# Radiation Oncology/Anatomy

* Front Page: Radiation Oncology | RTOG Trials | Randomized Trials
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

## External Resources

* Diagnostic Radiology
* Nuclear Medicine