myphedema: anatomy and physiology

when is it considered lymphedema?

chronic edema of more than 3 months

which body regions does lymphedema affect

legs, arms, trunk, head and neck

what is lymphedema

external manifestation of lymphatic system insufficiency and deranged lymph transport

what is the tonsils do?

stop pathogens

what does bone marrow do?

create and mature T cells

what is thymus do

train T cells

what does the spleen do?

filters blood of pathogens, abnormal cells

what does Peyer’s patches

small intestine immune surveillance and attack

what does the lymph vessels do?

conduct lymph fluid

what does the lymph nodes do?

clean lymph fluid

where are lymph vessels located in the body?

present throughout the body except hair, nails, cornea, and cartilage.

what does the lymph vessels consist of?

capillaries

pre collectors

collectors

trunks

ducts

what are lymph capillaries

larger than blood capillaries

absorb large molecules from interstitium

overlapping ends “swinging flaps

anchoring filaments

what type of squamous is present in lymph capillaries

simple squamous epithelium: flat endothelial cells that overlap

what are lymph pre collectors

connect lymph capillaries to lymph collectors

absorb fluid

what are the walls of the lymph collectors?

tunica intima

tunica media

tunica adventitia

what are lymph collectors

motor units called lymphangions between valves

fluid moved by intrinsic and extrinsic contractions

what is an intrinsic contraction: lymph collector

smooth muscle (autonomic nervous sytem)

what are extrinsic contractions with lymph collectors

breathing

exercise

arterial pulsation

vein negative pressure

compression on skin

where does R and L lumbar trunks take lymph to

from inguinal lymph nodes to cistern chyli

where does the thoracic duct dump into?

left venous angle

where does the R lymphatic duct dump

into r venous angle ¼ lymph

what are lymph nodes

kidney shaped

filter the lymph fluid, removing bacteria, dead cells, and toxins using macrophages

which organ produces lymphocytes

lymph nodes

where are lymphocytes usually lcoated

in adipose tissue; only inguinal LB should be palpable

what are major lymph node locations

cervical

axillary

cisterna chyli

iliac and lumbar lymph nodes 

inguinal

cubital, mediastinal, mammary, shoulder/head/neck, subscapular

what are watersheds

regions that drain to specific lymph ndes

what is anastomoses

connections between lymph collectors; across watersheds