Presbyopia is the loss of eye's ability to focus on near objects with age due to a hardening of the lens. It typically begins around age 40-45 when the eye's natural lens loses elasticity. Symptoms include difficulty seeing objects close up, which is worse in low light. Presbyopia is treated with reading glasses, bifocals, or progressive lenses to add magnification for near vision. Multifocal contact lenses and refractive surgery are also options. The condition is normal and inevitable with aging and affects over 1 billion people worldwide.
When parallel rays of light enter the eye ((with accommodation relaxed) and do) and do not come to a single point focus on or near the retina.
Types of Astigmatism:
Sign & Symptoms:
Management:
This presentation explain about retinoscope, the instrument, its history, its types, the procedure and different cases also the advantages and disadvantages of the instrument and the working lens
Accommodation/ Accommodation of Eye, Measurement of Accommodation of Eye (hea...Bikash Sapkota
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Measurement of Accommodation of eye:
Amplitude, Facility,
Relative Accommodation, Fatigue, Lag,
Dynamic Retinoscopy
Presentation Layout:
-Introduction to accommodation of eye
-Mechanism
-Components
-Measurement of accommodation of eye
- Amplitude
- Facility
- Relative accommodation
- Lag
-Dynamic Retinoscopy
Accommodation
-dioptric adjustment of the crystalline lens of the eye
- to obtain clear vision for a given target of regard
-process by which the refractive power of eye is altered
- to ensure a clear retinal image
For further reading
-Clinical Procedures in Optometry by J.D. Bartlett, J.B. Eskridge, J.F. Amos
-Primary Care Optometry by Theodere Grosvenor
-Borish’s Clinical Refraction by W.J. Benjamin
-Clinical Procedures for Ocular examination by Carlson et al
-American Academy of Ophthalmology
-Optometric Clinical Practice Guideline by American Optometric Association
-Internet
Follow me to get in touch with optometric and ophthalmic updates
When parallel rays of light enter the eye ((with accommodation relaxed) and do) and do not come to a single point focus on or near the retina.
Types of Astigmatism:
Sign & Symptoms:
Management:
This presentation explain about retinoscope, the instrument, its history, its types, the procedure and different cases also the advantages and disadvantages of the instrument and the working lens
Accommodation/ Accommodation of Eye, Measurement of Accommodation of Eye (hea...Bikash Sapkota
CLICK HERE TO DOWNLOAD FULL PPT ❤❤ https://healthkura.com/measurement-of-accommodation-of-eye/ ❤❤
Dear viewers Check Out my other piece of works at ❤❤❤ https://healthkura.com ❤❤❤
Measurement of Accommodation of eye:
Amplitude, Facility,
Relative Accommodation, Fatigue, Lag,
Dynamic Retinoscopy
Presentation Layout:
-Introduction to accommodation of eye
-Mechanism
-Components
-Measurement of accommodation of eye
- Amplitude
- Facility
- Relative accommodation
- Lag
-Dynamic Retinoscopy
Accommodation
-dioptric adjustment of the crystalline lens of the eye
- to obtain clear vision for a given target of regard
-process by which the refractive power of eye is altered
- to ensure a clear retinal image
For further reading
-Clinical Procedures in Optometry by J.D. Bartlett, J.B. Eskridge, J.F. Amos
-Primary Care Optometry by Theodere Grosvenor
-Borish’s Clinical Refraction by W.J. Benjamin
-Clinical Procedures for Ocular examination by Carlson et al
-American Academy of Ophthalmology
-Optometric Clinical Practice Guideline by American Optometric Association
-Internet
Follow me to get in touch with optometric and ophthalmic updates
this PPT summarizes the echanism, theories, components of Accommodation as well as the physiological decline of it giving rise to Presbyopia. It aims to deliver the clinical features, developmental theories and evidence based trend of correcting Presbyopia.
Presbyopia/ Methods of Presbyopic Addition Determination (healthkura.com)Bikash Sapkota
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Presbyopia and techniques of measurement
A fantastic presentation in the topic "Presbyopia and techniques of measurement"
A detailed information about presbyopia, techniques of presbyopic add determination and different correction methods.
Informative slide presentation on presbyopia for ophthalmology residents, ophthalmologists, optometrists, ophthalmic assistants, ophthalmic technicians, ophthalmic nurses, medical students, medical professors, teaching guides.
Presentation Contents:
--Introduction to presbyopia
-Types of presbyopia
-Risk factors
-Symptoms and signs
-Refractive error and presbyopia
-Methods of determining near add.
-Management of presbyopia
In a nutshell..
- The evaluation and management of presbyopia are important because significant functional deficits can occur when the condition is left untreated
- Undercorrected or uncorrected presbyopia can cause significant visual disability and have a negative impact on the pt.'s quality of life
- Finally, every tentative addition should be adjusted according to the particular needs of the patient
For Further Reading:
-Clinical Procedures in Optometry by J.D. Bartlett, J.B. Eskridge, J.F. Amos
-Primary Care Optometry by Theodere Grosvenor
-Borish’s Clinical Refraction by W.J. Benjamin
-Clinical Procedures for Ocular examination by Carlson et al
-American Academy of Ophthalmology
-Optometric Clinical Practice Guideline by American Optometric Association
-Internet
Follow me to get in touch with optometric and ophthalmic updates.
Troubleshooting bifocals and Market Availability in Nepal
Bifocals in Anisometropia
Prismatic Effect in Bifocal
Bifocal Prescription
Bifocals in High Astigmatism
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Adv. biopharm. APPLICATION OF PHARMACOKINETICS : TARGETED DRUG DELIVERY SYSTEMSAkankshaAshtankar
MIP 201T & MPH 202T
ADVANCED BIOPHARMACEUTICS & PHARMACOKINETICS : UNIT 5
APPLICATION OF PHARMACOKINETICS : TARGETED DRUG DELIVERY SYSTEMS By - AKANKSHA ASHTANKAR
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
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.
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...Oleg Kshivets
Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
2. DEFINITION
• Greek presbys elderly; opos eye
• Presbyopia is the irreversible loss of the
accommodative ability of the eye that occurs due
to aging
• It is a normal physiological state due to the loss
of the accomodative capacity with the passage
of time.
3. EPIDEMIOLOGY
• Worldwide in 2005 over 1.04 billion
• By the year 2020 the worldwide prevalence is expected
to rise to 1.37 billion
• The average age of those first reporting symptoms of
presbyopia is between 42 and 44 years of age
• early loss of accommodative ability can be induced by
certain systemic disease, medications, and trauma.
4. PATHOPHYSIOLOGY
Lenticular and extralenticular theories
• Lenticular
sclerosis of the nuclear lens tissue,
decreased distance between ciliary muscle and lens
equator
lens capsule with age becomes thicker,less extensible and
brittle
5. Extralenticular
age related hyalinization of ciliary processes and ciliary
muscles
loss of elasticity in the zonules
even decreasing resistance of the vitreous humor against
the accommodating lens capsule
6. • In emmteropic eye far point is infinity and near point
varies with age
7 cm at 10yrs age
25-40,33-45
• At 10 yrs amplitude of accomodation
A=100/7 =14D
40 yrs A=100/25=4D
• Since we keep the book at 25 cm can read comfortably
till 40 yrs
• After 40 yrs the NPA decrease beyond normal working
range leading to presbyopia
7. Some of the theroies include
1.Helmholtz theory
2.Coleman theory
3. Schachar theory
9. IN PRESBYOPIA
ciliary muscle contraction ceases
posterior zonular fibres pull the ciliary
muscle backward
increases tension on the zonular fibres
increase in lens diameter, decrease in lens
thickness and a flattening of the anterior and
posterior lens surface curvatures
decrease in optical power
10. SCHACHAR’S THEORY
ciliary muscle contracts
equatorial zonular tension is
increased
anterior and posterior zonules are
simultaneously relaxed
central surfaces of the lens
steepen
peripheral surfaces of the lens
flatten
11. • Presbyopia results from growth of equatorial diameter of
the lens
• with age,the perilenticular space is reduced and ciliary
muscle contraction no longer tense the zonules and
expand coronally
• Based on this theory introduded new sx for presbyopia
scleral expansion bands
12. CATENARY THEORY
• Proposed by coleman
• Says that lens zonules and anterior vitreous comprises
of a diaphram b/w AC and vitreous
13. ciliary muscle contracts
initiates a pressure gradient between
the vitreous and aqueous
compartments
anterior capsule and the zonule form
a trampoline shape or hammock
shaped surface
steep radius of curvature in the center
of the lens with slight flattening of the
peripheral anterior lens
ACCORDIND TO THIS THEORY
presbyopia occurs d/t increase
lens volume with age that results
in a reduced response of anterior
radius of curvature to the vitreous
pressure gradient created by
ciliary body contarction
14. CAUSES FOR PREMATURE PRESBYOPIA
• Uncorrected hypermetropia
• Premature sclerosis of crystalline lens
• Presenile weakness of ciliary muscle
• Chronic simple glaucoma
16. SYMPTOMS AND SIGNS
• Difficulty in near vision initially in evening and dim light
and latter even in good light
• Asthenopic symptoms like headache d/t fatigue of ciliary
muscles
• Intermittent diplopia due to associated disturbances of
convergence
All symptoms aggravated by fatigue illness fever or other
chronic conditions
SIGNS reduced amplitude of accomodation
20. Basic principles
• Find ref error for distance n correct it first
• Find presbyopic correction needed in each eye
seperately and add it to distance correcction
• Presbyopic add should leave atleast 50% acomodation
in reserve
• Near point should be taken consideration according to
profession of patient
• Do not give over correction
• Additional correction for intermediate distance may be
required
21. Trial method
• Trial method
– Patient with Rx in DV, test to 40 cm (or habitual distance of NV)
well lit
– Mono and/or binocularly
• Cover LE and go on adding +0.25D in the RE until the patient sees
clearly
• The same for LE
• Refine the result adding 0.25D binocularly
22. Age method
– Empirical method based on clinical experience
– Patient with Rx for DV
– Reading test at a habitual distance in NV with convex
lens of appropriate power
– There are approximated addition tables depending on
age
– Refine the result adding 0.25D binocularly
23. • The difference b/w distance correction and the strength
needed for near vision is called ADD
• BUT the add should be given considering the working
distance of patient
24. Amplitude of Accommodation and Age
(Donder’s Table)
Age (years) Amplitude (D) Age (years) Amplitude (D)
10 14.00 45 3.50
15 12.00 50 2.50
20 10.00 55 1.75
25 8.50 60 1.00
30 7.00 65 0.50
35 5.50 70 0.25
40 5.00 75 0.00
25. • Comfortable vision at near uses less than or
equal to half of the available amplitude of
accommodation
• Near work becomes difficult when the
amplitude of accommodation is less than
5.00D
26. • Working distance at 40 cm requires 2.50D of
accommodation
– Patient A has 5.00D of accommodation
• He can use up to 2.50D of accommodation comfortably
• Therefore, he has just enough accommodative power for
reading at 40 cm, and no reading glasses are required
– Patient B has 3.00D of accommodation
• He can use up to 1.50D of accommodation comfortably
• Therefore, he needs an additional 1.00D of accommodative
power for reading at 40 cm, and +1.00D reading glasses are
required
Example
27. • Monofocal lenses
– Useful for static, long-term tasks
– The glasses should be taken off to
see from distances
• Bifocal lenses
– For NV and DV
• Progressive lenses
– For DV, NV and intermediate
distances
– There are peripheral areas with
optical aberrations
– Very precise adaptation
29. surgical treatment
• Surgery
– Laser in-situ keratomileusis (LASIK)
• More for presbyopic hyperopia than presbyopia
myopia at the moment
– Multifocal intraocular lens (IOL)
– Conductive keratoplasty (monovision)
– Scleral expansion