OCT Angiography is a non-invasive imaging technique that uses light to visualize the vascular structures of the retina and choroid in 3D without dye injection. It works by detecting the movement of red blood cells between repeated B-scans of the same retinal location. The software splits the volume cube into slabs corresponding to the inner retina, middle retina, outer retina, and choroid. OCTA provides detailed visualization of the retinal vasculature compared to traditional angiography and allows quantification of vascular parameters. It has various clinical applications including for retinal diseases like AMD and diabetic retinopathy as well as anterior segment evaluation.
Optical coherence tomography angiography optovue a very basic lecture detailing the new advancement of dyeless angiography by spectral domain OCT system and SSADA and Motion correction algorithm
Optical coherence tomography angiography optovue a very basic lecture detailing the new advancement of dyeless angiography by spectral domain OCT system and SSADA and Motion correction algorithm
Role of imaging in glaucoma management gunjan chadha
Glaucoma is chronic progressive optic neuropathy in which structural damage( Optic Nerve Head and Retinal Nerve Fiber Layer) proceeds the functional deterioration( Visual Field loss).
Hence structural imaging plays an important role in early diagnosis and follow up of a patient of glaucoma
Most retinal surgeons are trained to create formal retinal drawings of the fundus.
Retinal drawings are useful to document pathology, although more and more people now prefer fundus photographs.
Can be used for serial follow up of patients to document changes in the pathology.
Role of imaging in glaucoma management gunjan chadha
Glaucoma is chronic progressive optic neuropathy in which structural damage( Optic Nerve Head and Retinal Nerve Fiber Layer) proceeds the functional deterioration( Visual Field loss).
Hence structural imaging plays an important role in early diagnosis and follow up of a patient of glaucoma
Most retinal surgeons are trained to create formal retinal drawings of the fundus.
Retinal drawings are useful to document pathology, although more and more people now prefer fundus photographs.
Can be used for serial follow up of patients to document changes in the pathology.
OCT is a great technology,Many ophthalmologist find very difficult to understand it ,SO I have tired to simplify it as much as possible .Hope everyone can understand now onwards the basic about OCT .
Every feedback s most welcomed sothat i can improve further in coming days
Please email your feedback to me in the following address
yourgyanu@gmail.com
optical coherence tomography is a new tool that makes retinal diagnosis easier. the above ppt includes a detailed and precise notes on OCT and its interpretation.
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.
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
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
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.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
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.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
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
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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
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
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
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...
Oct angiogram
1. OCT Angiogram
Dr Md Afzal Mahfuzullah
MCPS.FCPS.
Fellowship in Vitreo Retina
Assistant Professor
Department of Ophthalmology
Bangabandhu Sheikh Mujib Medical University
2. OCT A
OCT-Angiography is a new, non-invasive diagnostic method through
which the vascular structures of the retina and choroid may be
visualized in three dimensions without the need for contrast agent
injection
3. Through acquisition software and more advanced hardware,
OCTAngiography enables imaging of the retinal vascular flow.
4. Principle
• OCT-Angiography is based on the principle of diffractive particle
movement detection, such as red blood cells,
• on sequential OCT B-scans performed repeatedly at the same retina
location, therefore showing the presence of blood vessels.
5. Principle Cont
• The method is based on differences between the B-scans to generate a
movement-related contrast.
• Specially a contrast related to erythrocyte movement in the vascular
system.
6. Principle Cont
• To generate the image of the retinal microvascularization, each B-scan
of the examination pattern is consecutively repeated several times.
• The contrast comparisons on consecutive B-scans at the same location
reveal some areas with a contrast change over time and some areas
with a constant contrast.
7. Principle Cont
• The temporal change in contrast in a specific location is attributed to
the movement of erythrocytes, which therefore indicates the location
of the vessels.
8. Scan architecture
• As every OCTA obtained is essentially a cube scan, it is a three-
dimensional (3D) assessment of the retinal vasculature unlike
traditional fluorescein or ICG angiography, which is two dimensional.
• Evaluate the scans from the inner retinal surface right down to the
choroid in a continuous manner.
9. Scan architecture,cont
• OCTA machines have taken the cube and split it into slabs to reflect a
known anatomic layer of the retinal vasculature, referred to as
autoseg-mentation.
10. Software slabs
• The AngioVuesoftware on the Optovue OCTA splits the volume cube
up into the following four slabs:
• 1. Inner retinal slab extends from 3 μm below the internal limiting
membrane to 15 μm below the inner plexiform layer. This incorporates
the known anatomic location of the superficial retinal vascular plexus,
which is generally what we see on traditional FA .
11. Software slabs
• Middle retinal slab extends from 15 μm below the inner plexiform
layer to 70 μm below the inner plexiform layer and incorporates the
known location of the deep retinal capillary plexus.
• This plexus is poorly seen on traditional FA and beautifully seen on
OCTA.
12. Software slabs
• Outer retinal slab extends from 70 μm below the inner plexiform layer
to 30 μm below the retinal pigment epithelium (RPE) reference line.
• This region anatomically corresponds to a part of the retina within
which there is NEVER any vasculature in a normal individual.
• This slab can be very useful to identify type 2 (subretinal)
neovascular membranes.
13. Software slabs
• Choriocapillaris extends from 30 μm below the RPE reference to 60
μm below the RPE reference.
• It incorporates the choriocapillaris and allows detection of early type
1 (sub-RPE) choroidal neovascular membranes.
14. Software slabs
• FOR the evaluation of some CNVMs, manual manipulation of the
boundaries of the slab to be visualized is best to truly view the extent
and nature of the CNVM complex.
15. Optic nerve head evaluation
• Optic nerve head and peripapillary retina.
• These scans feature an autosegmentation (four zones)
• 1. The optic nerve head.
• 2. Above the optic nerve head or vitreous, which can be used to
evaluate for the presence of new vessels of the disc or a vascularized
hyaloid artery.
16. Optic nerve head evaluation,Cont
• 3. Radial peripapillary capillaries, which can be evaluated for ischemia
and its potential role in glaucoma. These capillaries are seen in
exquisite detail on OCTA, while poorly viewed on traditional
fluorescein and ICG angiography.
• 4. Choroid/lamina cribrosa.
17. Terminologies
• Amplitude/Magnitude/Intensity Variance -These refer to methods
which detect motion or flow by looking for change in the OCT signal
over time as measured by the variance or decorrelation of signal
amplitude, intensity, or their log transforms.
• Phase Variance -Phase variance uses changes in the phase of the OCT
signal as the means of detecting flow.
•
18. Terminologies,cont
• Split-spectrum Amplitude-decorrelation Angiography (SSADA) is an
efficient algorithm which improves the signal-to-noise ratio of flow
detection by maximizing the extraction of flow information from
speckle variation.
• This is achieved by splitting the OCT spectrum, which increases the
number of usable image frames and reduces noise from axial bulk
motion.
19. Analysis in OCTA
• Segmentation:
• OCT angiography produces volumetric flow information.
• To allow for rapid identification and interpretation of pathological
vascular features, segmentation of key anatomic layers is required .
• En Face Projection: En face projection produces two-dimensional
(2D) views of segmented tissue layers
• Slabs and Slices : These refer to the tissue volume used for en face
projection.
• Slabs refer to thick tissue sections such as the inner retina or outer
retina, whereas slices refer to thin sections of a few microns used to
examine fine details.
20. Signal analysis
• Nonvascular Flow Signal
• In OCT angiography, background bulk tissue motion can generally
be subtracted because it is associated with a uniform decorrelation.
• However, the decorrelation signal in some very highly
backscattering structures can still rise above the background in some
instances.
• These include the RPE, hard exudates, regions of pigment
accumulation, thrombosed aneurysms, and retinal hemorrhages.
21. Signal analysis
• Flow Projection Artifact
• Shadowgraphic flow projection artifacts are the result of fluctuating
shadows cast by flowing blood in a superficial vascular bed that cause
variation of the OCT signal in deeper layers.
22. Signal analysis,Cont
• Flow Index and Vessel Density
• 1. The flow index is calculated as the average decorrelation value
(which is correlated with flow velocity) in the selected region.
• 2. The vessel density is calculated as the percentage area occupied by
vessels in the selected region.
• Avascular area is a significant area (larger than the normal gap
between capillaries) devoid of flow signal on an en face angiogram.
23. Signal analysis,Cont
• Nonperfusion (Capillary Dropout) Area
• Nonperfusion area refers to an avascular area that should
normally be vascular.
• For example, on an OCT angiogram of the macula, any retinal
avascular area outside of the FAZ considered retinal nonperfusion
(capillary dropout) area.
24. Signal analysis,Cont
• Neovascularization Area
• Neovascularization area is the sum of pixel areas in a pathologic
neovascular net identified on an en face OCT angiogram.
• In proliferative diabetic retinopathy, the area is of vessel growth
above the ILM.
• In age-related macular degeneration, the area is of
neovascularization in the outer retina
25. FFA / ICGA vs OCTA
• Scans can be acquired in a few seconds and does not require
intravenous injection
• Fluorescein or ICG angiography requires multiple image frames
taken over several minutes and can cause nausea, vomiting and rarely
anaphylaxis.
• The fast and noninvasive nature of OCT angiography also means
that follow-up scans can be conducted more frequently
26. FFA / ICGA vs OCTA,Cont
• Dye leakage in fluorescein angiography is the hallmark of important
vascular abnormalities such as neovascularization and
microaneurysms.
• OCT angiography does not employ a dye and cannot evaluate
leakage.
• OCT angiography detects vascular abnormalities by other methods
based on depth and vascular pattern
27. Additional advantage in OCTA
• Dye leakage and staining do not occur in OCT angiography, the
boundaries, and therefore areas, of capillary dropout and
neovascularization can be more precisely measured.
• Conventional angiography is two- dimensional, which makes it
difficult to distinguish vascular abnormalities within different layers.
• The 3D nature of OCT angiography allows for separate evaluation
of abnormalities in the retinal and choroidal circulations.
28. OCTA in Clinical Use
• ARMD
• CNVM
• Diabetic Retinopathy
• Arterial and Venous occlusive disease
• CSCR
• Mac Tel 2
• Glaucoma
• Anterior Segment ( Cornea, Conjunctiva, Iris )
30. OCTA for Anterior Segment Vasculature
• The ocular surface and iris vasculature are not easily accessible, and
fluorescein angiography is rarely performed for such evaluations and cannot
be easily repeated.
• OCTA can be repeated over time as often as needed.
• Incredible potential for following disease evolution and monitoring
treatment efficacy.
• Corneal neovascularization is a potentially severe complication in various
corneal diseases and a high-risk factor for corneal rejection following
keratoplasty.
31. The conjunctiva assessment
• The tumor development
• Bleb formation after glaucoma surgery
• Early detection of iris neovascularization is also a major goal when
monitoring ischemic diseases of the retina
32. Technique and difficulty
• To obtain a scan of the anterior segment in the AngioVue OCTA system
,the anterior segment optical adaptor lens (L-CAM) is used.
• A specific anterior module (angiocornea) is used to perform anterior
segment scans.
• Anterior segment OCTA does not tolerate any eye movement of the
patient because even micromovements create transverse artifacts on the
final images.
• Scans cannot be performed when patients are unable to fixate, or have
continuous eye or eyelid movements such as nystagmus or symptoms
causing abnormal blinking rate or blepharospasm.
33. OCTA for Conjunctival Vessel Assessment:
• Application in Glaucoma Surgery
• OCTA is also helpful for documenting the vascular patterns in
conjunctival inflammation or wound healing
• Monitoring bleb formation and evaluating proper functioning of the
filtering bleb.
• Investigative tool to study the conjunctival and episcleral vasculature
changes after trabeculectomy
• Postoperative: the vasculature alterations include much higher vascular
density, dilated and tortuous vessels, and vascular anastomoses.
34. Iris Vessels evaluation
• OCTA of the iris appears to be able to demonstrate vessels difficult to
photograph or to clinically observe by slit-lamp examination
• The iris angiograms show radial iris vessel patterns in normal
lightcolored Eyes.
• In darker iris, the pigment pro- duces shadowing and artifacts that
obscure the vasculature .
35. Bleb evaluation in post trab
• Post-mitomycin C ischemic blebs
• OCTA shows avascular zones.
• Avascular spaces between dense vascular networks may reflect the
presence of aqueous humor and are therefore indicating proper wound
healing and bleb formation.
• Absence of free vessel intervals and increased vessel density may reflect
inflammatory states and early stages of bleb scarring and loss of
functionality
36. Total Retinal Blood Flow
• Fourier-domain OCT utilizes optical phase information to precisely
measure Doppler velocity.
• It measures the axial flow velocity, which is the velocity component in
the direction of the OCT probe beam.
• It provides quantitative measurement of high flow velocities in the retinal
vessels of the optic disc, and is done by scanning multiple con- centric
circles around the optic disc.
37. Total Retinal Blood Flow,Cont
• This technique has been used to investigate TRBF in several ocular
diseases, including DR, retinal vein occlusions, uveitis, and glaucoma.
• In eyes with vein occlusions, the TRBF was reduced in the eye with the
vascular occlusion, when compared to both the fellow eye and the normal
age-matched eyes.
38.
39. Conclusion
• OCTA has rapidly expanded as an imaging modality that has been used to
qualitatively and quantitatively describe changes in retinal and choroidal
vasculature associated pathology.
• It also has the potential to enhance our understanding of the disease
mechanism, since microvascular changes can be correlated to structural
features.
• Currently, OCTA is widely used in the clinical setting to guide treatment
or diagnosis decisions.