Computed Tomography: Areas of Surgical Importance

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Computed TomographyAreas of Surgical Importance

• Reda Kamel, M.D.
• Professor of Rhinology
• Cairo University - Egypt

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Plain Xray Computed tomography
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Computed Tomography CT

• 1-When to ask for CT?
• 2- How to order a CT?
• 3- How to prepare the patient for a CT?
• 4- Where to perform the CT?
• 5- How to study a CT?
• 6- When to ask for MRI?

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5- How to study the CT?

• A- Overall view
• general idea
• B- Detailed study meticulous study

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A- Overall view general idea

• Nasal cavity
• Nasopharynx
• Sinuses frontal, maxillary, anterior ethmoid,
  posterior ethmoid, Sphenoid
• Extra-sinonasal areas orbit, cranial cavity,
  sub-cutaneous, deep face

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Areas of Surgical Importancecoronal sections

• 1- Anterior Frontal
• 2- Superior Skull base
• 3- Lateral Orbit
• 4- Inferior Ostiomeatal complex
• 5- Posterior Posterior ethmoids
• 6- Far posterior Sphenoid sinus

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1- Anterior Frontal

• Frontal sinus
• Frontal ostium
• Frontal recess
• Agger nasi cells
• Lacrimal sac
• Nasolacrimal duct
• Notice the Defect of the lacrimal sac

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2- Superior Skull base

• Crista Galli
• Perpendicular plate of ethmoid bone
• Cribriform plate
• Middle turbinate
• Lateral lamella
• Fovea ethmoidalis
• Anterior ethmoid artery AEA
• Notice the Stepladder appearance of the skull
  base anteriorly

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Skull base anterior ethmoids AEA

• Shape
• Level
• Thickness

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3- Lateral Orbit

• Lamina papiracea
• Floor of the orbit
• Roof of the orbit
• Notice the Configuration, Integrity, Angle
  Slope of these boundaries

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3- Lateral Orbit
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4- Inferior Ostiomeatal complex

• Uncinate process
• Maxillary ostium
• Bulla ethmoidalis
• Middle turbinate
• Hiatus semilunaris inferior
• Infundibulum
• Hiatus semilunaris superior
• Lateral sinus
• Notice This is the area of the OMC and Ostia

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4- Inferior Ostiomeatal complex (cont.)
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5- Posterior Posterior ethmoids

• Posterior ethmoid
• Superior turbinate
• Roof
• Lamina papiracea
• Optic nerve
• Sphenopalatine foramen
• Notice the Change in the roof (flat) Relations
  to near by important structures

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Skull base posterior ethmoids
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6- Far posterior Sphenoid sinus

• Optic nerve
• Internal carotid artery
• Septa
• Maxillary nerve
• Vidian nerve
• Palatinovaginal canal
• Nasopharynx
• Notice the Foramina Indentations

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6- Far posterior Sphenoid sinus
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Areas of Surgical Importanceconclusions

• Coronal cuts
• 1- Anterior Frontal
• 2- Superior Skull base
• 3- Lateral Orbit
• 4- Inferior Ostiomeatal complex
• 5- Posterior Posterior ethmoids
• 6- Far posterior Sphenoid sinus

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