The Morphometric Study for the Rolandic Fissure

Objective : The purpose of this study was to characterize the Rolandic fissure[Rf] and was to identify the Rf using the surface bony landmarks which can be usually exposed on craniotomy. Methods : After morphological evaluation of the Rfs using 21 Korean adult formalin fixed cadavers, craniometric measurement was carried out from the surface bony landmarks of nasion, glabella, bregma, and lambda. Results : The Rfs of both hemispheres did not show the mirror image. The Rfs ran forward and downward toward the sylvian fissure keeping the mean angle of $67^{\circ}$ from mid-sagittal line as elongated S-shape in left and the elongated reverse S-shape in right hemisphere. Connections between the Rf and the longitudinal fissure and between the Rf and the sylvian fissure were found in 3 [7.1%] and 2 [4.8%] of 42 hemispheres, respectively. Most Rfs extended superiorly to 2-3mm lateral to the most superomedial surface of hemispheres and extended inferiorly to 3-5mm superior to the sylvian fissures. The mean distances from the nasion, glabella, bregma, and lambda to the most superomedial aspect of the Rf were $18.8{\pm}0.9cm,\;16.6{\pm}0.8cm,\;5.2{\pm}0.6cm$, and $6.9{\pm}1.0cm$, respectively. The mean distance measured between the Rf and the nasion using traditional method was $18.4{\pm}0.6cm$. Conclusion : The distance between the Rf and the nasion roughly correspond within the range of mean 4 mm compared with that measured by the traditional measurement. These data may be more helpful to delineate the Rf after the placement of drapes for craniotomy.