Radiation Oncology/Anatomy

See also: Contouring

This page is for Anatomy Pearls useful for radiation oncology. Suitable examples include radiographic landmarks, location of lymph node groups, and lymph drainage patterns.

Anatomy atlases

• HeadNeckBrainSpine Neuroradiology
• Gray's Anatomy @ Bartleby.com
• Basic Anatomy @ Dartmouth
• Wesley Norman Anatomists
• AnatomyAtlases.org
• Radiology Assistant
• Cross-sectional nodal atlas, 1999 (Ohio State) - PMID 10352611 Full text — "Cross-sectional nodal atlas: a tool for the definition of clinical target volumes in three-dimensional radiation therapy planning." Martinez-Monge R et al. Radiology. 1999 Jun;211(3):815-28.
  • Atlas of everything (H&N, lung, GI, GU, Gyn) on CT images with nodal regions shaded.
• Wayne State University link
  • Brain: MRI (Sagittal, Coronal, Axial)
  • Upper Abdomen: CT
  • Thorax: CT
  • Pelvis + Upper Thigh: CT

Dissections

• SUNY Downstate

Vertebral Levels

D means disc below level
Categorized:

• Vocal Cord —> C5
• Cricoid —> C6
• Start of trachea —> C6-C7
• Thyroid gland —> C7
• Lung apex —> T1
• Origin SVC —> T3
• AO arch —> T4/DT3
• Carina —> T5
  • 25 cm from the incisors
• Liver
  • Upper level: T7-8

• Suprasternal Notch —> T3
• Manubrium —> T4
• Angle of louis —> T5
• Xiphoid Process —> T10

• Ant costodiaphragm —> T10
• Post costodiaphragm —> L3

• GEJ —> T10/T11 ( 2-3cm to left of midline )
  • 40cm from incisors
• Spleen —> T10-T11 ( 5cm left to midline )
• Pancreas body —> L1
• Cysterna chili —> L1-L2
• Umbilicus —> L4
  • If standing and in infants —> lower
• Gallbladder —> at 9th rib; right lat border of rectus abdomens ( transpyloric plane )
• Start of large bowel ( Cecum ) —> L4
  • Ascending Colon : 15cm
  • Descending Colon : 25cm
• Rectum —>
  • Starts : S3
  • Ends : 4cm from anus

• R Kidney hilum —> L2
• L Kidney hilum —> L1

• Para-AO nodes —> T12-L4
• Common Iliac nodes —> L4 ( Bifurcation of AO )
• Bifurcation of common iliac —> L5-S1

Uncategorized:

• Hyoid Bone C4
• Right Lung T1-T11
• Left Lung T1-DT10
• Suprasternal Notch T3
• Aortic arch DT3
• Origin SVC T3
• Bifurcation of Trachea T5
• SVC Heart junction T7
• IVC Heart T9
• Apex of Heart T10
• Fundus stomach T10
• Spleen T10-L1
• GE Junction T11
• Xiphoid Apex DT11
• Left Kidney DT11-L3
• Right Adrenal T11-L1
• Left Adrenal T12-L1
• Superior duodenum DT12
• Colon splenic Flexure T12
• Pancreas Body T12
• Right lobe of Liver T9-DL3
• Right Kidney T12-L3
• Duodenal Jejeunal Flexure L1
• Stomach pylorus L1
• Colon hepatic flexure L2
• Bottom of gallbladder L2
• Aortic bifurcation L4
• Iliac Crest L4
• Umbilicus L4
• Ileo Cecal Valve L5
• Base of Appendix L5
• IVC origin L5
• Lower border of Cecum DS2

Clinical Syndromes with CN Palsy

• Please see the Clinical Syndromes with CN Palsy page

Head & Neck

• Please see the H&N anatomy page

Regional breast lymph nodes

• Please see the axilla RT technique section

Supraclavicular

Brachial plexus:

• Please see the Brachial plexus section
• Also see the section on this page Radiation_Oncology/Anatomy#Thorax

Thorax

See also: Radiation Oncology/Thorax/Anatomy (Lung lymph node stations)

Abdomen

Vessels

In order, superior to inferior:

• Celiac artery

  At T12 (75%) or L1 (25%)

• SMA
• Renal arteries/veins
• Ovarian/testicular vein - Right side, drains into IVC 1 cm below R renal vein. Left side, drains into L renal vein lateral to the aorta.
• Ovarian/testicular arteries - 5 to 6 cm above aortic bifurcation
• IMA - 3 to 4 cm above aortic bifurcation

Lymphatics

• Pancreaticoduodenal nodes - lie in C-loop of duodenum

• Paraaortic lymph nodes (may also be called para-aortic, periaortic, or peri-aortic) - located adjacent to aorta, anterior to lumbar spine, extending bilaterally to the medial margins of the psoas major muscles, up to diaphragmatic crura.

  For a paraaortic lymph node dissection, the surgeon usually dissects from aortic bifurcation up to SMA or renal veins.

CT Atlas

• Baylor; 2007 PMID 17959923 -- "Learning the nodal stations in the abdomen." (Moron FE, Br J Radiol. 2007 Oct;80(958):841-8.)

Pelvic lymph nodes

• Beth Israel, 2010 - PMID 20032141 -- "Lymphatic metastases from pelvic tumors: anatomic classification, characterization, and staging." (McMahon CJ, Radiology. 2010 Jan;254(1):31-46.)
  • Comment: shows subdivisions of lymph node groups. Normal node size cutoffs.
• Park (MDACC), 1994 - PMID 7855343 — "Pathways of nodal metastasis from pelvic tumors: CT demonstration." (Park JM, Radiographics. 1994 Nov;14(6):1309-21.)

Prostate

• Please see Radiation_Oncology/Prostate/Anatomy

Skin LN drainage

• Auckland; 2007 (New Zealand) PMID 17643351 -- "Three-dimensional visualisation of lymphatic drainage patterns in patients with cutaneous melanoma." (Reynolds HM, Lancet Oncol. 2007 Sep;8(9):806-12.)
  • Heat maps based on 5239 SLN analyses of cutaneous melanoma patients
  • Conclusion: Sappey's lines not effective

Pterygopalatine ganglion

• Suspended from V2 branch of trigeminal (CNV) nerve
• Parasympathetic input from superior salivary nucleus in brain stem travel via facial nerve (CNVII) to greater superficial petrosal nerve
• Sympathetic fibers from carotid plexus travel via deep petrosal nerve
• The deep petrosal nerve and greater superficial petrosal nerves join to form the vidian nerve, which passes through (sympathetic fibers)/into (parasympathetic fibers) the pterygopalatine nucleus
• Postganglionic parasympathetic fibers and passing-through sympathetic fibers travel through trigeminal nerve to lacrimal gland and nasal/oral mucosa