الفهرس 
List of ContentsOnly 14 pages are availabe for public view
 |  | from | 141 |  |  |
| | | from | 141 | | |
Abstract
The petrous apex is bounded by the bony labyrinth and internal carotid artery (ICA) anteriorly, the posterior cranial fossa and Dorello’s canal (cranial nerve VI) posteriorly, the middle cranial fossa and Meckel’s cave superiorly, and the jugular bulb and inferior petrosal sinus inferiorly. The petrous apex is infrequently involved by disease.
Although a proper diagnosis can often be made based on radiologic appearance alone, surgery may be necessary to establish a diagnosis or provide treatment. Expansile lesions of the petrous apex are most commonly diagnosed as cholesterol granulomas. The prevailing theory is that cholesterol granulomas are the result of obstructed air cells within the pneumatized spaces of the temporal bone.
The clinical symptoms of pathologic processes of the petrous apex are often vague but may include diplopia, hearing loss, vertigo, headaches, and facial nerve weakness. Hearing loss and vestibular abnormalities may present as the lesion enlarges and encroaches on the internal auditory canal.
The most common approaches to use in petrous apex lesions in a hearing ear include transcanal infracochlear, infralabyrinthine, suboccipital, and middle cranial fossa approaches. These procedures require advanced technological skill to decrease complications associated with intracranial procedures, such as sensorineural hearing loss, vestibular injury, facial nerve damage, cerebrospinal fluid leak, or meningitis.
Endoscopic endonasal approaches, fitting the concept of minimally invasive surgery, are currently considered among the strategies of surgical treatment for the management of several skull base tumors, including those extending to or involving the petrous apex. However, as a strict midline window, this path may be unable to properly manage neoplasms involving the most lateral aspects of the skull base.
In the current studywe aimed to compare the surgical freedom, area of exposure, and angle of attack of afforded by the endonasal transpterygoid with those of the infracochlear approach. enrolled 7 fresh frozen cadavers. Bilateral endonasal transpterygoid and infracochlear approaches were performed and measurements of surgical freedom, area of exposure, and angle of attack were calculated.
The study found that the results of these measurement in both approaches showed a wide range in all obtained measurements and no statistically significant differences were found between both approaches. The main explanation of these findings is that one approach does not fit every operation. There are a variety of factors to consider in choosing the best approach including anatomic limitations and location of the lesion within the petrous apex.