imaging of the paranasal sinuses - orl-hno.ch · nervus opticus nervus maxillaris nervus vidianus ....
TRANSCRIPT
![Page 1: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/1.jpg)
Imaging of the Paranasal Sinuses
Bettlach
24.08.2018
14. Sommerschule
Christoph Schlegel
![Page 2: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/2.jpg)
Christoph Schlegel Sommerschule 2018
Conventional Radiology
NNH-Status: okzipito-frontal: frontal sinus, anterior ethmoid
okzipito-nasal : maxillary and frontal sinus
axial: sphenoid and ethmoidal sinus
Radiation exposure:
2 mGy per exposure
(dose for cataract 2 Gy)
![Page 3: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/3.jpg)
Christoph Schlegel Sommerschule 2018
Conventional Radiology
inadequate sensivity and specifity
superseded by CT
![Page 4: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/4.jpg)
Single detector row CT
2 Zeilen 1990
4 Zeilen 2000
8 Zeilen 2002
16 Zeilen 2004
64 Zeilen 2005
2x 64 Zeilen 2006
2x 128 Zeilen 2009
Multi detector row CT
4
16
Multislice Spiral CT
![Page 5: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/5.jpg)
Christoph Schlegel Sommerschule 2018
Paranasal Sinus CT Protocol
high resolution axial scan from alveolar process to frontal sinus
collimation 0.6mm
overlapping slice reconstruction 0.6/0.4mm, mAs <200
reconstruction: axial, coronal, sagittal
iv contrast*: tumor, inflammation, vascular lesion
not required for preop assessment of anatomy
![Page 6: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/6.jpg)
Christoph Schlegel Sommerschule 2018
Review: Radiation Dose
• radiation dose paranasal sinus CT 0.5-1mGy
• conventional x-ray paranasal sinus 0.2 mGy/expos.
• average diagnostic dose /per capita CH: 1mGy, GB 0.33mGy
• transatlantic flight (round trip) 0.1mGy
• cataract of eye lens: > 2 Gy
![Page 7: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/7.jpg)
Christoph Schlegel Sommerschule 2018
• preoperative anatomy, residual mucosal disease
• pattern of bone destruction, skull base defects
• navigation- CT , CT guided biopsies
CT
MRI
• soft tissue differentiation: retention, tumor, cellularity,
vascularity
• meningeal, neural, vascular involvement
![Page 8: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/8.jpg)
Christoph Schlegel Sommerschule 2018
Complementary Role CT MR
![Page 9: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/9.jpg)
Christoph Schlegel Sommerschule 2018
Meningo-Encephalocele
![Page 10: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/10.jpg)
Christoph Schlegel Sommerschule 2018
![Page 11: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/11.jpg)
Christoph Schlegel Sommerschule 2018
Clival Chordoma
![Page 12: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/12.jpg)
Christoph Schlegel Sommerschule 2018
Angiography
diagnostic use for selected cases
superselective embolisation: intractable epistaxis; M. Osler
embolisation of tumors
![Page 13: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/13.jpg)
Christoph Schlegel Sommerschule 2018
Juvenile Nasopharyngeal Angiofibroma
![Page 14: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/14.jpg)
Christoph Schlegel Sommerschule 2018
Orbital Complication: Subperiostal Abscess
![Page 15: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/15.jpg)
Christoph Schlegel Sommerschule 2018
Endocranial Complikation: Epidural and Soft Tissue Abscess in Frontal Sinusitis
![Page 16: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/16.jpg)
Christoph Schlegel Sommerschule 2018
Chronic Rhinosinusitis (without Nasal Polyps)
N.B.: after medical treatment
![Page 17: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/17.jpg)
Christoph Schlegel Sommerschule 2018
Chronic Rhinosinusitis (with Nasal Polyps)
N.B.: after medical treatment
![Page 18: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/18.jpg)
Christoph Schlegel Sommerschule 2018
Red Flags…
Consider other diagnosis:
unilateral symptoms
bleeding, crusting
cacosmia
orbital symptoms( oedema, displaced globe, double
vision)
severe frontal headache, frontal swelling
signs of meningitis
neurological signs
urgent investigation and intervention
![Page 19: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/19.jpg)
Christoph Schlegel Sommerschule 2018
Granulomatose mit Polyangiitis (M. Wegener)
![Page 20: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/20.jpg)
Christoph Schlegel Sommerschule 2018
Aspergilloma (fungus ball)
![Page 21: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/21.jpg)
Christoph Schlegel Sommerschule 2018
Odontogenic Sinusitis
![Page 22: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/22.jpg)
Christoph Schlegel Sommerschule 2018
Inverted Papilloma
![Page 23: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/23.jpg)
Christoph Schlegel Sommerschule 2018
Inverted Papilloma
![Page 24: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/24.jpg)
Christoph Schlegel Sommerschule 2018
Mucocele of Maxillary Sinus
![Page 25: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/25.jpg)
Christoph Schlegel Sommerschule 2018
Mucocele of Sphenoid Sinus
Dehiscent Internal Carotid Artery
![Page 26: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/26.jpg)
Christoph Schlegel Sommerschule 2018
Complicated Nose Fracture
![Page 27: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/27.jpg)
Christoph Schlegel Sommerschule 2018
Zygomatic Fracture
![Page 28: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/28.jpg)
Christoph Schlegel Sommerschule 2018
CSF-Leak
High resolution CT
MRI (T2)
β2-transferrin or β-trace
In selected cases: Intrathecal fluorescein injection
![Page 29: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/29.jpg)
Christoph Schlegel Sommerschule 2018
CSF-Leak
![Page 30: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/30.jpg)
Christoph Schlegel Sommerschule 2018
Dacryo CT Scan
![Page 31: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/31.jpg)
Christoph Schlegel Sommerschule 2018
Dacryo CT Scan
![Page 32: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/32.jpg)
Christoph Schlegel Sommerschule 2018
FESS: Preoperative Evaluation (CT Checklist)
uncinate process
ethmoidal roof, skull base
ethmoidal arteries
orbit, optic nerve
internal carotid artery
anatomical variations of ethmoidal cells
![Page 33: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/33.jpg)
Christoph Schlegel Sommerschule 2018
Uncinate Process
Simmen D, Jones N: Manual of Endoscopic Sinus Surgery. Thieme 2014
A B1 B2
![Page 34: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/34.jpg)
Christoph Schlegel Sommerschule 2018
Preoperative Checklist: Uncinate Process
Typ A (~ 75%): Insertion at Lamina
papyracea
«Recessus terminalis»
Frontal sinus drainage
pathway directly in middle
meatus
![Page 35: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/35.jpg)
Christoph Schlegel Sommerschule 2018
Preoperative Checklist: Uncinate Process
Typ B1: Insertion at skull base
Frontal sinus drainage
pathway in ethmoidal
infundibulum
![Page 36: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/36.jpg)
Christoph Schlegel Sommerschule 2018
Preoperative Checklist: Uncinate Process
Typ B2: Insertion at middle turbinate
Frontal sinus drainage
pathway in ethmoidal
infundibulum
![Page 37: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/37.jpg)
Wormald PJ: The agger nasi cell: the key to understand the anatomy of the frontal recess Otolaryngol Head Neck Surg 2003; 129:497-507
Frontal Recess
![Page 38: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/38.jpg)
Anatomy of the Frontal Recess
"frontal drainage pathway"
"fronto-ethmoidal cell"
"agger nasi cell"
![Page 39: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/39.jpg)
Frontal Recess: Sagittal Reconstruction
Fronto-ethmoidal cells:
• Agger nasi cell
• K1 to K4 cells
• Suprabullar cells
• Frontal bullar cells
• Interfrontal sinus septal cell
![Page 40: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/40.jpg)
Christoph Schlegel Sommerschule 2018
![Page 41: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/41.jpg)
Christoph Schlegel Sommerschule 2018
anterior
posterior
(medial)
![Page 42: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/42.jpg)
Christoph Schlegel Sommerschule 2018
![Page 43: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/43.jpg)
Preoperative Checklist: Ethmoid Roof Cribriform Plate
![Page 44: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/44.jpg)
Preoperative Checklist: Anterior Ethmoidal Artery
![Page 45: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/45.jpg)
Preoperative Checklist: Optic nerve
![Page 46: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/46.jpg)
Preoperative Checklist: Internal Carotid Artery
![Page 47: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/47.jpg)
Concha bullosa media
![Page 48: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/48.jpg)
Haller Cell
![Page 49: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/49.jpg)
Haller Cell
![Page 50: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/50.jpg)
Onodi Cell
![Page 51: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/51.jpg)
Pneumatized Inferior Turbinate
![Page 52: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/52.jpg)
3 Nervs ???
Nervus opticus
Nervus maxillaris
Nervus vidianus
![Page 53: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/53.jpg)
Cone Beam CT (Digitale Volumentomographie)
![Page 54: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/54.jpg)
Christoph Schlegel Sommerschule 2018
Cone Beam CT
Corresponds to a C-arm with 3D images
Digital volume tomography
Cone revolves around patient for 360°
Since 2000
Office use, no need for a radiologist
![Page 55: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/55.jpg)
Christoph Schlegel Sommerschule 2018
Low dose multislice CT Cone beam CT
MSCT DVT
Acquisition time ( motion artefacts)
2 sec 20-40 sec
Radiation exposure 0.2-0.5 mSV (+ 30-40%)
0.1-0.3 mSV
Image homogenity + +
Bone window Soft tissue window
+ +
+ -
Cost - +
Image reconstruction + +
De Cock et al. A comparative study for image quality and radiation dose of a cone beam computed
tomography scanner and a multislice computed tomography scanner for paranasal sinus imaging.
Eur Radiol (2015) 25:1891–1900
Al Abduwani et al. Cone beam CT paranasal ainuses versus low dose meltidetector CT studies.
Am J Otolaryngol (2016)37:59-64
![Page 56: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/56.jpg)
Navigation: Localization Systems
Optical tracking systems Electromagnetic tracking systems
+ cordeless + free movement of surgeon
- line of sight - magnetic interference
![Page 57: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/57.jpg)
Christoph Schlegel Sommerschule 2018
Accuracy
Depends on: CT scan and its reconstruction
Registration !
Patient motion, motion of reference points !
Generally accepted range: ± 1 mm (=2 mm)
Shift in accuracy from anterior to posterior
up to 9 mm (z axis)
![Page 58: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/58.jpg)
Intraoperative Manual Registration Refinement
New feature to adjust disaccuracy i.e. in the depth
Before After
![Page 59: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/59.jpg)
Navigation starts the day before surgery by:
Analysis of the CT-scan (coronar,axial,sagittal):
where is the frontal drainage pathway?
Step by step surgical plan
![Page 60: Imaging of the Paranasal Sinuses - orl-hno.ch · Nervus opticus Nervus maxillaris Nervus vidianus . Cone Beam CT (Digitale Volumentomographie) Christoph Schlegel Sommerschule 2018](https://reader030.vdocuments.net/reader030/viewer/2022021611/5cef6d2488c99330508dc590/html5/thumbnails/60.jpg)
Christoph Schlegel Sommerschule 2018
Suggested Reading
Simmen D, Schuknecht B: Computed tomography of paranasal sinuses.
A preoperative checklist. Laryngo-Rhino-Otology 1997; 76:8-13
Simmen D, Jones N: Manual of endoscopic Sinus and Skull Base
surgery. Thieme 2014, second edition
Wormald PJ: Endoscopic Sinus Surgery: Anatomy, Three-Dimensional Reconstruction, and Surgical Technique . Thieme 2018, fourth edition