الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Both spiral CT and MRI can not be used to detect and delineate superficial laryngeal carcinoma, which is usually detected by laryngoscope and confirmed by biopsy.
On the other hand both spiral CT and MRI are well helpful to detect the degree of tumor extension to the laryngeal spaces, invasion of the laryngeal cartilages and lymph nodes involvement which can not be detected by laryngoscope.
As regard of tumor spread to the laryngeal spaces, for spread to the pre-epiglottic space, it is found that the sensitivity of both spiral CT and MRI to detect invasion at this space are equal, while spiral CT is more specific than MRI.
For tumor spread to the paraglottic space, it is found that MRI is more sensitive than spiral CT to detect invasion of this space, while both of them have equal specificity, however this specificity is limited due to the fact that peritumoral inflammatory changes may lead to overestimation of tumor spread by both imaging methods.
For tumor spread to the subglottic space, it is found that MRI is more sensitive than sprial CT, while both of them have equal but limited specificity as both imaging methods can not distinguish between the tumor and peritumoral inflammatory changes, which may result in overestimation of the tumor.
Tumor invasion of laryngeal cartilage is important sign in tumor staging, as cartilaginous invasion is associated with a lower response ate to radiotherapy and a high risk of tumor recurrence. MR imaging is significantly more SensIti’e than spiral CT in detecting neoplastic cartilage invasion. However spiral CT is significantly more specific than MRI.
For lymph nodes involvement, it is found that spiral CT is able to show metastases in normal size lymph nodes and is therefore considered the best imaging modality for assessing lymph nodes involvement. On the other hand MRI is accurate than spiral CT in detection of vascular invasion of blood vessels of the neck.
Both spiral CT and MRI effectively predict the outcome of radiation therapy in patients with laryngeal carcinoma by correlation the pre-therapeutic imaging findings with the local tumor control rate after radiotherapy.
Both spiral CT and MRI can be used to follow up the patients with laryngeal carcinoma following radiotherapy or surgery for detection of recurrent tumor, vet it is found that the most accurate method in detecting tumor recurrence is the positron emission tomography (PET).