Comparative Studies of Cerebral Reperfusion Injury in the Posterior and Anterior Circulations After Mechanical Thrombectomy

Cerebral reperfusion injury is the major complication of mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Contrast extravasation (CE) and intracranial hemorrhage (ICH) are the key radiographical features of cerebral reperfusion injury. The aim of this study was to investigate CE and ICH after MT in the anterior and posterior circulation, and their effect on functional outcome. This is a retrospective study of all consecutive patients who were treated with MT for AIS at University of California Irvine Medical Center between January 1, 2014, and December 31, 2017. Patient characteristics, clinical features, procedural variables, contrast extravasation, ICH, and outcomes after MT were analyzed. A total of 131 patients with anterior circulation (AC) stroke and 25 patients with posterior circulation (PC) stroke underwent MT during the study period. There was no statistically significant difference in admission NIHSS score, blood pressure, rate of receiving intravenous tPA, procedural variables, contrast extravasation, and symptomatic ICH between the 2 groups. Patients with PC stroke had a similar rate of favorable outcome (mRS 0–2) but significantly higher mortality (40.0% vs. 10.7%, p < 0.01) than patients with AC stroke. Multivariate regression analysis identified initial NIHSS score (OR 1.1, CI 1.0–1.2, p = 0.01), number of passes with stent retriever (OR 2.1, CI 1.3–3.6, p < 0.01), and PC stroke (OR 9.3, CI 2.5–35.1, p < 0.01) as independent risk factors for death. There was no significant difference in functional outcomes between patients with and without evidence of cerebral reperfusion injury after MT. We demonstrated that AC and PC stroke had similar rates of cerebral reperfusion injury and favorable outcome after MT. Cerebral reperfusion injury is not a significant independent risk factor for poor functional outcome.

Safety and efficacy of emergency transarterial embolization for mesenteric bleeding

Background Patients with spontaneous or traumatic active mesenteric bleeding cannot be treated endoscopically. Transarterial embolization can serve as a potential alternative to emergency surgery. Literature on transarterial embolization for mesenteric bleeding remains very scarce. The objective of this study was to evaluate the safety and efficacy of transarterial embolization for mesenteric bleeding. We reviewed all consecutive patients admitted for mesenteric bleeding to the interventional radiology department, in a tertiary center, between January 2010 and March 2021. Mesenteric bleeding was defined as mesenteric hematoma and contrast extravasation and/or pseudoaneurysm visible on pre-operative CT scan. We evaluated technical success, clinical success, and complications. Results Among the 17 patients admitted to the interventional department for mesenteric bleeding, 15 presented with active mesenteric bleeding requiring transarterial embolization with five patients with hemodynamic instability. Mean age was 67 ± 14 years, including 12 (70.6%) males. Technical success was achieved in 14/15 (93.3%) patients. One patient with technical failure was treated by percutaneous embolization with NBCA-Lipiodol mixture. Three patients (20%) had early rebleeding: two were treated by successful repeat embolization and one by surgery. One patient (6.7%) had early death within 30 days and two patients (13.3%) had late death after 30 days. Mean length of hospitalization was 12.8 ± 7 days. There were no transarterial embolization-related ischemic complications. Conclusion Transarterial embolization is a safe and effective technique for treating mesenteric bleeding even in patients with hemodynamic instability. Transarterial embolization doesn’t close the door to surgery and could be proposed as first intention in case of mesenteric bleeding.

Characterization of Subarachnoid Hyperdensities After Thrombectomy for Acute Stroke Using Dual-Energy CT

Background and Objectives:The presence of post-interventional subarachnoid hyperdensities (SA-HD) is a relatively common finding after mechanical thrombectomy (MT). We aimed to assess the incidence, characteristics, clinical relevance and predictors of SA-HD after MT as categorized through the use of post-interventional Dual Energy-CT (DE-CT).Methods:A single-center consecutive series of acute stroke patients treated with MT were retrospectively reviewed. Post-treatment SA-HD were defined as incident extra-axial hyperdensities in a follow-up DE-CT performed within a median of 8 hours after MT. SA-HD were further classified according to their content (isolated contrast extravasation versus blood extravasation) and extension [diffuse (hyperdensities in more than one extraparenchymal compartments) versus non-diffuse]. Adjusted logistic regression models assessed the association of SA-HD with pretreatment and procedural variables and with bad clinical outcome (shift towards worse categories in the ordinal Rankin Scale at 90 days).Results:SA-HD were observed in 120 (28%) of the 424 included patients (isolated contrast extravasation n=22, blood extravasation n=98). In this group, SA-HD were diffuse in 72 (60%) patients (isolated contrast extravasation n=7, blood extravasation n=65) and non-diffuse in 48 (40%) patients (isolated contrast extravasation n=15, blood extravasation n=33). Diffuse SA-HD were significantly associated with worse clinical outcome in adjusted models (cOR=2.3, 95%CI=1.36-4.00, p=0.002), unlike the specific SA-HD content alone. In contrast with the absence of SA-HD, only the diffuse pattern with blood extravasation was significantly associated with worse clinical outcome (cOR=2.4, 95%CI=1.36-4.15, p=0.002). Diffuse SA-HD patterns were predicted by M2 occlusions, more thrombectomy passes and concurrent parenchymal hematomas.Discussion:In our cohort of patients imaged within a median of 8 hours after MT, post-interventional SA-HD showed a diffuse pattern in 17% of thrombectomies and were associated with more arduous procedures. Diffuse SA-HD but not local collections of blood or contrast extravasations were associated with an increased risk of poor outcome and death. These findings reinforce the need for improvement in reperfusion strategies.Classification of Evidence:This study provides Class II evidence that in individuals with proximal carotid artery territory occlusions treated with mechanical thrombectomy, diffuse post-interventional subarachnoid hyperdensities on imaging 8 hours post-procedure are associated with worse clinical outcomes at 90 days.

A very rare complication of subacute pericarditis: a case report of spontaneous coronary artery rupture

Background Spontaneous coronary artery rupture (SCAR) is an extremely rare and highly lethal disease. Case Summary A 74-year-old man who had undergone respiratory surgery (robot-assisted thoracoscopic surgery) presented with exertional dyspnoea since post-operative day (POD) 6. Echocardiography and contrast-enhanced computed tomography showed diffuse pericardial effusion, and a 12-lead electrocardiogram showed widespread concave ST-segment elevation. The diagnosis of acute pericarditis was made based on the absence of significant elevation of cardiac enzymes and the presence of elevated C-reactive peptide levels. The patient was started on anti-inflammatory medication, including steroids; however, on POD 11, the patient developed a sudden cardiopulmonary arrest due to cardiac tamponade. Extracorporeal cardiopulmonary resuscitation was performed, and an emergency coronary angiography showed contrast extravasation from the left anterior descending artery to the epicardium. He was diagnosed with SCAR and underwent transcatheter arterial embolisation (TAE) and pericardial drainage. Discussion In this case, SCAR occurred during the course of acute pericarditis. We speculated that the cause of SCAR was more affected with pericarditis than injury by the respiratory surgery. The clinical course of acute pericarditis generally has a good prognosis, but the rare occurrence of fatal complications should be considered, suggesting the need for careful follow-up. In addition, TAE was a less invasive and feasible treatment for SCAR.

Fatal hemorrhagic complication after coil embolization of a petrosal arteriovenous shunt

Background Cerebello-pontine AVMs (CPAVMs) and petrous apex dural arteriovenous fistulae (DAVFs) are rare and sometimes difficult to distinguish. We report a fatal hemorrhagic complication after coil embolization of the petrosal vein draining a trigeminal AVM misdiagnosed as a DAVF. Case presentation A 73-year-old woman with a petrous apex arteriovenous shunt with dual dural and pial arterial supply presented with posterior fossa hemorrhage. The draining petrosal vein was catheterized and coiled via the superior petrosal sinus. Two episodes of contrast extravasation occurred during coiling, but the lesion was completely occluded at the end of the procedure. The patient developed a fatal posterior fossa hemorrhage in the recovery room. Microscopic pathology revealed numerous dilated vessels within the trigeminal nerve. Conclusion CPAVMs and DAVFs with pial drainage should be distinguished pre-operatively. Occlusion of a pial vein (as opposed to a sinus) in the treatment of an arteriovenous shunt carries hemorrhagic risk if a liquid embolic agent is not used to completely occlude all pathological vessels.

Gastric perforation leading to the diagnosis of classic Ehlers–Danlos syndrome: a case report

Background Ehlers–Danlos syndrome is a clinically and genetically heterogeneous group of heritable connective tissue disorders caused by a defect in collagen synthesis and structure. The vascular subtype (Ehlers–Danlos syndrome IV) is reported to be associated with a higher incidence of gastrointestinal perforations. The most reported site of perforation is the colon, followed by the small bowel. Perforation of the stomach is very rare, and there are no reported cases to date of classic types I and II. Case presentation We present the case of a 14-year-old Saudi girl who visited our emergency department with abdominal pain and vomiting. Initially, she was diagnosed with gastroenteritis and discharged once her condition stabilized. After 48 hours, she developed severe abdominal pain with recurrent vomiting and peritonitis evident on clinical examination. Initial abdominal x-ray failed to show any free air; however, enhanced computed tomography revealed free air and contrast extravasation in the proximal gut. During exploratory laparotomy, a large perforation was found on the anterior wall of the stomach due to the underlying ischemia. The posterior wall had ischemic mucosa with an intact healthy serosa. A free-hand partial gastrectomy was performed to resect all ischemic parts of the stomach. Detailed examinations and laboratory workup were carried out after the surgery to figure out the possible underlying cause. The clinical findings during the physical examination supported marfanoid features. Marfan’s syndrome and related disorders sequencing panel was requested, and Deoxyribonucleic acid (DNA) samples were sent. Given results were supporting the diagnosis of classical Ehlers–Danlos syndrome, the patient was labeled as a case of Ehlers–Danlos syndrome. During the postoperative period, she developed a wound infection that was managed successfully with vacuum-assisted closure dressing. She recovered well without gastrointestinal sequelae in the 4 years of follow-up. Conclusions Heritable systemic connective tissue diseases must be given serious consideration in young patients with unusual spontaneous perforation. Such patients might develop life-threatening conditions that require immediate intervention. Hence, correct and timely diagnosis is important to prepare for the anticipated complications.

Contrast extravasation from basilar artery without aneurysm formation on digital subtraction angiography in computed tomography angiogram-negative subarachnoid hemorrhage: A case report

Background: The causes of angiogram-negative subarachnoid hemorrhage (SAH) on initial angiography, which accounts for 10–30% of spontaneous SAH, are heterogeneous and still unclear. We report a case of nonaneurysmal SAH, in which initial computed tomographic angiography (CTA) showed no source of bleeding, but the subsequent digital subtraction angiography (DSA) revealed contrast extravasation from the basilar artery without aneurysms. Case Description: A 67-year-old woman with a medical history of hypertension presented as SAH of World Federation of Neurological Surgeons Grade II. CTA on admission did not show any cause of bleeding and DSA was subsequently performed to show contrast extravasation from a perforator of the middle third of the basilar artery without aneurysms during the subsequent DSA, resulting in profound deterioration SAH and neurological status. The patient was conservatively treated. Follow-up DSAs on days 2 and 16 showed no source of bleeding as well. Conclusion: Although the precise cause of bleeding in this case is uncertain, SAH might be caused by local dissection of the basilar artery perforator, and the bleeding site might heal spontaneously without forming of a pseudoaneurysm.

Risk factors of contrast extravasation and subsequent hemorrhagic transformation after thrombectomy

Objective The risk factors associated with iodine contrast extravasation immediately after endovascular thrombectomy (EVT) and subsequent hemorrhagic transformation within 24 hours remain unclear. Methods Mixed images, iodine overlay maps, and virtual non-contrast images were reconstructed from 106 consecutive acute ischemic stroke patients who underwent dual energy computed tomography immediately and 24 hours after EVT. Multivariate analyses of clinical and radiological data were performed to explore independent predictors of iodine contrast extravasation and hemorrhagic transformation. Results Sixty-eight (64.2%) patients exhibited pure iodine contrast extravasation after EVT; 30.9% developed hemorrhagic transformation within 24 hours after EVT. The number of stent retriever passes was independently associated with both iodine contrast extravasation (odds ratio 1.608; 95% confidence interval (CI) 1.047–2.469) and subsequent hemorrhagic transformation (odds ratio 1.477; 95% CI 1.003–2.175). Patients with more than two stent retriever passes were more likely to exhibit iodine contrast extravasation (sensitivity = 68.2%, specificity = 81.5%), while those with more than three stent retriever passes more often exhibited hemorrhage after iodine contrast extravasation (sensitivity = 64.6%, specificity = 87.2%). Conclusions The number of stent retriever passes was an independent predictor for both iodine contrast extravasation and subsequent hemorrhagic transformation.

The Intraoperative Use of a Portable Cone-Beam Computed Tomography System for the Diagnosis of Intraperitoneal Bladder Perforation

Background. Intraoperative imaging for endourologic procedures is generally limited to single-plane fluoroscopic X-ray. The O-arm™ is a mobile cone-bean CT scanner that may have applications in urologic surgeries. Case Presentation. We present a case of an 85-year-old male with radiation cystitis and recurrent gross hematuria who was identified to have a bladder perforation on cystoscopy during emergent clot evacuation. Single-view fluoroscopic evaluation was inconclusive as to whether an intraperitoneal bladder perforation occurred. A portable cone-beam CT scan was used to acquire a 3-D CT cystogram, which demonstrated intraperitoneal contrast extravasation, confirming the diagnosis of an intraperitoneal bladder perforation. Conclusion. We report the first use of a portable cone-beam CT scanner to perform an intraoperative CT cystogram to diagnose an intraperitoneal bladder perforation and guide surgical management.