A characteristic feature of these channels is a distinct lack of smooth muscle and elastic fibers found in normal blood vessels, which contributes to the tumor's hemorrhagic propensity after even minimal manipulation.7] From the posterolateral wall of the roof of the nasal cavity, the tumor may extend by one of several welldefined routes. The tumor may extend superiorly and gain access into the intracranial fossae though the roof of the infratemporal fossa or through the superior orbital fissure.3] With further progression, the tumor may be found lateral to the cavernous sinus and anterolateral to the internal carotid artery adjacent to Meckel's cave. Spread through the superior orbital fissure into the cavernous sinus may cause proptosis and signs of superior orbital fissure syndrome20 Less commonly, the tumor may extend through the roof of the sphenoid sinus and occupy a position medial to the internal carotid artery and lateral to the pituitary gland.78 Direct extension along the horizontal lamina of the ethmoids and the cribriform plate into the anterior cranial fossa is rare.78 IIC Or posterior to pterygoidplates Erosion of skull base; minimal intracranial Erosion of skull base; extensive intracranial with/without cavernous sinus ilIA IIIB Occasionally, a combined anterior and lateral approach is required for tumors with significant extension to infratemporal fossa, middle cranial fossa, or cavernous sinus.24 This approach also allows for early control of the internal maxillary artery, minimizing operative blood loss. Tumors that extend through the sella and insinuate between the pituitary medially and internal carotid laterally, however, are especially hazardous and difficult to manage surgically. These tumors are best managed by a combination of surgery and radiotherapy or external beam radiotherapy alone. Complications of surgery include life-threatening hemorrhage, optic neurovascular and cranial nerve injury, and meningitis.16.24. The most feared complication of radiation is the risk of secondary malignancy in the young patient.'8,SS Radiation may also affect the growth centers of the face, leading to abnormal development of the craniofacial skeleton, cause visual complications like cataracts, or result in optic atrophy and radiation osteoradionecrosis.18

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