Fibrous Dysplasia of Skull

Fibrous dysplasia of the head and neck in Southern Finland: a retrospective study on clinical characteristics, diagnostics, and treatment

PURPOSE

Fibrous dysplasia (FD) is a rare genetic disease with benign bone tumors. FD can affect one (monostotic FD) or multiple bones (polyostotic FD), with craniofacial lesions being common. Because of its rarity, there are only few clinical reports on FD in the head and neck region and its clinical characteristics remain incompletely defined. This study aimed to determine patient demographics, symptoms, diagnostics, and given treatment in patients with FD of the head and neck in a Finnish population.

METHODS

A retrospective review on all patients diagnosed with or treated for FD of the head and neck at the Helsinki University Hospital during 2005-2020.

RESULTS

In total 74 patients were identified; 54% were male and the mean age 45 years. Overall 95% had monostotic FD. Mandibula and maxilla were the most common anatomic sites. Majority of patients had symptoms, most commonly pain and lesion growth, and 49% had extra-skeletal symptoms. For all, diagnosis was primarily based on imaging findings, biopsies were obtained from 41%. Altogether 54 patients (73%) were managed by observation only, 20 patients (27%) received treatment; ten bisphosphonates, six surgery and four both.

CONCLUSION

Although highly variable in its clinical manifestations, head and neck FD lesions are often symptomatic and impose risk for extra-skeletal complications. Treatment is often conservative but should be individually tailored. Future studies are encouraged to better define the disease characteristics and hopefully offer new treatment possibilities.

Craniofacial fibrous dysplasia: Systematic review of facial management

Craniofacial fibrous dysplasia (CFD) may be associated with major cosmetic or functional consequences. However, management recommendations for CFD are currently unavailable. Therefore, this systematic literature review aimed to review the existing approaches for CFD management and propose a management algorithm. The focus question was "What are the different options for CFD treatment and their complication rates?" The MEDLINE database was searched, and 33 articles evaluating a total of 1154 patients were reviewed. The bias assessment showed that 20 of the 33 studies had a high or intermediate risk of bias, mainly because of retrospective data collection and small patient numbers. Radical surgery showed a lower recurrence rate than debulking, but its use should be weighed against the morbidity caused by the reconstruction performed in this technique. Orbital decompression using a radical technique or debulking is effective in cases showing exophthalmos or dystopia. Surveillance is a viable option for asymptomatic and/or non-progressive lesions. In cases showing optic nerve compression, prophylactic decompression should be avoided, and decompression should be performed only when patients show diminished visual acuity or visual field defect. Although bisphosphonates have shown efficacy in pain management, their posology requires further discussion. A management algorithm is presented.

Management Strategies of Fibrous Dysplasia Involving the Paranasal Sinus and the Adjacent Skull Base

OBJECTIVE

Current management of fibrous dysplasia (FD) involving the paranasal sinuses and the adjacent skull base is currently controversial. This study aims to present our experience in the management strategy of FD that involves the paranasal sinuses and the adjacent skull base.

METHODS

Twenty three patients from 2006 to 2019 with monostotic fibrous dysplasia (MFD), polyostotic fibrous dysplasia (PFD), or McCune-Albright syndrome (MAS) involving the paranasal sinuses and the adjacent skull base were retrospectively reviewed. This study series was divided into 3 groups based on management strategies: the observation group, the surgery group, and the optic nerve decompression group.

RESULTS

The observation group included 9 patients with asymptomatic MFD with stable condition during the follow-up period of 15 to 164 months. The surgery group included 10 symptomatic patients with MFD who had personalized endoscopic endonasal surgery. The symptoms of the patients were relieved after surgery. The optic nerve decompression group included 4 patients with visual loss, who underwent endonasal endoscopic optic nerve decompression (EOND) with the aid of image-guided navigation. Their vision improved after surgery.

CONCLUSIONS

Clinical observation and periodic computed tomography (CT) scan are adopted for asymptomatic patients. Surgery is indicated in symptomatic patients. Optic nerve decompression is recommended as soon as possible if the patient has visual loss, whereas prophylactic decompression is not recommended if the optic nerve is encroached by FD without visual loss. Navigation plays an important role in endoscopic surgery involving the paranasal sinuses and the adjacent skull base, especially in FD resection and optic nerve decompression.

Management and surgical approach ingenuity for nasal fibro-osseous lesions at our facility: A case series of 15 patients

To retrospectively evaluate our treatment algorithm and surgical approaches for nasal fibro-osseous lesions at our hospital. Fifteen patients with nasal fibro-osseous lesions treated from January 1, 2010, to January 31, 2020 were included. Among them, 13 patients who underwent surgery were divided into groups A and B, based on whether they were treated before or after the treatment algorithm was established. The extent of the lesion, surgical approach, and outcomes, including bone regrowth assessed postoperatively using computed tomography at 6 months, were analyzed. In group A, six cases were treated via endoscopy and two via a combined endoscopy and external approach. In group B, three cases were treated via endoscopy, one via combined endoscopy and external approach, and one combined with craniotomy. Two group A cases and no group B cases had residual lesions postoperatively. Postoperative bone regrowth occurred in three group A patients and no group B patients. Multi-angled approaches for nasal fibro-osseous lesions based on the unified treatment algorithms used in the study may lead to a reduction in postoperative recurrence and complication rates.

Extensive titanium mesh invasive cranial fibrous dysplasia

Background:

Craniofacial fibrous dysplasia (FD) is a benign lesion. It presents as bony swelling. Even after complete excision, it has a tendency to recur due to some residual lesion in normal bone. Recurrence at same site is common, but it recurs in bone. We are reporting a rare case of recurrent FD engulfing titanium mesh.

Case Description:

A 22-year-old girl, who underwent frontal FD excision and reconstruction using titanium mesh surgery 2 years back, came with complaint of progressive bony swelling at same site for 1 year. CT head confirmed bony lesion involving mesh, frontal air sinus. She underwent complete excision of lesion and cranioplasty using bony cement. Biopsy confirmed recurrence of FD and invasion of titanium mesh.

Conclusion:

Recurrence of FD, involving cranioplasty titanium mesh, is extremely rare. It suggests local invasiveness of lesion. Recurrence can be prevented by excision of lesion with free bony margins.

The Role of Staged Cryosurgery and Three-Dimensional Computed Tomography Integrated Navigation System in the Surgical Management of Severe Involvement of Craniofacial Polyostotic Fibrous Dysplasia

Fibrous dysplasia (FD) is a developmental bone disorder caused by the hamartamatous proliferation of bone-forming cells. A 29-year-old male patient with diagnosis of FD was admitted to our clinic with the symptoms of severe craniomaxillofacial involvement of FD beginning from last year. Neurological examination revealed diplopia, horizontal nystagmus, conductive hearing loss, and partial vision loss. In his medical history, it was reported that he had undergone intramedullary nailing operation in his left femur due to a pathological fracture approximately 8 years ago in the orthopedics clinic of our institution. The patient underwent 3 consecutive surgeries by our plastic and neurosurgical team. The patient was followed-up in the neuro-intensive care unit between the surgical sessions and 1 week after the last operation. Afterwards, he was transferred to the neurosurgical department. No postoperative complication was detected. The preoperative signs were recovered. During his 6th month follow-up control-visit, all his preoperative symptoms were improved. In addition, the patient was satisfied with his postoperative cosmetic improvement. In conclusion, virtual surgical planning and intraoperative surgical navigation systems can make the challenging cases possible to operate with increasing the safety margin of the surgical procedures for polyostotic FD.

Midfacial degloving approach for management of the maxillary fibrous dysplasia: a case report

Background

Fibrous dysplasia (FD) is a benign bone lesion characterized by the progressive replacement of normal bone with fibro-osseous connective tissue. The maxilla is the most commonly affected area of facial bone, resulting in facial asymmetry and functional disorders. Surgery is an effective management option and involves removing the diseased bone via an intraoral approach: conservative bone shaving or radical excision and reconstruction.

Case presentation

This case report describes a monostotic fibrous dysplasia in which the patient’s right midface had a prominent appearance. The asymmetric maxillary area was surgically recontoured via the midfacial degloving approach under general anesthesia. Follow-up photography and radiographic imaging after surgery showed the structures were in a stable state without recurrence of the FD lesion. Furthermore, there were no visible scars or functional disability, and the patient reported no postoperative discomfort.

Conclusions

In conclusion, the midfacial degloving approach for treatment of maxillary fibrous dysplasia is a reliable and successful treatment option. Without visible scars and virtually free of postoperative functional disability, this approach offers good exposure of the middle third of the face for treatment of maxillary fibrous dysplasia with excellent cosmetic outcomes.

Strategies for the Optimal Individualized Surgical Management of Craniofacial Fibrous Dysplasia

BACKGROUND

The surgical management of craniofacial fibrous dysplasia is controversial. The purpose of this study was to report the surgical outcomes of individualized management of craniofacial fibrous dysplasia of a single institution.

METHODS

Data from patients (n = 20) with craniofacial fibrous dysplasia, who were surgically treated between 2007 and 2014, were analyzed. Surgical approach (radical or conservative surgery) was individualized according to age, craniofacial anatomical site (zones I to IV of Chen and Noordhoff), functional issues, aesthetic impairment, patients/parents' preferences, and surgical team experience. The surgical outcomes (radical surgery group versus conservative surgery group) were compared based on the age at the time of the procedure, the length of hospital stay, reoperation, recurrence and complication rates, and the Whitaker grading system.

RESULTS

Significant (all P < 0.05) differences were observed in patients with craniofacial fibrous dysplasia who were treated with radical excision (65%) compared with those treated with limited reduction burring (35%), according to age (19.22 years versus 12.57 years), the length of hospital stay (3.56 days versus 1.29 days), recurrence (15% versus 71%), and number of subsequent procedures (1 intervention versus 2.4 interventions), respectively. The radical surgery group presented a significantly (P < 0.05) lower initial Whitaker outcome score than the conservative surgery group (1.89 and 2.57, respectively). Similar (all P > 0.05) final Whitaker outcome scores (1.56 versus 1.71) and surgical complication rates (11% versus 14%) were recorded between the treatment groups.

CONCLUSIONS

Based on clinical experience and surgical outcomes presented in this study, the surgical approach of craniofacial fibrous dysplasia should be tailored to individual patient's needs.

Post-traumatic fibrous dysplasia of the parietal bone: A rare entity

Fibrous dysplasia (FD) is a rare fibro-osseous lesion in which normal bone is replaced by abnormal fibrous tissue. Although a congenital disorder, a single case report of traumatic etiology had been described in the literature. We report a case of monostotic FD of the parietal calvarium in a 21-year-old female patient who presented to us with a single swelling in the parietal region been noticed after head injury sustained at the age of 7 years. After imaging investigations, the lesion was excised via craniotomy followed by cranioplasty in the same sitting. The histopathological evidence was suggestive of FD. To the best of our knowledge, this is the second case of a posttraumatic cranial FD and the first case describing the growing mass in the parietal bone secondary to head injury.

Surgical Management of Polyostotic Craniofacial Fibrous Dysplasia: Long-Term Outcomes and Predictors for Postoperative Regrowth

BACKGROUND

The mainstay of treatment for craniofacial fibrous dysplasia is surgical; however, optimal indications and techniques are poorly understood, particularly in polyostotic disease and McCune-Albright syndrome. This study investigated surgical indications and risk factors for recurrence in a large cohort.

METHODS

One hundred thirty-three craniofacial fibrous dysplasia subjects in a natural history study were evaluated. Radiographic studies, operative reports, and clinical records were reviewed.

RESULTS

Thirty-six subjects underwent 103 craniofacial procedures (mean, 2.8 operations per subject), with 13.5 ± 10.5-year follow-up (range, 0 to 39 years). The most common indication was craniofacial deformity (n = 61 operations), including 36 initial operations (59 percent) and 26 reoperations (41 percent). Mean time to reoperation was 3.4 ± 3.2 years (range, 0.3 to 13.3 years). Regrowth occurred after 42 operations (68 percent), and was more frequent after operations in subjects with McCune-Albright syndrome growth hormone excess [22 of 25 operations (88 percent)] than without growth hormone excess [15 of 36 operations (58 percent); p = 0.02]. Of 11 subjects with growth hormone excess, nine (82 percent) were undiagnosed at the time of their initial operation. Regrowth was more frequent after debulking procedures [31 of 38 (82 percent)] than after more aggressive reconstructions [nine of 20 (45 percent); p = 0.007]. Eleven subjects underwent treatment for aneurysmal bone cysts, with recurrence in one subject. Eleven subjects underwent biopsies and none had complications or regrowth.

CONCLUSIONS

Craniofacial fibrous dysplasia regrowth and reoperation are common, particularly after debulking procedures. Outcomes are favorable for aneurysmal bone cysts and biopsies. McCune-Albright syndrome growth hormone excess is a risk factor for regrowth, and may be underdiagnosed in surgical patients. Surgeons should be aware of appropriate screening for endocrinopathies in fibrous dysplasia. These findings highlight the importance of a multidisciplinary approach to craniofacial fibrous dysplasia, and individualized care with long-term follow-up.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

[Endoscopic transnasal surgery for giant fibrous dysplasia of the skull base, spreading to the right orbital cavity and nasopharynx (a case report and literature review)]

BACKGROUND

An extended endoscopic endonasal approach is increasingly used in surgical treatment of space-occupying skull base lesions. The international literature reports only 20 cases of surgical treatment for fibrous dysplasia (PD) of the skull base using the endoscopic endonasal approach. We present our experience with the endoscopic endonasal approach in surgical treatment for giant fibrous dysplasia of the skull base, spreading to the right orbital cavity and nasopharynx.

CLINICAL CASE

A 26-year-old male patient presented with cranial pain, Vth nerve dysfunction on the right, right keratopathy. OD=0.2 (near acuity - 0.3), OS=1.0, OD - incomplete eyelid closure of 2 mm, conjunctival injection, mucous discharge, corneal opacity in the lower pole and paracentrally, OS - normal appearance. Severe right-sided exophthalmos (more than 15 mm), impaired nasal breathing on the right, nasal (hemorrhagic) discharge. Magnetic resonance imaging and spiral computed tomography scans revealed a bone density lesion located in the area of the orbit, nasal cavity, maxillary sinus on the right, and labyrinth of the ethmoid bone. The patient underwent endonasal endoscopic resection of the lesion.

RESULTS

The lesion was resected totally, which was confirmed by control SCT. Right-sided exophthalmos partially regressed (on the right: exophthalmos of 8 mm; protrusion: OD=23 mm, OS=15 mm; the eyeball was displaced downward and outward). The visual and oculomotor functions did not change. The neurological status remained at the preoperative level.

CONCLUSION

Fibrous dysplasia of the skull base is an extremely rare disease. Modern techniques expand the indications for surgery of giant tumors of the skull base using minimally invasive approaches, in particular the endoscopic endonasal approach.

Multiportal Combined Transorbital and Transnasal Endoscopic Resection of Fibrous Dysplasia

Introduction Historically, access to the anterior skull base was achieved with open procedures. The paradigms to this approach were challenged with the advent of minimally disruptive endoscopic surgical techniques and supporting technology. The next step in the evolution of minimally disruptive surgery was the combination of multiportal endoscopic surgery. Results The patient was an 18-year-old man who presented with right-sided proptosis. Further diagnostic tests revealed a fibrous dysplasia (FD) occupying the skull base and orbit. The lesion was successfully resected. Conclusions The location of the tumor in this case was challenging, in which surgeons at some centers would have opted to have performed as an open procedure instead of endoscopically. The combined transnasal/transorbital approach is an uncommonly used technique that we have used to remove this tumor successfully. The patient also had a unique disease (FD) in a unique location that was treated without complications. This case report highlights how surgeons may use an expanded armamentarium in dealing with complex pathologies.

Recurring craniofacial fibrous dysplasia with extensive titanium mesh invasion

The recurrence and regrowth of craniofacial fibrous dysplasia (FD) along the repaired titanium mesh (TM) after total removal are extremely rare. A 22-year-old man was admitted to our hospital complaining of progressive proptosis and sudden vision loss of the right eye. Craniofacial FD was histologically diagnosed 3 years ago, and the involved frontal bone was totally removed and reconstructed with TM in his first surgery. Based on previous medical history, radiographic features, and clinical findings, the recurrence was considered, and the patient underwent surgical treatment. He had an uneventful postoperative course, and during the follow-up, his proptosis was gradually relieved, and the visual acuity also improved. In this article, we present the regrowth of craniofacial FD into TM and describe the clinical features, mechanism, and treatment of this condition.

Solitary lesions of the clivus: what else besides chordomas? An extensive clinical outlook on rare pathologies

BACKGROUND

Solitary non-chordomatous lesions of the clivus are rare pathologies, which represent a diagnostic challenge. This study provides an overview of the clinical, radiological and prognostic characteristics of non-chordomatous clival lesions, highlighting current therapeutic options.

METHODS

Twenty-two non-chordomatous lesions of the clivus were collected. A retrospective analysis of clinical and radiological patterns as well as survival data was conducted.

RESULTS

Clinical presentation was a result of local mass effect. Imaging features, although mainly specific, were not always diagnostic. Extent of surgery was gross total in 45.5 % of cases. Depending on the histology, biological behaviour and presence of seeding, adjuvant treatment was performed, tailoring the treatment strategy to the single patient.

CONCLUSIONS

Solitary non-chordomatous lesions of the clival bone are more prevalent than expected. They should be approached with a correct differential diagnosis, considering specific epidemiological, radiological, and histopathological characteristics, to minimise diagnostic bias and allow the planning of the best treatment strategy.

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.

Fibro-osseous lesion of the cranium in an adolescent patient

Background:

Fibrous dysplasia, ossifying fibroma, and desmoplastic fibroma are rare benign calvarial lesions, which can have local aggressive behavior. These tumors can present with similar clinical and radiologic characteristics making diagnosis difficult at times.

Case Description:

A 16-year-old male presents after noting an indentation of his skull. Comparison with current and previous imaging revealed progressive erosion of the skull underlying the indentation.

Conclusion:

Fibrous dysplasia, ossifying fibroma, and desmoplastic fibroma are rare fibro-osseous tumors with similar characteristics radiographically. Accurate diagnosis of these tumors can be difficult even with the combination of clinical presentation, imaging, and pathology. The treatment of choice is resection and cranial reconstruction, if necessary, with close follow-up as recurrence can occur.

Clinical characteristics of craniomaxillofacial fibrous dysplasia

BACKGROUND

The clinical characteristics of craniomaxillofacial fibrous dysplasia (FD) have not been clearly identified. The objective of this meta-analysis is to assess the predominance of the monostotic form of FD using an evidence-based review. Furthermore, we examined the laterality and sex dominance of FD in patients from international study populations.

METHODS

We performed a systematic search of PubMed, Embase, Cochrane Central Register of Systematic Reviews, Cochrane Central Register of Controlled Trials and EBSCO for trials published through August 2013. Data extracted from the literature were analysed with Review manager 5.0.24.

RESULTS

The results of this study showed that unilateral FD occurred more frequently than bilateral FD (RR, 12.37; 95% CI, 2.92-61.24; P = 0.008, N = 263 patients). For unilateral FD, there was no significant difference between cases involving the left or right side of the face (RR, 0.98; 95% CI, 0.66-1.44; P = 0.91; N = 201 patients). There were no significant sex-dependent differences for monostotic and polyostotic forms of craniomaxillofacial FD.

CONCLUSION

There is a significantly higher percentage of the unilateral form than the bilateral form in the craniomaxillofacial FD studies analysed, and an almost equal distribution of left- and right-sided unilateral FD. These proportions were maintained among males and females and there were nearly equal frequencies of monostotic and polyostotic FD.

Surgical treatment of craniofacial fibrous dysplasia in adults

Craniofacial fibrous dysplasia (FD) is a rare disorder that may require neurosurgical expertise for definitive management; however, surgical management of FD in adult patients is uncommon. Although other therapies have been shown to slow progression, the only definitive cure for adult craniofacial FD is complete resection with subsequent reconstruction. The authors review the biological, epidemiologic, clinical, genetic, and radiographic characteristics of adult FD, with an emphasis on surgical management of FD. They present a small series of three adult patients with complex FD that highlights the surgical complexity required in some adult patients with FD. Because of the complex nature of these adult polyostotic craniofacial cases, the authors used neurosurgical techniques specific to the different surgical indications, including a transsphenoidal approach for resection of sphenoidal sinus FD, a transmaxillary approach to decompress the maxillary branch of the trigeminal nerve with widening of the foramen rotundum, and complete calvarial craniectomy with cranioplasty reconstruction. These cases exemplify the diverse range of skull base techniques required in the spectrum of surgical management of adult FD and demonstrate that novel variations on standard neurosurgical approaches to the skull base can provide successful outcomes with minimal complications in adults with complex craniofacial FD.

Paediatric craniofacial fibrous dysplasia: the Hospital for Sick Children experience and treatment philosophy

Craniofacial fibrous dysplasia is a benign developmental anomaly in which normal bone is replaced by fibro-osseous tissue. The aim of this study was to audit the patient population at a tertiary paediatric centre and report our treatment protocols. A retrospective chart review of all patients with craniofacial fibrous dysplasia treated at the Hospital for Sick Children between 1999 and 2010 was performed. The treatment algorithm used by our centre is presented. A total of 55 patient records were reviewed; 37 patients had sufficient documentation for study; 27 (16 male, 11 female) patients underwent surgery at our institution, of these patients, 26 had post-operative follow up of greater than one year (mean 41 months; median 24 months). Mean age at presentation was 9.9 years (median 10 years) and mean age of surgery was 13 years. Ten patients underwent surgery on the fronto-orbital region, 7 of the calvarium, 2 the skull base and 8 upon tooth-bearing bones. Fourteen cases underwent debulking surgery as their primary therapy whereas 13 patients had complete resection. Nine patients experienced recurrence and all but one case of these occurred in patients that underwent debulking therapy. When age of surgery is considered, total resection and reconstruction or debulking surgery after skeletal maturity has a lower recurrence rate (1/7 cases) than earlier surgery (8/16). Complete resection at any age and debulking surgery once skeletal maturity has been reached may be associated with lower recurrence rates than incomplete resections at an earlier age. Patients with McCune-Albright syndrome may benefit from repeated debulking procedures rather than complex resections and reconstructions.

Benign hyperostotic mass of the frontal bone

Diagnosis of a slow-growing mass of the cranium can be challenging. We present a rare clinical report of a 19-year-old woman with a unilateral mass of the frontal bone. Pathological diagnosis was hyperostosis, which is extremely rare in this age group. A comprehensive review of literature with recommendations for diagnostic modalities and treatment options is reported. Specifically, hyperostosis frontalis interna can be evaluated with computed tomography imaging of the cranium and treated with resection and reconstruction with split calvarial bone grafts. Annual radiographic imaging is recommended to ensure remission.

Fibrous dysplasia of the clivus

Fibrous dysplasia (FD) of craniofacial structures is well documented, however, its involvement of the clivus is seldom described. We report a case of clival FD in a young man who presented with headache localized to the occipital area. The radiological studies revealed a monostotic disease confined to the clivus, with typical findings of hypointensity on magnetic resonance images and ground-glass density on computed tomography. The diagnosis of FD was confirmed on pathological examination of specimens taken through transsphenoidal surgery. The patient showed reduction of symptoms and no change of residual lesion on follow-up imaging taken 2.5 years later after surgery. This study includes clinical aspect, radiographic appearance, differential diagnosis and treatment strategy of this rare skull base lesion.