The Lymphnode

Short note on lymph node

Lymph nodes are collections of lymphoid tissue at strategic points

Small and medium sized lymph vessels open into lmph nodes

The lymph runs through 8 – 10 nodes before reaching the blood stream

Structure

Capsule – fibrous tissue – forms trabeculae (partitions)

Substance of the lymph node is made of lymphatic tissue

Contains lymphocytes and macrophages

4 – 5 afferent lymph vessels enter the lymph node

One efferent lymph vessel carries lymph away from the node

Lymph node – has a hilum – through which an artery enters and a vein and efferent lymph vessel leave

Situation

Lymph nodes – deep and superficial groups

For head & neck – deep and superficial cervical nodes

Upper limbs – nodes in the elbow regions – deep and superficial axillary nodes

Lower limbs – deep and superficial nodes including popliteal nodes and inguinal nodes

Breast – axillary nodes

Thoracic cavity – parasternal, intercostal, brachiocepalic, mediastinal, tracheobronchial, bronchopulmonary and eosophageal nodes

Pelvic and abdominal cavities – nodes associated with the blood vessels supplying the organs and close to the main arteries i.e. The aorta and external and internal iliac arteries.

Functions of Lymph Nodes

Filtering and phagocytosis

Proliferation of lymphocytes

Activated T and B lymphocytes multiply in lymph nodes

Antibodies produced by sensitised B-lymphocytes enter lymph and blood from the node