Preauricular Lymph Node
A preauricular lymph node is a small immune gland located just in front of the ear. These lymph nodes help filter lymph fluid and fight infection, especially in areas involving the face, scalp, and outer ear. When a radiology report mentions a preauricular lymph node, it means imaging has shown a visible node in this location. Sometimes it’s normal, but other times it may reflect an infection, inflammation, or more rarely, a tumor. Understanding what this finding means can help you discuss it with your doctor.
Where the Preauricular Lymph Node Is Located
The preauricular lymph node sits in front of the tragus, the small cartilage bump at the front of your ear canal. It is part of the facial and head lymphatic drainage system. Lymph fluid from the forehead, scalp, eyelids, cheek, and outer ear often flows into these nodes.
On imaging, the preauricular lymph node appears as a small, oval structure with soft-tissue density. Depending on the imaging method, it may be clearly visible or only show up when enlarged.
When Preauricular Lymph Nodes Show Up on Imaging
Radiology studies that may show preauricular lymph nodes include:
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Ultrasound – Used for superficial swellings or lumps near the ear. It can show the node’s size, shape, and internal structure.
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CT Scan – Can detect both normal and abnormal lymph nodes, especially when assessing head and neck conditions.
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MRI – Offers detailed soft tissue contrast for evaluating surrounding structures.
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PET/CT – Used in cancer evaluation to check for spread to lymph nodes.
In many cases, these nodes are not visible unless they are swollen, but modern high-resolution imaging can detect even small, normal-sized nodes.
Common Reasons for Enlarged Preauricular Lymph Nodes
The preauricular lymph node can become enlarged for several reasons:
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Infections
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Eye infections such as conjunctivitis (especially viral, like adenovirus)
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Skin infections of the scalp or face
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Ear infections affecting the outer ear
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Inflammatory conditions
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Autoimmune disorders
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Allergic skin reactions
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Tumors
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Skin cancers of the scalp, temple, or eyelid
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Salivary gland tumors near the ear
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Spread from other head and neck cancers
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Systemic illnesses
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Viral illnesses like mononucleosis
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Certain bacterial infections such as tuberculosis
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How Radiologists Evaluate Preauricular Lymph Nodes
When reading a scan, radiologists assess several features to determine if a preauricular lymph node looks normal or abnormal:
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Size – Normal lymph nodes in this region are often under 1 centimeter in short-axis diameter.
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Shape – Healthy lymph nodes tend to be oval; rounder nodes may raise suspicion.
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Hilum visibility – The fatty center (hilum) is often visible in normal nodes on ultrasound; loss of the hilum can suggest disease.
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Margins – Smooth borders are usually benign; irregular or spiculated edges can be concerning.
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Internal structure – Cystic areas, calcifications, or abnormal vascularity may require further work-up.
When Additional Testing Is Needed
If imaging shows an abnormal preauricular lymph node, your doctor may recommend further evaluation:
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Follow-up imaging – To see if the node changes in size over time
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Ultrasound-guided fine needle aspiration (FNA) – A small sample is taken for lab analysis
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Blood tests – To check for infection or systemic illness
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Full head and neck exam – To find possible sources of infection or tumor
What Patients Should Know
A mention of a preauricular lymph node on a radiology report is not automatically a sign of something serious. Many times, the finding is related to minor infections that resolve on their own. However, persistence, rapid growth, or unusual imaging features can signal the need for more investigation.
Patients should tell their doctor about:
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Any recent ear, eye, or scalp symptoms
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Skin lesions on the head or face
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Past history of cancer or immune disorders
Imaging Appearance in Different Conditions
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Benign reactive lymph nodes
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Small, oval, well-defined
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Preserved fatty hilum
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Appear on ultrasound as homogeneous with normal blood flow
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Malignant lymph nodes
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Larger than expected for the region
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Round shape, irregular borders
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Loss of fatty hilum, heterogeneous texture
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May show abnormal blood vessel patterns on Doppler ultrasound
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Infected lymph nodes (lymphadenitis)
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Enlarged, tender
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Surrounding fat stranding on CT
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May have central low-density areas suggesting pus (abscess formation)
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Role of the Radiology Report
A radiology report mentioning a preauricular lymph node often includes:
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Location and side (right or left)
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Size in millimeters
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Imaging features (shape, internal architecture, border)
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Impression of benign vs suspicious features
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Recommendations for follow-up or biopsy if indicated
This language helps the referring physician decide on the next step, whether that’s reassurance, observation, or further work-up.
Why Early Detection Matters
For infection-related swelling, early diagnosis means earlier treatment and faster recovery. For cancer-related changes, identifying suspicious lymph nodes can be important for staging, prognosis, and planning surgery or radiation.
Radiologists play an important role in catching these changes before they cause symptoms, especially when the lymph node enlargement is subtle and only visible on imaging.
Bottom Line
A preauricular lymph node on a radiology report simply means a lymph node in front of your ear has been seen on imaging. Most of the time, this is a normal or reactive finding due to infection or inflammation. In some cases, further tests are needed to rule out more serious causes. If your report mentions this finding, talk to your doctor, especially if you have persistent swelling, tenderness, or skin changes in the nearby areas. Imaging helps guide whether the node needs monitoring, more testing, or no further action.
References
https://radiologyassistant.nl/head-neck/cervical-node-mapping/cervical-node-map
https://www.verywellhealth.com/preauricular-lymph-nodes-8638158
https://nobleresearch.org/Doi/10.14312/2399-8172.2016-3