Imaging of craniofacial fibrous dysplasia

Whole Exome Sequencing as an Effective Molecular Diagnosis Tool for Craniofacial Fibrous Dysplasia with Ocular Complications

PURPOSE

To summarize the clinical manifestations of craniofacial fibrous dysplasia (CFD) patients with ocular complications, and find effective methods to diagnose early.

METHODS

Nine CFD patients with ocular complications, and their parents were recruited in this study. All patients underwent ocular and systemic examinations. Bone lesions from all patients and peripheral blood from patients and their parents were collected for whole exome sequencing (WES). According to the screening for low-frequency deleterious variants, and bioinformatics variants prediction software, possible disease-causing variants were found in multiple CFD patients. The variants were validated by Sanger sequencing. Trio analysis was performed to verify the genetic patterns of CFD.

RESULTS

All patients were diagnosed with CFD, according to the clinical manifestations, classic radiographic appearance, and pathological biopsy. The main symptoms of the 9 CFD patients, included visual decline (9/9), craniofacial deformity (3/9) and strabismus (2/9), with few extraocular manifestations. The family backgrounds of all the CFD patients indicated that only the patient was affected, and their immediate family members were normal. GNAS variants were identified in all bone lesions from CFD patients, including two variant types: c.601C > T:p.R201C(6/9) and c.602G > A:p.R201H (3/9) in exon 8. The detection rate reached 100% by WES, but only 77.8% by Sanger sequencing. Interestingly, we found GNAS variants could not be detected in peripheral blood samples from CFD patients or their parents, and other potentially disease-causing gene variants related to CFD were not found.

CONCLUSIONS

For CFD patients with bone lesions involving the optic canal or sphenoid sinus regions, ocular symptoms should also be considered. Furthermore, we confirmed that CFD is not inherited, somatic variants in the GNAS gene are the main pathogenic gene causing CFD. Compared to the traditional methods in molecular genetic diagnosis of CFD, WES is more feasible and effective but limited in the type of samples.

Craniofacial Fibrous Dysplasia in Fronto-Orbital Region: A Single-Center Retrospective Study of 38 Cases

OBJECTIVE

This study presents the clinical characteristics, imaging manifestations, and surgical experience in 38 patients diagnosed with craniofacial fibrous dysplasia in fronto-orbital region (foFD).

METHODS

We retrospectively analyzed the clinical data from 38 patients who had surgery for foFD. The surgical procedure typically involved extensive tumor removal, followed by immediate reconstruction of the frontal bone and orbit using synthetic materials. Additionally, 9 patients underwent simultaneous microscopic decompression of the optic canal.

RESULTS

Common clinical manifestations included progressive fronto-orbital bone deformity (35), proptosis (28), orbital dystopia (21), and visual impairment (9). The disease primarily affecting the frontal bone (38), the sphenoid bone (28), and the ethmoid bone (24). The optic canal was involved in 9 patients with functional impairment. Computed tomography scans in all 38 cases revealed satisfactory repair material positioning and complete resolution of frontal deformities. Among the 9 patients who underwent optic canal decompression, 7 experienced partial recovery of visual acuity after surgery.

CONCLUSIONS

In the surgical treatment of foFD, it is crucial to achieve maximal bone resection and repair skull defects, while decompressing the optic canal can provide significant benefits for patients with decreased visual function preoperatively. The use of preformed artificial materials offers advantages in aesthetic restoration after lesion excision.

Fibrous Dysplasia of the Jaw: Advances in Imaging and Treatment

A total of 7% of all benign bone lesions are diagnosed as fibrous dysplasia (FD). The symptoms of FD of the jaw range from asymptomatic to dental anomalies, pain and facial asymmetry. Due to its resemblance to other fibro-osseous bone lesions, misdiagnosis often occurs and can lead to inadequate treatment. Particularly in the jaw, this lesion does not become quiescent during puberty, making fundamental knowledge about the diagnosis and treatment of FD crucial. Mutational analysis and nonsurgical approaches offer new diagnostic and therapeutic options. In this review, we examine the advances and the difficulties of the diagnosis and the various treatment modalities of FD of the jaw in order to capture the current scientific knowledge on this bone disease.

Current concepts of craniofacial fibrous dysplasia: pathophysiology and treatment

Fibrous dysplasia is an uncommon genetic disorder in which bone is replaced by immature bone and fibrous tissue, manifesting as slowgrowing lesions. Sporadic post-zygotic activating mutations in GNAS gene result in dysregulated GαS-protein signaling and elevation of cyclic adenosine monophosphate in affected tissues. This condition has a broad clinical spectrum, ranging from insignificant solitary lesions to severe disease. The craniofacial area is the most common site of fibrous dysplasia, and nine out of 10 patients with fibrous dysplasia affecting the craniofacial bones present before the age of 5. Surgery is the mainstay of treatment, but the technique varies according to the location and severity of the lesion and associated symptoms. The timing and indications of surgery should be carefully chosen with multidisciplinary consultations and a patient-specific approach.

Malignant Sarcomatous Degeneration of Craniofacial Fibrous Dysplasia

BACKGROUND

Fibrous dysplasia (FD) is an uncommon bone disease characterized by the replacement of normal bone architecture with abnormal fibro-osseous connective tissue. Here, we discuss 2 cases of craniofacial FD, with malignant sarcomatous degeneration - a rare and morbid complication of the disease.

CASE HISTORY

Two cases of craniofacial FD with malignant degeneration are presented. In the first, a 68-year-old male with a history of FD presented with acutely worsening left-sided facial pain and V2 and V3 hypoesthesia. Imaging findings suggested a large infratemporal fossa mass with biopsy demonstrating sarcomatous degeneration. Radical craniofacial resection achieved a gross total resection with likely microscopic disease. The patient was unable to tolerate adjuvant chemotherapy or radiation and succumbed to his disease 13 months following surgery.In the second case, a 36-year-old male with McCune-Albright Syndrome and craniofacial FD presented with acutely worsening left-sided headaches and midface hypoesthesia. Imaging revealed a heterogenous and expansile lesion with erosive changes in the left nasal cavity and infratemporal fossa. Pathology was suggestive of low grade sarcomatous degeneration. Given the extensive involvement of the skull base, the tumor was deemed unresectable, and the patient soon died following initiation of chemotherapy.

CLINICAL RELEVANCE

Malignant sarcomatous transformation is a rare and challenging complication of craniofacial FD. Indolent onset, advanced spread at time of presentation, and close relationship with vital neurovascular structures are all hurdles for the treating clinician. The entity poses a diagnostic dilemma, as pathological analysis can be equivocal and may mimic nonmalignant processes, such as locally aggressive FD.

Imaging of pediatric nasal masses: A review

Several conditions may present as nasal masses in pediatric age, including congenital and developmental disorders, inflammatory and infectious conditions, neoplastic and neoplastic-like lesions, and other miscellaneous disorders. A confident presurgical diagnosis can be challenging and imaging is often key in the management of these lesions. We provide a pictorial review of pediatric nasal masses and discuss a location-based approach to the diagnosis of these lesions on imaging studies. Acquaintance with the most common pathologies and awareness for its characteristic imaging features can aid the physician in the differential diagnosis. Location and extension of the lesion can be particularly helpful. Midline masses raise suspicion for developmental nasal midline lesions, including frontoethmoidal cephalocele, dermoid/epidermoid cyst, and neuroglial heterotopia. In case of trauma, nasal septum hematoma/abscess should be considered. Developmental or odontogenic cystic lesions and osseous neoplasms and neoplasm-like lesions can originate from the maxilla and palate. Although most nasal tumors show overlapping imaging characteristics, some have suggestive features, such as nasopharyngeal angiofibroma and esthesioneuroblastoma. Malignant tumors tend to be locally aggressive, demonstrating invasive features, bony erosion, intermediate signal on T2-weighted images, and restricted diffusion on diffusion-weighted imaging. In certain cases, a definite diagnosis can only be made histologically. Nonetheless, detailed characterization of the lesion is crucial prior to invasive procedures in order to avoid complications.

Imaging technologies in the differential diagnosis and follow-up of brown tumor in primary hyperparathyroidism: Case report and review of the literature

Brown tumors are osteolytic lesions associated with hyperparathyroidism (HPT). They may involve various skeletal segments, but rarely the cranio-facial bones. We report a case of a young boy with a swelling of the jaw secondary to a brown tumor presenting as the first manifestation of primary HPT (PHPT). He was found to have brown tumor located in the skull, as well. Different imaging technologies were employed for the diagnosis and follow-up after parathyroidectomy. We enclose a review of the literature on the employment of such imaging technologies in the differential diagnosis of osteolytic lesions. A multidisciplinary approach comprising clinical, laboratory and imaging findings is essential for the differential diagnosis of brown tumor in PHPT.

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Brown tumors are associated with more severe hyperparathyroidism (HPT).

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The case of a young patient with primary HPT and brown tumors is reported.

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A multidisciplinary approach should be employed for the differential diagnosis.

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We reviewed the main radiological characteristics of different types of osteolytic lesions.

Management of the Temporal Bone Fibrous Dysplasia With External Auditory Canal Stenosis and Secondary Cholesteatoma in an Asian Population: A 11-Case Series

OBJECTIVE

This article summarizes the experience of diagnosis and treatment of temporal bone fibrous dysplasia (FD) with external auditory canal (EAC) stenosis and secondary cholesteatoma in the Chinese population, in order to improve the quality of life of patients in the future.

METHODS

Eleven patients with FD of the temporal bone who underwent surgery were retrospectively reviewed.

RESULTS

All lesions originated from the temporal bone, and all involved of the EAC. There were 11 cases of cholesteatoma in the EAC, 4 cases of cholesteatoma in the middle ear. The most common symptoms were hearing loss (100%), tinnitus (36.4%), and otorrhea (36.4%). Two patients were severe-profound sensorineural hearing loss, and one patient was complicated with subperiosteal abscesses. All 11 patients underwent surgery. There were no perioperative complications in this series and median follow-up time was 4.2 years.

CONCLUSION

Temporal bone FD remains a rare diagnosis, especially in the Asian population. The lesions mainly lead to stenosis of the EAC, especially at the osteochondral junction. Cholesteatoma is the main complication of this disease, which is secondary to occlusion of the EAC with the growth of the lesion. Canaloplasty of EAC combined with wide meatoplasty can provide excellent prognosis in most cases.

Large solitary lytic skull vault lesions in adults: radiological review with pathological correlation

The diagnosis of a large solitary lytic skull vault lesion in adults is a challenge due to variable aggressiveness and overlapping features. The purpose of this article is to demonstrate the use of an imaging approach to narrow the differential diagnosis when a large solitary lytic skull vault lesion is encountered. The initial imaging assessment using computed tomography (CT) is invaluable in determining lesion aggressiveness based on bony margins and skull tables involvement. Further assessment with magnetic resonance (MR) imaging including diffusion weighted imaging (DWI) aids in soft tissue characterization. We present cases of large solitary lytic skull vault lesions in adults, emphasizing on salient and atypical imaging features, with pathological correlation for better understanding of the disease processes that underlie the imaging features.

The surgical management of monostotic fibrous dysplasia of the inferior turbinate

Fibrous dysplasia is a non-neoplastic, sporadic, slowly progressing disease of the bone in which normal bone is replaced by abnormally overgrowing lesions. There are three different types of fibrous dysplasia: monostotic (affecting a single bone), poliostotic (affecting multiple bones) and syndromic, when it is associated with other diseases (such as McCune Albright syndrome). Fibrous dysplasia affects cranio-facial bones in 10% of the cases. However, its occurrence in the inferior turbinate is extremely rare. To the best of our knowledge, only four cases of monostotic form have been reported so far. Hereafter we describe a case of monostotic FD of the inferior turbinate surgically treated with a trans-nasal endoscopic partial maxillectomy type II.

An Analysis of Clinical and Histopathologic Features of Fibrous Dysplasia of the Jaws: A Series of 40 Cases and Review of Literature

Fibrous dysplasia (FD) is a rare condition commonly involving the jaws. While FD has a typical clinical and histological presentation, considerable variation exists. Moreover, overlap of features with other disorders is possible. This study serves to characterize the features of a large case series of FD of the jaws. With IRB approval, the University of Florida Oral Pathology Biopsy Service archive was retrospectively searched from 1994 to 2015 for cases of FD. Epidemiological data, location, duration, clinical and radiographic appearance, clinical impression and exact microscopic diagnosis were recorded. The average age was 37.3 years (range 7-87 years) with majority of cases in females (67.5%). The most common ethnicity was Caucasian. Maxillary location was predominant (59%), followed by mandible (38%) and multiple locations (3%). Expansion was reported in 78% of cases. Radiographically, most cases exhibited ground glass opacity, however some presented with a mottled or mixed radiopaque/radiolucent appearance. Histologically, a wide variation in terms of stromal cellularity, presence of osteoblastic rimming, and presence of calcified material mimicking cemento-osseous dysplasia was observed. Clinicians and pathologists should be cognizant of the significant variability in clinical, histopathologic, and radiographic presentation of FD, which may pose a diagnostic challenge.

Magnetic resonance imaging features of craniofacial fibrous dysplasia

Purpose

To assess the value of magnetic resonance imaging (MRI) in detecting craniofacial fibrous dysplasia (CFD) and diagnosing and differentiating it from intraosseous meningioma. Additionally, the MRI appearance of the typical computed tomography (CT) imaging feature, the ground glass phenomenon, was evaluated.

Material and methods

MRI datasets of 32 patients with CFD were analysed retrospectively. Detectability in MRI was assessed by analysis of 10 randomly selected patients with CFD and 10 normal controls by two blinded readers. Changes of affected bone, internal lesion structure, T1 and T2 signal intensity, and contrast enhancement of the lesion in general and ground glass areas in particular were assessed. Ten patients with intraosseous meningioma (one in each) served as differential diagnosis for CFD.

Results

All 10 CFD lesions were reliably detected in MRI. In 32 patients 36 CFD lesions were evaluated. In 66.7% CFD were iso- to hypointense in T1 and hyperintense in T2; this proportion was similar for ground glass areas (65.7%). Ground glass areas were more homogeneously structured than the whole CFD lesion in both T1 (100% vs. 56%, respectively) and T2 (91% vs. 61%, respectively). Contrast enhancement was found in 97% of complete CFD lesions and 93% of ground glass areas. The accuracy for CFD vs. intraosseous meningioma was 100% for 'no soft-tissue component' and 98% for 'bone broadening' in MRI.

Conclusions

Distinct morphological changes of CFD are reliably detected in MRI and allow differentiation from intraosseous meningioma. Areas with ground glass phenomenon in CT show a predominantly homogenous internal structure in MRI with contrast enhancement.

Orbital apex disorders: Imaging findings and management

Orbital apex disorders include orbital apex syndrome, superior orbital fissure syndrome and cavernous sinus syndrome. These disorders result from various etiologies, including trauma, neoplastic, developmental, infectious, inflammatory as well as vascular causes. In the past, these have been described separately based on anatomical locations of disease process; however, these three disorders share similar causes, diagnostic evaluation and management strategies. The etiology is diverse and management is directed to the causative process. This imaging review summarizes the pertinent anatomy of the orbital apex and illustrates representative pathological processes that may affect this region. The purpose of this review is to provide an update on the current status of diagnostic imaging and management of patients with orbital apex disorders.

Trends in maxillofacial imaging

Maxillofacial imaging encompasses radiology of the teeth and jaws, including the temporomandibular joints. Modalities used include intra-oral radiographs, panoramic tomography, cephalograms, cone-beam computed tomography, computed tomography, magnetic resonance imaging, ultrasound, and radionuclide imaging. Common indications for imaging are impacted and supernumerary teeth, dental implants, inflammatory dental disease, and fibro-osseous lesions, cysts, and masses of the jaws. Osteonecrosis of the jaws may follow radiotherapy or the use of bisphosphonates and other drugs. Imaging of the temporomandibular joints and the potential role of imaging in obstructive sleep apnoea are also discussed.

Fibrous dysplasia of the middle nasal turbinate: imaging and clinical significance

Two cases of fibrous dysplasia involving the middle nasal turbinate are presented. Fibrous dysplasia is a common benign fibro-osseous disease involving the flat bones, often affecting the bony structures of the skull and facial skeleton. Primary occurrence or secondary involvement of the nasal turbinate is not a common manifestation of the disease. Involvement of the inferior turbinate generally does not have specific management-related issues; however, involvement of the middle turbinate, especially the lateral lamella, can predispose to surgical morbidity during endoscopic surgical management. Clinical presentation, management and features of the disease on CT imaging are presented.

[Transpterygoid expanded endonasal approach in fibrous dysplasia of the skull base: case report and technical note]

INTRODUCTION

Expanded endonasal approaches (EEA) are becoming a first-level technique for the treatment of skull base pathologies. In some cases, the endoscopic procedures make it possible to dissect structures manipulated with greater difficulty in the classic approaches. We report a full endoscopic transpterygoid EEA for the treatment of a fibrous dysplasia (FD) of the skull base. In addition, we reviewed the English literature available on FD and transpterygoid EEA, establishing an exact surgical technique and showing our intraoperative experience.

CASE REPORT

A 42-year-old male with right sixth cranial nerve palsy. Cranial MRI and CT showed a central skull base lesion with diagnostic suspicion of FD. Patient underwent a full endoscopic transpterygoid EEA, achieving a wide skull base neurovascular decompression. Neuronavigation and the vidian canal landmark resulted mandatory during intraoperative procedure.

DISCUSSION

The transpterygoid EEA is a safe technique consistently supported in the literature. It may reduce the morbidity associated to the classic transcranial approaches, since it permits maximum resection with minimum craniofacial distortion. The vidian hole and canal are the landmarks used to locate and avoid injury to the lacerum segment of the carotid injury. The surgical treatment indication in FD cases must be established in symptomatic patients.

CONCLUSION

Transpterygoid EEA for treatment of FD of the skull base is a safe and effective procedure, thanks to the guide that the vidian canal provides in finding the lacerum segment of the carotid artery.

CT-guided percutaneous skull biopsy using a drill-assisted system: Technical report of two cases

The OnControl coaxial biopsy system (Vidacare Corporation, Shavano Park, TX) includes an inner diamond-tipped access needle and hollow biopsy needle that engage with a battery-powered hand drill. Herein, we report the use of this novel device to perform two CT-guided percutaneous skull biopsies. Both procedures were performed without complication and facilitated a pathologic diagnosis.

Benign fibrous histiocytoma of parietal bone: case report and review of the literature

A benign fibrous histiocytoma with primary site of origin in the parietal bone has not yet been reported in the literature. We report here a case concerning a 12-year-old girl with a 14-month history of an enlarging parietal bone mass. The tumor was excised after removal of the cortical bone and resection of the tumor surrounding the cortical bone erosion using pre-plasticity titanium repair. Both postoperative histopathological examination and immunohistochemical analysis were consistent with a benign fibrous histiocytoma. No clinical or computed tomography (CT) radiological signs of tumor recurrence and/or metastasis were observed at 12 months. Although a primary benign fibrous histiocytoma of the parietal bone is a rare tumor, it should be considered as a potential diagnosis for any cranial tumor. Surgical intervention is the most effective treatment technique for a benign fibrous histiocytoma.

CT and MR Imaging in a Large Series of Patients with Craniofacial Fibrous Dysplasia

Background

In this retrospective review of patients with craniofacial fibrous dysplasia (FD), the clinical and radiological findings of CT and MR scan were analyzed.

Material/Methods

The study material included 32 patients, at 9 to 68 years of age that were directed for differential diagnostics of several disorders in the head. We recorded CT and MRI data related to the lesion number, location, sidedness, appearance, and sex of the cases with craniofacial FD.

Results

Of 32 patients involved in this study, 17 had monostotic and 15 had polyostotic involvement pattern. Bones most commonly involved by monostotic involvement in females were, in descending order, mandibular, maxillary, and sphenoid bones, while the sphenoid bone was involved the most in males. Leontiasis ossea was observed in 2 patients. Sclerotic and mixed lesion types were more common in both females and males. In T1- and T2-weighted MRI sequences, hypointensity was more common compared to hyperintensity or heterogeneous intensity. The type of enhancement of lesions was found similar after contrast medium administration.

Conclusions

In the presence of craniofacial FD during CT or MRI imaging of the head, a detailed description of FD lesions may provide an important clinical benefit by increasing radiological experience during the diagnostics of this rare disorder.

Diagnostic neuroimaging in neuro-ophthalmic disorders

PURPOSE OF REVIEW

Neuroimaging studies are a valuable diagnostic tool in the evaluation of a patient with neuro-ophthalmic disease. This review provides an approach to selecting an appropriate imaging study and interpreting the results.

RECENT FINDINGS

MRI and CT are the imaging studies most commonly employed in neuro-ophthalmology. Each modality has unique strengths that make it particularly suitable in certain clinical situations.

SUMMARY

In the current practice of neuro-ophthalmology, the clinician must be familiar with the uses and limitations of neuroimaging studies so they can be used appropriately to improve diagnostic accuracy.

Acromegaly and McCune-Albright syndrome

BACKGROUND

McCune-Albright syndrome (MAS) includes the triad of poly/monostotic fibrous dysplasia, café-au-lait spots, and hyperfunctioning endocrinopathies. Acromegaly affects around 20% of MAS patients.

AIMS

The objective was to review all reported cases of acromegaly associated with MAS.

METHODS

All studies and case reports of acromegaly in patients with MAS were systematically sought in the world literature up to January 2013. We also included new data (from three unreported cases) and updated data on 23 previously reported patients from our two centers.

RESULTS

We reviewed the cases of 112 patients (65 males). Mean age at diagnosis of acromegaly was 24.4 years (range, 3-64). Among the 40 pediatric patients, 23 (57%) had precocious puberty. GH/IGF-1 excess was suggested by accelerated growth in 85% of pediatric cases. Acromegaly was almost always associated with skull base fibrous dysplasia. Modern imaging techniques (computed tomography or magnetic resonance imaging) revealed an adenoma in 54% of the patients (macroadenoma in more than two-thirds). Median GH levels and mean IGF-1 SD score at diagnosis were 57 μg/L (2.8 to 291 μg/L) and 8 (2.3 to 24), respectively. Hyperprolactinemia was present in 81% (mean, 149 μg/L; range, 21-600). Pituitary surgery, performed in 25 cases, very rarely cured the GH/IGF-1 excess. Somatostatin analogs improved GH/IGF-1 levels in most patients but achieved control of acromegaly in only 17 (30%) of 56 patients. Pegvisomant achieved normal IGF-1 levels in 10 of 13 cases.

CONCLUSION

Acromegaly, which is present in 20-30% of patients with MAS, raises particular diagnostic and therapeutic issues.

Clinical, radiological, and pathological features of 26 intracranial and intraspinal malignant peripheral nerve sheath tumors

Object

Intracranial and intraspinal malignant peripheral nerve sheath tumors (MPNSTs) are rarely reported because of their extremely low incidence. Knowledge about these tumors is poor. In this study the authors aimed to analyze the incidence and clinical, radiological, and pathological features of intracranial and intraspinal MPNSTs.

Methods

Among 4000 cases of intracranial and intraspinal PNSTs surgically treated between 2004 and 2011 at Beijing Tiantan Hospital, cases of MPNST were chosen for analysis and were retrospectively reviewed. To determine which parameters were associated with longer progression-free survival (PFS) and overall survival (OS), statistical analysis was performed.

Results

Malignant PNSTs accounted for 0.65% of the entire series of intracranial and intraspinal PNSTs. Twenty-four (92.3%) of these 26 MPNSTs were primary. Radiologically, 26.9% (7 of 26) of the MPNSTs were misdiagnosed as nonschwannoma diseases. Twenty-one patients were followed up for 1.5 to 102 months after surgery. Twelve patients experienced tumor recurrence, and median PFS was 15.0 months. The 2- and 3-year PFS rates were 47.7% and 32.7%, respectively. Five patients died of tumor recurrence, and median OS was not available. The 2- and 3-year OS rates were 74.7% and 64.0%, respectively. Univariate analysis revealed that female sex, total tumor removal, and primary MPNSTs were significantly associated with a better prognosis. Multivariate analysis revealed that only total removal was an independent prognostic factor for both PFS and OS.

Conclusions

Malignant PNST within the skull or spinal canal is a rare neoplasm and is seldom caused by benign schwannomas. Radiologically, intracranial or intraspinal MPNST should be differentiated from meningioma, chordoma, fibrous dysplasia of bone, and ear cancer. Total resection whenever possible is necessary for the prolonged survival of patients, especially males.

Olfactory dysfunction as first presenting symptom of cranial fibrous dysplasia

Fibrous dysplasia (FD) is a benign bone disorder presenting with a variety of clinical manifestations. This is the first reported case of anosmia as presenting symptom of FD. We present the case of a 72-year-old female patient with a progressive olfactory dysfunction. Clinical examination revealed evidence of chronic rhinosinusitis; therefore the patient was treated with a course of oral corticosteroids. The patient had no improvement in her olfactory ability and imaging studies were ordered. Bony lesions characteristic of craniofacial FD were found, causing obstruction of the central olfactory pathway. This case emphasises the need to conduct further investigations in patients with rhinosinusitis and olfactory dysfunction especially when they present no response to oral steroid treatment.

False Positive FDG PET/CT Resulting from Fibrous Dysplasia of the Bone in the Work-Up of a Patient with Bladder Cancer: Case Report and Review of the Literature

Fibrous dysplasia of the bone (FDB) is a common, genetic, developmental disorder with a benign course. FDB can be seen anywhere throughout the skeleton. It is usually asymptomatic and found incidentally on imaging studies that are performed for other purposes. Although whole body 18 F-flourodeoxyglucose PET/CT (FDG PET/CT) is widely used in tumor imaging, infections and benign pathologies like FDB may cause false positive results. Herein we report the case of a 48-year-old FDB patient with transitional cell carcinoma of the urinary bladder. Restaging FDG PET/CT showed multiple mild to moderate hypermetabolic bone lesions which were initially misinterpreted as bone metastases. In this case report, we aimed to guide physicians in evaluating bone lesions in cancer patients with FDB in the light of the literature.

Thickened skull, scoliosis and other skeletal findings in Unverricht-Lundborg disease link cystatin B function to bone metabolism

PURPOSE

Unverricht-Lundborg disease (EPM1) is a rare type of inherited progressive myoclonic epilepsy resulting from mutations in the cystatin B gene, CSTB, which encodes a cysteine cathepsin inhibitor. Cystatin B, cathepsin K, and altered osteoclast bone resorption activity are interconnected in vitro. This study evaluated the skeletal characteristics of patients with EPM1.

METHODS

Sixty-six genetically verified EPM1 patients and 50 healthy controls underwent head MRI. Skull dimensions and regional calvarial thickness was measured perpendicular to each calvarial bone from T1-weighted 3-dimensional images using multiple planar reconstruction tools. All clinical X-ray files of EPM1 patients were collected and reviewed by an experienced radiologist. A total of 337 X-ray studies were analyzed, and non-traumatic structural anomalies, dysplasias and deformities were registered.

RESULTS

EPM1 patients exhibited significant thickening in all measured cranial bones compared to healthy controls. The mean skull thickness was 10.0±2.0mm in EPM1 patients and 7.6±1.2mm in healthy controls (p<0.001). The difference was evident in all age groups and was not explained by former phenytoin use. Observed abnormalities in other skeletal structures in EPM1 patients included thoracic scoliosis (35% of EPM1 patients) and lumbar spine scoliosis (35%), large paranasal sinuses (27%), accessory ossicles of the foot, and arachnodactyly (18%).

CONCLUSIONS

Skull thickening and an increased prevalence of abnormal findings in skeletal radiographs of patients with EPM1 suggest that this condition is connected to defective cystatin B function. These findings further emphasize the role of cystatin B in bone metabolism in humans.

The natural history of primary temporal bone myxoma

Primary myxomas of the temporal bone are rare tumors. If misdiagnosed, they can grow into locally aggressive expansile masses resulting in hearing loss, facial paralysis, dural invasion, and mass effect on the adjacent brain parenchyma. This case demonstrates the natural history of an extraordinarily rare tumor over a longer period not previously described. The importance of correlating histopathologic findings with diagnostic imaging features to enable an accurate diagnosis is also emphasized.

Craniofacial fibrous dysplasia

Despite recent advances in the understanding of the natural history and molecular abnormalities, many questions remain surrounding the progression and management of fibrous dysplasia (FD). In the absence of comorbidities, the expected behavior of craniofacial FD (CFD) is to be slow growing and without functional consequence. Understanding of the pathophysiologic mechanisms contributing to the various phenotypes of this condition, as well as the predictors of the different behaviors of FD lesions, must be improved. Long-term follow-up of patients with CFD is vital because spontaneous recovery is unlikely, and the course of disease can be unpredictable.

Craniofacial fibrous dysplasia (CFD) of the maxilla in an 11-year old boy: a case report

We present the case of a surgically treated 11-year old boy with a diagnosis of craniomaxillofacial fibrous dysplasia (CFD) in the maxillary sinus. When first seen in the outpatient clinic of our department he had minimal symptoms. After initial radiological diagnostics by computed tomography scans (CT-scans) the patient was treated operatively by radical excision of the tumor. The radiographs showed the typical intramedullary located and well-defined lesions, which eroded the cortical bone with the typical appearance of fibrous dysplasia. The histopathology showed the typical curved extending fibrous trabeculae in C, O and Y-shape which were embedded in a moderately cellular morphologically inconspicuous stroma, confirming the initial suspicion of fibrous dysplasia of the maxillary bone. Cone beam tomography was a valuable tool in determining the re-ossification of bone at the affected side. Local resection can be curative in limited disease.

Fibro-Osseous Lesions

This article describes the clinical, radiographic, gross, microscopic, and histologic features; differential diagnosis; molecular pathology; treatment; and prognosis of fibrous dysplasia, osteofibrous dysplasia, and adamantinoma of long bones.

The role of dual-phase Tc-99m MIBI in the evaluation of potentially operable lesions detected by bone scanning in fibrous dysplasia: a long-term prospective follow-up study

PURPOSE

The aim of this study was to determine the role of whole-body Tc-99m MDP bone scintigraphy (BSc) with dual-phase Tc-99m MIBI scintigraphy (DPMSc) in the assessment of fibrous dysplasia (FD) and the value of DPMSc in the detection of potentially operable lesions for guiding surgical treatment.

METHODS

Twelve patients with histopathologically confirmed FD were evaluated with BSc and DPMSc. The patients were clinically followed up for a mean duration of 75 months. BSc images have been used as a guide to identify the site and the extent of the skeletal involvement. The symptomatic lesions were evaluated with DPMSc.

RESULTS

Forty-three lesions were evaluated in 12 patients. BSc showed increased uptake in all of the lesions, whereas DPMSc findings correlated more accurately with the symptoms. Fifteen symptomatic lesions showed increased Tc-99m MIBI uptake on DPMSc, especially in the early phase of DPMSc. The sensitivity, specificity and accuracy values for the early phase in detecting the symptomatic lesions were 100 and 93%, and for delayed phase were 100 and 98%, respectively.

CONCLUSION

BSc is useful in determining the site and extent of the skeletal involvement, especially in polyostotic FD. It seems that the potentially operable symptomatic lesions may be evaluated more accurately with DPMSc as compared with BSc. In addition, it seems that DPMSc findings correlate with the symptoms of FD, and this relationship may have a role in improving the preoperative assessment for guiding surgical treatment. DPMSc could be useful in the work-up of symptomatic patients if our results are validated in a larger patient series.

Paranasal sinus and skull base fibro-osseous lesions: when is biopsy indicated for diagnosis?

BACKGROUND

Paranasal sinus fibro-osseous (FO) lesions represent a heterogeneous group, often sharing overlapping radiographic and pathologic features posing a dilemma in accurate diagnosis. The objective of this study was to correlate preoperative radiologic and postoperative histologic diagnosis to help guide a diagnostic algorithm.

METHODS

Retrospective analysis of 60 FO lesions between 1994 and 2010.

RESULTS

The mean age was 42.3 years with average follow-up of 12.5 months. The preliminary radiologic diagnosis was osteoma in 22 (36.7%), fibrous dysplasia (FD) in 9 (15%), ossifying fibroma (OF) vs FD in 5 (8.3%), and OF in 3 (5%) cases. The diagnosis was indeterminate in 21 (35%) cases. Management consisted of excision in 29 (48.3%), observation in 17 (28.3%), and biopsy in 14 (23.3%) patients. For patients undergoing resection or biopsy, positive predictive value of preoperative radiology was 100% (10/10) for osteoma, 85.7% (6/7) for FD, and 33.3% (1/3) for OF cases. For the indeterminate lesions, most common pathologic diagnoses for 21 patients included osteoma in 4 (17.4%), arrested pneumatization in 3 (14.3%), OF in 3 (14.3%), and FD in 2 (9.5%). For FD vs OF cases, 3 underwent surgery, revealing osteoma, FD, and OF in 1 patient each.

CONCLUSION

In this series, radiologic-histopathologic correlation was high for osteoma and FD and low for OF and OF vs FD. This data suggests that patients with classic radiologic characteristics of osteoma and FD may be observed, unless resection is warranted based on clinical symptomatology. Preoperative diagnosis of OF, OF vs FD, or indeterminate lesions may warrant a biopsy to establish firm diagnosis to guide definitive management, especially if preoperative computed tomography (CT) imaging is concerning for an aggressive FO neoplasm.

A case of craniofacial polyostotic fibrous dysplasia

We present the case of a patient with craniofacial polyostotic fibrous dysplasia. Polyostotic fibrous dysplasia is relatively rare and usually presents in late childhood/early adulthood. It is occasionally associated with endocrine disorders such as McCune-Albright syndrome. The benign pathology of this bone tumor belies its implications in the region of the skull base. Craniofacial polyostotic fibrous dysplasia can have devastating complications depending on which ostia are involved, including vision loss. Our patient was already beginning to experience visual field deficits from ischemic neuropathy. He was treated surgically with optic nerve decompression; however, the efficacy of this approach is currently being debated.