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Vertebrobasilar junction and basilar trunk aneurysms are extremely difficult to treat, with significant morbidity associated with bypass-trapping procedures. As a result, endovascular techniques including flow diversion and stent-assisted coil embolization have become the mainstay of treatment.1-3 Traditional flow diverters pose risk of occlusion of basilar perforator arteries while traditional stents used as adjuncts for coil-embolization often have high porosity and cannot function as flow diverters. On the other hand, the LVIS stent uniquely provides more porosity than other flow diverters,4,5 allowing patency of perforators while also being amenable to stent-assisted coiling. We present a case of a mixed saccular and fusiform basilar trunk aneurysm that underwent LVIS stent-assisted coil embolization. Using bifemoral access with triaxial systems, one microcatheter was placed in the aneurysm sac and another was used to deploy a stent from the basilar apex into the right vertebral artery. A durable angiographic outcome was observed at 9 months.

Non-contrast head CT (NCCT) is extremely insensitive for early (2 > 0.98). When this 150 CT test set was expanded to include a total of 364 CT scans with a more heterogeneous distribution of infarct locations (94 stroke-negative, 270 stroke-positive mixed territory infarcts), model sensitivity was 97%, specificity 99%, for detection of infarcts larger than the 70 mL volume threshold used for patient selection in several major randomized controlled trials of thrombectomy treatment.

SCA aneurysms are rare, making data on their management sparse compared to other posterior circulation aneurysms. While saccular aneurysms at the SCA origin can be treated with primary coiling or surgical clipping, fusiform and distal SCA aneurysms often require endovascular techniques such as stent-assisted coil embolization or parent vessel occlusion. We present a case of a mixed saccular/fusiform SCA aneurysm that underwent staged stent-assisted coil embolization. A right SCA stent was placed in the first stage. Given the acute angle between the BA and the SCA, microcatheter access and stent placement proved challenging. The decision was made to allow the stent to endothelialize and return in a staged fashion to perform a trans-radial, transcirculatory (trans-left PCoA, trans-left PCA) coil embolization. This provided a straight course between the left P1 segment and the right SCA origin, allowing easy microcatheter navigation through the stent and into the aneurysm for coil embolization.

BackgroundPulsatile tinnitus (PT) can cause significant detriment to quality of life and may herald a life-threatening condition. Endovascular evaluation is the gold standard for the definitive diagnosis of PT and facilitates treatment. However, no large study has determined the distribution of causes and treatment outcomes of PT evaluated endovascularly.MethodsConsecutive patients evaluated at a multidisciplinary PT clinic from a single academic center were retrospectively reviewed. Patients with a suspected cerebrovascular etiology of PT based on clinical and/or non-invasive imaging, who were evaluated by endovascular techniques (arteriography, venography, manometry, and/or balloon test occlusion), were included in analysis. Baseline clinical features and treatment results by final etiology of PT were compared.ResultsOf 552 patients referred for PT evaluation, 164 patients (29.7%) who underwent endovascular evaluation of PT were included. Mean (±SD) age at first clinical evaluation was 54.3±14.1 years (range 25–89 years); 111 patients (67.7%) were female. PT causes were 75.6% vascular and 24.4% non-vascular. Arteriovenous shunting lesions caused 20.7% of cases, venous etiologies 48.2%, and arterial etiologies 6.7%. Of patients with a shunting lesion treated with endovascular embolization, 96.9% had lasting significant improvement or resolution in PT. Endovascular stenting for venous sinus stenosis gave 84.6% of patients lasting improvement or resolution in PT. Arterial and non-vascular PT had fewer patients treated endovascularly and less improvement in PT symptoms.ConclusionPT with a suspected vascular cause is most often attributable to venous etiologies. PT caused by arteriovenous shunting or venous sinus stenosis may be effectively treated endovascularly.

BackgroundPediatric spinal arteriovenous shunts (SAVS) are rare lesions with heterogeneous pathogenesis and clinical manifestations.ObjectiveTo evaluate the clinical characteristics, angioarchitecture, and technical/clinical outcomes in SAVS through a large single-center cohort analysis and meta-analysis of individual patient data.MethodsA retrospective institutional database identified children (aged 0–21 years) who underwent digital subtraction spinal angiography (DSA) for SAVS between January 1996 and July 2021. Clinical data were recorded to evaluate angioarchitecture, generate modified Aminoff-Logue gait disturbance scores (AL) and McCormick grades (MC), and assess outcomes. We then performed a systematic literature review following PRISMA-IPD (Preferred Reporting Items for Systematic Reviews and Meta-Analyses for individual patient data) guidelines, extracting similar data on individual patients for meta-analysis.ResultsThe cohort consisted of 28 children (M:F=11:17) with 32 SAVS lesions, with a mean age of 12.8±1.1 years at diagnosis. At presentation, SAVS were most highly concentrated in the cervical region (40.6%). Children had a median AL=2 and MC=2, with thoracolumbar AVS carrying the greatest disability. Among treated cases, complete obliteration was achieved in 48% of cases and median AL scores and MC grades both improved by one point. Systematic literature review identified 161 children (M:F=96:65) with 166 SAVS lesions with a mean age of 8.7±0.4 years. Among studies describing symptom chronicity, 37/51 (72.5%) of children presented acutely. At presentation, children had a median AL=4 and MC=3, with thoracolumbar AVS carrying the highest MC grades. After intervention, median AL and MC both improved by one point.ConclusionsThis study provides epidemiologic information on the location, onset, and presentation of the full spectrum of pediatric SAVS, highlighting the role of targeted treatment of high-risk features.

Methamphetamine (MA) use is associated with poor outcomes after aneurysmal subarachnoid hemorrhage (aSAH). MA exerts both hemodynamic and inflammatory effects, but whether these manifest with altered intracranial aneurysm (IA) remodeling is unknown. The objective of this study was to compare IA geometric and morphologic features in patients with and without MA detected on urine toxicology (Utox) at presentation.We retrospectively reviewed 160 consecutive patients with SAH and Utox at time of admission. Geometric-morphologic IA characteristics were assessed by blinded neuroradiologists. Studied features were maximum sac diameter, location, size, ellipsoid volume, aspect ratio, size ratio, volume: neck ratio, dome: neck ratio, bottleneck factor, morphology (saccular, fusiform/dissecting, blister, mycotic), and presence of bleb, vasculopathy, or additional unruptured IA.Of 139/160 patients with aSAH, 23/139 (16.5%) were Utox MA+. There was no difference in aneurysm subtype frequency, presence of bleb, vasculopathy, or presence of an additional (unruptured) aneurysm with a trend toward posterior circulation location and higher Hunt and Hess grade (P = 0.09 for both) in the MA+ group. Maximum IA sac diameter, ellipsoid volume, dome-neck ratio, and size ratio were similar between groups. Only the aspect ratio (AR) differed between groups (MA+ = 2.20 vs. MA- = 1.74, P = 0.02). The AR remained a significant predictor of Utox MA+ in a multiple logistic regression analysis (odds ratio 1.87, 95% confidence interval 1.06-3.39).Active use of methamphetamine is independently associated with larger AR in patients with ruptured IA. This may indicate hazardous remodeling due to hemodynamic and/or inflammatory changes.

Acute hemorrhage in the head and neck (AHNH) is life-threatening due to asphyxiation and hemorrhagic shock. When conservative measures fail, some patients benefit from endovascular therapy (EVT). While CTA is routinely used to localize bleeding and plan EVT in gastrointestinal hemorrhage, the diagnostic value of CTA in AHNH and role of CTA in treatment-planning are uncertain. We retrospectively reviewed neck CTAs from June 2015 to October 2018 indicated for AHNH. When performed, digital subtraction angiography (DSA) findings and EVT were documented. Extravasation or pseudoaneurysm on DSA was considered positive for bleed localization. Thirty CTA exams were performed for AHNH in 18 patients (mean age = 56.6, male% = 55.6%). Eleven out of 30 exams (36.7%) had immediate DSA follow-up within 24 h. Etiologies of hemorrhage included malignancy 11/18 (61.1%) and coagulopathy (4/18, 22.2%) among others. CTA reports identified definite or possible source of bleeding in 7/30 (23.3%) exams. Seven out of 7 (100%) patients with definite or possible source of bleeding on CTA underwent DSA and 4/23 (17.4%) patients underwent DSA despite negative CTA. With DSA as the gold standard, CTA had a sensitivity of 70% and a specificity of 100%. CTA has high specificity and reasonable sensitivity for detecting arterial source of bleeding in patients presenting with AHNH. Patients with negative CTA may avoid catheter angiography in most cases; however, false-negative CTA should not preclude angiography in high-risk patients.

Three-dimensional cinematic rendering (3DCR) is an emerging postprocessing technique for computed tomography (CT) and CT angiography (CTA) that produces photorealistic, volumetric images. In contrast to conventional volume rendering techniques, 3DCR depicts life-like shadowing and surface reflection, which can improve the perception of depth and complex anatomic spatial relationships. This tool allows clinical neuroimagers to study, explore, and teach the complex relational anatomy of the cerebral vessels and skull in a more intuitive manner. The purpose of this report is to introduce the physical and optical principles behind 3DCR and to explore applications of 3DCR in modern cerebrovascular imaging. Using CTA source data, we describe our approach to visualizing cerebrovascular anatomy and disease and introduce three simple, reproducible techniques through a series of case vignettes. First, we show how selective manipulation of rendered models can imitate cadaveric dissection. Next, we discuss surface rendering as a means of recapitulating the neurologic physical exam. Last, we provide a step-by-step method of simulating the operating room perspective in visualizing cerebrovascular disease. In our experience, 3DCR proves most useful for visualizing structures at the vessel-skull interface, which can be difficult to assess with conventional imaging methods. 3DCR, therefore, complements traditional 2-dimensional and 3-dimensional imaging methods and serves as an emerging tool for neuroimagers to communicate with and educate other clinicians.

The pharyngo-tympano-stapedial middle meningeal artery (PTS-MMA) variant has been described in one case report and never in the setting of arterial supply to a dural arteriovenous fistula, to our knowledge. We report the case of a middle-aged patient with severe, daily headache who presented to our institution for angiography and treatment. CT angiography and MRI demonstrated an enlarged left middle meningeal artery coursing to a large venous varix in the falcotentorial region. Dural arteriovenous fistula was confirmed by subsequent cerebral angiography. Endovascular treatment was performed but without complete obliteration of the fistula. Follow-up angiography demonstrated parasitized arterial supply from a right middle meningeal artery arising from the proximal cervical internal carotid artery coursing through the middle ear consistent with a PTS-MMA variant. The fistula was then treated surgically without recurrence at the 6-month follow-up.

Background Giant cell arteritis (GCA) is a systemic vasculitis that may cause ischemic stroke. Rarely, GCA can present with aggressive intracranial stenoses, which are refractory to medical therapy. Endovascular treatment (EVT) is a possible rescue strategy to prevent ischemic complications in intracranial GCA but the safety and efficacy of EVT in this setting are not well-described. Methods A systematic literature review was performed to identify case reports and series with individual patient-level data describing EVT for intracranial GCA. The clinical course, therapeutic considerations, and technique of seven endovascular treatments in a single patient from the authors’ experience are presented. Results The literature review identified 9 reports of 19 treatments, including percutaneous transluminal angioplasty (PTA) with or without stenting, in 14 patients (mean age 69.6 ± 6.3 years). Out of 12 patients 8 (66.7%) with sufficient data had > 1 pre-existing cardiovascular risk factor. All patients had infarction on MRI while on glucocorticoids and 7/14 (50%) progressed despite adjuvant immunosuppressive agents. Treatment was PTA alone in 15/19 (78.9%) cases and PTA + stent in 4/19 (21.1%). Repeat treatments were performed in 4/14 (28.6%) of patients (PTA-only). Non-flow limiting dissection was reported in 2/19 (10.5%) of treatments. The indications, technical details, and results of PTA are discussed in a single illustrative case. We report the novel use of intra-arterial calcium channel blocker infusion (verapamil) as adjuvant to PTA and as monotherapy, resulting in immediate improvement in cerebral blood flow. Conclusion Endovascular treatment, including PTA with or without stenting or calcium channel blocker infusion, may be effective therapies in medically refractory GCA with intracranial stenosis.

Purpose Brain herniation into arachnoid granulations (BHAG) of the dural venous sinuses is a recently described finding of uncertain etiology. The purpose of this study was to investigate the prevalence of BHAG in a cohort of patients with pulsatile tinnitus (PT) and to clarify the physiologic and clinical implications of these lesions. Methods The imaging and charts of consecutive PT patients were retrospectively reviewed. All patients were examined with MRI including pre- and post-contrast T1- and T2-weighted sequences. Images were reviewed separately by three blinded neuroradiologists to identify the presence of BHAG. Their location, signal intensity, size, presence of arachnoid granulation, and associated dural venous sinus stenosis were documented. Clinical records were further reviewed for idiopathic intracranial hypertension, history of prior lumbar puncture, and opening pressure. Results Two hundred sixty-two consecutive PT patients over a 4-year period met inclusion criteria. PT patients with BHAG were significantly more likely to have idiopathic intracranial hypertension than PT patients without BHAG (OR 4.2, CI 1.5–12, p = 0.006). Sixteen out of 262 (6%) patients were found to have 18 BHAG. Eleven out of 16 (69%) patients had unilateral temporal or occipital lobe herniations located in the transverse sinus or the transverse-sigmoid junction. Three out of 16 (19%) patients had unilateral cerebellar herniations and 2/16 (13%) patients had bilateral BHAG. Conclusion In patients with PT, BHAG is a prevalent MRI finding that is strongly associated with the clinical diagnosis of IIH. The pathogenesis of BHAG remains uncertain, but recognition should prompt comprehensive evaluation for IIH.

BackgroundPercutaneous sclerotherapy is an effective treatment for lymphatic malformations (LM) of the head and neck in adults. The purpose of this study was to examine the indications and efficacy of sclerotherapy for head/neck LM in the neonate and infant population.MethodsWe retrospectively reviewed patients treated with percutaneous sclerotherapy for LM of the head/neck at age ≤12 months at a single vascular anomalies clinic. The clinical, anatomic, and technical aspects of each treatment, complications, and post-treatment clinical and imaging outcomes were analyzed.Results22 patients underwent 36 treatments during the first year of life. Median age at first treatment was 6.2 months (range 2–320 days). Severe airway compromise was the most frequent indication for treatment (31.8%). Sclerosants included doxycycline (80.5%), sodium tetradecyl sulfate (55.5%), bleomycin (11.1%) and ethanol (2.8%). There were no immediate procedure-related complications; sclerosant-related laboratory complications included transient metabolic acidosis (8.3%) and hemolytic anemia (5.5%). Median follow-up was 3.7 years (IQR 0.6–4.8). 47.6% of patients showed >75% lesion size reduction and 19.0% showed minimal response (ConclusionsPercutaneous sclerotherapy is a safe and effective treatment for symptomatic LM of the head and neck in neonates and infants. Treatment strategy and management of recurrent symptoms requires consensus from an experienced, multidisciplinary team.

The simultaneous growth of robotic-assisted surgery and telemedicine in recent years has only been accelerated by the recent coronavirus disease 2019 pandemic. Robotic assistance for neurovascular intervention has garnered significant interest due to opportunities for tele-stroke models of care for remote underserved areas. Lessons learned from medical robots in interventional cardiology and neurosurgery have contributed to incremental but vital advances in medical robotics despite important limitations. In this article, we discuss robot types and their clinical justification and ethics, as well as a general overview on available robots in thoracic/abdominal surgery, neurosurgery, and cardiac electrophysiology. We conclude with current clinical research in neuroendovascular intervention and a perspective on future directions.

Although enthusiasm for transradial access for neurointerventional procedures has grown, a unique set of considerations bear emphasis to preserve safety and minimize complications. In the first part of this review series, we will review important anatomical considerations for safe and easy neuroendovascular procedures from a transradial approach. These include normal and variant radial artery anatomy, the anatomic snuffbox, as well as axillary, brachial, and great vessel arterial anatomy that is imperative for the neuroendovascular surgeon to be intimately familiar prior to pursuing transradial access procedures. In the next part of the review series, we will focus on safety and complications specific to a transradial approach.

Large, wide-necked basilar apex aneurysms are difficult to treat. Microsurgical clipping can result in neurologic morbidity and mortality. Endovascular treatment often leaves remnants that need retreatment and/or stent placement with dual antiplatelet therapy. The Woven EndoBridge (WEB) is an intrasaccular flow disruption device that can be used without dual antiplatelet therapy. However, the WEB cannot typically be used in large or giant aneurysms > 10 mm because the largest diameter device is the 11 × 9.6 mm single layer sphere (SLS). We present a case in which we use a PulseRider aneurysm neck reconstruction device in the basilar artery to assist in WEB deployment within a 22 mm basilar apex aneurysm with 14 mm neck, thereby permitting aspirin monotherapy postoperatively.

The purpose of this study was to demonstrate the ability of a custom window blending algorithm to depict multicompartmental disease processes of the maxillofacial region in a single image, using routine computed tomography (CT) DICOM data. Five cases were selected from case files demonstrating trauma, infection, and malignancy of the maxillofacial region on routine CT examinations. Images were processed with a modified Relative Attenuation-Dependent Image Overlay (RADIO) window-blending algorithm in Adobe Photoshop controlled by ExtendScript. The modified RADIO algorithm was able to demonstrate pertinent multicompartmental imaging findings in each of the examinations, allowing simultaneous visualization of clinically relevant bone and soft tissue findings in a single image, without needing to change window and level settings. A custom window blending algorithm can demonstrate a range of multicompartmental pathology in the maxillofacial region in a single image.

Percutaneous sclerotherapy is an effective technique for treating lymphatic malformations of the head and neck, with clinical success rates exceeding 84%.1 Sodium tetradecyl, which damages lipid membranes and stimulates free radical-induced local damage, and doxycycline, which inhibits angiogenesis, have emerged as the safest and most effective of several available sclerosants.2–4 Although severe periprocedural morbidity is rare, temporary local complications are reported in 14% and skin necrosis or scarring in up to 0.8–5.8% of sclerotherapy procedures.5 As these lesions are frequently located in the face and/or neck, even minor complications can be disfiguring and must be avoided. This technical video describes a ‘dual-agent’ approach for percutaneous sclerotherapy of macrocystic lymphatic malformations using sodium tetradecyl as a ‘primer’ followed by doxycycline as a definitive sclerosant (video 1). This technique emphasizes meticulous backtable preparation and effective use of ultrasound and fluoroscopy to minimize complications.Video 1

Although enthusiasm for transradial access for neurointerventional procedures has grown, a unique set of considerations bear emphasis to preserve safety and minimize complications. In the first part of this review series, we reviewed anatomical considerations for safe and easy neuroendovascular procedures from a transradial approach. In this second part of the review series, we aim to (1) summarize evidence for safety of the transradial approach, and (2) explain complications and their management.

Background Stent-assisted coil embolization of wide-necked bifurcation aneurysms often employs a Y configuration stent. A similar stent configuration, termed kissing/double-barrel (KDB), is used often at the aortoiliac bifurcation. Studies of KDB stents in aortoiliac disease show that rates of thromboembolic complications vary with the cross-sectional geometry of the stent pair, a function of the radial crush resistive force of each stent. We assessed cross-sectional geometry of intracranial stent pairs in an in vitro model of the basilar artery using flat-panel computed tomography. Methods In a silicone model of a wide-necked basilar tip aneurysm, 6 simulated KDB stent deployment trials were performed using combinations of 5 stents (Enterprise 1, Enterprise 2, Neuroform Atlas, LVIS, LVIS Jr.). Flat-panel computed tomography reconstructions were used to assess cross-sectional stent geometry. Relative conformability, defined by ovalization and D-ratio, radial crush resistive force (predicted vs. actual), and radial mismatch fraction were compared by stent type (braided vs. laser-cut). Results Several distinct forms of cross-sectional stent geometry were observed. Braided stents had lower ovalization and D-ratio (P = 0.015) than laser-cut stents. The Neuroform Atlas/LVIS combination yielded the lowest radial mismatch fraction (19.7% vs. mean 44.3% ± 0.7%). Braided stents tended to have a deployed stent radius closer to the expected (nominal) diameter (i.e., higher relative crush resistive force) than laser-cut stents (measured vs. nominal diameter discrepancy +38.6% ± 21.1% vs. –10.7% ±16.1%, P = 0.14). Conclusions In constant anatomy, cross-sectional geometry of the KDB stent configuration will vary depending on the design and structure of the stents employed.

BACKGROUNDThe authors recently reported a series of children with vertebral artery (VA) compression during head turning who presented with recurrent posterior circulation stroke. Whether VA compression occurs during head positioning for cranial surgery is unknown.OBSERVATIONSThe authors report a case of a child with incidental rotational occlusion of the VA observed during surgical head positioning for treatment of an intracranial arteriovenous fistula. Intraoperative angiography showed dynamic V3 occlusion at the level of C2 with distal reconstitution via a muscular branch “jump” collateral, supplying reduced flow to the V4 segment. She had no clinical history or imaging suggesting acute or prior stroke. Sequential postoperative magnetic resonance imaging scans demonstrated signal abnormality of the left rectus capitus muscle, suggesting ischemic edema.LESSONSThis report demonstrates that rotational VA compression during neurosurgical head positioning can occur in children but may be asymptomatic due to the presence of muscular VA–VA “jump” collaterals and contralateral VA flow. Although unilateral VA compression may be tolerated by children with codominant VAs, diligence when rotating the head away from a dominant VA is prudent during patient positioning to avoid posterior circulation ischemia or thromboembolism.

Background and Purpose: Do children have an increased risk for brain arteriovenous malformation (AVM) recurrence compared with adults and does this risk vary depending on initial presentation with AVM rupture? Methods: We retrospectively studied 115 patients initially presenting with brain AVM under age 25 years who underwent complete surgical resection of the AVM as documented by digital subtraction angiography (DSA) and had delayed follow-up DSA to evaluate for AVM recurrence after apparent initial cure. Results: The mean time from baseline DSA to follow-up DSA was 2.3 years, ranging from 0 to 15 years. Twelve patients (10.4% of the 115 patient cohort and 16.7% of 72 patients with hemorrhage at initial presentation) demonstrated AVM recurrence on follow-up DSA. All patients with recurrence initially presented with intracranial hemorrhage, and intracranial hemorrhage was a significant predictor of recurrence (log rank P =0.037). Among patients with initial hemorrhage, the 5-year recurrence rate was 17.8% (95% CI, 8.3%–35.7%). All recurrences occurred in patients who were children at the time of their initial presentation; the oldest was 15 years of age at the time of initial AVM surgery. The 5-year recurrence rate for children (0–18 years of age) with an initial presentation of hemorrhage was 21.4% (95% CI, 10.1%–41.9%). Using Cox regression, we found the risk of AVM recurrence decreased by 14% per each year increase in age at the time of initial surgical resection (hazard ratio=0.86 [95% CI, 0.75–0.99]; P =0.031). Conclusions: There is a high rate of recurrence of apparently cured brain AVMs in children who initially present with AVM rupture. Imaging follow-up is warranted to prevent re-rupture.

Dural arteriovenous fistulas (DAVFs) are high-flow acquired shunts that can carry high risk of intracranial hemorrhage. Because DAVFs can often be managed by endovascular means, early and accurate diagnosis can markedly improve patient morbidity. Time-of-flight and arterial spin-labeling MRA have increased the diagnostic utility of MRI for DAVF by showing hemodynamic rather than anatomic evidence of shunting. The purpose of this article is to describe the cases of seven patients who had co-localization of arterial spin-labeling signal intensity and time-of-flight flow-related enhancement in the left skull base, resulting in a misdiagnosis of DAVF and a recommendation for catheter angiography by the interpreting radiologist. Benign jugular venous reflux is identified as a common mechanism in each case, and the physiology behind this imaging pitfall is described. An algorithmic diagnostic approach to differentiating physiologic venous reflux from true posterior skull base DAVFs is presented.

Artificial or augmented intelligence, machine learning, and deep learning will be an increasingly important part of clinical practice for the next generation of radiologists. It is therefore critical that radiology residents develop a practical understanding of deep learning in medical imaging. Certain aspects of deep learning are not intuitive and may be better understood through hands-on experience; however, the technical requirements for setting up a programming and computing environment for deep learning can pose a high barrier to entry for individuals with limited experience in computer programming and limited access to GPU-accelerated computing. To address these concerns, we implemented an introductory module for deep learning in medical imaging within a self-contained, web-hosted development environment. Our initial experience established the feasibility of guiding radiology trainees through the module within a 45-min period typical of educational conferences.

Reporting efficiency is commonly used to measure performance and quality in diagnostic imaging. For academic centers, balancing the clinical demand for efficient reporting and educational obligation to trainees remains a major challenge. The objective of this study was to quantify the effect of trainee education on reporting efficiency over the academic year (July to June) for a single diagnostic imaging examination type.The authors reviewed a 10-year data set of lumbar spinal MRI reports and time-stamp data and compared change in mean reporting time for trainee versus attending radiologist-only reports. Odds ratios, linear regression, and correlation analysis were performed to evaluate relationships of mean and cumulative reporting times, volume, and study month.Mean reporting time for the trainee group peaked in July (287.2 ± 4.9 min). The largest month-to-month increase was from June to July (+46.3 min, P.01) for the trainees, and July showed the largest deviation from annualized mean reporting time (odds ratio, 1.31; 95% confidence interval, 1.16-1.47; P.001). Mean reporting time improved linearly over the course of the academic year from July to June for trainees (RThis study quantifies the effect of trainee education on reporting efficiency and models the operational "learning curve" of improved performance over the academic year. These data may inform staffing and workflow improvement efforts in academic radiology departments.

Acute hemorrhage in the head and neck (AHNH) is life-threatening due to asphyxiation and hemorrhagic shock. When conservative measures fail, some patients benefit from endovascular therapy (EVT). While CTA is routinely used to localize bleeding and plan EVT in gastrointestinal hemorrhage, the diagnostic value of CTA in AHNH and role of CTA in treatment-planning are uncertain.We retrospectively reviewed neck CTAs from June 2015 to October 2018 indicated for AHNH. When performed, digital subtraction angiography (DSA) findings and EVT were documented. Extravasation or pseudoaneurysm on DSA was considered positive for bleed localization.Thirty CTA exams were performed for AHNH in 18 patients (mean age = 56.6, male% = 55.6%). Eleven out of 30 exams (36.7%) had immediate DSA follow-up within 24 h. Etiologies of hemorrhage included malignancy 11/18 (61.1%) and coagulopathy (4/18, 22.2%) among others. CTA reports identified definite or possible source of bleeding in 7/30 (23.3%) exams. Seven out of 7 (100%) patients with definite or possible source of bleeding on CTA underwent DSA and 4/23 (17.4%) patients underwent DSA despite negative CTA. With DSA as the gold standard, CTA had a sensitivity of 70% and a specificity of 100%.CTA has high specificity and reasonable sensitivity for detecting arterial source of bleeding in patients presenting with AHNH. Patients with negative CTA may avoid catheter angiography in most cases; however, false-negative CTA should not preclude angiography in high-risk patients.

Metastatic gastroenteropancreatic neuroendocrine neoplasms (mGEP-NEN) are indolent malignancies which undergo frequent imaging follow-up. Hepatocellular phase (HCP) MR with hepatocellular-specific contrast agent is widely used to evaluate mGEP-NEN liver metastases but is commonly performed after a 20-min delay which prolongs scan time. The purpose of this study was to evaluate if HCP MR at 15 min offers comparable performance to 20-min delay for patients with mGEP-NEN undergoing routine imaging surveillance. In this IRB-approved retrospective study, we evaluated 52 patients with mGEP-NEN who were imaged for routine surveillance with gadoxetate disodium (Eovist®)-enhanced MR including 15- and 20-min delayed HCP. Two readers (R1, R2), blinded to HCP timing, independently reviewed each set of images in random order at least 1 month apart. Readers assessed presence and conspicuity of metastases, and subjective image quality using 5-point scales. Readers quantified the number of metastases and diameter of the largest lesion. Statistical analysis was performed to determine individual-reader and inter-reader differences for qualitative and quantitative data. No differences were observed for subjective image quality (R1 p = 0.86, R2 p = 0.17) or lesion conspicuity (R1 p = 0.56, R2 p = 0.74) at 15 min and 20 min for either reader. Individual-reader concordance correlation coefficient between 15 and 20 min was high for number of metastases detected (R1 = 0.9842, R2 = 0.9579) and diameter of largest metastasis (R1 = 0.9629, R2 = 0.8859). HCP imaging at 15 min provides similar diagnostic yield to standard 20-min delay, which may help reduce the scan time and costs, and improve throughput and patient satisfaction.

Artificial intelligence and machine learning (AI-ML) have taken center stage in medical imaging. To develop as leaders in AI-ML, radiology residents may seek a formative data science experience. The authors piloted an elective Data Science Pathway (DSP) for 4th-year residents at the authors' institution in collaboration with the MGH & BWH Center for Clinical Data Science (CCDS). The goal of the DSP was to provide an introduction to AI-ML through a flexible schedule of educational, experiential, and research activities. The study describes the initial experience with the DSP tailored to the AI-ML interests of three senior radiology residents. The authors also discuss logistics and curricular design with common core elements and shared mentorship. Residents were provided dedicated, full-time immersion into the CCDS work environment. In the initial DSP pilot, residents were successfully integrated into AI-ML projects at CCDS. Residents were exposed to all aspects of AI-ML application development, including data curation, model design, quality control, and clinical testing. Core concepts in AI-ML were taught through didactic sessions and daily collaboration with data scientists and other staff. Work during the pilot period led to 12 accepted abstracts for presentation at national meetings. The DSP is a feasible, well-rounded introductory experience in AI-ML for senior radiology residents. Residents contributed to model and tool development at multiple stages and were academically productive. Feedback from the pilot resulted in establishment of a formal AI-ML curriculum for future residents. The described logistical, planning, and curricular considerations provide a framework for DSP implementation at other institutions. Supplemental material is available for this article. © RSNA, 2020.

Infected (mycotic) intracranial aneurysms (IIA) are a prevalent source of morbidity in patients with systemic infection. Unlike saccular aneurysms, ruptured IIA frequently presents with intracerebral hemorrhage (ICH), and the appearance of ruptured IIA on CTA overlaps with the CTA “Spot Sign” (SS), an imaging finding in non-infectious, spontaneous ICH. The purpose of this study was to investigate the imaging and clinical features which may differentiate these two entities on CTA for which treatment strategies differ substantially. In an IRB-approved, retrospective case series, we compared 14 patients with confirmed IIA and 14 patients with positive SS due to other non-infectious etiology (SS(+) ICH). Clinical history, laboratory studies, and CTA reports and images were reviewed to define imaging characteristics of IIA and SS(+) ICH, including the diagnostic criteria for SS used in clinical trials. A total of 7/14 patients (50.0%) diagnosed with IIA had ICH at presentation. Of these, 3/7 patients (42.9%) with ruptured IIA and ICH met diagnostic imaging criteria of SS. The remaining 4/7 patients did not meet criteria due to presence of a connecting vessel. Compared with SS(+) ICH of non-infectious etiology, patients with ruptured IIA were younger (40.7 vs. 66.4 years) and had higher rates of IVDU and bacteremia (p

Background The American College of Radiology Imaging 3.0 paradigm emphasizes the need for radiologists to serve as imaging consultants to their referring colleagues. However, outside the reading room, teaching interactions between radiology and nonradiology residents are limited. Internal Medicine Morning Report (IMMR) is a resident-run educational program widely employed by internal medicine (IM) residencies. Although medical imaging is regularly discussed in IMMR, radiology residents are not typically involved in case preparation. We aimed to develop a peer-to-peer imaging teaching consultation service (TCS) incorporated into the well-established structure of IMMR. By creating illustrative, “dynamic” teaching slides for use at these conferences, we sought to provide salient radiology teaching material, demystify jargon, discuss appropriate imaging use, and review relevant anatomy. We hypothesized that TCS could improve the quality of IMMR as perceived by the IM presenter. Methods TCS was piloted over a 7-month period. Each referred case was reviewed by a senior radiology resident who produced a set of “dynamic” teaching slides for each case. These included patient imaging overlayed with extensive annotations and animations highlighting teaching points, with particular attention to radiologic terminology. Slides were shared with the IM presenter, who could use them for preparation and include the animations in the talk if desired. TCS effectiveness was evaluated with a survey distributed to participating IM residents. Results In the pilot period, 12 TCS requests were received and 10 were performed in collaboration with 6 IM residents. Survey results indicated that most IM residents did not consult radiologists prior to TCS (5/6, 83%). IM residents used the “dynamic” teaching slides to both prepare for and present at IMMR (5/6, 83%). TCS improved IM residents’ perceived ability to engage their audience (6/6, 100%), confidence in teaching radiology material (4/6, 67%), ability to understand radiology reports (4/6, 67%) and appreciation for what radiologists do (6/6, 100%). Conclusions The TCS pilot resulted in successful radiology-IM collaboration and improved knowledge and confidence in teaching imaging concepts. Continuous program evaluation will be performed and future work will assess the effect of TCS on radiologist confidence in real-world clinical consultations.