Ectopic anterior cerebellum (ala lobule centralis)

In this case report we present an adolescent girl who was referred to our radiology department for assessment with advanced magnetic resonance (MR) imaging on suspicion of low-grade quadrigeminal cistern neoplasm on 1.5 Tesla MR examination. We were able to evaluate detailed cerebellar anatomy more clearly, and detected that the lesion was compatible with ectopic cerebellar tissue (a very rare developmental variation) on submillimetric 3-dimensional (3D) images from a 3 Tesla MR unit which has a 32-channel head coil. Our findings were further supported by diffusion tensor imaging which clearly indicated that the lesion was a part of the cerebellum. Furthermore, MR spectroscopic metabolite ratios were in accordance with the characteristics of normal neuronal tissue. As far we know there is no published report that contains similar findings to those of our patient. In conclusion, cranial MR images, if possible in 3D format (with very small isotropic voxels) should be obtained for the precise diagnosis of the lesions located in this region; in addition, the differential diagnostic list should be well known and advanced imaging techniques should be used when necessary

Tumors of pineal cell origin

Tumors of pineal cell origin are rare intracranial lesions. They are the second most common entity encountered in the pineal gland, after tumors of germ cell origin. They are classified according to their differentiation in pineocytomas (World Health Organization [WHO] grade I tumor), pineal parenchymal tumors of intermediate differentiation, papillary tumors of the pineal region, and pineoblastomas (WHO grade 4 tumor). Differentiation between pineal and germ cell tumors is essential, and for this purpose serum and cerebrospinal fluid (CSF) markers are used, alongside imaging techniques. Often, the only way to differentiate these two types of tumors is through a biopsy, which may be carried out with or without a simultaneous third ventriculocisternostomy. Retrospective series show an association between the extent of resection and improved outcomes, and benign lesions may be cured by performing a gross total resection. However, the approaches to this region are highly complex, because of the plethora of essential neuroanatomical structures in the area. The approaches need to be tailored to the specific anatomy of the patient and should aim at minimizing surgical morbidity. Because of their complexity, these lesions should mainly be performed in centers with sufficient experience in the treatment of pineal region lesions.</p