This document discusses various refractive errors including astigmatism, aniseikonia, and anisometropia. It defines astigmatism as a refractive error where light fails to come to a single focus on the retina due to unequal refraction in different meridians. It describes the different types of regular and irregular astigmatism. Aniseikonia is defined as an anomaly of binocular vision where the ocular images are unequal in size or shape. Anisometropia is when the total refraction of the two eyes is unequal. The document discusses the symptoms, investigations, and treatment options for these refractive errors including spectacles, contact lenses, and refractive surgery.
Detailed instumentaion and use of manual Lensometer and just a outline of automated lensometer.
I have used the picture of manual lensometer with out the parts describtion because i have explained orally by showing the picture..
Hope u all like it and may help you in learning better. :)
Detailed instumentaion and use of manual Lensometer and just a outline of automated lensometer.
I have used the picture of manual lensometer with out the parts describtion because i have explained orally by showing the picture..
Hope u all like it and may help you in learning better. :)
To know Humphrey visual field analyser
To know about various types of perimetry
To identify field defect
To recognize that field defect is due to glaucoma or neurological lesion
To know that field defect is progressive or not
Interpretation of HVFA
Fitting an Astigmatic Patient is really a challenging.Though fitting a Toric Cornea is another challenge in CL Dispensing practice.This Slide will give you a basic considerations in RGP Toric lens.
To know Humphrey visual field analyser
To know about various types of perimetry
To identify field defect
To recognize that field defect is due to glaucoma or neurological lesion
To know that field defect is progressive or not
Interpretation of HVFA
Fitting an Astigmatic Patient is really a challenging.Though fitting a Toric Cornea is another challenge in CL Dispensing practice.This Slide will give you a basic considerations in RGP Toric lens.
Aniseikonia [ophthalmology description for medical students ]Madhuri Kureti
concise description of aniseikonia which is a condition wherein the images projected to the visual cortex from the two retinae are abnormally unequal in size and /or shape
A refractory error is a very common eye disorder. It occurs when the eye cannot clearly focus the images from the outside world. The result of refractory errors is blurred vision ,which is sometimes so severe that it causes visual impairment.
Similar to Aniseikona , anisometropia & astigmatism (20)
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
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
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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
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.
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
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
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.
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
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
2. REFRACTION
Refraction of light occurs when light passes from one
medium to another of different refractive index.
3. REFRACTIVE PHYSIOLOGY
Light rays are focused on the retina because they are refracted
passing through the cornea and lens (Snell’s Law)
Corneal refractive power is constant
Lens refractive power is modifiable with accommodation
4. EMMETROPIA
Adequate correlation between axial length and refractive power
Parallel light rays fall on the retina (relaxed accommodation)
Fovea
Light rays
5. ASTIGMATISM
• Type of refractive error wherein the light fails to
come to a single focus on the retina
• Unequal refraction of light in different meridia
• Resulting in blurred vision
6. • Based on axis of the principal
meridia:
• Regular astigmatism – principal
meridia are perpendicular
• Irregular astigmatism - principal
meridia cannot be defined
E.g. Keratoconus, Corneal scars
TYPES OF ASTIGMATISM
7. Regular astigmatism
The refractive power changes regularly from one meridian
to the other
Aetiology
Corneal – curvatural abnormalities
Lenticular – rarer
- Curvatural: congenital abnormalities in curvature
- Positional: d/t tilting or oblique placement of the lens
- Index : DM and cataract
9. With the rule astigmatism
• Vertical meridian is steeper than horizontal meridian
• Eyes see vertical lines more sharply than horizontal
lines
• Requires concave cylinders at 180 ͦ+ /- 20 ͦ
• Or convex cylinders at 90 ͦ +/- 20 ͦ
10.
11. Against the rule astigmatism
• Horizontal meridian is steeper than vertical meridian
• Eyes see horizontal lines more sharply than vertical
lines
• Requires concave cylinders at 90 ͦ +/-20 ͦ
• Or convex cylinders at 180 ͦ+/-20 ͦ
12. Oblique astigmatism
• Two principle meridians lies somewhere
between the axis defining either with-the-rule
or against-the-rule astigmatism
• Complementary (45 ͦin one meridian,135 ͦ in
other meridian)
18. Optics of regular astigmatism
• Parallel rays of light are not brought to focus on a point
but form focal lines
• Configuration of rays refracted from an astigmatic
surface– STURM’S CONOID
• Distance between to focal lines– focal interval of Sturm
(measures the degree of astigmatism)
19. Symptoms
Blurring of vision
• Transient blurring of vision
• Relieved by rubbing or closing eyes
• Tries to focus only on one meridian, meridian near to
emmetropia (mostly vertical) is chosen
• Point of light appears tailed off
• A line appears as a succession of strokes fused into
blurred image
20. Asthenopic symptoms
• Includes tiredness of eyes
• Headache(mild frontal ache to violent explosions of
pain)
• Dizziness
• Irritability, fatigue
• Symptoms more common in patients with
Low astigmatism
Hypermetropic astigmatism
21. Symptoms
• Tilting of head- to reduce image distortion.
• Half closure of lids – high astigmatism in an effort to
make a stenopaeic slit
• Rubbing of eyes, hyperaemia of lid margin recurrent stye
and chalazia
24. JACKSON’S CROSS CYLINDER
TEST
It is a combination of
two cylinders of
equal strength but
with opposite sign
placed with their axis
at right angles to
each other and
mounted in a handle.
25. COMPUTERISED CORNEAL
TOPOGRAPHY
• Corneal topography
system or
videokeratography
implies computerised
video assisted
technique that
provides detailed
information about
shape of corneal
surface
26. Treatment Options
• Spectacles
• Single vision glasses with cylinder
• Contact lenses
• Toric soft contact lenses
• Rigid gas permeable contact lenses
• Refractive surgery
• Photorefractive keratectomy (PRK)
• Laser in-situ keratomileusis (LASIK)
• Penetrating Keratoplasty (PK)
• Corneal Cross-Linking With Riboflavin and Ultraviolet
Irradiation
27. AAO GUIDELINES
• In children, give the full astigmatic correction
• In adults, try the full astigmatic correction first. Give warning
and encouragement. If problems are anticipated, try a
walking-around trial with trial frames before prescribing
• To minimize distortion, use minus cylinder lenses and
minimize vertex distances
• Spatial distortion from astigmatic spectacle corrections is a
binocular phenomenon. Occlude one eye to verify that this is
indeed the cause of the patient's complaints
28. AAO GUIDELINES
• If necessary, reduce distortion still further by rotating the
cylinder axis toward 180 or 90 (or toward the old axis) and or
by reducing the cylinder power. Balance the resulting blur with
the remaining distortion, using careful adjustment of cylinder
power and sphere.
• Residual astigmatism at any position of the cylinder axis may
be minimized with the Jackson cross cylinder test for cylinder
power.
• If distortion cannot be reduced sufficiently by altering the
astigmatic spectacle correction , consider contact lenses
(which cause no appreciable distortion) or iseikonic
corrections.
29.
30. Irregular astigmatism
• Characterized by an irregular change of refractive power in
different meridia
Etiological types
1. Corneal irregular astigmatism – corneal scars or
keratoconus.
2. Lenticular irregular astigmatism
3. Retinal irregular astigmatism – due to distortion of the
macular area
31. Symptoms:
Defective vision , distortion of objects and polyopia.
Treatment
• Optical – prescribing contact lenses which replace the
ant. Corneal surface.
• Surgical – indicated in extensive corneal scarring and
consists of PK.
32. ANISEIKONIA
• Anomaly of binocular vision
• Ocular images are unequal in size or shape or
both
• Its importance lies in causation of eye strain
which is difficult to assess
33.
34. ETIOLOGY
• Inherent
• Acquired anisometropia of
high degree
Optical
aniseikonia
• Displacement of retinal
elements towards nodal point
in one eye
Retinal
aniseikonia
• Asymmetrical simultaneous
perception in spite of equal
size of two images
Cortical
aniseikonia
36. A – Spherical B – Cylindrical C – Prismatic D – Pincushion E – Barrel
distortion F – Oblique distortion
37. Asymmetrical
i. Prismatic
Image difference increases progressively in one direction
ii. Pincushion
Image distortion increases progressively in both directions, as
seen with high plus correction in aphakia
iii. Barrel
Image distortion decreases progressively in both direction, as
seen with high minus correction
iv. Oblique
Image size remains the same but there occurs an oblique
distortion of shape
38. Symptoms
• Asthenopic symptoms
Occurs when the differences in image size of the two images is
between 0.75 to 5.0%
Headache , difficulty reading, photophobia, difficulty of fixation,
vertigo, etc
• Disturbances of binocular vision
Diplopia occur only if the difference exceeds 5%
• Disturbances in depth perception and spatial disorientations
• Suppression of one eye
39. Treatment
• Optical aniseikonia
- Unilateral aphakia is best corrected by IOL implantation
- Contact lenses are a better choice than spectacles for
correcting anisometropic aniseikonia
- Refractive corneal surgery
• Retinal aniseikonia
- Corrected by treating the causative disease
40. ISEIKONIC LENSES
• Lenses which cause magnification without introducing
any appreciable refractive power by changing the
direction of the pencils of light passing through them
41. ANISOMETROPIA
• Total refraction of the two eyes is unequal
• Difference of 1D in two eyes cause a 2% difference in the
size of the two retinal images
• 5% size difference / 2.5D - well tolerated
• 2.5-4D – individual sensitivity
• >4D – not tolerated
42. • Alternate vision when one of the two eyes is used at a
time
• Occurs when one eye is emmetropic or moderately
hypermetropic and the other myopic
• Patient uses former eye for distant vision and latter
for near vision
• Anisometropia leads to development of squint
43. UNIOCULAR VISION
• If defect in one eye is higher, it may be excluded from
vision at an early stage in life
• The more ametropic eye becomes amblyopic
• This amblyopia from disuse is known as amblyopia ex
anopsia
45. CLINICAL TYPES
Simple
One eye normal, other myopic / hypermetropic
Compound
Both eyes either myopic / hypermetropic
Mixed
One eye myopic, other eye hypermetropic
46. DIAGNOSIS
Retinoscopy under cycloplegia
State of vision- FRIEND TEST / WORTH’S FOUR DOT TEST
FRIEND Test
F, I, N - GREEN
R,E,D - RED
1. The patient wears red green goggles and is seated at
a distance of 6m from the chart
2. Binocular single vision- will read FRIEND at once
3. Uniocular vision – will read either FIN or RED
4. Alternate vision– will read FIN at one time and RED
at other time
47. WORTH’S FOUR DOT
TEST
Sees all four lights in
absence of manifest squint-
normal binocular vision
ARC- sees four lights in
presence of manifest squint
Sees 2 red lights- LE
suppression
Sees 3 green lights- RE
suppression
Sees 2 red and 3 green
alternately- alternate
suppression
Sees 5 lights(2red, 3
green)- diplopia
48. TREATMENT
Glasses
• In children prescribe full refractive difference regardless
of age, presence of strabismus or not, degree of
anisometropia
• The corrective spectacles can be tolerated up to a
maximum difference of 4D,after that diplopia occurs.
• So in children where best corrected visual acuity is
required in both eyes, contact lenses are preferred
49. • In adults, the more ametropic eye is under corrected
• In adults with alternating vision the condition is usually
left alone
CONTACT LENSES
• Advised for higher degrees of anisometropia and for
children
50. • Anisometropic
spectacles-
In these spectacles
margin of the
stronger lens is made
weaker, thus
minimizing the
annoyance of
peripheral prismatic
effect of
conventional lenses
51.
52.
53. OTHER MODALITIES
• Intraocular lens implantation for uniocular aphakia
• Refractive corneal surgery for unilateral
myopia,astigmatism,hypermetropia
• Phakic refractive lenses(PRL) - for 4 to 10D
• Refractive lens exchange(RLE) - for more than 10D