Incidence and morphometry of bony projections on the cerebral aspect of the petromastoid part of temporal bone in adult human skulls

ABSTRACT

To find out the incidence, side, position and morphometry of bony projections on the cerebral aspect of the petromastoid part of the temporal bone of dry adult human Bangladeshi skulls. It is an observational study. The incidence, side and position of the bony projections on the cerebral aspect of petromastoid part of temporal bone was ascertained by observation. The size of the bony projection was measured by millimeter scale. Department of Anatomy, Rajshahi Medical College, Rajshahi, Bangladesh. Out of total 100 petromastoid part of temporal bone [50 human skulls] bony projection was present in 44 [44%] close to the upper part of the groove for the sigmoid sulcus. The bony projection was unilateral and bilateral in 12 [27.3%] and 32 [72.7%] cases respectively and the incidence was equal [50%] on both right and left side. The projections were small, medium and large size in 26 [59.1%], 15 [34.1%] and 3 [6.8%] cases respectively. Position of the superior petrosal sulcus was superior and inferior to the bony Projection in 34 [77.3%] and 6 [13.6%] cases. In 4 [9.1%] the sulcus was inconspicuous. For an extensive exposure of clivus and petrous regions and their associated neural and vascular structures the tentorium cerebelli has to be dissected. The bony projection is closely related to the attachment of tentorium cerebelli and to the superior petrosal and sigmoid sinus. Thus awareness about its incidence and nature is important for the neurosurgeon and neurootologist to avoid any neurological and vascular accident