BACKGROUND AND PURPOSE: Localization of the culprit CSF leak in patients with spontaneous intracranial hypotension can be difficult and is inconsistently achieved. We present a high yield systematic imaging strategy using brain and spine MRI combined with digital subtraction myelography for CSF leak localization. MATERIALS AND METHODS: During a 2-year period, patients with spontaneous intracranial hypotension at our institution underwent MR imaging to determine the presence or absence of a spinal longitudinal extradural collection. Digital subtraction myelography was then performed in patients positive for spinal longitudinal extradural CSF collection primarily in the prone position and in patients negative for spinal longitudinal extradural CSF collection in the lateral decubitus positions. RESULTS: Thirty-one consecutive patients with spontaneous intracranial hypotension were included. The site of CSF leakage was definitively located in 27 (87%). Of these, 21 were positive for spinal longitudinal extradural CSF collection and categorized as having a ventral (type 1, fifteen [48%]) or lateral dural tear (type 2; four [13%]). Ten patients were negative for spinal longitudinal extradural CSF collection and were categorized as having a CSF-venous fistula (type 3, seven [23%]) or distal nerve root sleeve leak (type 4, one [3%]). The locations of leakage of 2 patients positive for spinal longitudinal extradural CSF collection remain undefined due to resolution of spontaneous intracranial hypotension before repeat digital subtraction myelography. In 2 (7%) patients negative for spinal longitudinal extradural CSF collection, the site of leakage could not be localized. Nine of 21 (43%) patients positive for spinal longitudinal extradural CSF collection were treated successfully with an epidural blood patch, and 12 required an operation. Of the 10 patients negative for spinal longitudinal extradural CSF collection (8 localized), none were effectively treated with an epidural blood patch, and all have undergone (n = 7) or are awaiting (n = 1) an operation. CONCLUSIONS: Patients positive for spinal longitudinal extradural CSF collection are best positioned prone for digital subtraction myelography and may warrant additional attempts at a directed epidural blood patch. Patients negative for spinal longitudinal extradural CSF collection are best evaluated in the decubitus positions to reveal a CSF-venous fistula, common in this population. Patients with CSF-venous fistula may forgo further epidural blood patch treatment and go on to surgical repair.

The recently discovered glymphatic system is distinctive of the central nervous system and allows for homeostatic “circulation” of interstitial fluid, making familiarity with the relevant anatomy a... Normal physiologic function of organs requires a circulation of interstitial fluid to deliver nutrients and clear cellular waste products. Lymphatic vessels serve as collectors of this fluid in mos...

Multiple techniques being developed to image glymphatic transport are reviewed that are nearing clinical implementation and will allow detection of its altered function that contributes to patholog... The glymphatic system is a recently discovered network unique to the central nervous system that allows for dynamic exchange of interstitial fluid (ISF) and cerebrospinal fluid (CSF). As detailed i...

BACKGROUND AND PURPOSE: Spinal arteriovenous shunts below the conus constitute 3 types of lesions, which have previously been mainly described in case reports, given their rarity, and are sometimes misdiagnosed. The purpose of this study was to describe the features of each type and compare these types as to epidemiologic features, clinical and radiologic presentations, treatment, and outcomes in a consecutive series of 48 cases. MATERIALS AND METHODS: The prospectively collected data bases of 2 referral centers for spinal vascular lesions were retrospectively reviewed. Spinal arteriovenous shunts below the conus were defined as all dural and intradural shunts below the conus medullaris. Clinical features, radiologic findings, treatment results, and clinical outcomes were assessed. RESULTS: There were filum terminale arteriovenous fistulas in 11 patients (22.9%), radicular arteriovenous shunts in 7 patients (14.6%), and spinal dural arteriovenous fistulas in 30 patients (62.5%). Radicular arteriovenous shunts presented at a younger age (P = .017) and with a higher incidence of back pain symptoms (P = .037). A tethered spinal cord was found in 54.5% of patients with filum terminale arteriovenous fistulas and 23.3% of patients with spinal dural arteriovenous fistulas. After treatment, the angiographic complete obliteration rate was 89.4% and spinal function was improved significantly (P < .001). CONCLUSIONS: Three groups of spinal arteriovenous shunts below the conus can be differentiated according to clinical and radiologic features. Filum terminale arteriovenous fistulas are frequently associated with dysraphic malformations, which may suggest a particular embryologic origin.

Background and Objectives Small iatrogenic brain infarcts are often seen on diffusion-weighted MRI (DWI) following surgical or endovascular procedures, but there are few data on their clinical effects. We examined the association of iatrogenic infarcts with outcomes in the ENACT (Evaluating Neuroprotection in Aneurysm Coiling Therapy) randomized controlled trial of nerinetide in patients undergoing endovascular repair of intracranial aneurysms. Methods In this post hoc analysis, we used multivariable models to evaluate the association of the presence and number of iatrogenic infarcts on DWI with neurologic impairment (NIH Stroke Scale [NIHSS]), functional status (modified Rankin Scale [mRS]), and cognitive and neuropsychiatric outcomes (30-minute test battery) at 1–4 days and 30 days postprocedure. We also related infarct number to a z score–derived composite outcome score using quantile regression. Results Among 184 patients (median age 56 years [interquartile range (IQR) 50–64]), 124 (67.4%) had postprocedural DWI lesions (median 4, IQR 2–10.5). Nerinetide treatment was associated with fewer iatrogenic infarcts but no overall significant clinical treatment effects. Patients with infarcts had lower Mini-Mental State Examination (MMSE) scores at 2–4 days (median 28 vs 29, adjusted coefficient [acoef] −1.11, 95% CI −1.88 to −0.34, p = 0.005). Higher lesion counts were associated with worse day 1 NIHSS (adjusted odds ratio for NIHSS ≥1: 1.07, 1.02–1.12, p = 0.009), day 2–4 mRS (adjusted common odds ratio [acOR] 1.05, 1.01–1.09, p = 0.005), and day 2–4 MMSE (acoef −0.07, −0.13 to −0.003, p = 0.040) scores. At 30 days, infarct number remained associated with worse mRS (acOR 1.04, 1.01–1.07, p = 0.016) and Hopkins Verbal Learning Test (HVLT) delayed recall scores (acoef −0.21, −0.39 to −0.03, p = 0.020). Patients with infarcts trended towards lower 30-day Digit Symbol Substitution Test (DSST) scores (acoef −3.73, −7.36 to −0.10, p = 0.044). Higher lesion count was associated with worse composite outcome scores at both 1–4 days and 30 days (30-day acoef −0.12, 95% CI −0.21 to −0.03, p = 0.008). Among those with infarcts, day 1 NIHSS and day 2–4 mRS correlated with 30-day NIHSS, DSST, HVLT, and mRS scores, whereas day 2–4 MMSE correlated with 30-day NIHSS and DSST scores (Spearman ρ 0.47, p = 0.001). Discussion Iatrogenic brain infarcts were associated with subtle differences in postprocedural (1–4 days) and 30-day outcomes on different measures in this middle-aged cohort, with earlier dysfunction correlating with later differences. Trial Registration Information Clinical trials registration NCT00728182.