Many cases of abnormal brain masses may refer for stereotaxic biopsy (Strotaxic: It is a type of surgery that with the help of special and accurate tools, certain points of the brain are identified and by making a small cut in the scalp and creating a hole in the skull and dura, and with minimal damage to the brain tissue, it will be possible to reach that point and perform the desired actions as obtain tissue sample, thalamotomy ,pallidotomy, brachytherapy , electrode placement…). Among these lesions we can mention "MS" plaques, infectious lesions, granulomatous masses, ischemic lesions, vasculopathies, neoplastic tumors…Brain masses can be detected and differentiated with different modalities of "MRI", "MRS" and "MR perfusion" with a high percentage, and biopsy is not necessary for many of them. On the other hand, in some cases as possible diagnoses, the patient has been treated for a long time, but since there is no certain response from the treatment obtained, they are referred to have a pathology sample for a definitive diagnosis. Several cases in this regard have been biopsied by me, some of which confirmed the initial diagnosis, and some were contrary to the initial opinion. Plaques suspected of "MS Plaques " which are observed in "MRI", according to clinical signs and symptoms and the course of the disease and non-invasive paraclinical examinations, including "VEP","MRS" and "MR perfusion" can be recognized and differentiated with a high percentage, and the biopsy of MS Plaques are an invasive and unnecessary procedure, which may aggravated complications, and on the other hand, the result of the pathology, except in acute phases cases where macrophages and reactive cells are observed, due to the lack of access to specific and special "myelin" staining, is uncertain and it will be controversial. Nevertheless, sometimes the plaques are very large and even in acute phases cases, due to the high metabolism of the area, MRS may falsely suggest neoplasia, because increased choline level, and in these cases, they are referred for biopsy for definitive diagnosis.
During 33 years in four hospitals (Shohada,Tehran,Arad,Mehrad) By three Stereotaxic systems I have done over than 7000 brain lesions biopsies and Some of the most interesting brain lesions are introduced and discussed in this presentation with clinical description and imaging and pathology reports.