FIGURE 181.1. An adult presenting with a left submandibular region mass. A: Ultrasound (US) showing a lobulated mass in the submandibular gland (SMG) (arrows) deep to the mylohyoid muscle without evidence of ductal dilatation. No stone in the duct could be demonstrated with certainty. The examination was somewhat limited by the anatomy of the mandible in a patient who was somewhat short necked and had a fairly substantial-sized mandible. B, C: Images from a contrast-enhanced computed tomography study showing the left SMG to be enlarged but not obviously enhancing (arrows) compared to the right (arrowhead). In (C), the cause of the glandular changes was a stone impacted in the distal submandibular duct (arrow) with perhaps some periductal inflammatory changes that are of low grade (arrowheads) compared to the normal appearance of the posterior sublingual space on the opposite side. (NOTE: This case illustrates how chronic sialoadenitis can mimic a mass lesion and to some extent points out limitations of US in evaluation of a mass in this region, although sometimes US can be definitive with regard to medical decision making.)

FIGURE 181.2. A patient with sialolithiasis and sialoadenitis. The patient presented with pain and tenderness in the submandibular region. A–C: Contrast-enhanced computed tomography study in (A) a stone impacted in the mid submandibular duct. In (B), the stone is seen to lie at the point where the main submandibular duct curves around the posterior edge of the mylohyoid muscle; proximal duct obstruction at that point is present (arrow). In (C), the submandibular gland is enlarged and enhancing abnormally compared to the normal opposite side, and its proximal intraglandular ductal system obviously is distended.

FIGURE 181.3. A patient with pain and tenderness in the right submandibular region. The contrast-enhanced computed tomography (CT) study shows this to be due to sialolithiasis and sialoadenitis. A: There is a stone impacted in the mid submandibular duct and a second stone impacted at the position where the duct crosses over the posterior edge of the mylohyoid muscle (arrow in B). C: A third stone is present in the more proximal ductal system at the point where the main duct branches into the even more proximal intraglandular ductal system (arrowhead), and there is dilatation of the branching ducts within the gland (arrow). (NOTE: This study indicates how CT imaging can be definitive with regard to the nature and extent of inflammatory submandibular gland disease, especially with regard to the presence and position of stones and the status of the gland itself. For the most part, imaging with CT has replaced sialography in the evaluation of such patients.

FIGURE 181.4. A patient with severe left submandibular region pain that could be due to an inflammatory process possibly of dental origin. Contrast-enhanced computed tomography was done. A: There is an intense cellulitis throughout the floor of the mouth along the mandible (arrowheads). B: Cellulitis is still noted (arrowheads) and seen to be due to inflammatory sialoadenitis related to obstruction by a stone. The study excluded a drainable fluid collection. The patient was treated with antibiotics, and the gland subsequently was removed. C: Enlargement and enhancement of the submandibular gland is obvious compared to the normal opposite side, and there is dilatation of the glandular ductal system (arrow) and reactive possibly early suppurative adenitis at level 2 (arrowhead).

FIGURE 181.5. A patient presenting with chronic vague pain in the region of the left submandibular gland. Contrast-enhanced computed tomography in (A) shows enlargement and slight increased enhancement of the left submandibular duct compared to the right (arrow). In (B), there is a tiny stone within the submandibular duct near the region of the punctum. The stone was removed, and the patient’s symptoms resolved.

FIGURE 181.6. The chronic effects of sialolithiasis are illustrated in this patient who had contrast-enhanced computed tomography because of chronic pain at the angle of the mandible. The etiology was uncertain. A: A large stone is impacted in one of the more common areas where the main submandibular duct curves over the posterior edge of the mylohyoid muscle (arrow). B: The stone is still present, and a second stone is impacted within the ductal system (arrow). This has led to atrophy of the right submandibular gland, being much smaller than the normal gland (arrowhead) and showing some low-grade enhancement. Involutional changes such as these may be a manifestation of atrophy in the entire gland.

FIGURE 181.7. A–D: Patient 1 presenting with acute submandibular region pain and swelling. It was uncertain whether this was due to dental disease or disease within the submandibular gland (SMG). Contrast-enhanced computed tomography (CT) in (A) and (B) show marked enhancement of the SMG (arrows) and very extensive edema around the gland (arrowheads). In the axial section in (C) and coronal reformations in (D), there are glandular parenchymal changes and intense surrounding edema due to acute pyogenic infectious sialoadenitis. (NOTE: The patient’s symptoms resolved on antibiotics.) E–G: Patient 2 presenting with chronic pain and tenderness in the right submandibular region of uncertain etiology. Contrast-enhanced CT study in (A) shows low-grade enhancement and an obviously swollen right SMG without ductal dilatation or stones. The same findings are present in the remainder of the glands and along the sublingual space and floor of the mouth, as seen in (F) and (G).

FIGURE 181.8. Three patients and three different imaging techniques to evaluate ductal pathology. A–E: Patient 1. A study to demonstrate the appearance of inflamed obstructed submandibular ducts. This patient had a very small cancer of the anterior floor of the mouth not visible on computed tomography (CT) and covering the puncta of both submandibular ducts. In (A), this results in dilatation of both main submandibular ducts (arrows) and some enhancements along the ductal systems, which secondarily affects the sublingual glands. In (B), the enhancement of the sublingual glandular tissue and periductal soft tissues is very extensive. In (C) through (E), the dilatation of the ductal system within both glands and abnormal enhancement of both glands reflects the bilateral obstructive sialoadenitis. F–H: Magnetic resonance (MR) sialography in Patient 2 to demonstrate the appearance of dilated ductal systems as seen on that examination. Steady state images were used to reconstruct those images seen in (F) through (H). In (F), an oblique sagittal plane shows the main submandibular duct from its punctum (arrow) to its area of entry into the submandibular duct as it crosses over the posterior edge of the mylohyoid muscle (arrowhead). The sagittal image in (G) shows the branch point of the main parotid duct into the ramifying ductal system within the gland (arrowheads). A coronal reformation in (H) shows the bilateral dilated ductal systems (arrowheads). (NOTE: While this so-called technique of MR sialography is capable of producing images of the dilated ductal system, it provides relatively limited detail of the ducts. MR in general will not be as satisfactory as CT for the demonstration of stones or the evaluation of structures in and around the submandibular space (SMS) that might be other sources of pathology that mimics SMS-origin pathology.) I: Patient 3. A sialogram showing relatively subtle changes in the ducts ramifying within the substance of the submandibular gland manifest by some degree of cutoff of the ductal system (arrow) and areas of structuring, narrowing, and irregularity (arrowheads). Such detail is not possible with MR sialography.