul>
    7. 7. Optical therapy <ul><li>Amblyopia </li></ul><ul><ul><li>Reduction of vision in one or both eyes without with out obvious pathological cause and vision can’t be restored to normal by any optical, medical and surgical therapy </li></ul></ul><ul><li>Occupational optics </li></ul><ul><ul><li>Protect the eye from hazard or external environment </li></ul></ul>
    8. 8. Identify the anomalies
    9. 9. Optical therapy <ul><li>Method of correction </li></ul><ul><ul><li>Spectacle glass </li></ul></ul><ul><ul><li>Contact lenses </li></ul></ul><ul><ul><li>Laser refractive therapy </li></ul></ul>
    10. 10. Optical therapy <ul><li>Method of correction </li></ul><ul><ul><li>Intra corneal ring </li></ul></ul><ul><ul><li>Phakic IOL </li></ul></ul><ul><ul><li>Corneal refractive therapy </li></ul></ul>
    11. 11. What are they? <ul><li>Optical </li></ul><ul><li>Medical </li></ul><ul><li>Surgical </li></ul><ul><li>Laser </li></ul><ul><li>Cryotherapy </li></ul><ul><li>Vision therapy </li></ul>
    12. 12. Ocular pharmacotherapy <ul><li>four methods of delivery </li></ul><ul><ul><li>Topical instillation in to conjunctival sac </li></ul></ul><ul><ul><li>Periocular injection, </li></ul></ul><ul><ul><li>Intraocular injection </li></ul></ul><ul><ul><li>Systemic administration </li></ul></ul>
    13. 13. A. Topical instillation in to conjunctival sac <ul><li>Administered in the form of </li></ul><ul><li>Eye drops </li></ul><ul><ul><li>Specially day time use </li></ul></ul><ul><ul><li>Immediate action </li></ul></ul><ul><li>Ointments </li></ul><ul><ul><li>Increase bioavailability of the drug </li></ul></ul><ul><ul><li>Prevent dilution and quick absorption </li></ul></ul><ul><ul><li>Bed time use </li></ul></ul><ul><li>Gels </li></ul><ul><ul><li>Prolong contact time </li></ul></ul>
    14. 14. A. Topical instillation in to conjunctival sac <ul><li>Ocuserts </li></ul><ul><ul><li>Form of system of drug delivery through a membrane </li></ul></ul><ul><ul><li>Release drug in constant rate </li></ul></ul><ul><li>Soft contact lens </li></ul><ul><ul><li>Deliver high concentration of drug in emergency treatment </li></ul></ul>
    15. 15. B. Periocular injection <ul><li>Subconjunctival injection </li></ul><ul><ul><li>Use to achieve high concentration of drugs </li></ul></ul><ul><ul><li>Penetrate large sized molecules </li></ul></ul><ul><li>Subtenon injection </li></ul><ul><ul><li>Prefer over subconjunctival </li></ul></ul><ul><ul><li>Anterior subtenon is used to administer steroids </li></ul></ul><ul><ul><li>Posterior subtenons is used for intermediate and posterior uveitis </li></ul></ul>
    16. 16. B. Periocular injection <ul><li>Retrobulbar injection </li></ul><ul><ul><li>Deliver drug for optic neuritis, papillitis, retorbulbar block </li></ul></ul><ul><li>Peribulbar injection </li></ul><ul><ul><li>now a days a frequent use as anesthetic agents </li></ul></ul>
    17. 17. C. Intraocular injection <ul><li>Made in desperate cases </li></ul><ul><li>Intracameral injection (anterior chambers) </li></ul><ul><li>Intravtreal injection </li></ul>
    18. 18. D. Systemic administration <ul><li>Route </li></ul><ul><ul><li>Oral </li></ul></ul><ul><ul><li>Intramuscular </li></ul></ul><ul><ul><li>Intravenous </li></ul></ul><ul><li>Medicine should cross the blood aqueous barrier </li></ul><ul><ul><li>Low molecular weight and lipid soluble (sulphonamide) drugs readily penetrate the barrier </li></ul></ul>
    19. 19. What are they? <ul><li>Optical </li></ul><ul><li>Medical </li></ul><ul><li>Surgical </li></ul><ul><li>Laser </li></ul><ul><li>Cryotherapy </li></ul><ul><li>Vision therapy </li></ul>
    20. 20. Surgical therapy <ul><li>Surgery for lid </li></ul><ul><ul><li>Chalazion </li></ul></ul><ul><ul><ul><li>Chronic non-infective granulomatous inflammation of meibomian gland </li></ul></ul></ul><ul><ul><li>Ectropion </li></ul></ul><ul><ul><li>Entropion </li></ul></ul><ul><ul><li>Lagophthalmos </li></ul></ul><ul><ul><ul><li>Incomplete closure of eye lids </li></ul></ul></ul><ul><ul><li>Ptosis </li></ul></ul>Tarsoraphy done in Right eye
    21. 21. Surgical therapy <ul><li>Surgery of conjunctiva </li></ul><ul><ul><li>Pterygium </li></ul></ul><ul><ul><li>Conjuctival cysts </li></ul></ul><ul><ul><li>Conjunctival dermoid </li></ul></ul><ul><ul><li>symblepharon </li></ul></ul>
    22. 22. Surgical therapy <ul><li>Cornea </li></ul><ul><ul><li>Penetrating keratoplasty (PK) </li></ul></ul><ul><ul><li>Lamellar keratoplasty </li></ul></ul><ul><ul><li>Refractive surgery </li></ul></ul><ul><ul><ul><li>Laser in situ keratomileusis (LASIK) </li></ul></ul></ul><ul><li>Sclera </li></ul><ul><ul><li>Staphyloma </li></ul></ul><ul><ul><li>Scleral buckling </li></ul></ul>
    23. 23. Surgical therapy <ul><li>Surgery for Uvea </li></ul><ul><ul><li>Melanoma of choroid, iris and ciliary body </li></ul></ul><ul><ul><ul><li>A malignant tumour of melanocytes </li></ul></ul></ul><ul><ul><li>Hemangioma of choroid </li></ul></ul><ul><ul><ul><li>a malignant self-involuting tumour of endothelial cells, lining blood vessels </li></ul></ul></ul>
    24. 24. Surgical therapy <ul><li>Surgery for cataract </li></ul><ul><ul><li>Extra Capsular cataract extraction with posterior capsular intraocular lens implant (ECCE PC IOL) </li></ul></ul><ul><ul><li>Small incision cataract surgery (SICS) </li></ul></ul><ul><ul><li>Phacoemulsification (Phaco) </li></ul></ul><ul><ul><li>Surgical Aphakia </li></ul></ul><ul><ul><li>AC IOL </li></ul></ul>
    25. 25. Surgical therapy <ul><li>Surgery for glaucoma </li></ul><ul><ul><li>Goniotomy </li></ul></ul><ul><li>a surgical procedure in which a goniolens is used to see the structures of anterior chamber </li></ul><ul><li>An opening is made in the trabecular meshwork located in the drainage angle, where fluid leaves the eye. </li></ul><ul><li>The new opening provides a way for fluid to flow out of the eye. </li></ul><ul><li>Goniotomy is a surgery for congenital glaucoma only </li></ul>
    26. 26. Surgical therapy <ul><li>Surgery for glaucoma </li></ul><ul><ul><li>Trabeculotomy </li></ul></ul><ul><ul><ul><li>A surgical procedure in which a piece of tissue in the eye’s drainage angle is removed to create an opening. </li></ul></ul></ul><ul><ul><ul><li>This new opening allows fluid to drain out of the eye </li></ul></ul></ul><ul><ul><ul><li>Congenital glaucoma </li></ul></ul></ul>
    27. 27. Surgical therapy <ul><li>Surgery for glaucoma </li></ul><ul><ul><li>Peripheral iridectomy </li></ul></ul><ul><ul><ul><li>Treatment in ACG and prophylaxis in fellow eye </li></ul></ul></ul><ul><ul><ul><li>A procedure in which a small section of peripheral iris is excised through a limbal incision </li></ul></ul></ul><ul><ul><ul><li>Neodynium:YAG and/or argon laser </li></ul></ul></ul>
    28. 28. Surgical therapy <ul><li>Surgery for glaucoma </li></ul><ul><ul><li>Filtration surgery (trabeculectomy) </li></ul></ul><ul><ul><ul><li>Partial thickness filtering surgery in which a new channel is created around the margin of scleral flap through which aqueous flows from Anterior chamber into the subconjunctival space </li></ul></ul></ul>
    29. 29. Surgical therapy <ul><li>Surgery for vitreous </li></ul><ul><ul><li>Vitrectomy (vitreous hemorrhage, and vitreous opacity) </li></ul></ul><ul><ul><ul><li>Vitrectomy  is a surgery to remove some or all of the vitreous humor from the eye </li></ul></ul></ul>
    30. 30. Surgical therapy <ul><li>Surgery for retina </li></ul><ul><ul><li>Sealing of retinal break (high myopia) </li></ul></ul><ul><ul><ul><li>photocoagulation </li></ul></ul></ul><ul><ul><li>Scleral buckling </li></ul></ul><ul><ul><ul><li>Procedure that can be used to repair a retinal detachment </li></ul></ul></ul><ul><ul><ul><li>Thin silicone band is used </li></ul></ul></ul>
    31. 31. Surgical therapy <ul><li>Surgery for retina </li></ul><ul><ul><li>Pars plana vitrectomy </li></ul></ul><ul><ul><ul><li>Procedure to remove clouded vitreous with blood or vitreous opacities </li></ul></ul></ul>
    32. 32. Surgical therapy <ul><li>Strabismus and nystagmus </li></ul><ul><ul><li>Muscle weaking procedures (recession, myotomy) </li></ul></ul><ul><ul><li>Muscle strengthening procedure (resection) </li></ul></ul><ul><ul><li>Procedure that changes the direction </li></ul></ul><ul><li>Surgery for dacryocystitis </li></ul><ul><ul><li>Dacryocystorhinostomy </li></ul></ul>
    33. 33. What are they? <ul><li>Optical </li></ul><ul><li>Medical </li></ul><ul><li>Surgical </li></ul><ul><li>Laser </li></ul><ul><li>Cryotherapy </li></ul><ul><li>Vision therapy </li></ul>
    34. 34. Laser therapy <ul><li>Laser: light amplification by stimulated emission of radiation </li></ul><ul><li>a mechanism for emitting electromagnetic radiation, via the process of stimulated emission </li></ul><ul><li>Properties of laser </li></ul><ul><ul><li>Monochromatic </li></ul></ul><ul><ul><li>Coherent </li></ul></ul><ul><ul><li>Collimated </li></ul></ul><ul><ul><li>No scattering </li></ul></ul>
    35. 35. Production of laser beam Gas/Liquid filled chamber Opaque mirror Semi-transparent mirror +++++++++++++++++++++++ - - - - - - - - - - - - M M M M M M M Emission of laser Release the excessive energy in the form of light which is amplified to an appropriate wavelength
    36. 36. Lasers used in ophthalmology Photocoagulation Diode and Nd: YAG crystal Diode pumped Nd YAG Photoablation Helium and fluorine Excimer Photodisruption A liquid dry or a solid compound of Yt-Al garnet+neodymium, Nd: YAG Photocoagulation Diode crystal Diode Photocoagulation Krypton gas Krypton photocoagulation Argon gas Argon Effect produced Atomic environment Type
    37. 37. Lasers used in ophthalmology <ul><li>Definitions </li></ul><ul><li>Photocoagulation: The coagulation (clotting) of tissue using a laser which produces light in the visible green wavelength that is selectively absorbed by hemoglobin, in order to seal off bleeding blood vessels </li></ul><ul><li>Photoablation: volatilization of tissue by ultraviolet rays emitted by a laser for remodeling </li></ul><ul><li>Photodisruption: exert a cutting incision upon the tissue by laser application for breakage of layer of structure </li></ul>
    38. 38. Mechanism of laser effect and their therapeutic applications <ul><li>Photocoagulation: </li></ul>Absorption of laser light by tissues Conversion of Light to heat Raise temp of target tissue Denature and Coagulate cellular elements Treat ocular diseases by Production of scar, occlusion of vessels, tissue atrophy tissue contraction Application Peripheral iridectomy Argon laser trabeculoplasty Pan retinal photocoagulation Focal or grid retinal photocoagulation
    39. 39. Mechanism of laser effect and their therapeutic applications <ul><li>Photodisruption </li></ul>Ionize the electrons of target tissue Produce the physical State of momentarily expanding pressure Nd: YAG laser Exert a cutting/ incision effect upon the tissue Application Capsulotomy Membranectomy phacolysis
    40. 40. Mechanism of laser effect and their therapeutic applications <ul><li>Photoablation </li></ul>Exited dimer laser (Excimer laser) UV 192nm Break chemical bonds of biological materials Convert them into small molecules that diffuse away Tissue modeling Application PRK LASIK PTK
    41. 41. What are they? <ul><li>Optical </li></ul><ul><li>Medical </li></ul><ul><li>Surgical </li></ul><ul><li>Laser </li></ul><ul><li>Cryotherapy </li></ul><ul><li>Vision therapy </li></ul>
    42. 42. Cryotherapy in Ophthalmology <ul><li>Cryopexy means to produce tissue injury by application of intense cold (-40º to 100 ºC) </li></ul><ul><li>Cryounit uses freon, nitrous oxide or carbon dioxide gas as a cooling agent </li></ul><ul><li>Its goal is to decrease cellular metabolism, increase cellular survival, decrease inflammation, decrease pain and spasm, promote vasoconstriction, and when using extreme temperatures, to destroy cells by crystallizing the cytosol </li></ul>
    43. 43. Cryotherapy in Ophthalmology <ul><li>Mode of action </li></ul><ul><ul><li>Therapeutic effect by tissue necrosis (tumor) </li></ul></ul><ul><ul><li>Adhesion of tissues (seal retinal and choroidal detachment: cryopexy) </li></ul></ul><ul><ul><li>Cryolysis of trichiasis </li></ul></ul><ul><ul><li>Cryoextraction of lens </li></ul></ul>
    44. 44. What are they? <ul><li>Optical </li></ul><ul><li>Medical </li></ul><ul><li>Surgical </li></ul><ul><li>Laser </li></ul><ul><li>Cryotherapy </li></ul><ul><li>Vision therapy </li></ul>
    45. 45. Vision therapy <ul><li>VT is a treatment plan used to correct or improve specific dysfunctions of the vision system determined by standardized diagnostic criteria. </li></ul><ul><li>strabismus, amblyopia, disfunction in binocular vision, accommodation, ocular motor function and visual-perceptual-motor abilities, learning and reading disability </li></ul><ul><li>Treatment plans may encompass the use of lenses, prisms, occlusion and other appropriate materials, modalities and equipment. </li></ul>
    46. 46. Thank you