Lecture 1: intro Terminology

Pathology definition

specialty of medical science concerned w/ cause, development, structural/functional changes, and natural history associated with disease

disease definition

definable deviation from a normal phenotype, evident via patient complaints (symptoms), and/or the measurements of a careful observer

etiology definition

cause of disease

pathogenesis definition

stepwise process of disease development

clinical manifestation definiton

signs and symptoms that result

sequala/complication definition

subsequent condition resulting from the disease

general pathology definition

mechanisms of injury, inflammation, and repair common to all tissues

pathway of cell injury

1. normal

2. adaptation

3. reversible injury

4. irreversible injury

5. cell death

nature of necrosis

pathological - uncontrolled injury

nature of apoptosis

regulated, can be physiological (often) or pathological

trigger of necrosis

external insult - ischemia, toxins, trauma, infection

trigger of apoptosis

intrinsic signals - DNA damage, lack of growth factors, development

morphology of necrosis

cell swelling leads to membrane rupture and ghost cells

morphology of apoptosis

cell shrinkage leads to chromatin condensation and apoptotic bodies

what happens to the cell membrane in necrosis

integrity is lost early and the contents spill out

what happens to the cell membrane in apoptosis

integrity is maintained until fragments are phagocytosed

inflammation in necrosis vs apoptosis

there IS acute inflammation in necrosis and contents leak

There is NO inflammation in apoptosis and the fragments are rapidly cleared

hyperplasia definition

increase in cell number

hypertrophy definition

increase in individual cell size

atrophy definiton

decrease in cell/tissue size or number

metaplasia definition

reversible change of one cell type to another

dysplasia definition

disordered growth

duration of acute inflammation

days to weeks

duration of chronic inflammation

weeks to years

dominant cell in acute inflammation

neutrophil

dominant cell in chronic inflammation

lymphocyte and macrophage

type of tissue injury in acute inflammation

edema and pus

type of tissue injury in chronic inflammation

fibrosis and scarring

what happens to vascular tissue in acute inflammation

permeability increases and filled with exudate

what happens to vascular tissue in chronic inflammation

angiogenesis - new blood vessels form from pre-existing ones

onset of acute inflammation

rapid

onset of chronic inflammation

insidious

outcome of acute inflammation

resolution or abcess

outcome of chronic inflammation

fibrosis or granuloma

what is a granuloma

focal aggregate of immune cells that forms in response to a persistent inflammatory stimulus

what are tubercles

granulomas in the lungs of individuals with tuberculosis

what are some ocular granulomatous conditions

• TB can cause choroidal granulomas

• chalazion

• sarcoidosis

what are the 5 cardinal signs of inflammation

1. redness from vasodilation

2. warmth due to increased blood flow

3. swelling due to increased vascular permeability

4. pain due to nerve stimulation

5. loss of function due to tissue damage

definition of regeneration

same cell type replaces damaged tissue

definition of repair

connective tissue/scar replaces damaged tissue (fibrosis)

how does function change with regeneration vs repair

in regeneration, function is preserved

in repair, function may be compromised

edema definition

abnormal fluid accumulation

neoplasia definition

new, uncontrolled growth

hyperkeratosis definition

thickening of keratin layer

hyperemia/injection definition

increased blood flow, visible engorged vessels

ischemia definition

inadequate blood supply

infarction definition

tissue death from loss of blood supply

neovascularization/angiogenesis definition

growth of new, abnormal blood vessels

telangiectasia definition

permanently dilated small vessels

hemorrhage/petechia/ecchymosis definition

bleeding, pinpoint to bruise like

what is the difference between exudate and transudate

exudate is protein rich

transudate is low in protein

what is infiltrate

accumulation of inflammatory cells in tissue

purulent definiton

pus-forming

what does it mean to be granulomatous

organized, chronic inflammation that leads to the formation of granulomas

fibrosis/sclerosis definition

replaced by scar tissue

-itis meaning

inflammation

-osis meaning

abnormal condition/process

-oma meaning

tumor/mass

-pathy meaning

disease of

-algia meaning

pain

hyper- / hypo- meaning

above/excess

below/deficient

causes of conjunctival hyperemia

allergens, infections, irritants, CLs, underlying conditions

symptoms of conjunctival hyperermia

redness, itching, burning, irritation, tearing, foreign body sensation, photophobia

injection definition

dilation/enlargement of blood vessels

what are the characteristics of ciliary flush

• circumlimbal/perilimbal injection

• ring-like pattern of redness around the cornea

• redness is darkest surrounding the cornea

• often associated with uveitis

• deeper episcleral vessels

erythema definition

superficial redness of the skin due to hyperemia in superficial capillaries

what characterizes a corneal ulcer

infiltrate and epithelial loss into the stroma (1:1 ratio)

what is a pannus

superficial fibrovascular growth

what is guttata

descemet’s excrescences

what are keratic precipitates

inflammatory cells on the endothelium

what is band keratopathy

inflammatory cells on the endothelium

papillae appearance

vascular core

mosaic “cobblestone pattern”

follicle appearance

avascular, dome-shaped lymphoid aggregates

what is a symblepharon

adhesion between the palpebral and bulbar conjunctiva

what is blepharitis

inflammation of the eyelid margins

ptosis

lid drooping

ectropion

outward turning

entropion

inward turning

trichiasis

misdirected lashes

what is uveitis

inflammation of the uveal tract

can be anterior, intermediate, or posterior

where is a posterior synechia located

adhesion between the iris and the lens

where is an anterior synechia located

adhesion between the iris and the cornea/angle

what are koeppe

iris nodules on the pupillary margin

what are busacca

iris nodules on the iris stroma and midperipheral iris

what does it mean to find cells

inflammatory cells floating in the aqueous and/or vitreous

what does it mean to find flare

protein leakage causing a hazy beam

what is hypopyon

layered white blood cells

what is hyphema

layered blood

what is a plasmoid/plastic aqueous

fibrin-rich, gelatinous aqueous

what is the horizontal corneal diameter

11.5-12 mm

what is the clinical use of the horizontal corneal diameter/HVID

primary mental ruler for corneal/conjunctival lesions

ANTERIOR SEGMENT

what is the central corneal thickness

about 555 micrometers but can range from 540-560

clinical use: glaucoma risk assessment

what is the central AC depth

about 2.5-4.0 micrometers

clinical use: AC depth estimation

what is the average palpebral fissure height

about 9-10 mm

clinical use: lid position/ptosis assessment

what is the average pupil diameter

about 2-4 mm

clinical use: comparison object for iris/AC findings

what is the average size of the optic disc diameter

1.5-1.8 mm

what is the clinical use of the optic disc diameter

standard fundus sizing unit

POSTERIOR SEGMENT

what is the average disc to fovea distance

about 2.5-3 DD

4-5 mm

clinical use: key landmark for locating the fovea

what is the average macular diameter

3 DD

5-6 mm

clinical use: overall macular span

what is the average fovea diameter

1 DD

clinical use: central macular landmark