Sinus fungus ball is defined as noninvasive chronic fungal rhinosinusitis occurring in immunocompetent patients with regional characteristics. The clinical and imaging characteristics of paranasal sinus fungus ball were retrospectively investigated in 104 Japanese patients. All patients underwent endoscopic sinus surgery. Preoperative computed tomography (CT), magnetic resonance (MR) imaging, age, sex, chief complaint, causative fungus, and clinical outcome were analyzed. Patients were aged from 25 to 79 years (mean 58.8 years). Female predominance was noted (58.7%). Most common symptoms were nasal discharge and facial pain. CT showed high density area in 82.0% of the cases (82/100), whereas T2-weighted MR imaging showed low intensity area in 100% of the cases (32/32). Histological examination showed that most causative agents were
Fungal rhinosinusitis is encountered in about 10% of patients requiring surgery for diseases of the nose and sinuses, and fungal or mixed fungal and bacterial infections are responsible for 13.5% to 28.5% of all cases of maxillary sinusitis [
Several case series have been reported [
We retrospectively reviewed the clinical records of patients diagnosed with sinus fungus ball who underwent surgery at the Department of Otorhinolaryngology, Jikei University Hospital, Tokyo, Japan, between April 2005 and November 2010. The diagnosis was based on histological examination of the surgically removed material. Patients diagnosed with invasive fungal sinusitis or allergic fungal sinusitis (AFS) were excluded. We analyzed age, sex, chief complaint, location of the fungus ball, presence of high density area on computed tomography (CT), presence of low intensity area on T2-weighted magnetic resonance (MR) imaging, causative fungus, and surgical outcome. Good outcome is defined as opening of the operated sinus. Patients were followed up for 6 months postoperatively. The institutional review board of Jikei University School of Medicine approved the study.
One hundred four patients aged 25 to 79 years (mean 58.8 years) were diagnosed with sinus fungus ball based on the histological findings. Female dominance was seen with 61 female patients (58.7%) and 43 male patients (41.3%). Major presenting symptom was purulent nasal discharge (35.6%) and facial pain (24.0%) (Table
Chief complaint.
Symptoms |
|
(%) |
---|---|---|
Purulent nasal discharge | 37 | (35.6) |
Facial pain | 25 | (24.0) |
Post nasal drip | 14 | (13.5) |
Facial discomfort | 9 | (8.7) |
Nasal obstruction | 4 | (3.8) |
CT and MR imaging findings.
|
|
---|---|
High density area on CT | 82/100 (82%) |
Low intensity area on T2-weighted MR imaging | 32/32 (100%) |
The paranasal sinus localizations of fungus ball in the 104 patients are shown in Table
Paranasal sinus localizations.
|
(%) | |
---|---|---|
Maxillary sinus | 86 | (82.7) |
Sphenoid sinus | 11 | (10.6) |
Maxillary sinus and ethmoid sinus | 5 | (4.8) |
Maxillary sinus and sphenoid sinus | 1 | (1.0) |
Ethmoid sinus | 1 | (1.0) |
| ||
Total | 104 | (100) |
Histological examination of fungus ball.
|
(%) | |
---|---|---|
|
98 | (94.2) |
|
3 | (2.9) |
|
1 | (1.0) |
Unable to differentiate | 2 | (1.9) |
| ||
Total | 104 | (100) |
Culture study of fungus ball.
|
(%) | |
---|---|---|
|
10 | (15.2) |
|
1 | (1.5) |
Negative | 55 | (83.3) |
| ||
Total | 66 | (100) |
All cases were treated with endoscopic sinus surgery. The affected sinus was widely opened and the mass was meticulously removed. Edematous mucosa of the affected sinus was curetted leaving the basal membrane intact. The sinus was irrigated with normal saline according to the surgeon’s preference.
Patients were instructed to perform nasal lavage with normal saline two times per day. The nasal cavity was examined with a rigid endoscope and secretions and crusts were cleaned at the outpatient department. Any small pieces of fungus ball in the operated sinus were removed immediately. Recurrence with occlusion of the operated sinus occurred in 3 (3.2%) of 94 patients who visited the outpatient clinic at least once.
Sinus fungus ball is the most common form of fungal sinusitis. Fungal sinusitis is classified into two major categories, noninvasive fungal sinusitis and invasive fungal sinusitis [
Sinus fungus ball is mostly encountered in older individuals with the average age at presentation of 49 years (
Common CT findings include the following: ipsilateral involvement; bony thickening of the diseased sinus wall; and hyperdense area within the lesion (Figure
Typical neuroimaging findings of maxillary fungus ball. (a) Coronal CT scan with soft tissue density. Left maxillary sinus is completely filled with material. High density spots are seen. (b) Coronal T2-weighted MR image. Extremely low signal intensity to signal void indicates the presence of fungus ball. Peripheral high intensity area indicates edematous mucosa.
Representative case of fungus ball identifiable only on MR imaging. (a) Coronal CT scan with soft tissue density. Left maxillary sinus is filled with material. Irregular surface of the material suggests the possibility of fungus ball. High density spot is not seen. (b) Coronal T2-weighted MR image. Extremely low signal intensity to signal void indicates the presence of fungus ball.
In this study, the most common localizations were the maxillary sinus (82.7%) and the sphenoid sinus (10.6%) as in previous studies [
The causative fungus was mainly
The prognosis for sinus fungus ball is favorable. The reported recurrence rates are 0% (
In conclusion, MR imaging provides high sensitivity but poor specificity for the identification of sinus fungus ball but is valuable for the investigation of undiagnosed cases detected with paranasal CT. The prognosis for fungus ball is very good, but recurrence is possible. Wide opening of the affected sinus and complete removal of the fungus ball are essential.
There is no conflict of interests.