Analysis of Cerebrospinal Fluid Pressure Estimation Using Formulae Derived From Clinical Data

Abstract

PURPOSE. To evaluate a frequently used regression model and a new, modified regression model to estimate cerebrospinal fluid pressure (CSFP). METHODS. Datasets from the Beijing iCOP study from Tongren Hospital, Beijing, China, and the Mayo Clinic, Rochester, Minnesota, were tested in this retrospective, case-control study. An often-used regression model derived from the Beijing iCOP dataset, but without radiographic data, was used to predict CSFP by using demographic and physiologic data. A regression model was created using the Mayo Clinic dataset and tested against a validation group. The Mayo Clinic-derived formula was also tested against the Beijing Eye Study population. Intraclass correlation was used to assess predicted versus actual CSFP. RESULTS. The Beijing-derived regression equation was reported to have an intraclass correlation coefficient (ICC) of 0.71, indicating strong correlation between predicted and actual CSFP in the study population. The Beijing iCOP regression model poorly predicted CSFP in the Mayo Clinic population with an ICC of 0.14. The Mayo Clinic-derived regression model similarly did not predict CSFP in its Mayo Clinic validation group (ICC 0.28 6 0.04) nor in the Beijing Eye Study population (ICC 0.06). CONCLUSIONS. Formulae used to predict CSFP derived from clinical data fared poorly against a large retrospective dataset. This may be related to differences in lumbar puncture technique, in the populations tested, or the timing of collection of physiologic variables in the Mayo Clinic dataset. Caution should be used when interpreting results based on formulaic derivation of CSFP.

Cerebrospinal fluid opening pressure in clinical practice – a prospective study

“…Our studies as well as those of Fleischman [7] suggest that more differentiated cut-offs, taking into consideration both age, gender and BMI should be used. Fleischman and coworkers have, more recently, based on retrospective clinical data from the Mayo clinic as well as data from Xie and coworkers from Beijing, compared estimation of CSFOP using regression model derived formulae with measured CSFOP values [8,15]. Though these models in addition to age and BMI also included blood pressure, model performance was similar to our results.…”

Prevalence of Retinal Vein Occlusions and Estimated Cerebrospinal Fluid Pressure: The Kailuan Eye Study

“…Although the eCSFP correlated relatively well with measured CSFP values in a previous study, one must bear in mind that the eCSFP value were just rough approximations needing further validation. 38 In that context, it has also to be considered that the width of the orbital cerebrospinal fluid space was not taken into account, since it was not feasible to measure it in a large community-based investigation. Since a wider orbital cerebrospinal fluid space is associated with higher CSFP and has also been taken as a surrogate for CSFP, one may think however that the parameter of CSFP already contains the orbital cerebrospinal fluid space width as parameter.…”

Studies Utilizing Current Estimated CSF Pressure Equations Should Not Be Conducted and Published [Letter]

“…However, we were troubled by the methodology employed by the study team. While we appreciate the mention of our study 2 that had found that formulae used to predict CSFP derived from clinical data were unable to accurately estimate CSF pressures, we were surprised that this formula was nonetheless used in the current study.…”