Head and Neck ImagingSjogren's syndrome
(Henrik Samuel Conrad Sjogren, born 1899, Swedish ophthalmologist) systemic autoimmune disorder of exocrine glands, also called sicca syndrome. It primarily affects the salivary and lacrimal glands. It is seen most commonly in middle-aged women. The symptoms include enlarged salivary glands (mainly parotid glands), dry mouth (xerostomia) and dry eyes (causing keratoconjunctivitis sicca). It may present as recurrent acute episodes of
glandular swelling, or as a more chronic disease with progressive
glandular enlargement; forms with a mixed clinical picture can occur.
When only the exocrine glands are affected, the syndrome is called primary Sjogren's syndrome; it is referred to as secondary Sjogren's syndrome when associated with a connective tissue disease (most commonly
rheumatoid arthritis ).
The diagnosis is confirmed with a labial
biopsy, showing findings similar to those of a
benign lymphoepithelial lesion . Specific autoimmune antibodies have been identified (SS-A and SS-B antibodies), but are not always elevated, particularly in men with primary Sjogren's syndrome.
Patients with Sjogren's syndrome have an clearly increased risk of developing
non-Hodgkin lymphoma, head and neck manifestation , both within the
parotid gland as at extraparotidal sites.
A similar syndrome occurs in children, and is known as recurrent parotitis of childhood; these patients do not develop advanced parotid disease and the disease does not usually go on into adulthood.
Diagnostic imaging
Sialography is the most sensitive radiological method for demonstrating glandular changes in Sjogren's syndrome. Initially, punctate contrast collections are seen throughout the gland, with normal-appearing ducts. The uniform distribution of these small collections is specific for Sjogren's syndrome, and allows differentiation from other kinds of sialadenitis. Similar changes are observed in recurrent parotitis of childhood (Fig. 1). With progression of the disease, acinar destruction occurs with superimposed infection; this creates more globular contrast collections, and ductal dilatation and irregularities also appear (Fig. 2). Eventually, large peripheral collections are seen in the gland, associated with ductal dilatation and malformation.
The CT and MRI findings in Sjogren's syndrome are variable. Initially, the salivary glands appear normal.In early cases, punctate hyperintensities may be seen on T2-weighted MR images, corresponding to the very small collections visible on sialography (Fig. 3). Later, enlargement and more or less pronounced enhancement of the parenchyma is seen, resembling changes seen in patients with chronic sialadenitis ; fluid-filled cavities may be present (Fig. 4). In advanced cases, salivary gland abscesses occur.
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