delineation of dysphagia aspiration related structures

Delineation of Dysphagia/Aspiration-Related Structures (DARS)

Dr Rajesh BalakrishnanMD, DNB (Radiotherapy)

1

References for the Talk

• Radiotherapy and Oncology 93 (2009) 545–552• Radiotherapy and Oncology 110 (2014) 390-397

2

Prerequisites

• Good Planning CT – Good Immobilistaion setup– With Contrast imaging– 3mm Slice thickness or smaller

• Suggested the center (HU) and width (HU) values (window settings) used to delineate the OARs– Brain: C35, W100– Bone: C450, W1,600– H&N: C35, W350– Parotid: C 840 , W 370

3

• Temporal Lobes• Right Eye and Lens• Left eye and lens• Right Optic nerve• Left Optic nerve• Optic chiasm• Pituitary• Cochlea• Brainstem

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Organs at Risk (1)

• Spine• Parotid Glands• Sub Mandibular Gland• Pharyngeal Constrictors• Trachea• Brachial Plexus

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Organs at Risk (2)

OPTIC APPARATUS

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Optic/Brain – Organs at Risk

• Temporal Lobes• Right Eye and Lens• Left eye and lens• Right Optic nerve• Left Optic nerve• Optic chiasm• Pituitary• Cochlea• Brainstem

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8Radiotherapy and Oncology 110 (2014) 390–397


Odontoid Process

SALIVARY GLANDS

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Parotid GlandBoundary Explanation

Cranial External auditory canal, mastoid process

Caudal Post. part submandibular space

AnteriorMasseter m, post. border mandibular bone, medial and lateral pterygoid m.

PosteriorAnt. belly sternocleidomastoid m, lat. side post. belly of the digastric m. (posterior-medial)

Lateral Subcutaneous fat, platysma

MedialPost. belly of the digastric m, styloid process, parapharyngeal space 24

Submandibular GlandBoundary Explanation

Cranial Medial pterygoid m, mylohyoid m.

Caudal Fatty tissue

Anterior Lat. surface mylohyoid m, hyoglossus m.

Posterior Parapharyngeal space, sternocleidomastoid m.

LateralMed. surface medial pterygoid m, med. surface mandibular bone, platysma

MedialLat. surface mylohyoid m, hyoglossus m, superior and middle pharyngeal constrictor m, anterior belly of the digastric m. 25

Sublingual GlandBoundary Explanation

Cranial(Mucous membrane covering the floor of the mouth), crossing lingual septum , intrinsic tongue muscles

Caudal Ant. part mylohyoid m, geniohyoid m.

Anterior Ant. part surface mandibular bone, mylohyoid m.

Posterior Hyoglossus m.

LateralAnt. part med. surface mandibular bone, mylohyoid m.

Medial Genioglossus m. 26

Salivary Glands - Delineation

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5 Anterior belly digastric m.

6 Geniohyoid m.

10 Sternocleidomastoid m.

11 Platysma

••••• Sub Lingual Glands – Dark Blue


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5 Anterior belly digastric m.

6 Geniohyoid m.

9 Pharyngeal constrictor m.


11 Platysma



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1 Genioglossus m.

2 Mylohyoid m.

3 Hyoglossus m.


11 Platysma

15 Mandibular bone



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1 Genioglossus m.

2 Mylohyoid m.

3 Hyoglossus m.

9 Pharyngeal constrictor m.


15 Mandibular bone



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1 Genioglossus m.

2 Mylohyoid m.

3 Hyoglossus m.

4 Posterior belly digastric m.

7 Medial pterygoid m.


12 Masseter m.

13 Parapharyngeal space••••• Sub Lingual Glands – Dark Blue


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1 Genioglossus m.

2 Mylohyoid m.




12 Masseter m.

15 Mandibular bone



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12 Masseter m.



34



8 Lateral pterygoid m.


12 Masseter m.

13 Parapharyngeal space

14 Styloid process

15 Mandibular bone••••• Sub Lingual Glands – Dark Blue

Parotid – Axial and Coronal

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Submandibular – Sagittal and Coronal

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SubLingual – Sagittal and Coronal

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SOFT PALATE

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Soft PalateBoundary Explanation

CranialHard palate, nasopharyngeal mucosal space/air lumen

CaudalTongue base, palatine tonsils, oropharyngeal mucosal space/air lumen

AnteriorHard palate, tongue/tongue base, air present in oral cavity or pharyngeal lumen

PosteriorSuperior pharyngeal constrictor m, pharyngeal mucosal space/air lumen

Lateral

Pterygoid process, medial pterygoid plate, superior pharyngeal constrictor m, medial pterygoid m, parapharyngeal space, palatine tonsil, pharyngeal lumen 39

SOFT PALATE – Sagittal and Axial

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SOFT PALATE

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1 Tongue


3 Superior pharyngeal constrictor m.

4 Uvula

5 Hard palate

6 Medial pterygoid plate

7 Pharyngeal lumen


9 Pterygoid process

10 Level of the palatine tonsil.

SOFT PALATE

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1 Tongue



4 Uvula

5 Hard palate


7 Pharyngeal lumen


9 Pterygoid process


SOFT PALATE

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1 Tongue



4 Uvula

5 Hard palate


7 Pharyngeal lumen


9 Pterygoid process


SOFT PALATE

44

1 Tongue



4 Uvula

5 Hard palate


7 Pharyngeal lumen


9 Pterygoid process


SOFT PALATE

45

1 Tongue



4 Uvula

5 Hard palate


7 Pharyngeal lumen


9 Pterygoid process


SOFT PALATE

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1 Tongue



4 Uvula

5 Hard palate


7 Pharyngeal lumen


9 Pterygoid process


LIPS AND BUCCAL MUCOSA

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Inner Surface Upper LipsBoundary Explanation

CranialHard palate (lateral), anterior nasal spine (at the midline)

Caudal Lower edge upper lip

Anterior Orbicularis oris m, subcutaneous tissue/fatty skin

Posterior Teeth, maxillary bone, hard palate, tongue

Lateral Depressor anguli oris m, buccinator m, levator anguli oris m./risorius m.

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Inner Surface Lower LipsBoundary Explanation

Cranial Upper edge lower lip

CaudalLower edge teeth sockets, cranial edge mandibular body

Anterior Orbicularis oris m, subcutaneous tissue/fatty skin

Posterior Mandibular body, teeth, tongue, air (if present)

Lateral Depressor anguli oris m, buccinator m.

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Inner Surface CheeksBoundary Explanation

CranialTransition between maxillary sinus and alveolar process maxilla

Caudal Alveolar process mandible

Anterior Orbicularis oris m.

Posterior Post. edge mandibular body, post. edge maxilla

Lateral Buccinator muscle, fatty tissue

Medial Mandibular body, teeth, tongue50

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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone

7 Anterior nasal spine

8 Buccinator m

9 Levator anguli oris/risorius m

10 Alveolar process maxilla

11 Maxillary sinus

12 Depressor anguli oris m

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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone


8 Buccinator m



11 Maxillary sinus


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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone


8 Buccinator m



11 Maxillary sinus


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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone


8 Buccinator m



11 Maxillary sinus


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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone


8 Buccinator m



11 Maxillary sinus


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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone


8 Buccinator m



11 Maxillary sinus


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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone


8 Buccinator m



11 Maxillary sinus


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1 Orbicularis oris

2 Tongue

3 Fatty tissue

4 Hard palate

5 Mandibular body

6 Maxillary bone


8 Buccinator m



11 Maxillary sinus


PHARYNGEAL CONSTRICTORS

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Superior Constrictor MuscleBoundary Explanation

Cranial Occipital condyle

Caudal Superior Edge of Hyoid Bone

Anterior Anterior edge of pterygoid muscle

Posterior Longus Capitis muscle

Lateral Palatine Tonsil or Parapharyngeal space

Medial Pharynx

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Middle Constrictor MuscleBoundary Explanation

Cranial 0.5 cm Above Hyoid bone

Caudal Inferior Edge of Hyoid Bone

Anterior Oropharynx, Lateral edge of Hyoid bone

Posterior Longus Capitis muscle

Lateral Palatine Tonsil or Parapharyngeal space

Medial Pharynx

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Inferior Constrictor MuscleBoundary Explanation

Cranial Inferior edge of Hyoid bone

Caudal Esophagus

Anterior Arytenoid, First Tracheal ring

Posterior Longus Capitis muscle, Anterior Vertebral body

Lateral Parapharyngeal space, Lateral edge of Thyroid

Medial Pharynx

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Dose ConstraintsConstrictors Mean Dose < 50 Gy QUANTEC

Lips Mean Dose <20 GyFor parotid tumor: Max < 30GyFor SM tumor : Max < 45 Gy

RTOG 1008

Oral Cavity (Non OC tumor) Mean < 30 Gy ; No hot spots > 60 Gy

RTOG 0920

Oral Cavity (OC tumor) Mean < 50 Gy ; V55 < 1 %Max dose -65 Gy

RTOG 0920

TMJ / Mandible Max 70 Gy RTOG 0615

Larynx Mean < 44 Gy ; V50 < 33 %Max dose - 63 -66Gy

QUANTEC

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Dose Constraints

Parotid Glands Mean < 25 Gy (Both glands)Mean < 20 Gy (Single gland)

QUANTEC

Submandibular Glands Mean < 35 Gy QUANTEC

Thyroid V26 < 20 % JHH guidelines

Cochlea Ipsilateral Max <50GyMean < 45 Gy

RTOG 1016QUANTEC

Eyes Max <30 Gy RTOG 1008

Lens Max : < 2.5 Gy RTOG 1008

Optic nerve/ Chiasm Max < 30 Gy RTOG 1008

Brainstem Entire Brainstem – < 54 GyV59Gy < 1-10cc

QUANTEC

Spinal cord Max 50 Gy QUANTEC

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Conclusion

• Correct Contouring of OARs is as important to contouring of Target.

• Whenever in doubt please refer to atlases available online.

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delineation of dysphagia aspiration related structures

Health & Medicine

talk radiotherapy

surface mylohyoid

surface mandibular bone

surface medial pterygoid

w100 bone

posterior hyoglossus

spine parotid glands

risk temporal lobes