Brain tumor is one of the most devastating forms of human illness, especially when occurring in the posterior fossa cranial tumors. Posterior fossa tumors are considered critical brain tumors primarily because of the limited space within the posterior fossa tumors and the potential involvement of vital brain stem nuclei. The objective: To describe and evaluate the magnetic resonance imaging pattern of posterior cranial fossa tumors and to determine their clinical Presentations. Magnetic resonance imaging was introduced as an integral part of management of patients suspected to have infratentorial tumors. Results: The most frequent symptoms in patients with posterior cranial fossa tumors were headache which occurred in (48%), Vomiting occurs in (14%), macrocephaly in (14%), Meningismus in (8%), ,blurring of vision in (6%), Truncal ataxia in (4%), irritability in (4%), (Tinnitus in (4%), (limb ataxia in (2%), hearing loss in (2%), and nausea in (2%). The clinical presentation depends on the site of the tumor. This is a descriptive, retrospective study carried out during the Period from April 2016 to December 2016, at the antalya Medical Center, the Khartoum Advanced diagnostic Centre and Royal Care International Hospital. The study included fifty patients 26 males and 24 females for all age groups. Cerebellar metastasis were found in (9 cases), Brainstem gliomas (11 cases), medulloblastoma (6 cases), (meningioma (5 cases), acoustic schwannoma (5 cases), astrocytomas (4 cases), ependymomas 4) cases), (choroid plexus papilloma 2) cases) hemangioblastoma (2 cases) and Hemangiopericytoma (2 cases). In most cases it was Possible to predict the histological type of these tumors by magnetic resonance imaging. The search for the residual fourth ventricle cavity and defining its location were the first step in differential diagnosis. Because signal abnormalities on magnetic resonance imaging are most often not specific, it is essential to take into account the clinical and topographic characteristics of the lesion to establish an appropriate differential diagnosis. The main patterns of posterior cranial fossa tumors are presented. Brain metastases are common in A dult, in contrast to lepto-meningeal metastasis. This, because of high tissue contrast, multiplanar imaging and minimal artifacts. Magnetic resonance imaging proved to be the method of choice for planning surgery and for the follow-up of tumors in the posterior cranial fossa.
