Imaging for Endoscopic Sinus
           Surgery




 Dr. Prahlada N.B   M.S (PGIMER, Chandigarh)
Karnataka ENT Hospital & Research Center,
           Chitradurga, Karnataka.
Imaging v/s Endoscopy



         V/S
Surgery done without imaging
Imaging modalities
        CT Scan is choice of Imaging




Plain X-Ray        CT Scan             MRI
Patient Preparation
• Course of Antibiotics & Decongestants
• Sympathomimetic Nasal Spray 15 min before
  CT procedure
• Patient to blow the nose just before procedure
Reading CT Films
•   Coronal Images
•   Mark R/L sides properly
•   Read from Nasion to Sphenoid sinus
•   Study following in all Sections
                        - Nasal Septum
                        - Lamina Papyracea
                        - Skull Base
Normal Anatomy
Coronal Section : At Nasion
Coronal Section : At Agger Nasi
Frontal Recess




Sagittal Section    Coronal Section
Lacrimal Apparatus
Coronal Section : At OMC
Anterior Skull Base
Ethmoid Infundibulum




Axial Section     Coronal Section
Middle turbinate attachements
  I Part     II Part     III Part




Vertical    Oblique     Horizontal
Lateral Recess




Coronal Section     Sagittal Section
Coronal Section : At Post. Ethmoid
Posterior Ethmoid Cells (Onodi)




Axial Section      Coronal Section
Coronal Section : At Sphenoid
Axial Section : At Frontal
Axial Section : At Optic nerve
Axial Section : At Maxillary sinus
Anatomical Variations
Variations : Frontal Sinus




Coronal Section     Axial Section
Variations : Frontal Sinus




Coronal Section    Axial Section
Variations : Frontal Sinus




Axial Section     Coronal Section
Variations : Frontal Cells


Type I                                  Type II




Type III                                Type IV
Variations : Agger Nasi Cells
Variations : Agger Nasi Cells




Agger causing disease   Large Agger Nasi cell
Variations : Frontal Recess
Variations : Anterior Skull Base
 Type I      Type II     Type III




1 - 3 mm    4 - 7 mm     8 - 16 mm
Variations : Uncinate process




Medially bent      Pneumatized
Variations : Bulla Ethmoidalis




                    Absent Bulla
Variations : Ethmoid Sinus
Variations : Haller’s Cells
Variations : Middle turbinate




Concha    Paradoxic MT   Interlamellar
Rostrum of the Sphenoid
Sphenoid Pneumatization types
           Conchal
Sphenoid Pneumatization types
           Presellar
Sphenoid Pneumatization types
            Sellar
Variations : Sphenoid Sinus




  Extensive         Pterygoid
pneumatization    penumatization
Variations : Sphenoid Sinus




Dehiscent nerves   ACP penumatization
Variations : Sphenoid Sinus




Dehiscent Optic Nerve   Dehiscent Int. Carotid.a
Variations : Sphenoid Sinus




Absent Septa      Multiple Septae
Variations : Sphenoid Sinus




Septa ending on Optic   Septa ending on Carotid
CT in Pathology
Acute Sinusitis
• Air Fluid level
• Mucosal thickening
• Complete opacification of the sinus
Chronic Sinusitis
•   Ethmoid sinus is commonly involved
•   Mucosal thickening
•   Bone remodeling due to osteitis
•   Polyposis
Fungal Sinusitis
•   Allergic fungal sinusitis
•   Sinus mycetoma
•   Acute invasive fungal sinusitis
•   Chronic invasive fungal sinusitis
•   Chronic granulomatous fungal sinusitis
Allergic fungal sinusitis
• Complete opacification of multiple sinuses
• Sinus expansion & erosion of sinus wall
• High attenuation areas due to metals
Sinus Mycetoma
• Focal area of increased attenuation that is
  created within a deseased sinus
Acute invasive fungal sinusitis
• Aggressive bone erosion
• Extension of disease into adjacent soft
  tissues
• Intrasinus high attenuation may not be
  present
Bening polyp
• Homogenous, well circumscribed
  hypodense/isodense mass
AC Polyp
Mucocoele
• Hypodense, non-enhancing mass that fills
  and expands the sinus cavity
Mucocoele




Frontal               Sphenoid
Complications of FESS
Complication : NLD injury
Complication : ACF injury
Complication : CSF Leak
Complication :
Orbital Haemorrhage
Complication :
Medical rectus injury
Complication :
Pneumo-encephaloceole
Complication :
Optic Nerve injury
Complication : Haemorrhage
Thank you




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Imaging for Endoscopic Sinus Surgery