Morphological and morphometric study of the vermian fossa (middle cerebellar fossa of Verga) in South Indian human adult skulls

objectives To find the incidence of vermian fossa in South Indian population and to measure the width and length of these fossae. Also we aimed to classify them according to the shapes. Methods The study included 20 cranial base (vault removed) and 15 occipital bones. These specimens belonged to the neuroanatomy laboratory of Kasturba Medical College, Mangalore, India. The inner aspect of the posterior cranial fossa was examined for the presence of the vermian fossa. The fossae were classified macroscopically (Kale et al, 2008) as triangular shape (type 1) and quadrangular shapes (type 2). The fossae which were other than these shapes were included under atypical type (type 3). Finally the length and width of these foramina were calculated with a digital vernier caliper. Results The vermian fossa was observed in 25 specimens (71.4%). It was triangular shaped (type 1) in 19 specimens (54.3%) and quadrangular (type 2) in 2 (5.7%). In 4 (11.4%) specimens it was having unusual morphology and considered as atypical (type 3). The mean length and width of the fossa was 13.6 ± 4.4 mms and 11.9 ± 3.3 mms respectively. Conclusions The details about the vermian fossa are scarce in the literature. The present study recorded the incidence rate of 71.4% in South Indian population. It was triangular in shape in majority of the specimens. We believe that the data obtained in the present study is of importance in neurosurgical literature. The findings may give an idea about the inferior cerebellar vermis of the brain. The study is also enlightening for the neuro anatomists and morphologists.