23 Intraventricular Masses

CLINICAL IMAGAGINGAN ATLAS OF DIFFERENTIAL DAIGNOSIS

EISENBERG

DR. Muhammad Bin Zulfiqar PGR-FCPS III SIMS/SHL

• Fig SK 23-1 Choroid plexus papilloma. T1-weighted coronal image shows a lobulated isointense mass (arrows) in a markedly dilated right lateral ventricle.

• Fig SK 23-2 Colloid cyst. T1-weighted coronal MR scan shows a hyperintense mass in the third ventricle just posterior to the foramen of Monro. There is ventricular dilatation in this elderly man with a history of recurrent headache.27

• Fig SK 23-3 Intraventricular meningioma. Well-circumscribed mass (arrow) in the posterior aspect of the left lateral ventricle in a patient with neurofibromatosis

• Fig SK 23-4 Ependymoma. Large intraventricular mass (arrows) located in the third ventricle and anterior horns of both lateral ventricles; there is associated hydrocephalus. Areas of greatest hyperintensity in the tumor represent subacute hemorrhage.34

• Fig SK 23-5 Giant cell astrocytoma. (A) Contrast-enhanced T1-weighted MR image shows a markedly hyperintense intraventricular mass (arrowhead) in this young boy with clinical stigmata of tuberous sclerosis. (B) T2-weighted image at another level shows characteristic high-signal cortical hamartomas (arrows) as well as dense calcifications (arrowheads).35

• Fig SK 23-6 Dermoid cyst. Coronal T1-weighted MR image shows a hyperintense mass (arrows) filling the dilated right temporal horn. The lateral and third ventricles are enlarged.36

• Fig SK 23-7 Epidermoid tumor. Sagittal T-weighted MR image shows a large mass filling the fourth ventricle. The mass has a slightly higher signal intensity than CSF. It depresses the brainstem (black arrows) and elevates the tonsil and inferior vermis (white arrows).

• Fig SK 23-8 Primitive neuroectodermal tumor. (A) Sagittal T1-weighted MR image shows a large, inhomogeneously isointense mass (arrows) filling the entire body of the left lateral ventricle and compressing the third ventricle, midbrain, and upper vermis of the cerebellum. (B) Coronal T1-weighted scan demonstrates intense enhancement of the lesion.36

• SK 23-9 Malignant teratoma. (A) Coronal T1-weighted MR image shows a large, irregular, lobulated mass (arrows) of inhomogeneous hypointensity in the body and occipital horn of the left lateral ventricle. (B) On the axial proton-density-weighted image, the mass is hyperintense (arrows).36

• Fig SK 23-10 Oligodendroglioma. Axial T1-weighted MR image shows a large lobulated isointense mass (arrows) with cystic components (arrowheads) involving the septum pellucidum and bodies of the lateral ventricles.36

• Fig SK 23-11 Neurocytoma. (A) Axial T2-weighted MR image shows the heterogeneous appearance of the lesion, reflecting the presence of cystic spaces and calcifications. (B) CT scan shows coarse, conglomerate calcification and large cystic areas within the intraventricular tumor.37

• Fig SK 23-12 Hemorrhagic metastatic melanoma. Sagittal T1-weighted MR image shows a round mass filling the left frontal horn near the foramen of Monro. The mass has a hyperintense rim (arrows), most likely representing methemoglobin, and a hypointense center (arrowheads).36