Fibrous dysplasia of the facial bones. A CT study

The authors report 7 cases of fibrous dysplasia of the facial bones which were evaluated with CT. The involvement of the facial bones by fibrous dysplasia is an uncommon event, which causes different syndromes according to the extent of bone invasion. In all the cases occurred to our observation CT allowed an exact spatial evaluation of the dysplasia, and therefore a correct surgical planning. Moreover, CT densitometric values and CT appearance of fibrous dysplasia often suggested the correct diagnosis.     

Gallium-67 uptake in fibrous dysplasia of the bone

In a 43-year-old woman with fibrous dysplasia of the ribs and facial bone and in a 40-year-old man with fibrous dysplasia of the facial bone, there were considerable increases in the uptake of Tc-99m methylenediphosphonate (Tc-99m MDP) and Gallium-67 citrate. Fibrous dysplasia should be added to differential diagnosis of high Gallium-67 citrate uptake in the bone lesions.     

Maxillofacial fibrous dysplasia: personal experience with gadoliniumenhanced magnetic resonance imaging

PURPOSE: The authors sought to identify radiological criteria assisting in the diagnosis of craniofacial fibrous dysplasia and differential diagnosis of fibro-osseous lesions by comparing computed tomography (CT) and magnetic resonance imaging (MRI) findings and histological results in 23 patients with presumed fibrous dysplasia. MATERIALS AND METHODS: From February 2000 to March 2005, 23 patients (17 women and six men, aged 9-66 years) with facial bone disease underwent CT and MRI studies. Imaging findings were compared with the results of histological examination performed within 1 month of the radiological diagnosis. RESULTS: The combination of CT and MRI led to a presumptive diagnosis of fibrous dysplasia in all cases, but histology confirmed the diagnosis in 18 cases only. In two cases that had initially been considered cyst-like variants of fibrous dysplasia and were associated with irregular enhancement at MRI, histology characterised the lesions as single locations of multiple myeloma. In one case, targeted biopsy of areas showing intense enhancement led to a diagnosis of low-grade fibrosarcoma; in the remaining two cases, the definitive diagnoses were ossifying fibroma and myeloproliferative disease. CONCLUSIONS: MRI proved useful in differentiating fibrous dysplasia from other bone diseases, defining clinical behaviour, identifying neoplastic foci within dysplastic tissue and distinguishing benign from malignant bone lesions. The authors suggest a broader use of contrast-enhanced MRI for the diagnosis and follow-up of dysplastic lesions of the facial bones and for planning appropriate surgical treatment.     

McCune-Albright syndrome: the patterns of scintigraphic abnormalities

This study of 22 patients with the McCune-Albright syndrome examined the scintigraphic distribution of fibrous dysplasia. The most frequently affected areas were the base of the skull (82% of patients), mandible (50%), facial bones (45%), femora (59%), and legs (64%). The least frequently affected areas included the hands (none), wrists (none), ankles (none), feet (5%), sacrum (5%), and vertebrae (9%). The distribution varied somewhat from idiopathic fibrous dysplasia but generally agreed with the distributions reported in radiographic studies of patients with the McCune-Albright Syndrome. The serum alkaline phosphatase was not an accurate predictor of the extent of fibrous dysplasia.     

Orbitocranial asymmetry.

Eleven cases are chosen to illustrate the differential diagnosis of deforming lesions of the bony orbit and its vicinity, which cause unilateral proptosis or other cranio-facial disfigurement. Three distinct varieties of orbito-cranial neurofibromatosis are distinguished, and they are contrasted with other deforming lesions of childhood--unilateral craniosynostosis, chronic juvenile subdural hygroma of the temporal fossa and congenital facial hemihypertrophy. Adult lesions are represented by intrinisic tumours of the orbit and paranasal sinuses, and by the commonest two processes deforming the sphenoid bone, meningioma and osseous fibrous dysplasia.     

Positive gallium-67 citrate uptake in a patient with polyostotic fibrous dysplasia

Fibrous dysplasia is an uncommon bone condition with characteristic radiologic features. It is well known that there is increased uptake of Tc-99m hydroxymethylene diphosphonate (HMDP) and methylene diphosphonate (MDP) in fibrous dysplasia. There are no reports of uptake of Ga-67 citrate by fibrous dysplasia. A case is reported in which positive Ga-67 uptake was seen in a patient with polyostotic fibrous dysplasia.     

Polyostotic fibrous dysplasia (McCune-Albright) with rare multiple epiphyseal lesions in association with aneurysmal bone cyst and pathologic fracture

Fibrous dysplasia, including McCune-Albright syndrome, is a genetic, non-inheritable benign bone disorder that may involve a single or multiple bone, typically occurring in the diaphysis or the metaphysis of long bones. In very rare instances polyostotic fibrous dysplasia present involvement of the epiphysis in long bones. Aneurysmal bone cysts are benign, expansile, lytic bone lesions formed by cystic cavities containing blood, that may occur de novo or secondary to other lesions of bone, including fibrous dysplasia. We report a case of an 18-year-old female with polyostotic fibrous dysplasia (McCune-Albright syndrome) with diaphyseal and unusual multiple foci of epiphyseal involvement of long bones as well as in the patella, and a simultaneous aneurysmal bone cyst of the left femoral neck with pathologic fracture. This is the first report of a simultaneous aneurysmal bone cyst in a patient with polyostotic fibrous dysplasia (McCune-Albright syndrome) with involvement of diaphysis and epiphysis of long bones, highlighting that fibrous dysplasia should be included in the differential diagnosis of polyostotic tumors involving the diaphysis as well as the epiphysis. In patients with polyostotic fibrous dysplasia there should be an active search for lesions in the epiphysis.     

Malignant transformation of fibrous dysplasia into chondroblastic osteosarcoma

A case of malignant transformation of polyostotic fibrous dysplasia into maxillary chondroblastic osteosarcoma is presented. The clinical, radiographic, CT, MR imaging features and pathological findings of polyostotic fibrous dysplasia and its malignant transformation are described. Malignant transformation of fibrous dysplasia is rare and has not previously been described in the English literature in this location in McCune-Albright syndrome and in the absence of radiation treatment.     

颌面部骨纤维结构不良的X线诊断和鉴别诊断

A radiologic-pathologic correlative study was carried out on 43 cases with fibrous dysplasia of the facial bones with emphasis on basis for radiological diagnosis. The x-ray manifestations according to density changes are classified into three types: sclerotic, osteolytic and mixed. The lesion extends along the longitudinal axis in the mandible whereas in the maxilla, the lesion spreads in a diffuse pattern along the wall of the maxillary antrum with preservation of maxillary contour. The authors considered that fibrodysplasia and ossifying fibroma are different disease entities and should be distinguished by combination of clinical, radiologic and pathologic evidences.     

Fibrous dysplasia with barely increased uptake on bone scan: a case report

Fibrous dysplasia, in general, appears as an area of markedly increased uptake on bone scintigraphy. Therefore, the possibility of fibrous dysplasia is likely to be excluded when the lesion shows no or slightly increased uptake. The authors report a case of incidentally detected fibrous dysplasia that appeared as slightly increased uptake on bone scintigraphy and was found to harbor a bone infarction along with typical fibrous dysplasia by pathologic examination of a specimen sampled by curettage. Barely increased bone uptake in fibrous dysplasia may be associated with decreased vascularity and osteoblast activity of the lesion as a result of concurrent bone infarction. The authors suggest that not every case of fibrous dysplasia appears as an area of intensely increased uptake on a bone scan. Clinicians should be cautious in interpreting bone scans of radiographically indicated fibrous dysplasia.     

Osteosarcoma in fibrous dysplasia

Two cases are reported with osteosarcomatous transformation in fibrous dysplasia, one in the skull and one in the iliac bone. In both cases the patient was known to have longstanding polyostotic fibrous dysplasia; no radiation therapy was ever given. The incidence of sarcomatous transformation in fibrous dysplasia in the files of the Netherlands Committee on Bone Tumours is 0.5%. When strict criteria for spontaneous malignant transformation are used, the actual incidence is probably lower than is suggested.     

Scintigraphic evaluation of polyostotic fibrous dysplasia

Bone scintigraphy is a sensitive imaging modality for detecting early lesions and polyostotic involvement in fibrous dysplasia. Common findings include multiple areas of focal uptake that are often unilateral and typically involve the ribs, tibia, femur, and craniofacial bones. A knowledge of various skeletal manifestations of fibrous dysplasia is helpful to distinguish it from Paget's disease, osteoblastic metastasis, and fractures. Several recent cases representing varying involvement of fibrous dysplasia are presented and the literature is reviewed.     

Fibro-osseous lesions of the face and jaws

Maxillofacial fibro-osseous lesions (FOL) consists of lesions that differ, with the exception of fibrous dysplasia, to those found in the rest of the skeleton. FOLs of the face and jaws are cemento-ossifying dysplasia, fibrous dysplasia and cemento-ossifying fibroma. Radiology is central to their diagnosis because the pathology for all FOLs is similar, although they range widely in behaviour, from dysplasia, hamartoma to benign neoplasia with occasional recurrence. Furthermore, once diagnosed the management of each is different. For cemento-ossifying dysplasia, this may mean doing nothing, simply because no treatment is generally appropriate. Almost all cemento-ossifying fibromas should be treated surgically, whereas cases of fibrous dysplasia are treated according to their clinical presentation, ranging from review and follow-up to surgery necessary to save the patient's sight or reduce deformity. The most important and frequent features of the FOLs differential diagnosis is discussed with assistance of a flow-chart.     

Scintigraphic manifestation of fibrous dysplasia

Scintigraphic manifestations of fibrous dysplasia were analyzed in 59 lesions of 26 patients (12 monostotic, 14 polystotic). Bone imaging with Tc-99m MDP revealed a high percentage of increased uptake of radioisotope in the lesions of fibrous dysplasia. Four (14%) of 29 cystic lesions and two (7%) of 30 lesions with the appearance of ground glass showed no increase in radioisotope uptake, although roentgenograms showed marked changes. Therefore, care must be taken in the diagnosis of fibrous dysplasia with bone imaging alone. Nuclear methods, however, are indispensable in evaluating the dynamic aspects of bone mineral behavior and in demonstrating disease where none was suspected, or in visualizing polyostotic involvement in those cases where only monostotic disease was suspected clinically. It is concluded that both scintigrams and roentgenograms are complementary procedures in the diagnosis of fibrous dysplasia.     

面神经管病变的多层螺旋CT评价

目的:分析面神经管病变CT表现,评价多层螺旋CT的临床价值。方法:回顾性分析面神经管病变患者35例CT资料,男24例,女11例,年龄4～51岁,平均27岁,所有患者均行多层螺旋CT扫描,常规行多平面重建和面神经管曲面重建。结果:面神经管骨折15例,其中鼓室段骨折8例,乳突段骨折5例,迷路段骨折2例;胆脂瘤型中耳炎侵犯面神经管15例;面神经瘤1例,乳突段面神经管前移2例,颞骨骨纤维异常增殖症累及面神经管2例。结论:多层螺旋CT及后处理成像能清晰显示面神经管病变,对临床诊断和治疗有重要价值。     

骨纤维异常增殖症自发恶变15例分析

报告１５例骨纤维异常增殖症（简称骨纤）自发恶变，其中恶变为骨肉瘤８例，纤维肉瘤５例和软骨肉瘤２例。１５例均长期患有骨纤，均未接受过放射治疗。本组恶变者中，多骨型骨纤１１例，单骨型４例。恶变患者的主要临床症状是病变区疼痛和肿胀，而后则出现硬性肿块。恶变的Ｘ线表现为：在原骨纤病变区域内，出现虫噬样或囊状溶骨性破坏，骨纤病变边缘变模糊或消失，皮质破坏并逐渐出现软组织肿块。恶变为骨肉瘤者，肿瘤区内常有不同形态的痛骨；软骨肉瘤则可见环状或斑片状钙化；纤维肉瘤则表现为单纯溶骨性破坏，软组织肿块呈中等密度。     

颞骨骨纤维异常增殖症HRCT研究

目的 探讨颞骨骨纤维异常增殖症HRCT表现，评价HRCT 的诊断价值。资料与方法回顾性分析资料完整的16例颞骨骨纤维异常增殖症的HRCT扫描图像。结果 颞骨单侧发病lO例，双侧发病6例。腿cT示受累颞骨弥漫性膨大，骨皮质变薄。根据病变的密度分为3种类型：硬化型9例(56．25％)，表现为均匀一致的高密度；变形性骨炎型6例(37．5％)，表现为高密度病灶中散在点或片状低密度区；囊型1例(6．25％)，病变明显膨胀，表现为多个球形或卵圆形透亮区，有薄的骨壳包绕。骨纤维异常增殖症可导致颞骨的自然腔隙、孔道狭窄，如外耳道、鼓室腔、内听道、前庭导水管、耳蜗导水管及面神经乳突段骨管；一般不破坏听小骨和内耳骨迷路；常见并发症为炎症、胆脂瘤，3例(18．75％)继发胆脂瘤分别位于外耳道、乳突及上鼓室，乳突窦，其中上鼓室，乳突窦胆脂瘤破坏邻近听小骨、上半规管。此外，还可引起岩段颈内动脉管、颈静脉孔、茎乳孔和颞下颌关节形态的改变。结论HRCT可清楚显示颞骨骨纤维异常增殖症骨质改变、病变范围及并发症，在本病的诊断、治疗及随访中起重要作用。     

Fibrous dysplasia vs adamantinoma of the tibia: differentiation based on discriminant analysis of clinical and plain film findings

Differentiation between benign fibrous dysplasia and malignant adamantinoma of the tibia is challenging because of the impact the diagnosis has on the choice of treatment (none or extensive surgery). The histologic and pathologic similarities of the lesions and the controversial relationship between fibrous dysplasia, osteofibrous dysplasia, and adamantinoma complicate the matter. We found a large overlap of histologic features in lesions considered either fibrous dysplasia or osteofibrous dysplasia on the basis of the radiologic findings. The purpose of this study was to determine the value of the plain radiograph of the lower leg in combination with clinical findings to differentiate the benign from the malignant condition. The clinical symptoms, radiographs, and histologic slides of 46 patients with fibrous dysplasia and 22 with adamantinoma in the tibia were reviewed retrospectively. In only one of 12 patients with radiologic or histologic characteristics of osteofibrous dysplasia were both radiologic and histologic criteria for the diagnosis present. A linear discriminant analysis was performed on six clinical (age, spontaneous pain, pain after trauma, swelling only, pain and swelling, and bowing deformity) and 25 radiologic signs. Fibrous dysplasia and its variant osteofibrous dysplasia could be identified correctly in 87% (40 of 46 patients) and adamantinoma in 95% (21 of 22 patients) by using the patient's age and four radiologic signs. When results from the discriminant analysis of a randomized subgroup of patients (32) were used on the other subgroup (36 patients), fibrous dysplasia was correctly identified in 84% (21 of 25) and adamantinoma in 82% (nine of 11). Fibrous dysplasia is more prevalent than adamantinoma in a young patient, when radiographs show a ground-glass appearance and anterior bowing and when there is no multilayered periosteal reaction and moth-eaten destruction. When radiologic signs and the patient's age are combined, fibrous dysplasia and adamantinoma can be discriminated in a high percentage of patients.     

The appearance of Mazabraud’s syndrome on <Superscript>18</Superscript>F-FDG PET/CT

Mazabraud’s syndrome is a rare disorder, the main characteristics of which are fibrous dysplasia of bone associated with intramuscular myxomas. The metabolic characteristics of intramuscular myxomas, associated with fibrous dysplasia, have not previously been described with ¹⁸F-FDG-PET. Our case demonstrates that there is low, but not insignificant uptake associated with these intramuscular myxomas, with a standardized uptake value (SUV) range between 1.3 and 2.6. As such, this entity merits consideration when evaluating hypoattenuating intramuscular masses, particularly in the context of fibrous dysplasia.     

Three-dimensional CT reformation in children

Three-dimensional computed tomographic (CT) reformation has proven useful in the evaluation of congenital malformations of the brain as well as in the surgical approach and postoperative assessment of craniofacial anomalies in children. This technique was performed on 41 patients, of whom eight are presented. The congenital anomalies of semilobar holoprosencephaly and colpocephaly are described. Six representative cases of craniofacial anomalies with pre- and postoperative examinations include Crouzon syndrome, orbital fibrous dysplasia, frontonasal encephalocele, cranial involvement from neurofibromatosis, Treacher-Collins syndrome, and a Tessier III facial cleft. Addition of the dimension of depth provides a view heretofore not obtainable by standard imaging techniques and allows more accurate diagnosis as well as a more specific approach to surgical planning and follow-up.