Handbook Of Head And Neck Imaging Harnsberger Pdf Download
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The perivertebral space is in the midline, in the deep tissues of the neck, and can be identified from the skull base above to the mediastinum below. It is a discrete space completely enclosed by the deep layer of deep cervical fascia. The fascial attachments of the perivertebral space divide it into two areas, the anteriorprevertebral and posteriorparaspinal portions. We made a retrospective analysis of the radiologic and clinical records of 52 patients with lesions in the perivertebral space, to identify the imaging features that mark a lesion as originating in the perivertebral space and define the spectrum of pathology which occurs in the space. Mass lesions present in the prevertebral or paraspinal portions. In the former they usually involve the vertebral body, displacing the prevertebral muscles anteriorly. Epidural extension from lesions in the perivertebral space proper is common. Masses in the paraspinal perivertebral space usually displace the paraspinal muscles away from the spine. We found 9 inflammatory lesions, 29 malignant and 6 benign tumors, and 8 miscellaneous lesions.
Nearly 400 diagnoses that are delineated, referenced, and lavishly illustrated highlight the third edition of this bestselling reference. Dr. H. Ric Harnsberger and his expert author team of Drs. Pat Hudgins, Bernadette L. Koch, and Bronwyn Hamilton provide carefully updated information in a concise, bulleted format, keeping you current with recent advances in head and neck radiology. Succinct text, outstanding illustrations, and up-to-date content make this title a must-have reference for both radiologists and otolaryngologists who need a single, go-to guide in this fast-changing area.
Nearly 400 diagnoses that are delineated, referenced, and lavishly illustrated highlight the third edition of this bestselling reference. Dr. H. Ric Harnsberger and his expert author team of Drs. Pat Hudgins, Bernadette L. Koch, and Bronwyn Hamilton provide carefully updated information in a concise, bulleted format, keeping you current with recent advances in head and neck radiology. Succinct text, outstanding illustrations, and up-to-date content make this title a must-have reference for both radiologists and otolaryngologists who need a single, go-to guide in this fast-changing area.
The suprahyoid neck is frequently the site of many common conditions. Although accessible to clinical exam, some components are better evaluated with imaging; lesions occupying the sublingual space and submandibular space are invisible to the referring clinician. A broad array of pathological processes can occur in these spaces and pinpointing the origin can narrow the differential and in certain cases determine the diagnosis. These lesions can be classified into congenital, infectious/inflammatory, vascular and neoplastic processes. Typically, computed tomography (CT) or magnetic resonance imaging (MRI) are used for evaluation, but there may be cases where both are needed in conjunction. This review article discusses the relevant anatomy, clinical highlights and the characteristic imaging features of the various pathologies that occur within the sublingual and submandibular spaces.
True dermoid cysts (also known as benign cystic teratomas), epidermoid cysts and teratoid cysts represent a spectrum of congenital and acquired cystic malformations sharing the common characteristic of a squamous epithelial lining. Dermoid cysts as a term refers to three histologically distinct processes classified based on whether they are lined with simple squamous epithelium (epidermoid), skin appendages (dermoid) or tissues of other major organs (teratoid). Dermoids and epidermoids arise from dermal elements of the first and second branchial arches [1, 6]. It is important to distinguish dermoid and epidermoid cysts apart from teratoid cysts, as the former harbour a lower risk of malignant degeneration [7]. Although rare within the head and neck, dermoid and epidermoid cysts have a predilection for the oral cavity, specifically the floor of the mouth [8]. Dermoid cysts typically present in the 2nd or 3rd decade of life as a slowly enlarging midline neck mass, which may progress to cause dysphagia, while epidermoid cysts manifest earlier in life, becoming evident in infancy.
Although vascular malformations commonly occur in the head and neck, they are rare within the sublingual and submandibular spaces. Congenital in nature, these lesions are present at birth, but are discovered later in life as they grow with the patient. They are classified based on the primary constituent channel and rate of flow, with resulting distinctive imaging characteristics (Table 3). Slow-flow lesions consist of lymphatic, venous and venolymphatic networks, while high-flow lesions exploit an arteriovenous communication. Initial evaluation may be performed with ultrasound; however, complete characterisation requires CT or MRI [26].
Characterised by slow vascular flow, this category predominantly consists of venous-based lesions or venous malformations, which most frequently involve the floor of the mouth or buccal space when they occur in the head and neck [13]. Histologically, they are composed of a mass-like collection of venous sinusoids. On initial evaluation, typically by ultrasound, they appear as compressible mixed echogenicity structures with ill-defined margins and monophasic low velocity flow on Doppler interrogation. CT and MRI are used to evaluate spatial extent, visceral involvement and osseous destruction [27]. On MRI, signal patterns depend on vessel size and range from hyperintense venous lakes to more solid appearing lesions that are isointense to muscle on T2-weighted imaging. CT attenuation follows a similar pattern [13]. Characteristic features of any venous-based anomaly, such as phleboliths or diffuse venous phase enhancement, are also present [1].
The diagnostic accuracies of the imaging studies should be clearly acknowledged in managing head and neck cancer patients; however, the accuracies of preoperative imaging studies in detecting retropharyngeal lymph node (RPLN) metastasis are still not clarified. This study was to evaluate diagnostic accuracies of computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT) in detecting RPLN metastasis of head and neck squamous cell carcinomas.
For 123 patients who had performed RPLN dissection during the surgery of their squamous cell carcinoma of the head and neck, preoperative CT, MRI, and/or PET-CT were reviewed for RPLN metastasis in a blinded fashion by one experienced radiologist. Sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of each imaging modality were assessed, by comparing with the histopathologic findings of the resected RPLNs that served as the standard of reference.
RPLN dissections was performed in accordance with the guidelines of our institute. Therapeutic RPLN dissections was performed in patients undergoing surgical treatment of head and neck cancer with imaging studies suggestive of RPLN metastasis. Elective RPLN dissections was performed in patients undergoing head and neck cancer surgery who had a high risk of occult RPLN metastasis; those with advanced carcinoma of the oropharynx and hypopharynx (T3 or T4), tumor extension to the posterior and lateral pharyngeal walls, or multiple-level neck node metastases [1, 17, 19].
Patients with RPLN metastasis have poor prognosis [1,2,3,4]. Our institute has previously reported that oropharyngeal squamous cell carcinoma patients with RPLN metastasis have a significantly lower disease-specific survival rate than those without RPLN metastasis [19]. A positive RPLN on a preoperative image is an independent risk factor associated with RPLN metastasis in multivariate analysis [19]. However, there is still no convincing evidence that RPLN dissection improves survival or regional control in head and neck squamous cell carcinoma [6].
The reported diagnostic values of the three imaging modalities vary widely. Our study is the first one to evaluate their diagnostic values together with pathologic confirmation. The sensitivity of CT was lower than that of the other imaging modalities, which indicates that CT alone is not sufficient to detect RPLN metastasis. The diagnostic accuracy and sensitivity of MRI in our study were slightly higher than those of CT, in line with the previous reports. The sensitivity of PET-CT was higher than that of MRI or CT, but the specificity of PET-CT was the lowest. Interestingly, the sensitivities of the three imaging modalities were lower than their specificities, even in PET-CT (however, MRI findings can be rather suboptimal on this point). This implies that a lower size cutoff may improve sensitivity. Metastasis in RPLNs was revealed in about 10% of the patients who underwent elective RPLN dissection, indicating that close attention should be paid to RPLNs even if preoperative imaging does not suggest positive findings, especially in patients with advanced head and neck cancer. Importantly, when the three imaging modalities were all used preoperatively, the sensitivity and diagnostic accuracy were the greatest, meaning that we can minimize missed diagnoses of RPLN metastasis by using all three modalities for preoperative imaging studies. The difference in the accuracies between new and recurrent cases was not significant, which may be due to the advancement of imaging technology or the strict inclusion criteria for recurrent cases in our study: we included only those who had prior therapy at least 1 year before the recurrence, because the accuracy of imaging studies can be affected by prior treatments.
One limitation of this study is its retrospective nature. Selection bias can be another limitation, as not all the patients with head and neck squamous cell carcinoma were explored for RPLNs (i.e., those who had no indications for RPLN dissection could have been overlooked). However, our study included even patients without radiologic evidence of RPLN metastasis who underwent elective dissection (i.e., high-risk patients); such patients are not usually included in similar studies, and their inclusion may decrease the bias. Micrometastases could have been missed on routine histopathological examination; therefore, the real sensitivity may be lower. Lastly, the diagnostic cutoff values for size and SUV used in this study can be debated, and their values could influence the results. The diagnostic accuracies of different cutoff values for size and SUV were not assessed in this study; to improve reliability, various cutoff values should be investigated. Further prospective studies with larger sample sizes that would include various cutoff values for size and SUV, or use the three imaging modalities for each node positive on histology, could provide more precise information that would be beneficial to this field of medicine. 153554b96e
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