nasal cavity - ?· fovea ethmoidalis lateral lamella of cribriform plate medial lamella of...

Download Nasal Cavity - ?· Fovea ethmoidalis Lateral lamella of cribriform plate Medial lamella of cribriform…

Post on 31-Jul-2019

212 views

Category:

Documents

0 download

Embed Size (px)

TRANSCRIPT

  • The Fastest 20 Minutes in

    Sinonasal Anatomy

    Michelle A. Michel, MDProfessor of Radiology and Otolaryngology

    Medical College of Wisconsin, Milwaukee

    Sinonasal AnatomyOverview

    Nasal cavity

    Anterior skull base

    Ostiomeatal complex

    Frontal sinus & recess

    Sphenoethmoidal region

    Disclosures: None

    Illustrations Courtesy Elsevier/Amirsys, Inc.

    Sinonasal AnatomyGlobal Anatomy

    Nasal cavity centrally

    Paranasal sinuses

    surround

    Anterior cranial fossa

    above

    Oral cavity below

    Central skull base &

    nasopharynx behindwww.goeshealth.com

    www.webmd.com

    Nasal Cavity

    Boundaries

    Septum

    Turbinates & Meati

    Lamellae

    Drainage Pathways

    Variants

    Sinonasal AnatomyNasal Cavity

    Sinonasal Anatomy

    Nasal Cavity - Nasal Septum

    Bony & cartilaginous

    Ethmoid & vomer

    Septal cartilage

    Deviation (up to 80%)

    Quantify it

    At jxn of cartilage and vomer

    Associated variants of MT

    +/- Spur

    ? Contact with lateral wall

    Reporting important

    septoplasty prior to ESS

    http://goeshealth.com/wp-content/uploads/2011/12/symptoms-of-sinusitis.jpg
  • Sinonasal AnatomyNasal Cavity Turbinates & Meati

    Turbinates Inferior

    Middle

    Superior

    (Supreme)

    Meati Middle

    Frontal, anterior ethmoid, & maxillary

    Superior

    Posterior ethmoid & sphenoid via SER

    Inferior

    NLD

    Sphenopalatine foramen

    Sinonasal AnatomyNasal Cavity Middle Turbinate

    Complex morphology

    Attachments Anterior vertical

    Oriented sagittally

    Attaches to cribriform plate

    Mid lateral Oriented in an oblique then

    coronal plane

    Attaches to lamina papyracea

    Basal lamella

    Divides anterior & posterior ethmoids

    Posterior Oriented axially

    Attaches to medial max sinus wall

    Sinonasal AnatomyLamellar Anatomy

    Bony struts develop in the cartilaginous olfactory capsule

    Generally oriented in a coronal/oblique coronal plane

    Have superior attachments to CP/FE & lateral attachments to lamina papyracea Uncinate Process

    Bulla lamella

    Basal/ground lamella

    Superior turbinate

    *

    Sinonasal AnatomyNasal Cavity Drainage Pathways

    Patterns of disease

    Infundibular

    OMC

    Frontal recess

    Sphenoethmoidal

    recess

    Babbel RW, Harnsberger HR, Sonkens J, and Hunt S. 2002 AJNR 13:903-12

    Courtesy H. Ric Harnsberger

    Sinonasal AnatomyNasal Cavity Turbinate Variants

    Concha Bullosa (24-55%) CB & Pneumatized Inf Turb Paradoxical MTs (26%)

    Courtesy Mauricio Castillo, MD

    Concha Bullitis Concha Retention Cyst Osteoma in Pneumatized VL

    Anterior Skull Base

    Cribriform Plate

    Fovea Ethmoidalis

    Olfactory Recess

    Variants

  • Fovea ethmoidalis

    Lateral lamella of

    cribriform plate

    Medial lamella of

    cribriform plate

    Vertical lamella of

    middle turbinate

    Sinonasal AnatomyAnterior Skull Base

    Sinonasal AnatomyAnterior Skull Base Keros Classification

    1 - 3 mm 3 - 7 mm 7 - 16 mm

    Hoxworth JM, Glastonbury CM, Fischbein NJ, Dillon WP. Focal opacification of the olfactory recess on sinus

    CT: just an incidental finding? AJNR Am J Neuroradiol. 2008 May;29(5):895-7.

    Sinonasal AnatomyAnterior Skull Base - Olfactory Recess

    Located between septum

    and vertical lamella of MT

    ORO uncommon in the

    absence of ethmoid

    mucosal disease, prior

    ethmoidectomy or

    turbinectomy

    Consider neoplasm or

    cephalocele

    ENB

    MRI warrantedCases Courtesy Christine Glastonbury MBBS

    EsthesioneuroblastomaCephalocele

    Sinonasal AnatomyAnterior Skull Base - Variants

    Ostiomeatal Complex

    Components Uncinate Process

    Ethmoid Bulla

    Middle Turbinate

    Infundibulum

    Hiatus Semilunaris

    Middle Meatus

    Maxillary Sinus

    Variants

    Sinonasal AnatomyOstiomeatal Complex

    E

    MTU

    *

  • Sinonasal AnatomyOstiomeatal Complex Uncinate Process

    Uncinate Process

    Variable attachments

    Pneumatized (4%)

    Everted

    Can be mistaken for a

    double MT on endoscopy

    Atelectatic

    Max sinus hypoplasia &

    SSS

    Predisposes to orbital

    injury in ESS

    Adapted from Stammberger, et al. Functional Endoscopic

    Sinus Surgery, BC Decker, Philadelphia, 1991

    Sinonasal AnatomyOstiomeatal Complex Uncinate Process

    Sinonasal AnatomyOstiomeatal Complex Maxillary Sinus

    Roof = orbital floor (V1)

    Floor = alveolar process of

    maxilla

    Ostium at superior medial wall

    Drains into base of ethmoid

    infundibulum

    Reduced volume

    predisposed to orbital

    penetration in ESS

    Hypoplasia, SSS

    Hyperpneumatized dental

    roots exposed & predisposed to

    recurrent odontogenic sinusitisCourtesy Deborah Shatzkes MD

    Sinonasal AnatomyOstiomeatal Complex Ethmoid Variants

    Infraorbital ethmoid cell

    Haller cell

    Along orbital floor

    Extend lateral to the

    plane of the lamina

    papyracea

    Reported in 10-45%

    Narrow ethmoid

    infundibulum

    Frontal Sinus & Recess

    Frontal Sinus

    Frontal Beak & Ostium

    Frontal Recess

    Agger Nasi Cell

    Variants

    Sinonasal AnatomyFrontal Sinus and Frontal Recess

  • Sinonasal AnatomyFrontal Sinus and Frontal Recess - Variants

    Frontal cells

    Cells other than

    named cells

    Agger nasi

    Pneumatized CG

    Intersinus septal cell

    Within the frontal

    sinus or recess

    Anterior to FR

    Types I-IV

    Type 1 Type 2

    Type 3 Type 4

    SOE (right) & Type 3 FC (left)

    Sinonasal AnatomyFrontal Sinus and Frontal Recess - Variants

    Sphenoethmoidal Region

    Posterior Ethmoids

    Sphenoid Sinus & Ostium

    Sphenoethmoidal Recess

    Variants

    * *

    Sinonasal AnatomySphenoethmoidal Region

    *

    Sinonasal AnatomySphenoethmoidal Region

    Sinonasal AnatomySphenoethmoidal Region

    Critical anatomic relationships Optic nerve

    Internal carotid artery

    V2

    Vidian nerve

    Floor of sella

  • Sphenoid septations

    Pneumatization variants

    Anterior clinoid (6-13%)

    Opticocarotid recess

    Dorsum sella

    Lateral and pterygoid

    recesses

    Dehiscent ICA (25%) &

    optic canal (24%)

    Sphenoethmoidal cells

    Sinonasal AnatomySphenoethmoidal Region - Variants

    Sinonasal AnatomySphenoethmoidal Region - Variants

    Sphenoethmoidal cells

    Onodi

    Posterior ethmoid cell

    extending lateral to

    sphenoid sinus

    Reported in 3-14%

    In proximity to CN2 & ICA

    Horizontal septation is a

    clue on coronal imaging

    fessfreeserver.com

    Sinonasal AnatomySphenoethmoidal Region

    Sphenoethmoidal Cell

    Sinonasal AnatomySphenoethmoidal Region - Variants

    Sphenoethmoidal Cell

    Courtesy H. Ric Harnsberger MD

    Sinonasal AnatomySphenoethmoidal Region - Variants

    Early Anterior Clinoid Mucocele

    Knowledge of drainage pathways key to understanding functional anatomy and patterns of disease

    Recognize variants that may predispose to disease or risk of ESS complications

    Axial CT with coronal and sagittal reformatted images demonstrate anatomy optimally

    Sinonasal AnatomyKey Points

Recommended

View more >