Page 120 - Atlas of Small Animal CT and MRI

Figure 1.8.5 Reactive Lymphadenopathy (Canine) CT

12y MC Labrador Retriever with cervical necrotizing cellulitis and septicemia. The pharyn-
geal soft tissues are thickened and fascial margins are poorly delineated as a result of
diffuse regional cellulitis (asterisks). Mandibular lymph nodes are variably enlarged and are
somewhat more spherical than normal (arrows). Contrast enhancement is uniform.
Low‐density foci in some nodes are attributable to fat within the lymph node hilus.
Microscopic evaluation of mandibular lymph nodes following euthanasia revealed marked
diffuse plasmacytosis and lymphocytosis, consistent with node reactivity.

(a) CT+C, TP

Figure 1.8.6 Pyogranulomatous Lymphadenopathy & Lymph Node Abscess (Canine) CT

(a) CT+C, TP (b) CT+C, TP
7y MC Weimaraner with recent‐onset difficulty swallowing and pain on manipulation of the head and neck. Representative contrast‐
enhanced CT images are at the level of the mandibular (a) and retropharyngeal (b) lymph nodes. Mandibular lymph nodes are enlarged
and have extensive nodal and ill‐defined perinodal contrast enhancement (a: arrows). Similar findings are seen associated with the medial
retropharyngeal lymph nodes (b: arrows). In addition, the left medial retropharyngeal lymph node is greatly enlarged and contains a fluid
component ventrally consistent with frank abscessation. Aspiration cytology from the medial retropharyngeal lymph node confirmed suppurative
inflammation and necrosis.

Figure 1.8.7 Regional Lymph Node Metastasis (Canine) CT

10mo F German Shepherd Dog with an
undifferentiated oral sarcoma, present since
8 weeks of age. The left mandibular lymph
node is markedly enlarged on the unenhanced
image (a). Following contrast administration,
there is peripheral enhancement of the man-
dibular lymph node with a central nonenhanc-
ing region representing metastasis (b: arrow).
Fine‐needle aspiration cytology confirmed
nodal metastasis.

(a) CT, TP (b) CT+C, TP
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