tailieunhanh - Ebook Diagnostic imaging head and neck (2nd edition): Part 2

(BQ) Part 2 book "Diagnostic imaging head and neck" presents the following contents: Sinonasal cavities and orbit (orbit, nose and sinus), skull base ( skull base and facial trauma, skull base lesions), temporal bone and CPA-IAC (introduction and overview, external auditory canal, middle ear mastoid,.). | Diagnostic Imaging Head and Neck Part IV - Sinonasal Cavities and Orbit Section 1 - Nose and Sinus Introduction and Overview Sinonasal Overview Table of Contents Part IV - Sinonasal Cavities and Orbit Section 1 - Nose and Sinus Introduction and Overview Sinonasal Overview Sinonasal Overview Michelle A. Michel MD Summary Thoughts Sinus and Nose The anatomy of the sinonasal SN cavities is as unique as a person s fingerprints. The nasal cavity NC is centrally located and is surrounded by the paranasal sinuses PS . Because the SN region is comprised of air-filled spaces and complex bony architecture CT is often the first-line imaging modality. CT is used for determining the extent of disease and is also helpful for surgical planning and intraoperative guidance. As in all regions of the H N information such as patient demographics presenting symptoms and clinical exam findings are critical for interpreting imaging studies of this area. It is important to understand the drainage pathways of the PS as one can then predict patterns of disease based upon the point of an obstructing lesion. Inflammatory disease is by far the most common pathology. However isolated inflammatory disease of the sphenoid sinus is unusual and should raise suspicion for other pathologies including neoplasm or cephaloceles particularly if there is an associated bone defect. Fortunately malignancies of the SN cavities are rare. They tend to present at an advanced stage and are often in close proximity to vital structures orbit cranial nerves and skull base . These tumors are difficult to completely resect and are associated with high surgical morbidity. Presurgical tumor mapping in such cases is best accomplished with multiplanar MR. Imaging Approaches and Indications CT is the modality of choice for evaluation of inflammatory disease. CT is more sensitive for detecting Ca in lesions fibro-osseous lesions inverted papilloma esthesioneuroblastoma and for evaluating changes in adjacent bone. Coronal .