Mucor Thrombus.

BACKGROUND: To describe a rare presentation of ischemic stroke secondary to angioinvasive mucormycosis and endovascular retrieval of mycotic thrombus with stenting of the compressed vessel. SUMMARY OF CASE: We report a case of angioinvasive mucormycosis that externally compressed and invaded the internal carotid artery causing ischemic cerebral infarction. A sample of the thrombus was obtained using a stent retriever. Subsequent pathological analysis was shown to be consistent with the diagnosis of angioinvasive mucormycosis. The thrombosed and compressed segment was recanalized with the deployment of a stent. CONCLUSIONS: The endovascular placement of an expandable stent in the setting of angioinvasive mucormycosis restored good cerebral blood flow in a proximal internal carotid artery occlusion. The patient's aphasia resolved following this intervention. Artifacts of CT angiography may result in the overestimation of acute arterial occlusions. Endovascular carotid stenting may be a palliative measure in the setting of angioinvasive rhino-cerebro-orbital mucormycosis.

Mortality in cerebral venous thrombosis: results from the national inpatient sample database.

BACKGROUND: Outcomes of cerebral venous thrombosis (CVT) vary from full recovery to death. Few studies have been performed examining epidemiologic and medical risk factors associated with high mortality in CVT. In this study, we examined the National Inpatient Sample (NIS) to determine the epidemiologic and medical risk factors associated with increased mortality from CVT. MATERIALS AND METHODS: Using the NIS from 2001 to 2008, patients who suffered from CVT were identified using the ICD-9 codes 437.6 (nonpyogenic thrombosis of intracranial venous sinus), 325 (phlebitis and thrombophlebitis of intracranial venous sinuses) and 671.5 (peripartum phlebitis and thrombosis, cerebral venous thrombosis, thrombosis of intracranial venous sinus). We analyzed the associations of demographic factors, risk factors, comorbidities, complications of CVT, and therapeutic interventions with in-hospital mortality. We performed a multivariate logistic regression analysis to determine which variables were independently associated with in-hospital mortality. RESULTS: 11,400 patients were hospitalized with CVT between 2001 and 2008. Two-hundred and thirty-two (2.0%) suffered in-hospital mortality. Patients 15-49 years old had the lowest mortality rate (1.5%) compared with 2.8% for patients aged 50-64 (p < 0.001) and 6.1% for patients ≥65 years old (p < 0.001). The most common condition associated with CVT was pregnancy/puerperium (24.6%), and these women had a low mortality rate (0.4%). On multivariate analysis, the comorbidity most strongly associated with increased risk of mortality was sepsis (mortality rate 15.6%, OR = 7.5, 95% CI = 4.79-11.53, p < 0.001). Malignancy, underlying autoimmune disease and substance abuse were also independently associated with mortality, but with lower mortality rates (<5%). Complications associated with increased risk of mortality included paralysis (8.0%, OR = 3.4, 95% CI = 3.17-6.96, p < 0.001), intracranial hemorrhage (8.7%, OR = 5.4, 95% CI = 4.38-7.96, p < 0.001), and hydrocephalus (15.0%, OR = 3.2, 95% CI = 5.54-15.11, p = 0.004). Demographic variables associated with decreased mortality on multivariate analysis were male gender (2.1%, OR = 0.62, 95% CI = 0.43-0.87, p = 0.006) and Asian/Pacific Islander race (OR = 0.00, 95% CI = 0-0.27, p < 001). CONCLUSIONS: CVT is associated with a low in-hospital mortality rate. Amongst patients suffering CVT, male gender and Asian/Pacific Islander race were independently associated with lower odds of in-hospital mortality when compared to their female and white counterparts, respectively. Septic patients with CVT have the greatest risk of in-hospital mortality. Hydrocephalus, intracranial hemorrhage, and motor deficits are also associated with higher risk of death. Our results build on previous evidence that serves to define a group of patients with CVT at high risk of early death.

Postprocedural Thrombosis following Endovascular Treatment of Intracranial Aneurysm with Flow Diverters or Coiling: A Histologic Study.

Endovascular treatment of aneurysms with flow diverters or coiling is sometimes complicated by intraprocedural or postprocedural thrombosis along or within the devices. Thrombus composition and structure associated with such complications may provide insights into mechanisms of thrombus formation and clinical strategies to remove the thrombus. We present a retrospective histopathologic study of 4 patients who underwent mechanical thrombectomy due to acute occlusion of either implanted flow diverter devices or along coils during the treatment of intracranial aneurysm.

Anatomy of Spinal Venous Drainage for the Neurointerventionalist: From Puncture Site to Intervertebral Foramen.

CSF-venous fistula is a relatively novel entity that is increasingly being recognized as a cause for spontaneous intracranial hypotension. Recently, our group published the first series of transvenous embolization of CSF-venous fistulas in this journal. Having now performed the procedure in 60 patients, we have garnered increasing familiarity with the anatomy and how to navigate our way through the venous system to any intervertebral foramen in the cervical, thoracic, and lumbar spine. The first part of this review summarizes the organization of spinal venous drainage as described in classic anatomy and interventional radiology texts, the same works that we studied when attempting our first cases. In the second part, we draw mostly on our own experience to provide a practical roadmap from the puncture site to the foramen. On the basis of these 2 parts, we hope this article will serve to collate the relevant anatomic knowledge and give confidence to colleagues who wish to embark on transvenous spinal procedures.

Disparities in the Use of Mechanical Thrombectomy Alone Compared with Adjunctive Intravenous Thrombolysis in Acute Ischemic Stroke in the United States.

BACKGROUND AND PURPOSE: For patients with large-vessel occlusion, mechanical thrombectomy (MT) without IV-tPA is a proved strategy. The relative benefit of direct MT versus MT+IV-tPA for patients with indications for IV-tPA is being actively investigated. We used a national inpatient database to assess trends in use and patient profiles after MT+IV-tPA versus mechanical thrombectomy alone. MATERIALS AND METHODS: The National Inpatient Sample was queried between 2013 and 2018 for patients undergoing mechanical thrombectomy for acute ischemic stroke. Patients who received mechanical thrombectomy alone were compared with those who underwent MT+IV-tPA. The Cochran-Armitage test was conducted to assess the linear trend of use of mechanical thrombectomy alone among the entire cohort and between admissions involving non-White and White patients. All estimates were nationalized using discharge weights. RESULTS: A total of 89,645 weighted admissions were identified pertaining to mechanical thrombectomy for acute ischemic stroke from 2013 to 2018. Of these, 59,935 (66.9%) admissions involved mechanical thrombectomy alone. There was an increase in the trend toward the use of mechanical thrombectomy alone (trend: 3.26%; P < .001) per year. Multivariable regression analysis regarding patient profiles indicated that patients who identified as Black (OR = 0.83, P = .001) or Hispanic (OR = 0.79; P < .001) were more likely to undergo mechanical thrombectomy alone compared with those who identified as White. There was no statistically significant difference in the slope between non-White and White populations receiving mechanical thrombectomy alone (trend: +0.93% in favor of non-White; P = .096). CONCLUSIONS: Our results indicated that mechanical thrombectomy alone was used more frequently than MT+IV-tPA among patients with acute ischemic stroke. The disparity between those who identify as White and non-White persisted across the years, though it is closing.

Iatrogenic Foreign Materials Associated with Retrieved Clot Tissue via Mechanical Thrombectomy.

BACKGROUND AND PURPOSE: Hydrophilic polymers and polytetrafluoroethylene liners, commonly used in the construction of endovascular devices, occasionally separate from devices with subsequent embolization. We determined the frequency of such materials in thrombus specimens retrieved by mechanical thrombectomy in patients with stroke. MATERIALS AND METHODS: We retrospectively reviewed H&E-stained thrombus sections for presence and types of foreign materials. We identified 4 types of foreign materials-Type I: material was light green with refraction and had a homogeneous texture; type II: material was light gray and/or dark gray, thin, and loose or attenuated in texture; type III: material was light green with refraction, solitary in texture, irregular in shape, and was often associated with round or oval bubblelike particles and/or diffuse black particles; and type IV: material had homogeneous texture and was light pink or red. In addition, polymer materials from different layers of used mechanical thrombectomy catheters were compared with the foreign materials found in thrombus specimens. RESULTS: A total of 101 thrombi were evaluated. Foreign materials were found in 53 (52.5%) thrombus samples. The most common type was type I (92%), followed by type II (30%). The histopathologic features of the polymer materials from mechanical thrombectomy catheters were similar to the foreign materials found in thrombus specimens. The inner polytetrafluoroethylene liner and coating layer of catheters resembled type I and type II of the foreign materials, respectively. CONCLUSIONS: Foreign polymer materials are present in approximately half of retrieved thrombi, most commonly polytetrafluoroethylene from catheter liners and less from hydrophilic coatings.

Efficacy of Asahi Fubuki as a Guiding Catheter for Mechanical Thrombectomy: An Institutional Case Series.

Treatment outcomes of mechanical thrombectomy for acute stroke secondary to large-vessel occlusion in which the Asahi Fubuki was used as a guide catheter were reviewed. Among 154 patients treated with mechanical thrombectomy, the Fubuki was successfully delivered to the cervical ICA in 151 cases (98.1%) and the lesion was successfully crossed in 150 cases (97.4%). Median times to lesion crossing and revascularization were 9 and 19 minutes, respectively.

Clinical Presentation and Imaging Findings of Patients with Dural Arteriovenous Fistulas with an Angiographic Pseudophlebitic Pattern.

BACKGROUND AND PURPOSE: The pseudophlebitic pattern is an increasingly recognized angiographic manifestation of chronic venous congestion in the setting of a cranial dural arteriovenous fistula. We sought to study the clinical and radiologic manifestations of patients with the pseudophlebitic pattern. MATERIALS AND METHODS: We retrospectively reviewed a cohort of patients with dural arteriovenous fistulas evaluated at our institution from 2008 to 2020. Angiograms were reviewed to classify dural arteriovenous fistulas and document the presence or absence of a pseudophlebitic pattern, defined as the presence of serpiginous and tortuous collateral, bridging, and cortical veins with an associated delay in circulation time of the normal brain. We then studied the association between the pseudophlebitic pattern and clinical presentation and MR imaging findings. RESULTS: Two hundred one patients were included. Patients with a pseudophlebitic pattern had more hemorrhage (22.8% versus 8.4%, P = .005), gait changes and ataxia (6.0% versus 0.0%, P = 0.002), cognitive changes (6.9% versus 1.4%, P = .04), and seizures (8.6% versus 2.1%, P = .03). On MR imaging, the pseudophlebitic pattern was associated with higher rates of cerebral edema (70.9% versus 2.9%, P < .0001), chronic hemosiderin deposition and microhemorrhage (17.3% versus 2.2%, P = .0002), and dilated transmedullary veins (47.1% versus 0.0%, P < .0001). When we considered only patients with malignant fistulas, there was no difference in hemorrhage at presentation between the 2 groups (22.6% versus 22.8%, P = .99). Patients with a pseudophlebitic pattern did have higher rates of nonhemorrhagic neurologic deficits (24.1% versus 9.4%, P = .03). CONCLUSIONS: The pseudophlebitic pattern was associated with high rates of brain parenchymal changes and neurologic symptoms in this cohort of patients with dural arteriovenous fistulas.

A Multicenter Pilot Study on the Clinical Utility of Computational Modeling for Flow-Diverter Treatment Planning.

BACKGROUND AND PURPOSE: Selection of the correct flow-diverter size is critical for cerebral aneurysm treatment success, but it remains challenging due to the interplay of device size, anatomy, and deployment. Current convention does not address these challenges well. The goals of this pilot study were to determine whether computational modeling improves flow-diverter sizing over current convention and to validate simulated deployments. MATERIALS AND METHODS: Seven experienced neurosurgeons and interventional neuroradiologists used computational modeling to prospectively plan 19 clinical interventions. In each patient case, physicians simulated 2-4 flow-diverter sizes that were under consideration based on preprocedural imaging. In addition, physicians identified a preferred device size using the current convention. A questionnaire on the impact of computational modeling on the procedure was completed immediately after treatment. Rotational angiography image data were acquired after treatment and compared with flow-diverter simulations to validate the output of the software platform. RESULTS: According to questionnaire responses, physicians found the simulations useful for treatment planning, and they increased their confidence in device selection in 94.7% of cases. After viewing the simulations results, physicians selected a device size that was different from the original conventionally planned device size in 63.2% of cases. The average absolute difference between clinical and simulated flow-diverter lengths was 2.1 mm. In 57% of cases, average simulated flow-diverter diameters were within the measurement uncertainty of clinical flow-diverter diameters. CONCLUSIONS: Physicians found computational modeling to be an impactful and useful tool for flow-diverter treatment planning. Validation results showed good agreement between simulated and clinical flow-diverter diameters and lengths.

Vascular compression as a potential cause of occipital neuralgia: a case report.

Vascular compression is a well-established cause of cranial nerve neuralgic syndromes. A unique case is presented that demonstrates that vascular compression may be a possible cause of occipital neuralgia. A 48-year-old woman with refractory left occipital neuralgia revealed on magnetic resonance imaging and computed tomographic imaging of the upper cervical spine an atypically low loop of the left posterior inferior cerebellar artery (PICA), clearly indenting the dorsal upper cervical roots. During surgery, the PICA loop was interdigitated with the C1 and C2 dorsal roots. Microvascular decompression alone has never been described for occipital neuralgia, despite the strong clinical correlation in this case. Therefore, both sectioning the dorsal roots of C2 and microvascular decompression of the PICA loop were performed. Postoperatively, the patient experienced complete cure of her neuralgia. Vascular compression as a cause of refractory occipital neuralgia should be considered when assessing surgical options.

Review of the Imaging Features of Benign Osteoporotic and Malignant Vertebral Compression Fractures.

Vertebral compression fractures are very common, especially in the elderly. Benign osteoporotic and malignant vertebral compression fractures have extremely different management and prognostic implications. Although there is an overlap in appearances, characteristic imaging features can aid in the distinction between these 2 types of compression fractures. The aim of this review is to characterize the imaging features of benign and malignant vertebral compression fractures seen with CT, PET, SPECT, and MR imaging.

Dilated Vein of the Filum Terminale on MRI: A Marker for Deep Lumbar and Sacral Dural and Epidural Arteriovenous Fistulas.

BACKGROUND AND PURPOSE: Conventional MR imaging can provide important clues regarding the location of a spinal vascular malformation. We hypothesized that a dilated vein of the filum terminale, identified as a curvilinear flow void on T2WI, could be an imaging marker for a lower lumbar (L3-L5) or sacral fistula. MATERIALS AND METHODS: We retrospectively identified all spinal dural and spinal epidural arteriovenous fistulas from 2 large tertiary referral centers from 2005 to 2018. All patients had a lumbar spinal MR imaging and a conventional spinal angiography. Images were reviewed by 2 neuroradiologists who categorized the level of the arterial feeder to the fistula and the presence or absence of a dilated vein of the filum terminale on T2WI and T1 postcontrast images. We calculated the sensitivity, specificity, positive predictive value, and negative predictive value of the presence of a dilated filum terminale vein for a deep lumbar or sacral fistula. RESULTS: One hundred sixty-two patients were included. An enlarged filum terminale vein was identified in 39 patients. Sensitivity, specificity, positive predictive value, and negative predictive value of the presence of a dilated filum terminale vein for a deep lumbar or sacral fistula were 86%, 98.3%, 94.9%, and 95.1%, respectively. CONCLUSIONS: The presence of a dilated vein of the filum terminale can accurately localize a spinal dural arteriovenous fistula/spinal epidural arteriovenous fistula to the lower lumbar or sacral spine in patients being evaluated for such lesions. This finding can be used to facilitate both noninvasive and conventional spinal angiography.

Elevated adenosine deaminase activity and hereditary hemolytic anemia. Evidence for abnormal translational control of protein synthesis.

We have investigated the molecular basis of the marked elevation in erythrocyte adenosine deaminase (ADA) activity in a kindred with hereditary hemolytic anemia. Red cell ADA-specific activity was verified to be 70- to 100-fold normal levels. Western blots demonstrated a corresponding increase in erythrocyte ADA-specific immunoreactive protein. Analysis of genomic DNA revealed no evidence for amplification or major structural changes in the ADA gene. ADA-specific messenger RNA (mRNA) from proband reticulocytes was comparable in size and amount to mRNA from control reticulocytes. Translation of proband poly A+ reticulocyte mRNA in a rabbit reticulocyte lysate system and immunoprecipitation of 35S-labeled protein products with anti-ADA antibody yielded a band of approximately 42,000 apparent mol wt that was absent in translation products from control reticulocyte mRNAs. These data suggest that the increased ADA activity in red cells in this disorder results from the increased translation of an aberrant ADA mRNA.

HydroCoil for Endovascular Aneurysm Occlusion (HEAL) study: 3-6 month angiographic follow-up results.

BACKGROUND AND PURPOSE: The HydroCoil Embolic System (HES) was developed reduce recurrences of aneurysms relative to platinum coils. This study was conducted to evaluate the recurrence rate of cerebral aneurysms 3-6 months after treatment with HES. METHODS: We report the results in 135 cerebral aneurysms treated with HES in a prospective multicenter registry. Angiographic results 3-6 months after treatment were evaluated at a core laboratory. Wide variation in HES utilization within the HydroCoil for Endovascular Aneurysm Occlusion (HEAL) registry (HES representing 5% to 100% of the coil length used) allowed for subgroup analysis with regard to percentage length, last coil used, and packing attenuation in small (<10 mm) aneurysms. RESULTS: The overall recurrence rate was 38 (28.1%) of 135, which included a number of large, giant, and previously recurrent aneurysms. When HES represented > or = 75% of coil length, the recurrence rate was 0 (0%) of 18, whereas with <75% length of HES, the recurrence rate was 16 (23%) of 71 (P = .035). When the final coil deposited was a HES coil, the recurrence rate was 6 (11%) of 53, whereas when the final coil was platinum, the recurrence rate was 10 (29%) of 34 (P = .047). When the packing attenuation was > or = 50%, the recurrence rate was 11 (19%) of 59, whereas for packing attenuation <50%, the recurrence rate was 5 (18%) of 28. The packing attenuation calculations were very error-prone. CONCLUSION: Although the overall recurrence rates for small and large aneurysms in HEAL were no lower than published rates for aneurysms treated with platinum coils, patients treated in HEAL had a reduced recurrence rate when greater than 75% of the coil length used to treat an aneurysm was HES and when the final coil was HES.

Kyphoplasty: an assessment of a new technology.

Kyphoplasty is a new procedure for the treatment of vertebral compression fractures that is being performed with increasing frequency. Representing the Technology Assessment Committee of the American Society of Interventional and Therapeutic Neuroradiology, we present a review of the available information regarding this new technology.

Ready or not, here they come: randomized trials evaluating new endovascular aneurysm therapies.

Randomized trials evaluating endovascular therapy are currently underway. The results of these trials will present us with both new answers and new questions.

Observer agreement in the assessment of endovascular aneurysm therapy and aneurysm recurrence.

BACKGROUND AND PURPOSE: Assessments of completeness of endovascular cerebral aneurysm therapy are commonly reported in the literature. We studied several aneurysm assessment scales with regard to observer variability, which directly affects validity of these scales. MATERIALS AND METHODS: Initial aneurysm occlusion and occlusion at a follow-up angiogram at 3-6 months were assessed independently by 2 experienced observers. Assessments of each aneurysm were made using 3 different scales: 4-response (complete, dog ear, neck remnant, incomplete), 3-response (complete, near-complete, incomplete), and 2-response (complete or near-complete, incomplete). Assessments were also made of comparisons of initial treatment angiogram with follow-up angiogram using 2 different scales: 3-response (better, same, worse) and 2-point response (not worse, worse). RESULTS: With assessments of both initial and follow-up angiograms, interobserver and intraobserver agreement was progressively worse with increasing response choices in the scales. Observer agreement on assessments of initial angiograms (kappa values 0.48-0.67) was worse than that for follow-up angiograms (kappa values 0.66-0.97). For the comparisons of the initial angiogram with the follow-up angiogram, there was worse observer agreement with the 3-response scale (kappa values 0.64-0.71) than with the 2-response scale (kappa values 0.78-0.89). CONCLUSION: Interobserver and intraobserver variability are inherent to assessment scales of completeness of cerebral aneurysm therapy. Observer variability is substantially better in scales that offer fewer observer responses. However, scales with fewer observer responses may not identify aneurysm subgroups that have differing risks of recurrence and/or rehemorrhage.

Fate of submitted manuscripts rejected from the American Journal of Neuroradiology: outcomes and commentary.

BACKGROUND AND PURPOSE: The purpose of this study was to determine the publication fate of submissions previously rejected from the American Journal of Neuroradiology (AJNR) to provide guidance to authors who receive rejection notices. MATERIALS AND METHODS: A retrospective search by using MEDLINE of all submissions rejected from AJNR in 2004 was performed to identify subsequently published manuscripts. The fate of subsequently published manuscripts was analyzed as a function of submission type (major study, technical note, or case report), publication delay, publishing journal type (neuroradiology, general radiology, or clinical neuroscience journal), impact factor, publication volume, and circulation volume. RESULTS: Of the 554 rejected submissions to AJNR, 315 (56%) were subsequently published in 115 different journals, with the journal Neuroradiology publishing the greatest number of articles (37 [12%] of 315). The mean publication delay was 15.8 +/- 7.5 months. Major studies were more likely than case reports to be subsequently published (P = .034), but all 3 subtypes were published at rates greater than 50%. Radiologic journals collectively published approximately 60% of subsequent publications, whereas neurosurgery and neurology journals published 27% of rejected manuscripts. The mean impact factor of journals subsequently publishing rejected manuscripts was 1.8 +/- 1.3 (AJNR = 2.5), and 24 (7.5%) manuscripts were subsequently published in journals with higher impact factors than AJNR. CONCLUSIONS: These findings should give hope to authors receiving a rejection from AJNR, because greater than 50% of articles rejected from AJNR are subsequently published within 2-3 years, irrespective of publication type, into high-quality journals.

Endovascular treatment of epistaxis in patients with hereditary hemorrhagic telangiectasia.

BACKGROUND AND PURPOSE: The treatment of epistaxis in patients with hereditary hemorrhagic telangiectasia can be very challenging. The purpose of our study was to evaluate our experience with endovascular epistaxis embolization in patients with hemorrhagic hereditary telangiectasia and to compare this with our experience in patients treated for idiopathic epistaxis. MATERIALS AND METHODS: Over a 6-year period, we treated 22 patients with epistaxis by using endovascular embolization. Twelve of 22 patients had hereditary hemorrhagic telangiectasia; 10 patients had idiopathic epistaxis. The angiographic findings, efficacy of treatment, and complications for both groups were compared. RESULTS: Patients with hereditary hemorrhagic telangiectasia had angiographic abnormalities in 92% of cases compared with only 30% in the idiopathic epistaxis group. Compared with a group of 10 patients treated for other causes of epistaxis, those with hereditary hemorrhagic telangiectasia required significantly more re-embolization treatments or additional surgical procedures because of continued or recurrent bleeding episodes after embolization (P=.03). Complications were rare; a single patient in the idiopathic epistaxis group had a self-limited groin hematoma and postembolization facial pain. CONCLUSION: Endovascular embolization of epistaxis is a safe procedure that can be useful for patients with severe acute epistaxis or chronic persistent bleeding. Patients who undergo endovascular embolization for epistaxis related to hereditary hemorrhagic telangiectasia require repeat embolization and subsequent surgical procedures more often than those with idiopathic epistaxis.

Bone formation in elastase-induced rabbit aneurysms embolized with platinum coils: report of 2 cases.

Histologic findings in 71 elastase-induced rabbit aneurysms embolized with platinum coils were retrospectively reviewed. Mature bone formation was found in 2 aneurysms, one with coils implanted for 3 months and the other with coils implanted for 1 year. We present the histologic findings and offer potential explanations for these observations. These findings may be relevant in understanding mechanisms of aneurysm healing after coil embolization.