Para-parotid Gland (Transverse Scan)

Para-parotid Region — Transverse Scan (Ultrasound): The para-parotid region refers to the soft tissues immediately adjacent to the parotid gland (parotid tail, superficial fat planes, masseteric and buccal spaces, intraparotid and peri-parotid lymph nodes and adjacent fascia). A transverse (short-axis) ultrasound scan is used to assess cross-sectional anatomy, detect focal lesions that abut the gland, and evaluate lymphadenopathy or inflammatory collections in the para-parotid soft tissues.Anatomical Landmarks: On transverse scanning the key external landmarks are the zygomatic arch superiorly, the angle of the mandible inferiorly, the preauricular skin crease laterally, and the masseter muscle and mandibular ramus medially. Internally, look for the parotid parenchyma, Stensen’s duct as it crosses the masseter, superficial fascial planes, and adjacent lymph nodes.

Scanning Method: Para-parotid gland usually lies between anterior border of the main parotid gland and the masseter muscle. Probe Placement & Sweep (Transverse Technique): Place the transducer perpendicular to the long axis of the gland (short axis) across the preauricular region. Orient the probe so the image shows lateral (skin) to medial (mandible/masseter) structures. Sweep superior → inferior and anterior → posterior to include the full para-parotid space, tail of parotid, and superficial lymph node stations. Repeat the transverse sweep while angling slightly cephalad/caudad to interrogate hidden pockets or ductal segments.

Section Structure or What to Evaluate: On the transverse section, the normal para- parotid gland is a thin solid area which has a well circumference and with the same echogenic feature with the main parotid parenchyma. There is a very thin connection between the para and main parotid gland.

1. APG- Anterior parottid gland
2. PG- Parotid gland
On transverse views assess: contour and echotexture of the parotid and para-parotid fat, presence of focal masses or cysts adjacent to the gland, enlarged or abnormal lymph nodes (shape, hilum, cortical thickness), ductal dilatation, focal fluid collections/abscesses with internal echoes, and relationship of lesions to the mandible and masseter. Use color Doppler to evaluate internal vascularity (helps differentiate inflammatory vs cystic vs neoplastic processes).

Measurement mathod: Measure maximal transverse diameter of any lesion, record its depth from skin, note echotexture, presence/absence of internal vascularity (color/power), and relation to parotid gland and mandible. Compare with the contralateral side and document probe frequency, patient position, and Doppler settings used.

Notes:The connection of the para and main parotid glands shown during continuous ultrasound scan is the key point to avoid misdiagnosing the para- parotid gland as a solid neoplasm.

Normal Sonographic Appearance: Para-parotid soft tissue normally shows thin hyperechoic subcutaneous fat and anechoic/heterogeneous connective planes. Small intraparotid or peri-parotid lymph nodes (oval with echogenic hilum) may be seen. No abnormal focal mass, fluid collection, or asymmetric vascularity should be present.
Anatomimical appearance

Sonographic appearance

Common Pathologic Findings — Para-parotid Gland / Region:

• Lymphadenopathy — Most frequent finding; enlarged oval/round nodes. Reactive nodes show preserved fatty hilum and hilar vascularity, whereas suspicious nodes show loss of hilum, round shape, peripheral or chaotic vascularity.

• Abscess / Phlegmon — Irregular hypoechoic or complex collection with internal echoes and peripheral vascularity; may extend from dental, skin, or parotid infection.

• Cystic Lesions — Congenital (branchial cleft cyst) or acquired (infected cyst, lymphoepithelial cyst). Anechoic with posterior enhancement; may have internal debris if complicated.

• Benign Tumors — Lipoma (hyperechoic, compressible, no Doppler flow), Fibroma, or hemangioma. Usually well-circumscribed.

• Malignant Infiltration — Extension of parotid carcinoma, lymphoma, or metastatic nodes; appears as irregular, heterogeneous hypoechoic mass infiltrating fat planes.

• Vascular Anomalies — Prominent external carotid branches or venous malformations; tubular/serpiginous channels with flow on Doppler.

• Post-treatment Changes — Fibrosis, scarring, or necrotic nodes after radiotherapy or surgery.

Reporting: A concise report should state side examined, probe frequency, normal/abnormal findings of the para-parotid soft tissues, size and description of any focal lesion, Doppler vascularity, suggestion of likely diagnosis (e.g., reactive node, abscess, cyst, neoplasm), and recommendation for further imaging or FNAC/biopsy if indicated.