A study on the insertion characteristics of rectus muscles and its relation with the axial length of eye ball in cadaveric eyes from an eastern Indian population

Abstract

The primary aim was to record measurements of relevant anatomy of recti muscle insertions in relation to limbus and with each other, and also to find whether these measurements vary with the axial length of the eyeball in an eastern Indian perspective. Eye balls ( n= 64, 20 female and 44 male) from Institutional eye bank were examined, within eight hours of death of the donor, under operating microscope by a single observer between May 2009 to April 2010.The mean distance from limbus to each rectus muscle at midpoint and at each end of insertion was measured by Castroviejo caliper. Additional parameters studied were length of each rectus muscle insertion (‘width’), distance between each rectus muscle insertion and measurement of axial length using 10 MHz ultrasonic A scan probe. Data collected was entered in Microsoft Office Excel 2007 and analysed by using statistical software SPSS 10. The frequency was calculated in percentages. Criteria for significance used in the study was at p<0.05. The mean age of the donors was 71years with a range of 26-86 years. Statistically significant difference (p<0.05) was found between male and female eyes regarding distance of limbus to midpoint point of only medial rectus muscle insertion. No statistically significant (p>0.05) difference was found between male and female eyes regarding length of line of rectus muscles insertion. No statistically significant correlation (p>0.05) was observed between the axial length and various measurements of rectus muscle insertion. Results of this study might help local strabismologists in revaluation of the spiral of Tilluax based on regional (Eastern Indian) perspective.

Key words: Eye ball; Rectus muscles; Rectus muscle insertion; Axial length; Indian population.