Related Experiment Video
Updated: Jun 17, 2026

Extracting the Cochlea from a Human Temporal Bone: A Cadaveric Protocol
Published on: August 18, 2023
The histologic relationship of preauricular sinuses to auricular cartilage
Brian Dunham1, Martha Guttenberg, Wynne Morrison
1Division of Pediatric Otolaryngology, The Children's Hospital of Philadelphia, 34th Street and Civic Center Boulevard, Philadelphia, PA 19104, USA. dunhamb@email.chop.edu
Objective:
To determine the histologic relationship and distance between excised preauricular epithelial sinus tract and the adjacent auricular cartilage (sinocartilaginous distance) in a series of patients. The excision of preauricular sinuses is a common surgical procedure. Recurrences are frequent and can be technically challenging. While advocated by several authors, the surgical removal of adjacent auricular cartilage is not universally performed.
Design:
Retrospective case series.
Setting:
Children's Hospital of Philadelphia.
Patients:
Fifty-two pediatric patients who underwent surgical excision of preauricular sinus tracts and adjacent auricular cartilage.
Interventions:
Between September 1, 2005, and July 31, 2007, the preauricular sinus tracts and adjacent auricular cartilage were excised from 52 pediatric patients. A pathologist reviewed a total of 58 specimens to determine the relationship between epithelial tract and cartilage.
Main Outcome Measure:
The sinocartilaginous distance in microns.
Results:
Patient ages ranged from 8 months to 17 years (mean age, 4 years). In all but 1 case, the tracts were in close proximity to the cartilage. The average sinocartilaginous distance was 472 mum (median distance, 400 mum); the 25th percentile was 250 mum. In over 50% of the specimens, the sinocartilaginous distance was less than 0.5 mm, and in nearly all of the these, the epithelial tract was in continuity with stromal tissue histologically indistinguishable from perichondrium.
Conclusions:
The observed sinocartilaginous distances suggest that it may be difficult to dissect most sinus tracts from the cartilage. The routine removal of a small portion of auricular cartilage along with the sinus tract may yield a more thorough excision and help to prevent recurrence.
Related Concept Videos
Anatomy of the Ear
The Auditory Ossicles
The aptly named stapes look very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in...
Cranial Bones: Lateral View
The temporal bone forms the lower lateral side of the skull. The temporal bone is subdivided into several regions. The flattened upper portion is the squamous portion of the temporal bone. Below this area and projecting anteriorly is the zygomatic process of the temporal bone, which forms the posterior portion of the zygomatic arch. Posteriorly is the mastoid portion of the temporal bone. Projecting...
Nose and Nasal Cavity
The Cochlea
Auditory Pathway
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
