This diagnostic axial CT image of the head at the level of the nasopharynx illustrates the complex anatomy and compartmentalization of the parapharyngeal spaces, essential for staging nasopharyngeal carcinoma (NPC). The diagram uses color-coded overlays and lines to delineate anatomical boundaries formed by the three layers of the cervical fascia: the superficial layer (orange line), the middle layer (bright green line), and the deep layer (dark blue line). Key spaces identified include the masticator space (MS, blue), prestyloid space (PSS, purple), carotid space (CS, green), retropharyngeal space (RPS, pink), prevertebral space (PVS, yellow), and parotid space (PS, brown). Internal structures of the masticator space are labeled, including the medial pterygoid (MP), lateral pterygoid (LP), masseter (M), and temporalis (T) muscles. Crucially, a red outline distinguishes the 'staging masticator space,' which excludes the pterygoid muscles but includes the retromaxillary fat pad (RT), from the broader 'anatomic masticator space.' This illustration serves as a clinical guide for evaluating tumor extension and identifying structures involved in T-stage classification.

**Imaging Modality:** Magnetic Resonance Imaging (MRI), T1-weighted sequence.

This clinical diagnostic image is a high-definition endoscopic view of the right lateral nasopharynx in a healthy adult. The image clearly demonstrates the anatomical landmarks of the pharyngeal orifice of the Eustachian tube. Key structures labeled include the Eustachian tube opening appearing as a dark slit, the Rosenmüller fossa (pharyngeal recess) located posteriorly, and the torus tubarius. The muscular anatomy is delineated, showing the tensor veli palatini anteriorly and the levator veli palatini inferiorly. The salpingopharyngeus muscle is visible as a vertical fold of mucosa. Other landmarks include the soft palate forming the inferior boundary, the nasopharyngeal wall, and the posterior edge of the nasal septum. The mucosa appears healthy, pink, and well-vascularized without signs of inflammation, lymphoid hyperplasia, or obstruction. This image serves as a reference for normal nasopharyngeal anatomy and the study of peritubal muscle relationships relevant to Middle Ear Myoclonus (MEM) and Eustachian tube dysfunction.

This diagnostic image is an axial (transverse) Magnetic Resonance Imaging (MRI) scan of the human nasopharynx in a healthy subject. The view provides a detailed anatomical study of the upper airway and its surrounding mucosal landmarks. Centrally, the posterior aspect of the nasal septum is visible, exhibiting a slight lateral deviation. The nasopharyngeal lumen is clearly defined, showing key lateral and posterior wall structures. The Rosenmüller fossa (lateral pharyngeal recess) is identified as a deep indentation on the lateral wall, appearing with a heterogeneous signal intensity and ill-defined borders. Anterior to this fossa is the orifice of the Eustachian tube, visualized as a small opening with a dark signal. On the midline of the posterior wall, the pharyngeal bursa is depicted as a small, smooth-contoured protrusion. This imaging modality is essential for evaluating obstructive sleep apnea (OSA), nasopharyngeal carcinoma, or lymphoid hypertrophy, as it allows for precise assessment of spatial relationships and mucosal symmetry within the rhinopharynx.

This diagnostic endoscopic image captures the nasopharynx, demonstrating an extraosseous plasmacytoma in a 75-year-old male. The primary finding is a large, smooth, fleshy pink-to-red mass protruding into the nasopharyngeal space. The mass exhibits prominent surface vascularity with branching vessels and is shown effacing the posterior pharyngeal wall. Key anatomical landmarks are annotated, including the Eustachian tube opening and the Fossa of Rosenmuller located superior to the lesion. The mass is positioned adjacent to the posterior nasal septum and the posterior lateral nasal wall. This clinical photograph illustrates the typical presentation of a rare extramedullary plasma cell neoplasm in the upper respiratory tract, which may present with symptoms such as epistaxis. The image serves as an educational resource for Otolaryngology and Oncology, highlighting the importance of endoscopic examination in evaluating nasopharyngeal masses.