- Email: [email protected]
Maxillofacial Fibrous Dysplasia in Iran: a Case Series
Asian J Oral Maxillofac Surg. 2007;19:101-4.
Sazgar, Hassanabadi, Radji, et al
CLINICAL OBSERVATIONS
Maxillofacial Fibrous Dysplasia in Iran: a Case Series Amir Arvin Sazgar, Mohammad Sadeghi Hassanabadi, Babak Radji, Abbas Nadimi Tehrani Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
Abstract Objective: To assess the prevalence of maxillofacial fibrous dysplasia in Iran, and to determine the relative involvement of the various head and neck bones, and symptoms and pattern of treatment. Patients and Methods: A retrospective study was conducted of the patients diagnosed and treated for maxillofacial fibrous dysplasia at the Imam Khomeini Complex Hospital and Amir Alam Hospital in Iran from 1999 to 2005. Results: Nineteen patients (14 men and 5 women) with a clinical diagnosis of fibrous dysplasia of the head and neck bones were enrolled. Patients had a mean age ± standard deviation of 18.3 ± 2.3 years. The most common site was the maxilla and the most common presentation was facial deformity. The incidence of the monostotic and polyostotic forms of fibrous dysplasia was the same. Surgery was done for all patients and 10 patients required more than 1 operation. Conclusion: Maxillofacial fibrous dysplasia in Iran shows a male preponderance. The maxilla is the most common site of lesion and facial deformity the most common presentation. Monostotic and polyostotic forms of fibrous dysplasia are equally prevalent. Surgery is the most frequent treatment. Key words: Fibrous dysplasia of bone, Fibrous dysplasia, monostotic, Fibrous dysplasia, polyostotic, Maxilla
Introduction Fibrous dysplasia is a benign tumour-like, slow-growing lesion that leads to distortion, expansion, and weakening of the bone. Fibrous dysplasia is postulated to occur as a result of a developmental failure in the remodelling of primitive bone to mature lamellar bone and a failure of the bone to realign in response to mechanical stress. Failure of maturation leaves a mass of immature isolated trabeculae enmeshed in dysplastic fibrous tissue that is turning over constantly but never completes the remodelling process. In addition, the immature matrix does not mineralise normally.1,2 The precise aetiology of fibrous dysplasia is currently unknown. More recent attempts to define the disorder have focused on its underlying genetics and molecular biology.3 It is now recognised that fibrous dysplasia results from a postzygotic mutation in the guanine nucleotide-binding protein, alphastimulating activity polypeptide 1 gene. The clinical severity of the dysplasia and number of bones involved depends on the time of mutation. Clinical presentation may occur at any age, with the majority of lesions being detected by the age of 30 years. The Correspondence: Amir Arvin Sazgar, MD, Tehran University of Medical Sciences and Health Services, Faculty of Medicine, Imam Khomeini Medical Center, Dr. Gharib Ave, Keshavarz Bld., Tehran, Iran. Tel: (98 21) 6693 2288; Fax: (98 21) 6643 4020; E-mail: [email protected] © Asian 2007J Asian Oral Maxillofac Association Surg. of Oral Vol and 19, No Maxillofacial 2, 2007 Surgeons.
disease has no gender predilection. Common sites of skeletal involvement are long bones, ribs, craniofacial bones, and the pelvis. Fibrous dysplasia represents 2.5% of all bone tumours and 7.5% of all benign bone tumours. These tumours usually arise during early childhood or adolescence and tend to stabilise after puberty. Recurrence during adulthood has been noted in approximately 37% of cases.4,5 Three general subtypes of fibrous dysplasia are recognised — monostotic, polyostotic, and McCune Albright syndrome. Fibrous dysplasia can present in either a single bone (monostotic) or multiple bones (polyostotic) and be associated with other conditions.3 The monostotic form is the mildest and most common form (70% of all cases), involving the ribs and craniofacial bones. These lesions often remain asymptomatic. The polyostotic form (30% of all cases) typically occurs in childhood and affected patients tend to have more severe skeletal and craniofacial involvement. McCune Albright syndrome (3% of all cases) is more commonly found in females with short stature due to premature closure of the epiphyses, and is associated with endocrine abnormalities and pigmented cutaneous lesions with polyostotic fibrous dysplasia. 6 Mazabraud disease is a polyostotic form with soft tissue masses.6 The common clinical presentations of fibrous dysplasia are incidental findings (common in monostotic dysplasia), bone pain, deformity, and pathologic fracture. According to some studies, frontal headache is the most common 101
Maxillofacial Fibrous Dysplasia in Iran
complaint, followed by drainage and nasal obstruction associated with secondary sinusitis in fibrous dysplasia of the paranasal sinuses.7 Localised pain may be the presenting symptom in patients with fatigue fractures in high-stress areas. The degree of deformity depends on the extent and site of lesion, age of patient, and disease subtype.2 The radiographic features of fibrous dysplasia vary widely.8 Normal bone is replaced by tissue that is more radiolucent, with a greyish “ground glass” pattern that is similar in density to cancellous bone but is homogenous, with no visible trabecular pattern. The lesion characteristically is bound by a distinct rim or shell of reactive bone that is defined more sharply on its inner border than its outer border, where it may fade gradually into the normal cancellous bone.2 At initial presentation, radionuclide bone scintigraphy is useful in revealing the extent of the disease.9 Computed tomography scanning is the best technique for demonstrating the radiographic characteristics of fibrous dysplasia. Magnetic resonance imaging is a sensitive means of establishing the lesion’s shape and content and the size of the affected region. It provides complementary information when carried out in conjunction with computed tomography scanning.2 Malignant transformation of fibrous dysplasia occurs rather infrequently, with the reported prevalence ranging from 0.4 to 4.0%10-12; biopsy is not indicated when radiographic findings are characteristic of fibrous dysplasia. Although non-surgical and medical treatments, such as calcium and biphosphonate agents, exist for fibrous dysplasia, surgical procedures are often required for correction of deformities, prevention of pathologic fractures, and/or eradication of symptomatic lesions.
Patients and Methods In this retrospective study, the records of patients histologically diagnosed with fibrous dysplasia of the craniofacial bones between 1999 and 2005 at the Imam Khomeini Complex Hospital and Amir Alam Hospital in Iran were collated. Data collected included information on the involved head and neck bones (based on radiological and intraoperative findings), symptoms and signs (e.g, facial deformity, proptosis, headache, vertigo, and cranial nerve [CN] involvement), duration of symptoms from onset to Table 1. Age distribution of patients. Age (years)
No. of cases (n = 19)
0-5 6-10 11-15 16-20 21-25 26-30 31-35
0 1 7 4 5 0 2
102
diagnosis, nature of treatment, interval between surgeries if more than 1 operation was required, and associated complications. Data were evaluated using the Statistical Package for the Social Sciences (SPSS) for Windows (Version 10; SPSS, Chicago, IL, USA) software. The study was approved by the ethics committee of Tehran University of Medical Sciences.
Results The complete records of 19 patients diagnosed with fibrous dysplasia were found. Patients had a mean age ± standard deviation of 18.3 ± 2.3 years (range, 6 to 35 years). There was a male preponderance (73.6%; n = 14) in the study group, with only 5 female patients (26.5%). All patients were less than 35 years of age (Table 1). The sites of involvement were evaluated based on radiological and operative histories (Table 2 and Table 3). Fibrous dysplasia was monostotic in 9 patients and polyostotic in 10. Multiple craniofacial bone involvement alone was seen in 6 patients with polyostotic dysplasia. Apart from the head and neck bones, femur and humerus were the only other bones found involved in the lesions. Femoral involvement alone was noted in 2 patients, and humeral and femoral involvement were seen in 2 others with polyostotic fibrous dysplasia. Fibrous dysplasia of the frontal sinus and zygoma was seen in 1 patient (Table 3). The most common presentation of fibrous dysplasia was facial deformity (100%; n = 19). Other presentations included CN involvement (15.7%; n = 3), proptosis (10.5%; n = 2), headache (5.2%; n = 1), and vertigo (5.2%; n = 1). CN involvement presented as anosmia (CN I), facial hypoesthesia (CN V), and sensorineural hearing loss (CN VIII). The Table 2. Bone involvement pattern in patients with monostotic fibrous dysplasia. Bones
No. of cases (n = 9)
Frontal Ethmoid Maxilla Zygoma Mandible Temporal Nasal
1 0 1 2 2 2 1
Table 3. Bone involvement pattern in patients with polyostotic fibrous dysplasia. Bones
No. of cases (n = 10)
Frontal and zygoma Frontal and ethmoid Maxilla and nasal Temporal and zygoma Maxilla and mandible and femur Maxilla and femur and humerus Temporal and femur and humerus Maxilla and femur
1 2 2 1 1 1 1 1
Asian J Oral Maxillofac Surg. Vol 19, No 2, 2007
Sazgar, Hassanabadi, Radji, et al
Table 4. Time interval between 2 surgeries among patients needing more than 1 operation. Time between 2 surgeries (years)
No. of cases (n = 10)
1 2 3
5 2 3
incidence of monostotic and polyostotic forms was the same and none of the patients had McCune Albright syndrome. The average time between onset of symptoms and disease diagnosis was 20 months in patients with polyostotic dysplasia and 15 months in those with monostotic dysplasia, with no normal distribution in the 2 groups. Nine patients required 1 surgical operation (monostotic dysplasia, n = 6; polyostotic dysplasia, n = 3); 2 patients with polyostotic dysplasia had frontal and ethmoidal involvement, while the other had maxillary and lateral nasal involvement. Ten cases needed 2 surgical procedures (monostotic dysplasia, n = 3; polyostotic dysplasia, n = 7); 4 patients with polyostotic dysplasia had femoral and humeral involvement besides facial bone lesions (Table 4). Surgical operations were either remodelling procedures (n = 14) or total and partial resections (n = 5). A 15-year-old boy with polyostotic dysplasia (maxillary, mandibular, and femoral involvement) developed surgical complications, such as wound infection and osteomyelitis that underwent resection of the infectious area.
Discussion Fibrous dysplasia is a benign, intramedullary, fibro-osseous lesion that most probably has a genetic origin in which normal bone is replaced with fibrotic tissue and disorganised bone trabeculae. Although the disease has shown no gender predilection in some studies, there was a male preponderance in this study (male-to-female ratio, 3:1); the male-to-female ratio was 2:1 in another study.3 We propose that craniofacial involvement may be more frequent in males;2 however, this variant result could be due to the small sample size of the present study. Clinical presentation may occur at any age, with the majority of lesions being detected by 30 years of age.2 The mean age of presentation was 18.3 years, with most patients falling in the 11-15 years age group. Onset is typically in adolescence or late childhood, although more severe forms can arise in infancy.3 The results of this study approximated the findings of other research groups. The most common site of lesion was the maxillary bone, followed by the frontal, zygoma, and temporal bones. In contrast, Van Tilburg et al13 analysed skull lesions and noted that frontal bone involvement was the most common, followed by the sphenoid, ethmoid, parietal, temporal, and occipital bones. Another study also found the ethmoid to be Asian J Oral Maxillofac Surg. Vol 19, No 2, 2007
the most commonly involved bone, followed by the sphenoid, frontal, maxilla, temporal, parietal, and occipital bones.3 The most common symptoms were facial deformity, CN involvement, proptosis, headache, and vertigo. According to another study, atypical facial pain and headache were the most common presenting features, followed by symptoms suggestive of sinusitis.3 Studies of a different group showed that patients presented more often with headache and facial asymmetry due to the enlargement of facial bones.14 Painless proptosis is not uncommon. Visual dysfunction and optic atrophy can also occur in lesions involving the sphenoid wing that encroach upon the optic canal. The most common form of maxillofacial fibrous dysplasia observed in the present study was monostotic;2,15 however, another study has reported that while craniofacial bone involvement was typically seen in approximately 10% of cases with monostotic dysplasia and 50% of cases with polyostotic form, craniofacial involvement could occur in 100% of patients with severe polyostotic dysplasia.3 The incidence of monostotic and polyostotic forms was approximately the same. In conclusion, maxillofacial fibrous dysplasia in Iran shows a male preponderance. Monostotic and polyostotic forms of the disease are almost equally prevalent. Onset is typically seen in adolescence or late childhood. The maxilla is the most common site of lesion and facial deformity is the most common presentation. Surgery is the most common treatment.
References 1.
Adada B, Al-Mefty O. Fibrous dysplasia of the clivus. Neurosurgery. 2003;52:318-22.
2.
DiCaprio MR, Enneking WF. Fibrous dysplasia. Pathophysiology,
3.
Lustig LR, Holliday MJ, McCarthy EF, Nager GT. Fibrous dysplasia
evaluation, and treatment. J Bone Joint Surg Am. 2005;87:1848-64. involving the skull base and temporal bone. Arch Otolaryngol Head Neck Surg. 2001;127:1239-47. 4.
Jan M, Dweik A, Destrieux C, Djebbari Y. Fronto-orbital sphenoidal fibrous dysplasia. Neurosurgery. 1994;34:544-7.
5.
Som PM, Brandwein M, Curtin HD, editors. Head and neck imaging.
6.
Nager GT, Holliday MJ. Fibrous dysplasia of the temporal bone: update
St Louis, MO: Mosby; 2003. with case reports. Ann Otol Rhinol Laryngol. 1984;93:630-3. 7.
Brodish BN, Morgan CE, Sillers MJ. Endoscopic resection of fibroosseous lesions of the paranasal sinuses. Am J Rhinol. 1999;13:111-6.
8.
Fitzpatrick KA, Taljanovic MS, Speer DP, Graham AR, Jacobson JA, Barnes GR, et al. Imaging findings of fibrous dysplasia with histopathologic and intraoperative correlation. AJR Am J Roentgenol. 2004;182:1389-98.
9.
Zhibin Y, Quanyong L, Libo C, Jun Z, Hankui L, Jifang Z, et al. The role of radionuclide bone scintigraphy in fibrous dysplasia of bone. Clin Nucl Med. 2004;29:177-80.
10. Harris WH, Dudley HR Jr, Barry RJ. The natural history of fibrous
103
Maxillofacial Fibrous Dysplasia in Iran
dysplasia. An orthopaedic, pathological, and roentgenographic study. J Bone Joint Surg Am. 1962;44:207-33. 11. Ruggieri P, Sim FH, Bond JR, Unni KK. Malignancies in fibrous dysplasia. Cancer. 1994;73:1411-24. 12. Yabut SM Jr, Kenan S, Sissons HA, Lewis MM. Malignant transformation of fibrous dysplasia. A case report and review of the literature. Clin Orthop Relat Res. 1988;228:281-9. 13. Van Tilburg W. Fibrous dysplasia. In: Vinken PJ, Bruyn GW, editors.
104
Handbook of clinical neurology. Vol 14. Amsterdam: North Holland Publishing Co.; 1972. 14. Mahapatra AK, Gupta PK, Ravi RR. Craniofacial surgery and optic canal decompression in adult fibrous dysplasia. Neurol India. 2003;51:123-4. 15. Morrissey DD, Talbot JM, Schleuning AJ 2nd. Fibrous dysplasia of the temporal bone: reversal of sensorineural hearing loss after decompression of the internal auditory canal. Laryngoscope. 1997;107:1336-40.
Asian J Oral Maxillofac Surg. Vol 19, No 2, 2007
Sazgar, Hassanabadi, Radji, et al
CLINICAL OBSERVATIONS
Maxillofacial Fibrous Dysplasia in Iran: a Case Series Amir Arvin Sazgar, Mohammad Sadeghi Hassanabadi, Babak Radji, Abbas Nadimi Tehrani Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
Abstract Objective: To assess the prevalence of maxillofacial fibrous dysplasia in Iran, and to determine the relative involvement of the various head and neck bones, and symptoms and pattern of treatment. Patients and Methods: A retrospective study was conducted of the patients diagnosed and treated for maxillofacial fibrous dysplasia at the Imam Khomeini Complex Hospital and Amir Alam Hospital in Iran from 1999 to 2005. Results: Nineteen patients (14 men and 5 women) with a clinical diagnosis of fibrous dysplasia of the head and neck bones were enrolled. Patients had a mean age ± standard deviation of 18.3 ± 2.3 years. The most common site was the maxilla and the most common presentation was facial deformity. The incidence of the monostotic and polyostotic forms of fibrous dysplasia was the same. Surgery was done for all patients and 10 patients required more than 1 operation. Conclusion: Maxillofacial fibrous dysplasia in Iran shows a male preponderance. The maxilla is the most common site of lesion and facial deformity the most common presentation. Monostotic and polyostotic forms of fibrous dysplasia are equally prevalent. Surgery is the most frequent treatment. Key words: Fibrous dysplasia of bone, Fibrous dysplasia, monostotic, Fibrous dysplasia, polyostotic, Maxilla
Introduction Fibrous dysplasia is a benign tumour-like, slow-growing lesion that leads to distortion, expansion, and weakening of the bone. Fibrous dysplasia is postulated to occur as a result of a developmental failure in the remodelling of primitive bone to mature lamellar bone and a failure of the bone to realign in response to mechanical stress. Failure of maturation leaves a mass of immature isolated trabeculae enmeshed in dysplastic fibrous tissue that is turning over constantly but never completes the remodelling process. In addition, the immature matrix does not mineralise normally.1,2 The precise aetiology of fibrous dysplasia is currently unknown. More recent attempts to define the disorder have focused on its underlying genetics and molecular biology.3 It is now recognised that fibrous dysplasia results from a postzygotic mutation in the guanine nucleotide-binding protein, alphastimulating activity polypeptide 1 gene. The clinical severity of the dysplasia and number of bones involved depends on the time of mutation. Clinical presentation may occur at any age, with the majority of lesions being detected by the age of 30 years. The Correspondence: Amir Arvin Sazgar, MD, Tehran University of Medical Sciences and Health Services, Faculty of Medicine, Imam Khomeini Medical Center, Dr. Gharib Ave, Keshavarz Bld., Tehran, Iran. Tel: (98 21) 6693 2288; Fax: (98 21) 6643 4020; E-mail: [email protected] © Asian 2007J Asian Oral Maxillofac Association Surg. of Oral Vol and 19, No Maxillofacial 2, 2007 Surgeons.
disease has no gender predilection. Common sites of skeletal involvement are long bones, ribs, craniofacial bones, and the pelvis. Fibrous dysplasia represents 2.5% of all bone tumours and 7.5% of all benign bone tumours. These tumours usually arise during early childhood or adolescence and tend to stabilise after puberty. Recurrence during adulthood has been noted in approximately 37% of cases.4,5 Three general subtypes of fibrous dysplasia are recognised — monostotic, polyostotic, and McCune Albright syndrome. Fibrous dysplasia can present in either a single bone (monostotic) or multiple bones (polyostotic) and be associated with other conditions.3 The monostotic form is the mildest and most common form (70% of all cases), involving the ribs and craniofacial bones. These lesions often remain asymptomatic. The polyostotic form (30% of all cases) typically occurs in childhood and affected patients tend to have more severe skeletal and craniofacial involvement. McCune Albright syndrome (3% of all cases) is more commonly found in females with short stature due to premature closure of the epiphyses, and is associated with endocrine abnormalities and pigmented cutaneous lesions with polyostotic fibrous dysplasia. 6 Mazabraud disease is a polyostotic form with soft tissue masses.6 The common clinical presentations of fibrous dysplasia are incidental findings (common in monostotic dysplasia), bone pain, deformity, and pathologic fracture. According to some studies, frontal headache is the most common 101
Maxillofacial Fibrous Dysplasia in Iran
complaint, followed by drainage and nasal obstruction associated with secondary sinusitis in fibrous dysplasia of the paranasal sinuses.7 Localised pain may be the presenting symptom in patients with fatigue fractures in high-stress areas. The degree of deformity depends on the extent and site of lesion, age of patient, and disease subtype.2 The radiographic features of fibrous dysplasia vary widely.8 Normal bone is replaced by tissue that is more radiolucent, with a greyish “ground glass” pattern that is similar in density to cancellous bone but is homogenous, with no visible trabecular pattern. The lesion characteristically is bound by a distinct rim or shell of reactive bone that is defined more sharply on its inner border than its outer border, where it may fade gradually into the normal cancellous bone.2 At initial presentation, radionuclide bone scintigraphy is useful in revealing the extent of the disease.9 Computed tomography scanning is the best technique for demonstrating the radiographic characteristics of fibrous dysplasia. Magnetic resonance imaging is a sensitive means of establishing the lesion’s shape and content and the size of the affected region. It provides complementary information when carried out in conjunction with computed tomography scanning.2 Malignant transformation of fibrous dysplasia occurs rather infrequently, with the reported prevalence ranging from 0.4 to 4.0%10-12; biopsy is not indicated when radiographic findings are characteristic of fibrous dysplasia. Although non-surgical and medical treatments, such as calcium and biphosphonate agents, exist for fibrous dysplasia, surgical procedures are often required for correction of deformities, prevention of pathologic fractures, and/or eradication of symptomatic lesions.
Patients and Methods In this retrospective study, the records of patients histologically diagnosed with fibrous dysplasia of the craniofacial bones between 1999 and 2005 at the Imam Khomeini Complex Hospital and Amir Alam Hospital in Iran were collated. Data collected included information on the involved head and neck bones (based on radiological and intraoperative findings), symptoms and signs (e.g, facial deformity, proptosis, headache, vertigo, and cranial nerve [CN] involvement), duration of symptoms from onset to Table 1. Age distribution of patients. Age (years)
No. of cases (n = 19)
0-5 6-10 11-15 16-20 21-25 26-30 31-35
0 1 7 4 5 0 2
102
diagnosis, nature of treatment, interval between surgeries if more than 1 operation was required, and associated complications. Data were evaluated using the Statistical Package for the Social Sciences (SPSS) for Windows (Version 10; SPSS, Chicago, IL, USA) software. The study was approved by the ethics committee of Tehran University of Medical Sciences.
Results The complete records of 19 patients diagnosed with fibrous dysplasia were found. Patients had a mean age ± standard deviation of 18.3 ± 2.3 years (range, 6 to 35 years). There was a male preponderance (73.6%; n = 14) in the study group, with only 5 female patients (26.5%). All patients were less than 35 years of age (Table 1). The sites of involvement were evaluated based on radiological and operative histories (Table 2 and Table 3). Fibrous dysplasia was monostotic in 9 patients and polyostotic in 10. Multiple craniofacial bone involvement alone was seen in 6 patients with polyostotic dysplasia. Apart from the head and neck bones, femur and humerus were the only other bones found involved in the lesions. Femoral involvement alone was noted in 2 patients, and humeral and femoral involvement were seen in 2 others with polyostotic fibrous dysplasia. Fibrous dysplasia of the frontal sinus and zygoma was seen in 1 patient (Table 3). The most common presentation of fibrous dysplasia was facial deformity (100%; n = 19). Other presentations included CN involvement (15.7%; n = 3), proptosis (10.5%; n = 2), headache (5.2%; n = 1), and vertigo (5.2%; n = 1). CN involvement presented as anosmia (CN I), facial hypoesthesia (CN V), and sensorineural hearing loss (CN VIII). The Table 2. Bone involvement pattern in patients with monostotic fibrous dysplasia. Bones
No. of cases (n = 9)
Frontal Ethmoid Maxilla Zygoma Mandible Temporal Nasal
1 0 1 2 2 2 1
Table 3. Bone involvement pattern in patients with polyostotic fibrous dysplasia. Bones
No. of cases (n = 10)
Frontal and zygoma Frontal and ethmoid Maxilla and nasal Temporal and zygoma Maxilla and mandible and femur Maxilla and femur and humerus Temporal and femur and humerus Maxilla and femur
1 2 2 1 1 1 1 1
Asian J Oral Maxillofac Surg. Vol 19, No 2, 2007
Sazgar, Hassanabadi, Radji, et al
Table 4. Time interval between 2 surgeries among patients needing more than 1 operation. Time between 2 surgeries (years)
No. of cases (n = 10)
1 2 3
5 2 3
incidence of monostotic and polyostotic forms was the same and none of the patients had McCune Albright syndrome. The average time between onset of symptoms and disease diagnosis was 20 months in patients with polyostotic dysplasia and 15 months in those with monostotic dysplasia, with no normal distribution in the 2 groups. Nine patients required 1 surgical operation (monostotic dysplasia, n = 6; polyostotic dysplasia, n = 3); 2 patients with polyostotic dysplasia had frontal and ethmoidal involvement, while the other had maxillary and lateral nasal involvement. Ten cases needed 2 surgical procedures (monostotic dysplasia, n = 3; polyostotic dysplasia, n = 7); 4 patients with polyostotic dysplasia had femoral and humeral involvement besides facial bone lesions (Table 4). Surgical operations were either remodelling procedures (n = 14) or total and partial resections (n = 5). A 15-year-old boy with polyostotic dysplasia (maxillary, mandibular, and femoral involvement) developed surgical complications, such as wound infection and osteomyelitis that underwent resection of the infectious area.
Discussion Fibrous dysplasia is a benign, intramedullary, fibro-osseous lesion that most probably has a genetic origin in which normal bone is replaced with fibrotic tissue and disorganised bone trabeculae. Although the disease has shown no gender predilection in some studies, there was a male preponderance in this study (male-to-female ratio, 3:1); the male-to-female ratio was 2:1 in another study.3 We propose that craniofacial involvement may be more frequent in males;2 however, this variant result could be due to the small sample size of the present study. Clinical presentation may occur at any age, with the majority of lesions being detected by 30 years of age.2 The mean age of presentation was 18.3 years, with most patients falling in the 11-15 years age group. Onset is typically in adolescence or late childhood, although more severe forms can arise in infancy.3 The results of this study approximated the findings of other research groups. The most common site of lesion was the maxillary bone, followed by the frontal, zygoma, and temporal bones. In contrast, Van Tilburg et al13 analysed skull lesions and noted that frontal bone involvement was the most common, followed by the sphenoid, ethmoid, parietal, temporal, and occipital bones. Another study also found the ethmoid to be Asian J Oral Maxillofac Surg. Vol 19, No 2, 2007
the most commonly involved bone, followed by the sphenoid, frontal, maxilla, temporal, parietal, and occipital bones.3 The most common symptoms were facial deformity, CN involvement, proptosis, headache, and vertigo. According to another study, atypical facial pain and headache were the most common presenting features, followed by symptoms suggestive of sinusitis.3 Studies of a different group showed that patients presented more often with headache and facial asymmetry due to the enlargement of facial bones.14 Painless proptosis is not uncommon. Visual dysfunction and optic atrophy can also occur in lesions involving the sphenoid wing that encroach upon the optic canal. The most common form of maxillofacial fibrous dysplasia observed in the present study was monostotic;2,15 however, another study has reported that while craniofacial bone involvement was typically seen in approximately 10% of cases with monostotic dysplasia and 50% of cases with polyostotic form, craniofacial involvement could occur in 100% of patients with severe polyostotic dysplasia.3 The incidence of monostotic and polyostotic forms was approximately the same. In conclusion, maxillofacial fibrous dysplasia in Iran shows a male preponderance. Monostotic and polyostotic forms of the disease are almost equally prevalent. Onset is typically seen in adolescence or late childhood. The maxilla is the most common site of lesion and facial deformity is the most common presentation. Surgery is the most common treatment.
References 1.
Adada B, Al-Mefty O. Fibrous dysplasia of the clivus. Neurosurgery. 2003;52:318-22.
2.
DiCaprio MR, Enneking WF. Fibrous dysplasia. Pathophysiology,
3.
Lustig LR, Holliday MJ, McCarthy EF, Nager GT. Fibrous dysplasia
evaluation, and treatment. J Bone Joint Surg Am. 2005;87:1848-64. involving the skull base and temporal bone. Arch Otolaryngol Head Neck Surg. 2001;127:1239-47. 4.
Jan M, Dweik A, Destrieux C, Djebbari Y. Fronto-orbital sphenoidal fibrous dysplasia. Neurosurgery. 1994;34:544-7.
5.
Som PM, Brandwein M, Curtin HD, editors. Head and neck imaging.
6.
Nager GT, Holliday MJ. Fibrous dysplasia of the temporal bone: update
St Louis, MO: Mosby; 2003. with case reports. Ann Otol Rhinol Laryngol. 1984;93:630-3. 7.
Brodish BN, Morgan CE, Sillers MJ. Endoscopic resection of fibroosseous lesions of the paranasal sinuses. Am J Rhinol. 1999;13:111-6.
8.
Fitzpatrick KA, Taljanovic MS, Speer DP, Graham AR, Jacobson JA, Barnes GR, et al. Imaging findings of fibrous dysplasia with histopathologic and intraoperative correlation. AJR Am J Roentgenol. 2004;182:1389-98.
9.
Zhibin Y, Quanyong L, Libo C, Jun Z, Hankui L, Jifang Z, et al. The role of radionuclide bone scintigraphy in fibrous dysplasia of bone. Clin Nucl Med. 2004;29:177-80.
10. Harris WH, Dudley HR Jr, Barry RJ. The natural history of fibrous
103
Maxillofacial Fibrous Dysplasia in Iran
dysplasia. An orthopaedic, pathological, and roentgenographic study. J Bone Joint Surg Am. 1962;44:207-33. 11. Ruggieri P, Sim FH, Bond JR, Unni KK. Malignancies in fibrous dysplasia. Cancer. 1994;73:1411-24. 12. Yabut SM Jr, Kenan S, Sissons HA, Lewis MM. Malignant transformation of fibrous dysplasia. A case report and review of the literature. Clin Orthop Relat Res. 1988;228:281-9. 13. Van Tilburg W. Fibrous dysplasia. In: Vinken PJ, Bruyn GW, editors.
104
Handbook of clinical neurology. Vol 14. Amsterdam: North Holland Publishing Co.; 1972. 14. Mahapatra AK, Gupta PK, Ravi RR. Craniofacial surgery and optic canal decompression in adult fibrous dysplasia. Neurol India. 2003;51:123-4. 15. Morrissey DD, Talbot JM, Schleuning AJ 2nd. Fibrous dysplasia of the temporal bone: reversal of sensorineural hearing loss after decompression of the internal auditory canal. Laryngoscope. 1997;107:1336-40.
Asian J Oral Maxillofac Surg. Vol 19, No 2, 2007