C. Douglas Phillips, MD FACR Director of Head and Neck Imaging Weill Cornell Medical Center NewYork Presbyterian Hospital

Transcription

1 C. Douglas Phillips, MD FACR Director of Head and Neck Imaging Weill Cornell Medical Center NewYork Presbyterian Hospital

2 Objectives Review basics of head and neck imaging Discuss our spatial approach to head and neck imaging Describe appearance of tumors and normal and abnormal lymph nodes Review some basic of imaging pitfalls and limitations for CT and MR

3 CT or MR? Basic question is always same: What information do we hope to gain? Presence or absence of tumor Presence or absence of nodal disease Extent of neoplasm Our tools in this era CT MR PET and/or PET CT (PET MR)

4 Basics of H&N Imaging Use easiest, most reliable and reproducible technique Know patient s limitations CT usually wins Quick, accessible, inexpensive, reproducible, reliable MR may provide additional/confirmatory evidence and may be more sensitive for some disease or disease spread

5 Spatial Approach to H&N Imaging Cross sectional imaging revolutionized our approach to diagnoses Segmentation of anatomic regions by layers of deep cervical fascia Other anatomic divisions still of importance, but spatial approach narrows differential

6 Traditional Anatomic Regions Nasopharynx Oropharynx Oral cavity Hypopharynx Larynx Suprahyoid and infrahyoid neck Sinonasal cavity

7 Spatial approach: Ideal for cross sectional imaging Traditional thinking

8 Spatial Approach Pharyngeal mucosal space Carotid space Parapharyngeal space Masticator space Parotid space Buccal space Prevertebral, perivertebral space Retropharyngeal space

9 CT of H&N Tumors Lesions depicted by 2 major mechanisms Distortion of normal anatomy (morphology) Differential enhancement Typical SCCa appearance Combination of infiltrative and exophytic mass Heterogeneous enhancement Uniform enhancement is atypical, and suggests other diagnoses

10 Oral Tongue SCCa with Bilateral Nodal Disease

11 MR of H&N Tumors Similar depiction to CT, but with key advantage of MR in depicting signal changes of tumor Typical SCCa appearance Hypointense but heterogeneous on T2 Hypointense on T1 Other characteristics (mass and enhancement) as seen on CT

12 T2 T2 T1 T1 C+

13 CT of Nodal Disease Three key elements of identifying pathologic lymph nodes Size Multiple systems are utilized Levels 1 and 2 > 1.5 cm axial diameter All other internal jugular chain nodes > 1 cm Retropharyngeal nodes >5 mm Enhancement characteristics Evidence of extracapsular disease (capsular penetration)

14 MR of Nodal Disease System is not as well studied Size as per CT criteria Enhancement is poorly understood Normal nodes may heterogeneously enhance Correlate non enhancing areas with T2 signal Central nodal T2 hyperintensity Extracapsular disease often overestimated

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16 IB IB IIA IIA

17 IB IB IIA IIB IIA IIB

18 Level III Nodes

19 Level IV Nodes

20 IB IB IIA IIB IIA IIB V V

21 Pathologic Level V Node

22 Level VI Node

23 Pathologic Level VI Node

24 PET CT Adds dimension of physiologic information ( molecular imaging ) Metabolic activity of tissue on standardized scale SUV or standardized uptake value Many use cut off of 2.5 for malignancy Can be much higher in metabolically active muscles and some other tissues NOT A BE ALL, END ALL VALUE

25 SCCa Oral Tongue

26 Residual Disease Following Chemo RT

27 SCCa of Tongue: Less Significance of Artifact

28 PET CT in H&N Cancer Has proven useful in most SCCa initial evaluation and in follow up Very useful in lymphoma evaluation Less useful for several other malignancies Still being studied Notorious undercall of AdCysticCa Thyroid disease is very topical, and new developments are now showing greater promise False positives must always be considered

29 Fake Out: Melanoma Primary, Dental Abscess

30 Layers of Deep Cervical Fascia Defines Spaces

31 Named Spaces of Suprahyoid Neck

32 PPS: PleomorphicAdenomaPosterolateral flattening parotid

33 RPS: Anterior Displacement of PPS

34 MS: Odontogenic Lesions (Abscess)

35 PS: Mucoepidermoid Carcinoma

36 PS: Benign Lesions Warthin s Tumor

37 INFRAHYOID NECK: Major Fascial Spaces Visceral Thyroid, parathyoids, aerodigestive tract, paratracheal nodes Carotid Retropharyngeal Perivertebral Posterior cervical

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39 CT

40 CT

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42 Hyoid Bone Level

43 High Supraglottic Level

44 Mid Supraglottic Level

45 Low Supraglottic Level

46 Glottic Level

47 Subglottic Level

48 GlotticSCCa

49 TransglotticSCCa

50 CN V2 Adenoid Cystic Ca of Palate

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52 Important Imaging Points Radiology dictum is describe full extent of primary disease and evaluate scanned volume for metastasis In H&N cancer, this should include review of cervical lymph nodes Great undiagnosed condition is PNS of H&N malignancies Critical prognostic information Failure to see almost guarantees undertreatment

53 Conclusions Cross sectional imaging is best evaluated by a spatial approach Knowledge of spaces can narrow differential diagnoses CT, MR and PET CT can contribute to initial evaluation and play key roles in follow up of patients with H&N cancer