SlideShare a Scribd company logo
Viscoelastics in ophthalmicsurgery OphthalmicViscosurgicalDevices – OVD DusanPusnik Novo mesto, Slovenia
Viscoelastics To protecttheoculartissue – mechanicalandlessdevelopmentoffreeradicalsduringphacoemulsification-Takahashi, Maugeryresearch To manipulatethetissue To maintainthespaceduringsurgery
OVD- Characteristics Viscosity – measurementofhowmuchenergy it takes to deformthe OVD Shear - forcethatoccurswhenobjectpassesviscoelastic substance Pseudoplastic – differencebetweenrestinganddynamicviscosity Elasticity – tendency to return to original shapeafterbeingstretched Coatability – adhesivness
Viscosity Viscosity – measurementofhowmuchenergy it takes to deformthe OVD Restingviscosity – measurementofresistance to flowwhen substance is at rest Dynamicviscosity – measurementofresistance to flowwhen substance is underpressure (shear) Thegreaterthedifferencethe more PSEUDOPLASTIC the material is
Viscoelastics – polymerstructure Hydroxipropylmethylcellulose (HPMC) Hyluronicacid (NaHa) Chondroitine sulfate (CS)
Hydroxypropylmethylcellulose Plantorigin – cellulose Lowmolecularweight Lowcost Methylvisc, Ocucoat, Viscel,…
Hyaluronicacid (NaHa) Polysaccharide (sugar) naturallypresent in the human bodyandeyes Totallybiocompatible, biodegradable MolecularweightthatcanattainmillionsofDaltons Twooriginsofsodiumhyaluronate (NaHa) Non-animal = biofermatation-bacterialfermantationAmvisc, Provisc Animal (extractionofroostercombs), Healon, Hyalmax, Hyalvisc,…
Chondroitine sulfate (CS) Polysaccharidealsopresent in the human body Biocompatibleandbiodegradable Veryhighcoveringpower Lowmolecularweightcompared to longNaHachain Riskofallergy (animalorigin) Viscoat
Requirementsofviscoelastics Perfectly transparent Easy to injectandremove Sterile Noninflammatory Nonallergenic Pyrogenfree
Cohesiveviscoelastic Highmolecularweight Pseudoplastic Long molecularchain Goodformaintainingspace Easy to remove Veryhigh rise ofocularpressureif not totallywashedout (more than 60mmHg)-verydangerous Healon, Provisc, healov GV, Amvisc
Dispersiveviscoelastic Tendencyofthe OVD to spread Shortmolecularchain Goodcoatability Goodtissueprotection More difficult to remove Not veryhigh rise ofocularpressureif not totallywashedout (30-40 mmHg) Viscoat, Occucoat, Celoftal, Cellugel, Viscel,…
Cohesiveanddispersive No  OVD – OcularViscoelastic Device is ideal Mixeduseof OVD Duovisc Rhexeal Achievesthebenefitsandeliminatesthedisadvantagesofeachtypeof OVD
Viscoelasticcomplications IOP elevationdue to incompleteremovalofviscoelastics Woundburns, whenOVDs (Healon 5) blockthespaceforirrigatingfluidduringphacoemulsification
Conclusion Totalwashingoutofthe OVD is mandatoryespeciallyforcohesiveviscoelastics (more than 60mmHg rise ofocularpressure Use differenttechniquesforremoving Washoutunderthelens as well No ideal OVD Take yourown OVD, suitableforyoursurgerytechniqueand skills
Thankyou DusanPusnik Novo mesto Slovenia

More Related Content

What's hot

Ocular inserts
Ocular insertsOcular inserts
Ocular inserts
amina tariq
 
Pharmaceutical Engineering: Crystallization
Pharmaceutical Engineering: Crystallization Pharmaceutical Engineering: Crystallization
Pharmaceutical Engineering: Crystallization
Parag Jain
 
Caking of crystals
Caking of crystalsCaking of crystals
Caking of crystals
aashish garg
 
The material of smc manhole cover / Batch test
The material of smc manhole cover / Batch testThe material of smc manhole cover / Batch test
The material of smc manhole cover / Batch test
sammy elesh
 
EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...
EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...
EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...
EWMAConference
 
Crystallization process chemistry
Crystallization process chemistryCrystallization process chemistry
Crystallization process chemistry
yesimin
 
Crystallization
Crystallization Crystallization
Crystallization
vicky vicky
 

What's hot (7)

Ocular inserts
Ocular insertsOcular inserts
Ocular inserts
 
Pharmaceutical Engineering: Crystallization
Pharmaceutical Engineering: Crystallization Pharmaceutical Engineering: Crystallization
Pharmaceutical Engineering: Crystallization
 
Caking of crystals
Caking of crystalsCaking of crystals
Caking of crystals
 
The material of smc manhole cover / Batch test
The material of smc manhole cover / Batch testThe material of smc manhole cover / Batch test
The material of smc manhole cover / Batch test
 
EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...
EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...
EWMA 2013 - Ep558 - USE OF A NEW HYDRO-DESLOUGHING ABSORBENT DRESSING* IN A N...
 
Crystallization process chemistry
Crystallization process chemistryCrystallization process chemistry
Crystallization process chemistry
 
Crystallization
Crystallization Crystallization
Crystallization
 

Viewers also liked

OCULAR VISCO ELASTICS
OCULAR VISCO ELASTICSOCULAR VISCO ELASTICS
OCULAR VISCO ELASTICS
SSSIHMS-PG
 
OVD RESULTS IN PHACO
OVD RESULTS IN PHACOOVD RESULTS IN PHACO
OVD RESULTS IN PHACO
fernando aguilera
 
Ophthalmic Manifestations of Hematological Malignancies
Ophthalmic Manifestations of Hematological MalignanciesOphthalmic Manifestations of Hematological Malignancies
Ophthalmic Manifestations of Hematological Malignancies
Paavan Kalra
 
Disorders of hypoigmentation cont.
Disorders of hypoigmentation cont.Disorders of hypoigmentation cont.
Disorders of hypoigmentation cont.
Ibrahim Farag
 
26 ectopia lentis
26 ectopia lentis26 ectopia lentis
26 ectopia lentis
Mohamad Jeffrey Ismail
 
Electro oculography
Electro oculographyElectro oculography
Electro oculography
Praneeth Kumar
 
Vascular Lesions Of The Orbit
Vascular Lesions Of The OrbitVascular Lesions Of The Orbit
Vascular Lesions Of The Orbit
Xiu Srithammasit
 
Phakomatoses(Ophthalmology)
Phakomatoses(Ophthalmology)Phakomatoses(Ophthalmology)
Phakomatoses(Ophthalmology)
Shylesh Dabke
 
Ectopia lentis edit
Ectopia lentis editEctopia lentis edit
Ectopia lentis edit
Laxmi Eye Institute
 
Pearls of ophthalmology
Pearls of ophthalmologyPearls of ophthalmology
Pearls of ophthalmology
Abdul Wasay Baloch
 
Irrigation in endo ppt
 Irrigation in endo ppt Irrigation in endo ppt
Irrigation in endo ppt
Daniel Baiyee
 
Most common opthalmology slides with anwers in uhs ospe
Most common opthalmology slides with anwers in uhs ospeMost common opthalmology slides with anwers in uhs ospe
Most common opthalmology slides with anwers in uhs ospe
Verdah Sabih
 
Iridocorneal endothelial syndrome
Iridocorneal endothelial syndromeIridocorneal endothelial syndrome
Iridocorneal endothelial syndrome
SSSIHMS-PG
 
Age-Related Macular Degeneration
Age-Related Macular DegenerationAge-Related Macular Degeneration
Age-Related Macular Degeneration
Hossein Mirzaie
 
RED EYE
RED EYERED EYE

Viewers also liked (15)

OCULAR VISCO ELASTICS
OCULAR VISCO ELASTICSOCULAR VISCO ELASTICS
OCULAR VISCO ELASTICS
 
OVD RESULTS IN PHACO
OVD RESULTS IN PHACOOVD RESULTS IN PHACO
OVD RESULTS IN PHACO
 
Ophthalmic Manifestations of Hematological Malignancies
Ophthalmic Manifestations of Hematological MalignanciesOphthalmic Manifestations of Hematological Malignancies
Ophthalmic Manifestations of Hematological Malignancies
 
Disorders of hypoigmentation cont.
Disorders of hypoigmentation cont.Disorders of hypoigmentation cont.
Disorders of hypoigmentation cont.
 
26 ectopia lentis
26 ectopia lentis26 ectopia lentis
26 ectopia lentis
 
Electro oculography
Electro oculographyElectro oculography
Electro oculography
 
Vascular Lesions Of The Orbit
Vascular Lesions Of The OrbitVascular Lesions Of The Orbit
Vascular Lesions Of The Orbit
 
Phakomatoses(Ophthalmology)
Phakomatoses(Ophthalmology)Phakomatoses(Ophthalmology)
Phakomatoses(Ophthalmology)
 
Ectopia lentis edit
Ectopia lentis editEctopia lentis edit
Ectopia lentis edit
 
Pearls of ophthalmology
Pearls of ophthalmologyPearls of ophthalmology
Pearls of ophthalmology
 
Irrigation in endo ppt
 Irrigation in endo ppt Irrigation in endo ppt
Irrigation in endo ppt
 
Most common opthalmology slides with anwers in uhs ospe
Most common opthalmology slides with anwers in uhs ospeMost common opthalmology slides with anwers in uhs ospe
Most common opthalmology slides with anwers in uhs ospe
 
Iridocorneal endothelial syndrome
Iridocorneal endothelial syndromeIridocorneal endothelial syndrome
Iridocorneal endothelial syndrome
 
Age-Related Macular Degeneration
Age-Related Macular DegenerationAge-Related Macular Degeneration
Age-Related Macular Degeneration
 
RED EYE
RED EYERED EYE
RED EYE
 

Recently uploaded

BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
Nguyen Thanh Tu Collection
 
Electric Fetus - Record Store Scavenger Hunt
Electric Fetus - Record Store Scavenger HuntElectric Fetus - Record Store Scavenger Hunt
Electric Fetus - Record Store Scavenger Hunt
RamseyBerglund
 
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...
TechSoup
 
The basics of sentences session 7pptx.pptx
The basics of sentences session 7pptx.pptxThe basics of sentences session 7pptx.pptx
The basics of sentences session 7pptx.pptx
heathfieldcps1
 
C1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptx
C1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptxC1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptx
C1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptx
mulvey2
 
Benner "Expanding Pathways to Publishing Careers"
Benner "Expanding Pathways to Publishing Careers"Benner "Expanding Pathways to Publishing Careers"
Benner "Expanding Pathways to Publishing Careers"
National Information Standards Organization (NISO)
 
Standardized tool for Intelligence test.
Standardized tool for Intelligence test.Standardized tool for Intelligence test.
Standardized tool for Intelligence test.
deepaannamalai16
 
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptxNEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
iammrhaywood
 
Chapter wise All Notes of First year Basic Civil Engineering.pptx
Chapter wise All Notes of First year Basic Civil Engineering.pptxChapter wise All Notes of First year Basic Civil Engineering.pptx
Chapter wise All Notes of First year Basic Civil Engineering.pptx
Denish Jangid
 
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
Nguyen Thanh Tu Collection
 
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
GeorgeMilliken2
 
Temple of Asclepius in Thrace. Excavation results
Temple of Asclepius in Thrace. Excavation resultsTemple of Asclepius in Thrace. Excavation results
Temple of Asclepius in Thrace. Excavation results
Krassimira Luka
 
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skillsspot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
haiqairshad
 
skeleton System.pdf (skeleton system wow)
skeleton System.pdf (skeleton system wow)skeleton System.pdf (skeleton system wow)
skeleton System.pdf (skeleton system wow)
Mohammad Al-Dhahabi
 
Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...
PsychoTech Services
 
Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"
Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"
Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"
National Information Standards Organization (NISO)
 
Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47
MysoreMuleSoftMeetup
 
MDP on air pollution of class 8 year 2024-2025
MDP on air pollution of class 8 year 2024-2025MDP on air pollution of class 8 year 2024-2025
MDP on air pollution of class 8 year 2024-2025
khuleseema60
 
Présentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptx
Présentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptxPrésentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptx
Présentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptx
siemaillard
 
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
PECB
 

Recently uploaded (20)

BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
 
Electric Fetus - Record Store Scavenger Hunt
Electric Fetus - Record Store Scavenger HuntElectric Fetus - Record Store Scavenger Hunt
Electric Fetus - Record Store Scavenger Hunt
 
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...
 
The basics of sentences session 7pptx.pptx
The basics of sentences session 7pptx.pptxThe basics of sentences session 7pptx.pptx
The basics of sentences session 7pptx.pptx
 
C1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptx
C1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptxC1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptx
C1 Rubenstein AP HuG xxxxxxxxxxxxxx.pptx
 
Benner "Expanding Pathways to Publishing Careers"
Benner "Expanding Pathways to Publishing Careers"Benner "Expanding Pathways to Publishing Careers"
Benner "Expanding Pathways to Publishing Careers"
 
Standardized tool for Intelligence test.
Standardized tool for Intelligence test.Standardized tool for Intelligence test.
Standardized tool for Intelligence test.
 
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptxNEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
 
Chapter wise All Notes of First year Basic Civil Engineering.pptx
Chapter wise All Notes of First year Basic Civil Engineering.pptxChapter wise All Notes of First year Basic Civil Engineering.pptx
Chapter wise All Notes of First year Basic Civil Engineering.pptx
 
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
 
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
 
Temple of Asclepius in Thrace. Excavation results
Temple of Asclepius in Thrace. Excavation resultsTemple of Asclepius in Thrace. Excavation results
Temple of Asclepius in Thrace. Excavation results
 
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skillsspot a liar (Haiqa 146).pptx Technical writhing and presentation skills
spot a liar (Haiqa 146).pptx Technical writhing and presentation skills
 
skeleton System.pdf (skeleton system wow)
skeleton System.pdf (skeleton system wow)skeleton System.pdf (skeleton system wow)
skeleton System.pdf (skeleton system wow)
 
Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...Gender and Mental Health - Counselling and Family Therapy Applications and In...
Gender and Mental Health - Counselling and Family Therapy Applications and In...
 
Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"
Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"
Jemison, MacLaughlin, and Majumder "Broadening Pathways for Editors and Authors"
 
Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47Mule event processing models | MuleSoft Mysore Meetup #47
Mule event processing models | MuleSoft Mysore Meetup #47
 
MDP on air pollution of class 8 year 2024-2025
MDP on air pollution of class 8 year 2024-2025MDP on air pollution of class 8 year 2024-2025
MDP on air pollution of class 8 year 2024-2025
 
Présentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptx
Présentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptxPrésentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptx
Présentationvvvvvvvvvvvvvvvvvvvvvvvvvvvv2.pptx
 
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
 

Viscoelastiques

  • 1. Viscoelastics in ophthalmicsurgery OphthalmicViscosurgicalDevices – OVD DusanPusnik Novo mesto, Slovenia
  • 2. Viscoelastics To protecttheoculartissue – mechanicalandlessdevelopmentoffreeradicalsduringphacoemulsification-Takahashi, Maugeryresearch To manipulatethetissue To maintainthespaceduringsurgery
  • 3. OVD- Characteristics Viscosity – measurementofhowmuchenergy it takes to deformthe OVD Shear - forcethatoccurswhenobjectpassesviscoelastic substance Pseudoplastic – differencebetweenrestinganddynamicviscosity Elasticity – tendency to return to original shapeafterbeingstretched Coatability – adhesivness
  • 4. Viscosity Viscosity – measurementofhowmuchenergy it takes to deformthe OVD Restingviscosity – measurementofresistance to flowwhen substance is at rest Dynamicviscosity – measurementofresistance to flowwhen substance is underpressure (shear) Thegreaterthedifferencethe more PSEUDOPLASTIC the material is
  • 5. Viscoelastics – polymerstructure Hydroxipropylmethylcellulose (HPMC) Hyluronicacid (NaHa) Chondroitine sulfate (CS)
  • 6. Hydroxypropylmethylcellulose Plantorigin – cellulose Lowmolecularweight Lowcost Methylvisc, Ocucoat, Viscel,…
  • 7. Hyaluronicacid (NaHa) Polysaccharide (sugar) naturallypresent in the human bodyandeyes Totallybiocompatible, biodegradable MolecularweightthatcanattainmillionsofDaltons Twooriginsofsodiumhyaluronate (NaHa) Non-animal = biofermatation-bacterialfermantationAmvisc, Provisc Animal (extractionofroostercombs), Healon, Hyalmax, Hyalvisc,…
  • 8. Chondroitine sulfate (CS) Polysaccharidealsopresent in the human body Biocompatibleandbiodegradable Veryhighcoveringpower Lowmolecularweightcompared to longNaHachain Riskofallergy (animalorigin) Viscoat
  • 9. Requirementsofviscoelastics Perfectly transparent Easy to injectandremove Sterile Noninflammatory Nonallergenic Pyrogenfree
  • 10. Cohesiveviscoelastic Highmolecularweight Pseudoplastic Long molecularchain Goodformaintainingspace Easy to remove Veryhigh rise ofocularpressureif not totallywashedout (more than 60mmHg)-verydangerous Healon, Provisc, healov GV, Amvisc
  • 11. Dispersiveviscoelastic Tendencyofthe OVD to spread Shortmolecularchain Goodcoatability Goodtissueprotection More difficult to remove Not veryhigh rise ofocularpressureif not totallywashedout (30-40 mmHg) Viscoat, Occucoat, Celoftal, Cellugel, Viscel,…
  • 12. Cohesiveanddispersive No OVD – OcularViscoelastic Device is ideal Mixeduseof OVD Duovisc Rhexeal Achievesthebenefitsandeliminatesthedisadvantagesofeachtypeof OVD
  • 13. Viscoelasticcomplications IOP elevationdue to incompleteremovalofviscoelastics Woundburns, whenOVDs (Healon 5) blockthespaceforirrigatingfluidduringphacoemulsification
  • 14. Conclusion Totalwashingoutofthe OVD is mandatoryespeciallyforcohesiveviscoelastics (more than 60mmHg rise ofocularpressure Use differenttechniquesforremoving Washoutunderthelens as well No ideal OVD Take yourown OVD, suitableforyoursurgerytechniqueand skills
  • 15. Thankyou DusanPusnik Novo mesto Slovenia