Aneurysmal bone cysts of the head and neck in pediatric patients: a case series

OBJECTIVES: To characterize aneurysmal bone cysts (ABCs) of the head and neck as seen at a tertiary care center. DESIGN: A case series. METHODS: A retrospective chart review of pediatric patients with aneurysmal bone cyst of the head and neck treated at the Hospital for Sick Children during the years 1994-2006 was carried out. RESULTS: Nine patients with ABC were treated. The average age at diagnosis was 9.3 years (range: 5 months-15 years), six males and three females. Four cysts originated in the paranasal sinuses, two in the mandible, one in the zygoma, one in the mastoid and one in the parietal bone. Two cases were associated with a previous localized trauma (mandible, zygoma). 5/9 presented with pain, 4/9 presented as an asymptomatic mass, 2/9 were associated with proptosis and nasal obstruction, 2/9 with nasal obstruction and 1/9 presented with an aural polyp. Seven cysts were successfully excised while one (in the pterygomaxillary fossa) is being followed conservatively. In one case the ABC was found to be secondary to an extensive osteoblastoma and this child continuous to be problematic. Follow-up time ranged from 2 years and 6 months to 10 years. CONCLUSIONS: ABC of the head and neck may vary in presentation and severity. Surgical removal is the treatment of choice at our institution and may provide a satisfying outcome. ABC may be secondary to an underlying bone pathology (e.g., osteoblastoma) which may make it refractory to treatment.     

Osteosynthesis of the temporal articular tubercle

This technical note stresses the interest of the temporal articular tubercle osteosynthesis in zygomatic bone fractures. An impaction of the zygoma can lead to valgus of the temporal bone's zygomatic process with diastasis in the temporal articular tubercle. If the frontal and maxillary processes are comminuted, osteosynthesis of the temporal articular tubercle allows recovering the initial projection of the zygomatic bone. The adequate alignment of the sphenozygomatic suture is also reliable for an anatomical reduction of the fracture.     

Experimental evaluation of relapse-risks in operated zygoma fractures

Objectives

Prevention of relapse, or postoperative dislocation, of the fixed zygoma is necessary to achieve optimal results in the treatment of zygoma fractures. Assuming that the occurrence of intensified stresses on mastication at the screw–bone interface (SBI) constitutes the essential cause of the relapse, we evaluated the stresses for three different fixation methods—fixation at the frontal process (FP), inferior orbital rim (IOR), and zygomatico-maxillary buttress (ZMB).

Methods

We used 10 computer-aided design (CAD) models simulating zygoma fractures in the experiment. For each CAD model, we fixed the fractured zygoma with four screws and one mini-plate at the FP, IOR, or ZMB. After applying a 5.5 kg force simulating mastication, we calculated the intensity and distribution patterns of the stresses occurring at the SBIs of the fixation screws using the finite element method. Thereby, we evaluated dynamic stability of the fixed zygoma for each of the three fixation methods.

Results

Greater stresses occur at the SBIs with IOR fixation than at those with FP and ZMB fixation. Although the stresses occurring at the SBIs on mastication demonstrated evenly distributed patterns with the FP and ZMB fixation, the stresses demonstrated concentration on one screw with the IOR fixation.

Conclusions

The fixed zygoma is more likely to cause relapse with the IOR fixation than with the FP or ZMB fixation. Hence, in performing zygoma fixation at the IOR, care should be taken to minimize the likelihood of postoperative relapse that is caused by skewed distribution of the stresses on the fixation screws.     

Lymphoma of the zygoma: an unusual cause of unilateral facial swelling

Primary lymphoma of bone is a rare clinicopathological entity, but accurate diagnosis is important as the tumor is usually radiosensitive and associated with a good prognosis when locally eradicated. To our knowledge primary non-Hodgkin's lymphoma of the zygoma has not been previously reported. We describe a case in which the radiographic appearances were misleading and computed tomography (CT) was important in diagnosing a malignant lesion. The differential diagnosis is discussed.     

Exostosis of the zygoma. Apropos a case

Exostosis is a benign bony process arising from cortical bone. It is generally localized at the fertile metaphysis of long and some flat bones. Localization to the zygoma and/or the coronoid process is exceptional (5 cases in the world literature). We report an original case of exostosis with isolated zygomatic localization in a 14-year-old girl and review the literature. We emphasize the clinical features and the diagnostic and therapeutic approach in this condition.     

The biomechanics of facial bone fracture.

Selected facial bone locations were impacted to simulate clinical trauma conditions. Locations selected included the nose, zygoma, mandible, maxilla, and frontal bone. The experiment clearly delineate tolerance bands for the facial bones for both sexes. These data should permit the improved design of injury producing structures.     

Ganglioneuroma of the zygoma

INTRODUCTION: Ganglioneuroma is an uncommon benign tumor that arises from the sympathetic nervous system accounting for less than 1% of all soft-tissue neoplasms. CASE REPORT: We report the case of a 22 year-old man who presented a ganglioneuroma localized in the zygoma. DISCUSSION: Ganglioneuroma generally develop in the abdomen or thorax soft tissue. The occurrence of ganglioneuroma in the bone is exceptional. To date less than ten cases have been reported, six of which involved the mandible. We discuss the possible causes of tumor development at this site.     

Solid aneurysmal bone cyst of the mandible

Aneurysmal bone cyst is a rare, rapidly expanding, locally destructive, and often misdiagnosed lesion. It accounts for about 1-2% of primary biopsied bone tumours. About 60-70 cases have been reported in the jaws; particularly the molar regions. Eighty percent of patients are under 20 years of age. Aneurysmal bone cyst exists as a primary or secondary lesion. It may be conventional (95%) or solid (5%). The solid variant is more difficult to recognize. The practical importance of aneurysmal bone cyst lies in the fact that it must be differentiated from malignant tumours: mainly with giant cell tumours and teleangiectatic osteosarcoma.     

Aneurysmal bone cyst of the hyoid.

Aneurysmal bone cyst is a rare lesion usually of the long bones, well documented in the literature. It is a cystic, osteolytic vascular tumour, replete with giant cells and fibrous septa, yet devoid of endothelial lining. It has been reported in the larynx and maxillary sinus. This appears to be the first report of an aneurysmal bone cyst occurring in the hyoid bone.     

Non-communicating arachnoid cyst of the temporal bone presenting as facial nerve paralysis in an infant.

Non-communicating arachnoid cyst of the lateral temporal bone is a rare condition. We present a case of a non-communicating arachnoid cyst of the temporal bone in an infant who presented with a lower motor neuron facial nerve paralysis. The patient was treated by surgical excision of the cyst.     

Infratemporal fossa approach to tumours of the temporal bone and base of the skull.

In spite of the development of a superior (middle cranial fossa) and posterior (translabyrinthine) approach to the temporal bone, tumours situated in the infralabyrinthine and apical compartments of the pyramid and surrounding base of the skull were still a challenge for neurosurgeons and otologists as well. The infratemporal fossa approach closes the existing gap in the surgical management of the most hidden lesions of the temporal bone. The approach features the permanent anterior transposition of the facial nerve, resection of the mandibular condyle and mobilization of the zygoma and lateral orbital rim. Obliteration of the pneumatic spaces of the temporal bone, with permanent occlusion of the Eustachian tube and blind sac closure of the external auditory canal, avoids the danger of post-operative infection and leads to primary wound healing in the shortest time. Three types of infratemporal fossa approach are presented and dicussed on the basis of 51 operated patients.     

Review of pseudocysts and bone lacunae of the jaws

Non-odontogenic cystic lesions and so-called "pseudocystic" lesions of the jaws are reviewed, summarizing most recent data from the literature and with illustrations. Pseudocyst lesions include the aneurysmal bone cyst, the solitary bone cyst and Stafne's lacunae. Non-odontogenic cystic lesions, characterized by the presence of a non-odontogenic epithelial lining, are represented by the nasopalatin cyst, the nasoalveolar cyst and an entity currently covering globulomaxillary, midline palatin, midline mandibular and midline alveolar cysts.     

Symposium on maxillo-facial trauma. 3. Pitfalls in the management of zygomatic fractures

Recognition of various types of zygomatic fractures and their postreduction stability is essential for correct diagnosis and proper treatment of zygomatic fractures. It should be fully recognized that the zygoma, upon dislocation, may rotate around a vertical or longitudinal axis, and may be displaced medially, laterally, posteriorly or inferiorly, and that postreduction stability differs considerably depending upon the direction of rotation or displacement of the fractured zygoma. Diagnosis of the type of zygomatic fracture can be made on the three X-ray views: Waters, submentovertical and Caldwell. The Waters view is the best single view for evaluation of zygomatic fractures. It should be noted, however, that posterior displacement of the zygoma may not be well shown in this view, because the zygoma is often displaced along the course of the X-ray beam. The submentovertical view is indispensable for zygomatic arch fracture (Type II), posterior displacement (Type Vc), and medial and lateral rotation of the zygoma around the vertical axis (Type III, a and b). The Caldwell view is an important view for Type IV fractures which rotate around the longitudinal axis, and Type V fractures with medial (Va), lateral (Vb), and inferior (Vd) displacement. Diagnosis of zygomatic fractures should not depend upon the Waters view alone. Classical Temporal Approach. This approach is simple and most effective for depressed arch fractures but not effective for displacement or rotation of the zygomatic body. Elevation of the zygoma via this route may be hazardous for medial displacement (Type Va) and medial rotation around the vertical axis (Type IIIa). Transbuccal elevation is recommended as the standard initial method for all types of zygomatic fractures except for arch and rim fractures. This approach is particularly effective for posterior displacement (Type VC) and lateral rotation around the vertical axis (Type IIIb). Direct transorbital elevation via infraorbital and zygomatico-frontal incisions should be used when the zygoma is impacted and cannot be reduced or when the fractured zygoma is unstable after reduction. This approach should also be used when there is a suspected blow-out fracture of the orbit. This approach is particularly useful for fractures rotated around the vertical or longitudinal axis (Type III and IV) as well as for inferior displacement of the zygoma (Type Vd). Supraorbital elevation via an eyebrow incision is an effective method for posterior displacement Type Vc), but not for lateral or inferior displacement (Type Vb and Vd) or fractures rotated around the longitudinal axis of the zygoma (Type IV). Direct interosseous wiring is the most dependable and effective method of fixation of the zygoma. As a guide to treatment of zygomatic fractures, the Rowe and Killey classification is superior to the widely accepted Knight and North classification. The author proposes a modified Rowe and Killey classification which will more readily help to predict the postreduction stability and thus help to select the method of treatment according to the type of fracture.     

Hemifacial microsomia

Congenital abnormalities of face emerge as a constellation of malformation of structures which arise from the first and the second branchial arch and the intervening first pharyngeal pouch and the primordia of the temporal bone. When fully expressed, a patient with hemifacial microsomia [Syn: otomandibular dysostosis] exhibits usually unilaterally under developed external or middle ear, mandible, zygoma, maxilla, temporal bone, facial muscles, muscles of masticiation. Many cases however, have been reported where the syndrom is not fully expressed (Crabb 1965).     

Cholesterol cysts of the temporal bone: diagnosis and treatment

Cholesterol cyst (or granuloma) of the temporal bone, a recognized clinical entity distinct from cholesteatoma, is more common than previously thought. Apparently it is caused by obstruction of previously pneumatized temporal bone air cells. Surgical cure is achieved by drainage and reestablishment of normal pneumatization. This paper reviews 14 cholesterol cysts of the temporal bone, emphasizing the importance of preoperative imaging and surgical approach. Use of magnetic resonance imaging differentiates cholesterol cysts from cholesteatoma or other neoplasms. Computed tomography delineates the location of the lesion and defines temporal bone anatomy essential to surgical approach. The two studies together allow the surgeon to properly plan drainage, as in the case of a cholesterol cyst, versus excision or exteriorization, as in the case of cholesteatoma. The infralabyrinthine approach to a petrous apex cholesterol cyst is the procedure of choice when hearing preservation is desired.     

鼻腔鼻窦动脉瘤样骨囊肿1例附文献复习

目的探讨鼻腔鼻窦动脉瘤样骨囊肿(aneurysmal bone cyst ABC)的发病机制、病理、临床表现、诊断及治疗。方法报道1例鼻腔鼻窦动脉瘤样骨囊肿的临床资料并复习相关文献。结果鼻腔鼻窦动脉瘤样骨囊肿在鼻内镜下完整切除。结论发生于鼻腔鼻窦的动脉瘤样骨囊肿非常少见,CT和MRI是作为诊断的主要依据,一般可在鼻内镜下切除。     

A solid variant of aneurysmal bone cyst of maxilla

A solid variant of Aneurysmal Bone cyst is very rare tumour of maxilla. Histopathologically it is very much similar to giant cell granuloma but the radiographic features can influence the pathologic interpretation. A solid variant of anenurysmal bone cyst has been reported in facial bones and it can involve several adjacent bone synchronously (3). Both giant cell granuloma and aneurysmal bone cyst have a propensity for recurrence variably in the 15%–26% range (5).     

高分辨率CT颅中窝径路定位内耳道的解剖研究

目的 研究术前高分辨率CT (high resolution computerized tomography,HRCT)个体化测量,利用颧弓根、棘孔与锤骨头三者的距离关系经颅中窝径路定位内耳道及面神经的可行性.方法18例福尔马林固定的成人颞骨标本,分为A组10耳,B组8耳,常规行HRCT扫描后进行测量.A组行颅中窝径路手术,比较各解剖实测值与CT测量值之间的关系,建立CT数据模型.B组行颅中窝径路手术时在CT测量值辅助下以颧弓根、棘孔及锤骨头为标志物寻找内耳道.采用配对t检验分析两种方法在各解剖结构测量结果间的差异,以P＜0.05为差异有统计学意义.结果 A组中锤骨头与周围重要解剖结构距离的CT测量值与解剖实测值间结果差异无统计学意义(P值均＞0.05).在HRCT辅助下行颅中窝手术时,B组利用颧弓根到锤骨头及棘孔到锤骨头的CT测量距离指导手术,在1.5～3.7 mm范围内均可正确定位锤骨头;8耳中除1耳其内耳道-锤骨头连线与颧弓根-锤骨头参考线夹角为15°,余7耳颧弓根、锤骨头、内耳道均位于一条直线上.结论 颞骨HRCT可以较为真实地反映锤骨头与颧弓根、棘孔、内耳道等解剖结构之间的距离关系.在行颅中窝手术时,可以借助HRCT通过颧弓根及棘孔来定位锤骨头,进而在其他解剖标志点不清时利用锤骨头安全地定位内耳道.     

Aneurysmal bone cyst in the sphenoid bone: treatment with minimally invasive surgery

Aneurysmal bone cysts are vascular lesions that destroy and expand bone. We report a recently treated case of an aneurysmal cyst of the sphenoid bone. A 14-year-old girl presented with frontal headaches, bouts of nausea, and vomiting. Computed tomography and magnetic resonance imaging showed typical features of an aneurysmal bone cyst. Arterial embolization was undertaken before surgery. The endoscopic transnasal procedure used allowed the complete removal of the aneurysmal bone cyst. This use of minimally invasive surgery makes this case of interest to surgeons of the skull base and sinuses.     

Aneurysmal bone cyst of maxilla with ectopic molar tooth – A case report

Aneurysmal cysts of bone are rare non-neoplastic, locally aggressive lesion of bone with propensity for rapid growth, affecting mainly the long bones and spine. It rarely occurs in the head and neck region and within the head and neck mandible (especially the molar areas) is common. Aneurysmal cyst of bone involving the maxilla in the first decade of life is even rarer. We report a case of giant aneurysmal bone cyst of maxilla in eight-year-old male with ectopic molar tooth within the cyst. Is endoscopic excision possible? Endoscopic excision of the cyst was done successfully and no recurrence was noted even after 1 year of follow up.