Variability in Lumbar Puncture Assessment in Patients With Papilledema From Idiopathic Intracranial Hypertension: A...

The evaluation of papilledema often requires lumbar puncture (LP) to measure opening pressure and analyze cerebrospinal fluid (CSF). However, opening pressure can be reported in different units (eg, cm H 2 O, mm Hg), and the ordering practices of CSF constituents can vary. This study aims to evaluate the pattern of opening pressure assessment and CSF laboratory ordering practices in patients with papilledema due to idiopathic intracranial hypertension (IIH).

This was a retrospective review across 3 institutions based in Houston, TX. Information was obtained for patients with optic disc edema suspected of papilledema due to IIH who presented between 2009 and 2024. Patients were included if their records contained an LP procedure note for the evaluation of papilledema. Opening pressure units and CSF constituents were recorded.

A total of 227 charts were included, consisting of 317 opening pressure measurements and 245 cases with at least 1 documented CSF laboratory order. We found that units of measurement for opening pressure were reported as cm H 2 O (71%), cm (10%), no units (9%), mm H 2 O (3%), mm Hg (3%), cm CSF (2%), mm (1%), and cm/H 2 O (1%). Among the CSF samples sent for analysis, 99% included cell count, 97% included glucose, 95% included protein, 75% included culture, and 35% included additional laboratory measures.

Inconsistencies in LP measurement units and CSF laboratory orders may lead to misinterpretation, potentially impacting patient care for those suspected of having papilledema due to IIH. We recommend greater standardization of the assessment of LP results for those undergoing evaluation for papilledema suspected due to IIH.