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.
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.
Recent diagnostic advances simplified to assist in easy learning with descriptive pictures.Principles of OCT, HRT, CSLO, GDx and interpretation of the same explained with relevant images. The terms ganglion cell complex, glaucoma probabity score and corneal hysteresis explained.
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
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.
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.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
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Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
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
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.
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
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
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
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
2. Definition
POAG- A chronic, progressive, anterior optic neuropathy that is accompanied by a
characteristic cupping and atrophy of the optic disc with corresponding visual field loss.
Preperimetric glaucoma (PPG) is defined as the presence of characteristic
glaucomatous changes in the optic disc and increased vulnerability to damage in the
retinal nerve fiber layer (RNFL), without the presence of visual field defects
detectible with standard automated perimetry.
3. NEED FOR EARLY DIAGNOSIS
Studies have proved that structural changes in glaucoma (ONH, RNFL)
preceed functional changes
Glaucoma is a continuum.
Optic nerve maybe abnormal WITHOUT glaucoma
This has a great potential value in delaying and avoiding progression of the
disease
4. Indications for early diagnosis
1. Family history
2. Raised IOP
3. Increase in size of cup
4. Difference in size of cup
5. Associated disease state - diabetes mellitus
6. 1. Scanning laser polarimetry
● Scanning laser polarimetry is an imaging technology to
measure peripapillary RNFL thickness
● GDX is a device that uses this technology
● Latest generation - GDX VCC (variable corneal
compensator)
● Evaluates the site of damage before patient experiences
visual loss
● Total chair time less than 3 minutes for both eyes
● Undilated pupils work best, no drops required
● Painless procedure, safe,
7. ● Principle - BIREFRINGENCE
● Phenomenon of double refraction where a ray of light when incident on a
birefringent material is split by polarization into 2 ways taking slight different
paths.
● Main birefringent intraocular tissues - cornea, lens and retina
8. ● In the retina, the parallel arrangement
of the microtubules in retinal ganglion
cell axons causes a change in the
polarization of light passing through
them.
● The change in the polarization of light is
called retardation
● The retardation value is proportionate
to the thickness of the RNFL
9. ● Technique -
● 780nm DIODE laser
● The scan is obtained by the use of an 3.2mm fixed ellipse centered over the optic
disc as seen in reflectance map
● Data is displayed as color coded grids which displays a ‘heat map’ - representing
different levels of retardation and therefore RNFL thickness.
10. ● VCC stands for variable corneal
compensator, which was created to
account for the variable corneal
birefringence in patients.
● Uses the birefringence of Henle’s layer in
the macula as control for measurement of
corneal birefringence
13. ● PATIENT DATA: patient data and quality score - the patient’s name, date of
birth, gender and ethnicity are reported. An ideal quality score is from 7-10.
14. ● FUNDUS/ REFLECTANCE IMAGE -useful to check image quality
● Every image has a Q score representing the overall quality of the scan
● The Q ranges from 1-10, with values 8-10 representing acceptable quality
● This score is based on a no. of factors including - well focussed, evenly
illuminated, optic disc well centered and ellipse is properly around the ONH
15. ● The calculation circle is the area
found in between the two concentric
circles, which measure the TSNIT and
Nerve fibre indicator (NFI)
parameters.
● By resizing the calculation circle and
the ellipse, the operator is able to
measure beyond a large peripapillary
atrophy area
16. RNFL thickness map
● A color coded format from blue to red.
● Hot colors like red and yellow mean high retardation or
thicker RNFL
● Cool colors like blue and green mean low retardation /
thinner RNFL
● A healthy eye has yellow and red colors in the superior and
inferior regions representing thick RNFL regions and blue
and green areas nasally and temporally representing
thinner RNFL areas
● In glaucoma, RNFL loss will result in a more uniform blue
appearance
17. TSNIT map
● TSNIT displays the RNFL thickness values along the calculation circle in relation
to normal range
● Normal eye - typical “double hump” pattern
● Healthy eye - there is good symmetry between the TSNIT graphs of the two
eyes and the two curves will overlap
● In glaucoma - one eye often has more advanced RNFL loss and therefore the 2
curves will have less overlap
18. Green and pink shaded areas of normality, over which a black line is
drawn to demonstrate patient’s RNFL thickness
TSNIT symmetry graph-
R & L superimposed on
each other
19. Deviation map
● Reveals the location and magnitude of RNFL defects over the entire thickness map.
Color coded pixels indicate amount of deviation.
● Compared to the age matched normative database
● Dark blue squares - RNFL thickness is below 5th percentile of the normative
database
● Light blue squares - deviation below the 2% level
● Yellow - deviation below 1%
● Red- deviation below 0.05%
20.
21. Nerve fibre indicator
● An indicator of likelihood that an eye has glaucoma
● Calculated using an advanced form of neural network, called a support vector
machine (SVM)
● Output values range from 1-100
1-30 = low likelihood for glaucoma
31-50 = glaucoma suspect
51+ = high likelihood of glaucoma
23. Review of GDx
● No pupil dilatation
● Rapid data on RNFL
● Large normative database
● Sensitivity and specificity to detect
glaucoma >80%
● Only RNFL information
● Corneal surgery will induce error (if
no VCC)
● Macular pathology is a hinderance
● NFI -proprietary value
STRENGTH LIMITATIONS
24. 2. Confocal scanning laser ophthalmoscopy (HRT)
● CSLO is a rapid, non-invasive, non contact imaging
technology
● Heidelberg Retina Tomography is the major
commercially available instrument that uses this
technology
● 3 generations - HRT, HRT 2, HRT 3
● Gives 3-D images- high resolution
● Principle - spot illumination and spot detection
25. ● Stimulus - 670 micron DIODE laser
● Uses laser light instead of a bright flash of white light to illuminate the retina
● Conjugated pinholes are placed in front of the light source and light detector and allow
only light originating from a determined focal plane to reach the detector.
● Sequential sections are obtained by moving through the whole depth of tissue - in this
case the optic nerve.
● Oscillating mirrors in the HRT redirect the laser beam to the x and y axis (which is
perpendicular to the optic axis). A bi-dimensional image is obtained at each focal plane.
26.
27. What the HRT does
● Once the patient is positioned, HRT 2 automatically performs a pre-scan
through the optic disc to determine the depth of the individual’s optic nerve
● Next, it determines the number of imaging planes to use (range of scan depth
1-4mm)
● Each successive scan plane is set to measure 0.0625mm deeper
● Automatically obtains 3 scans for analysis
● Aligns and averages the scans to create the mean topography image
28. ● A series of 32 confocal images each 256x256
pixels is obtained in a duration of 1.6 secs
● Computer converts 32 confocal images to a
single topographic image in approximately 90
secs.
29. ● Once image is taken, operator indicates the optic nerve contour line over the
reflectance or topography image.
● Reference plane - located 50 microns posterior to the mean height along a 6deg arc
of contour line at temporal inferior sector
● HRT 3 provides ONH stereometric analysis without manual delineation of disc.
● Stereometric parameters are calculated by the machine and analysed by A1 classifier - Relevance Vector
Machine(RVM). Then a Glaucoma Probability Score is created.
34. ● Provides information on exam type (initial report/baseline/follow up), patient
demographic information ( patient name, age, gender, ethnicity, etc) and basic
image information including image focus position and whether astigmatic lenses
were used during acquisition,
PATIENT DATA
35. ● On left upper corner
● A false color image
● Color coded representation of disc
● Superficial areas- darker
● Deep areas - lighter
● Red - cup
● Blue, green - NRR
TOPOGRAPHIC IMAGE
Blue - sloping rim Green - non sloping rim
36.
37. ● On right upper corner in u/l report, below topographic image in OU report
● Brighter areas - higher reflectance - cup
● Darker areas - less reflectance
● Valuable in locating and drawing the contour line around the disc margin
● In the reflectance image the optic nerve head is divided into 6 sectors
● Depending on this patient’s age and overall disc size the eye is then statistically
classified as :
REFLECTION IMAGE
38.
39. ● Height profile along the white horizontal
line in the topography image
● Height profile along the white vertical line
in the topography image
● The subjacent reference line (red) indicates
the location of the reference plane
(separation between cup and NRR)
● The 2 black lines perpendicular to the
height profile denote the borders of the
disc as defined by the contour line.
HORIZONTAL and VERTICAL HEIGHT PROFILE
40. ● After the contour line is drawn around the border of the optic disc, the software
automatically places a reference plane parallel to the peripapillary retinal surface
located 50 um below the retinal surface
● The reference plane is used to calculate the thickness and cross-sectional area of the
RNFL.
● The parameters of area and volume of the NRR and optic cup are also calculated
based on the location of the reference plane. CUP = area of the image that falls below
the reference plane. NRR = above the reference plane
● Normal contour - DOUBLE HUMP - humps correspond to the superior and inferior
NFL, which are normally thicker
MEAN CONTOUR HEIGHT GRAPH
41. ● Green contour line should never go below red ref. Plane. If it does, then contour like
likely not in proper position
● The graph depicts from left to right T-TS-NS-N-NI-TI-T
42.
43. ● Hrt 2- 14 parameters
● HRT 3- 6 parameters
● Each value is designated as
STEREOMETRIC ANALYSIS
46. Glaucoma probability
● New software included in HRT 3
● Based on construction of a 3-D model of ONH and RNFL by using 5 parameters-
cup size & depth, rim steepness, horizontal & vertical RNFL
● Employs artificial intelligence: relevance vector machine and derives probability
of glaucoma of scanned eye after comparing it to a predetermined model
● - probability </= 28% - WNL
● - probability >/= 28% - BL
● -probability >/= 64% -ONL
47. HRT can differentiate between normal
and early glaucomatous eyes with a
sensitivity of 79% to 87% and
specificity of 84% to 90%.
Unlike the MRA, the GPS utilizes the
whole topographic image of the optic
disc, including the cup size, cup depth,
rim steepness and horizontal/vertical
RNFL curvature whereas the MRA uses
only a logarithmic relationship between
the NRR and optic disc areas
48. Quality indicators
● Even luminance
● Sharp borders of topography and reflectance
images
● Good centration of the disc
● Manufacturer’s classification by standard
deviation -->
● <10 = excellent
11-20= very good
21-30= good
31-40= acceptable
41-50= poor
>50 =very poor
49. Review of HRT
● No pupil dilatation
● Rapid 3D data on ONH
● Software available for longitudinal
change analysis
● Operator draws contour line (except
in HRT 3)
● Reference plane affects data
outcome
● Blood vessels often included in rim
area
● Less useful for analysis of macula or
RNFL
STRENGTH LIMITATIONS
50. 3. Optical coherence tomography (OCT)
● It is an imaging technology that measures intensity and echo-time delay of back
scattered and back reflected light from scanned tissues.
● Developed in 1991
● High resolution cross sectional imaging of ONH, RNFL, macula
● Generations - OCT 1,2,3 (stratus), Spectral
● Light source - 820 or 850nm IR DIODE laser
● PRINCIPLE- low coherence interferometry & the ability to differentiate retinal
layers depending on the different time delay of their reflections
51. ● High reflectivity tissues (white and red colors) - NFL, RPE and choriocapillaries
● Low reflectivity tissues (blue and black colors) - photoreceptor layer, choroid,
pockets of fluid
● Advantage- can scan RNFL, ONH and macula
● Resolution - 8-10 microns
55. Peripapillary RNFL scan
● 3.4 mm circular scan around ONH
● RNFL curve starts with temporal quadrant & continues clockwise in RE,
counterwise in LE.
● Thickness values are provided for 4 quadrants & each clock hours
● Classification based on normative database is color coded
- green = WNL
- yellow = borderline
- red = ONL
● Average RNFL is also established.
56.
57. ONH SCAN
● 6 linear scans (length=4mm) ina spoke fashion obtained
● Automatically defines ONH margins at the end of RPE layer (blue cross).
Straight line is drawn joining the blue crosses.
● Reference plane - parallel line drawn 150 microns anterior to previous line
● Tissues above reference plane - rim (Red)
● Tissues below - cup (contour -green & edge - yellow)
● One radial scan is yellow denoting the axis of cross-sectional image in the
printout
58.
59. Ganglion cell complex (GCC) analysis
● Measurement of retinal thickness at the macula in an attempt to
detect early stage glaucomatous damage
60. Review of OCT
● Highest axial resolution
● image can be compared with histology
slides
● Rapid data on RNFL, ONH and macula
● ONH margin determined by device
● No need for pupil dilation
● Detects different pathologies
● Easy to operate, safe
● Limited normative database
● Data originate from only 1 set of
scans
● Limited programs for longitudinal
evaluation glaucomatous
progression
STRENGTH LIMITATIONS
61. Conclusion
● Proven advantages in early diagnosis and monitoring of glaucoma
● Limitations :
● Disability to capture all nuances of appearance as instereo- photographs
● Cannot discriminate glaucoma in difficult optic discs (high myopia , tilted
optic disc)
● Hence , these modalities cannot replace the gold standards of functional and
structural tests but can definitely compliment them in clinician’s decision
making process.