A Fire Extinguisher Death: The Macklin Effect.

We present the case of an adult white man found dead in a psychiatric institution with fine white powder (monoammonium phosphate) deposited over the entire face after he insufflated the contents of a dry chemical fire extinguisher. Fine white powder was present within the mouth and sinuses and lined the upper airways. On opening the thoracic cavity, approximately 500 g of fine white powder was present within the right thoracic cavity. The esophagus was ruptured. Traumatic emphysema of the posterior sternum wall was present (pneumomediastinum). The ethmoid bones were fractured by the barotrauma. On polarization of the lung tissue, birefringent material was noted deposited along the bronchovascular sheaths and in a subpleural distribution. Death was probably due to a combination of barotrauma and asphyxia.This case study provides strong evidence in support of the etiology and pathophysiology of the Macklin effect. It also provides for the first visual evidence of the phenomenon.

Ethmoidal encephalocele associated with cerebrospinal fluid fistula: indications and results of mini-invasive transnasal approach.

Anterior skull base defects with encephalocele in adults are quite rare and can be a cause of spontaneous rhinoliquorrhea; however, cerebrospinal fluid (CSF) fistula can be not rarely misdiagnosed for several months or years. Five adult patients affected by ethmoidal encephalocele with CSF fistula were treated in our institute from 2006 through to 2011. Onset of clinical history was represented by rhinoliquorrhea, which was precociously recognized in only 1 patient; in the other 4, it was misdiagnosed for a period ranging from 11 months to 5 years. After clinical diagnosis of CSF fistula and after brain magnetic resonance imaging, ethmoidal encephalocele was evident in all patients; preoperative study was completed by spiral computed tomography scan, to clearly identify the skull base bone defect. All patients were operated on by transsphenoidal endonasal endoscope-assisted microsurgical approach through 1 nostril. The herniated brain was coagulated and removed, and reconstruction of cranial base was performed. Postoperative rhinoliquorrhea or other complications did not occur in any patient at short and late follow-up. All patients were discharged after a few days. Endonasal endoscope-assisted microsurgical approach was effective in exposing and repairing the ethmoidal bone defect; tridimensional vision and wide lateral and superior exposition of the operative field were possible in each patient, thanks to the use of microscope and angulated endoscope.

Histological study of the nasal septal cartilage in BALB/c-bm/bm mouse which spontaneously induces malocclusion.

OBJECTIVES: The BALB/c-bm/bm mouse is characterized by short limbs and short tail attributed to undersulfated glycosaminoglycans. Anterior transverse crossbite sometimes spontaneously appears in BALB/c-bm/bm mice. The BALB/c-bm/bm mouse shows a short nose and cranium. The reason for hypo-growth of anterior craniofacial structures has not been clarified, although the nasal septal cartilage might be related to the growth of anterior craniofacial structures. Therefore, the purpose of this study was to evaluate histological findings of the nasal septal cartilage at the border region of the ethmoid and sphenoid bone in BALB/c-bm/bm mice. MATERIALS AND METHODS: BALB/c mice (wild type) and BALB/c-bm/bm mice with normal occlusion (bm/bm) were used. Sagittal sections of female mice aged 2, 4, and 8 weeks were stained with hematoxylin and eosin for histological analysis. RESULTS: At the border region between the nasal septal cartilage and the ethmoid bone in bm/bm, the area of proliferative zone was significantly smaller than that in wild type. At the border regions between the nasal septal cartilage and both the ethmoid and sphenoid bones, the number of proliferative chondrocytes was significantly smaller. Normal endochondral ossification was not observed at the border region between the nasal septal cartilage and the sphenoid bone in bm/bm. CONCLUSION: The findings suggest that disorder of endochondral ossification in the nasal septal cartilage contributes to the hypo-growth of anterior craniofacial structures in bm/bm.

Orthopedic protraction of the maxilla may affect cranial base synchondroses indicated by increased expressions of growth factors.

OBJECTIVES: To examine the biological adaptation of cranial base synchondroses (CBS) when the maxilla was forward positioned by orthopedic force. SETTING AND SAMPLE POPULATION: The Department of Orthodontics at Shanghai Jiao Tong University. 50 Sprague-Dawley rats, 4 weeks of age, were divided into experimental (n=30) and control groups (n=20). MATERIAL AND METHODS: An orthopedic appliance was fitted to the cranio-maxillary complex to advance the maxilla forward. The animals in the experimental group, together with the counterparts in the control group, were sacrificed at days 1, 3, 5, 7, and 14, respectively. The whole cranial base housing both the spheno-ethmoid (SES) and spheno-occipital synchondroses (SOS) was removed for tissue processing and immunotest of Sox9, Core-binding factor α 1 (Cbfa1), and vascular endothelial growth factor (VEGF), three carefully selected growth factors that are markers of chondrogenesis in different stages and its transition to endochondral ossification. Semiquantitative analysis was also conducted by using a computerizing imaging system. RESULTS: The temporal tendency of the changes in the expressions of the three growth factors featured an increase from Day 3 and onwards for Cbfa1 and VEGF, and a following decline after Day 5 for Sox9. In both SES and SOS, the expressions of the three growth factors were significantly stronger in the experimental groups than that in groups (p<0.05). CONCLUSIONS: Protractive orthopedic force imposed on the maxilla provokes an enhancement of chondrogenic process in CBS.

Changes in width of lower face after unilateral mandibular distraction osteogenesis.

Distraction osteogenesis (DO) has been popular to improve hypoplastic mandible in patients with hemifacial microsomia in craniofacial surgery. However, changes in width of the lower face after DO still lack in literatures. The aim of this pilot study was to evaluate cephalometric changes in width of the lower face at different time points after DO and to give an insight into the influence on facial contour. A total of 10 patients (8 males and 2 females) with hemifacial microsomia received DO of the mandibular body measured by posteroanterior cephalograms. Five landmarks (crista galli, latero-orbitale, gonion of the unaffected side, incisor point superior of the unaffected maxilla, incisor point inferior of the unaffected side of the mandible) were chosen for cephalometric analysis. Six distances from the soft tissue contour perpendicularly to the vertical reference line (through crista galli) were calculated through the incisor point superior of the unaffected maxilla, gonion of the unaffected side, incisor point inferior of the unaffected side of the mandible. Measurements were taken preoperatively and postoperatively on the day distraction started (time 1), at the end of distraction (time 2), and at the end of the consolidation period (time 3). Calculations for statistical significance were done for all patients. Mean differences between 3 periods were measured by repeated-measures analysis with significance determined at the 0.05 level of confidence. The results suggested that the values of 6 distances at times 2 and 3 had no significant differences when compared with the values at time 1 (P>0.05). In conclusion, DO of the unilateral mandibular body in patients with hemifacial microsomia should not be beneficial to improve the width of the lower face at a short-term follow-up.

Morphometric analysis of treatment effects of bone-anchored maxillary protraction in growing Class III patients.

The aim of the present morphometric investigation was to evaluate the effects of bone-anchored maxillary protraction (BAMP) in the treatment of growing patients with Class III malocclusion. The shape and size changes in the craniofacial configuration of a sample of 26 children with Class III malocclusions consecutively treated with the BAMP protocol were compared with a matched sample of 15 children with untreated Class III malocclusions. All subjects in the two groups were at a prepubertal stage of skeletal development at time of first observation. Average duration of treatment was 14 months. Significant treatment-induced modifications involved both the maxilla and the mandible. The most evident deformation consisted of marked forward displacement of the maxillary complex with more moderate favourable effects in the mandible. Deformations in the vertical dimension were not detected. The significant deformations were associated with significant differences in size in the group treated with the BAMP protocol.

Ethmoidal meningoencephalocele in a C57BL/6J mouse.

An otherwise healthy two-month-old female C57BL/6J mouse presented with a left-sided head tilt. Differential diagnoses included idiopathic necrotizing arteritis, bacterial otitis media/interna (Pasteurella pneumotropica, Pseudomonas aeruginosa, Streptococcus sp., Mycoplasma pulmonis and Burkholderia gladioli), encephalitis, an abscess, neoplasia, a congenital malformation and an accidental or iatrogenic head trauma. Magnetic resonance imaging (MRI) revealed a large space-occupying right olfactory lobe intra-axial lesion with severe secondary left-sided subfalcine herniation. Following imaging, the animal was euthanized due to poor prognosis. Histopathologic examination revealed a unilateral, full-thickness bone defect at the base of the cribriform plate and nasal conchae dysplasia, resulting in the herniation of the olfactory bulb into the nasal cavity. There was also a left midline-shift of the frontal cortex and moderate catarrhal sinusitis in the left mandibular sinus. The MRI and histopathologic changes are consistent with a congenital malformation of the nasal cavity and frontal aspect of the skull known as an ethmoidal meningoencephalocele. Encephaloceles are rare abnormalities caused by herniation of contents of the brain through a defect in the skull which occur due to disruption of the neural tube closure at the level anterior neuropore or secondary to trauma, surgical complications, cleft palate or increased intracranial pressure. The etiology is incompletely understood but hypotheses include genetics, vitamin deficiency, teratogens, infectious agents and environmental factors. Ethmoidal encephaloceles have been reported in multiple species including humans but have not been reported previously in mice. There are multiple models for spontaneous and induced craniofacial malformation in mice, but none described for ethmoidal encephaloceles.

Soft tissue images from cephalograms compared with those from a 3D surface acquisition system.

OBJECTIVE: To assess whether 2D cephalometrics is comparable with 3D imaging devices and whether 3D technology could replace traditional 2D image capture in posttreatment evaluation. MATERIALS AND METHODS: The study is a prospective evaluation of superimposition techniques obtained from a cohort of 40 patients who underwent orthognathic surgery in a private practice environment. Surgical records were obtained from lateral cephalometric radiographs taken by a Kodak 8000C machine, and the 3D images were obtained from the 3dMD stereo photogrammetric camera capture system. Pre- and postlateral cephalometric records were superimposed on the cranial base (SN line) while pre- and post-3D surgical records were superimposed on the regional best-fit method. A mathematical algorithm, or best-fit calculation, was carried out on the selected surfaces. Each set of superimposed records was analyzed, and five soft tissue landmarks were plotted. The differences between the five surface points were analyzed for each set of records. RESULTS: The final sample consisted of 34 subjects with full records. A total of 680 surface landmarks were plotted and analyzed. The mean differences of the soft tissue landmarks were analyzed for each pair of data sets and were found to range between 1.06 and 8.07 mm and 1.26 and 7.34 mm for lateral cephalometric and 3D readings, respectively. Paired t-tests were carried out using the SPSS 15.0 software, and they showed that the results were not statistically significant between the superimposition techniques on the image capture systems (P > .05). CONCLUSIONS: The types of superimposition techniques used in the imaging modalities studied were comparable with one another.

Superimposition of 3-dimensional cone-beam computed tomography models of growing patients.

INTRODUCTION: The objective of this study was to evaluate a new method for superimposition of 3-dimensional (3D) models of growing subjects. METHODS: Cone-beam computed tomography scans were taken before and after Class III malocclusion orthopedic treatment with miniplates. Three observers independently constructed 18 3D virtual surface models from cone-beam computed tomography scans of 3 patients. Separate 3D models were constructed for soft-tissue, cranial base, maxillary, and mandibular surfaces. The anterior cranial fossa was used to register the 3D models of before and after treatment (about 1 year of follow-up). RESULTS: Three-dimensional overlays of superimposed models and 3D color-coded displacement maps allowed visual and quantitative assessment of growth and treatment changes. The range of interobserver errors for each anatomic region was 0.4 mm for the zygomatic process of maxilla, chin, condyles, posterior border of the rami, and lower border of the mandible, and 0.5 mm for the anterior maxilla soft-tissue upper lip. CONCLUSIONS: Our results suggest that this method is a valid and reproducible assessment of treatment outcomes for growing subjects. This technique can be used to identify maxillary and mandibular positional changes and bone remodeling relative to the anterior cranial fossa.

Mandibular rotation and remodeling changes during early childhood.

OBJECTIVE: To describe the mandibular rotation and remodeling of younger children. MATERIALS AND METHODS: The sample included 43 males and 43 females who participated in the Bolton-Brush Growth Study at Case Western Reserve University in Ohio. They were chosen on the basis of having Class I (n = 45) or Class II (n = 41) molar relationships and longitudinal lateral cephalograms at three developmental stages of the dentition: late primary (T1: 5.7 +/- 0.5 y), early mixed (T2: 8.4 +/- 0.6 y), and full permanent dentition (T3: 15.4 +/- 0.5 y). Each subject's cephalograms were traced and four landmarks were digitized. Cranial base and mandibular superimpositions were performed with the use of natural reference structures. RESULTS: Yearly rates of true rotation, apparent rotation, and angular remodeling showed significant (P < .05) changes throughout. True rotation was moderately correlated with angular remodeling and apparent rotation. Although no significant sex differences in annual rates of rotation were noted, subjects with Class I molar relationships showed significantly more angular remodeling from T2-T3 than did subjects with Class II molar relationships. Rates of true forward rotation were significantly greater with T1-T2 than with T2-T3 (1.3 and 0.7 degrees/y, respectively). CONCLUSION: Although significant amounts of true mandibular rotation and angular remodeling occur during childhood and adolescence, true rotation is greatest during the transition from late primary to early mixed dentition.

More than meets the eye.

We report an extremely rare case of a hybrid tumour of the maxillary sinus. A 51-year-old man presented with a 6-week history of nasal congestion and epiphora. Radiological imaging demonstrated a maxillary sinus tumour, with extensive local invasion. Surgical excision included maxillectomy, left eye exenteration and free flap closure. Histology of the excised specimen showed a rare hybrid tumour containing adenoid cystic carcinoma, salivary duct carcinoma, epithelial-myoepithelial carcinoma and basal cell adenoma. Hybrid tumours are very rare tumour entities which are composed of at least two distinct tumour types. Each tumour entity conforms with a defined tumour type. The tumour entities of a hybrid tumour are not separated but have an identical origin within a definite topographical area. Diagnosis and appropriate management requires high index of suspicion, pathological endeavour to look for a more aggressive accompanying tumour and adequate oncological treatment according to the highest grade of tumour.

Severe posterior epistaxis-endoscopic surgical anatomy.

OBJECTIVE: To describe the anatomy of the sphenopalatine foramen (SPF) region and possible anatomical variations. STUDY DESIGN: Prospective study accomplished from September, 2006, to January, 2007. METHODS: The sphenopalatine foramen (SPF) of 61 cadavers were carefully dissected. Presence of the ethmoidal crest, location of sphenopalatine and accessory foramens, and the number of arterial branches emerging through foramens were observed. Data were analyzed in relation to gender, racial group, and symmetry of the cadaver. Prediction of the presence of accessory foramen was evaluated. RESULTS: Mixed race cadavers prevailed in 122 nasal fossae dissected (75% males). Ethmoidal crest was present in 100% of the cadavers, being anterior to the SPF in 98.4% of the cases. The most frequent SPF location was the transition of the middle and superior meatus (86.9%). Mean distance from the SPF and accessory foramen to anterior nasal spine was 6.6 cm and 6.7 cm, respectively. Accessory foramen was present in 9.83% of the cases. A single arterial stem emerged through the SPF in 67.2% of the cases, and 100% through accessory foramens. The prevalence analyses showed no differences that were statistically significant (P > 0.05) between gender and racial group. The symmetry analyses showed a strong conformity (P < 0.01) between nasal fossae in relation to the SPF location. There was no statistically significant conformity between nasal fossae and accessory foramen (P = 0.53). None of the variables of interest presents any statistically significant (P > 0.05) association with the presence of the accessory foramen. CONCLUSIONS: There are anatomical variations in the lateral nose wall that should be considered for successful endoscopic surgical treatment of severe epistaxis.

[Giant cell reparative granuloma originating from the paranasal sinus: a case report].

A 40-year-old man presented with a 10-year history of nasal obstruction of his left nose, a 1-year history of headache and orbital pain. Radiologically, an extensive paranasal sinus mass was seen. Superiorly ,the cribriform plate was demineralized, and the lesion had intracranial extension with mild mass effect over the basal frontal lobes. Histologic examination revealed a central giant cell reparative granuloma. After endoscopic removal, the patient was symptom free at the 2-month follow-up.

Endoscopic surgery for fibrous dysplasia of the sinonasal tract in pediatric patients.

Fibrous dysplasia (FD) is a non-neoplastic, expansile lesion of unknown origin. In about one-fourth of cases this disorder affects the head and neck area, where the mandible and maxilla are the most frequently involved sites. Its localization to the ethmoid is a rare event. Since the disease slowly progresses, its management is delayed until significant clinical symptoms or non-well-tolerated aesthetic deformities are present. When required, surgery is the treatment of choice. Several external procedures have been used to manage the lesion, but recently, more conservative transnasal approaches have been proposed. We report the history of a 6-year-old boy with fibrous dysplasia of the ethmoid labyrinth that underwent successful transnasal endoscopic removal. Furthermore, an analysis of the literature is presented with particular emphasis on clinical picture, diagnosis, and treatment of this rare illness.

Frontal plagiocephaly secondary to synostosis of the frontosphenoidal suture. Case report.

Frontal plagiocephaly may arise from either synostotic or deformational forces. Deformational causes of frontal plagiocephaly can be distinguished from synostotic causes by differences seen on physical examination, which can then be confirmed by skull x-ray films and if necessary three-dimensional computerized tomography (CT). Unilateral coronal synostosis is the main synostotic cause of frontal plagiocephaly, although it has also been seen with fusion of the frontozygomatic suture. In several syndromes presenting with bilateral coronal synostosis, fusion of the frontosphenoidal and frontoethmoidal sutures is also present. The authors report, for perhaps the first time, a case showing synostotic frontal plagiocephaly secondary to fusion of the frontosphenoidal suture alone. Although the phenotypic appearance is superficially similar to that seen in unilateral coronal synostosis, analysis of the cranial base shows markedly different effects: angulation of the anterior cranial base with respect to the posterior cranial base away from the synostotic side and angulation of the posterior cranial base with respect to the midpalatal suture also away from the synostotic side. In unilateral coronal synostosis, both angulations are toward the synostotic side. These effects on the cranial base alter its relationship to the cranial vault and the facial skeleton. Most important, frontal plagiocephaly secondary to fusion of the frontosphenoidal suture should not be overlooked as being deformational. Because this fusion is difficult or impossible to visualize by skull x-ray films, three dimensional CT must be obtained in cases that are not clearly identified as deformational plagiocephaly by physical examination.

Histology and histomorphometry of ethmoid bone in chronic rhinosinusitis.

Mucosal changes have been well described in chronic sinusitis, yet little is known about the underlying bone, despite clinical and experimental evidence suggesting that bone may be involved in chronic sinusitis. Techniques of undecalcified bone analysis were used for detailed histologic examination of ethmoid bone in chronic sinusitis compared with controls. Bone synthesis, resorption, and inflammatory cell presence were specifically assessed. Additionally, histomorphometry techniques were used to determine ethmoid bone physiology in individuals undergoing surgery for chronic sinusitis. Overall, individuals undergoing surgery for chronic sinusitis were found to have evidence of marked acceleration in bone physiology with histologic changes including new bone formation, fibrosis, and presence of inflammatory cells. These findings are compared with osteomyelitis in long bone and the jaw. The suggestion that underlying bone may serve as a catalyst for chronic sinusitis is supported and implications for therapy are discussed.

Surgery of the lateral nasal wall and ethmoid: effects on sinonasal growth: an experimental study in rabbits.

OBJECTIVE: To assess the impact of lateral nasal wall surgery on sinonasal growth METHODS: Twenty young New Zealand White rabbits, 6 weeks of age, were included in this experimental study. Surgery was performed on two groups of ten animals each (series I and II). Entrance to the left nasal cavity is achieved through the nasal dorsum via mobilization and rotation of the left nasal bone. Series I: partial resection of the lateral nasal wall (including the ostium to the maxillary sinus) on the left side. Series II: partial resection of the lateral nasal wall and anterior ethmoid. Follow-up period was 20 weeks. Twenty rabbits served as controls. RESULTS: In series I, all skulls have grown normally. In series II the nasal dorsum has also developed symmetrically. Snout length and growth of upper jaw are normal; there is no malocclusion. Three skulls show a slight deviation of the nasal dorsum (two to the left, one to the right). Morphometric measurements of 20 points on the skulls show no significant difference between the control group and the experimental series I and II. CONCLUSION: This experimental study demonstrates that visually controlled partial resection of the bony sinonasal wall, with or without resection of the anterior ethmoid does not affect later development of nose and upper jaw on condition that eventually underlying cartilage is preserved. Contradictory results from other experimental studies, previously published and concerning negative effects of sinus surgery, might be attributed to surgical traumatization of intranasal cartilage structures, in particular, the upper lateral cartilages.

Cystic cemento-ossifying fibroma of the ethmoidal cells (a case report).

A case report of an aggressive cystic cemento-ossifying fibroma of the ethmoidal cells is presented. Fibro-osseous lesions containing cementum are considered to be of periodontal membrane origin and are most common in the mandible and maxilla. Following the WHO classification, fibro-osseous lesions containing cementum are grouped together under the heading of cementoma and are divided into four subgroups. Cemento-ossifying fibroma is considered to be a variant of cementifying fibroma which is a sub-group of cementoma. The unique site of origin seen in this case is thought to have been the result of an ectopic periodontal membrane or of a primitive mesenchymal cell rest or incomplete migration of the medial part of the nasal anlage and differentiation into the periodontal membrane.

The transfacial approach to the postnasal space and retromaxillary structures.

Various surgical approaches to the region are discussed, and the procedure according to Hernandez Altemir (1986) described in detail. Six cases are presented to illustrate how this versatile osteoplastic technique may be adapted for individual patients.