ABSTRACT
Introduction: Anterior sylvian point (ASyP) had a constant relationship with a point in the skull just posterior to the “H”-shapedpterion over the squamous suture called the anterior squamous point (ASqP).Objectives: The objectives of this study were as follows: (1) To confirm and establish the cisternal nature of ASyP and itsrelationship to other important neural and sulcal structures along the sylvian fissure. (2) To confirm the relationship of theAntSyP (ASyP) with the external cranial landmark ASqP for surface mapping of frontal horn for emergency ventricular tapping.Materials and Methods: Forty adult human brains (20 – right side and 20 – left side), both male and female, were observedduring surgery in Government Theni Medical College. Reliability of frontal horn tapping using the apex of Paine’s trianglefrom ASyP as the entry point was analyzed using the following steps. Exposure of pterion by the standard FTP trauma flapincision. Standard FTP craniotomy opening of the skull and dura mater and observing for ASyP relation to ASqP. A catheterwas introduced through the apex of the Paine’s triangle identified using the surgical tapes to form a 2.5 cm isosceles trianglefrom the ASyP. A study of the relationship of ASyP to the external cranial surface, middle cerebral artery (MCA) bifurcation,and frontal horn of ventricles was done.Conclusion: It could be safely concluded that ASqP is a reliable external cranial landmark for ASyP. ASyP can be the referencepoint for Paine’s triangle and hence Paine’s point. Hence, Paine’s point could be used to tap the frontal horn in emergentsituations. Furthermore, MCA bifurcation can be reached by ASyP cisternal dissection.
ABSTRACT
Introduction: Language areas of brain show a beautiful anatomico-functional correlation. It has been often assumed that the interhemispheric asymmetry of Sylvian fissure and perisylvian cortex is the basis of hemispheric dominance for language.The lateral sulcus is one of the earliest-developing sulci of the human brain. Materials And Methods: 60 formalin fixed cadaveric brains irrespective of sexes were studied in the department of Anatomy. The total length of sylvian fissure on the superolateral surface till the posterior sylvian point was noted bilaterally. Among the other measurements taken were the lengths of anterior ascending, anterior horizontal and posterior limb of lateral sulcus till posterior sylvian point on the right and left cerebral hemispheres. Observation and Results: The mean of the total length of the lateral sulcus on the left side is 8.48 which is larger than the right side which is 8.39.The mean of the anterior horizontal rami on right side (1.97) is greater than left side (1.96). On the other hand the mean value of left anterior ascending ramus 2.41 is greater than the mean value of right anterior ascending ramus 2.37. The mean value of posterior limb of sylvian sulcus is also greater on the left side i.e. 6.43 than on the right side i.e.6.23.All measurements are in cms. Conclusion: The Sylvian fissure in this study is longer on the left side than the right which has been proved in previous studies.To correlate this structural asymmetry with the functional localization of speech and language calls for further studies.