lymphatics , examination of lymph nodes.

Anatomy, physiology of lymphnodes and examination of lymphnodes and diseases involving various lymphnodes
investigation &
diagnosis
management

1. GOOD AFTERNOON

2. LYMPH NODE

3. LYMPHOID SYSTEM The lymphoid system is a parallel circulatory system that exists along with cardiovascular system in which lymph flows. Lymphatic system Lymphoid organs Lymphatic duct system Lymph

4. Lymphatic duct system It includes lymphatic capillaries, lymphatic vessels & lymphatic duct. Lymphatic duct are of 2 types Right lymphatic duct Left lymphatic duct or Thoracic duct Structure of lymphatic duct The walls of lymphatic duct consists of the wall of lymphatic ducts have same three layers, ie tunica adventitia, tunica media and tunica intima. Lumen of lymphatic duct contains valves which are numerous and closely packed than veins.

5. Right lymphatic duct It is 1.2cm long. 3 lymphatic trunks drain into Right lymphatic duct – Right Jugular trunk-drains Right side of head & neck Right subclavian trunk- Right upper limb Right broncho mediastinal trunk-Rt side of thorax, Rt lung, Rt side of heart , & part of liver Right lymphatic duct joins the venous system at the junction of Right Sub clavian & Right internal jugular veins

6. Left lymphatic duct Also known as Thoracic duct. It is 38-45 cm long B egins as a dilation called cisterna chyli anterior to 2nd lumber vertebra. Main duct for return of lymph to blood. Receives lymph from left side of head, neck, Left upper limb, chest & entire body inferior to ribs. Joins the venous system at the junction of Left Sub clavian vein.

7. Lymphatic capillaries Microscopically they are blind-ended lymph vessels which begin in the intercellular spaces. These are different from blood capillaries in following respect: 1. Begin blindly in intercellular spaces 2. Have bigger lumen which is less regular 3. Are permeable to bigger molecules . L ymph capillaries are absent in Epidermis , Hair , Nails, Cornea, Articular cartilage, Brain, spinal cord, splenic pulp.

8. Lymphatic vessel According to location lymph vessels are divided into two types:- 1. Superficial lymph vessels 2. Deep lymph vessels. Beaded appearance. Flow of lymph in lymphatic vessel is unidirectional.

9. Lymph Lymph is a clear watery fluid found in the lymphatic vessels. It appears white in the thoracic duct after a fatty meal. Composition Water Solids Proteins Lipids Clotting factors Cells Lymphocytes Plasma cells Macrophages Platelets About 30lt of fluid passes from arterial end of capillaries into intercellular space every day out of that 3lt of fluid consisting of macromolecules is absorbed by lymph capillaries.

10. Formation of lymph Fluid from plasma enter tissue –tissue fluid Tissue fluid enters lymphatic vessels-lymph Factors influencing formation of lymph Increase in hydrostatic pressure-Hypertension, venous obstruction Increase in the capillary surface Increase in the capillary permeability-Hypoxia, ADP, Bradykinin

11. Lymphatic Capillary Lymphatic Vessel Lymph Node Lymphatic Vessel Lymphatic Trunk Collecting Duct Subclavian Vein Flow of lymph:

12. Lymphoid tissue Lymphoid tissue may be broadly classified as diffuse lymphoid tissue and dense lymphoid tissue. Diffuse lymphoid tissue: Consists of lymphocytes & plasma cells in the mucosa of large intestine, trachea, bronchi & urinary tract. Dense lymphoid tissue: Consists of aggregation of lymphocytes arranged in the form of nodules. It is divided into Discrete lymphoid organs Mucosa associated lymphoid tissue 1.BALT 2.GALT

13. PRIMARY LYMPHOID ORGANS SECONDARY LYMPHOID ORGANS  Central lymphoid organs. Peripheral lymphoid organs. Primary lymphoid organs are the sites where Leukocytes (WBCs) are generated. Secondary lymphoid organs are the sites where Adaptive immune responses (Acquired immunity) are initiated. It includes: (A) Bone marrow and (B) Thymus. It includes: (A) Spleen, (B) Lymph Node and (C) MALT. The Lymphoid stem cells proliferate (rapid increase), differentiate and mature. The Lymphoid stem cells becomes functional.  Contains either B – cell or T – cell. Contains both B – cell or T – cell. Site of Maturation for T & B cells. Site of Cell function for T & B cells. Differentiation of Lymphocytes is taken place in Primary lymphoid organs. Interaction of immune cells with each other and antigen processing are taken place in Secondary lymphoid organs. Decrease in size and strength with age. Increase in size with age.

14. Thymus Thymus is central lymphoid organ. It is large at the time of birth (70 g) but with age, the size keep on reducing and becomes very small by attaining puberty (3 g).   Each Lobe is surrounded by a Capsule and is divided into Lobules, which are separated from each other by strands of Connective tissue called Trabeculae. Responsible for development of immune system of the body. The main function of the Thymus is to release Thymosin hormone that will stimulate the maturation of T - cells. Essential for growth & development of other lymphatic systems.

15. Bursa Fetal liver & bone marrow act as equivalent of avian bursa fabricius. ‘B’ lymphocytes are produced by liver and bone marrow in fetal stage. Bone marrow i s the soft, flexible connective tissue present within the bone cavities. Bone marrow is of 2 types :  Red marrow and Yellow marrow. RED BONE MARROW YELLOW BONE MARROW  Also known as Myeloid tissue.  Also known as Fatty tissue.  Hematopoietic in nature and produces RBC, WBC & Platelets. Multipotent Stromal in nature and produces Fat, Cartilage and Bone It’s red color is from the hemoglobin . It’s yellow color is from the carotenoids in the fat droplets.  High Vascular supply Poor Vascular supply Function - Helps to remove old cells from circulation.  Function - yellow marrow can be converted to red marrow in order to produce more blood cells.

16. Spleen The spleen is an organ located in the left side of the Abdominal cavity under the Diaphragm, the muscular partition between the Abdomen and the Chest. Spleen v aries in size and shape between people, but it’s commonly Ovoid shaped and Reddish brown in color. The spleen, in healthy adult humans, is approximately 7 cm (2.8 in) to 14 cm (5.5 in) in length. It usually weighs between 150 g and 200 g. It acts as hematopoietic organ in fetal life where as grave yard in postnatal life .

17. Microscopic features The spleen is surrounded by a Capsule that extends a number of projections (Trabeculae) into the interior to form a compartmentalized structure.  The compartments are of two types, the ( i ) Red pulp & (ii)White pulp, which are separated by a diffuse marginal zone.  Red pulp consists of a network of sinusoids populated by Macrophages and numerous RBCs and few Lymphocytes White pulp surrounds the branches of the Splenic artery, forming a Periarteriolar lymphoid sheath (PALS) populated mainly by T – lymphocyte Primary lymphoid follicles - Rich in B - cells and some of them contain Germinal centers.

18. MALT Mucosal l ining the digestive, respiratory, and urogenital systems have a combined surface area of about 400 m2 and are the major sites of entry for most pathogens. These vulnerable membrane surfaces are defended by a group of organized lymphoid tissues mentioned earlier and known collectively as Mucosal-associated lymphoid tissue (MALT). MALT can be further classified as Gut-associated lymphoid tissue (GALT) or Bronchus-associated lymphoid tissue (BALT). The Tonsils, Appendix and Peyer’s patches are representative of lymphoid tissue found in and around mucosal epithelia.

19. TONSILS Near the junction of oral cavity around the pharynx there are a number of collection of lymphoid tissue termed as tonsils. Among them palatine tonsils are the largest which are located on either side of oropharyngeal isthmus. Microscopic features Palatine tonsil is lined by stratified squamous epithelium. Deep crypts are seen where epithelium extends into the substance of tonsil(often called as tonsillar crypts). Waldeyer’s tonsillar ring includes 1. Adenoid tonsil 2. Two tubal tonsils 3. Two palatine tonsils 4. Lingual tonsil .

20. Appendix It is a blind  ended tube connected to the Cecum. The human appendix averages 9 cm in length but can range from 2 to 20 cm. The diameter of the appendix is usually between 7 and 8 mm. Functions of Appendix – 1) Maintaining Gut flora, 2) Important component of Mucosal immune function and 3) Storehouse for good bacteria

21. Peyer’s patches These are small masses of lymphatic tissue found throughout the Ileum region of the Small intestine. Peyer’s patches are roughly egg-shaped lymphatic tissue nodules that are similar to lymph nodes in structure, except that they are not surrounded by a connective tissue capsule. Peyer’s patches play an important role in trapping antigens from pathogens and destroying them.

22. Lymph nodes They are a group of small, bean-shaped organs (2.6 cm in length) found mainly in the neck and trunk of the human body. They play vital roles in the filtration of antigens and debris from Lymph (circulating colorless watery fluid) and in the generation of immune responses to pathogens. Microscopic features A thin capsule surrounds the lymph node which opens into trabeculae The clear space present beneath the capsule is called as subcapsular sinus Outer zone called as cortex .It contains lymphatic follicles ;each follicle contains geminal center. Inner zone called as medulla. It contains fewer lymphocytes (in the form of branching cords), hence stains lighter.

23. Lymph nodes in the head and neck region can be grouped into: Superficial nodes B) Deep nodes (1)Submental (1) The jugulodigastric node (upper deep cervical) (2)Submandibular (2) The juguloomohyoid node(lower deep cervical) (3)buccal and mandibular (4)Preauricular (parotid) (5)Postauricular (mastoid) (6)Occipital (7)Anterior cervical (8)Superficial cervical nodes.

24. Submental nodes These are three or four nodes situated across the midline below the chin in the submental triangle . Central part of the lower lip, floor of the mouth, tip of the tongue Method of palpation: They are palpated under the chin The patient is instructed to bend his/her neck slightly forward so that the muscles and fascia in that regions relax. Fingers of both hands can be placed just below the chin, under the lower border of mandible and the lymph nodes should be tried to be cupped with fingers.

25. Submandibular nodes These nodes are usually three in number & situated in the submandibular triangle in contact with the surface of the submandibular salivary gland and within its substance . They drain Cheek, tongue, whole of the upper lip, outer part of the lower lip, gums, angle of mouth, side of nose, inner angle of the eye Method of palpation : They are palpated at the lower border of the mandible approximately at the angle of the mandible. The patient is instructed to passively flex the neck towards the side that is being examined. The fingers of the palpating hand should be kept together to prevent the nodes from slipping in between them.

26. Preauricular nodes Also known as Parotid Lymph Nodes. The parotid lymph nodes lie partly in the superficial fascia and partly deep to the deep fascia over the parotid gland. They drain: The temple, the side of the scalp, the lateral surface of the auricle, the external acoustic meatus, the middle car, the parotid gland, the upper part of the cheek, parts of the eyelids, and the orbit. Method of palpation : Bilateral palpation of the pre auricular lymph nodes utilizing the mandibular ramus and coronoid process as a firm surface against which to palpate. They are palpated anterior to the tragus of the ear.

27. Post auricular nodes Also called as Mastoid Lymph Nodes . They lie on the mastoid process superficial to the sternocleidomastoid and deep to the auricularis posterior. They drain a strip of scalp just above and behind the auricle, the upper half of the medial surface and margin of the auricle, and the posterior wall of the external acoustic meatus. Method of palpation : They are palpated behind t he ear, on the mastoid process.

28. Occipital nodes The occipital nodes lie at the apex of the posterior triangle superficial to the attachment of trapezius. They drain the occipital region of scalp. Method of palpation : Palpated at the base/lower border of skull.

29. Superficial cervical nodes Superficial cervical lymphnodes includes pretracheal & prelaryngeal lymphnodes. Prelaryngeal nodes are located on cricothyroid membrane. Pretracheal lymphnodes are located anterior to trachea below the isthmus of the thyroid gland. They drain the larynx ,isthmus of thyroid & trachea. Method of palpation : Palpated superficial to upper part of sternocleidomastoid along it’s anterior border.

30. Anterior cervical nodes They are situated along the anterior jugular vein. One member of this group lies frequently in the suprasternal space(suprasternal nodes). They are extensions of submental lymphnodes. Method of palpation : Palpated superficial to upper part of sternocleidomastoid along it’s border.

31. Buccal & Mandibular nodes The buccal nodes lie on the buccinator muscle. They drain the part of the cheek and lower eyelid. The mandibular lymphnodes are located on lower part of mandible near the anteroinferior border of the masseter. It lies in close relation with mandibular branch of facial nerve.

32. J ugulodigastric node It lies below the posterior belly of the digastric, between the angle of the mandible and the anterior border of the sternocleidomastoid It is the main node draining the tonsil. J uguloomohyoid node It lies just above the intermediate tendon of the omohyoid, under cover of the posterior border of the sternocleidomastoid. It is the main lymph node of the tongue. Palpated in the posterior triangle of the neck close to the anterior border of trapezius. Examination of the lymphnode is accomplished by asking the patient to turn the neck away from the side to be examined.

33. General Examination

34.   General examination : History  Age Duration Group first affected Pain F ever P rimary focus L oss of appetite Wt. Loss P ressure effects

35.   A ge : In young children, common cause of lymph node enlargement is due to viral etiology, Tuberculosis  and syphilis , primary malignant lymphomas affect young age . Adults: TB lymphadenitis is common in this age group. Middle age: Hodgkin’s lymphoma Old age: Metastasis from known and unknown primary Duration: Short: In cases of pyogenic infections, e.g. in acute tonsillitis, enlargement of tonsillar node—jugulodigastric node may be seen. Long: In tuberculosis and metastasis (secondaries), the duration is long—may be a few month Speed of growth: Short duration and rapid growth usually suggest metastasis in lymph nodes. Slow growth suggests tuberculosis or even lymphomas.

36. Pain: Painful-Acute and chronic infection Painless - syphilis , primary malignant lymphomas and secondary carcinoma. Fever: Mild fever with evening rise, sometimes with chills suggests tuberculosis. Remittent bouts of intermittent fever suggest lymphoma Fever with multiple nodes and pain may be a feature of infectious mononucleosis . Periodic fever in filaria (once in month) Group affected first : C ervical group affects first in Hodgkin’s disease & tuberculosis where as inguinal lymphnode affects first in filariasis .

37.   Loss of appetite & wt : Incase of malignant lymphadenopathies . Past history : E nlargement of epitrochlear and suboccipital group of lymphnodes may be enlarged in secondary stage of syphilis. Family history : Sometimes history of TB in families .

38. General Physical Examination

39. Pallor : It suggests, chronic disease such as tuberculosis or malignancy. Jaundice : It can be seen in late cases of lymphoma with involvement of liver. Skin rashes : Coppery red skin rashes with lymphadenopathy may be an indication of secondary syphilis (rare nowadays). Dilated veins over the chest and congestion of the face suggest superior venacaval obstruction – may be caused by mediastinal lymph nodes, suspect lymphoma. Bony pains with lymph nodes in the neck may be due to leukaemia or lymphoma or due to disseminated malignancy. Unilateral pedal oedema can be caused by enlarged iliac nodes—may be malignant or lymphoma.

40. Local Examination

41. Local examination Inspection Palpation Consistency F ixity to surrounding structures D rainage area Number Position Size Skin overlying swelling Pressure effects

42. Size: When the size is variable describe the largest one and smallest one and mention they vary from, e.g. 3 cm to 1 cm. Surface: Like any other swelling describe them, e.g. smooth, isolated enlargement of lymph node or cold abscess (tubercular), nodular in lymphoma or secondaries or may be uneven as in secondaries.

43. Number :

44. Position & Swelling:

45. SKIN OVER THE SWELLING : Skin over Tuberculous lymphadenitis and cold abscess remains “cold” in true sense till they reach a point of bursting when skin becomes red and glossy.   I ncase of growing lymphosarcoma skin becomes tense, shining , with dilated subcutaneous veins. Red: Inflammatory—lymphadenitis Yellowish : Inflammatory with formation of pus. Sinus : This is due to tuberculosis. Describe the discharge also in such cases. Sinus in the groin can be also due to lymphogranuloma inguinale. Tethering of skin or dimpling or peau d’ orange means skin is infiltrated by the underlying disease and it is most likely secondaries or metastasis. Fungating ulcer over a lymph node mass is typical of late cases of secondaries Dilated veins over the skin reflects increased vascularity, usually seen in secondaries.

46. PRESSURE EFFECTS: Dysphagia may occur when esophagus is pressured. Oedema & swelling of upper limb- enlargement of axillary lymph nodes. Oedema & swelling of lower limb- enlargement of inguinal lymph nodes. Swelling & venous engorgement of face and neck may occur due to pressure effect of lymph nodes at the root of the neck. H ypoglossal nerve m ay be involved from enlarged upper group of cervical lymphnodes due to hodgkin’s disease or secondary carcinoma.

47. Consistency : Elastic & rubbery -Hodgkin’s disease Firm, discrete – syphilis, TB lymphadenitis Shotty nodes- viral etiology Stony hard-secondary carcinoma Matted- Acute lymphadenitis ,Metastatic Carcinoma Tuberculosis   Fixity to underlying structure: The enlarged lymphnode should be carefully palpated to know if they are fixed to; Skin , deep fascia , muscles , vessels ,nerves E.g. Any primary malignant growth of lymph nodes like lymphosarcoma , reticulosarcoma , histosarcoma or secondary carcinoma fixed to surrounding structures- first to deep fascia & underlying muscle followed by adjoining structures and ultimately overlying skin.

48. Acute laryngitis: The nodes are tender, soft. Papillary carcinoma of thyroid: The nodes are firm without matting, with or without evidence of thyroid nodule. Carcinoma of the larynx: The nodes are hard in consistency. Tuberculosis: Matted submental nodes, firm in consistency, with enlarged upper deep cervical lymph nodes, with or without evening rise of temperature are suggestive of tuberculosis. Non-Hodgkin’s lymphoma can present with submental nodes along with other lymph nodes in the horizontal group of nodes such as submandibular, upper deep cervical, pre-auricular, postauricular and occipital lymph nodes (external Waldeyer’s ring). Nodes are firm or rubbery, discrete without matting . Secondaries in the submental lymph nodes can arise from carcinoma of the tip of the tongue, floor of the mouth, central portion of the lower lip. The nodes are hard in consistency and sometimes, fixed . Size :Nodes are generally considered normal upto 1 cm in diameter. However, epitrochlear nodes larger than 0.5cm and inguinal nodes larger than 1.5 cm are considered as abnormal.

49. Lymphnode status in various conditions

50. Localised acute conditions Bacterial-acute periapical access, pericoronitis , cats scratch disease, In case of acute pericoronal abscess& pericoronitis lymphadenopathy of 2 wks duration is seen Lymph nodes will be Tender, Soft , Elastic , Movable ,difficult to hold at one place The most commonly involved lymph nodes in decreasing order of frequency are the submandibular, upper cervical, submental, occipital, and lower cervical nodes. Cat scratch disease is a lymphocutaneous syndrome characterized by regional lymphadenitis associated with a characteristic skin lesion at the site of inoculation. The most common sites of lymphadenopathy are the axilla (52%) and the neck (28%).

51. Viral-Mumps ,measles ,rubella, hepatitis, chicken pox, infectious mono nucleosis , cytomegalovirus Cervical lymphadenop athy is a common feature of many viral infections. Involved nodes are usually bilateral lymph nodes in the anterior triangle of the neck, multiple, small, firm and tender, without warmth or erythema of the overlying skin. Rubella almost always presents with a maculopapular rash and characteristic lymphadenopathy of the posterior cervical triangle. In case of Infectious mononucleosis symmetric involvement of the posterior cervical nodes more than the anterior cervical. Nodes may be large and kidney-shaped Cervical adenopathy may be severe enough to cause upper airway compromise.

52. Localised chronic conditions Lymph nodes will be Non t ender, hard , firm , Movable ,no local rise of temperature and with smooth surface. Syphilis –There is generalized enlargement of superficial node. Most characteristically there is enlargement of epitrochlear & suboccipital groups. Firm in feel, discrete, shotty and not tender. Sarcoidosis t he most common physical finding in children with this disease is peripheral lymphadenopathy. Involved cervical nodes are usually bilateral, discrete, firm, and rubbery. Supraclavicular nodes become involved in more than 80% of patients . Tuberculous lymphadenitis most frequently involves the cervical lymph nodes followed in frequency by mediastinal, axillary, mesenteric, hepatic portal and inguinal lymph nodes Cervical nodes in the submandibular region are most commonly affected in children

53. Jones & campbell classification of peripheral TB lymphadenopathhy

54. Generalised chronic conditions HIV -The most frequently involved sites are the posterior and anterior cervical, submandibular, occipital. and axillary nodes.   Hodgkin's lymphoma -The most  common sites of initial presentation are the cervical and supraclavicular nodes (70% to 75%) or the axillary and mediastinal nodes (5% to 10% each). Lymph nodes are ovoid, smooth, dicrete , solid, firm & rubbery in consistency & are non tender. Non Hodgkin's Lymphoma has a more frequent involvement of multiple peripheral nodes compared to HL which often remains localized to one group of nodes .

55. Acute lymphocytic leukemia leukemia can occur at any age, but ALL is commonly found in children. Infiltration of organs and tissues by leukemic cells causes lymphadenopathy, hepatomegaly, and splenomegaly. Chronic lymphocytic leukemia cervical  lymphadenopathy and tonsillar enlargement are frequent head and neck signs of CLL. Lymph nodes-generalised, painless, dicrete , firm, movable, Toxoplasmosis: Generalized lymphadenopathy with firm, tender enlargement of the cervical nodes. Fever, malaise, maculopapular rash, sore throat, myalgia, and headache

56. Investigations Complete blood picture Nodal biopsy Fine needle aspiration cytology CT scan MRI USG SPECT PET Lymphangioscintigraphy

57. Complete blood count (CBC) with differential would be helpful to detect cases caused by infectious mononucleosis, leukemia , or lymphoma. Lymphocytosis can be seen in leukemia , autoimmune disorders, Epstein Bar virus, cytomegalovirus & tuberculosis Neutrophil leukocytosis is often seen in severe infections. Neutropenia and thrombocytopenia may be useful in diagnosing systemic illnesses. ESR is found in tuberculosis, secondary carcinoma, lymphosarcoma  Orthopantomogram for imaging calcifications in lymph nodes Calcified lymph nodes commonly involved s ubmandibular and cervical nodes.

58. Positron emission tomography it is  a functional imaging that can detect metastasis lesion by pin pointing regions of high metabolism. It is better for assessing metastasis to lymph node that appear morphologically normal. Fine needle aspiration cytology it  is a safe, simple and cost-effective technique that provides rapid information and does not require a general anesthetic agent. ULTRASONOGRAPHY GUIDED FNAC- Gives more precise information than does blinded FNAC because it guides the needle to the most suspicious area of lymph nodes.

59. L ymphangiography used in cases  of lymphoedema, lymph node enlargement, sites of metastasis in carcinoma as well as malignant melanoma Radiopaque dye( lipiodol) is inserted into the localised lymph node and after that x- ray is taken. Soap bubble appearance- hodgkin’s disease Sun burst appearance- reticulosarcoma Nodular pattern- lymphosarcoma Irregular filling defect- malignancy

60. Criteria Benign Malignant Margins Sharp Irregular & blurred Shape Oval or elongated Round masses Hilum Present Absent Flow Absent Present Ultrasonography criteria

61. Levels of lymphnodes The latest classification has been created by the American Joint Committee on Cancer and the American Academy of Otolaryngology Level I : all nodes above hyoid bone, below mylohyoid muscle, and anterior to posterior edge of submandibular gland . Level IA : all nodes between medial margins of anterior digastric muscles, above hyoid bone, below mylohyoid muscle Level IB : all nodes below mylohyoid muscle, above hyoid bone, posterior and lateral to medial anterior digastric muscle and anterior to submandibular gland Level II: all nodes below skull base at jugular fossa to hyoid bone, anterior to posterior edge of sternocleidomastoid muscle and posterior to submandibular gland.

62. Level IIA : all nodes that lie posterior to internal jugular vein and are in separable from the vein or lie anterior, lateral or medial to the vein Level II B : all nodes that lie posterior to internal jugular vein and have a fat plane separating the nodes and the vein Level III : all nodes between hyoid bone and cricoid cartilage arch and anterior to posterior sternocleidomastoid muscle, and lateral to the internal carotid artery Level IV : all nodes between cricoid cartilage arch and clavicle, anterior to posterior sternocleidomastoid muscle and posterolateral to anterior scalene muscle and lateral to common carotid artery

63. Level V : all nodes from skull base posterior down to posterior border of sternocleidomastoid muscle to level of clavicle, anterior to trapezius muscle Level VA : all nodes between skull base and cricoid cartilage arch, behind posterior edge of sternocleidomastoid muscle Level VB :all nodes between cricoid cartilage arch and clavicle, behind sternocleidomastoid muscle Level VI : all nodes inferior to hyoid bone and above top of manubrium, between medial margins of bilateral common carotid and internal carotid arteries Level VII - all nodes behind the manubrium between medial margins of common carotid arteries bilaterally, extending inferiorly to level of innominate vein