Surgical treatment of craniofacial fibrous dysplasia in adults

[Interdisciplinary Management of Orbital Diseases]

Diagnosis and therapy of orbital diseases is an interdisciplinary challenge, in which i.e. otorhinolaryngologists, ophthalmologists, radiologists, radiation therapists, maxillo-facial surgeons, endocrinologists, and pediatricians are involved. This review article describes frequent diseases which both, otolaryngologists and ophthalmologists are concerned with in interdisciplinary settings. In particular the inflammatory diseases of the orbit including orbital complications, autoimmunological diseases of the orbit including Grave´s orbitopathy, and primary and secondary tumors of the orbit are discussed. Beside describing the clinical characteristics and diagnostic steps the article focusses on the interdisciplinary therapy. The review is completed by the presentation of most important surgical approaches to the orbit, their indications and possible complications. The authors tried to highlight the relevant facts despite the shortness of the text.

Coexistence of meningioma and craniofacial fibrous dysplasia: a case series of clinicopathological study and literature review

BACKGROUND

The co-existence of meningioma and craniofacial fibrous dysplasia (CFD) is rare. Due to the similar radiological characteristics, it is challenging to differentiate such co-existence from solitary hyperostotic meningioma resulting in a dilemma of prompt diagnosis and appropriate intervention.

METHOD

We conducted a retrospective review of the data from 21 patients with concomitant meningioma and CFD who were treated at Beijing Tiantan Hospital from 2003 to 2021. We summarized their clinicopathological features and performed a comprehensive literature review. Additionally, we tested the characteristic pathogenic variants in exon 8 and 9 of GNAS gene and the expression of corresponding α-subunit of the stimulatory G protein (Gαs) related to CFD to explore the potential interactions between these two diseases.

RESULTS

The cohort comprised 4 men and 17 women (mean age, 45.14 years). CFD most commonly involved the sphenoid bone (n = 10) and meningiomas were predominantly located at the skull base (n = 12). Surgical treatment was performed in 4 CFD lesions and 14 meningiomas. Simpson grade I-II resection was achieved in 12 out of the 14 resected meningiomas and almost all of them were classified as WHO I grade (n = 13). The mean follow-up duration was 56.89 months and recurrence was noticed in 2 cases. Genetic study was conducted in 7 tumor specimens and immunohistochemistry was accomplished in 8 samples showing that though GNAS variant was not detected, Gαs protein were positively expressed in different degrees.

CONCLUSIONS

We presented an uncommon case series of co-diagnosed meningioma and CFD and provided a detailed description of its clinicopathological features, treatment strategy and prognosis. Although a definite causative relationship had not been established, possible genetic or environmental interplay between these two diseases could not be excluded. It was challenging to initiate prompt diagnosis and appropriate treatment for concomitant meningioma and CFD because of its similar radiological manifestations to meningioma with reactive hyperostosis. Personalized and multi-disciplinary management strategies should be adopted for the co-existence of meningioma and CFD.

Craniofacial fibrous dysplasia and aneurismal bone cyst in a patient with McCune-Albright syndrome. A case report and review of the literature

McCune-Albright syndrome (MAS) is a rare heterogeneous genetic disorder that is characterized by a triad of polyostotic fibrous dysplasia (FD), café au lait spots (CAL), and multiple hyperfunctional endocrinopathies. In general, it is diagnosed clinically. From the triads, 2 of the findings are enough to make the diagnosis. Craniofacial fibrous dysplasia is a term that is used to describe the fibrous dysplasia, which was localized at the craniofacial skeleton and is common in MAS patients. Aneurysmal bone cyst (ABC) is a rare non-neoplastic bone lesion that involves mostly the long bones and vertebrae and may occur very rarely in the craniofacial bones. ABCs may occur as secondary bony pathologies in association with various benign and malignant bone tumors and with fibrous dysplasia. Secondary ABC occurring in craniofacial FD is extremely rare. We present the case of a 21-year-old patient treated at our center for a right orbital aneurysmal bone cyst associated with MAS and provide a review of the relevant literature.

Polyostotic Fibrous Dysplasia: A Case Report of Rarity

A skeletal condition known as fibrous dysplasia (FD) is characterized by the replacement of healthy bone with fibrous bone tissue. One bone (monostotic) or several bones could be involved (polyostotic). Any bone in the body might become affected by FD. The skull and face bones are the most typical locations. It is connected to a GNAS1 gene mutation (20q13.2). It begins during childhood and could continue far into adolescence and adulthood. In this case study, a 22-year-old woman was identified as having polyostotic FD based on her clinical, radiological, and histological characteristics.

Augmented reality-assisted craniofacial reconstruction in skull base lesions - an innovative technique for single-step resection and cranioplasty in neurosurgery

Defects of the cranial vault often require cosmetic reconstruction with patient-specific implants, particularly in cases of craniofacial involvement. However, fabrication takes time and is expensive; therefore, efforts must be made to develop more rapidly available and more cost-effective alternatives. The current study investigated the feasibility of an augmented reality (AR)-assisted single-step procedure for repairing bony defects involving the facial skeleton and the skull base. In an experimental setting, nine neurosurgeons fabricated AR-assisted and conventionally shaped ("freehand") implants from polymethylmethacrylate (PMMA) on a skull model with a craniofacial bony defect. Deviations of the surface profile in comparison with the original model were quantified by means of volumetry, and the cosmetic results were evaluated using a multicomponent scoring system, each by two blinded neurosurgeons. Handling the AR equipment proved to be quite comfortable. The median volume deviating from the surface profile of the original model was low in the AR-assisted implants (6.40 cm³) and significantly reduced in comparison with the conventionally shaped implants (13.48 cm³). The cosmetic appearance of the AR-assisted implants was rated as very good (median 25.00 out of 30 points) and significantly improved in comparison with the conventionally shaped implants (median 14.75 out of 30 points). Our experiments showed outstanding results regarding the possibilities of AR-assisted procedures for single-step reconstruction of craniofacial defects. Although patient-specific implants still represent the gold standard in esthetic aspects, AR-assisted procedures hold high potential for an immediately and widely available, cost-effective alternative providing excellent cosmetic outcomes.

Cranial fibrous dysplasia: An institutional experience and review of the literature

Background:

Cranial or craniofacial fibrous dysplasia (CFD) is a rare entity which most often presents with either incidental finding or with pain/cosmetic disfigurement or visual/hearing problems. Multidisciplinary treatment with close follow-up or medical management/surgery is options. Management of these lesions can often give satisfying results. There is a dearth of neurosurgical literature on this subject matter. Our objective was to review the clinical symptomatology and outcome of CFD patients managed in our institution.

Methods:

This is a retrospective observational study of CFD patients managed in our institution over a period of 5 years. Clinical and radiological data were collected from departmental database. Outcomes were evaluated immediately and on 1–4 years follow-up.

Results:

A total of 21 patients were managed over a period of 5 years with age ranging from 12 to 55 years and symptoms of cosmetic issues or visual disturbance. Preoperative computed tomography scan with 3D reconstruction with bone window was done in all patients. In most of the patients (16/20), immediate reconstruction was done following excision. Five patients were managed conservatively. Follow-up was obtained over a period ranging from 1 to 4 years and all (except one) patients are doing well. Only one patient had permanent visual impairment in spite of early intervention.

Conclusion:

Craniofacial dysplasia has various modalities of management. Careful selection of patients for surgical or conservative management is feasible with good results both in short and long term.

Surgical Treatment of Fibrous dysplasia in the Maxillary Bone of a 12 Year-Old Girl: A Case Report

Fibrous dysplasia is a rare bony disorder with recurrent character distinguished by abnormal fibro-osseous tissue. One or more bones may be involved in this lesion; however, the maxilla is the most commonly affected bone in the maxillofacial region. Here, we present an interesting case of a surgically treated 12-year-old adult female patient with a diagnosis of craniofacial fibrous dysplasia (CFD) in the maxillary bone with an invasive expansion to the orbital bone who was referred to the Department of Oral and Maxillofacial, Mashhad Dental School, Mashhad, Iran, in Apr 2021. The patient was treated under general anesthesia by the surgical recontouring and bone shaving of the tumor. Several factors should be considered in choosing the best treatment such as pathological features of the lesion, patient's age, and risk of recurrence. However, surgical treatment, in this case, was beneficial to help the patient resuming a normal life. There is no published report describing bone recontouring and shaving management in an invasive case of craniomaxillofacial FD before the age of skeletal maturity due to the psychological effect of the deformity.

Calvarial lesions: overview of imaging features and neurosurgical management

Calvarial lesions are rare and can present as a variety of different diseases. The lesions can be palpable on the skin and cause local pain and paraesthesia and, depending on the location, neurological deficits can also occur. This research aims to present an overview of typical imaging features as well as neurosurgical management. We examined the charts of patients who underwent surgery on a calvarial lesion in our department between 2004 and 2017 (n=133). Retrospectively, the pre-, intra-, and postoperative data were analyzed with morphological and histological findings and compared with each other. Pain, swelling, cosmetically disturbing, and neurological deficits were the main complaints. Seventy-seven lesions were limited to the bone, while another 56 lesions showed an infiltrating growth in the adjacent tissue. Depending on the clinical signs and suspected diagnosis, a biopsy, a partial removal, or a complete resection was performed. Histiocytosis (n=20), meningiomas (n=20), metastases (n=19), and osteomas (n=16) were the most common lesions. Fibrous dysplasia (n=6) and intraosseous hemangioma (n=9) were less common; other lesions were present only in isolated cases. Imaging features may suggest the lesion to be benign or malignant, but the diagnosis can be only confirmed by histological examination. The surgical strategy depends on the complaints, location of the lesion, and suspected diagnosis. Adjuvant treatment should be initiated according to the histological findings.

Innovative Surgical Treatment of Severe Cherubism

Background:

Cherubism is an autosomal dominant syndrome characterized by excessive bilateral maxillomandibular bony degeneration and fibrous tissue hyperplasia. Conservative management is the preferred treatment as cherubism has a self-limiting course. Functional or emotional disturbances may, however, demand surgical intervention. We report a patient who underwent surgical intervention.

Method/Description:

He had significant enlargement of lower cheeks and bilateral lower lid scleral show. On computed tomography of the face, the patient had significant fibrous tissue involving bilateral maxilla and mandible. The mandibular tumor was excised. Given normal inferior border, bilateral sagittal split osteotomy was performed to infracture and inset the outer cortex. During the procedure, patient required blood transfusion intraoperatively, so the maxillary portion of the procedure was delayed until 6 months later. For the maxilla, bilateral transconjunctival approach was used to resect parts of the orbital floors that were concave, resulting in 1 × 2 cm defects bilaterally which were reconstructed using resorbable plates. Then the anterior maxillary tumor was excised.

Results:

The patient and his parents were satisfied with his appearance after surgery. The patient was noted to have improvement in contour and decreased scleral show. He has most recently followed up 15 months after the initial surgery. There were no long-term complications.

Conclusions:

Severity of cherubism influences the type of surgical intervention. The present case is innovative because this is the first reported case of recontouring orbital floors with resorbable plates and infracturing of the mandible using sagittal split osteotomies for surgical treatment of cherubism.

[Postoperative and posttherapeutic changes after primary bone tumors : What's important for radiologists?]

Posttreatment imaging of primary bone tumours represents a diagnostic challenge for radiologists. Depending on the primary bone tumour common radiological procedures, such as radiography, computed tomography (CT), and magnetic resonance imaging (MRI), are employed. Radiography and CT are particularly useful in benign bone tumours and in matrix-forming bone tumours. MRI comes into consideration with malignant tumour recurrence and tumoral soft tissue infiltration. Bone scintigraphy is of superior importance if a primarily multifocal manifestation of bone tumour or metastasizing tumour disease is suspected. Molecular imaging (FDG-PET and hybrid imaging, using CT) are gaining increasing importance in light of monitoring neoadjuvant chemotherapy and detecting recurrent tumour appearance. The current literature shows sensitivity and specificity values for recurrent detection of up to 92% and 93%. Diagnostic accuracy is as high as 95%, thus, exceeding accuracy values for CT (67%) and MRI (86%) by far. Likewise, this is also applicable for the assessment of the neoadjuvant chemotherapy. Moreover, PET-based modalities are able to establish prognostic statements using SUV-threshold values at baseline (especially for Ewing sarcomas). Advanced imaging techniques have made a great diagnostic step forward and have proven to be relevant and reproducible with respect to both relapse detection and treatment assessment. Furthermore, it is not clear whether a higher detection rate of early tumour recurrence will inevitably lead to better outcome and survival.

Odontogenic Sinusitis Caused by an Inflammation of a Dentigerous Cyst and Subsequent Finding of a Fibrous Dysplasia. A Case Report

We report the case of a 38-year old male patient with sinusitis caused by an infected follicular cyst due to an ectopic impacted third molar in the right maxillary sinus. A 10-day antibiotherapy regimen was administered; subsequently, the cyst and the third molar were removed achieving complete recovery. Fibrous dysplasia was diagnosed at follow-up examination (occupation of the maxillary sinus by bone tissue was observed in a radiographic examination) and confirmed by biopsy. In cases of odontogenic sinusitis, thorough examination is crucial, as evidenced by the case reported in this study. A Literature review was performed in order to identify the diagnostic methods currently available and the clinical features, complications and treatment for both, odontogenic maxillary sinusitis and fibrous dysplasia.

Fibrous dysplasia and cherubism

Fibrous dysplasia (FD) is a non-malignant fibro-osseous bony lesion in which the involved bone/bones gradually get converted into expanding cystic and fibrous tissue. The underlying defect in FD is post-natal mutation of GNAS1 gene, which leads to the proliferation and activation of undifferentiated mesenchymal cells arresting the bone development in woven phase and ultimately converting them into fibro-osseous cystic tissue. Cherubism is a hereditary form of fibrous dysplasia in which the causative factor is transmission of autosomal dominant SH3BP2 gene mutation. The disease may present in two distinct forms, a less severe and limited monostotic form, and a more aggressive and more widespread polyostotic form. Polyostotic form may be associated with various endocrine abnormalities, which require active management apart from the management of FD. Management of FD is not free from controversies. While total surgical excision of the involved area and reconstruction using newer micro-vascular technique is the only definitive treatment available from the curative point of view, but this can be only offered to monostotic and very few polyostotic lesions. In polyostotic varieties on many occasions these radical surgeries are very deforming in these slow growing lesions and so their indication is highly debated. The treatment of cranio-facial fibrous dysplasia should be highly individualized, depending on the fact that the clinical behavior of lesion is variable at various ages and in individual patients. A more conservative approach in the form of aesthetic recontouring of deformed bone, orthodontic occlusal correction, and watchful expectancy may be the more accepted form of treatment in young patients. Newer generation real-time imaging guidance during recontouring surgery adds to accuracy and safety of these procedures. Regular clinical and radiological follow up is required to watch for quiescence, regression or reactivation of the disease process. Patients must be warned and watched for any sign of nerve compression, especially visual impairment due to optic nerve compression. Rather than going for prophylactic optic canal decompression (which does more harm than good), optic nerve decompression should be done in symptomatic patients only, and preferably be done via minimal invasive endoscopic neuro-surgical approach than the conventional more morbid open craniotomy approach. There is growing research and possibilities that newer generation bisphosphonate medication may change the management scenario, as these medications show encouraging response in not only reducing the osteoclastic activity, but simultaneously also stimulating the osteoblastic and osteocytic activities. The explosion of genetic research and stem cell therapy may lead to better understanding and subsequently better treatment of FD in future.

Genetically induced abnormal cranial development in human trisomy 18 with holoprosencephaly: comparisons with the normal tempo of osteogenic-neural development

Craniofacial malformations are common congenital defects caused by failed midline inductive signals. These midline defects are associated with exposure of the fetus to exogenous teratogens and with inborn genetic errors such as those found in Down, Patau, Edwards' and Smith-Lemli-Opitz syndromes. Yet, there are no studies that analyze contributions of synchronous neurocranial and neural development in these disorders. Here we present the first in-depth analysis of malformations of the basicranium of a holoprosencephalic (HPE) trisomy 18 (T18; Edwards' syndrome) fetus with synophthalmic cyclopia and alobar HPE. With a combination of traditional gross dissection and state-of-the-art computed tomography, we demonstrate the deleterious effects of T18 caused by a translocation at 18p11.31. Bony features included a single developmentally unseparated frontal bone, and complete dual absence of the anterior cranial fossa and ethmoid bone. From a superior view with the calvarium plates removed, there was direct visual access to the orbital foramen and hard palate. Both the eyes and the pituitary gland, normally protected by bony structures, were exposed in the cranial cavity and in direct contact with the brain. The middle cranial fossa was shifted anteriorly, and foramina were either missing or displaced to an abnormal location due to the absence or misplacement of its respective cranial nerve (CN). When CN development was conserved in its induction and placement, the respective foramen developed in its normal location albeit with abnormal gross anatomical features, as seen in the facial nerve (CNVII) and the internal acoustic meatus. More anteriorly localized CNs and their foramina were absent or heavily disrupted compared with posterior ones. The severe malformations exhibited in the cranial fossae, orbital region, pituitary gland and sella turcica highlight the crucial involvement of transcription factors such as TGIF, which is located on chromosome 18 and contributes to neural patterning, in the proper development of neural and cranial structures. Our study of a T18 specimen emphasizes the intricate interplay between bone and brain development in midline craniofacial abnormalities in general.

Computer-Based Surgical Planning and Custom-Made Titanium Implants for Cranial Fibrous Dysplasia

BACKGROUND

The procedure of reconstruction after the removal of cranial fibrous dysplasia (FD) must be precise to achieve good functional and aesthetic results. Intraoperative modeling of implants is difficult and may cause cosmetic disturbances.

OBJECTIVE

To present our experience with the treatment of cranial FD using preoperative computer-based surgical planning of tumor removal with reconstruction of the cranium with custom-made titanium implants.

METHODS

Four patients underwent surgical treatment for cranial FD over a 2-year period. All patients were male with a mean age of 25.25 years and had monostotic-type FD. Computed tomography (CT) with 0.5-mm slices was obtained preoperatively. Computer-based planning of the tumor removal was performed, and a template was created by the computer to determine the margins of tumor removal. After this procedure, the preoperative computer-based construction of the titanium implant was performed. The patients underwent surgical treatment, and the tumor was removed with the use of this template. Then, the titanium implant was inserted onto the bone defect and fixed with mini-screws. Patients were followed up by periodic CT scans.

RESULTS

The histological diagnosis of all patients was FD. No intraoperative or postoperative complications have occurred. Postoperative CT scans showed complete tumor removal and confirmed appropriate cosmetic reconstruction. The mean follow-up period was 15.25 months.

CONCLUSION

Computer-based surgical planning associated with the production of custom-made titanium implants is a highly promising method for the treatment of cranial FD. Better radiological and cosmetic outcomes could be obtained by this technique with interdisciplinary work with medical designers.

Skull base embryology: a multidisciplinary review

INTRODUCTION

The skull base represents a central and complex bone structure of the skull and forms the floor of the cranial cavity on which the brain lies. Anatomical knowledge of this particular region is important for understanding several pathologic conditions as well as for planning surgical procedures. Embryology of the cranial base is of great interest due to its pronounced impact on the development of adjacent regions including the brain, neck, and craniofacial skeleton.

MATERIALS AND METHODS

Information from human and comparative anatomy, anthropology, embryology, surgery, and computed modelling was integrated to provide a perspective to interpret skull base formation and variability within the cranial functional and structural system.

RESULTS AND CONCLUSIONS

The skull base undergoes an elaborate sequence of development stages and represents a key player in skull, face and brain development. Furthering our holistic understanding of the embryology of the skull base promises to expand our knowledge and enhance our ability to treat associated anomalies.