[Useful imaging in maxillofacial surgery. Part II: practical applications]. / L'imagerie utile en chirurgie maxillofaciale. Deuxième partie: applications pratiques.

Various pathologic patterns are discussed with advice on appropriate radiographic imaging. The choice of the most suitable modality for each condition depends on the need to obtain the most accurate results. Panoramic radiography remains a basic and low cost method. Choice of CT or MR as the principal or only modality depends on anatomic patterns: CT being preferred for bone and cavities, MR for soft tissue and cavity content. Much progress has been made in MR machines and the variety of sequences enables high discrimination between normal and pathologic tissues.

[Orbital blow-out fractures]. / Les fractures par enfoncement dites "blow-out" de l'orbite.

Blow-out fractures, lateral fractures of the face, involve only the inferior and sometimes the medial wall of the orbit. Clinical diagnosis is not always obvious, and CT is helpful to confirm diagnosis and also detect some failures of surgical treatment: improper position or size of the graft. MRI is valuable to evaluate post-surgical infections.

[What's useful in maxillo-facial surgery imaging: advantages and disavantages of examination modalities (first part)]. / L'imagerie utile en chirurgie maxillo-faciale: avantages et inconvénients des modalités d'examen (1re partie).

Widespread use of multislice volumic CT and rapid 3D reconstructions as well as MR sequences allowing high-resolution tissue characterization have greatly improved the efficiency of face and neck imaging. Panoramic radiography nevertheless remains highly contributive. Sonography has now replaced the standard sialography for the diagnosis of salivary lithiasis. The quality of MR sialography remains subject to sufficiently salivation into the salivary ducts, but without long-lasting retention increasing protein content. Plain radiographs of the face are now out of date.

[Imaging of facial changes in hyperparathyroidism]. / Imagerie des atteintes faciales de l'hyperparathyroïdisme.

Facial changes in hyperparathyroidism, rarely described, are better depicted at CT imaging. This article reviews the maxillo-mandibular, ocular and temporo-mandibular findings associated with the different types of hyperparathyroidism.

[Imaging of mandibular malformations and deformities]. / Imagerie des malformations et déformations mandibulaires.

Mandibular deformities and malformations are quite various. They are mostly identified by clinical examination, but imaging is very useful for surgical planning. CT imaging is essential to evaluate patients with dystrophies such as fibrous dysplasia, neurofibromatosis, Gorlin syndrome and cherubism. Some growth abnormalities lead to a pseudomalformative appearance. Sequelae and ankylosis from condylar fracture, and unilateral mandibular hypoplasia due to capillary-venous malformation require CT or/and MR evaluation. CT with 3D reformations is performed as a complement to clinical evaluation in patients with other growth abnormalities such as orthognathic problems, hypercondylia, and some malformations like lateral facial clefts. MR is helpful for soft tissue evaluation in patients with Parry-Romberg syndrome and Pierre Robin dysostosis.

[Ectopic parotid gland in the mandible and masseter muscle]. / Ectopie salivaire parotidienne double: mandibulaire et massétérine.

An unusual case of double salivary ectopy of parotid gland is described into the masseter muscle and the mandibular ramus in a 45 year-old patient. He first was seen for a slow course tumefaction of the cheek. Imaging demonstrated the intramasseteric localization of the tumefaction and revealed a bone defect in the upper medial part of the mandibular ramus. The intramasseteric salivary ectopy has been confirmed by histologic examination.

[Sinonasal sarcoidosis: CT evaluation]. / La sarcoïdose nasosinusienne: apport de la tomodensitométrie.

Sarcoidosis uncommonly occurs in the sinonasal system and rarely in the absence of pulmonary disease. The mucosa of the septum and inferior turbinates are mostly affected. The diagnosis is based on endoscopic features, CT findings and finally the histologic appearance of non-caseating granulomas. The characteristic CT appearance consists of multiple mucosal nodules, mostly associated with various sinus fillings and inflammatory rhinitis. Septal perforation, nasal bone osteoporosis or destruction, cartilage destruction and saddle nose deformity can occur in patients with severe disease. However the diagnosis cannot be confirmed solely by CT and other causes of granulomatous inflammation have to be excluded using biopsy.

[Nasosinusal sarcoidosis: 13 cases]. / La sarcoïdose nasosinusienne. A propos de 13 cas.

We report 13 cases of nasosinusal sarcoidosis. Sarcoidosis is a chronic, non caseating granulomatous disease. Nasosinusal involment is rare or exceptional and may be isolated (1 case in our series) or associated (12 cases in our series) with other lesions of the chest, skin, liver, spleen, bone, eyes, salivary glands, peripheral lymph nodes or with neurosarcoidosis. The clinical and CT features are various and often non specific. Nasal biopsy guided by physical examination is easy and constitute the main diagnostic criterion. The course of nasosinusal sarcoidosis is variable and no standard treatment has been established. Response to local or systemic corticosteroid therapy is also variable. The recurrence is frequent after tapering off or interrupting corticosteroids that also have important side effects.

[The masseter: an enigmatic muscle]. / Le Masséter: un muscle enigmatique.

PURPOSE: To try and explain the frequency of pathologic processes involving the masseter muscle. MATERIALS AND METHODS: Anatomical and histological evaluation of the masseter muscle and its partial continuity with the medial pterygoid muscle. Retrospective evaluation of 21 cases of pathology of the masseter muscle imaged by CT and/or MRI. RESULTS: Two main groups of pathology are identified: benign masseter hypertrophy and hemodynamically inactive vascular malformations. Other etiologies are quite varied. Some are secondary to processes involving the nearby mandible and parotid gland. Others, including tumors, involved the masseter muscle in a non specific fashion. CT and especially MRI were quite valuable with accurate diagnosis in 17/21 cases, two of which with the help of clinical data. CONCLUSION: The main question regarding the preferential involvement of the masseter muscle over nearby muscles remains unanswered.

Anatomy and imaging of the deep fat of the face.

The aim of this study is to investigate the deep adipose structures of the face. This study is undertaken on anatomical material dissected or sectioned in the three basic planes and in histological sections. The buccal fat pad is described with its main part and its various extensions implicating several superficial and deep regions of the face. Likewise, the parapharyngeal fat pad in the prestyloid space is described. The histology of the structures is discussed, together with the non-mobilizable nature of the fat. Imaging by MRI shows the shape and relations of these fat pads with the neighboring viscera and muscles and their role as early markers in tumor invasion. Finally, their function, as an intermuscular sliding structure, is highlighted.

[CT imaging of fungal and nonfungal caseous sinusitis. A report of 50 cases]. / Imagerie tdm des sinusites caséeuses fongiques et non fongiques. A propos de 50 observations.

PURPOSE: Evaluate the contribution of CT for the diagnosis of caseous fungal and not fungal sinusitis, mostly of dental origin and often improperly called aspergillus sinusitis. MATERIAL: and methods. About 50 cases of caseous maxillary sinusitis, including 34 fungal sinusitis, the authors analyse the most important CT criteria. All patients underwent thereafter surgery, and the removal material was submitted to mycological investigations. RESULTS: Constructive and destructive modifications of the bone walls, fillings of sinus cavities and middle meatus are aspecific signs of chronicity. Dental origin foreign bodies and microcalcifications are more evocative but also non specific. Only the mycological investigation leads to the diagnosis of fungal and identifies by round fifty percent cases to the exact nature of fungal. CONCLUSION: There are no valid predictive criteria for fungal etiology by CT investigation.

[Imaging of solitary maxillo-mandibular plasmacytoma]. / Imagerie des plasmocytomes solitaires maxillo-mandibulaires.

CT was performed in three patients with plasmacytoma of the maxilla and mandible. CT allows improved depiction of the tumor and associated local invasion and bony destruction but remains non-specific. Histology is mandatory for diagnosis and work-up necessary to confirm the solitary nature of the lesion. Intraosseous intramedullary lesions often evolve to multiple myeloma after a few years whereas extramedullary lesions, commonly involving sinonasal structures, typically remain solitary.

[Polyps and polyposis of the paranasal sinuses]. / Polypes et polyposes des cavités naso-sinusiennes.

Discussion is about the different types of naso-sinusal polyps, isolated inflammatory polyps and some other ambiguous types like inverted papilloma, so-called haemorrhagic polyps, pseudo-polyps and reactional polyps collecting very heterogeneous and various clinical, CT and evolutive entities.

CT appearances of ossicular injuries.

Trauma of the ossicular chain is a frequent complication of temporal bone injury. Skull trauma from blows to the temporal, parietal, or occipital region (with or without fracture of the temporal bone) is the main cause of ossicular injury; other modes of injury are rare. Ossicular injury usually occurs as a dislocation, of which there are five types: incudostapedial joint separation, incudomalleolar joint separation, dislocation of the incus, dislocation of the malleoincudal complex, and stapediovestibular dislocation. Fracture of the malleus, incus, or stapes is uncommon. High-resolution computed tomography is the method of choice for evaluation of ossicular trauma. Joint separation and fracture of the stapes are seen on axial images; coronal images may aid visualization. Both axial and coronal images are needed for evaluation of a dislocated malleus or incus. Fracture of the malleus or incus is detected with axial or coronal images; reformatted images may also be useful.

[Peripharyngeal space. Pathology]. / La région péripharyngée. Pathologie.

Tumors are the most frequent pathological pattern found in the peripharyngeal space. Topographically, intrinsic and extrinsic tumors can be distinguished. Intrinsic tumors are mostly salivary, nervous and vascular. Extrinsic tumors extend from the oral cavity, pharynx and parotid gland. MRI globally gives more impressive results than CT. Diagnosis of the tumor type often remains dubious in intrinsic tumors. CT-guided biopsy is then required.

Posterior lumbar epidural fat as a functional structure? Histologic specificities.

STUDY DESIGN: A topographic and histologic study was done to describe the location of the lumbar epidural fat and to find potential tissular specificities. OBJECTIVES: To search for possible histologic characteristics of posterior lumbar epidural fat, which so far has been described as semifluid tissue, and to determine whether posterior lumbar epidural fat is not a simple incidental tissue. SUMMARY OF BACKGROUND DATA: The lumbar epidural fat on two fetuses was studied. In adults, subcutaneous fat and posterior lumbar epidural fat were taken from seven corpses. The authors obtained 13 posterior lumbar epidural fat pads (two at L1-L2, three at L2-L3, six at L3-L4, and two at L4-L5) and four subcutaneous fat pads. METHODS: The authors studied abdominal axial histologic sections in two fetuses, histologic multiplanar sections in seven adults, and semithin sections in four adults of posterior lumbar epidural fat and subcutaneous fat. RESULTS: Fetal distribution of epidural fat was circumferential. Adult epidural fat distribution was limited to the posterior part of the vertebral canal and located at the disc level. Fascicles of connective tissue were less numerous and thinner in posterior lumbar epidural fat than in subcutaneous fat. Organized sliding spaces were found in the posterior epidural fat ped. CONCLUSIONS: Posterior lumbar epidural fat is not a simple incidental tissue and shows specific histologic features: sliding spaces and rarefaction of connective tissue that could explain semifluid features of the tissue. These characteristics suggest a functional role of posterior epidural fat in the lumbar spinal unit.

The parapharyngeal adipose corpus: morphologic study.

The parapharyngeal adipose corpus is a well limited adipose structure lying deep in the prestylian space, close to the lateral wall of the upper part of the pharynx. Macroscopic and microscopic anatomic sections were made and compared with CT and MR sectional imaging. The walls and contents of the parapharyngeal adipose corpus are described on the basis of anatomic sections and are symmetrically visualized by sectional imaging in the axial and coronal planes. A knowledge of its relations explains its role in imaging as an early marker of invasive tumoral processes. It is in continuity with the upper part of the buccal fat pad and presents the same functional characteristics of a gliding structure.

[Caseous sinusitis. Clinical, x-ray computed, surgical, histopathological, biological, biochemical and myco-bacteriological aspects. Apropos of 33 cases]. / Les sinusites caséeuses aspects cliniques, TDM, opératoires, anatomopathologiques, biologiques, biochimiques et myco-bactériologiques. A propos de 33 cas.

We analyse the most important clinical, CT, surgical, histopathological, biological, biochemical, mycological and bacteriological features of caseous sinusitis, i.e. chronic, poorly symptomatic sinusitis which are resistant to usual treatment. CT shows an opacity of the maxillary sinus with often a hyperdense foreign body (dental overfilling) but no valid predictive criteria for fungal etiology. The endoscopic or surgical procedures point out a caseous mass often called fungal mass or aspergilloma. The biochemical composition of this mass (water, proteins, lipids) is similar to that of tissues surrounding the sinus. The calcium value is variable and shows no correlation with CT imaging. The qualitative and quantitative analysis of the metals (zinc, lead, silver, copper, iron) is of relevance for exogenic origin (dental overfilling). The fungal etiology is inconstant (20 cases) after the mycological investigations. We discuss the nosologic and diagnostic features of caseous sinusitis, fungal or not, and which are often or too often called aspergillosis sinusitis.