Clinical features
- The classic presentation of CNH is a middle-aged to elderly man with a spontaneously appearing painful nodule on the helix or antihelix.
- The nodule usually enlarges rapidly to its maximum size and remains stable.
- Onset may be precipitated by pressure, trauma, or cold.
- When asked, the patient sometimes admits to sleeping on the affected side.
- Nodules are firm, tender, well demarcated, and round to oval with a raised, rolled edge and central ulcer or crust.
- Removal of the crust often reveals a small channel.
- Color is similar to that of the surrounding skin, although a thin rim of erythema may exist.
- Size may range from 3-20mm.
- Most common location is the apex of the helix and on the right ear.

Copyright : Mitsuhiro Sugiura, M.D.
Histological features
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- The histologic changes are similar to those seen in decubitus ulcers, but on a smaller scale.
- Within the central portion of a shave biopsy, the epidermis usually is ulcerated.
- At the periphery, intact epidermis is edematous and acanthotic.
- The dermis below the ulceration demonstrates homogeneous acellular collagen degeneration with fibrin deposition.
- Granulation tissue flanks the zone of necrosis on both sides.
- A focus of cartilaginous degeneration may be present, although it is usually minimal.
For additional information about chondrodermatitis nodularis helicis see: eMedicine
and PathConsult 