Theoretical fitting characteristics of typical soft contact lens designs

Contact Lens & Anterior Eye : the Journal of the British Contact Lens Association
Anna SulleyGraeme Young

Abstract

To calculate theoretical fitting success rates (SR) for a range of typical soft contact lens (SCL) designs using a mathematical model. A spreadsheet mathematical model was used to calculate fitting SR for various SCL designs. Designs were evaluated using ocular topography data from 163 subjects. The model calculated SR based on acceptable edge strain (within range 0-6%) and horizontal diameter overlap (range 0.2-1.2mm). Where lenses had multiple base curves (BCs), eyes unsuccessful with the steeper BC were tested with the flatter BC and aggregate SR calculated. Calculations were based on typical, current, hydrogel and silicone hydrogel SCLs and allowed for appropriate on-eye shrinkage (1.0-2.3%). Theoretical results were compared with those from actual clinical trials. Theoretical success rates for one-BC lenses ranged from 60.7% (95% CI 7.2%) to 90.2% (95% CI 3.7%). With two-BC designs, most combinations showed a SR increase with a second BC (84.0%-90.2%). However, one of the two-BC combinations showed only negligible increase with a second BC (72.4%-73.0%). For designs with lower SR, the greatest contributor to failure was inadequate lens diameter. For a given design, differences in shrinkage (i.e. on-eye bulk dehydration) ha...Continue Reading

References

May 1, 1982·American Journal of Optometry and Physiological Optics·D K Martin, B A Holden
Apr 1, 1981·American Journal of Optometry and Physiological Optics·E WakeR B Mandell
May 1, 1993·Optometry and Vision Science : Official Publication of the American Academy of Optometry·G YoungG Cooke
Apr 1, 1996·Optometry and Vision Science : Official Publication of the American Academy of Optometry·G Young
Jun 1, 2001·International Contact Lens Clinic : ICLC·N PritchardD Brazeau
Jan 1, 1997·Contact Lens & Anterior Eye : the Journal of the British Contact Lens Association·G YoungS Watson
Sep 15, 2010·Optometry and Vision Science : Official Publication of the American Academy of Optometry·Jerome OzkanBrien Holden
Sep 10, 2011·Eye & Contact Lens·Graeme YoungOliver Harmer
Dec 29, 2012·Eye & Contact Lens·Meng C Lin, Thao N Yeh
Feb 12, 2013·Contact Lens & Anterior Eye : the Journal of the British Contact Lens Association·Jerome OzkanPercy Lazon de la Jara
Apr 4, 2013·Investigative Ophthalmology & Visual Science·Lee A HallJames Wolffsohn
Sep 24, 2013·Investigative Ophthalmology & Visual Science·Lyndon JonesUNKNOWN members of the TFOS International Workshop on Contact Lens Discomfort
Jun 6, 2014·Optometry and Vision Science : Official Publication of the American Academy of Optometry·Graeme Young
Oct 30, 2015·Eye & Contact Lens·Graeme YoungAnna Sulley
Jan 19, 2017·Optometry and Vision Science : Official Publication of the American Academy of Optometry·Graeme YoungJames S Wolffsohn

❮ Previous
Next ❯

Citations

May 16, 2019·PloS One·Ahmed AbassAhmed Elsheikh
Jan 12, 2021·Contact Lens & Anterior Eye : the Journal of the British Contact Lens Association·Eef van der WorpPatrick Caroline
Apr 12, 2020·Contact Lens & Anterior Eye : the Journal of the British Contact Lens Association·Eef van der WorpLyndon Jones
Mar 30, 2021·Contact Lens & Anterior Eye : the Journal of the British Contact Lens Association·Fiona StapletonJames S Wolffsohn
Mar 30, 2021·Contact Lens & Anterior Eye : the Journal of the British Contact Lens Association·James S WolffsohnFiona Stapleton

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.

Related Papers

Optometry and Vision Science : Official Publication of the American Academy of Optometry
Graeme YoungJames S Wolffsohn
Optometry and Vision Science : Official Publication of the American Academy of Optometry
Graeme Young
Optometry and Vision Science : Official Publication of the American Academy of Optometry
S Patel
Optometry and Vision Science : Official Publication of the American Academy of Optometry
D Lieberman
© 2022 Meta ULC. All rights reserved