[8] Erythrocyte count may also be normal or high, and at times quite high. Low CSF pressures and struggle to secure CSF flow to measure the OP and obtain fluid can increase the likelihood of traumatic tap. The associated congestion of the epidural venous plexus will also increase the incidence RG-7388 solubility dmso of blood-tinged CSF. Glucose concentration, cytology, ad bacteriology should all be normal. Indium-111 is the radioisotope of choice. It is introduced intrathecally (IT) via an LP and its dynamics are followed by sequential
scanning at various intervals of up to 24 or even 48 hours. Normally after 24 hours, though often earlier, ample radioactivity can be detected over the cerebral convexities while no activity outside the dural sac is noted, unless there has been inadvertent
injection of part of the radioisotope extradurally or if some of the IT-injected radioisotope has extravasated through the dural puncture site. In CSF leaks, the following should be expected: The radioactivity should not extend much beyond the basal cisterns, and therefore, at 24 or even at 48 hours, there is paucity of activity over the cerebral convexities (Fig. 4A,B).[34-36] Although an “indirect evidence,” this is the most common and most reliable cisternographic abnormality in active CSF leaks. This is particularly helpful when the clinical and MRI findings are atypical, insufficient, https://www.selleckchem.com/products/BIRB-796-(Doramapimod).html or unconvincing and, therefore, leaving the clinician with a fundamental uncertainty about the diagnosis. Presence of parathecal activity as a “direct evidence” of leak pointing to the level or the approximate site of the leak (Fig. 4B,C), unfortunately, is far less commonly noted than paucity of activity over cerebral convexities. Of note, meningeal diverticula – if large enough – may appear as foci of parathecal activity and Aurora Kinase sometimes may not be reliably distinguished from
actual sites of leak. Computed tomography myelography (CTM) is frequently needed to advance the workup appropriately, not only to enable this differentiation but to confirm the actual site of the leak. Meningeal diverticula may or may not be the actual site of the leak even when they are large. Early appearance of radioactivity in the kidneys and urinary bladder (in less than 4 hours vs 6-24 hours) is a fairly common “indirect evidence,” indicating that the IT-introduced radioisotope has extravasated and entered the venous system quickly with subsequent early renal clearance and early appearance in the urinary bladder. This finding, however, is of limited reliability and can be affected by partial extradural radioisotope injection or perhaps even more commonly by extravasation of IT-injected radioisotope from the dural puncture site back to the epidural tissues. This is identical to the mechanism involved in postdural puncture headaches. MRI has truly revolutionized our understanding of SIH.