This document discusses presbyopic contact lenses and their history, principles, types, designs, fitting considerations, and tips for success. It provides an overview of bifocal contact lens options including simultaneous vision, alternating vision, monovision, multifocal, and non-refractive designs. Key aspects of the fitting process like determining the ideal candidate, measuring important parameters, and troubleshooting vision outcomes are summarized.
It contains Examination Protocol for Contact Lenses along with information about pre-requisites for fitting a Contact Lens. A helpful guide for all Students, Eye Care Practitioners (Optometrist, Ophthalmologist).
It contains Examination Protocol for Contact Lenses along with information about pre-requisites for fitting a Contact Lens. A helpful guide for all Students, Eye Care Practitioners (Optometrist, Ophthalmologist).
Contact lens for congenital aphakia and other eye conditions for infants and toddlers. The slide presentation encompasses indications for CL fitting in paediatric, contact lens options, fitting techniques, challenges and contact lens as myopia control.
Scleral lens is a large rigid contact lens with a diameter range of 15mm to 25mm. Its resting point is beyond the
corneal borders, and are believed to be among the best vision correction options for irregular corneas. Wearing scleral lens also can postpone or even prevent surgical intervention as well as decrease the risk of corneal scarring.
This presentation include what are the pre-assessment required for fitting Contact lens in children and process of insertion and removal with a small knowledge about different lens that we can use for pediatric Contact lens
Contact lens for congenital aphakia and other eye conditions for infants and toddlers. The slide presentation encompasses indications for CL fitting in paediatric, contact lens options, fitting techniques, challenges and contact lens as myopia control.
Scleral lens is a large rigid contact lens with a diameter range of 15mm to 25mm. Its resting point is beyond the
corneal borders, and are believed to be among the best vision correction options for irregular corneas. Wearing scleral lens also can postpone or even prevent surgical intervention as well as decrease the risk of corneal scarring.
This presentation include what are the pre-assessment required for fitting Contact lens in children and process of insertion and removal with a small knowledge about different lens that we can use for pediatric Contact lens
Troubleshooting bifocals and Market Availability in Nepal
Bifocals in Anisometropia
Prismatic Effect in Bifocal
Bifocal Prescription
Bifocals in High Astigmatism
Magnification is a method of increasing the size of the image
so that enough of the retina is stimulated to send an impulse
through the optic nerve allowing an object to be perceived .
250+ High Frequency MCQs in Optometry and OphthalmologyRabindraAdhikary
The collection of high-ranked, top-rated high frequency multiple-choice questions suitable for any examination of optometry, ophthalmology and ophthalmic sciences with their answers for FREE. No Log in, No Pay!!
Contact lens care and maintenance
RGP care
Soft Contact lens care
Silicon Hydrogel Care
Contact Lens Disinfection
Thermal disinfection
Chemical Disinfection
Oxidative chemical disinfection
Variables: Types and their Operational Definitions
Unit III: Problem identification formulation of research objectives and hypothesis (as part of M.Optom Curriculum of Pokhara University, Nepal)
Cholinergic agent: Autonomic Drugs
According to the M. Optom curriculum, we have prepared a concise presentation on Cholinergic or parasympathomimetic or cholinomimetic drugs
Multiple Choice Questions (MCQs) for Masters of Optometry Entrance Examinatio...RabindraAdhikary
Multiple Choice Questions (MCQs) for Masters of Optometry Entrance Examination, Pokhara University NEPAL
MCQs Optometry Nepal
Here we have included syllabus of entrance examinations for Master of Optometry in Pokhara University, entry requirements of candidate for the master of optometry course and multiple choice questions that appeared in the entrance examinations of 2019.
Prepared by: Rabindra Adhikary
for more MCQs:
http://ravinems.blogspot.com/2019/05/multiple-choice-questions-mcqs-for.html
Visual Implication in Diabetes Mellitus
These slides talk in detail about the visual implications of Diabetes Mellitus and how to address them systematically
Systemic Diseases and the Eye
Various systemic diseases affect the eye and it's functioning. Here we present those common systemic diseases that are responsible to cause effects in the eye.
What are the diseases that affect eye?
Eye is affected by the following diseases:
Systemic Hypertension (Increased blood pressure of the body)
Diabetes Melitus (Increased blood sugar level)
Systemic Lupus Erythromatosus (SLE)
AIDS and other Venereal Diseases like Syphilis
Sickle Cell Anemia,
Eales Disease and many more.
Look at the slides.
Ophthalmic Prisms: Prismatic Effects and DecentrationRabindraAdhikary
Ophthalmic Prisms: Prismatic Effects and Decentration
here we discuss about the ophthalmic prisms, the prismatic effects as caused by the decentration( moving the optical center away from the visual axis)
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
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New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
2. History
Feeinbloom, 1938
First reference to bifocal (scleral CL) (New York)
Williamson Noble (1951)
Bifocal CL with small convex central near portion on the front
surface
Freeman 1953
Pinhole lenses for presbyopic correction
De Carle 1957
Concentric bifocal with distance portion in the center (small) for
“Simultaneous Vision” .
Wesley & Jessen 1957-58
Concentric Bifocal with distance portion in the Center (larger)
Jessen 1958
1st
multifocal CL later named as aspheric bifocal CL in 1961
4. Why presbyopic contact
lenses??
Bifocal spectacles/reading glasses
Head tilting to see near
Restricted field of view
Outward symbol of aging
Switching glasses for reading
Distorted optics of progressive bifocals
Weight of spectacles
Magnification
Image jump
5. Indication for Bifocal CLs
Favourable
Eyelids in normal position
Average or smaller than average pupil size
Motivated Patient
Unfavourable
Abnormal eyelid position (Very high/low)
High lid laxity
Large pupil
Binocular imbalance
Residual astigmatism
High degree of corneal astigmatism
Narrow palpebral fissure
6. Ideal Candidate Guidelines
Lifestyles
Occupational requirements
Cosmetic appearance
Hobbies and interests
Avoid “Perfect” vision tasks
Physiological
-6.00D and +4.00D
prescription (vertex
adjusted)
Refractive ADDs up to
+2.50D
Cylinder correction of -0.75D
or less
Acceptable corneal health
7. Contact Lens Options
1. CL for distances & Single vision Spectacles for near
2. Monovision –
Single vision lenses correcting one for distance & one for near
1. Modified Monovision
Combination of single vision and multifocal CL
1. Bifocal or multifocal CL
Simultaneous vision or Bivision
Translating or Alternating Vision
Multizone bifocals (Aspheric)
1. Non-refractive bifocals
Multiple Pinhole lenses
Spherical aberration correcting lenses
Concentric aspheric’ multifocal lenses’
Diffractive lenses
8. Principle of Fitting Bifocal CLs
Two Principle
Simultaneous Vision
Alternate Vision
9. Simultaneous or Bivision bifocals
Bifocal lenses in the both eyes
Can use unequal adds
Use only the amount of add needed
Blurred image superimpose in either cases
distance or near focus
Depends on entrance of light and pupil size
The size of central distance portion should be
of 2.25 mm to 3.00 mm.
10.
11. Modified bivision
Bifocal lens in both eyes.
Over plus one eye at distance
to increase effective add &
to improve intermediate vision
12. Alternating vision bifocals
These bifocals provide alternating
vision
Distance portion for distance vision
Lens should move upward while near
work for near vision
A prism ballast of 1.5 pd base down is
placed to orient the lenses and
sometimes truncated.
13. Translating Bifocal CL Design
The near prescription
is on the bottom.
Truncated to avoid
lens rotation with
14. Monovision
The most common contact lens treatment for
presbyopia
uses a single vision contact lens in each eye or, a
lens in only one eye.
The dominant eye is generally corrected for
distance viewing;
the fellow eye, for near.
Modest decreases in contrast sensitivity &
stereopsis occur
affect the patient's driving & on-the-job performance.
15. Monovision
Even a mild loss of stereopsis and
report spatial disorientation
Patients report difficulty performing critical
distance vision tasks.
The reported rates of success range
from 60 to 80 percent.
17. Multizone bifocals
Concentric rings alternately powered for
distance & near adjacent zones interfaced
continuously ; no steps
Large number of distance and near reading
portions, pupil size maintain 50:50 comfort
Easy to fit – concerned on correct near
addition, good centration & minimal
movement.
18. 8 mm optic zone
Distance
-3.00 -
-2.00 -
-1.00 -
1 2 3 40
Power
mm from center
Power -3.00 / +2.00D
ACUVUE BifocalACUVUE Bifocal power changepower change
Near
20. Non-refractive Bifocals
Acts both for distance and near with
either no corrective power in the lens or
only a single vision prescription.
Pin Hole lenses – only used for academic
purpose
Spherical aberration correcting lens – a
front aspheric surface help to improve presbyopia
and astigmatism. Useful up to +1.50D.
Concentric aspheric ‘multifocal lenses’
21. Non-refractive Bifocals
Diffractive bifocals
Diffraction cause change in the power.
e. g. +2.00D (Blue) +3.50D (red)
But chromatic aberration of the eye
neutralizes it.
No longer available- Diffrax RGP lens
22. Bifocal choices
Good distance vision (flying, driving)
Avoid concentric lenses with small distance
portion in the center
Prefer for aspheric lenses / prism ballasted
lenses
Very good near vision (copy editor)
Rigid concentric lenses with small distance
portion in the center & use of prism ballast
23. Bifocal choices
Good intermediate vision below eye level
(word processor operator, musician)
Aspheric bifocal
Lens with addition used in dominant eye for
distance & non-dominant for near.
Good intermediate vision above eye level
(chemist)
Concentric lenses with addition for intermediate
focus in dominant eye.
Aspheric lenses to both eyes
24. Bifocal choices
Good intermediate vision above eye level
(librarian)
Concentric bifocal with peripheral near portion
Aspheric lenses to both eyes
Lenses required for social reasons
Monovision or aspheric lenses in both eyes
Concentric bifocal or
Two different powered lenses one in each eye for
intermediate and near vision
25. Measurements
Much important measurement:
Pupil diameter
Position and tightness of lower lid
Near addition
Size & shape of segment
Height of segment above the lower edge of the lens
Amount of prism ballast and thickness of lower
edge
Vertical total diameter
Stabilization
26. Bifocal Candidates
Good bifocal contact lens candidates
Average visual demands
Realistic expectations
Distance & near correction
Motivated
Normal tear & lid function
Poor bifocal contact lens candidates
No distance correction
Not motivated
Happy with Monovision
Abnormal tear & lid function
27. Rigid Bifocal- alternating
vision
Useful for significant corneal astigmatism
Need for high adds
Useful for critical near work
Designs:
Executive
Crescent
Fused segment
Problem – loose / tight lids
Need lower lid at inferior limbus
29. Aspheric soft bifocal lenses
Center near aspheric bifocal soft lens
Maximum plus power centrally
Progressive power effect
Good for early presbyopes
Need good centration
Center distance aspheric bifocal soft lens
Maximum plus peripherally
Provide good distance acuity
Limited add
Need larger pupils
30. Aspheric Bifocal CL Design
The near and distance
prescriptions are both
near the pupil
31. Concentric soft bifocal CL
Concentric center near bifocal soft CL
Pupil size is critical
Available in different add zones
Use different add zone for each eye if needed
Centration critical
Higher adds available
Concentric center distance bifocal soft CL
Less frequently used
Two rings
Centration critical
33. Others
Diffractive
Full pupil design
Multi-zone
Multiple alternating rings of correction
Good distance vision especially with lower
adds
Blending of zones improves intermediate
vision & reduces glare
34. Key to success
Practitioner should have good and
perfect knowledge
Detail eye examination is must
Patient should be properly explained
about adaptation period, cleaning
regiments and duration of the lens
35. Bifocal fitting tips
Let the lens settle first
Use loose trial lenses to over-refract
contact lens
Check vision binocularly
Avoid checking vision in a dark room
Push plus
Consider unequal adds
36. Success Steps for Fitting Bifocal
Manage patient expectations for
adaptation required for all Presbyopia
correction options.
Perform current Spectacle refraction with
binocular balanced prescription
Check Dominant eye by at least two
methods
37. Calculate Bifocal trial lens Rx
Round up Near Add power to higher + 0.25 value.
Calculate Spherical equivalent (Best sphere value)
for toric Rx's.
Round-up spherical value to higher - 0.25 step
.
Apply vertex calculations for Distance sphere
powers
38. Check Binocular Visual performance –
Overall subjective performance for distance and
near activities
Allow adaptation for 30 minutes
Carefully note down start up trial lens power for
each eye
If visual performance is "acceptable" for patient
- dispense trial lens for 5 days home trial
"Acceptable" performance is Binocular
distance vision 6/9 & near N8
39. If distance vision is poor
Add –0.25DS for distance power of the
dominant eye, if not good.
Reduce near add by +0.50DSfor
dominant eye, if not good.
Go to enhanced monovision (Dominant
eye with SV distance Rx and non-
dominant eye with bifocal).
40. If near vision is poor
Add +0.25DS for near power of non-
dominant eye, if not good.
Increase near add by +0.50DS for non-
dominant eyes, if not good.
Increase near add by +0.50DS for both
eyes, if not good.
Go to enhance monovision (Dominant
eye with bifocal and non-dominant eye
with single vision near Rx)
41. If distance and near vision both are poor
Add –0.25DS for distance power of
dominant eye and add +0.25DS for
near power of non-dominant eye, if not
good.
Increase near add by +0.50DS for non-
dominant eye and reduce near add by
+0.50DS for dominant eye
Go to enhance monovision.
42. Introducing ACUVUE
BIFOCAL
8.5 Base Curve / 14.20 Diameter8.5 Base Curve / 14.20 Diameter
Distance Power: + 4.00 to - 6.00 DDistance Power: + 4.00 to - 6.00 D
- 0.25 D steps including plano- 0.25 D steps including plano
Near Add Power: +1.00 to + 2.50 DNear Add Power: +1.00 to + 2.50 D
+ 0.50 D steps+ 0.50 D steps