Osteoblastoma arising from the ethmoidal sinus

Osteoblastoma of the frontal sinus: A rare case presenting with seizures and pneumocephalus

Key Clinical Message

Osteoblastoma of the frontal sinus, although rare, can manifest with seizures and pneumocephalus, underscoring the importance of thorough evaluation and complete surgical excision to prevent serious complications and ensure optimal patient outcomes.

Abstract

Osteoblastoma is an infrequent bone tumor, with origins typically in the vertebrae and long bones. While craniofacial involvement is rare, it may occur in regions such as the paranasal sinuses. We present a case of osteoblastoma located in the frontal sinus, an exceptionally uncommon site, resulting in seizures secondary to pneumocephalus. A 21-year-old male presented with a generalized tonic-clonic seizure and postictal confusion. Imaging studies revealed a well-defined lesion in the left frontal sinus causing cortical breach, destruction of the posterior wall, and pneumocephalus. A total surgical excision was performed through bifrontal craniotomy. Histopathological analysis confirmed the diagnosis of osteoblastoma. Postoperative recovery was uneventful, with a follow-up CT scan showing complete lesion excision. Osteoblastomas, especially in the cranial sinuses, are rare entities that may present asymptomatically but can lead to severe complications. The risk of recurrence underscores the importance of complete surgical resection for optimal patient outcomes.

Eccentric, mature osseous cap: A distinct imaging feature of sinonasal osteoblastoma

BACKGROUND

With the exception of osteomas, bone neoplasms that originate in the sinonasal cavity are seldom diagnosed on preoperative imaging due to a lack of characteristic radiographic features. Here we described the unusual occurrence of an osteoblastoma in the paranasal sinuses, and we drew focus to its salient imaging features. A highly unique imaging sign was indicated, and its pathologic basis was explained, with concurrent review of the literature.

METHODS

Case series and review of the literature.

RESULTS

Two cases of sinonasal osteoblastoma were managed by definitive surgical resection. Both tumors on preoperative computed tomography demonstrated an expansile, heterogeneous fibro-osseous lesion with an eccentric, mature osseous cap. The dense osseous cap seen on imaging corresponded to a rim of mature bone on histopathology. A review of existing literature revealed the presence of this imaging sign in all reported cases.

CONCLUSION

Sinonasal osteoblastoma is an extremely rare entity with undefined imaging characteristics to guide preoperative decision-making. Here we reported, to our knowledge, the first description of a characteristic imaging sign of an eccentric, mature osseous cap, which corresponded histologically to a single peripheral layer rim of osteoblasts, a unique trait of osteoblastoma.

Clinical features and surgical management of spinal osteoblastoma: a retrospective study in 18 cases

OBJECTIVES

To investigate the clinical manifestation and surgical outcome of spinal osteoblastoma.

METHODS

From June 2006 to July 2011, 18 patients with spinal osteoblastoma treated surgically were analyzed retrospectively. There were 11 males and 7 females with an average age of 27.5 years（range, 16-38 years). The tumors were located at C5 in 7, C6 in 6, C7 in 3, C6-T1 1 in 1 and T11 in 1. Based on WBB classification, 16 were 1-3 or 10-12 and 2 were 4-9 and 1-3. 18 operations had been performed with en bloc resection. A posterior approach was used for 16 patients, and a combined posterior and anterior approach was used for 2 patients. Reconstruction using instrumentation and fusion was performed using spinal instrumentation in 13 patients. We used visual analogue scales (VAS) to evaluate the change of pain before and after the operation, and the McCormick System to assess functional status of the spine. Imaging test was used to review the stability and recurrence rate of spine cord, and the confluence of graft bones.

RESULTS

All cases were followed up for 24-80 months (average, 38.4 months). The average surgical time was 120.8 minutes (range, 80-220 minutes), with the average intraoperative blood loss of 520 ml (range, 300-1200 ml). During the follow-up period, the VAS grade reduced from 6.46±1.32 to 2.26±1.05 (P <0.05). 15 patients had neurological function improved and 3 remained no change which was evaluated by McCormick scale for spinal function status at final follow-up.

CONCLUSIONS

Spinal osteoblastoma has its own specific radiographic features. There is some recurrence in simple curettage of tumor lesion. The thoroughly en bloc resection of tumor or spondylectomy, bone fusion and strong in Ter fixation are the key points for successful surgical treatment.

Benign osteoblastoma of the ethmoid sinus

Osteoblastoma is categorized as a benign bone-forming tumor, which occurs rarely in the craniofacial region. We report a case of osteoblastoma developed in the nasal cavity and ethmoid sinus in a 14-year-old girl whose chief symptom was nasal obstruction and exophthalmos on the right side. CT revealed the lesion having the same density as bone and a ground-glass border, expanding to the nasal and paranasal cavities. Complete removal was accomplished under endoscopic view, although the tumor was removed piece by piece. Histologic inspection showed exuberant osteoid trabeculae and immature bone formation by osteoblasts with vascularized connective tissue. We diagnosed the tumor as osteoblastoma based on the clinical presentation and the size of the tumor. No recurrence was evident at the 1-year follow-up visit.

Osteoblastoma of the nasal septum

OBJECTIVES

To present a case of, and to review the literature concerning, osteoblastoma of the nasal cavity, and to demonstrate the importance of considering this rare entity when assessing patients presenting with a nasal septum lesion.

CASE REPORT

Benign osteoblastoma is a rare tumour, constituting 1 per cent of all bone tumours. Most cases occur in the long bones. Osteoblastoma involving the nasal cavity is rare, with only 10 reported cases in the English-language literature. Most nasal cavity cases originate from the ethmoid sinus and spread to involve the nasal cavity. There are only four reported cases of osteoblastoma originating from the bones of the nasal cavity. We report a case of osteoblastoma originating from the bony nasal septum in a 45-year-old man with a history of recurrent, right-sided epistaxis and nasal obstruction.

CONCLUSION

This is the second report in the English-language literature of osteoblastoma originating from the bony nasal septum.

Imaging appearance of bone tumors of the maxillofacial region

This paper reviews the imaging appearance of benign and malignant bone tumors of the maxillofacial region. A benign bone tumor commonly appears as a well circumscribed lesion. The matrix of the tumor may be calcified or sclerotic. Malignancies often display aggressive characteristics such as cortical breakthrough, bone destruction, a permeative pattern and associated soft-tissue masses. Computed tomography scan is an excellent imaging modality for accurate localization of the lesion, characterization of the tumor matrix and detection of associated osseous changes such as bone remodeling, destruction or periosteal reaction. Magnetic resonance imaging is of limited value in the evaluation of maxillofacial bone tumors.

Osteoblastoma of the frontal sinuses presenting with headache and blurred vision: case report and review of the literature

Osteoblastoma is a rare benign bone tumor that usually arises in the vertebral column and long bones of young adults. Craniofacial involvement is extremely rare. To date, osteoblastoma of the frontal sinus has not been reported in the English literature. We report an osteoblastoma of both frontal sinuses in a 23-year-old male who presented with headache and blurry vision in the left eye. Computed tomography (CT) demonstrated an expansile lesion involving both frontal sinuses with sclerotic and fibrous components, eroding into the roof of the left orbit. On magnetic resonance imaging (MRI) the dense portion of the lesion showed signal void on all sequences, while the fibrous matrix was isointense to grey matter on T1-weighted and T2-weighted images and showed avid enhancement following intravenous contrast administration. Surgical resection was performed and histology was consistent with osteoblastoma.

Sino-orbital osteoma: a clinicopathologic study of 45 surgically treated cases with emphasis on tumors with osteoblastoma-like features

CONTEXT

Osteomas are limited almost exclusively to craniofacial and jaw bones. Histologically, they can be divided into ivory, mature, or mixed types. Osteomas may have osteoblastoma-like areas and distinguishing it from true osteoblastoma can be challenging. Some believe osteomas with osteoblastoma-like features behave more aggressively.

OBJECTIVE

To perform a clinicopathologic comparison of sino-orbital osteomas both with and without osteoblastoma-like features.

DESIGN

We studied 45 surgically excised sino-orbital osteomas. Tumors were categorized as ivory, mature, or mixed type and presence of osteoblastoma-like areas and Paget-like bone were noted. Clinical features of those with and without osteoblastoma-like areas were compared.

RESULTS

Men outnumbered women (3:2); median age was 37 years. Frontal sinus was the most common location (62%) followed by ethmoid and maxillary sinuses. Twelve tumors (27%) involved the orbit, 2 primarily and 10 secondarily. All cases were symptomatic with headache, sinusitis, visual changes, pain, and proptosis being most common. Seventeen tumors (38%) had osteoblastoma-like areas. Extension into an adjacent sinus/anatomic compartment was more common in osteoblastoma-like tumors (47% versus 29%), including more frequent orbital involvement (41% versus 13%). Visual changes were more frequent in the osteoblastoma-like group. Distribution of histologic subtypes and Paget-like bone were similar between the 2 groups. Osteomas with osteoblastoma-like features were more often incompletely excised (25% versus 14%). However, clinical recurrence was less common (8% versus 27%).

CONCLUSIONS

Osteoblastoma-like features are common in sino-orbital osteomas, but it does not correlate with more adverse clinical features or worse outcome. Osteoblastoma-like areas appear to represent active remodeling within an osteoma rather than defining a distinct clinicopathologic entity. Distinguishing it from osteoblastoma may require careful histologic evaluation and radiographic correlation.

Osteoblastoma of the ethmoid sinus

An osteoblastoma is a benign bone tumor that most often occurs in the vertebral column and the long bones of the extremities. Paranasal sinus involvement is very rare. We report an osteoblastoma of the ethmoid sinus in a 13-year-old boy who presented with exophthalmos. CT demonstrated an expansile, lesion of the right ethmoid sinus, which caused the orbital contents to be compressed and deviated to the right. A mixture of ground glass opacity and dense bone was present. The less dense portions of the lesion showed intense enhancement on MRI; a signal void was present on all sequences in the densely sclerotic areas. Curettage was performed. Histologically, the lesion was composed of proliferating osteoblasts along with small trabeculae of woven bone and rich vascular fibrous stroma. The literature concerning occurrence of osteoblastoma in this unusual location is reviewed and discussed.

Periosteal osteoblastoma: report of a case with a rare histopathologic presentation and review of the literature

Osteoblastoma is an uncommon benign bone tumor most commonly located in the vertebral column or metaphysis of a long bone. Periosteal location is rare. We report a periosteal-based osteoblastoma, arising from the proximal tibia, in a 20-year-old woman who presented with knee swelling and pain of 2-year duration. Imaging studies showed a metaphyseal surface-based lesion with patchy radiodensities. The cortico-medullary junction was intact. The lesion was totally excised. Histopathologic evaluation disclosed immature bone and osteoid deposition in a vascularized stroma, associated with numerous osteoblasts and osteoclasts rimming the bony trabeculae. Plate-like arrangements of cartilage in the margin of the neoplastic tissue were also identified. At 16 months postoperatively, the patient was well without recurrence. Although extremely unusual, the presence of cartilage does not necessarily exclude the diagnosis of osteoblastoma.