This presentation gives a brief idea about angle of anterior chamber along with its structures and diagnostic methods to grade and visualize the structures.
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
Each eyelid contains a fibrous plate, called a tarsus, that gives it structure and shape; muscles, which move the eyelids; and meibomian (or tarsal) glands, which secrete lubricating fluids. The lids are covered with skin, lined with mucous membrane, and bordered with a fringe of hairs, the eyelashes.
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 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
Each eyelid contains a fibrous plate, called a tarsus, that gives it structure and shape; muscles, which move the eyelids; and meibomian (or tarsal) glands, which secrete lubricating fluids. The lids are covered with skin, lined with mucous membrane, and bordered with a fringe of hairs, the eyelashes.
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.
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
The choroid, also known as the choroidea or choroid coat, is a part of the uvea, the vascular layer of the eye. It contains connective tissues, and lies between the retina and the sclera. The human choroid is thickest at the far extreme rear of the eye (at 0.2 mm), while in the outlying areas it narrows to 0.1 mm. The choroid provides oxygen and nourishment to the outer layers of the retin
Histology of the eye by a very good docotor in iraqi uni collage of medZaraVvv
Simple explanation about the eye, which is very specific and illustrated about histology of the eye it’s going to be very benefit and is actually very good actually benefit me very much it is published by a doctor in iraqi university. It’s illustrates the matter in a very simple way, and helps the student to understand the matter. Help to understand the histology and anatomy of the eye.
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
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
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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.
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
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
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.
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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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.
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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.
Triangles of Neck and Clinical Correlation by Dr. RIG.pptx
Angle of anterior chamber
1. Moderator: Dr. Deepika M
Presenter: K. Sahithi Reddy
2K14, KAMS&RC
ANGLE OF ANTERIOR
CHAMBER
Date: 10-07-2017
2. INDEX :
• Anterior Chamber
• Angle of anterior chamber
• Development
• Aqueous outflow system
• Importance of Angle of anterior
chamber
• Diagnostic modalities
3. ANTERIOR CHAMBER :
• Anterior chamber is an angular
space.
• It is the space formed
Anteriorly by the posterior
surface of cornea
Posteriorly by the lens within
the pupillary aperture, anterior
surface of iris and a part of cilary
body
4. • Anterior chamber Is 3mm deep
and it contains 0.25ml of
aqueous humour.
• Anterior chamber depth is
shallower in the hypermetropic
eye than the myopic eye.
• It is also shallower in children
and older people.
• Chamber depth decreases by
0.01mm/year of life
5. • Chamber depth is slightly diminished during accommodation, partly
by increased lens curvature and partly by forward translocation of
lens.
• Chamber deepens by 0.06mm for each diopter of myopia.
6. • 1. Schwalbe’s line
• 2. Trabecular Meshwork
• 3. Scleral spur
• 4. Anterior most part of ciliary body
• 5. Root of Iris
7. Development :
By 7th week, angle is occupied by mesenchymal cells from neural
crest cells to develop trabecular meshwork.
In posterior aspect, iris is formed from advancing bilayered optic cup
Corneal endothelium meets derivative of iris at 15th week to
demarcate the angle.
Angle deepening continues even after birth.
8. Schwalbe’s Line:
• This marks the anterior border
of angle and represents
termination of descemet’s
membrane.
• Seen as glistening white line in
gonioscopy.
9. • Prominance of Schwalbe’s line is known as posterior embryotoxon,
seen in Axenfield Reiger’s Anomaly.
10. Pigments along Schwalbe’s line are known as
Sampaolesi’s line, seen in pigmentary glaucoma &
pseudoexfoliation Syndrome.
11. • Schwalbe’s line marks transition
from
Trabecular to cornea
endothelium.
Termination of the Decemet’s
membrane.
Insertion of trabecular meshwork
into corneal stroma.
12. TRABECULAR MESHWORK:
• It is a sieve like structure made
up of connective tissue lined by
trabeculocytes, which have
contractile and phagocytic
properties.
• Its main function is in drainage
of aqueous humour.
13. • The meshwork is roughly triangular in cross section;
• Apex is at the Schwalbe’s line
• Base is formed by the scleral spur and ciliary body.
14. • It is morphologically and
functionally divided into 3 types :
1. Uveal meshwork
2. Corneoscleral meshwork
3. Juxtacanalicular
tissue/meshwork
15. 1. UVEAL MESHWORK:
• Innermost part of TM
• It comprises of trabecular bands, which have a
central core that mainly consists of collagenous
fibers distributed with a few elastic fibers, and is
lined by trabecular endothelial cells resting on a
thick basement membrane
• The trabecular bands run mostly in radial fashion
• Trabecular apertures size is 25-75 micrometer.
• The trabeculocytes usually contain pigment
granules.
16. 2. THE CORNEOSCLERAL MESHWORK:
• Consists of a series of thin, flat, perforated
connective tissue sheets arranged in a
laminar pattern
• The central core consists of collagenous
and elastic fibres
• Each trabecular beam is covered by a
monolayer of trabecular endothelial cells,
supported by basement membrane.
• The pore size is smaller than the uveal
meshwork (5-50micro metre)
17. Ultrastructure of Meshwork:
• Both uveal and corneoscleral bands are composed of 4 concentric layers
1. An inner connective issue core is composed of collagen fibres, with
64nm periodicity. The central core contains collagen types I and III and elastin.
2. Elastic fibres are arranged in a spiraling pattern with periodicity of
100nm.
18. 3. Cortical zone also called as glassy membrane
4. An outer endothelial layer provides a continuous covering over the
trabeculae.
19. TRABECULAR ENDOTHELIAL CELLS
• Larger, more irregular and have less prominent borders than corneal
endothelium.
• Joined by gap junction and desmosomes, which provide stability.
• 2 types of microfilaments:
1. Actin filaments : cell periphery, around nucleus, cytoplasmic
processes.
Cell contraction, phagocytosis, pinocytosis and cell adhesions.
Regulating the shape and cytoskeletal organization.
20. • 2. Intermediate filaments:
Numerous, composed of
vimentin and desmin.
Imparts the contractile and
motility functions.
21. 3. JUXTACANALICULAR MESHWORK:
• Also known as cribriform meshwork
• The outermost part of TM
• Lies adjacent to the inner wall of Schlemm’s
canal
• It consists of a lose network of fine fibrils,
elastic like fibres and elongated fibroblasts
life cells and ground substance full of
glycosaminoglycans and glycoproteins
• The spaces between cells are upto
10micrometre.
22. SCHLEMM’S CANAL
• Schlemm’s canal is a circular lymphatic like
vessel in the eye that collects aqueous humour
from the anterior chamber and delivers it into
the episcleral blood vessels via aqueous veins.
• Schlemm’s canal is often divided into different
parts by bridges or septa. The septa cross the
lumen of the canal mostly in an oblique
direction. They are often fixed to the outer wall
of the canal at places where the collector
channels begin.
• The structure of the outer wall of schlemm’s
canal differs very much from that of the inner
wall.
23.
24. INNER WALL OF SCHLEMM’S CANAL
• The endothelial lining of the canal
consists of a complete monolayer of
flat endothelial cells that do not rest
on a complete basement membrane.
• The subendothelial cell layer is not
complete and consists of elongated,
star like cells oriented predominantly
in a radial anteroposterior direction
• The lateral walls of the endothelial
cells are joined by tight junctions
25. • Micropinocytotic vesicles are present at the apical and basal surfaces
of the cells
• Some “vacuoles’’ have openings on the inner and outer sides, thus
forming transcellular microchannels.
26. OUTER WALL OF SCHLEMM’S CANAL
• The endothelial lining is single-
layered, with a well developed
basement membrane
• The cells do not possess
transcellular microchannels.
• The adjacent stroma consists of
collagenous and elastic like
fibers intermingled with
fibroblasts.
27. COLLECTOR CHANNELS
• Schlemm’s canal is connected to
episcleral and conjunctival veins
by a complex system of
intrascleral channels.
• Two systems of intrascleral
channels have been identified:
(a) Indirect system
(b) Direct system
28. (a) INDIRECT SYSTEM
• Indirect system consists of 15-
20, finner channels, which form
an intrascleral plexus before
eventually draining into the
episcleral venous system
29. (b) DIRECT SYSTEM:
• Direct system consists of large
caliber vessels, which run a short
intrascleral course and drain
directly into the episcleral
venous system, they are about
6-8 in number and also called as
aqueous veins.
• These aqueous vessels terminate
into the episcleral and
conjunctival veins in laminated
junction- it is called LAMINATED
VEIN OF GOLDMANN
30. EPISCLERAL AND CONJUNCTIVAL VEINS
• Most aqueous vessel are
directed posteriorly, with most
of these draining into episcleral
veins, whereas a few cross the
subconjunctival tissue and drain
into conjunctival veins
31. • The episcleral veins drain into
the cavernous sinus via the
anterior ciliary and superior
ophthalmic veins,
• While the conjunctival veins
drain into superior ophthalmic
or facial veins via the palpebral
and angular veins
32. SCLERAL SPUR:
• Wedge shaped circular ridge.
• Pale, translucent narrow strip of
scleral tissue.
• Scleral spur is composed of a
group of fibres known as “scleral
roll”
• Scleral roll is composed of 75-
85% collagen and 5% elastic
tissue.
34. • Contraction of longitudinal ciliary
muscle opens up trabecular spaces.
• Scleral spur prevents ciliary muscle from
causing Schlemm’s canal to collapse.
• Individual scleral spur cells are
innervated by unmyelinated axons.
• Varicose axons characteristic of
mechano-receptor nerve measure stress
in the scleral spur due to ciliary muscle
contraction or changes in IOP.
35. CILIARY BAND:
• It marks the posterior most part
of the angle.
• Represents the anterior face of
ciliary body between its
attachment to the scleral spur
and insertion of iris.
• Width depends on the level of
iris insertion.
• Wide in myopes
• Narrow in hypermetropes.
36. • Ciliary band appears as a
grey/dark brown band.
• It consists of longitudinal fibres.
• The contraction of longitudinal
muscle, opens the trabecular
meshwork and schlemm’s canal.
37. INNERVATION:
• Derives from the supraciliary nerve plexus and the ciliary
plexus in the region of scleral spur.
• Both sympathetic adrenergic and parasympathetic and
sensory innervation – present
38. Nerve endings contain mechanoreceptors which are
located in scleral spur :
act as proprioceptive tendon organs for the ciliary
muscle,
contraction myofibroblast scleral spur cells
baroreceptor function in response to change in IOP
39. IMPORTANCE OF ANGLE OF ANTERIOR CHAMBER:
• For classification of glaucoma
• To note the extent of neovascularization
• To assess angle recession
• History or evidence of inflammation
• For evidence of neoplastic activity
• Degenerative or developmental anomaly
• For planning of treatment – iris neovascularization and
laser procedure.
40. DIAGNOSTIC MODALITIES:
1) Van-herick test
2) Flashlight/ pentorch test
3) Ultrasound biomicroscopy
4) Optical coherence tomography
(OCT)
5) Gonioscopy
41. 1) VAN-HERICK TEST:
• It is a slit lamp estimation of angle
• To perform this test, slit lamp is made very bright and thin. It is
offset 600 temporally to the slit lamp oculars. The temporal sclera
is illuminated and the slit lamp beam is brought slowly towards
the cornea until the anterior chamber is first identified. The
thickness of the cornea is compared to the depth of the
peripheral anterior chamber
• At, present, this test is most widely adopted method for
evaluating the ACA in community optometric practice.
44. 2) PENTORCH EXAMINATION:
• Depth of anterior chamber can be evaluated by focusing a beam of
light on the temporal limbus, parallel to the surface of iris.
• In normal or deep AC the beam will pass through directly, illuminating
the opposite limbus.
• In shallow AC, the anterior placement of or bowing forward of the iris
obstruct the light and shadow is observed on the medial half of iris.
45. 3) ULTRASOUND BIOMICROSCOPY:
• UBM is a close contact (non-invasive) immersion technique.
• UBM is performed with the patient supine, positioning that
theoretically causes the iris diaphragm to fall back. This deepens the
anterior chamber and opens the angle.
• With UBM, only 1 quadrant can be imaged at a time.
• There is a risk of infection or corneal abrasion due to the contact
nature of the examination.
46.
47. 4) OPTICAL COHERENCE
O TOMOGRAPHY(OCT)
• OCT is a non contact, non invasive light
based imaging modality.
• Provides image resolution higher than
that of UBM of anterior segment in
cross section with AS-OCT, 4 quadrants
can be scanned at once(multiple cross-
sectional image of the anterior
chamber angle)
• The working principle of OCT is similar
to ultrasound which uses echoes to
locate structures within the body.
48. 5) GONIOSCOPY:
• Gonioscopy is an essential diagnostic tool and examination technique
used to visualize the structures of the anterior chamber angle.
• All gonioscopy lenses eliminate the tear-air interface by placing a
plastic or glass surface adjacent to the front of the eye.
• Methods of gonioscopy:
1) Direct
2) Indirect
49. DIRECT GONIOSCOPY: Procedure
• Direct gonioscopy is most easily performed with the patient supine
and in the operating room for an examination under anesthesia with
4% xylocaine.
• It is performed using a direct goniolens and either a binocular
microscope or a slit-pen light.
• The lens is positioned after saline or viscoelastic is placed on the eye,
which can act as a coupling device.
• The lens provides direct visualization of the chamber angle in an erect
position
51. KOEPPE LENS:
• Koeppe lens is the prototypical diagnostic
goniolens
• Koeppe gonioscopy is an unsurpassed
method for viewing the chamber angle in
the operating room.
52. • Koeppe-type lenses are also quite useful for performing funduscopy.
• When used with a direct ophthalmoscope and a high-plus-power
lens, they can provide a good view of the fundus, even through a very
small pupil.
• These lenses are especially helpful in individuals with nystagmus or
irregular corneas.
• Inconvenience is the major disadvantage of the direct gonioscopy
systems.
53. • BARKAN’S LENS:
The Barkan goniolens has served as the prototypical
surgical goniolens for surgical goniotomy. Has no rod
• SWAN-JACOB LENS:
The Swan-Jacob goniolens has been modified for
goniosurgery and is now one of the most popular models
for angle surgery.
54. ADVANTAGES- Direct Gonioscopy:
• Observer’s height can be changed to look deep or get a better look at
the angle structure’s
• As it is done in supine position it can be used for sedated, comatosed
patients and in children
• Useful in examining the fundus with small pupil
• Straight on the view
• Panoramic view of the angle structure’s
• Comparison of angle recession
• Causes less distortion of AC
56. INDIRECT GONIOSCOPY: Procedure
• Indirect Gonioscopy is performed under the slit lamp.
• The patient and the examiner must be positioned in a comfortable fashion.
• A drop of topical anesthetic is then applied to the conjunctiva of both eyes.
• If using the Goldmann lens, contact gel is placed in the concave part of the
lens.
• If using a Posner or similar type lens, a drop of artificial tears can be placed
on the concave surface.
• The patient is then asked to open both eyes and look upwards.
• The examiner can then pull down slightly on the lower lid and places the
lens on the surface of the eye.
57. • The patient is then asked to look straight ahead.
• Most examiners choose to start with the inferior angle as it is usually
more open, and the pigmentation of the trabecular meshwork is
slightly more prominent, allowing for easier identification of the angle
structures.
• Continue identifying all angle structures in all 4 quadrants, and then
repeat with the other eye.
59. GOLDMANN LENS:
• It is a three mirror contact lens
• For examination of the entire
ocular fundus and the
iridocorneal angle.
• The advantage of a longer mirror
is that it often permits binocular
observation of the lateral
sections of the ocular fundus
60. OBSERVATION:
• Central lens(1) - Posterior pole
• 730 mirror(2) - Equator
• 670 mirror(3) - Ora serrata
• 590 mirror(4) - Iridocorneal angle
61. ZEISS GONIOLENS:
• 4 identical mirrors angled at 640 which allow
examination without rotation of the lens
• ADVANTAGE: Coupling material not required
as the posterior curvature of the lens is equal to
the corneal curvature
• Easy to perform when mastered
• Indentation gonioscopy can be performed
• DISADVANTAGE: difficult to master
• Does not stabilize the globe
62. • SUSSMAN LENS:
It is similar to Zeiss Lens except that it has no handle
• POSNER LENS:
It is a modified Zeiss Lens with a handle
63. ADVANTAGES- Indirect Gonioscopy:
• Preferred by most
• Quick, convenient
• No special equipment needed
• Slit lamp is used, which provides variable
magnification and illumination
• Can create corneal wedge
• Allows differentiation of appositional and
synechial angle closure
64. DISADVANTAGES:
• Mirror image can be confusing
• Inadvertent pressure on the cornea:
exaggerates the degree of angle narrowing in the Goldmann lens
opens the angle in four mirror lenses
68. REFERENCES:
• Glaucoma, 6th edition, Comprehensive Ophthalmology, A K Khurana.
• Gross and Microanatomy of Angle of the Anterior Chamber,
Glaucoma, Volume 1, 3rd edition, Modern Ophthalmology, L C Dutta
and Nitin K Dutta.
• Parsons’ Diseases of the Eye, 22nd edition.
• Shield’s textbook of Glaucoma, 8th edition.