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Dorsum of nose

The dorsum of the nose is the bridge-like, central part of the external nose, extending from the nasal root (nasion) superiorly to the tip (apex) inferiorly. Structurally, it is formed by the paired nasal bones, the upper lateral cartilages, and the overlying soft tissues, including skin, subcutaneous fat, and fibromuscular layers. Accurate knowledge of its normal imaging appearance on MRI and CT is essential for differentiating physiological anatomy from trauma, infection, neoplasms, or congenital deformities.

MRI Appearance of the Dorsum of Nose

T2-Weighted Images:

  • Cartilaginous structures (upper lateral cartilages) appear intermediate to high signal intensity.

  • Nasal bones display low signal (dark) due to dense cortical bone.

  • Overlying skin and soft tissue: intermediate signal.

  • Subcutaneous fat: hyperintense (bright).

  • Septal cartilage (if included): intermediate to high signal.

T1-Weighted Images:

  • Cartilage: intermediate signal (less intense than fat, higher than muscle).

  • Nasal bones: very low signal (dark/black).

  • Subcutaneous fat: hyperintense (bright).

  • Skin and fibromuscular layer: intermediate signal.

  • No intrinsic contrast in cartilage, but fat is clearly defined.

STIR (Short Tau Inversion Recovery):

  • Useful for highlighting edema or inflammation.

  • Cartilage: low to intermediate signal.

  • Fluid/edema (if present): markedly hyperintense (bright white).

  • Fat: suppressed, appears dark.

  • Normal dorsum with no pathology: mostly low signal except for cartilage.

CT Appearance of the Dorsum of Nose

• Bone window:

  • Nasal bones: hyperdense (bright white, well-defined edges).

  • Upper lateral cartilages: soft tissue density, less well-delineated than bone.

  • Overlying skin and subcutaneous tissue: soft tissue density.

  • Good for identifying fractures or bony abnormalities.

MRI images

Dorsum of Nose mri axial image -img-00000-00000