Type of Article:  Original

Volume 7; Issue 2.1 (April 2019)

Page No.: 6456-6461

DOI: https://dx.doi.org/10.16965/ijar.2019.143


Dhinesh Kumar T *1, Tara Sankar Roy 2, Tony George Jacob 3, Charanjeet Kaur 4, Dinesh Kumar V 5.

*1 Assistant Professor, Department of Anatomy,  Academic block, Dhanalakshmi Srinivasan Medical College & Hospital, Siruvachur, Perambalur District, Tamil Nadu, India.

2 Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India.

3 Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India.

4 Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India.

5 Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, India.

Address for Correspondence: Dr Dhinesh Kumar, Assistant Professor, Department of Anatomy,  Academic block, Dhanalakshmi Srinivasan Medical College&Hospital, Siruvachur, Perambalur District, Tamil Nadu -621113, E-mail: drdhineshkumar@gmail.com


Background: Cochlear nerve serves as one of the nodal point for enabling the passage of sound in both directions. The knowledge of age related morphological changes in human cochlear nerve is important to understand its role in the manifestation of sensori-neural presbycusis.

Materials and Methods: The study was conducted in 21 human cochlear nerve samples, collected in 3 different age groups (0-30 years, 31-50 years, 51 years and above). Resin embedding of cochlear nerves was done. Semi-thin (1 µm) cross sections of the nerves were cut by glass knife on Reichert Ultra-microtome. Under light microscope, toluidine blue stained nerve sections were studied for shape, organization of connective tissue and number of fascicles.

Results: Cochlear nerve was comma-shaped across all the age groups studied. Majority of the nerve sections had a blunt round head and sharp tail. Few sections had blunt tail also. Nerve fascicles were well defined in all the 21 samples studied. The approximate number of fascicles across the various age groups varied from 60 to 85 per nerve. Numerous Schwann cells and numerous small sized blood vessels were found in the endoneurium of older age group compared to younger and middle aged groups.

Conclusion: However, we didn’t observe major qualitative changes across different age groups, but the present study provides novel baseline morphological data on the human cochlear nerve.

KEY WORDS: Cochlear Nerve, Morphology, Shape, Number of fascicles, Connective tissue organization.


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Cite this article: Dhinesh Kumar T, Tara Sankar Roy, Tony George Jacob, Charanjeet Kaur, Dinesh Kumar V. ANALYZING THE AGE RELATED CHANGES IN THE HUMAN COCHLEAR NERVE: A QUALITATIVE MICROSCOPIC STUDY. Int J Anat Res 2019;7(2.1):6456-6461. DOI: 10.16965/ijar.2019.143