Address for correspondence : Chang-Hoon Kim, MD, PhD, Department of Otorhinolaryngology, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
Tel : +82-2-2228-3609, Fax : +82-2-393-0580, E-mail : ENTMAN@yuhs.ac

Introduction

Fibrous dysplasia (FD) is a rare type of fibro-osseous lesion characterized by fibroblastic proliferation and progressive substitution of the normal bone with fibrotic disorganized bony trabeculae.1) Although several etiological theories, such as neoplastic degeneration and genetic or embryologic modification, have been proposed, the exact pathogenesis of FD is still unknown.2,3) 70% of all FD cases are of the monostotic form, and only 10% of these involve the craniofacial bones. 30% of all FD cases are of the polyostotic form, and more than 50% of these involve the craniofacial bones.4,5) The polyostotic form may be associated with McCune-Albright syndrome, which is the most severe form of polyostotic FD. As FD has a tendency to affect membranous bones such as the femur or tibia, involvement of the sinonasal cavity is rare, and involvement of the inferior and/or middle turbinate bones is extremely rare. In this report, we describe a case of severe FD involving the right inferior and middle turbinates and the almost-complete obstruction of the right nasal cavity. We also review previously-reported cases of FD-induced nasal obstruction symptoms with inferior and/or middle turbinate involvement.

Case

A 42-year-old woman presented with nasal obstruction that had persisted for at least five years. The patient had no additional complaints of nasal symptoms, including rhinorrhea, sneezing, itching, or hyposmia. She reported no history of concurrent medical disease, except for fibroadenoma of the right breast. Endoscopic examination revealed hypertrophy of the inferior and middle turbinates of the right nasal cavity; severe septal deviation to the left nasal cavity was also noted. A computed tomography (CT) scan showed that fibrous dysplasia, involving the right frontal bone, sphenoid bone, and nasal cavity structures, had obstructed nearly the entire right nasal cavity (Fig. 1A and B). Laboratory test results, including serum calcium and alkaline phosphatase levels, were normal. As the right side, nasal cavity was nearly obstructed and the patient's symptoms were very severe; we partially removed the right inferior middle turbinate bone using a drill and bone rongeur via a navigation-assisted endoscopic approach. Conservative septoplasty to correct the lower septal area was also performed. The overlying mucosa was saved. Post-operative CT and endoscopic imaging showed a widened right nasal cavity (Fig. 1C and D). The patient's subjective symptoms were also improved, and remnant mucosa was well preserved. There were no additional complications or deterioration of symptoms over a one-year follow-up period.

Discussion

Involvement of the craniofacial and paranasal sinuses in FD is rare,6,7) and is associated with symptoms atypical for FD, including headache, epistaxis, nasal obstruction, and sinus obstructions leading to recurrent infectious conditions. We investigated all FD cases reported to involve the inferior or middle turbinate bones, and found a total of five FD cases involving the middle turbinate in addition to four cases of FD involving the inferior turbinate. Among the five cases of FD involving the middle turbinate, we could access the full English text of four reports.3,8,9,10) Based on a review of those cases, FD involving the middle turbinate was predominantly observed in female patients, whose ages ranged from 14 to 64 years. Although it has been reported that FD usually presents in the first two decades,11) our case and the review of other case reports suggest that age is not a reliable factor for the diagnosis of FD. One male patient presented with bronchial asthma, aspirin intolerance, and allergy to grass pollen, a Widal syndrome. Another patient showed a septal deviation to the contralateral side, similarly to our case. Three patients underwent resection of the middle turbinate via an endoscopic approach to reduce their nasal symptoms. A patient with McCune-Albright syndrome in the form of a unique polyostotic type of FD involving the middle turbinate was conservatively managed without surgery. In all cases, there was no reported aggravation of the disease throughout the duration of the follow-up period (Table 1). Although we did not include it in Table 1, we found an interesting case report of a patient who was diagnosed with FD of the middle turbinate pre-operatively, with the diagnosis changed to ossifying fibroma after pathologic review. This suggests that the accurate diagnosis of fibro-osseous lesions is complicated in some cases, and that radiologic, pathologic, and endocrinological evaluations should be considered.
Among the four cases of FD involving the inferior turbinate, we could access the full English text of three reports.1,12,13) Only one patient was male, and was under treatment for hematologic malignancies. This patient also suffered from pansinusitis, as revealed by CT examination. The management of sinusitis or FD was not clearly described for this case. The other two patients were females aged 29 and 68 years. Two female patients were surgically managed via endoscopic resection of the inferior turbinate. Septoplasty was performed in one patient. In all cases, there was no reported aggravation of the disease throughout the duration of the follow-up period (Table 2).
Based on our case and review of the literature, we suggest that patients whose symptoms were not specific, and maintained normal nasal mucosa should be suspected for underlying diseases such as FD. And conservative surgical management should be considered, because it was very effective for the improvement of subjective symptoms. We found that in patients with suspected FD, imaging studies should be performed to rule out the possibility of polyostotic FD. Endocrinological studies should be performed to rule out concurrent medical conditions, and physical examinations for diagnostic indicators such as café au lait spots should not be ignored. Furthermore, pathologic findings should be carefully reviewed, because different types of fibro-osseous lesions may share clinical and radiologic features.14) In all cases, the nasal mucosa overlying FD-affected tissue were in normal condition, and the initial clinical impression was of inferior or middle turbinate hypertrophy. Therefore, in the case of severe asymmetric turbinate hypertrophy, CT scans should be performed to rule out the possibility of monostotic FD affecting the nasal cavity. In all patients, endoscopic surgical removal of affected turbinate bones relieved patient symptoms and did not induce any complications. Interestingly, one study reported a case of FD of the middle turbinate causing periorbital abscesses that obstructed the middle meatus. Therefore, when a patient with FD experiences nasal symptoms, it is appropriate and effective to surgically resect the affected turbinate bone. Surgical access is via an endoscopic approach, and saving the overlying mucosa above the affected bone is important for minimization of post-operative nasal symptoms.

1. Park HJ, Cho MS, Lee SS. Fibrous dysplasia of the inferior turbinate. Int J Clin Exp Pathol 2013;6(3):531-5.

2. Alba García JR, Armengot Carceller M, Pérez Fernández CA, Díaz Fernández A, Taleb C, Campos Catalá A, et al. [An exceptional form of cranio-facial fibrous dysplasia: fibrous dysplasia of middle turbinate]. Acta Otorrinolaringol Esp 2002;53(4):291-4.

3. Saetti R, Silvestrini M, Marino F, Narne S. Fibrous dysplasia of middle turbinate associated with Widal syndrome: endoscopic treatment of a rare case. Acta Otorhinolaryngol Ital 2004;24(5):288-91.

4. Camilleri AE. Craniofacial fibrous dysplasia. J Laryngol Otol 1991;105(8):662-6.

5. Ferguson BJ. Fibrous dysplasia of the paranasal sinuses. Am J Otolaryngol 1994;15(3):227-30.

6. Hong SL, Kim SW, Won TB, Shim WS, Kim YM, Kim JW, et al. Fibrous dysplasia involving paranasal sinuses. Korean J Otolaryngol-Head Neck Surg 2007;50(4):300-4.

7. Lee KH, Cho JS, Lee IY, Kim H. A case of fibrous dysplasia limited within the maxillary sinus. Korean J Otolaryngol-Head Neck Surg 2002;45(1):86-8.

8. LaBagnara J Jr, Yuppa F, Klein MH. Fibrous dysplasia of the middle turbinate with primary hyperparathyroidism. Ear Nose Throat J 1998;77(7):552-3.

9. Stoeckli SJ, Moe KS, Kaufmann T, Bruder E. Fibrous dysplasia as a cause of periorbital abscess. Otolaryngol Head Neck Surg 1999;120(2):283-5.

10. Uzun C, Adali MK, Koten M, Karasalihoglu AR. McCune-Albright syndrome with fibrous dysplasia of the paranasal sinuses. Rhinology 1999;37(3):122-4.

11. Galvan O, Gassner EM, Neher A, Gunkel AR. Fibro-osseous lesion of the middle turbinate: ossifying fibroma or fibrous dysplasia? J Laryngol Otol 2007;121(12):1201-3.

12. Alvarez Vázquez A, Anes González G, Fernández García N. Isolated fibrous dysplasia of the inferior turbinate. Acta Otorrinolaringol Esp 2013;64(4):312-3.

13. Karligkiotis A, Terranova P, Dallan I, Castelnuovo P. Monostotic fibrous dysplasia of the inferior turbinate. Otolaryngol Head Neck Surg 2012;146(6):1035-6.

14. MacDonald-Jankowski DS. Fibro-osseous lesions of the face and jaws. Clin Radiol 2004;59(1):11-25.