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IJAR.2019.341

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Type of Article:  Original Research

Volume 8; Issue 1.1 (January 2020)

Page No.: 7212-7216

DOI: https://dx.doi.org/10.16965/ijar.2019.341

EVANS’ INDEX IN HEALTHY NORTH INDIAN POPULATION: A COMPUTED TOMOGRAPHIC STUDY

Lohani M 1, Sehgal G *2, Pasricha N 3, Stapak E 4, Mishra SK 5.

1 Assistant Professor, Department of Anatomy, Prasad Institute of Medical Sciences, Lucknow, India.

*2 Associate Professor, Department of Anatomy, King George’s Medical University, U.P., Lucknow, India.

3 Associate Professor, Department of Anatomy, Dr Ram Manohar Lohia Institute of Medical   Sciences, Lucknow, India.

4 Assistant Professor, Department of Anatomy, Dr Ram Manohar Lohia Institute of Medical Sciences, Lucknow, India.

5 Consultant & Head, Department of Anaesthesia, Charak Hospital &Research Centre, Dubagga, Lucknow, India.

Corresponding Author: Dr. Garima Sehgal, Associate Professor, Department of Anatomy, King George’s Medical university, U.P., Lucknow- 226003, India. Mobile: 9044513758   E-Mail: drgarimabhasin@gmail.com

ABSTRACT

Background: As the humans age, there is decrease in size of brain tissue, increase in cerebrospinal fluid volume and enlargement of ventricles. Brain ventricles can be studied by taking linear, planimetric or volumetric measurements. Linear ratios of width of ventricles to the width of skull or brain are considered to be an easy and reproducible measurement for assessment of ventricles. Evans’ index is one such linear ratio; it is the ratio of maximum width of frontal horns and maximum transverse internal diameter of skull in the same plane.

Purpose of study: The purpose of our study was to obtain a baseline data of reference values of Evans index, in healthy north Indian population.

Materials and Methods: This study was jointly conducted by Department of Anatomy and Department of Radiodiagnosis, King George’s Medical University, U.P, Lucknow. Axial CT scans of head region reported radiologically normal, belonging to 100 individuals of different age groups were retrospectively collected and thoroughly analyzed using Radiant DICOM Viewer Software. Study subjects were categorized into V groups as per age: 18-30years, 31-40years, 41-50years, 51-60years and above 60years. Evans’ index was calculated.

Results: Among study subjects, Evans’index ranged from 0.167 to 0.29 with a mean value of 0.23±0.02. No significant association was observed between age and mean Evans’ Index (p>0.05). Mean Evans’ index was equal for male and female and was not found to change with age.

Conclusion: Study provided values for normal range of Evans’ index and proposes age dependent values of the same for healthy adult males and females. The data could be utilized in routine radiological practice and by others where required.

Key words: Evans’index, Ventricles, CT scan, Linear ratio, Brain.

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Cite this article: Lohani M, Sehgal G, Pasricha N, Stapak E, Mishra SK. EVANS’ INDEX IN HEALTHY NORTH INDIAN POPULATION: A COMPUTED TOMOGRAPHIC STUDY. Int J Anat Res 2020;8(1.1):7212-7216. DOI: 10.16965/ijar.2019.341