 Good morning everybody. Today I am going to present a case report scientific paper on posterior reversible encephalopathy syndrome in childhood leukemia. My name is Dr. Ramato Pal. I am the second year post-graduate trainee in the department of radio diagnosis, Nilathan Sirkar Medical College and Hospital Kolkata. So, posterior reversible encephalopathy syndrome that is PRESS is a clinical radiological syndrome characterized by headaches, seizures, altered mental status and visual loss and featured by white matter vasogenic edema affecting the posterior occipital and parietal lobes of the brain predominantly. PRESS was first described in 1996 by Hinche et al. It is commonly but not always associated with acute hypertension. The clinical syndrome is being increasingly recognized commonly because of improvement and availability of brain imaging. Associated conditions with PRESS are hypertension, preeclampsia or eclampsia, exposure to immunosuppressive drugs, chemotherapy, renal failure, infection or sepsis or shock and autoimmune diseases like acute globulitis and arthritis and lupus necropathy. In this case, we have present our case of a precursor B cell acute lymphoblastic leukemia patient with sudden onset neurological symptoms which was walked up using clinical findings, blood parameters and MRI findings. MRI was done using a GE sigma HD 1.5 Tesla MRI scanner. Imaging features of posterior reversible interphalopathy syndrome were found. Now coming to the clinical history, it is a five-year-old boy admitted in the hematology department suddenly who suddenly developed hypertension, altered sensorium, visual disturbances and seizures five days after starting off chemotherapy regimen for pre-B cell ALL. His diagnosis of pre-B cell ALL was done by peripheral blood smear, bone marrow examination and immunohistochemistry. He had been started on a regimen of daily six-mark apropurin and weekly tablet methotrexate along with IV vincristin and a steroid dexamethasone. Intrathacal methotrexate was also given to the patient. After the onset of the symptoms, blood parameters revealed an elevated CRP along with a very low platelet. Other hematological and blood biochemistry were in line with his disease condition. He was promptly started on anti-epileptics and anti-hypertensive and an MRI brain was done. The MRI revealed features suggestive of posterior reversible interphalopathy syndrome. Thus we came to a clinical radiological diagnosis of breast. Slowly a progressive movement of clinical symptoms, neurological symptoms and cognitive status was observed along with treatment. His chemotherapy treatment was restarted one month later. Now coming to the imaging findings. Here we will be comparing the imaging findings at the onset of symptoms and post-resolution of symptoms. At the onset of symptoms, axial brain MR imaging showed cortical and sub-particle hyperintensities due to vasogenic edema on T2FR-FSC weighted images. Whereas post-resolution of symptoms, axial brain MR imaging showed absence of hyperintensities due to near-resolution of the vasogenic edema. Similar findings were found in T2FR weighted images in which at the onset of symptoms there were cortical and sub-cortical hyperintensities which had resolved post-resolution of symptoms. Now coming to T2GRE sequences that were taken during the scan. In the T2GRE sequence at the onset of symptoms, axial brain MR imaging showed areas of focal patchy hemorrhages involving bilateral parietal and occipital lobes and right temporal lobe appearing as blooming artifact on T2GRE sequence. Whereas on post-resolution of symptoms, his brain, the MRI showed resolution of the focal hemorrhages that was seen earlier. And lastly, we come to DWI images. In DWI images, as we can see clearly over here at the onset of symptoms, there is an area of hyperintensity which is actually the T2 shine-through that is noted over here and which has resolved post-resolution of symptoms. Now coming to the discussion part. Posterior reversible encephalopathy syndrome that is praise was first described by Hinche et al. in 1996. Though the pathogenesis of praise is yet to be understood, the most widely accepted explanation is cerebral auto-regulation and increased perfusion with vasodilation. There is a greater predisposition for the regions of the posterior circulation of the brain likely due to relatively lesser sympathetic innervation than anterior circulation. Axial MR imaging showed reversible vasogenic edema in the cortical and sub-cortical white matter of the parietal occipital region in the most patients. In addition to a predominance for the parietal occipital region involvement of the frontal lobe, the posterior portion of the superior frontal gyrus and the temporal lobe can also be seen. Cerebellum, brinstem and thalamus are generally spared. Praise can be complicated by the presence of hemorrhage as seen in our case which demonstrated as focal patchy hemorrhages. This was in accordance with a study conducted by McKinney et al. 2007. On DWI weighted images, though the most common finding is iso-intensity, but DWI bright T2 shine-through as seen on our case can also be found. Diffusion restriction which is usually puncted surrounded by a much larger areas of vasogenic edema with no ensuing atrophic and also be found. This was in accordance to the studies conducted by Benaziria Bordor et al., McKinney et al. and Kovarubias et al. Apart from MRI, the other modalities of imaging that can be done in case of preciousness, in case of CT, the affected regions are generally hypotenating. And in angiography, there are signs of vasopressum or arthritis like diffuse vasoconstriction, focal vasoconstriction or vasodilation or a string of beat appearance. Now the major differentiates for posterior reversible encephalopathy syndrome are posterior circulation ischemia infarction, progressive multifocal leucoencephalopathy that is BML, vasculitis, encephalitis and sinus thrombosis. Thus to conclude, praise is a neurotoxic state coupled with a unique MR imaging appearance. Hypertension is believed to be the unifying precipitating factor in many cases, but it may occur also in normal telsips. Corticosteroid therapy primarily mediated by its effect on the mineralocorticoid receptor may lead to hypertension which may be the etiology of praise in this patient. But the implication of other cytotoxic drugs cannot be excluded. Hence, all patients on steroids should have strict blood pressure monitoring. And given the widespread use of steroids in the field of hematoconology, it is important to recognize praise as a rare but usually reversible complication, especially in pediatric patients receiving treatment for acute lymphoblastic leukemia and appropriate treatment should be initiated accordingly. After ruling out other causes which could result in a similar clinical presentation like CNS-HMRH, CNS leukemic infiltration and encephalitis. These are the references that I have used in my studies. Thank you for hearing me. Goodbye.