Jonathan is a 11-year-old boy scheduled to receive the follo…

Jonathan is a 11-year-old boy scheduled to receive the following induction chemotherapy regimen for his diagnosis of acute lymphocytic leukemia. He weighs 25 kg. His chemotherapy regimen includes the following agents Induction chemotherapy Cyclophosphamide Daunorubicin Vincristine Prednisone L-Asparaginase Intrathecal chemotherapy prophylaxis Methotrexate Cytarabine The dose for Jonathan’s intrathecal chemotherapy should be calculated as:

A patient woke up one morning and experienced nausea and vom…

A patient woke up one morning and experienced nausea and vomiting followed by a sudden headache posteriorly.  In the emergency department, they present with the following clinical signs:  severe truncal ataxia, vertigo, unsteady gait with a wide base of support. There are no brainstem signs. What vascular structure is affected?