**7. Fungal sinusitis**

Fungal sinusitis can be noninvasive, which includes fungus ball (mycetoma) (**Figure 11a**–**c**) and allergic fungal sinusitis (**Figure 12a**–**d**), or invasive with an acute, chronic, or granulomatous course [16].

Invasive fungal sinusitis is revealed by fungal deposits outside the sinus walls that obliterate the fat plane. The sinus wall usually is sclerotic and intact, and the spread of fungus is by the vessels through the bone (**Figure 13a**–**d**). Demineralization and erosion of the lateral nasal wall is usually seen when the maxillary sinus is involved. Invasive fungal sinusitis is most common in immunocompromised patients.

#### **Figure 11.**

*(a) Sagittal CT shows scattered calcifications in the frontal sinus opacification consistent with a fungus ball (mycetoma). (b) Coronal MRI T1 shows the central fungus ball as high signal surrounded by low signal from edematous thickened mucosal lining, while (c) coronal MRI T2 shows fungus ball with low signal, surrounded by high signal mucosal lining. The low signal is explained by the by the iron and manganese contents in the fungi.*

#### **Figure 12.**

*Axial CT at the level of the (a) maxillary and (b) ethmoid sinuses shows panopacification. Reconstruction, with soft tissue algorithm (c) and (d), shows high attenuation in all sinuses, which is typical for allergic fungal sinusitis. Slightly thickened, sclerotic sinus walls indicate a long-standing condition.*

**19**

**Figure 14.**

*Imaging in Sinonasal Disorders*

**8. Systemic diseases**

**Figure 13.**

sinonasal manifestations are seen in 85%.

Several systemic diseases have sinonasal manifestations [18]. One of these is granulomatosis with polyangiitis (GPA) (formerly Wegener's granulomatosis), with a prevalence of 10–25/100,000. Age group mostly affected is 50–70 years. Oral and

*A 53-year-old man, who presented with diplopia. (a) Axial CT with bone algorithm was reported as chronic sphenoid sinusitis. The patient did not improve on antibiotic treatment. (b) A new examination with cerebral CT and reconstruction with soft tissue algorithm revealed scattered calcifications in the opacification and (c) erosion of the thickened, sclerotic bone, consistent with invasive fungal infection to the cavernous sinus and hence possible affection of the cranial nerves 3, 4, 5, and 6 that pass through the cavernous sinus. (d) Axial MRI with T2 sequence shows fungi with low signal surrounded by mucosal lining with high signal.*

Both extensive bone osteoneogenesis (osteitis) and destructions seen in GPA imaging are used to assess disease activity even though little is known about CT or

*(a) Coronal CT and (b) axial CT in granulomatosis with polyangiitis show status after bilateral endoscopic sinus surgery (media-antrostomy). The bone is thickened due to chronic osteitis. Notice small peripheral rim of osteoneogenesis along the lining of the left maxillary sinus. (c) Coronal CT and (d) axial CT, follow-up CT 5 years later, demonstrate extensive bilateral osteitis of the maxillary and sphenoid sinuses. Notice also the small periapical lucencies around the roots of the right upper molar, often seen in patients with granulomatosis with polyangiitis.*

*DOI: http://dx.doi.org/10.5772/intechopen.90773*

#### **Figure 13.**

*Sino-Nasal and Olfactory System Disorders*

**18**

**Figure 12.**

**Figure 11.**

*contents in the fungi.*

*(a) Sagittal CT shows scattered calcifications in the frontal sinus opacification consistent with a fungus ball (mycetoma). (b) Coronal MRI T1 shows the central fungus ball as high signal surrounded by low signal from edematous thickened mucosal lining, while (c) coronal MRI T2 shows fungus ball with low signal, surrounded by high signal mucosal lining. The low signal is explained by the by the iron and manganese* 

*Axial CT at the level of the (a) maxillary and (b) ethmoid sinuses shows panopacification. Reconstruction, with soft tissue algorithm (c) and (d), shows high attenuation in all sinuses, which is typical for allergic fungal* 

*sinusitis. Slightly thickened, sclerotic sinus walls indicate a long-standing condition.*

*A 53-year-old man, who presented with diplopia. (a) Axial CT with bone algorithm was reported as chronic sphenoid sinusitis. The patient did not improve on antibiotic treatment. (b) A new examination with cerebral CT and reconstruction with soft tissue algorithm revealed scattered calcifications in the opacification and (c) erosion of the thickened, sclerotic bone, consistent with invasive fungal infection to the cavernous sinus and hence possible affection of the cranial nerves 3, 4, 5, and 6 that pass through the cavernous sinus. (d) Axial MRI with T2 sequence shows fungi with low signal surrounded by mucosal lining with high signal.*

## **8. Systemic diseases**

Several systemic diseases have sinonasal manifestations [18]. One of these is granulomatosis with polyangiitis (GPA) (formerly Wegener's granulomatosis), with a prevalence of 10–25/100,000. Age group mostly affected is 50–70 years. Oral and sinonasal manifestations are seen in 85%.

Both extensive bone osteoneogenesis (osteitis) and destructions seen in GPA imaging are used to assess disease activity even though little is known about CT or

#### **Figure 14.**

*(a) Coronal CT and (b) axial CT in granulomatosis with polyangiitis show status after bilateral endoscopic sinus surgery (media-antrostomy). The bone is thickened due to chronic osteitis. Notice small peripheral rim of osteoneogenesis along the lining of the left maxillary sinus. (c) Coronal CT and (d) axial CT, follow-up CT 5 years later, demonstrate extensive bilateral osteitis of the maxillary and sphenoid sinuses. Notice also the small periapical lucencies around the roots of the right upper molar, often seen in patients with granulomatosis with polyangiitis.*

MRI findings that may indicate poor prognosis [19]. Sinonasal surgery in GPA is debated [20] and may cause increased osteoneogenesis (**Figure 14a**–**c**).
