The document summarizes key details about aqueous humour, including its composition, production, circulation and role in maintaining intraocular pressure (IOP). Aqueous humour is produced by ultrafiltration and secretion within the ciliary processes. It flows from the posterior to anterior chamber through the pupil. It is drained out of the eye through the trabecular meshwork and uveoscleral outflow pathways. IOP is maintained through a dynamic equilibrium between aqueous production and outflow and can be measured indirectly using tonometry.
The tear film constitutes Three layers :- An outermost lipid (oily) layer An aqueous (watery) layer that makes up 90% of the tear film volume; and A mucin layer that coats the corneal surface.
3. To form smooth optical surface on cornea. To keep the surface of cornea & conjunctiva moist It serve as lubricant It transfer oxygen Provide antibacterial action Wash debris out It provides a pathway for WBC in case of injury
4. Functions of lipid layer Retards evaporation of tear film Prevents the overflow of tears
5. Function of Aqueous Layer Flushes, buffers and lubricates the corneal surface Delivers oxygen and other nutrients to the corneal surface Wash out debris Delivers antibacterial enzymes and antibodies such as lysozyme.
6. Functions of Mucin Layer Spreads tears over corneal surface. Protects the cornea against foreign substances . Makes corneal surface smooth by filling in surface irregularities
The tear film constitutes Three layers :- An outermost lipid (oily) layer An aqueous (watery) layer that makes up 90% of the tear film volume; and A mucin layer that coats the corneal surface.
3. To form smooth optical surface on cornea. To keep the surface of cornea & conjunctiva moist It serve as lubricant It transfer oxygen Provide antibacterial action Wash debris out It provides a pathway for WBC in case of injury
4. Functions of lipid layer Retards evaporation of tear film Prevents the overflow of tears
5. Function of Aqueous Layer Flushes, buffers and lubricates the corneal surface Delivers oxygen and other nutrients to the corneal surface Wash out debris Delivers antibacterial enzymes and antibodies such as lysozyme.
6. Functions of Mucin Layer Spreads tears over corneal surface. Protects the cornea against foreign substances . Makes corneal surface smooth by filling in surface irregularities
The tear film is a complex mixture of substances secreted from multiple sources on the ocular surface, including the lacrimal gland, the accessory lacrimal glands, the meibomian glands, and the goblet cells.
This presentation gives a brief idea about angle of anterior chamber along with its structures and diagnostic methods to grade and visualize the structures.
INTRODUCTIONThe clear fluid filling the space in front of the eyeball between lens and cornea.The aqueous humour supplies nutrition and removes waste from the clear structure in the anterior eye(cornea and lens)The balance between aqueous production and outflow determines the intraocular pressure.
INTRODUCTION
The clear fluid filling the space in front of the eyeball between lens and cornea.
The aqueous humour supplies nutrition and removes waste from the clear structure in the anterior eye(cornea and lens)
The balance between aqueous production and outflow determines the intraocular pressure.
The tear film is a complex mixture of substances secreted from multiple sources on the ocular surface, including the lacrimal gland, the accessory lacrimal glands, the meibomian glands, and the goblet cells.
This presentation gives a brief idea about angle of anterior chamber along with its structures and diagnostic methods to grade and visualize the structures.
INTRODUCTIONThe clear fluid filling the space in front of the eyeball between lens and cornea.The aqueous humour supplies nutrition and removes waste from the clear structure in the anterior eye(cornea and lens)The balance between aqueous production and outflow determines the intraocular pressure.
INTRODUCTION
The clear fluid filling the space in front of the eyeball between lens and cornea.
The aqueous humour supplies nutrition and removes waste from the clear structure in the anterior eye(cornea and lens)
The balance between aqueous production and outflow determines the intraocular pressure.
Let's learn about the relevant anatomy & physiology associated with glaucoma- the angle of the anterior chamber, physiology of aqueous humor circulation, and many more. Happy Learning!
Fluid Therapy is the administration of fluids to a patient as a treatment or preventative measure. It can be administered via an intravenous, intraperitoneal, intraosseous, subcutaneous and oral routes. 60% of total bodyweight is accounted for by the total body water.
Different fluids can be
cyrstalloids, colloids, hypertonic saline, hypotonic saline, ringer lactate.
Title: Sense of Smell
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 primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
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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.
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
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
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
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
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.
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
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Pharynx and Clinical Correlations BY Dr.Rabia Inam Gandapore.pptx
Intraocular pressure and aqueous dynamics
1.
2. It is a clear, colourless, watery fluid filling the
anterior chamber and posterior chamber of
the eyeball.
Volume: 0.31ml
Anterior chamber- 0.25ml
Posterior chamber- 0.06ml
Refractive Index: 1.336
Density : 1.025-1.040 ( greater than water)
pH : 7.2 (acidic)
Rate of formation: 2.3µl/min
3. Composition: constituents of normal aqueous humour are
Water (99.9%)
Solids (0.1%) which includes
1. Proteins (5-16mg%)
2. Amino acid (5mg/kg of water)
3. Non-colloid constituents –
a) Glucose (6.0 millimols/kg)
b) Urea (7 millimols/kg)
c) Ascorbate (0.9 millimols/kg)
d) Lactic acid (7.4 millimols/kg)
e) Inositol (0.1 millimols/kg)
f) Sodium (144 millimol/kg)
g) Potassium (4.5 millimols/kg)
h) Chloride (10 millimol/kg)
i) Carbonates (34 millimol/kg)
Oxygen ( in dissolved state)
4. Composition of aqueous is similar to plasma
except:
High concentration of : Ascorbate, pyruvate
and lactate.
Low concentration of: Proteins, urea and
glucose.
5. The composition of aqueous in anterior
chamber differs from that in posterior
chamber because of metabolic interchange:
Anterior
chamber
Posterior
chamber
HCO3
- Low High
Cl- High Low
Ascorbate Low High
6. It maintains proper intraocular pressure.
It plays an important metabolic role by
providing nutrients and by removing
metabolites from avascular cornea and lens.
It maintains optical transparency.
It also acts as lymph in the eyeball.
7. Aqueous is derived from plasma within the
capillary network of:
1. Posterior segment
2. Ciliary body
3. Iris
The normal aqueous production rate is
2.3µl/min.
8. The system of semipermeable membranes
separating the blood from the ocular cavity is
known as blood-aqueous barrier.
9.
10. Aqueous humour is mainly derived from
plasma within the capillary network of ciliary
processes.
The following processes are involved in the
production of aqueous humour:
1. Ultrafilteration
2. Secretion
3. Diffusion
11. Diurnal variation
Blood pressure
Plasma osmotic pressure
Intraocular pressure
Role of adrenergic innervation, vasopressin
and adenylcyclase
12. Aqueous flows from posterior chamber into
the anterior chamber through the pupil.
In the anterior chamber, there exist a
convection current which results from
temperature gradient between anterior and
posterior parts of anterior chamber.
13. Aqueous flows from posterior chamber into the
anterior chamber through the pupil.
From anterior chamber it is drained out by two
routes:
1. Trabecular outflow
2. Uveoscleral outflow
14. It is the main outlet (90%) for aqueous
drainage.
It consists of :
i. Trabecular meshwork
ii. Schlemm’s canal
iii. Collector channels
15.
16. It is sieve like structure.
It consists of three portions
1. Uveal meshwork
2. Corneoscleral meshwork
3. Juxtacanalicular(endothelial) meshwork
17.
18. This an endothelial lined canal present
circumferentially in the sclearl sulcus.
The endothelial cells present on its inner wall
are irregular, spindle shaped and contains
giant vacuoles.
The outer wall contains smooth flat cells and
contains opening of collector channels.
19.
20. These are also called intra-scleral aqueous
vessels.
They are about 25-35 in number.
They leave the Schlemm’s cannal at oblique
angles to terminate in the episcleral veins.
They do not have valves.
They are divided into two systems:
1. Direct system
2. Indirect system
21. It is responsible for 10% of aqueous drainage.
Aqueous passes across the ciliary body into
the suprachoroidal space and is drained by
the venous circulation in the ciliary body,
choroid and sclera.
Uveoscleral outflow is approximately around
0.3µl/min.
22. Most of the aqueous drains into the episcleral
veins.
These veins ultimately drain into the
cavernous sinus via the anterior ciliary and
superior ophthalmic veins.
23. IOP is the pressure exerted by the intraocular
contents on the coats of the eyeball.
Normal IOP : 10-21 mm of Hg (mean 16 ±
2.5 mm of Hg)
IOP is essentially maintained by the dynamic
equilibrium between formation and outflow of
aqueous humour.
29. It is an indirect method of measuring IOP
using a specialised instrument called
tonometer.
There are two types of tonometry:
1. Indentation or Impression tonometry
2. Applanation tonometry
30. It is based on the principle that a plunger will
indent soft eye more than a hard eye.
When tonometer is placed on the cornea, W
weight of the tonometer acts on A area of cornea
and indents it, displacing a volume Vc. The
tensile force T sets up in the outer coats of the
eye tangentially to the corneal surface opposing
W so that an additional T is added to baseline or
resting IOP (P0) which is artificially raised to a
new value P1.
Tonometer measures the artificially raised IOP P1.
31.
32.
33.
34. Errors inherent in the instrument
Errors due to contraction of extraocular
muscles
Errors due to accomodation
Errors due to ocular rigidity
Errors due to variation in corneal curvature
Errors in scale reading
Blood volume alteration
Moses effect
35. It is based on Imbert-Fick law which states
that pressure inside a sphere P is equal to the
force W required to flatten its surface divided
by area of flattening A
P= W/A
Two types:
1. Fixed Area (variable force) commenly used.
2. Fixed force (variable area).
36.
37.
38. Other commenly used tonometers:
1. Perkin’s applanation tonometer
2. Pneumatic tonometer
3. Air-puff tonometer ( Non contact )
4. Pulse air tonometer
5. Tono pen
