Neuronal Quantification of Subthalamic Nucleus in Adult Human Cadaveric Brain- A Histological Study

Abstract

Introduction: The Subthalamic Nucleus (STN) has emerged as a preferred target site for deep brain stimulation for various neurological disorders. There is scarcity of literature on the internal structure of subthalamic nucleus. Aim: To study its microanatomy and quantification of its various cells in different age groups. Materials and Methods: The study design of the current study is of cross-sectional type which was done on 30 cadaveric brains in Anatomy department of Lady Hardinge medical college, New Delhi which were divided into three age groups ranging from 20 to >50 years. The subthalamic nucleus was fixed and subjected to standard tissue processing procedure. The sections were stained with Haematoxylin and Eosin (H&E), Nissl and Haggqvist staining. The neurons and neuroglia were studied in 25 representative areas, measuring 75166 μm2 in each age group, using the upright binocular optical microscope and image analysis software. The number of neurons and neuroglia with their ratio was calculated and results were statistically analysed using Microsoft Excel software (2010 version). Results: Three types of neurons were identified as multipolar, fusiform and pear-shaped neurons. The ratio of neuroglia to neurons in the three age groups was calculated as: Group A-9.197, Group B-9.274 and Group C-10.478. A p-value of 0.04 was observed on comparing the neuronal and neuroglial density in Group A and C, demonstrating a significant increase in the density of neuroglia with age. Conclusion: The results obtained in the present study can provide prerequisite knowledge to anatomists, pathologists, and neurosurgeons for detection of various pathologies and interventional procedures, respectively.