This document discusses techniques for measuring corneal thickness, known as pachymetry. It begins by introducing pachymetry and its importance in assessing corneal health and thickness. It then describes 12 techniques for measuring corneal thickness, including the gold standard of ultrasonic pachymetry. The document provides details on the principles, advantages, and disadvantages of each technique. It concludes by discussing the clinical utility of pachymetry in procedures like LASIK and for conditions like glaucoma and keratoconus.
Keratometer is an ophthalmic instruments and has a very important role in optometry field specially for IOL power calculation, Contact lens fitting, to rule out corneal pathology and its progression ie Keratoconus, PMCD.
Keratometer is an ophthalmic instruments and has a very important role in optometry field specially for IOL power calculation, Contact lens fitting, to rule out corneal pathology and its progression ie Keratoconus, PMCD.
To know Humphrey visual field analyser
To know about various types of perimetry
To identify field defect
To recognize that field defect is due to glaucoma or neurological lesion
To know that field defect is progressive or not
Interpretation of HVFA
Scleral contact lenses , types, uses in various ocular conditions.
An in-depth and unbiased details of these lenses as a therapeutic and also as a drug - delivery system in modern ophthalmology.
A must read for all Ophthalmologists and Optometrists.
To know Humphrey visual field analyser
To know about various types of perimetry
To identify field defect
To recognize that field defect is due to glaucoma or neurological lesion
To know that field defect is progressive or not
Interpretation of HVFA
Scleral contact lenses , types, uses in various ocular conditions.
An in-depth and unbiased details of these lenses as a therapeutic and also as a drug - delivery system in modern ophthalmology.
A must read for all Ophthalmologists and Optometrists.
LASIK or Lasik (laser-assisted in situ keratomileusis), commonly referred to as laser eye surgery or laser vision correction, is a type of refractive surgery for the correction of myopia, hyperopia, and an actual cure for astigmatism, since it is in the cornea. LASIK surgery is performed by an ophthalmologist who uses a laser or microkeratome to reshape the eye's cornea in order to improve visual acuity. For most people, LASIK provides a long-lasting alternative to eyeglasses or contact lenses.
The planning and analysis of corneal reshaping techniques such as LASIK have been standardized by the American National Standards Institute, an approach based on the Alpins method of astigmatism analysis. The FDA website on LASIK states,
"Before undergoing a refractive procedure, you should carefully weigh the risks and benefits based on your own personal value system, and try to avoid being influenced by friends that have had the procedure or doctors encouraging you to do so."
The procedure involves creating a thin flap on the eye, folding it to enable remodeling of the tissue beneath with a laser and repositioning the flap.
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.
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
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
- 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
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
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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
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.
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.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
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
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
3. INTRODUCTION :
Pachymetry (Greek words: Pachos= thick+metry) is term used for
measurement of corneal thickness.
It is important indicator of health status of the cornea especially
of corneal endothelial function.
The thickness of cornea was first reported in ancient textbooks
on physiological optics (Helmholtz and Gullstrand).
5. CORNEAL THICKNESS IN NORMAL EYES
It ranges from 0.7-0.9 mm at the limbus and varies
between 0.49-0.56 mm at the center.
The CCT reading of 0.7 mm or more is indicative of
endothelial decompensation.
Peripheral corneal thickness is asymmetric so that
temporal cornea is thinnest followed by the inferior
cornea.
6. CORNEAL THICKNESS IN NEWBORNS AND
CHILDREN :
Is similar to that of adult cornea.
It has been found that cornea on day one is significantly thicker and
decreases in thickness as child grows older.
The average corneal thickness in infants is 585±52 microns.
The superior peripheral cornea is thinnest in newborn.
7. Normal Values
Normal corneal thickness – 500-575 microns.
Abnormal results
Abnormally thick or thin measurements may indicate –
corneal thinning.
Corneal edema
Lower or higher than suspected IOP.
8. FACTORS AFFECTING CCT :
Higher in young patients, male patients and diabetic
patients.
The mean CCT in black children is thinner than that
of white children.
CCT does not correlate with refraction or systemic
hypertension.
10. 1.ULTRASONIC PACHYMETRY :
Broadly accepted as method of choice, regarded as the gold
standard.
PRINCIPLE :
Instruments functions by measuring the amount of time
(transmit time) needed for ultrasound pulse pass from one end
of transducer to descemet’s membrane and back to transducer.
Corneal thickness=transmit time × propagation velocity)/2
Speed of sound in cornea : current standard is 1640 m/sec
11. COMPONENTS :
PROBE HANDLE - It has piezoelectric crystal that emits
an ultrasonic beam of 20 MHz
TRANSDUCER – It sends ultrasound rays through the
probe to the cornea and receives echoes from the cornea.
TIP - The diameter of the tip should not be more than
2mm.
12.
13. ADVANTAGES DISADVANTAGES
• Faster ,simpler and easy to use. • Contact method.
• Consistent and eliminates
interoobserver variation.
• Accuracy is dependent on the
perpendicularity of the probe’s
application to the cornea.
• Portable • Reproducibility relies on the precise
probe placement on the center of the
cornea.
• Dry(no coupling medium
required)
• Low resolution.
• Can be used intraoperatively. • Not accurate in edematous cornea.
14. High resolution ultrasound machine which images anterior segment of
the eye.
Using a 50-MHz imaging probe or high-frequency UBM, reproducible
images of the cross-sectional anterior chamber anatomy with high
resolution are achieved.
12.5–50 MHz probe , the depth of penetration is lesser (4mm)than
conventional ultrasound.
2. ULTRASOUND
BIOMICROSCOPY:
15. ADVANTAGES DISADVANTAGES
• AS+ Corneal thickness • The main limitation of UBM is that it
requires a water-bath coupling media
and a very experienced examiner.
• Useful in cases where cornea is opaque • Contact method and patient to lie
supine
• Various layers of cornea can be
identified.
• Cannot be used intraoperatively.
16. 3.MANUAL OPTICAL PACHYMETER:
This was the original method to measure
corneal thickness.
The instrument contains two Plano glass
plates that splits the image of the corneal parallelepiped.
There are two methods to measure corneal thickness.
Just touch method.
Overlap method.
The corneal thickness is then directly read from the scale.
Range is 0-1.2mm, with a least gradation of 0.02 mm.
17. ADVANTAGE DISADVANTAGE
• Non contact method. • Lack of accuracy in measurements,
the usual range of error with an
optical pachymeter is ±2%
• Lack of repeatability.
• Requires slit lamp and therefore has
poor portability and cannot be used
in operating room.
18. 4. SPECULAR PACHYMETRY :
This is the oldest method to measure corneal thickness.
PRINCIPLE : This measures the distance between the
anterior and the posterior surfaces of cornea and depends
on the focusing of light rays through front back cornea
unlike sound waves in ultrasound pachymeter.
2 types 1.contact
2.Non contact
19.
20. ADVANTAGES DISADVANTAGES
• Operator independent. • The exact point where reading is taken is
not known.
• Non invasive. • Time consuming.
• Simultaneous measurement of
cell count.
• Less reproducible.
• Impractical to use in operation room.
• Clinical use is limited to corneas free of
edema, scarring, deposits or opacities
that may distort light transmission.
21. 5.SLIT LAMP PACHYMETER:
Elevation based system which uses scanning slit
technology.
Capable of assessment of multiple functions thickness
profile, anterior and posterior topography, elevation,
and anterior chamber depth.
PRINCIPLE : It measures anterior and posterior
elevations by comparing it to a best fit sphere.
22. Demonstration of slit-lamp adapted ultrasonic pachymetry. The ultrasound probe is
inserted into the Goldmann tonometry mount, and under joystick control, it can be
softly and precisely used to touch the surface of the cornea.
23. ADVANTAGES DISADVANTAGES
• It gives wide field pachymetry
measures across the entire cornea.
• It overestimates corneal thickness by
5%
• It also identifies the thinnest part of
cornea.
• Tendency to underestimate corneal
thickness in keratoconic, post PRK,
and post-Lasik eyes.
• Corneal alignment is not required • The measurements are adjusted for
normal prolate shape of cornea.
Change of shape may interfere with
the reconstruction algorithms
• Can be used to calculate optical
zones in corneal refractive surgeries.
• Decreased accuracy in measuring
corneal thickness when clinically
significant haze is present.
24. 6. ANTERIOR SEGMENT OPTICAL
COHERANCE TOMOGRAPHY :
High resolution, non-contact OCT customized
anterior segment.
Gives color coded map of corneal thickness.
25.
26. ADVANTAGES :
Non contact
Rapid acquisition during the pachymetry scan ensures an
accurate and repeatable pachymetry map.
High resolution
It measures and documents both corneal flap thickness and
residual stromal thickness immediately following LASIK
surgery.
Measures through corneal opacity.
27. 7. OPTICAL LOW COHERENCE REFLECTOMETRY:
The instrument is attached
to a slit lamp.
Measure corneal thickness
to a precision of 1micron.
PRINCIPLE:
Based on Michelson interferometer. It uses diode laser
beam.
28. ADVANTAGES DISADVANTAGES
• Precise 1 micron measurement. • Measures only central corneal
thickness.
• Automatic alignment.
• Non-contact.
• Real-time data acquisition and
display.
• Convenient and easy.
• Variability of measurement is
significantly lower.
• Intraoperative measurements
possible.
29. 8. CONFOCAL MICROSCOPY:
This unique method offers the ability to examine objects at
high magnification ranging from 20 X to 500 X.
It also measures thickness of each layer by using
computerized scanning system providing the total corneal
thickness in studied area.
Beside endothelium examination also measures endothelial
cell count (density) which is comparable to specular
microscopy.
It offers the possibility to visualize structures posterior to
haze, scars or edema in the cornea.
30.
31. ADVANTAGES DISADVANTAGES
• Moderate to good repeatability,
particularly for measurements of thin
layers such as epithelial and bowman’s
layer thickness.
• Poor agreement with ultrasound
pachymetry, it apparently
overestimates corneal thickness.
• Following LASIK surgery, flap
thickness can also be obtained.
• The precision of measurements with
this technique will vary with contact
lens hydration, post-lens tear film
thickness and observation angle.
• The Z-scan curve can be used to assess
the level and location of corneal haze
associated with the various corneal
dystrophies.
• Slower data acquisition.
• Poor penetration of corneal opacity.
32. 9. LASER DOPPLER INTERFEROMETRY :
It is a noncontact technique that uses a dual-beam
infrared laser Doppler interferometry to measure
corneal thickness.
There is limited data available in the literature
regarding this technique.
33. 10. PENTACAM :
It is3-dimensional (3D) rotating scheimpflug.
It can perform five functions in 2 sec.
1. Scheimpflug image of anterior segment.
2. Pachymetry
3. 3-D anterior chamber analyzer
4. Corneal topography.
5. Cataract analyzer.
34. ADVANTAGES DISADVANTAGES
• Non invasiveness, non contact. • It underestimates the corneal
thickness in comparison to
ultrasonic pachymetry.
• Even minute eye movement are
captured and corrected
simultaneously.
• Gives precise representation and
repeatability.
APPLICATIONS:
1. Preoperative planning for corneal refractive surgery
2. Glaucoma screening
3. IOP modification with regard to corneal thickness
4. Keratoconus detection and quantification.
35. 11. PACHYCAM :
Compact and portable non-contact pachymeter with built in keratometer. It
can be mounted on slit lamp. It automatically corrects IOP.
Image acquisition is done with help of a 3-D alignment screen.
ADVATAGES :
1. Non contact.
2. Compact, portable and light weight.
36. 12. OCULAR RESPONSE
ANALYZER :
Newer modality for measuring biomechanical properties of cornea.
Utilizes a rapid air impulse and measures delays in inward and outward
applanation of cornea resulting in two different pressure values
The difference in two pressure values gives corneal thickness.
38. USE IN LASIK
Essential prior to a Lasik procedure for ensuring
sufficient corneal thickness to prevent abnormal
bulging of cornea ( ectasia). Differences in CCT
between pre op and intra op readings.
Differences in central corneal thickness between
pre op and intra op reading. Intra op readings are
always used for setting blasé length and depth of
incision.
39. USE IN GLAUCOMA
CCT statistically significant predictor of development of glaucoma.
In congenital glaucoma to assess amount of corneal edema.
For applying correction factor in actual IOP determination.
Results suggested that IOP measurements need to be adjusted for
abnormally thick or thin corneas.
The target IOP is lower for a thin cornea and higher for thick
cornea.
• Eyes with thick corneas have a true IOP that is lower than the
measured IOP.
• Thus individuals with thicker cornea may be mis- classified as having
ocular hypertension.
40. FACTS ABOUT CCT IN GLAUCOMA :
Bechmann in the yr. 2000 found following association of CCT with
different forms of glaucoma.
Increased CCT measurement are found in patients with ocular
hypertension, which can lead to falsely elevated IOP readings.
Decreased CCT is found in patients with low tension glaucoma, resulting
in falsely reduced IOP measurements.
CCT is found to be lower in patients with Pseudoexfoliation syndrome
(PXS) and in POAG.
There is no difference in corneal thickness in individuals with Pigmentary
glaucoma and PACG.
42. CORNEAL TRANSPLANTS GRAFTS
Assessing candidates for penetrating
keratoplasty(corneal transplant)
Post operative follow up of keratoplasty patients to
determine endothelial cell function and its
recovery and to become alert to early graft
decompensation.
43. KERATOCONOUS
Keratoconous is associated with corneal thinning.
Available evidence indicates that ultrasonic
corneal pachymetry is not as accurate as
videokeratography in diagnosing keratoconus.
False +ve and false –ve rates are unacceptably
higher than those obtained by videokeratography.
44. CLINICAL UTILITY
ASSESSING CORNEA THINNESS:
as in corneal disorders like Terriens and Pellucid
marginal degenerations , keratoconus,keratoglobus ,
post LASIK ectasia.
Other cases of corneal decompensation as in herpetic
endothelitis.
CONTACT LENS CARE:
To access corneal edema.
45. TAKE HOME MESSAGE :
The methodologies used in these techniques are based on either ultrasonic or
optical principles.
While each of the methods have a peculiarity of their own, all have been described
as reliable.
Keep in mind that systematic differences exist between the different techniques
and result in different values.
As a result, the measurements cannot simply be substituted between the different
modalities.