Tunica Interna – innermost endothelium of simple squamous epithelium + basement membrane
Arteries – have an “internal elastic lamina” of elastic CT to allow for expansion under pressure
Veins – may have “valves” (folds of endothelium + CT) to prevent backflow of blood due to low pressure Microscopic, very thin-walled vessels comprised of endothelium with basement membrane; allows for filtration and reabsorption Found in all tissues of the body except for those that are “avascular” Usually form branching networks (“capillary beds”) within tissues for increased surface area blood flow into capillaries may be regulated by “pre- capillary sphincters” may have a central or “thoroughfare” channel that provides direct connection between “metarteriole” (terminal end of arteriole) & venule
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away from the tissues.
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away from the tissues.
The urinary system, also known as the renal system or urinary tract, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, control levels of electrolytes and metabolites, and regulate blood pH.
Right Atrium of human heart
This PPT help to understand the external and internal structures of right atrium.
sulcus terminalis on external surface of rt atrium,
crista terminalis on internal side of rt. atrium,
interior is divided into rough anterior part and smooth posterior part ( sinus venarum)
superior and inferior venae cavae drains deoxygenated blood into rt. atrim
there is Eustachian valve to guard the opening of IVC and Thebesian valve to guard the opening of coronary sinus
septal wall presents fossa ovalis with its border limbus fossa ovalis
The urinary system, also known as the renal system or urinary tract, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, control levels of electrolytes and metabolites, and regulate blood pH.
Right Atrium of human heart
This PPT help to understand the external and internal structures of right atrium.
sulcus terminalis on external surface of rt atrium,
crista terminalis on internal side of rt. atrium,
interior is divided into rough anterior part and smooth posterior part ( sinus venarum)
superior and inferior venae cavae drains deoxygenated blood into rt. atrim
there is Eustachian valve to guard the opening of IVC and Thebesian valve to guard the opening of coronary sinus
septal wall presents fossa ovalis with its border limbus fossa ovalis
The circulatory system transports fluids throughout the body;
it consists of the cardiovascular and lymphatic systems.
The heart and blood vessels make up the blood transportation network, the cardiovascular system.
Through this system, the heart pumps blood through the body’s vast system of blood vessels.
The blood carries nutrients, oxygen, and waste products to and from the cells.
VASCULAR CIRCUITS
The heart consists of two muscular pumps dividing the circulation into two components:
pulmonary circulations
systemic circulations or circuit
Pulmonary Circulation
Rt ventricle propels low O2 blood into the lungs via the pulmonary arteries.
CO2 is exchanged for O2 in the capillaries of the lungs.
Then the O2 -rich blood is returned via the pulmonary veins to the Lft atrium.
This circuit, from the right ventricle through the lungs to the left atrium, is the pulmonary circulation.
Systemic Circulation
Left ventricle propels the O2 -rich blood through systemic arteries (the aorta and its branches),
exchanging O2 and nutrients for CO2 in the remainder of the body’s capillaries.
Low- O2 blood returns to right atrium via systemic veins (tributaries of the superior and inferior vena cava).
This circuit, from left ventricle to right atrium, is the systemic circulation.
The cardiovascular system is transport system of body
It comprises blood, heart and blood vessels.
The system supplies nutrients to and remove waste products from various tissue of body.
The conveying media is liquid in form of blood which flows in close tubular system.
Learning Objectives:
Compare and contrast the structure and function
of
Arteries
Veins
Capillaries
ulatory
system
Arteries
Arterioles
Capillaries
Venules
Veins
3 tunics
Lume
The Vessels
Functions:
Distribution of blood
Exchange of materials with tissues
Return of blood to the heart
Structure:
Most have the same basic structure:
– 3 layers surrounding a hollow lumen
astigmatism
AstigmatismAstigmatism Walter Huang, ODWalter Huang, OD Yuanpei UniversityYuanpei University Department of OptometryDepartment of Optometry
2. DefinitionDefinition When parallel rays of light enter the eyeWhen parallel rays of light enter the eye ((with accommodation relaxedwith accommodation relaxed) and do) and do notnot come to a single point focus on or nearcome to a single point focus on or near the retinathe retina
3. OpticsOptics Power in thePower in the horizontalhorizontal plane projects aplane projects a verticalvertical focal line imagefocal line image Power in thePower in the verticalvertical plane projects aplane projects a horizontalhorizontal focal line imagefocal line image
4. OpticsOptics Refraction of light taking place at a toricRefraction of light taking place at a toric surface: the conoid of Sturmsurface: the conoid of Sturm
TONOMETRY • Tonometry is the procedure performed to determine the intraocular pressure (IOP).
3. CLASSIFICATION TONOMETRY DIRECT INDIRECT Indentation Applanation Manometer
4. APPLANATION Contact Non-contact Goldmann Perkins Air-puff Pulse air
5. INDENTATION TONOMETER • It is based on fundamental fact that plunger will indent a soft eye more than hard eye. • The indentation tonometer in current use is that of Schiotz . • It was devised in 1905 and continued to refine it through 1927.
6. PROCEDURE • Patient should be anaesthetising with 4% lignocaine or 0.5% proparacaine. • with the patient in supine position, looking up at a fixation target while examiners separates the lids and lower the tonometer plate to rest on the cornea so that plunger is free to move. •
. Introduction Biomicroscope derives its name from the fact that it enables the practitioner to observe the living tissue of eye under magnification. It not only provides magnified view of every part of eye but also allows quantitative measurements and photography of every part for documentation.
3. • The lamp facilitates an examination which looks at anterior segment, or frontal structures, of the human eye, which includes the –Eyelid –Cornea –Sclera –Conjunctiva –Iris –Aqueous –Natural crystalline lens and –Anterior vitreous.
4. Important historical landmarks De Wecker 1863 devised a portable ophthalmomicroscope . Albert and Greenough 1891,developed a binocular microscope which provided stereoscopic view. Gullstrand ,1911 introduced the illumination system which had for the first time a slit diapharm in it Therefore Gullstrand is credited with the invention of slit lamp.
1. Introduction Gross anatomy Layers Blood supply, drainage and nerve supply
2. INTRODUCTION • Sclera forms posterior 5/6th of external tunic , connective tissue coat of eyeball. • it continues with duramater and cornea • Its whole surface covered by tenon’s capsule • Anteriorly covered by- bulbar conjunctiva • Inner surface lies in contact with choroid • With a potential suprachoroidal space in between
3. Equa THICKNESS OF SCLERA
4. • Thickness varies with individual, with age • Thinner- children, elder, F> M • Thickest posteriorly • Gradually becomes thinner when traced anteriorly • Thin at insertion of extraocular muscle
The pupil is an opening located in the center of the iris that allows light to enter the retina. • Its function is to control the amount of light entering the eye and it does this via contraction (miosis) and dilation (mydriasis) under the influence of the autonomic nervous system
3. • The iris is a contractile structure, consisting mainly of smooth muscle, surrounding the pupil. Light enters the eye through the pupil, and the iris regulates the amount of light by controlling the size of the pupil.
4. The iris contains two groups of smooth muscles: a circular group called the sphincter pupillae. and a radial group called the dilator pupillae.
5. Parasympathetic pathway • First Order – Retina to Pretectal Nucleus in B/S (at level of Superior colliculus) Second Order – Pretectal nucleus to E/W nucleus (bilateral innervation!) Third Order – E/W nucleus to Ciliary Ganglion Fourth Order – Ciliary Ganglion to Sphincter pupillae (via short ciliary nerves) • • •
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
Introduction Transparent,avascular,watch-glass like structure. Forms 1/6th part of outer fibrous coat (Sclera) It is the major refracting surface of the eye
3. Dimensions + Avg horizontal dia =11.75 mm (ant surface) + Avg vertical dia = 11 mm (ant surface ) + Avg dia (post surface)= 11.5 mm + Thickness(centre) =0.52mm + Thickness(peripheral) = 0.67mm + Radius of curvature (ant surface) = 7.8mm + Radius of curvature (post surface)= 6.5mm + Refractive power (ant surface) = +48D + Refractive power(post surface)= - 5D + R.I = 1.376
4. Histology + Epithelium + Bowman’s membrane + Stroma + Dua’s layer + Descemet’s membrane + Endothelium
5. Epithelium + Made up of stratified squamous epithelium + Thickness - 50-90 um + 5-6 layers of cells + Regenerative, entire epithelial layer is replaced every 6-8 days + Made up of 3 types of cells - basal,wing, flattened cells + Cells are attached by to each other by means of desmosomes & maculi occludents
6. Bowman’s membrane + Acellular,Non regenerative + Made up of condensed collagen fibrils. + Thickness - 12um + Resistant to infection & injury.
LIMBUS… • The limbus forms the border between the transparent cornea and opaque sclera, contains the pathways of aqueous humour outflow, and is the site of surgical incisions for cataract and glaucoma
2. Anatomical Limbus: Circumcorneal transitional zone of the conjunctivocorneal & corneoscleral junction Conjunctivo-corneal junction: • Bulbar conjunctiva is firmly adherent to underlying structures • Substantia propria of the conjunctiva stops here but its epithelium continues with that of the cornea. Sclero-corneal junction: • Transparent corneal lamellae become continuous • With the oblique, circular and opaque fibres of sclera
3. CONTINUE…. • In the area near limbus, the conjunctiva, tenon’s capsule & the episcleral tissue are fused into a dense tissue which is strongly adherent to corneo scleral junction.It is preferred site for obtaining a firm hold of the eyeball during ocular surgery. • The limbus is a common site for the occurrence of corneal epithelial neoplasm. • The Limbus contains radially oriented fibrovascular ridge known as the palisades of Vogt that may harbour a stem cell population. The palisades of Vogt are more common in the superior and inferior quadrants around the eye
Diagnosis, Management, and Surgery by Adam J. Cohen, Michael Mercandetti & Brian G. Brazzo. The dry eye , a practical approach by Sudi Patel & Kenny J Blades. Jack J Kanski’s clinical ophthalmology Clinical Anatomy of the Eye by Richard S. Snell & Michael A. Lemp.
3. It is concerned with the tear formation & transport. Lacrimal passage includes : Lacrimal gland Conjunctival sac Lacrimal puncta Lacrimal canaliculi Lacrimal sac Nasolacrimal duct
4. The following components of the lacrimal apparatus are discussed : Embryology Osteology Secretory system Excretory system Physiology
5. Ectodermal origin Solid epithelial buds(first 2 months) Supero
Extraocular musles(EOM) They are six in number Four recti: Superior rectus Inferior rectus Medial rectus Lateral rectus Two oblique muscles: Superior oblique Inferior oblique
3. SUPERIOR RECTUS MUSCLE . Origin Superior part of common annular tendon of Zinn Course Passes anterolaterally beneath the levator At 23 degrees with the globe ‘s AP axis Pierces Tenon s capsule Insertion into sclera by flat tendinous 10 mm broad insertion 7.7 mm behind sclero-corneal junction. 42 mm long 9 mm wide
4. Nerve supply Sup division of 3rd N Blood Supply Lateral Muscular br. of Ophthalmic A APPLIED: SR loosely bound to LPS muscle. • During SR resection- eyelid may be pulled forward narr owing palpebral fissure • In hypotropia pseudoptosis may be present Origin of SR and MR are closely attached to the dural sheat h of the optic nerve pain during upward & inward movements of the globe in RETROBULBAR NEURITIS
Diseases of sclera
2. anatomy • Sclera posterior 5/6th opaque part of the external fibrous tunic of the eyeball.
3. • outer surface }covered by Tenon's capsule. • anterior part } covered by bulbar conjunctiva.
4. Its inner surface lies in contact with choroid with a potential suprachoroidal space in between
5. Thickness of sclera. • thinner }children and in females Sclera • thickest} posteriorly (1mm) • gradually becomes thin when traced anteriorly. • thinnest } insertion of extraocular muscles (0.3 mm). • Lamina cribrosa is a sieve-like sclera from which fibres of optic nerve pass.
6. Apertures of sclera • Anterior • Anterior ciliary vessels • Middle • four vortex veins (vena verticosae) • Posterior • Optic nerve • Long & short ciliary nerves
7. Layers of sclera sclera episclera Sclera proper Lamina fusca thin, dense vascularised layer of connective tissue fibroblasts, macrophages and lymphocytes avascular structure dense bundles of collagen fibres. innermost blends with suprachoroidal and supraciliary laminae of the uveal tract. brownish in colour presence of pigmented cells.
Main physiologic function of cornea is to act as a major refracting medium, so that a clear retinal image is formed. • Normal corneal transparency is result of • 1.anatomical factor such as uniform and regular arrangement of corneal epithelium, peculiar arrangement of corneal lamella and corneal vascularity 2.Physiological factor [ie] relative state of corneal dehydration.
3. • Therefore, any process which upsets the anatomy or physiology of cornea will cause LOSS OF TRANSPARENCY to some degree.
4. FACTORS AFFECTING CORNEAL TRANSPARENCY • CORNEAL EPITHELIUM &TEAR FLIM • ARRANGEMENT OF STROMAL LAMELLA • CORNEAL VASCULARIZATION • CORNEAL HYDRATION • CELLULAR FACTORS AFFECTING TRANSPARENCY
CONJUNCTIVA: ANATOMY , PHYSIOLOGY, SYMPTOMATOLOGY AND CLASSIFICATION Pranay Shinde DNB Resident Deen Dayal Upadhyay Hospital,New Delhi
2. ANATOMY It is the mucous membrane covering the under surface of the lids and anterior part of the eyeball upto the cornea.
3. Parts of conjunctiva • Palpebral; covering the lids—firmly adherent. • Forniceal; covering the fornices—loose—thrown into folds. • Bulbar; covering the eyeball—loosely attached except at limbus.
4. Palpebral conjunctiva • Subtarsal sulcus 2mm from posterior edge of the lid margin. • Richly vascular. • Extremely thin. • Strongly bound to the tarsal plate.
5. Palpebral conjunctiva is subdivided into three parts: 1)Marginal 2)Tarsal 3)Orbital
6. Conjunctival fornices • Transitional region between palpebral and bulbar conjunctivae. • Superior fornix 10 mm from limbus. • Inferior fornix 8 mm from limbus. • Lateral fornix 14mm from limbus. • Medially absent. • Ducts of lacrimal glands open into lateral part of superior fornix.
q Colour Vision Deficiency Presented by : Optometrist (intern) Asma Al-Jroudi Saudi Arabia, Riyadh, King Abdulaziz University Hospital 30 Dec 14
2. • What Is Color Vision Deficiency? • Causes Of Color Vision Deficiency • Types Of Color Vision Deficiency • Tretments Of Color Vision Deficiency • Ishihara’s Test • Conclousion
3. What is Colour Blindness? • Color blindness, or color vision deficiency, is the inability or decreased ability to see color, or perceive color differences, under normal lighting conditions. •This condition results from an absence of color- sensitive pigment in the cone cells of the retina, the nerve layer at the back of the eye.
4. What is Colour Blindness? • Cones are the coulored light receptors in back of the eye: Red light receptors, Blue light receptors and Green light receptors. • Colour blindness occurs when one or more of the cone types are defected.
5. Causes of Color Blindness • Genetic: Many more men are affected than women. • Acquired : Chronic illness, Accidents, Medications and Age.
ANATOMY & PHYSIOLOGY Lecturer: Tatyana V. Ryazantseva
2. Outer eye: Eyelids The eyelids fulfill two main functions: protection of the eyeball secretion, distribution and drainage of tears
3. Lid movement The levator extends from an attachment at the orbital apex to attachments at the tarsal plate and skin. ● The lids are securely attached at either end to the bony orbital margin by the medial and lateral palpebral ligaments. Trauma to the medial ligament causes the lid to flop forward and laterally, impairing function and cosmesis.
4. Innervation - Sensory innervation is from the trigeminal (fifth) cranial nerve, via the ophthalmic division (upper lid) and maxillary division (lower lid). - The orbicularis oculi is innervated by the facial (seventh) nerve. - The levator muscle in the upper lid is supplied by the oculomotor (third) nerve.
5. Blood supply and lymphatics The eyelids are supplied by an extensive network of blood vessels which form an anastomosis between branches derived from the external carotid artery via the face and from the internal carotid artery via the orbit.
6. Blood supply and lymphatics Lymphatic fluid drains into the preauricular and submandibular nodes. Preauricular lymphadenopathy is a useful sign of infective eyelid swelling (especially viral).
Anatomy and Physiology of Aqueous Humor Sumit Singh Maharjan
2. Anatomy
3. Angle of anterior chamber
4. Angle of the Anterior chamber
5. Gonioscopic grading of Angle
6. Aqueous Outflow system
7. Trabecular meshwork
8. Functions of Aqueous Humor • Maintenance of Intraocular pressure • Metabolic role cornea lens vitreous and retina • Optical function • Clearing function
9. Physicochemical properties • volume: 0.31ml (0.25ml in Ant. Chamber and 0.06 in post chamber) • Refractive index: 1.336 • Density: slightly greater than water, its viscocity is 1.025-1.040 • Osmotic pressure: slightly hyperosmotic to plasma by 3-5mosm/l • PH: 7.2 • Rate of formation: 2-2.5microliter/min
10. Biochemical composition • Water: 99.9% • Proteins: 5-16mg/100ml • Amino acids: aqueous/plasma concentration varies from 0.08-3.14 • Non colloidal constituents: conc. of ascorbate, pyruvate, lactate in higher am
Vitreous humour
1. Vitreous Humour
2. General features Vitreous humour is an inert ,transparent , colourless, jellylike, hydrophilic gel that serves the optical functions and also acts as important supporting structures for the eyeball. The vitreous cavity is bounded by anteriorly by the lens and ciliary body and posteriorly by the retina Its weighs nearly 4g Vitreous is an extacellular material composed of approximately 99 per cent water
3. Structure The vitreous body is the largest and simplest connective tissue present as a single piece in the human body Divided into three parts- 1. The hyaloid layer or membrane 2. The cortical vitreous and 3. The medullary vitreous
Vitamins all
1. Vitamins. Definition - Organic compound required in small amounts. Vitamin A Vitamin B1, B2, B3, B5, B6, B7, B9, B12 Vitamin D Vitamin E Vitamin K A few wordsabout each.
2. Sourcesin diet - Many plants(photoreceptors), also meat, especially liver. Fat soluble, so you can get too much, or too littleif absorption isaproblem. Vitamin A - Retinol Retinol (vitamin A) Someuses: Vision (11-cis-retinol bound to rhodopsin detectslight in our eyes). Regulating genetranscription (retinoic acid receptorson cell nuclei arepart of a system for regulating transcription of mRNAsfor anumber of genes).
Tear film
1. TEAR FILM
2. The outer most layer of the cornea. It is the exposed part of the eyeball. FUNCTION It provide smooth optical surface It serves to keep the surface of cornea and conjunctiva moist. It serves as a lubricant for the preocular surface and lids It transfer oxygen from the air to the cornea Prevent infection due to the presence of antibacterial substance like lysozymes,and other protein. It wash away debris and irritants Provides pathway to WBC in case of injury.
3. LAYERS OF TEAR FILM It consist of three layers: 1.Lipid layer 2.Aqueous layer 3.Mucoid layer 1.LIPID LAYER
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Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
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ANATOMY OF BLOOD VESSELS
1. Anatomy of Blood Vessels & their
distribution
Date- 14-11-2017
BY - GAURAV PANDEY
2. Basic Anatomy of Circulatory routes
Arteries
Arterioles
Capillaries
Venules
Veins Carry
blood
away from
the heart
Control
blood flow
into
capillaries
& help
regulate BPAllow for “exchange”
(filtration/reabsorption) of
Connect
capillaries to
veins
Carry blood
towards the
heart
4. Arteries & Veins
Both are comprised of 3 layers of tissue surrounding “lumen”
through which blood will flow: tunica interna, tunica media &
tunica externa
Structural difference between arteries & veins primarily due
to differences in pressure of blood flowing within
5. Arteries & Veins
Tunica Interna – innermost endothelium of simple squamous
epithelium + basement membrane
Arteries – have an “internal elastic lamina” of elastic CT to allow
for expansion under pressure
Veins – may have “valves” (folds of endothelium + CT) to prevent
backflow of blood due to low pressure
6. Arteries & Veins
Tunica Media – middle layer containing smooth muscle (for
contractility/vasoconstriction) & elastic CT (for elasticity)
Arteries – have relatively thick tunica media allowing for
significant vasoconstriction & elasticity
Elastic/conducting arteries – relatively more elastic tissue than smooth
muscle; ie. aorta, pulmonary trunk, etc.
Muscular/distributing arteries - relatively more muscle tissue than elastic
tissue; ie. brachial, femoral, etc.
Veins – relatively thin tunica media therefore no significant
constriction/elasticity
7. Arteries & Veins
Tunica Externa – made of collagenous CT
Arteries – thin layer
Veins – thickest layer of vein, trying to support against gravity &
low pressure
9. Arterioles & Venules
Very small, almost microscopic vessels with only 2 layers of tissue
surrounding lumen
Arterioles – endothelium (tunica interna) + very thin layer of smooth
muscle cells (tunica media); regulate blood flow to tissues & affect arterial
blood pressure
Venules – endothelium (tunica interna) + thin layer of CT (tunica externa)
10. Capillaries Microscopic, very thin-walled vessels
comprised of endothelium with
basement membrane; allows for
filtration and reabsorption
Found in all tissues of the body except
for those that are “avascular”
Usually form branching networks
(“capillary beds”) within tissues for
increased surface area
blood flow into capillaries may be
regulated by “pre- capillary sphincters”
may have a central or “thoroughfare”
channel that provides direct connection
between “metarteriole” (terminal end of
arteriole) & venule
Capillaries can be classified as continuous,
fenestrated, or sinusoids
13. Circulatory Routes – Systemic circuit
Ascending aorta
(gives off coronary
arteries)
Aortic arch
Brachiocephalic trunk
Left common carotid artery
Left subclavian artery
Thoracic (descending) aorta
Abdominal aorta
Common iliac arteries
Arterial blood from left ventricle
into ascending aorta
Venous return to right atrium
through SVC, IVC & coronary
sinus
17. LIVER
Hepatic Portal Vein
Cystic vein
Lt. gastric vein
Splenic vein
Inferior
mesenteric veinSuperior
mesenteric vein
A
O
R
T
A
(blood mixes in
sinusioids)
Hepatic Veins
I
V
C
Hepatic artery
Hepatic portal circulation
Venous blood flow from GIT &
spleen to liver – ensures
delivery of nutrients to liver
first