Long-Term Safety and Efficacy of Pipeline Embolization Device in Anterior and Posterior Circulation Aneurysms: A Systematic Review and Meta-Analysis.

BACKGROUND: Flow diversion using the pipeline embolization device (PED) has been a paradigm shift for anterior circulation (AC) aneurysms. However, only a few studies report the long-term (≥1 year) angiographic and clinical outcomes for posterior circulation (PC) aneurysms. This study aims to compare the long-term safety and efficacy of treatment of AC and PC aneurysms with PED. METHODS: The databases included Ovid MEDLINE, Ovid EMBASE, Ovid Cochrane, and Scopus. Studies with at least 10 patients and 1-year follow-up were included. Twenty-four studies met our inclusion criteria. A random effect meta-analysis was performed to estimate the ischemic and hemorrhagic complications. A meta-analysis of proportions was performed to estimate the pooled rates of long-term complete aneurysmal occlusion, symptomatic stroke, aneurysmal rupture, and intracranial hemorrhage. RESULTS: There were 1952 aneurysms, of which 1547 (79.25%) were in the AC and 405 (20.75%) in the PC. The 1-year occlusion rate was 78% in AC compared to 73% in PC aneurysms (P < 0.01). The symptomatic infarct rate was 5% in AC compared to 13% in PC (P < 0.01). While the rupture rate was 1% in AC compared to 4% in PC (P = 0.01), the rate of intracranial hemorrhage was 2% for both (P = 0.99). CONCLUSIONS: The long-term occlusion rate after PED was higher in AC aneurysms, and the cumulative incidence of stroke and aneurysm rupture was higher in PC aneurysms.

Imaging 3.0: A scoping review.

We aim to provide a comprehensive summary of the current body of literature concerning the Imaging 3.0 initiative and its implications for patient care within the field of radiology. We offer a thorough analysis of the literature pertaining to the Imaging 3.0 initiative, emphasizing the practical application of the five pillars of the program, their cost-effectiveness, and their benefits in patient management. By doing so, we hope to illustrate the impact the Imaging 3.0 Initiative can have on the future of radiology and patient care.

A secondary daily persistent headache from onset with underlying nutcracker physiology and spinal epidural venous congestion: case series with lumbar vein embolization as a therapeutic approach.

The authors have published on a unique subset of patients whose headaches worsened in the Trendelenburg position and who on time-resolved MR angiography demonstrated left renal vein compression (nutcracker physiology) with retrograde left second lumbar vein (L2LV) flow and regional spinal epidural venous plexus (EVP) congestion. We hypothesized that the spinal EVP congestion subsequently causes a secondary congestion of the cerebral venous system, which then leads to an elevation of CSF pressure above that individuals CSF pressure set point. This results in a daily headache from onset. Thus, eliminating the spinal EVP could conceivably improve or eliminate the manifested headache syndrome. We now present a case series of four patients with long-term follow-up utilizing lumbar vein coil embolization as a new therapeutic approach. In each patient, the MR angiography findings were verified by catheter-based venography. Treatment consisted of endovascular embolization of the second lumbar vein. Four patients have had coil embolization of which three are 1 year or longer from their procedure while one is 10 months posttreatment. All patients were women. Duration of daily headache prior to embolization ranged from 4 to 8 years. Post-embolization: Three patients are either headache free or 90-95% improved with substantial pain free time. There were no procedure-related complications. Our results suggest that embolization of L2LV in a specific patient population with nutcracker physiology may substantially improve head pain issues. This is a minimally invasive outpatient technique with no apparent side effects.

A Scoping Review of Simulation-Based Training Paradigms for Carotid Artery Endarterectomy and Carotid Artery Stenting.

BACKGROUND: Surgical simulation has come to the forefront to enhance the training of residents. The aim of our scoping review is to analyze the available simulation-based carotid revascularization techniques, including carotid endarterectomy (CEA) and carotid artery stenting (CAS) and suggest critical steps for evaluating competency in a standardized fashion. METHODS: A scoping review of all reports on simulation-based carotid revascularization techniques including CEA and CAS was performed in PubMed/MEDLINE, Scopus, Embase, Cochrane, Science Citation Index Expanded, Emerging Sources Citation Index, and Epistemonikos databases. Data were collected according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The English language literature was searched from January 1, 2000 to January 9, 2022. The outcomes evaluated included measures of assessment of operator performance. RESULTS: Five CEA and 11 CAS manuscripts were included in this review. The methods of assessments employed by these studies to judge performance were comparable. The 5 CEA studies sought to validate and demonstrate improved performance with training or distinguish surgeons by their experience level, either through assessing operative performance or end-product results. The 11 CAS studies used 1 of 2 types of commercial simulators and focused on determining the efficacy of simulators as teaching tools. By examining the steps of the procedure associated with preventable perioperative complications, it provides a reasonable framework for determining which elements of the procedure should be emphasized most. Furthermore, using potential errors as a basis for assessment of competency could reliably distinguish operators based on level of experience. CONCLUSIONS: Competency-based simulation training is becoming more relevant as our surgical training paradigm shifts with the increased scrutiny within training programs of work-hour regulations and the need to develop a curriculum to assess our trainees' ability to perform specific operations competently during their stipulated training period. Our review has given us an insight into the current efforts in this space regarding 2 specific procedures that are key for all vascular surgeons to master. Although many competency-based modules are available, there is a lack of standardization in the grading/rating system of what surgeons consider vital steps of each procedure to assess these simulation-based modules. Therefore, the next steps of curriculum development should be based on standardization efforts for the different protocols available.

Systematic Review on Magnetic Resonance Angiography with Vessel Wall Imaging for the Characterization of Symptomatic Carotid Artery Plaque.

BACKGROUND: To perform a systematic literature review to assess the usefulness of performing magnetic resonance angiography (MRA) with vessel wall imaging (VWI) sequences for the assessment of symptomatic carotid artery plaques and the identification of risky plaque features predisposing for stroke. METHODS: We performed a systematic review of the literature pertaining to MRA with VWI techniques in patients with carotid artery disease, focusing on symptomatic patients' plaque features and morphology. Independent reviewers screened and analyzed data extracted from eligible studies, and a modified Newcastle-Ottawa Scale was used to appraise the quality of the design and content of the selected manuscripts to achieve an accurate interpretation. RESULTS: This review included nineteen peer-reviewed manuscripts, all of them including MRA and VWI assessments of the symptomatic carotid artery plaque. We focused on patients' comorbidities and reviewed plaque features, including intraplaque hemorrhage, a lipid-rich necrotic core, a ruptured fibrous cap, and plaque ulceration. CONCLUSIONS: MRA with VWI is a useful tool in the evaluation of carotid artery plaques. This imaging technique allows clinicians to identify plaques at risk of causing a neurovascular event. The presence of intraplaque hemorrhage, plaque ulceration, a ruptured fibrous cap, and a lipid-rich necrotic core are associated with neurovascular symptoms. The timely identification of these features could have a positive impact on neurovascular event prevention.

No Sex Differences in the Prevalence of Intracranial Aneurysms in Patients with Ascending Thoracic Aortic Aneurysms: A Multi-Center Experience.

BACKGROUND: Previous studies suggest a coprevalence of intracranial aneurysms (IA) in patients with infrarenal abdominal aortic aneurysms (AAA). We reviewed our multicenter experience in the detection/treatment of IAs in patients with ascending thoracic aortic aneurysms (ATAA) relative to patients without ATAA. METHODS: Surgical cases of ATAA repaired at 3 sites from January 1998 to December 2018 were retrospectively reviewed. Out of these patients, those with intracranial vascular imaging were selected for our study, and these individuals were concurrently randomly matched with a control group of patients who underwent intracranial vascular imaging without an ATAA in a 1:1 ratio by age, sex, smoking history, and year of intracranial vascular imaging. Conditional logistic regression was used to calculate odds ratios (OR). RESULTS: We reviewed 2176 ATAA repairs. 74% (n = 1,615) were men. Intracranial vascular imaging was available in 298 (13.7%) patients. Ninteen patients were found to have 22 IAs for a prevalence of 6.4%. Mean size of IA was 4.6 ± 3.3 mm; mean age at IA detection, 63.4 ± 12.1 years. IA was present on head imaging in 4.7% of male and 12.5% of female patients. Eleven (58%) patients were men. The OR of having IA in female versus male patients is 2.90, 95% confidence interval [CI] [1.08-7.50], P = 0.029. Time from IA diagnosis to ATAA repair was 1.7 ± 116.2 months. Two patients underwent treatment for IA, one ruptured and one unruptured. All were diagnosed before ATAA repair. Treatment included 1 clipping and 1 coiling with subsequent reintervention of the coiling using a flow diversion device. In the matched group of patients who had intracranial vascular imaging without ATAA, the rate of IA is 5.0%. IA was detected in 3.8% of males and 9.4% of female patients for an OR of 2.59, 95% CI [0.84-7.47], P = 0.083. Association within our study and matched groups, the OR of developing an IA with and without ATAA was not statistically significant 1.29, 95% CI [0.642.59], P = 0.48. There was also no evidence of sex differences in the association of ATAA with IA (interaction P = 0.88). The OR for the association of ATAA with IA was 1.33, 95% CI [0.46-3.84], P = 0.59 in females and 1.25, 95% CI [0.49-3.17], P = 0.64 in males. CONCLUSIONS: Our study found that IA was present in 6.4% of patients with ATAA who had intracranial vascular imaging available. The odds of IA were 1.29 times higher than a matched cohort of patients who had intracranial vascular imaging without ATAA but this failed to achieve statistical significance. We found that the odds of IA were more than 2 times higher in females than males for both those with ATAA (OR = 2.90) and those without ATAA (OR = 2.59); however, it only reached statistical significance in those with ATAA.

Newly Discovered Parotid Lesion: What Next?

When a parotid lesion is discovered incidentally, it can be challenging for the radiologist to provide specific recommendations for the next steps. This article describes how the radiologist can play an active role in managing incidentally discovered parotid lesions. First, we explore the significance of parotid lesions. Next, the pertinent anatomy of the parotid space is presented to develop an appropriate differential diagnosis. Lastly, we discuss critical clinical and imaging characteristics the radiologist can use to provide specific recommendations.

Iatrogenic left common carotid artery to right internal jugular vein arteriovenous fistula closure.

We report a minimally invasive approach to the repair of a 2.8-cm × 6.0-cm left proximal common carotid to right internal jugular vein arteriovenous fistula. A 47-year-old woman with coronavirus disease 2019 pneumonia had received extracorporeal membranous oxygenation and developed a rare, presumably cannulation-related, vascular injury. We used a plug designed and typically used for the endovascular management of a patent ductus arteriosus.

Imaging Characteristics and Reintervention in Patients after Radiation Induced Carotid Artery Stenting.

BACKGROUND: To evaluate and describe the radiographic imaging findings in a series of patients who underwent reintervention after radiation induced carotid artery stenting (RICAS). METHODS: A retrospective review of patients with prior RICAS and subsequent reintervention. RESULTS: We describe 10 patients including 8 male and 2 female patients with 12 reinterventions due to prior diagnosed radiation-induced carotid artery stenosis and subsequent stenting during the period 2000-2019. The rate of reintervention was found to be 10%. The pattern of stenosis is unique to this patient population including specifically long-segment stenosis, proximal and distal to the stent location, which tends not to occur in the atherosclerotic patient population. CONCLUSIONS: Careful surveillance after RICAS is necessary to assess for the risk and the unusual pattern of stenosis to offer reintervention in this high-risk patient population.

Focused versus conventional radiotherapy in spinal oncology: is there any difference in fusion rates and pseudoarthrosis?

INTRODUCTION: Radiotherapy is considered standard of care for adjuvant peri-operative treatment of many spinal tumors, including those with instrumented fusion. Unfortunately, radiation treatment has been linked to increased risk of pseudoarthrosis. Newer focused radiotherapy strategies with enhanced conformality could offer improved fusion rates for these patients, but this has not been confirmed. METHODS: We performed a retrospective analysis of patients at three tertiary care academic institutions with primary and secondary spinal malignancies that underwent resection, instrumented fusion, and peri-operative radiotherapy. Two board certified neuro-radiologists used the Lenke fusion score to grade fusion status at 6 and 12-months after surgery. Secondary outcomes included clinical pseudoarthrosis, wound complications, the effect of radiation timing and radiobiological dose delivered, the use of photons versus protons, tumor type, tumor location, and use of autograft on fusion outcomes. RESULTS: After review of 1252 spinal tumor patients, there were 60 patients with at least 6 months follow-up that were included in our analyses. Twenty-five of these patients received focused radiotherapy, 20 patients received conventional radiotherapy, and 15 patients were treated with protons. There was no significant difference between the groups for covariates such as smoking status, obesity, diabetes, intraoperative use of autograft, and use of peri-operative chemotherapy. There was a significantly higher rate of fusion for patients treated with focused radiotherapy compared to those treated with conventional radiotherapy at 6-months (64.0% versus 30.0%, Odds ratio: 4.15, p = 0.036) and 12-months (80.0% versus 42.1%, OR: 5.50, p = 0.022). There was a significantly higher rate of clinical pseudoarthrosis in the conventional radiotherapy cohort compared to patients in the focused radiotherapy cohort (19.1% versus 0%, p = 0.037). There was no difference in fusion outcomes for any of the secondary outcomes except for use of autograft. The use of intra-operative autograft was associated with an improved fusion at 12-months (66.7% versus 37.5%, OR: 3.33, p = 0.043). CONCLUSION: Focused radiotherapy may be associated with an improved rate of fusion and clinical pseudoarthrosis when compared to conventional radiation delivery strategies in patients with spinal tumors. Use of autograft at the time of surgery may be associated with improved 12-month fusion rates. Further large-scale prospective and randomized controlled studies are needed to better stratify the effects of radiation delivery modality in these patients.

Nutcracker phenomenon with a daily persistent headache as the primary symptom: Case series and a proposed pathogenesis model based on a novel MRI technique to evaluate for spinal epidural venous congestion.

OBJECTIVE: To determine if a specific population of patients with a daily persistent headache from onset have underlying nutcracker physiology and to propose a pathogenesis model for their headaches utilizing a novel MRI protocol. BACKGROUND: A single case report of a daily persistent headache associated with nutcracker syndrome was recently published. As the left renal vein has a connection to the spinal lumbar veins and secondarily to the spinal epidural venous plexus, one could hypothesize that renal vein compression could lead to persistent headache by altering spinal and cerebral venous pressure with secondary alterations in CSF pressure. The authors have published on a series of patients with a unique subtype of daily persistent headache from onset that appears to be caused by an abnormal reset of CSF pressure to an elevated state. The goal of the present study was to look for the presence of nutcracker physiology in this unique patient subgroup and to propose a pathogenesis model utilizing a novel MRI protocol to evaluate for retrograde lumbar vein flow and regional spinal epidural venous plexus congestion. MATERIALS AND METHODS: Case series of patients with a daily persistent headache from onset, head pressure, and whose headaches worsened in the Trendelenburg position. Patients were imaged with a 3 T MRI in the supine position from the lower diaphragm to the top of the pelvis with a dynamic angiogram centered over the left L2 lumbar vein. RESULTS: 12 patients were studied of which 8 were positive for left renal vein compression, lumbar vein dilation and early spinal epidural venous plexus enhancement. All were women. Mean age of headache onset was 39 years. Six of the 8 patients had a lumbar puncture, and all had a normal opening pressure. All improved with CSF volume removal although pain resolution lasted from hours to 6 months. The patient's headaches were marked by holocranial pressure and the majority displayed migrainous associated symptoms although none had a prior headache history. They did not complain of typical symptoms or signs of nutcracker syndrome. CONCLUSION: We suggest that patients with a daily persistent headache from onset who worsen in the Trendelenburg position may have underlying nutcracker physiology. From our imaging findings, it can be hypothesized that left renal vein compression leads to retrograde flow through the valveless lumbar vein which then leads to spinal epidural venous congestion and subsequently causes congestion of the cerebral venous system leading to an elevation of CSF pressure and to a daily headache. What appears to be unique about these patients is that a daily headache is their only manifestation of nutcracker physiology.

Scout it out! Wake-Up Stroke Protocol to Expedite MRI in Stroke Patients.

In wake-up stroke patients, magnetic resonance imaging (MRI) is useful to identify patients that would benefit from thrombolytic therapy. Our multidisciplinary stroke team developed and implemented a workflow to rapidly identify patients that are able to safely undergo an MRI exam, thus decreasing time to treatment. We employ a full-body CT scout image in our CT head protocol for acute stroke in order to identify implantable devices and foreign bodies. This protocol highlights the importance of radiology playing an active role on the multidisciplinary stroke team in order to effectively and promptly treat patients.

Arachnoid Web Fenestration: Diagnostic and Surgical Nuances.

Arachnoid web (AW) is a rare phenomenon that has only been described in small case reports and case series,1 most commonly presenting with upper motor neuron signs and subtle radiographic findings, such as the classically described "scalpel sign."2 In this report, we demonstrate the use of imaging and operative techniques that have not been previously shown in the literature as a video for AW. These include high-definition magnetic resonance imaging (MRI) sequences for preoperative diagnosis, use of intraoperative ultrasonography for identification of adhesions, and operative technique for AW fenestration (Video 1). The patient consented to this manuscript. A 64-year-old female patient developed progressive difficulty with balance and ambulation that particularly worsened over the last 4 months associated with tingling and numbness in the bilateral lower extremities. Physical examination revealed spastic gait and upper motor neuron signs in the lower extremities along with left foot drop. MRI revealed a chronic noncontrast-enhancing intramedullary lesion, along with a spinal cord indentation at the level T6 with an associated fiber between the cord and the posterior dura. Surgical intervention was performed with the use of intraoperative fluoroscopy and ultrasound for real-time identification of the surgical site and the AW. Under the microscope, the dura was incised while preserving the arachnoid. The AW was carefully dissected, leaving the portions that were tethered onto the cord. Two weeks postoperatively, the patient's gait was markedly improved, with resolved neurologic function in the lower extremities. Follow-up MRI at 3 months demonstrated resolved medullary syrinx and normalization of the spinal cord contour.

Higher Risk for Reintervention in Patients after Stenting for Radiation-Induced Internal Carotid Artery Stenosis: A Single-Center Analysis and Systematic Review.

BACKGROUND: This study aimed to review short- and long-term outcomes of all carotid artery stenting (CAS) in patients with radiation-induced (RI) internal carotid artery (ICA) stenosis compared with patients with atherosclerotic stenosis (AS). METHODS: We performed a single-center, multisite case-control study of transfemoral carotid artery intervention in patients stented for RI or AS. Cases of stented RI carotid arteries were identified using a CAS database covering January 2000 to December 2019. These patients were randomly matched 2:1 with stented patients because of AS by age, sex, and year of CAS. A conditional logistic regression model was performed to estimate the odds of reintervention in the RI group. Finally, a systematic review was performed to assess the outcomes of RI stenosis treated with CAS. RESULTS: There were 120 CAS in 113 patients because of RI ICA stenosis. Eighty-nine patients (78.8%) were male, and 68 patients (60.2%) were symptomatic. The reasons for radiation included most commonly treatment for diverse malignancies of the head and neck in 109 patients (96.5%). The mean radiation dose was 58.9 ± 15.6 Gy, and the time from radiation to CAS was 175.3 ± 140.4 months. Symptoms included 31 transient ischemic attacks (TIAs), 21 strokes (7 acute and 14 subacute), and 17 amaurosis fugax. The mean National Institutes of Health Stroke Scale in acute strokes was 8.7 ± 11.2. In asymptomatic patients, the indication for CAS was high-grade stenosis determined by duplex ultrasound. All CAS were successfully completed. Reinterventions were more frequent in the RI ICA stenosis cohort compared with the AS cohort (10.1% vs. 1.4%). Reinterventions occurred in 14 vessels, and causes for reintervention were restenosis in 12 followed by TIA/stroke in two vessels. On conditional regression modeling, patients with RI ICA stenosis were at a higher risk for reintervention (odds ratio = 7.1, 95% confidence interval = 2.1-32.8; P = 0.004). The mean follow-up was 33.7 ± 36.9 months, and the mortality across groups was no different (P = 0.12). CONCLUSIONS: In our single-center, multisite cohort study, patients who underwent CAS for RI ICA stenosis experienced a higher rate of restenosis and a higher number of reinterventions compared with CAS for AS. Although CAS is safe and effective for this RI ICA stenosis cohort, further data are needed to reduce the risk of restenosis, and close patient surveillance is warranted. In our systematic review, CAS was considered an excellent alternative option for the treatment of patients with RI ICA stenosis. However, careful patient selection is warranted because of the increased risk of restenosis on long-term follow-up.

Pneumatized middle ear ossicle - A normal variant.

It is important to be familiar with normal anatomic variants in order to not to mistake them for pathology. It is well known that the middle ear ossicles have varying normal morphology on gross anatomy, but can also be malformed in certain congenital syndromes or eroded in the setting of chronic ear infection or cholesteatoma. This case series describes the pneumatized ossicle on imaging, a rare normal anatomic variant.