Snapshot A 25-year-old woman presents to the emergency department with left upper extremity weakness and urinary retention. The patient was admitted due to suspicion of multiple sclerosis and a lumbar puncture was performed. Cerebrospinal fluid demonstrated oligoclonal bands and an elevated IgG index. The patient subsequently developed a headache that is worse when sitting or standing and improves when lying flat in bed. (Positional orthostatic headaches from a cerebrospinal fluid leak caused by lumbar puncture). Introduction Lumbar puncture (LP) is a procedure where a spinal needle is advanced into the subarachnoid space in order to collect cerebral spinal fluid (CSF) login to view 12 more bullets Cerebrospinal Fluid AnalysisTestNormalBacterialViralFungal/TBOpening pressure≤ 20 cm H 2O↑normal or slightly ↑↑ColorClearCloudyClearCloudyCell count0-5 cells/µL↑ (PMN)↑ (Lymphocytes)↑ (Lymphocytes)Protein< 45 mg/dL↑Slighty ↑↑CSF:Serum glucose> 0.6↓Normal↓ Technique Patient position login to view 5 more bullets Needle entry login to view 3 more bullets In cases where there are unsuccessful attempts in obtaining CSF, imaging guidance can be used such as login to view 2 more bullets Complications Post-LP headache Infection Bleeding Cerebral herniation Traumatic lumbar puncture login to view 3 more bullets