 Hello everyone, I am Dr. Labya Ayesha, junior resident department of radio diagnosis in MJ Medical College and Hospital Navi, Mumbai, presenting a paper on role of MRI in evaluation of primary intracranial tumors along with my co-author Dr. Pratik Patil, associate professor and under the guidance of Dr. Ashutosh Chitney sir. Primary intracranial tumors show diverse group of pathologic types derived from the area cells in central nervous system. The incidence is around 4 per 1 lakh population and the diagnosis is often delayed because of delayed initial sign symptoms, vague and nonspecific presentation. MRI is a highly sensitive imaging modality which allows accurate detection of legion location, its extent, mass effect, atrophy and hemorrhage and a better differentiation between vascular structure and adjacent barren schema. MRI plays an important role in all phases of patient management starting from diagnosis, treatment plan, response to treatment and recurrence. In this study, we reviewed the salient features of different types of intracranial tumors and their appearances on MRI. Our aim is to study the role of MRI as a method of investigation in diagnosis of primary intracranial tumors and our objectives are to detect, localize and diagnose primary intracranial tumors based on their characteristic MR appearances and to assist their patterns, extent and mass effect. This is a retrospective study done in MGM hospital in Navi Mumbai over a period of 6 months from November 2022 to April 2023. A total of 20 patients were included in the study and the patients ages range from 9 years to 86 years. All patients were scanned on Toshiba 1.5 Tesla MRI machine. Diagnosis was made based on the typical MR appearances, location, extent and associated features. This study includes total 20 cases. Out of the 6 cases are of meningioma, 3 cases of vestibular schwannoma, 3 cases of pituitary macrowadinoma, 1 case of craniofaryngeoma, 1 case of ependymoma, 1 case of pyrocytic astrocytoma, 1 case of glioblastoma, 1 case of glioma, 1 case of hypothermic hematoma, 1 case of caudoma and 1 case of pineal pyrantimal tumor. Now starting with case number 1, a case of meningioma in a 68 year old male patient presented with altered sensorium. The image is showing a well-defined mass lesion appearing hyper intense on T2 and flare involving the right frontoperitotemporal lobe, separated from brain parenchyma by a CSF cleft and causing compression in the form of midline shift and displacement of right lateral ventricle showing dural clefts and a dural tail sign and effacement of adjacent chalki and gyrel. Now moving to case number 2, a case of left sided vestibular schwannoma in a 38 year old female presented with heric and giddiness. The image shows well-defined T2 hyper intense lesion arising from left cerebellum pontine angle extending into left internal auditory and showing homogenous post-contrast enhancement. Moving to case number 3, a case of pituitary macro adenoma in a 44 year old male presented with heric and visual disturbances. The image shows a well-defined mass arising from cellar causing its mild expansion and it shows narrowing in the region of diaphragma celli giving rise to typical figure of age appearance and shows supracellular extension causing compression of optic chasma. Now moving to case number 4, a case of cranio parenchyoma in a 25 year old female patient presented with heric and visual disturbances. A well-defined mass appearing hyper intense on T2 and on post-contrast enhancement showing a peripheral thin rim of enhancement and causing compression of optic chasma. Now moving to the next case, a case of epandymoma in a 35 year old female patient presented with heric and neck pain. The image shows a well-defined mass appearing hyper intense on T2 showing multiple flare hyper intense septic within appearing hyper intense on T1 and showing heterogeneous peripheral post-contrast enhancement along with enhancing septic within arising from the floor of port ventricle causing its dilatation. Now moving to the next case, a case of pylocytic astrocytoma in a 25 year old female presented with persistent heric. The image shows a large solid cystic lesion in the right cerebellar hemisphere. The cystic component is appearing hyper intense on T2, hyper intense on T1 and showing bright post-contrast enhancement and it is causing displacement and effacing the port ventricle. Now moving to the next case, a case of glioblastoma in a 53 year old male presented with chronic headache and vomiting. A large extra axial mass arising from splenium of corpus callus on left side and in left parietal lobe appearing heterogeneously hyper intense on T2 flare and showing avid peripheral post-contrast enhancement with non-enhancing central areas within surrounded by diffuse perilegenal edema and showing an extra cranial extension through a bony defect and causing extreme compression of occipital horn and body of left lateral ventricle. Now moving to the next case, a case of glioma in a 49 year old male patient presented with headache and seizures. The image shows a large mass centered on genu of corpus callus extending into both frontal lobes and showing heterogeneous enhancement with central non-enhancing areas within, suggestive of intralesional hemorrhage and necrosis. Moving to the next case, a case of hypothalamic hematoma in a 9 year old male patient presented with seizures. The image shows a well defined mass arising in the region of hypothalamus on the left side. Moving to the next case, a case of cordoma in a 28 year old menial patient presented with headache and epistaxis. The mass involving nasopharynx, clivus, inferior aspect of pons and the cellular sticker. It is showing few small T2 hyper intensities and vivid post-contrast enhancement. And lastly, a case of pineal parenchyma tumor in a 39 year old male patient presented with headache and painful eye movements. The image shows heterogeneously hyper intense T2 signal intensity mass arising in the region of pineal gland comprising the tectum. Now the conclusion, MRI is a powerful non-invasive rapid and utmost important modality in detecting intracranial tumors. MRI with excellent capture of soft tissue anatomy, better delineation of pathologies, increased contrast discrimination and its ability to obtain images in different planes can better define precise location relative to important new anatomical structures. Its extent, mass effect, relationship with ventricles and vascular structures, presence and severity of secondary changes like hemorrhages, herniation, complications which is extremely important for optimal surgical radiotherapy, planning and evaluation of treatment response and recurrence and it helps on neurosurgeon to plan for surgery and the references.