CT findings of bacterial discitis and osteomyelitis include loss of disk space height and erosion of the adjacent vertebral endplates (62). However, the symptoms of cervical spine disease may mimic those of extraspinal entities, prompting the use of neck CT with a soft-tissue protocol. CT is more sensitive than chest radiography for detection of pneumonia. There is also a large group of lymph nodes in the chest and abdomen, which are sometimes found to be enlarged on X-rays or CT scans. There is coalescence of the right mastoid air cells (black arrow) with breakthrough of the overlying cortex (white arrow). Axial (a) and coronal (b) contrast-enhanced CT images show bilateral low-attenuation collections (arrows) superolateral to the palatine tonsils (* in b). Minor variations to the above anatomic boundaries have been described. Figure 2a. In keeping with lymphatic drainage patterns, the location of a nodal metastasis can suggest the site of a primary head and neck malignancy. They function as filters, trapping viruses, bacteria and other causes of illnesses before they can infect other parts of your body. Sialadenitis in two patients. Because there are components of the respiratory, digestive, vascular, endocrine, skeletal, and neurologic systems in the neck, the radiologist is required to have knowledge and an understanding of how disease manifests and how an abnormality in one system can spread and affect other systems. Neck dissection classification update: revisions proposed by the American Head and Neck Society and the American Academy of Otolaryngology-Head and Neck Surgery. In patients with pneumatized petrous apices, petrous apicitis, a condition analogous to mastoiditis, can develop in the petrous apex (61). In this article, we describe a 12-item checklist-based approach, informed by the space-based approach, that can be used to address the complex anatomy and variety of possible abnormalities that can be seen in the nontraumatic emergency setting (Table). (a, b) Acute right submandibular sialadenitis in a 57-year-old woman. When cavernous sinus thrombosis occurs, there is outward bulging of the normally straight or concave lateral wall of the cavernous sinus, with filling defects in the sinus that correspond to clots (66). Subcutaneous edema (arrows) also is present. Pneumonia appears as nodular and/or consolidative opacities in the lung parenchyma. Sagittal contrast-enhanced CT image shows prevertebral edema (*). The node is enclosed in a capsule and has an indentation on one surface (along one of its long axes) known as the hilum.The hilum is the point at which arteries carrying nutrients and lymphocytes enter the lymph node and veins leave it. Therefore, at many institutions, intravenous contrast material is not administered for this indication. Visible Human Project . Interpreting imaging findings in this fashion enables consistent identification of all findings and clear reporting of the disease process. If the infected nodes rupture, a retropharyngeal abscess forms. 2005;5 Spec No A : S57-67. Lymph nodes in the groin region are referred to as inguinal lymph nodes. Also, when the carotid artery has a medial course, this variant should be noted because it may be mistaken clinically for tonsil-related disease, or the artery may be injured in a tonsillar intervention (23). Valves, which are visible in the internal jugular veins occasionally, and heterogeneous enhancement due to the mixing of opacified and nonopacified blood should not be mistaken for thrombosis. ■ Identify common pathologic entities found at neck CT in the emergency department. Accessory parotid tissue often can be seen along the course of its duct (Stensen duct) superficial to the masseter muscle. In the setting of suspected cervical spine disease, dedicated CT or MRI of the spine is preferred over neck CT. This defect leads to the formation of a false lumen, which is frequently accompanied by narrowing or occlusion of the true lumen (51). For example, with respect to "level VII," radiologists may apply this label to superior mediastinal nodes 2, radiation oncologists may apply this label to "prevertebral nodes" 3, and head and neck surgeons omit this level from their nomenclature altogether 1. Periodontal abscess in a 50-year-old man. (a, b) Acute right submandibular sialadenitis in a 57-year-old woman. Subcutaneous edema of the involved side should be included in the “Cutaneous and Subcutaneous Soft Tissues” section. Usually, diagnosing them means pinpointing what’s causing the swelling. Apple cider vinegar: You may also be able to treat swollen lymph nodes in neck with apple cider vinegar. Figure 17b. Contrast-enhanced CT of malignant otitis externa will reveal extension of the infection to the bone and soft tissue outside of the EAC, with bone erosion of the EAC; soft-tissue infiltration of the infratemporal fossa; erosion, widening, and infiltration of the temporomandibular joint; soft-tissue infiltration along the eustachian tube and within the nasopharynx; and bone erosion within the petrous apex and mastoid process (Fig 1) (7,10). Culture analysis revealed α-hemolytic Streptococcus as the causative organism. There is usually bilateral involvement, which may lead to airway obstruction at the level of the oral cavity and oropharynx (4). The danger space is a well-described potential space between the alar fascia anteriorly and the prevertebral fascia posteriorly. In the acute phase, the lymph nodes are enlarged and homogeneously enhance at CT. As caseation occurs, the nodes become centrally hypoattenuating and cystic, with perinodal fat stranding that is milder than what is seen with bacterial adenitis (Fig 15). The teeth and surrounding structures are common culprits in cases of head and neck infection and are linked to systemic disorders such as cardiovascular disease (31,32). Axial contrast-enhanced CT scans of neck through thyroid gland shows oblique white line drawn on each side of neck through posterolateral margin of anterior scalene muscle (A) and posterior margin of sternocleidomastoid muscle (Sc). When decay reaches the pulp chamber of the tooth, the pulp becomes infected, pressurized, ischemic, and ultimately necrotic. (a) Sagittal contrast-enhanced CT image in a 41-year-old man shows a normal epiglottis (arrow) measuring 2–3 mm in thickness. There is also thickening of the left platysma muscle (arrow). Residual thymic tissue should not be confused for disease, particularly in children and young adults (71). The oral cavity (black * in b) is obliterated. The diagnosis of Lemierre syndrome (discussed earlier) is used to illustrate this synthesis process (Figure E15). Periodontal disease—that is, inflammation of the gingiva (gums)—can progress to periodontitis, in which the periodontal ligament that connects the tooth to the alveolar process, as well as the bone of the alveolar process, is lost (Fig E8). (c) Sagittal nonenhanced CT image (bone window) shows calcification (arrow) inferior to the anterior arch of C1, in the typical location for calcific tendinitis of the longus colli. Cranial nerves V, VI, and IX–XII also may be affected as infection spreads in the soft tissues (7). However, when a lymph node is greater than 1 centimeter in diameter, it is enlarged.. Furthermore, mucosal thickening can persist for 8 weeks following the resolution of sinusitis (56). Traditionally, infectious etiologies are the main cause of lymphadenitis. Viral infections are the most common cause of reactive adenopathy in children and young adults. Left frontal sinusitis and left frontal lobe abscess in a 22-year-old man. Manifestations may be minor conditions such as lip swelling or severe conditions such as laryngeal edema. The esophageal wall should not be thickened. Calcific tendinitis of the longus colli, technically a prevertebral process, results from an inflammatory reaction to hydroxyapatite deposits within the longus colli muscle or tendon (27). In Lemierre syndrome, septic thrombophlebitis of the internal jugular vein occurs secondary to a pharyngeal infection such as pharyngitis or PTA (Fig 17). Figure 5b. We conclude by describing an approach to integrating the findings of the individual checklist items to derive a coherent diagnosis, which is reported in the “Impression” section of the report. A soft plaque (white arrow) causing mild luminal narrowing also is present at the carotid bulb, with possible enhancement of the adjacent vessel wall. (a) Axial nonenhanced CT image (bone window) shows an opacified left frontal sinus, with thinning of the posterior wall of the sinus (arrowhead). Axial nonenhanced CT images show the radiodense bone (black arrows) in the cervical esophagus, posterior to the larynx. It is important to note that due to the angioinvasive nature of this process, extension to adjacent structures may occur even with intact bony sinus walls and minimal mucosal thickening (57). Viral sialadenitis, most commonly mumps, typically (in 85% of cases) occurs in children younger than 15 years and is bilateral in 90% of cases (44). If you feel lumps accompanied by tenderness, you may have swollen lymph nodes. (a) Sagittal contrast-enhanced CT image in a 41-year-old man shows a normal epiglottis (arrow) measuring 2–3 mm in thickness. The left superior ophthalmic vein (black arrowhead) is dilated and not enhanced. Atherosclerosis of the cervical arteries, particularly at the carotid bulbs, is extremely common in middle-aged and older adults and can be evaluated by using multiple modalities, including CT (50). This information can be helpful to the emergency and admitting physicians, particularly when the diagnosis was not made at chest radiography. A periodontal abscess is a focal pocket of pus that forms adjacent to a tooth owing to the direct spread of infection, such as pericoronitis, or following a bony breakthrough of periapical disease into adjacent soft tissues. However, when a lymph node is greater than 1 … Numerous common and clinically significant pathologic conditions may be seen in the lung apices at neck CT. The Delphian lymph node in thyroid cancer. A retropharyngeal abscess is a larger rim-enhancing collection that is not confined by the boundaries of the lymph node; rather, it extends across the retropharyngeal space ( Fig 5 ) ( 24 ). Such nodes usually result from a spread of cancer on the scalp or back of the neck. The subcutaneous tissues may be the primary site of inflammation or an indication of adjacent inflammation. The enlargement may be asymmetric (39). Fungal sinus disease includes allergic fungal sinusitis and invasive fungal sinusitis. Ninety percent of cases of viral sialadenitis involve the parotid glands, while 10% also involve the submandibular glands (44). There is also thin enhancing material in the anterior epidural space extending from the C1–C5 vertebrae (arrows), consistent with epidural phlegmon. Wooden foreign bodies have air attenuation in the acute phase and therefore are best detected by using lung windows, and they may mineralize and increase in attenuation with time (30). References Grégoire V, Ang K, Budach W, Grau C, Hamoir M, Langendijk JA, Lee A, Le QT, Maingon P, Nutting C, O'Sullivan B, Porceddu SV, Lengele B. Delineation of the neck node levels for head and neck tumors: a 2013 update. The lymph node levels of the neck (Robbins) is the most often employed and was published in 1991 by the American Head and Neck Society and the American Academy of Otolaryngology-Head and Neck Surgery.The system was revised in 2002 and 2008. Lymph nodes are bean-shaped structures about 0.1 – 2.5 cm in length. Brain (diagrams) Illustrations. Swollen lymph nodes usually occur as a result of exposure to bacteria or viruses. Additional images (not shown) did not show a stone within or along the course of the parotid duct. Figure 6a. The classic location of second branchial cleft anomalies is anterior to the sternocleidomastoid muscle, at the angle of the mandible; however, different types may manifest along a line between the oropharynx and the supraclavicular region (11). Still, risk factors for development of thyroid abscesses include immunodeficiency and underlying gland abnormalities such as thyroid nodules, thyroid cancer, and fourth branchial cleft anomalies. Radiography may be unreliable, yielding false-positive and false-negative results. - see reference below. It is important to note that the presence of intrasinus fluid or mucosal thickening is not specific for acute sinusitis and may also be seen, for example, in the setting of upper respiratory tract infection or nasogastric tube placement. (a) Axial contrast-enhanced CT image (bone window) shows left tympanomastoid opacification (*), as well as opacification and coalescence of air cells at the petrous apex (white arrow). Jugular thrombosis may be complete, in which case the vein is nonopacified and usually enlarged (when acute), or partial, in which case a sharply marginated filling defect is seen. (a) Axial contrast-enhanced CT image shows a left retropharyngeal low-attenuation lymph node (arrow), consistent with internal suppuration. (2007) Acta oto-laryngologica. Bony breakthrough occurs at weak points of the alveolar process, which include the buccal surface throughout the maxilla and the lingual surface in the area of the mandibular molars. Dental caries appear on CT images as a defect or channel in the highly mineralized enamel of the tooth (Fig E7). If the superior ophthalmic vein is not thrombosed, it becomes enlarged owing to impaired drainage into the cavernous sinus (Fig 22). With few exceptions, neck CT should be performed with intravenous contrast material, which accentuates abnormally enhancing phlegmonous and neoplastic tissues and can be used to delineate any abscesses or necrotic areas. Although primary vascular inflammation is a relatively rare cause of neck pain, it is occasionally identified at neck CT. Cervical arterial inflammation may reflect a systemic large-vessel vasculitis such as Takayasu arteritis. Malignant otitis externa of the right ear in a 55-year-old man. Infection spreads by means of contiguous extension and can lead to mediastinitis if left untreated. Subcutaneous edema (white arrowheads) also is present. Acute invasive fungal sinusitis is characterized by unilateral destruction of the osseous margins of the sinus, with extension into adjacent structures such as the orbits, intracranial compartment, and subcutaneous tissues. Normal internal jugular veins are frequently asymmetric in caliber. Figure 25a. (c) Axial contrast-enhanced CT image (lung window) obtained inferior to a shows a nodular opacity (arrow) at the left lung apex, consistent with a septic pulmonary embolus. Figure 15. Thyroid goiter in a 56-year-old woman. In children, most commonly those between the ages of 2 and 4 years, retropharyngeal abscess is due to an upper respiratory infection or otitis that leads to enlarged lateral retropharyngeal nodes, which lie between the distal cervical internal carotid artery laterally and the prevertebral musculature medially (Fig 5), with subsequent suppuration and intranodal abscess formation (25). Figure 2b. The major salivary glands include the parotid, submandibular, and sublingual glands. Mediastinal masses also may be detected on neck CT scans. (a) Axial nonenhanced CT image (bone window) shows an opacified left frontal sinus, with thinning of the posterior wall of the sinus (arrowhead). Ludwig angina in a 26-year-old man. Noninfectious processes occasionally mimic the findings of discitis and osteomyelitis and should be considered if paraspinal inflammatory changes or abscesses are absent (63). The pneumatized spaces of the head and neck include the paranasal sinuses, which communicate with the nasal cavity, and the mastoid air cells, which communicate with the tympanic (middle ear) cavity. After completing this journal-based SA-CME activity, participants will be able to: ■ Describe how to systematically interpret the findings of neck CT performed in the emergency department. (c) Coronal contrast-enhanced CT image at the level of the parotid glands in a 22-year-old woman with acute left parotiditis shows edema, enlargement, and hyperenhancement of the left parotid gland (white arrowhead). Bacterial infections typically cause more prominent nodal enlargement and also cause surrounding inflammatory change. There is also erosion of the anterior margin of the glenoid fossa (black arrow). 125 (4): 388-96. elevators, retractors and evertors of the upper lip, depressors, retractors and evertors of the lower lip, embryological development of the head and neck. CT is 100% sensitive and 75% specific for detection of PTA, which on CT images most commonly appears as a rim-enhancing collection superolateral to the palatine tonsil (Fig 4) (21). Epidural abscess and subgaleal phlegmon in a 13-year-old boy. The danger space is a potential space that extends from the skull base to the diaphragm. Acute invasive fungal sinusitis typically occurs in immunocompromised patients and can be rapidly progressive and life-threatening (57). Arterial dissection is characterized by a defect in the intimal layer of the artery that allows passage of blood into the arterial wall. Bilateral PTAs in a 21-year-old woman. Malignant otitis externa of the right ear in a 55-year-old man. They decided to do a procedure called a modified radical neck dissection, where lymph nodes and other tissues under the neck (where cancer cells … Goiter refers to enlargement of the thyroid gland. Use the first 3 fingers of both hands simultaneously to circle behind the ears, down both sides of your neck, and under your jaw line. Figure 19a. Although acute conditions are the first that come to mind, malignancy must remain in the differential diagnosis. If there is an obstructing ductal stone (Fig 14), ductal dilatation also is present. Figure 18. Lymph node imaging: multidetector CT (MDCT). As part of the evaluation, the vascular structures and aerodigestive tract must be scrutinized, particularly for patency. As mastoiditis progresses, the mastoid septa become eroded. Axial contrast-enhanced CT image shows a centrally hypoattenuating cystic lymph node (black arrow) with minimal surrounding fat stranding. Seventy-five percent of the time, scrofula is unilateral. In some people, pneumatized spaces extend to the apical (medial) portion of the temporal bone and are termed petrous apex air cells. Noninfectious etiologies are usually the main cause of lymphadenopathy; however, there can be overlap. At imaging, the epiglottis and aryepiglottic folds should be thin (Fig 2). (b, c) Sagittal (b) and axial (c) contrast-enhanced CT images in a 21-year-old man with epiglottitis show thickening of the epiglottis (arrow in b) and aryepiglottic folds (arrows in c). When these glands are enlarged owing to hyperplasia or adenoma, they may be detected at CT. Also known as lymph glands, lymph nodes remove cell waste and fluids from lymph (lymphatic fluid), and store lymphocytes (white blood cells). (a) Axial contrast-enhanced CT image shows foci of gas and fluid (white arrows) in the left submandibular space, with extension to the danger space (black arrows). MRI is useful for evaluating intracranial extension of mastoiditis. The last category of dental infection is pericoronitis, in which food material becomes trapped under a gum flap, commonly in the setting of a partially erupted third molar, and causes acute inflammation and infection (Fig E9). Figure 1b. Ludwig angina in a 26-year-old man. 134 (5): 536-8. Figure 21. CONCLUSION: Necrosis, an ill-defined margin, and heterogeneous enhancement of enlarged lymph nodes in the neck are relatively common CT features of PTCL. There is bone erosion of the anterior wall of the right EAC, which is also the posterior wall of the temporomandibular joint (black arrowhead). Associated imaging abnormalities may include mural thickening of the affected carotid artery and stranding of surrounding fat (Fig 16) (52). Cancer Imaging. For this journal-based SA-CME activity, the authors, editor, and reviewers have disclosed no relevant relationships. (a) Axial contrast-enhanced CT image shows a left retropharyngeal low-attenuation lymph node (arrow), consistent with internal suppuration. Images with a thickness of 2.5 mm are constructed in the axial, sagittal, and coronal planes by using a soft-tissue kernel and in the axial plane by using a bone kernel. As a last point, either clinical or imaging follow-up or tissue sampling may be necessary to make a definitive diagnosis. Head (CT) CT. (2002) Archives of otolaryngology--head & neck surgery. Owing to the lack of contrast enhancement, an abscess cannot be discerned. Lymph nodes that lie near the surface of the skin, such as in the neck, armpit, groin, and sometimes those in the arm (elbow) and back of the knee may be felt when enlarged, but others may only be seen on imaging studies such as a CT scan. Interpreting findings seen at CT of the neck is challenging owing to the complex and nuanced anatomy of the neck, which contains multiple organ systems in a relatively small area. This may be a sign that … Chong V. Cervical lymphadenopathy: what radiologists need to know. Ludwig angina is one of the most feared complications of dental infection. Therefore, in the acute setting, careful inspection of the cervical spine is mandatory at neck CT. Bacterial infection of an intervertebral disk, or discitis, is typically accompanied by infection of the adjoining vertebrae (osteomyelitis) and may be due to hematogenous seeding, direct spread from retropharyngeal or paraspinal infection, or inoculation by way of spinal instrumentation. Inflammatory changes of the paraspinal soft tissues also are usually present and include obscuration of paraspinal fat planes, paraspinal abscesses, and retropharyngeal edema (Fig E11). Normal epiglottis versus epiglottitis in two patients. The parotid gland is the only salivary gland that contains lymph nodes. Additional similar lesions were seen on other images (not shown). Differing definitions exist across specialties 1-4. Figure 8b. I was referred to the haematology unit and the doctor said I would need a CT scan, my results came back and I was advised I would need a biopsy of the area as there was more than 1 node enlarged. If "level VII" is used for superior mediastinal lymph nodes, it should refer to the extension of the paratracheal chain below the suprasternal notch but above the level of the brachiocephalic artery 4. For patients with cervical lymph node enlargement, the presence of these findings may suggest high-grade non-Hodgkin’s lymphoma, including PTCL. Planes and motions (diagrams) Whole head. Odontogenic sinusitis in a 50-year-old man. Bacterial sialadenitis may be complicated by the formation of a rim-enhancing abscess or multiple small abscesses. ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. Unable to process the form. Retropharyngeal edema due to calcific tendinitis of the longus colli in a 71-year-old woman. Branchial cleft anomalies can manifest as a cyst where there is no internal or external connection, as a sinus where there is only an external connection, or as a fistula where there are openings on the skin and pharyngeal surfaces (11). Intraparotid ducts typically are not visible unless they are dilated. In fact, contrast material may obscure or confound the detection of a small foreign body. Important aortic disease can be detected incidentally at neck CT performed in the emergency department. Axial contrast-enhanced CT image shows a homogeneously enlarged thyroid gland (*). Another lymph node (white arrow) has ruptured and fistulized to the skin. In comparison, the left submandibular gland (white arrowhead) is normal. Rarely, swollen lymph nodes are caused by cancer.Your lymph nodes, also called lymph glands, play a vital role in your body's ability to fight off infections. Multiplanar CT and MRI of collections in the retropharyngeal space: is it an abscess? Aortic dissections, penetrating ulcers, and large atheromas are other aortic pathologic conditions that can be seen at neck CT and are important to recognize. The goals in CT scanning of the neck are to allow sufficient time after contrast administration for mucosa, lymph nodes, and pathologic tissue to enhance, yet acquire images while the vasculature remains opacified. Axial contrast-enhanced CT image (a) shows an enlarged hyperenhancing right submandibular gland (black arrowhead) with internal and surrounding edema (black arrow) and overlying thickening of the platysma muscle (white arrow). This is completely normal. Autonomic nervous system … Infection typically spreads from the tympanic cavity to the air cells in the petrous apex, and it may lead to osseous erosion and subsequent involvement of adjacent skull base structures. Normally, the walls of the carotid and vertebral arteries have a smooth contour along their external and luminal surfaces and are uniform in thickness, measuring 1–2 mm (49). Your lymph nodes, also called lymph glands, play a vital role in your body's ability to fight off infections. Axial contrast-enhanced CT image shows enlarged palatine tonsils (arrows) that are in contact with each other (“kissing” tonsils) at the midline. (c) Coronal contrast-enhanced CT image at the level of the parotid glands in a 22-year-old woman with acute left parotiditis shows edema, enlargement, and hyperenhancement of the left parotid gland (white arrowhead). At the tooth apex, there is a periapical lucency and dehiscence of the bone plate (arrowhead) between the tooth and the maxillary sinus. Purpose: To assess the role of single-photon emission computed tomography with computed tomography (SPECT-CT) for the identification of sentinel lymph nodes (SLNs) in patients with early stage (T1-T2) oral cancer and a clinically negative neck (cN0). Whole body. (c) Sagittal nonenhanced CT image (bone window) shows calcification (arrow) inferior to the anterior arch of C1, in the typical location for calcific tendinitis of the longus colli. Portions of the circle of Willis are typically included at CT examinations of the neck, and consequently, intracranial arterial abnormalities may be visualized.