Hydrogels Applications in Opthamology 2102022 1 Polyelectrolyte Hydrogels

Hydrogels / Applications in Opthamology 2/10/2022 1

Polyelectrolyte Hydrogels Hydrophilic polymer chains containing positive or negatively charged functional groups that interact electrostatic interactions to form a cross-linked network that attracts water 2/10/2022 2

Hylauronic Acid 2/10/2022 3

Polyelectrolyte Multilayers Layer by layer deposition 2/10/2022 4

Alginate gels 2/10/2022 5

Enzyme Immobilization 2/10/2022 6

Cell Encapsulation 2/10/2022 7

Alginate gels 2/10/2022 8

2/10/2022 9

2/10/2022 10

Alginate gels 2/10/2022 11

Applications l l l l artificial tendon and cartilage wound healing dressings (Vigilon®, Hydron®, Gelperm®) l non-antigenic, flexible wound cover l permeable to water and metabolites l low-strength artificial kidney membranes artificial skin maxillofacial and sexual organ reconstruction materials vocal cord replacement 2/10/2022 12

Corning® Ultra Low Attachment Products Unique hydrogel surface inhibits cell attachment 2/10/2022 13

Hydrogels: Applications Earliest biomedical application contact lenses l good mechanical stability l favorable refractive index l high oxygen permeability l needs hygienic maintenance l unable to correct for astigmatism 2/10/2022 14

Acrylates 2/10/2022 15

Methacrylates 2/10/2022 16

Poly(methyl methacrylate) 2/10/2022 17

2/10/2022 18

2/10/2022 19

Poly(2 -hydroxyethylmethacrylate p. HEMA 2/10/2022 20

Hydrogels: PHEMA l l l l The most widely used hydrogel water content similar to living tissues inert to biological processes shows resistance to degradation permeable to metabolites not absorbed by the body withstands sterilization by heat prepared in various shaped and forms 2/10/2022 21

Contact lens l l l PMMA HEMA Fabrication methods l Computer assisted cutting (lathe)-PMMA rods l Spin casting-polymerization l Molding-polymerization 2/10/2022 22

2/10/2022 23

2/10/2022 24

Intraocular lens l l l PMMA HEMA Polymer backbone - mixture of PMMA and PHEMA Varying water contents Additives such as UV blockers 2/10/2022 25

2/10/2022 26

2/10/2022 27

2/10/2022 28

2/10/2022 29

2/10/2022 30

2/10/2022 31

2/10/2022 32

Foldable IOL complications/explantations - 2/10/2022 33

Reasons for Revision Surgery l l Incorrect lens power seen most commonly Glare/optical aberrations Dislocation/decentration Late postoperative opacification 2/10/2022 34

IOL Optic Opacification l l l Surface opacification Opacification within the substance of the optic Analysis of opacifications reveals presence of calcium Calcium staining Scanning electron microscopic analysis 2/10/2022 35

2/10/2022 36

2/10/2022 37

2/10/2022 38

2/10/2022 39

2/10/2022 40

2/10/2022 41

2/10/2022 42

Accommodative IOL: 1 CU (Human. Optics) Total diameter: 9. 7 mm 2/10/2022 43