Occult spontaneous lateral intrasphenoidal encephalocele: A rare presentation
A 37-year-old male patient presented with complaints of transient loss of consciousness and persistent headache after minor head injury. He had no past history of head injury or brain surgery. Neurological examination was normal and there was no stigma of neurofibromatosis. Plain CT head did not show any brain parenchymal or bony injury. Contrast-enhanced 3-mm axial and coronal CT images of paranasal sinuses [Figure and ] revealed a large (approximately 12 mm in size) defect in the right lateral wall of the sphenoid sinus with herniation of a part of the right mesial temporal lobe through the defect, to occupy the ipsilateral lateral recess of the sphenoid sinus. The remaining part of the right sphenoid sinus showed mucosal thickening. The bones around the defect and encephalocele showed remodeling and appeared thinned out [Figure and ]. There was no evidence of meningitis or any other intracranial abnormality. CT cisternography was not performed as there was no history of nasal discharge. Further evaluation of the lesion with MRI was not possible because the patient was claustrophobic and refused to undergo sedation.\nThe surgical exploration confirmed the CT finding of a large bony defect in the right lateral wall of the sphenoid sinus, lateral intrasphenoidal encephalocele occupying the lateral recess with otherwise intact dura. Mild ipsilateral sphenoid sinus mucosal thickening was also documented. Endoscopic transpterygoid approach was used and the herniated brain tissue with intact dura was gently pulled up and the bony defect was closed to prevent future risk of CSF leak, ascending meningitis or brain abscess. The abnormal mucosal thickening was stripped off and space within the right sphenoid sinus was filled with free fat graft. The patient had a good postoperative recovery and was advised cross-sectional follow-up study after six months to confirm the integrity of the repair.