Myelographic Techniques for the Localization of CSF-Venous Fistulas: Updates in 2024.

CSF-venous fistulas (CVFs) are a common cause of spontaneous intracranial hypotension. Despite their relatively frequent occurrence, they can be exceedingly difficult to detect on imaging. Since the initial description of CVFs in 2014, the recognition and diagnosis of this type of CSF leak has continually increased. As a result of multi-institutional efforts, a wide spectrum of imaging modalities and specialized techniques for CVF detection is now available. It is important for radiologists to be familiar with the multitude of available techniques, because each has unique advantages and drawbacks. In this article, we review the spectrum of imaging modalities available for the detection of CVFs, explain the advantages and disadvantages of each, provide typical imaging examples, and discuss provocative maneuvers that may improve the conspicuity of CVFs. Discussed modalities include conventional CT myelography, dynamic myelography, digital subtraction myelography, conebeam CT myelography, decubitus CT myelography by using conventional energy-integrating detector scanners, decubitus photon counting CT myelography, and intrathecal gadolinium MR myelography. Additional topics to be discussed include optimal patient positioning, respiratory techniques, and intrathecal pressure augmentation.

CT-Guided Epidural Contrast Injection for the Identification of Dural Defects.

Post-dural puncture headache (PDPH) is an increasingly recognized cause of chronic headache. Outside of clinical history and myelography that requires an additional dural puncture, there is no reliable diagnostic test to evaluate for persistent dural defects. We describe the injection of iodinated contrast into the dorsal epidural space under CT guidance in five patients as a potential tool to visualize persistent dural defects.ABBREVIATIONS: PDPH = post-dural puncture headache; SIH = spontaneous intracranial hypotension; DSM = digital subtraction myelography; CTM = CT myelography.

The Magic Number 63 - Redefining the Geriatric Age for Massive Transfusion in Trauma.

INTRODUCTION: The arbitrary geriatric age cutoff of 65 may not accurately define older adults at higher risk of mortality following massive transfusion (MT). We sought to redefine a new geriatric age threshold for MT and understand its association with outcomes. MATERIAL AND METHODS: The 2013-2018 Trauma Quality Improvement Program database was queried for all adults who received ≥10 units of packed red blood cells (pRBCs) within 24 h of admission. A bootstrap analysis using multiple logistic regression established transfusion futility thresholds (TTs), where additional pRBCs no longer improved mortality for various age cutoffs. The age cutoff at which the TT for those relatively older and relatively younger was statistically significant was used to define the new "geriatric" age for MT. Outcomes were then compared between the newly defined geriatric and nongeriatric patients. RESULTS: The difference in TT first became significant when the age cutoff was 63 y. The TT for patients aged ≥63 y (new geriatric, n = 2870) versus <63 y (nongeriatric, n = 17,302) was 34 and 40 units of pRBCs, respectively (P = 0.04). Although geriatric patients had a higher Glasgow coma scale score (9 versus 6, P < 0.01) and lower abbreviated injury score-abdomen (3 versus 4, P < 0.01) than the nongeriatric, they suffered higher overall mortality (62% versus 45%, P < 0.01). A lower percentage of geriatric patients were discharged to home (7% versus 35%, P < 0.01). CONCLUSIONS: The new geriatric age for MT is 63 y, with a TT of 34 units. Despite suffering less severe injuries, physiologically "geriatric" patients have worse outcomes following MT.

Gun violence revictimization in New York State: What increases the risk of being shot again?

BACKGROUND: While gun injuries are more likely to occur in in urban settings and affect people of color, factors associated with gun violence revictimization-suffering multiple incidents of gun violence-are unknown. We examined victim demographics and environmental factors associated with gun violence revictimization in New York state (NYS). METHODS: The 2005-2020 NYS hospital discharge database was queried for patients aged 12-65 years with firearm-related hospital encounters. Patient and environmental variables were extracted. Patient home zip code was used to determine the Social Deprivation Index (SDI) for each patient's area of residence. We conducted bivariate and multivariate analyses among patients who suffered a single incident of gun violence or gun violence revictimization. RESULTS: We identified 38,974 gun violence victims among whom 2,243 (5.8%) suffered revictimization. The proportion of revictimization rose from 4% in 2008 to 8% in 2020 (p < 0.01). The median [IQR] time from first to second incident among those who suffered revictimization was 359 [81-1,167] days. Revictimization was more common among Blacks (75.0% vs 65.1%, p < 0.01), patients with Medicaid (54.9% vs 43.2%, p < 0.01), and in areas of higher deprivation (84.8 percentile vs 82.1 percentile, p < 0.01). CONCLUSIONS: Gun violence revictimization is on the rise. People of color and those residing in areas with high social deprivation are more likely to be re-injured. Our findings emphasize the importance of community-level over individual-level interventions for prevention of gun violence revictimization. LEVEL OF EVIDENCE: Epidemiological, Level III.

Skull Base CSF Leaks: Potential Underlying Pathophysiology and Evaluation of Brain MR Imaging Findings Associated with Spontaneous Intracranial Hypotension.

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) leaks of the skull base and spine share a common process of CSF volume loss, and yet only the latter has been associated with spontaneous intracranial hypotension (SIH). Despite published claims that only spinal leaks cause SIH, no prior studies have evaluated brain MR imaging in patients with skull base leaks for findings associated with SIH such as dural enhancement. The purpose of our study was to use a validated brain MR imaging scoring system to evaluate skull base CSF leak patients for findings associated with SIH. MATERIALS AND METHODS: We included patients with confirmed skull base CSF leaks and contrast enhanced pre-operative brain MRI. The pre-operative MR images were reviewed for findings associated with SIH using the Bern score. Patient age, presenting symptoms and their duration, and leak site were also recorded. RESULTS: 31 patients with skull base CSF leaks were included. Mean Bern score was 0.9 (range 0-4, SD 1.1), and only 1 patient (3%) had dural enhancement. Mean age was 53 years (range 18-76). Mean symptom duration was 1.3 years, with 22 patients presenting within one year of symptom onset. 23 patients (74.2%) had intraoperative confirmation of leak from the middle cranial fossa, involving the temporal bone, while 7 (22.6%) had leaks from the anterior skull base. One patient, who had dural enhancement, had an infratentorial CSF leak along the petrous segment of the internal carotid artery. CONCLUSIONS: Our study provides further evidence that skull base and spinal CSF leaks represent distinct pathophysiologies and present with different brain MRI findings.ABBREVIATIONS: SIH = Spontaneous Intracranial Hypotension; IIH = Idiopathic Intracranial Hypertension.

Radiology-pathology correlation: Giant tumefactive perivascular spaces.

Dilated perivascular spaces (PVSs) are common and easily recognized on imaging. However, rarer giant tumefactive PVSs (GTPVSs) can have unusual multilocular cystic configurations, and are often confused for other pathologic entities, including neoplasms, cystic infarctions, and neuroepithelial cysts. Because GTPVSs are scarcely encountered and even more infrequently operated upon, many radiologists are unaware of the imaging and pathologic features of these lesions. Here, a case of a resected GTPVS is presented, highlighting both its radiologic and histologic characteristics, and discussing how such lesions can be differentiated from their closest mimickers on imaging.

Association between maternal cigarette smoking cessation and risk of preterm birth in Western New York.

BACKGROUND: Although many studies suggested the benefit of smoking cessation among pregnant women in reducing the risk of preterm birth (PTB), the timing of the effect of the cessation remains inconclusive. OBJECTIVES: To examine the association of trimester-specific smoking cessation behaviours with PTB risk. METHODS: We included 199,453 live births in Western New York between 2004 and 2018. Based on self-reported cigarette smoking during preconception and in each trimester, we created six mutually exclusive groups: non-smokers, quitters in each trimester, those who smoked throughout pregnancy, and inconsistent smokers. Risk ratios (RRs) and 95% confidence intervals (CIs) were estimated using Poisson regression to examine the association between smoking cessation and PTB. Effect modification by illegal drug use, maternal age, race and ethnicity and pre-pregnancy body mass index (BMI) was investigated multiplicatively by ratio of relative risk and additively by relative excess risk due to interaction (RERI). RESULTS: Overall, 6.7% of women had a PTB; 14.1% smoked throughout pregnancy and 3.4%, 1.8% and 0.8% reported quitting smoking during the first, second and third trimesters, respectively. Compared to non-smokers, third-trimester cessation (RR 1.20, 95% CI 1.01, 1.43) and smoking throughout pregnancy (RR 1.27, 95% CI 1.21, 1.33) were associated with a higher PTB risk, while quitting smoking during the first or second trimester, or inconsistent smoking was not associated with PTB. A positive additive interaction was identified for maternal age and late smoking cessation or smoking throughout pregnancy on PTB risk (RERI 0.17, 95% CI 0.00, 0.36), and a negative interaction was observed for pre-pregnancy BMI ≥30 kg/m2 (ratio of relative risk 0.70, 95% CI 0.63, 0.78; RERI -0.42, 95% CI -0.56, -0.30). CONCLUSION: Compared to non-smokers, smoking throughout pregnancy and third-trimester smoking cessation are associated with an increased risk of PTB, while quitting before the third trimester may not increase PTB risk.

Evaluation of MR Elastography as a Noninvasive Diagnostic Test for Spontaneous Intracranial Hypotension.

BACKGROUND AND PURPOSE: Spontaneous intracranial hypotension is a condition resulting from a leak of CSF from the spinal canal arising independent of a medical procedure. Spontaneous intracranial hypotension can present with normal brain MR imaging findings and nonspecific symptoms, leading to the underdiagnosis in some patients and unnecessary invasive myelography in others who are found not to have the condition. Given the likelihood that spontaneous intracranial hypotension alters intracranial biomechanics, the goal of this study was to evaluate MR elastography as a potential noninvasive test to diagnose the condition. MATERIALS AND METHODS: We performed MR elastography in 15 patients with confirmed spontaneous intracranial hypotension from September 2022 to April 2023. Age, sex, symptom duration, and brain MR imaging Bern score were collected. MR elastography data were used to compute stiffness and damping ratio maps, and voxelwise modeling was performed to detect clusters of significant differences in mechanical properties between patients with spontaneous intracranial hypotension and healthy control participants. To evaluate diagnostic accuracy, we summarized each examination by 2 spatial pattern scores (one each for stiffness and damping ratio) and evaluated group-wise discrimination by receiver operating characteristic curve analysis. RESULTS: Patients with spontaneous intracranial hypotension exhibited significant differences in both stiffness and damping ratio (false discovery rate-corrected, Q < 0.05). Pattern analysis discriminated patients with spontaneous intracranial hypotension from healthy controls with an area under the curve of 0.97 overall, and the area under the curve was 0.97 in those without MR imaging findings of spontaneous intracranial hypotension. CONCLUSIONS: Results from this pilot study demonstrate MR elastography as a potential imaging biomarker and a noninvasive method for diagnosing spontaneous intracranial hypotension, including patients with normal brain MR imaging findings.

Benefits of Photon-Counting CT Myelography for Localization of Dural Tears in Spontaneous Intracranial Hypotension.

Photon-counting CT is an increasingly used technology with numerous advantages over conventional energy-integrating detector CT. These include superior spatial resolution, high temporal resolution, and inherent spectral imaging capabilities. Recently, photon-counting CT myelography was described as an effective technique for the detection of CSF-venous fistulas, a common cause of spontaneous intracranial hypotension. It is likely that photon-counting CT myelography will also have advantages for the localization of dural tears, a separate type of spontaneous spinal CSF leak that requires different myelographic techniques for accurate localization. To our knowledge, prior studies on photon-counting CT myelography have been limited to techniques for detecting CSF-venous fistulas. In this technical report, we describe our technique and early experience with photon-counting CT myelography for the localization of dural tears.

Intracranial findings in spontaneous intracranial hypotension: Does the severity of abnormalities correspond with certainty and/or multifocality of cerebrospinal fluid leaks?

BACKGROUND AND PURPOSE: Spontaneous intracranial hypotension (SIH) is caused by spinal cerebrospinal fluid (CSF) leaks. This study assessed whether the certainty and/or multifocality of CSF leaks is associated with the severity of intracranial sequelae of SIH. MATERIALS AND METHODS: A retrospective review was completed of patients with suspected SIH that underwent digital subtraction myelogram (DSM) preceded by brain MRI. DSMs were evaluated for the presence or absence of a CSF leak, categorized both as positive/negative/indeterminate and single versus multifocal. Brain MRIs were assessed for intracranial sequelae of SIH based on two probabilistic scoring systems (Dobrocky and Mayo methods). For each system, both an absolute "numerical" score (based on tabulation of findings) and "categorized" score (classification of probability) were tabulated. RESULTS: 174 patients were included; 113 (64.9%) were female, average age 52.0 ± 14.3 years. One or more definite leaks were noted in 76 (43.7%) patients; an indeterminate leak was noted in 22 (12.6%) patients. 16 (16.3%) had multiple leaks. There was no significant difference in the severity of intracranial findings between patients with a single versus multiple leaks (p values ranged from .36 to .70 using categorized scores and 0.22-0.99 for numerical scores). Definite leaks were more likely to have both higher categorized intracranial scores (Mayo p = .0008, Dobrocky p = .006) and numerical scores (p = .0002 for Mayo and p = .006 for Dobrocky). CONCLUSIONS: Certainty of a CSF leak on diagnostic imaging is associated with severity of intracranial sequelae of SIH, with definite leaks having significantly more intracranial findings than indeterminate leaks. Multifocal leaks do not cause greater intracranial abnormalities.

Challenging Dogma by Skipping the Emergency Department Thoracotomy: A Propensity Score Matched Analysis of the Trauma Quality Improvement Database.

INTRODUCTION: Survival following emergency department thoracotomy (EDT) for patients in extremis is poor. Whether intervention in the operating room instead of EDT in select patients could lead to improved outcomes is unknown. We hypothesized that patients who underwent intervention in the operating room would have improved outcomes compared to those who underwent EDT. METHODS: We conducted a retrospective review of the Trauma Quality Improvement Program database from 2017 to 2021. All adult patients who underwent EDT, operating room thoracotomy (ORT), or sternotomy as the first form of surgical intervention within 1 h of arrival were included. Of patients without prehospital cardiac arrest, propensity score matching was utilized to create three comparable groups. The primary outcome was survival. Secondary outcomes included time to procedure. RESULTS: There were 1865 EDT patients, 835 ORT patients, and 456 sternotomy patients who met the inclusion criteria. There were 349 EDT, 344 ORT, and 408 sternotomy patients in the matched analysis. On Cox multivariate regression, there was an increased risk of mortality with EDT versus sternotomy (HR 4.64, P < 0.0001), EDT versus ORT (HR 1.65, P < 0.0001), and ORT versus sternotomy (HR 2.81, P < 0.0001). Time to procedure was shorter with EDT versus sternotomy (22 min versus 34 min, P < 0.0001) and versus ORT (22 min versus 37 min, P < 0.0001). CONCLUSIONS: There was an association between sternotomy and ORT versus EDT and improved mortality. In select patients, operative approaches rather than the traditional EDT could be considered.

High yield clinical applications for photon counting CT in neurovascular imaging.

Photon-counting CT (PCCT) uses a novel X-ray detection mechanism that confers many advantages over that used in traditional energy integrating CT. As PCCT becomes more available, it is important to thoroughly understand its benefits and highest yield areas for improvements in diagnosis of various diseases. Based on our early experience, we have identified several areas of neurovascular imaging in which PCCT shows promise. Here, we describe the benefits in diagnosing arterial and venous diseases in the head, neck, and spine. Specifically, we focus on applications in head and neck CT angiography (CTA), spinal CT angiography, and CT myelography for detection of CSF-venous fistulas. Each of these applications highlights the technological advantages of PCCT in neurovascular imaging. Further understanding of these applications will not only benefit institutions incorporating PCCT into their practices but will also help guide future directions for implementation of PCCT for diagnosing other pathologies in neuroimaging.

Identifying Patients with CSF-Venous Fistula Using Brain MRI: A Deep Learning Approach.

BACKGROUND AND PURPOSE: Spontaneous intracranial hypotension is an increasingly recognized condition. Spontaneous intracranial hypotension is caused by a CSF leak, which is commonly related to a CSF-venous fistula. In patients with spontaneous intracranial hypotension, multiple intracranial abnormalities can be observed on brain MR imaging, including dural enhancement, "brain sag," and pituitary engorgement. This study seeks to create a deep learning model for the accurate diagnosis of CSF-venous fistulas via brain MR imaging. MATERIALS AND METHODS: A review of patients with clinically suspected spontaneous intracranial hypotension who underwent digital subtraction myelogram imaging preceded by brain MR imaging was performed. The patients were categorized as having a definite CSF-venous fistula, no fistula, or indeterminate findings on a digital subtraction myelogram. The data set was split into 5 folds at the patient level and stratified by label. A 5-fold cross-validation was then used to evaluate the reliability of the model. The predictive value of the model to identify patients with a CSF leak was assessed by using the area under the receiver operating characteristic curve for each validation fold. RESULTS: There were 129 patients were included in this study. The median age was 54 years, and 66 (51.2%) had a CSF-venous fistula. In discriminating between positive and negative cases for CSF-venous fistulas, the classifier demonstrated an average area under the receiver operating characteristic curve of 0.8668 with a standard deviation of 0.0254 across the folds. CONCLUSIONS: This study developed a deep learning model that can predict the presence of a spinal CSF-venous fistula based on brain MR imaging in patients with suspected spontaneous intracranial hypotension. However, further model refinement and external validation are necessary before clinical adoption. This research highlights the substantial potential of deep learning in diagnosing CSF-venous fistulas by using brain MR imaging.

Back to the Future: Dynamic Contrast-Enhanced Photon-Counting Detector CT for the Detection of Pituitary Adenoma in Cushing Disease.

Historically, MR imaging has been unable to detect a pituitary adenoma in up to one-half of patients with Cushing disease. This issue is problematic because the standard-of-care treatment is surgical resection, and its success is correlated with finding the tumor on imaging. Photon-counting detector CT is a recent advancement that has multiple benefits over conventional energy-integrating detector CT. We present the use of dynamic contrast-enhanced imaging using photon-counting detector CT for the detection of pituitary adenomas in patients with Cushing disease.

A review of epidural and non-epidural contrast flow patterns during fluoroscopic and CT-guided epidural steroid injections.

Epidural steroid injections are commonly performed using fluoroscopic or CT guidance. With both modalities, the injection of contrast material is necessary before steroid administration to ensure adequate epidural flow and exclude non-epidural flow. While fluoroscopic guidance is conventional, CT is utilized at some centers and can be particularly helpful in the setting of challenging or postoperative anatomy. It is important for proceduralists to be adept at evaluating contrast media flow patterns under both modalities. The goal of this review article is to describe and provide examples of epidural and non-epidural flow patterns on both conventional fluoroscopy and CT. Specific non-epidural patterns discussed include intrathecal flow, intradural/subdural flow, vascular uptake, flow into the retrodural space of Okada, inadvertent facet joint flow, and intradiscal flow.

Transfusion futility thresholds and mortality in geriatric trauma: Does frailty matter?

BACKGROUND: Data on massive transfusion (MT) in geriatric trauma patients is lacking. This study aims to determine geriatric transfusion futility thresholds (TT) and TT variations based on frailty. METHODS: Patients from 2013 to 2018 TQIP database receiving MT were stratified by age and frailty. TTs and outcomes were compared between geriatric and younger adults and among geriatric adults based on frailty status. RESULTS: The TT was lower for geriatric than younger adults (34 vs 39 units; p â€‹= â€‹0.03). There was no difference in TT between the non-frail, frail, and severely frail geriatric adults (37, 30 and 25 units, respectively, p â€‹> â€‹0.05). Geriatric adults had higher mortality than younger adults (63.1% vs 45.8%, p < 0.01). Non-frail geriatric adults had the highest mortality (69.4% vs 56.5% vs 56.2%, p < 0.01). CONCLUSIONS: Geriatric patients have a lower TT than younger adults, irrespective of frailty. This may help improve outcomes and optimize MT utilization.

Cauda equina neuroendocrine tumors: A single institutional imaging review of cases over two decades.

Cauda Equina Neuroendocrine Tumors (CE-NET), previously referred to as paragangliomas are a rare subset of spinal tumors, with limited data on imaging. Herein, we present a retrospective review of clinical and imaging findings of CE-NETs in ten patients who were evaluated at our institution over the past two decades. All patients had well-defined intradural lesions in the lumbar spine which demonstrated slow growth. A review of imaging findings revealed the presence of an eccentric vascular pedicle along the dorsal aspect of the tumor in 8 of the 10 patients (eccentric vessel sign), a distinctive finding that has not previously been reported with this tumor and may help improve the accuracy of imaging-based diagnosis. In all cases, a gross-total resection was performed, with resolution of symptoms in most of the cases.