Accessory osseous passages in the vicinity of foramen rotundum in a dry adult human skull: morphological evaluation, embryological correlation and clinical reappraisal.

An unusual bony depression with accessory osseous passages in the right side of middle cranial fossa was observed in a dry adult human skull. It was located below the superior orbital fissure and optic canal. The bony depression was divided into two parts ,medial and lateral fossa, by an incomplete oblique bony septum. The foramen rotundum and an accessory bony canaliculus were present in the medial fossa whereas the lateral fossa was blind. The foramen rotundum led as usual into the pterygopalatine fossa . The presence of such an abnormal bony depression in the right middle cranial fossa with accessory osseous passages in the vicinity of the foramen rotundum is highlighted in the present case, with embryological correlation and clinical relevance. Anatomical awareness of such variations in the middle cranial fossa are important for the present day radiologist who interprets imaging for this area, neurosurgeons , who operate in this area in the vicinity of cavernous sinus and anaesthetists, during regional block anaesthesia.