BACKGROUND Monostotic fibrous dysplasia is a benign proliferation of fibrous and osseous tissues that expand medullary bone to cause symptoms due to compression of adjacent organs and anatomical structures. Focal seizures are rarely the first sign of this kind of lesion. This report describes a young female patient with left-sided focal motor seizures associated with fibrous dysplasia presenting as a mass in the right parietal bone. CASE REPORT An 18-year-old female student with left-sided focal motor seizures presented with a mass in the right parietal bone. Computed tomography revealed an expansile mixed-density lesion on the right parietal bone, a relatively homogeneous ground-glass appearance in the outer circumferential portion, and a lucent eccentric area with thinned but sclerotic borders. Magnetic resonance imaging revealed a homogeneously hypointense signal on T1WI, a small hyperintense signal on T2WI, and avid enhancement signal intensity on post-contrast T1. Electroencephalogram showed inter-ictal epileptiform activities derived from the right fronto-central lobe. Surgical en bloc resection with a margin of normal bone and cranioplasty were performed. Histopathology showed features indicative of fibrous dysplasia, including osteoid trabeculae arranged haphazardly in a dense fibroblastic stroma, irregular trabeculae lacking conspicuous osteoblastic rimming, and intervening fibrous stroma containing cytologically bland spindle cells. The patient achieved seizure control and has remained neurologically intact. CONCLUSIONS This report has highlighted the importance of early diagnosis of fibrous dysplasia of bone to exclude primary bone malignancy or bone metastasis, to ensure rapid management and symptom control.

Fibrous dysplasia (FD) is a rare skeletal disorder characterized by abnormal fibro-osseous connective tissue replacing normal bone. Despite its benign behavior, craniofacial FD can cause morphological disfigurement, headache, and even blindness as a result of the produced mass effect. Surgical resection is recommended when the patient shows apparent clinical symptoms or aggravating facial asymmetry. Postoperative complications have been reported, such as hematoma, surgical site infection, abscess formation, resorption of the bone graft used for reconstruction, and recurrence. An aneurysmal bone cyst (ABC) is a rare benign bony lesion that can occur secondary to preexisting bone tumor. Secondary ABCs in craniofacial FD are extremely rare in the literature, accounting for less than 30, all of which are either case reports or series. We report an extremely rare case of symptomatic secondary ABC arising from craniofacial FD that had been misdiagnosed with abscess formation or recurrence and was surgically removed. Notably, 17 years elapsed between the primary surgery and the complication of secondary ABC. The patient underwent total removal of secondary ABC. After surgery, symptoms were relieved, with no recurrence observed during a 6-month follow-up.

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.

OBJECTIVE. The purpose of this study was to explore the temporal changes in fibrous dysplasia (FD) at radiographic follow-up. MATERIALS AND METHODS. A total of 138 patients with FD who had undergone extremity radiography at least twice with a minimum 12-month interval between examinations were enrolled in this study. FD was monostotic in 99 patients and polyostotic in 39 patients. Patients were also classified according to skeletal maturity as follows: Patients 16 years old or younger were classified in the skeletally immature group (n = 34), and patients 17 years old or older were classified in the skeletally mature group (n = 104). We compared the initial and follow-up radiographs for the following findings: lesion size, opacity, sclerotic rim, calcification, and trabeculation. RESULTS. Of the 138 patients, radiographic follow-up showed no change in lesion size in 101 patients (73.2%), progression in 31 (22.5%), and regression in six (4.3%). FD in immature bones progressed more often than FD in mature bones (23/34 [67.6%] vs 8/104 [7.7%], respectively; p = 0.000), and polyostotic FD had a greater chance of regressing than monostotic FD (4/39 [10.3%] vs 2/99 [2.0%]; p = 0.032). A temporal change in FD lesion opacity was noticed in a minority of patients (19/138, 13.8%). Variable changes were observed in the sclerotic rim, calcification, and trabeculation. CONCLUSION. The radiographic follow-up of FD showed that approximately a quarter of lesions changed in size over time. Regardless of the change in lesion size, opacity and several morphologic features of FD changed during the follow-up period, which might reflect the histopathologic evolution of FD.

暂无摘要。

Monostotic fibrous dysplasia (MFD) of the lumbar spine represents an exceedingly rare lesion. A 26-year-old patient presented with a progressive osteolytic lesion of the vertebral body L2 and the diagnosis of MFD. A minimally invasive left-sided eXtreme Lateral Interbody Fusion (XLIF) approach with resection of the vertebral body L2 with placement of a mesh cage was performed. No complications were observed perioperatively and the symptoms rapidly improved. Minimally invasive piecemeal resection with a combined dorsolateral approach showed a favorable clinical and radiological outcome and seems to be a safe and reliable technique for MFD.

Monostotic fibrous dysplasia is a rare osteodystrophy that typically affects adolescents, manifests later in life, and may be associated with subclinical hormonal imbalances. It can lead to serious complications, including visual compromise. We report a case of presumed monostotic sphenoid fibrous dysplasia presenting with transient abducens nerve palsy and esotropia in an otherwise healthy infant. The mechanism of transient, noncompressive abducens nerve palsy is not clearly understood but has been theorized to be secondary to localized inflammation during a cycle of florid bone remodeling that includes cyst formation, microhemorrhage, and resorption.

BACKGROUND: Monostotic fibrous dysplasia (MFD) involving the spine is rare, and the treatment options are controversial. Surgery is needed when patients suffer from persistent pain, spinal cord compression/injury, and vertebral collapse/instability. Treatment methods include biopsy/observation, corpectomy with instrumented fusion, posterior fusion, vertebroplasty (VP), curettage and bone graft, and complete removal of the vertebra with a combined anterior and posterior fusion procedure.
METHODS: The patient was a 56-year-old woman with a 2-year history of neck pain. No obvious abnormalities were detected on neurological or physical examination, and laboratory findings were all within normal limits. An imaging examination suggested a C7 vertebral bone tumor. The patient refused to continue conservative observation treatment and requested surgery. Open VP of the C7 vertebral body was carried out, and her postoperative neck pain was completely relieved. The postoperative pathological results supported the diagnosis of fibrous dysplasia, and the patient was ultimately diagnosed with MFD. At the 12-month follow-up visit, the patient reported no clinical symptoms, and no signs of tumor recurrence were detected.
CONCLUSIONS: VP can relieve pain while stabilizing the spine. Thus, the surgical treatment of MFD vertebral lesions by VP is a valuable option.

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.

Fibrous dysplasia (FD) is generally considered to be a benign disease that affects the bones, but it has potential to become malignant over time, generally several decades after its initial diagnosis. Radiation therapy can induce malignant transformation of FD; however, reports have indicated a few cases of malignant transformation of FD in the absence of radiation therapy. Angiosarcoma is a particularly rare type of cancer in the oral region, which accounts for less than 1% of all soft-tissue sarcomas. Herein, we reported a case of a 62-year-old man with monostotic FD of the left maxilla of over 50 years\' duration that underwent malignant transformation into an epithelioid-type angiosarcoma. To the best of our knowledge, this is the first report of such case.