Practice Patterns and Opening Pressure Measurements Using Fluoroscopically Guided Lumbar Puncture

Abstract

BACKGROUND AND PURPOSE: Evidenced-based protocols for fluoroscopically guided LP do not exist. This study analyzed the fluoroscopically guided LP techniques currently used by practicing neuroradiologists.

Using Body Mass Index to Predict Needle Length in Fluoroscopy-Guided Lumbar Punctures

“…The patient population in the Abe et al study had a BMI of 22.6 (BMIC, normal) and included children and adults, while the BMI in our cohort of adult patients was 31.7 (BMIC, obese), which is more similar to the average BMI of 28.4 (BMIC, overweight) seen in the adult US population. 20 We believe our formula more accurately predicted the needle length than the formula of Ma et al 11 because in our cohort of 50 patients, the SD of weight (kilograms) of the patients was higher (24.2 versus 12.7 Kg). A formula derived from a wider range of patient weights suggests that the formula is potentially more applicable to a larger subset of the general population.…”

“…This finding is consistent with the practices of our institution and most other neuroradiology practices, where most of the FGLPs are performed at these 2 levels. 20 LPs are usually avoided at L4 -L5 and L5-S1 due to the higher incidence of degenerative changes and spinal canal stenosis 16 and the smaller cross-sectional area of thecal sac compared with L2-L3 and L3-L4, 15 which could cause a lower success rate. In addition, lumbar punctures at L4 -L5 are associated with twice the risk of traumatic lumbar puncture compared with L2-L3 and L3-L4, 7 which could lead to complications and confound results, especially in patients with concern for subarachnoid hemorrhage.…”

Difficult Lumbar Puncture: Pitfalls and Tips from the Trenches

“…19 The normal CSF pressure range is 6 -20 cm H 2 0 in adults and up to 25 cm H 2 0 in obese patients. 20 An opening pressure of Ͼ25 cm H 2 0 is diagnostic of IIH, in the correct clinical setting.…”

Effect of Patient Positioning on Cerebrospinal Fluid Opening Pressure

“…Although the diagnostic criteria for idiopathic intracranial hypertension (IIH) specify the measurement of cerebrospinal fluid (CSF) opening pressure (OP) in the lateral decubitus (LD) position (1), most fluoroscopic-guided LPs measure OP with the patient in the prone position (2). Most neuroradiologists appropriately add the needle length to the manometer when measuring prone OP, but some do not.…”