Posterior Cranial Fossa Tumors Symptoms

Since the dimensions of the posterior cranial fossa are small, CSF blockage and other related symptoms would be the early ones of the tumors of the posterior cranial fossa. Headache which is associated with vomiting-which is projectile – can be seen. The suboccipital headache with frontal or nuchal and neck irradiation would be among the early symptoms. Forth ventricle tumors are mainly associated with vomiting due to vagus bulbar centers direct compression by the tumors.

Cerebellar hemispheres tumors cause various symptoms like tremor – in case of cerebellar peduncles involvement-, dysmetria, bradykinesia, adiadochokinesia, hypotonia in the homolateral limbs muscles, uncertain gate and homolateral upper limb along the trunk. Cerebellar vermis tumors are associated with antalgic posture or stance in extension or flexion, stiffness, pain or rigidity in nuchal muscles, gait disturbances -with closed eyes in early stages and even with open eyes in late stages – which are broad based and uncertain with backward falling tendency. Vertigo during head movements, monotonous, marked and explosive voice are the symptoms of the forth ventricle tumors.

Acoustic intrameatal meningiomas can be associated with progressive hearing loss, facial paresis in periphery or tinnitus. These are not very much common tumors. Internal auditory canal and a small dura-arachnoid recess which is located in that, is the origin which these tumors arise from that. In case of bone invasion by the tumors, hyperostosis can be seen by radiological means although preoperative diagnosis of such tumors is unlikely. Fifth to Sixth decade of life is the life time which the appearance of such tumors is prevalent.

Internal auditory canal with CP-Angle extension and sometimes labyrinth, is the origin of the acoustic neurinomas. Dysequilibrium, unilateral hearing loss, high tones associated tinnitus and rarely vertigo are the symptoms of intracanalicular acoustic neurinomas. Corneal hypoesthesia is seen in trigeminal involvement of extracanalicular tumors. In case of hearing loss suspicion, homolateral corneal reflex should be tested. Corneal reflex absence in presence of hypoacusis, determines early diagnosis. Asymmetrical or unilateral sensorineural hearing loss, can be seen in tone audiogram. In five percent of intracanalicular or small tumors, hearing ability would be normal. Descrimination decreasing may be seen during vocal audiogram on the affected side. Intracanalicular tumors and retrocochlear pathologies can be tested with brainstem auditory evoked response. In case there would not be any ischemia, involvement or compression of the cochlear nerve by the tumors, about thirty three percent false negative results can be seen during the test. Having knowledge about the main symptoms of the posterior cranial fossa tumors, would be important in early diagnosis of such tumors and making appropriate treatment decisions about such tumors [1-20].

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