PT  - JOURNAL ARTICLE
AU  - Kranz, P.G.
AU  - Malinzak, M.D.
AU  - Gray, L.
AU  - Willhite, J.
AU  - Amrhein, T.J.
TI  - Resisted Inspiration Improves Visualization of CSF-Venous Fistulas in Spontaneous Intracranial Hypotension
AID  - 10.3174/ajnr.A7927
DP  - 2023 Aug 01
TA  - American Journal of Neuroradiology
PG  - 994--998
VI  - 44
IP  - 8
4099  - http://www.ajnr.org/content/44/8/994.short
4100  - http://www.ajnr.org/content/44/8/994.full
SO  - Am. J. Neuroradiol.2023 Aug 01; 44
AB  - BACKGROUND AND PURPOSE: CSF-venous fistulas are an important cause of spontaneous intracranial hypotension but are challenging to detect. A newly described technique known as resisted inspiration has been found to augment the CSF-venous pressure gradient and was hypothesized to be of potential use in CSF-venous fistula detection but has not yet been investigated in patients with spontaneous intracranial hypotension. The purpose of this investigation was to determine whether resisted inspiration results in improved visibility of CSF-venous fistulas on CT myelography in patients with spontaneous intracranial hypotension.MATERIALS AND METHODS: A retrospective cohort of patients underwent CT myelography from November 2022 to January 2023. Patients with an observed or suspected CSF-venous fistula identified during CT myelography using standard maximum suspended inspiration were immediately rescanned using resisted inspiration and the Valsalva maneuver. The visibility of the CSF-venous fistula among these 3 respiratory phases was compared, and changes in venous drainage patterns between phases were assessed.RESULTS: Eight patients with confirmed CSF-venous fistulas who underwent CT myelography using the 3-phase respiratory protocol were included. Visibility of the CSF-venous fistula was greatest during resisted inspiration in 5/8 (63%) of cases. Visibility was optimal with the Valsalva maneuver and maximum suspended inspiration in 1 case each, and it was equivalent in all respiratory phases in 1 case. In 2/8 (25%) cases, the pattern of venous drainage shifted between respiratory phases.CONCLUSIONS: In patients with spontaneous intracranial hypotension, resisted inspiration improved visualization of CSF-venous fistulas in most, but not all, cases. Further investigation is needed to determine the impact of this technique on the overall diagnostic yield of myelography in this condition.CTFCT fluoroscopyCTMCT myelographyCVFCSF-venous fistulaDSMdigital subtraction myelogramSIHspontaneous intracranial hypotension