CRANIOFACIAL FIBROUS DYSPLASIA : A CASE REPORT

Dr Vaibhav L.R. Fibrous dysplasia is a developmental tumor like condition that is characterized by replacement of normal bone by excessive proliferation of cellular fibrous connective tissue intermixed with irregular bony trabeculae. caused by sporadic, congenital mutations in the cAMP regulating protein, Gsα. Craniofacial form is a type of fibrous dysplasia, occurs in association with monostotic or polyostotic form can also occur in an isolated pattern. Here a case of craniofacial fibrous dysplasia has reported.


Dr Vaibhav L.R.
Fibrous dysplasia is a developmental tumor like condition that is characterized by replacement of normal bone by excessive proliferation of cellular fibrous connective tissue intermixed with irregular bony trabeculae. caused by sporadic, congenital mutations in the cAMP regulating protein, Gsα. Craniofacial form is a type of fibrous dysplasia, occurs in association with monostotic or polyostotic form can also occur in an isolated pattern. Here a case of craniofacial fibrous dysplasia has reported.
Case report:-  A 11 year old male patient reported to our department with complaint of swelling in the right side of the face noticed since 3 months. Initially swelling was small and gradually increased to present size. On extra oral examination diffused swelling of about 3*4 cm was present on right side of the face extending superioinferiorly 1 cm below the cantho tragus line; to line joining corner of mouth to tragus and anteroposteriorly 1 cm away from the corner of the mouth to 1 cm in front of right tragus. On palpation the consistency was bony hard, nontender, and no local rise in temperature. Intraorally swelling was present extending bucally from right upper deciduous canine to beyond right tuberosity. Labiopalatal dimension at premolar region was about 2 cm. Buccal and palatal cortical plates were expanded. Overlying mucosa appeared normal, firm,and was non-tender. Laboratory investigations were normal except for a raised serum alkaline phosphatise level which was 309IU/L. Radiological investigations includes maxillary occlusal view, orthopantomogram(OPG), and CT Scan and bone scan.
Maxillary occlusal view and OPG shows gross radiopacity in the maxillary bone from first premolar region to posterior to tuberosity region, which gives ground glass appearance.
CT image shows a radio opaque lesion occupies most of the facial bones in the mid and upper facial skeleton on the right side, which is significantly expanded. The maxillary sinus and nasal airway on the right is obliterated   1706

Discussion:-
Fibrous dysplasia is a bone disorder characterized by slow progressive replacement of medullary bone by abnormal proliferative isomorphic fibrous tissue with classic ground glass appearance [4] . Fibrous dysplasia has 4 different disease patterns Monostotic (70%), Polyostotic (30%), Craniofacial form and Cherubism(rare) [3,6] . The range of skeletal involvement varies from an asymptomatic to progressive functional deficit & aesthetic problems. The clinical severity depends on time when the mutation of GNAS-1 occurs.
Monostotic Form: If mutation occurs during postnatal life the progeny of that mutated cells are essentially confined to one site resulting in fibrous dysplasia affecting a single bone. About 70% cases are of monostotic form and they involve mainly ribs, femur, tibia & craniofacial bones [4,5,6] .
Polyostotic Form: It is seen if mutation occurs during 6th week of intrauterine life. Multiple bones may get involved. This form commonly involves the skull & facial bones, pelvis, spine & shoulder girdle. Femur shows shephered's crook deformity [6] . Polyostotic form is again sub-classified into Jaffe's type & Albright syndrome. Polyostotic fibrous dysplasia with soft tissue called mazabraud syndrome [7] .
Craniofacial Form: 50%-100% of patient with polyostotic disease & 10% patient with monostotic disease have craniofacial involvement [1,4] . Maxilla is more commonly involved than mandible [4] . When maxilla is affected it may involve zygomatic & sphenoid bone. Involvement of frontal, sphenoid, naso-ethmoid & maxillary bone may lead to nasal obstruction, sinus obstruction & sinusitis [4] . Hypertelorism, cranial asymmetry, facial deformity, visual impairment, exophthalmos and blindness may occur due to involvement of orbital and parietal bone [6] . Malignant changes with fibrous dysplasia include Osteosarcoma, Fibrosarcoma, Chondrosarcoma, Malignant fibrous histiocytoma & Ewings sarcoma [4] . Association of Amelobastoma, Cystic degeneration, Angiosarcoma [8] , Frontal sinus mucocele [9] have also reported. Treatment is primarily surgery. When the only tooth bearing area is involved conservative treatment is bone shaving. Use of Calcitonin & Pamindronate is also reported for its treatment [10] . Biopsy can be taken to rule out the lesion. Fibrous dysplasia usually get stabilized after puberty.   1707 Cherubism: It is a special variant of fibrous dysplasia is also known as familial fibrous dysplasia. It is an autosomal dominant disorder of variable penetrance, with onset in childhood and is typically more severe in males [11] .

Conclusion:-
Fibrous dysplasia is a difficult disease to manage. The sporadic mosaic nature of the disease means that it is an uncommon disease with a variable expression. Hence managing the outcome of this disease is challenging. In the future, we can look to new medical treatments that are on the horizon, and should work for the initiation of international collaborative studies to better define optimal surgical approaches to the treatment of this challenging disease.