Lymphatics Lab Orientation PDF

LABORATORY ORIENTATION LYMPHATIC TISSUES AND ORGANS DG IMMUNE SYSTEM I. Lymphatic Tissues a. Loose b. Dense c. Nodular II. Lymphatic Organs a. Thymus b. MALT Mucosa Associated Lymphoid Tissue c. Lymph node d. Spleen IMMUNE SYSTEM I. Lymphatic T...

LABORATORY ORIENTATION LYMPHATIC TISSUES AND ORGANS DG IMMUNE SYSTEM I. Lymphatic Tissues a. Loose b. Dense c. Nodular II. Lymphatic Organs a. Thymus b. MALT Mucosa Associated Lymphoid Tissue c. Lymph node d. Spleen IMMUNE SYSTEM I. Lymphatic Tissues a. Loose b. Dense c. Nodular II. Lymphatic Organs a. Thymus b. MALT Mucosa Associated Lymphoid Tissue c. Lymph node d. Spleen LYMPHATIC TISSUES I. Loose a. Esophagus b. Trachea II. Dense and Nodular a. Ileum b. Appendix ESOPHAGUS SCANNER VIEW A B Layers of Esophagus A. Mucosa C B. Submucosa C. Tunica muscularis D. Tunica adventita D ESOPHAGUS A LOW POWER B Sublayers of Mucosa: A. Lining Epithelium C B. Lamina Propria C. Muscularis mucosa  ESOPHAGUS A LOW POWER Mucosa: (A) LE: Stratified squamous non- B keratinized epithelium (B) LP: Loose Connective tissue with C scattered lymphocytes D (C) MM: smooth muscles Submucosa: Presence of Deep Esophageal glands (D) ESOPHAGUS HIGH POWER Mucosa: LE: Stratified squamous (SS) non-keratinized epithelium LP: Loose Connective tissue with scattered lymphocytes MM: smooth muscles Submucosa: Presence of Deep Esophageal glands (D) TRACHEA SCANNER VIEW A. Lining epithelium is A Pseudostratified columnar ciliated epithelium with goblet cells (PCCE with GC) B. Tracheal glands are tubuloalveolar mixed glands B located in the submucosa. C C. Trachealis muscle. It is a smooth muscle that bridges the gap between the free ends of C- D shaped cartilages. D. Tracheal cartilage TRACHEA A LOW POWER A. Lining epithelium is Pseudostratified columnar B ciliated epithelium with goblet cells (PCCE with GC) B. Lamina Propria – Loose Connective Tissue C with scattered lymphocytes C. Tracheal glands found in the submucosa D D. Tracheal (hyaline) cartilage LYMPHATIC TISSUES I. Loose a. Esophagus b. Trachea II. Dense and Nodular a. Ileum b. Appendix ILEUM SCANNER VIEW LAYERS 1.Mucosa 2.Submucosa 3.Tunica muscularis 4.Tunica adventitia ILEUM SCANNER Presence of villi, fingerlike projections in the mucosa Combination of dense and nodular LT in the LP Peyer’s patches are most numerous in the distal portion (encircled) ILEUM SCANNER VIEW Sublayers of Mucosa 1. LE: simple columnar 2. Lamina propria – Note the presence of the characteristic feature of this organ (encircled) – PEYER’S PATCHES 3. Muscularis mucosa ILEUM LOW POWER Peyer’s patches are most numerous in the distal portion (encircled) Lymphatic nodules are however present in all segments of the small intestines APPENDIX SCANNER VIEW Mucosa This segment of the large intestines or colon has the most numerous aggregates of lymphatic nodules LE: simple columnar with goblet cells LP: intestinal glands, dense and nodular LT Appendiceal crypts LYMPHATIC TISSUES I. Loose a. Esophagus b. Trachea II. Dense and Nodular a. Ileum b. Appendix  Lymphoid Nodules/ Lymphoid Follicles Compact, circumscribed aggregates of B cells A 1. Primary lymphoid nodule Aggregates of uniform cell density and staining B 2. Secondary lymphoid nodule Aggregates with larger, more euchromatic cells centrally (A) Germinal center - A central, pale staining portion of a secondary nodule (B) Mantle - Dark staining portion IMMUNE SYSTEM I. Lymphatic Tissues a. Loose b. Dense c. Nodular II. Lymphatic Organs a. Thymus b. MALT Mucosa Associated Lymphoid Tissue c. Lymph node d. Spleen THYMUS SCANNER VIEW Capsule: - Loose collagenous CT Septa (arrows) - Extensions of the capsule into the parenchyma Divides the organ into incomplete lobules with 1. Cortex 2. Medulla THYMUS SCANNER VIEW Thymus is divided into: 1. Cortex (A) A Darkly basophilic Extensive lymphoblasts aka thymocytes B A 2. Medulla (B) B Lightly stained Hassall’s corpuscles THYMUS LOW POWER Encircled structures are HASSALL’S CORPUSCLES/ THYMIC CORPSUCLES characteristic feature of thymus found in the medulla THYMUS HIGH POWER Encircled structures are HASSALL’S CORPUSCLES/ THYMIC CORPSUCLES characteristic feature of thymus found in the medulla TONSILS SCANNER VIEW Ø Partially encapsulated: dense collagenous hemi- capsule Ø Lined by: SSE, the exposed portion Ø Plenty of lymphatic nodules are seen. Ø The spaces are called tonsillar crypts. TONSILS SCANNER VIEW Ø Partially encapsulated: dense collagenous hemi- capsule Ø Lined by: SSE, the exposed portion Ø Plenty of lymphatic nodules are seen. Ø The spaces are called tonsillar crypts (arrow) TONSILS LOW POWER VIEW Note the presence of spaces called TONSILLAR CRYPTS (arrows) LYMPH NODE SCANNER VIEW LYMPH NODE SCANNER VIEW Capsule (arrow) Dense Irregular CT Trabeculae: Extensions of the capsule Underneath the capsule are spaces called subcapsular sinuses that drain lymph to the marginal sinuses. LYMPH NODE LOW POWER Capsule (A) Dense Irregular CT A Trabeculae (arrow) Extensions of the capsule Underneath the capsule are spaces called subcapsular sinuses that drain lymph to the marginal sinuses. LYMPH NODE SCANNER VIEW Layers: 1. Cortex Lymphatic nodules (LN) Primary and/or secondary nodules or follicles can be observed 2. Paracortex Lacks LNs Lymphoid tissue is rich in T cells 3. Medulla a. Medullary cords b. Medullary sinuses LYMPH NODE HIGH POWER VIEW Layers: 1. Cortex A 2. Paracortex 3. Medulla (A) - Medullary cords (B) - Medullary sinuses B SPLEEN SCANNER VIEW Capsule: Fibroelastic; DICT and smooth muscles Trabeculae: extensions of the capsule that penetrate the pulp; carry blood vessels within them (both artery and vein) SPLEEN LOW POWER Two regions: 1. Red pulp a. Splenic cords/ Billroth cords - Composed of A macrophages, and blood cells of all kinds B. Splenic sinusoids - Lined by Stave cells: elongated cells 2. White pulp a. Lymphatic nodule of the B spleen b. Central arteriole surrounded by PALS of T lymphocytes SPLEEN LOW POWER Two regions: 1. Red pulp a. Splenic cords/ Billroth cords - Composed of A macrophages, and blood cells of all kinds B. Splenic sinusoids - Lined by Stave cells: elongated cells 2. White pulp a. Lymphatic nodule of the B spleen b. Central arteriole surrounded by PALS of T lymphocytes SPLEEN WHITE PULP Lymphatic nodule of the spleen Central arteriole surrounded by PALS of T lymphocytes (arrow) SPLEEN RED PULP Splenic cords/ Billroth cords Splenic sinusoids END