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Published on: January 11, 2018
Evaluation of the human petrotympanic fissure using anatomized cadaveric specimens and multi-detector CT imaging
Óscar Villalba1, Santiago Rojas2,3, Marisa Ortega2,4
1Clinic and Dental Center Empuriabrava, Empuriabrava, Spain.
Purpose:
The purpose of the current study is twofold. First, to investigate the variability of the petrotympanic fissure's (PTF) morphology in anatomized human cadaveric specimens using multi-detector computed tomography (MDCT), and second, to compare the resulting measurements to investigate the possibilities of applying MDCT in the determination of PTF morphology in living humans.
Methods:
Specimens (n = 15) containing the temporal bone and TMJ were obtained from embalmed adult female (53.3%) and male (46.7%) cadavers and imaged using a helical 16-row scanner. Afterwards, cryosections were obtained and morphometric parameters were measured. Degree of agreement between both determinations was investigated and morphometric variables were also compared between PTF types.
Results:
Three different types of PTF were identified. Type 1 was a wide tunnel-shaped structure. It was found in 20% of the cases. Type 2 was wide in the entrance but gradually narrows to the tympanic cavity. It was found in 46.7% of specimens. Finally, type 3, which was observed in 33.3% of the cases, was wide at the entrance of the mandibular fossa, followed by a middle region with flat-shaped tunnel structure and a narrow exit. The PTF's vertical diameters at the mandibular fossa, midpoint, and tympanic cavity and the width at the mandibular fossa all were significantly greater in type 1 specimens.
Conclusions:
MDCT is suitable for investigating the variable morphology of human PTF and its association with middle ear's and TMJ pathologies.
