Reducing frame rate and pulse rate for routine diagnostic cerebral angiography: ALARA principles in practice.

OBJECTIVE: Diagnostic cerebral angiograms (DCAs) are widely used in neurosurgery due to their high sensitivity and specificity to diagnose and characterize pathology using ionizing radiation. Eliminating unnecessary radiation is critical to reduce risk to patients, providers, and health care staff. We investigated if reducing pulse and frame rates during routine DCAs would decrease radiation burden without compromising image quality. METHODS: We performed a retrospective review of prospectively acquired data after implementing a quality improvement protocol in which pulse rate and frame rate were reduced from 15 p/s to 7.5 p/s and 7.5 f/s to 4.0 f/s respectively. Radiation doses and exposures were calculated. Two endovascular neurosurgeons reviewed randomly selected angiograms of both doses and blindly assessed their quality. RESULTS: A total of 40 consecutive angiograms were retrospectively analyzed, 20 prior to the protocol change and 20 after. After the intervention, radiation dose, radiation per run, total exposure, and exposure per run were all significantly decreased even after adjustment for BMI (all p<0.05). On multivariable analysis, we identified a 46% decrease in total radiation dose and 39% decrease in exposure without compromising image quality or procedure time. CONCLUSIONS: We demonstrated that for routine DCAs, pulse rate of 7.5 with a frame rate of 4.0 is sufficient to obtain diagnostic information without compromising image quality or elongating procedure time. In the interest of patient, provider, and health care staff safety, we strongly encourage all interventionalists to be cognizant of radiation usage to avoid unnecessary radiation exposure and consequential health risks.

Direct Transorbital Approach for Treatment of Carotid Cavernous Fistula: An Illustrative Case Series.

BACKGROUND AND OBJECTIVES: Endovascular techniques have become the first-line treatment for carotid-cavernous fistulas (CCFs). Direct transorbital venous access may be used if anatomic constraints limit standard transarterial or transvenous access. We describe our institutional experience with the transorbital approach for Barrow Type A-D CCFs. METHODS: Patients with CCFs undergoing transorbital endovascular treatment at our institution between 2017 and 2019 were retrospectively reviewed. Demographic, treatment, and outcome data were collected. RESULTS: Eight patients met inclusion criteria, 4 female and 4 male patients. The mean age was 43 years, with 6 right-sided CCF and 2 left-sided CCFs. Symptoms were present for an average of 1.5 months before treatment. All patients presented with eye pain and subjective visual changes. Seven (87.5%) patients presented with proptosis, 6 (75%) patients had elevated intraocular pressure (IOP), and 3 (37.5%) patients had ophthalmoplegia. Six CCFs (75%) were spontaneous, and 2 CCFs (25%) were traumatic. Barrow types were A (n = 1), B (n = 1), C (n = 1), and D (n = 5). All patients underwent direct percutaneous transorbital embolization with coils followed by Onyx. Three patients had undergone prior transarterial and/or transvenous treatment. A radiographic cure was obtained in all patients after direct transorbital embolization. After CCF cure, cranial nerve palsies resolved in 66.7% of patients, visual acuity in the affected eye was improved or stable in 75% of patients, and IOP had normalized in 85.7% of patients. Proptosis improved in all patients, with complete resolution in 75%. CONCLUSION: Direct transorbital embolization is a safe and potentially curative treatment for all 4 Barrow types of CCFs.

Microsurgical Resection of a Giant Posterior Fossa Aneurysmal Malformation in a 21-Month-Old.

Pediatric aneurysms commonly occur in the vertebrobasilar circulation with complex morphologies.1 "Aneurysmal malformations," or fistulous vessel dilations without a nidus, have also been described.2 Vessel friability and sensitivity to blood loss can complicate surgery. A 21-month-old male with motor and speech delay was found to have a giant posterior fossa aneurysmal malformation. He was lethargic, with minimal speech, and moved all extremities with mild hypotonia. Imaging demonstrated a 6.9 × 5.1 × 4.6 cm aneurysm arising from a fenestrated right V4 segment. This communicated via a single connection with the deep venous system, draining through the superior vermian cistern veins, posterior mesencephalic vein, basal vein of Galen, and inferior sagittal sinus, consistent with an arteriovenous fistula with secondary aneurysmal dilatation. Endovascular sacrifice was not feasible, in addition to concern for swelling after embolization. Three-dimensional modeling confirmed close proximity of the single inflow and outflow tracts. A suboccipital and left far lateral craniotomy for clip trapping and excision of the aneurysmal arteriovenous malformation was performed in a lateral position to completely decompress the brainstem (Video 1). Angiography before closure and postoperative vascular imaging demonstrated complete aneurysmal resection and fistula disconnection, with patency of normal vasculature. The postoperative course was notable for transient swallowing difficulties likely from lower cranial nerve irritation and refractory hydrocephalus requiring a shunt. The patient was meeting all developmental milestones at 2-year follow-up. This case highlights the complex vascular pathology often seen in pediatric patients, as well as the importance of presurgical planning and careful microsurgical technique in achieving a successful outcome.

Arteriovenous malformation surgery in children: the Rady Children's Hospital experience (2002-2019).

PURPOSE: Compared to adult AVMs, there is a paucity of data on the microsurgical treatment of pediatric AVMs. We report our institutional experience with pediatric AVMs treated by microsurgical resection with or without endovascular embolization and radiation therapy. METHODS: We retrospectively reviewed all patients ≤ 18 years of age with cerebral AVMs that underwent microsurgical resection at Rady Children's Hospital 2002-2019. RESULTS: Eighty-nine patients met inclusion criteria. The mean age was 10.3 ± 5.0 years, and 56% of patients were male. In total, 72 (81%) patients presented with rupture. Patients with unruptured AVMs presented with headache (n = 5, 29.4%), seizure (n = 9, 52.9%), or incidental finding (n = 3, 17.7%). The mean presenting mRS was 2.8 ± 1.8. AVM location was lobar in 78%, cerebellar/brainstem in 15%, and deep supratentorial in 8%. Spetzler-Martin grade was I in 28%, II in 45%, III in 20%, IV in 6%, and V in 1%. Preoperative embolization was utilized in 38% of patients and more frequently in unruptured than ruptured AVMs (62% vs. 32%, p = 0.022). Radiographic obliteration was achieved in 76/89 (85.4%) patients. Complications occurred in 7 (8%) patients. Annualized rates of delayed rebleeding and recurrence were 1.2% and 0.9%, respectively. The mean follow-up was 2.8 ± 3.1 years. A good neurological outcome (mRS score ≤ 2) was obtained in 80.9% of patients at last follow-up and was improved relative to presentation for 75% of patients. CONCLUSIONS: Our case series demonstrates high rates of radiographic obliteration and relatively low incidence of neurologic complications of treatment or AVM recurrence.

Site of Occlusion May Influence Decision to Perform Thrombectomy Under General Anesthesia or Conscious Sedation.

BACKGROUND: Although mechanical thrombectomy has become the standard of care for large-vessel occlusion, the role of conscious sedation versus general anesthesia (GA) with intubation during thrombectomy remains controversial. Aphasia may increase patient agitation or apparent uncooperativeness/confusion and thereby lead to higher use of GA. The purpose of this study was to identify risk factors for GA and determine if the side of vessel occlusion potentially impacts GA rates. MATERIALS AND METHODS: Patients who underwent mechanical thrombectomy of the middle cerebral artery (MCA) for acute ischemic stroke at our institution between April 2014 and July 2017 were retrospectively reviewed. Patient characteristics, procedural factors, and outcomes were assessed using multivariate regression analyses. Mediation analysis was utilized to investigate whether aphasia lies on the causal pathway between left-sided MCA stroke and GA. RESULTS: Overall, 112 patients were included: 62 with left-sided and 50 with right-sided MCA occlusion. Patients with left-sided MCA occlusion presented with aphasia significantly more often those with right-sided occlusion (90.3% vs. 32.0%; P<0.001). GA rates were significantly higher for patients with left-sided compared with right-sided MCA occlusion (45.2% vs. 20.0%; P=0.028). Aphasia mediated 91.3% of the effect of MCA stroke laterality on GA (P=0.02). GA was associated with increased door-to-groin-puncture time (106.4% increase; 95% confidence interval, 24.1%-243.4%; P=0.006) and adverse discharge outcome (odds ratio, 1.04; 95% confidence interval, 1.01-1.07; P=0.019). CONCLUSIONS: Patients who had a stroke with left-sided MCA occlusion are more likely to undergo GA for mechanical thrombectomy than those with right-sided MCA occlusion. Aphasia may mediate this effect and understanding this relationship may decrease GA rates through modification of management protocols, potentially leading to improved clinical outcomes. Our study suggests that GA should preferentially be considered for the subset of patients with acute ischemic stroke undergoing mechanical thrombectomy for left-sided MCA occlusion.

Antiplatelet therapy within 24 hours of tPA: lessons learned from patients requiring combined thrombectomy and stenting for acute ischemic stroke.

OBJECTIVE: Although stroke guidelines recommend antiplatelets be started 24 hours after tissue plasminogen activator (tPA), select mechanical thrombectomy (MT) patients with luminal irregularities or underlying intracranial atherosclerotic disease may benefit from earlier antiplatelet administration. METHODS: We explore the safety of early (<24 hours) post-tPA antiplatelet use by retrospectively reviewing patients who underwent MT and stent placement for acute ischemic stroke from June 2015 to April 2018 at our institution. RESULTS: Six patients met inclusion criteria. Median presenting and pre-operative National Institutes of Health Stroke Scale scores were 14 (Interquartile Range [IQR] 5.5-17.3) and 16 (IQR 13.7-18.7), respectively. Five patients received standard intravenous (IV) tPA and one patient received intra-arterial tPA. Median time from symptom onset to IV tPA was 120 min (IQR 78-204 min). Median time between tPA and antiplatelet administration was 4.9 hours (IQR 3.0-6.7 hours). Clots were successfully removed from the internal carotid artery (ICA) or middle cerebral artery (MCA) in 5 patients, the anterior cerebral artery (ACA) in one patient, and the vertebrobasilar junction in one patient. All patients underwent MT before stenting and achieved thrombolysis in cerebral infarction 2B recanalization. Stents were placed in the ICA (n=4), common carotid artery (n=1), and basilar artery (n=1). The median time from stroke onset to endovascular access was 185 min (IQR 136-417 min). No patients experienced symptomatic post-procedure intracranial hemorrhage (ICH). Median modified Rankin Scale score on discharge was 3.5. CONCLUSIONS: Antiplatelets within 24 hours of tPA did not result in symptomatic ICH in this series. The safety and efficacy of early antiplatelet administration after tPA in select patients following mechanical thrombectomy warrants further study.

Simulator Training for Endovascular Neurosurgery.

Simulation-based training has become common practice across medical specialties, especially for learning complex skills performed in high-risk environments. In the field of endovascular neurosurgery, the demand for consequence- and risk-free learning environments led to the development of simulation devices valuable for medical trainees. The goal of this protocol is to provide instructive guidelines for the use of an endovascular neurosurgery simulator in an academic setting. The simulator provides trainees with the opportunity to receive realistic feedback on their knowledge of anatomy, as well as haptic feedback indicative of their success in handling the catheter-based systems without negative consequences. The utility of this specific protocol in relation to other neuroendovascular training modalities is also discussed.

The Potential Impact of "Take the Volume Pledge" on Outcomes After Carotid Artery Stenting.

BACKGROUND: The "Volume Pledge" aims to centralize carotid artery stenting (CAS) to hospitals and surgeons performing ≥10 and ≥5 procedures annually, respectively. OBJECTIVE: To compare outcomes after CAS between hospitals and surgeons meeting or not meeting the Volume Pledge thresholds. METHODS: We queried the Nationwide Inpatient Sample for CAS admissions. Hospitals and surgeons were categorized as low volume and high volume (HV) based on the Volume Pledge. Multivariable hierarchical regression models were used to examine the impact of hospital volume (2005-2011) and surgeon volume (2005-2009) on perioperative outcomes. RESULTS: Between 2005 and 2011, 22 215 patients were identified. Most patients underwent CAS by HV hospitals (86.4%). No differences in poor outcome (composite endpoint of in-hospital mortality, postoperative neurological or cardiac complications) were observed by hospital volume but HV hospitals did decrease the likelihood of other complications, nonroutine discharge, and prolonged hospitalization. From 2005 to 2009, 9454 CAS admissions were associated with physician identifiers. Most patients received CAS by HV surgeons (79.2%). On multivariable analysis, hospital volume was not associated with improved outcomes but HV surgeons decreased odds of poor outcome (odds ratio [OR] 0.76, 95% confidence interval [CI] 0.59-0.97; P = .028), complications (OR 0.56, 95% CI 0.46-0.71, P < .001), nonroutine discharge (OR 0.70, 95% CI 0.57-0.87; P = .001), and prolonged hospitalization (OR 0.52, 95% 0.44-0.61, P < .001). CONCLUSION: Most patients receive CAS by hospitals and providers meeting the Volume Pledge threshold for CAS. Surgeons but not hospitals who met the policy's volume standards were associated with superior outcomes across all measured outcomes.

Epidemiology, Natural History, and Clinical Presentation of Large Vessel Ischemic Stroke.

Large vessel occlusions (LVOs), variably defined as blockages of the proximal intracranial anterior and posterior circulation, account for approximately 24% to 46% of acute ischemic strokes. Commonly refractory to intravenous tissue plasminogen activator (tPA), LVOs place large cerebral territories at ischemic risk and cause high rates of morbidity and mortality without further treatment. Over the past few years, an abundance of high-quality data has demonstrated the efficacy of endovascular thrombectomy for improving clinical outcomes in patients with LVOs, transforming the treatment algorithm for affected patients. In this review, we discuss the epidemiology, pathophysiology, natural history, and clinical presentation of LVOs as a framework for understanding the recent clinical strides of the endovascular era.

Endovascular Flow Diversion for Hemifacial Spasm Induced by a Vertebral Artery Aneurysm: First Experience.

BACKGROUND AND IMPORTANCE: Flow diversion for the treatment of aneurysm-induced hemifacial spasm (HFS) has not been previously described. CLINICAL PRESENTATION: The authors present the case of a 60-yr-old woman who presented with 1 yr of progressive left HFS secondary to a vertebral artery aneurysm compressing the root entry zone of cranial nerve VII. The patient's aneurysm was successfully treated with a flow diverting stent. CONCLUSION: In the immediate postoperative period, the patient had near complete resolution of her HFS symptoms. At her 6-mo follow-up the patient had no angiographic filling of the aneurysm and her HFS symptoms had completely resolved.

Clinical Risk Factors and Postoperative Complications Associated with Unplanned Hospital Readmissions After Cranial Neurosurgery.

BACKGROUND: Hospital readmission is a key surgical quality metric associated with financial penalties and greater healthcare costs. We examined the clinical risk factors and postoperative complications associated with 30-day unplanned hospital readmissions after cranial neurosurgery. METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program database from 2011 to 2016 for adult patients who had undergone a cranial neurosurgical procedure. Multivariable logistic regression with backward model selection was used to determine the predictors associated with 30-day unplanned hospital readmission. RESULTS: Of 40,802 cranial neurosurgical cases, 4147 (10.2%) required an unplanned readmission. Postoperative complications were greater in the readmission cohort (18.5% vs. 9.9%; P < 0.001). On adjusted analysis, the clinical factors predictive of unplanned readmission included hypertension, chronic obstructive pulmonary disease, diabetes, coagulopathy, chronic steroid use, and preoperative anemia, hyponatremia, and hypoalbuminemia (P ≤ 0.01 for all). Higher American Society of Anesthesiology class (III to V), operative time >216 minutes, and unplanned reoperation were also associated with an increased likelihood of readmission (P ≤ 0.001 for all). The postoperative complications predictive of unplanned readmissions were wound infection (odds ratio [OR], 4.90; P < 0.001), pulmonary embolus (OR, 3.94; P < 0.001), myocardial infarction or cardiac arrest (OR, 2.37; P < 0.001), sepsis (OR, 1.73; P < 0.001), deep venous thrombosis (OR, 1.50; P = 0.002), and urinary tract infection (OR, 1.45; P = 0.002). Female sex, transfer status, and postoperative pulmonary complications were protective of readmission (P < 0.05 for all). CONCLUSIONS: Unplanned hospital readmission after cranial neurosurgery is a common event. The identification of high-risk patients who undergo cranial procedures might allow hospitals to reduce unplanned readmissions and their associated healthcare costs.

Survival in unresectable sinonasal undifferentiated carcinoma treated with concurrent intra-arterial cisplatin and radiation.

We report the successful use of RADPLAT to treat a patient with an unresectable T4N0 sinonasal undifferentiated carcinoma. This patient received 4 cycles of weekly intra-arterial cisplatin together with thiosulfate infusion with concurrent radiation therapy. Radiation therapy was given in 28 daily fractions to 54 Gy using intensity-modulated radiation therapy followed by a hypofractionated stereotactic boost of 3 fractions to 13 Gy to a total dose of 67 Gy in 31 fractions to the nasal sinus and bilateral neck. Intra-arterial cisplatin was administered using a bilateral approach due to the midline site of this tumor. Within days of the first intra-arterial cisplatin, there was an obvious decrease in tumor size. She has been followed with magnetic resonance imaging and positron emission tomography, and remains disease-free 47 mo post-treatment. Centers with expertise in intra-arterial chemotherapy could consider the RADPLAT approach for patients with unresectable sinonasal undifferentiated carcinoma.

Comparative evaluation of noninvasive compression adjuncts for hemostasis in percutaneous arterial, venous, and arteriovenous dialysis access procedures.

PURPOSE: To assess the relative efficacy of three compression adjuncts -- D-Stat Dry (D-Stat), QR Powder (QR), and XS Powder (XS) -- for reducing time to hemostasis in patients who underwent diagnostic and interventional percutaneous procedures. MATERIALS AND METHODS: D-Stat, QR, or XS was applied in 176 percutaneous diagnostic arterial, therapeutic arterial, venous, and arteriovenous dialysis access (AVDA) procedures in 138 patients. The mean time to hemostasis and application-related complications were retrospectively assessed. RESULTS: Mean time to hemostasis was significantly reduced in all applications of QR (3.1 minutes +/- 1.1) and XS (3.7 minutes +/- 1.1) relative to D-Stat (6.2 minutes +/- 1.1, P < .001 vs both). For therapeutic arterial procedures, mean time to hemostasis for QR and XS was 3.6 minutes +/- 1.1 and 4.8 minutes +/- 1.1, respectively, and this was significantly less than that of D-Stat (10.0 minutes +/- 1.2; P < .001 vs QR, P < .01 vs XS). Mean times to hemostasis for QR and XS were also shorter than that with D-Stat in diagnostic arterial and AVDA procedures (P < .05). For venous procedures, mean time to hemostasis for QR (1.9 minutes +/- 1.2) was significantly shorter than that with both D-Stat (4.0 minutes +/- 1.2, P < .05) and XS (3.7 minutes +/- 1.2, P < .05). Minor immediate complications (hematoma <5 cm) occurred in 2.8% of applications. No access site infections were observed. CONCLUSIONS: All three agents effectively reduced time to hemostasis with minimal associated complications. QR was found to be more effective than D-Stat in all four procedure types.

Rapid clot removal for acute stroke therapy: technical case report.

OBJECTIVE: Endovascular therapy for acute ischemic stroke offers hope to those patients who do not meet the strict inclusion criteria for intravenous tissue plasminogen activator. Because no approach or device can be optimal for every patient, it is desirable to have options. This case is the first report on a novel retrieval device which proved to be very effective in our patient. CLINICAL PRESENTATION: A 69-year-old woman with an acute ischemic stroke was excluded from treatment with intravenous tissue plasminogen activator because of an elevated international normalized ratio. INTERVENTION: We successfully treated this patient endovascularly using a device newly approved by the Food and Drug Administration. We achieved rapid recanalization and an excellent clinical outcome. CONCLUSION: Using a new retrieval device, we were able to rapidly and successfully treat an acute ischemic stroke in a patient not eligible for intravenous thrombolysis. This may offer another alternative in endovascular acute stroke therapy.

An expedited code stroke protocol is feasible and safe.

BACKGROUND AND PURPOSE: Stroke recovery critically depends on timely reperfusion. In July 2003, we set a benchmark onset-to-treatment time of < or =2 hours and instituted an expedited code stroke protocol to accomplish this. We aim to show that the protocol is feasible and safe. METHODS: The expedited protocol includes: Benchmark onset-to-treatment within 2 hours; in-person triage of all code stroke patients; unmixed tissue plasminogen activator at the bedside during evaluation; no delays pending coagulation tests, chest x-ray, or stool guiac unless specifically indicated; and no delays pending formal CT interpretation or written consent. RESULTS: Between July 2003 and June 2005, we evaluated 781 patients and treated 103 of 781 (13.2%) with intravenous recombinant tissue plasminogen activator within 3 hours. Of these, we treated 49 of 103 (47.6%) within 2 hours of symptom onset, and 54 of 103 (52.4%) between 2 and 3 hours. The overall risk of symptomatic intracerebral hemorrhage was 4 of 103 (3.9%; 95% CI, 1.1%, 9.6%), and not significantly different from 6.4% (P=0.42). The hemorrhage risks in those treated within 2 hours of symptom onset and those treated between 2 and 3 hours were not significantly different from each other or from 6.4%. CONCLUSIONS: The expedited code stroke protocol is feasible and appears safe. Further study is warranted to confirm its safety and determine whether it results in better clinical outcomes.