Lateral ventricle tumor are rare, and account for 50% of all intraventricular tumors in adults and 25% in children. Although these neoplasms are easily detected with computed tomography (CT) and magnetic resonance imaging (MRI), both techniques are relatively unspecific in identifying the type of tumor. However, few imaging patterns are specific for a particular pathological process and useful conclusions can be made from the morphological appearance of the lesion, its location and enhancement pattern. The aim of this article was to review and illustrate the CT and MRI findings of a wide spectrum of tumors of the lateral ventricle. We reviewed choroid plexus tumors, meningioma, subependymal giant cell astrocytoma, central neurocytoma, and less frequent lesion such as lymphoma and metastases 1).
The former include meningiomas, ependymomas, colloid cysts, metastatic tumors, astrocytomas, oligodendrogliomas, or glioblastomas.
Choroid plexus papillomas (CPP) are uncommon benign brain tumors that usually arise in the fourth ventricle in adults and lateral ventricles in children.
For the radiological analyses, the tumors of the lateral ventricle are classified into two groups, as follows: 1. Intraventricular tumors arise in the projection of the choroid plexus, the tela chorioidea and the ependyma and grow in the lateral ventricle. 2. Paraventricular tumors arise from the wall of the neuroglia not only bulge into ventricle, but in addition infliltrate the substance of the surrounding brain. Following conclusions are obtained. (1) Unilateral hydrocephalus, which is shown clearly by vascular displacements in subependymal veins, is demonstrated in both tumors groups. (2) There are different findings on the feeding arteries, the draining veins and the tumor stains between two tumors groups. (3) In the intraventricular tumors groups, the anterior choroidal artery supplying the tumor is its the plexal segments and atrial segments. (4) On the other hand, the paraventricular tumors group, the anterior choroidal artery supplying the tumor is its the superior penetrating branch to the cerebral parenchyma. (5) Cerebral angiograms can reveal the definite signs of the intraventricular mass, but it is sometimes difficult to evaluate whether its space occupying lesions infiltrates the cerebral substance below the wall of the lateral ventricle, or not. (6) CT scan is useful neuroradiological method in the different diagnosis between two tumor groups, and CT scan provides and anantomical diagnosis rather than a histological one. (7) The accurate diagnosis of the tumors of the lateral ventricle can be demonstrated by both cerebral angiograms and CT scan 3).
A total of 72 patients underwent surgery for lateral ventricle tumors. The mean patient age was 39 years (range, 6 mo to 78 yr). Raised intracranial pressure occurred in 53% of patients, followed by mental disturbances or psychiatric symptoms (32%) and motor deficits (21%). The transcortical approach was used in 44 patients, and an interhemispheric approach was used in 28 patients; a transcallosal approach was used in 16 patients, and a parasplenial approach was used in 12 patients. Neuropsychological tests were performed in selected patients.
Total resection was performed in 82% of patients. Sixty-five percent of tumors were benign and low-grade tumors. There was no surgical mortality, and the morbidity rate was 11%. Postoperative epilepsy (5.9%) was significantly increased in the transcortical group. The mean follow-up period was 55 months; 59% of patients achieved good recovery and moderate disability. In postoperative neuropsychological testing sessions, deficits in verbal memory were observed in six patients (8%). Final morbidity correlated well with preoperative clinical condition and pathological diagnosis.
Lateral ventricle tumors can be treated best by careful selection of the approach according to tumor origin and development. Overall, the transcallosal approach is preferred, but in patients with transependymal growth or large primary or secondary ventricular tumors, the transcortical is a better option 4).