Flow Diversion Therapy of Remnant and Recurrent Intracranial Aneurysms Treated Surgically.

AIM: To evaluate the safety and efficacy of flow diverter stents (FDSs) for treating remnant or recurrent intracranial aneurysms that were treated surgically. MATERIAL AND METHODS: The patients who were treated with FDSs due to remnant or recurrent intracranial aneurysms after microsurgery were included in the study. The patients' demographics, treatment histories, aneurysm features, complications associated with flow diversion, and neurological and angiographic follow-up findings were evaluated. RESULTS: Twenty patients (eight males) with 20 aneurysms were included in the study. Of 20 aneurysms, 18 (90%) were in the anterior, and two (10%) were in the posterior circulation. The initial treatment methods were clipping in 17 (85%) and wrapping in three (15%) aneurysms. The endovascular procedure was successful in all patients. In three patients (15%), periprocedural and postprocedural complications were encountered. No hemorrhagic complications were detected on cone-beam computed tomography. One patient with a basilary aneurysm died because of brain stem ischemia. The total morbimortality was 5%. The mean length of follow-up was 13.7 ± 7.3 months in 18 patients. The first angiographic follow-up (3-6 months) revealed the complete occlusion in 7 of 11 aneurysms (63.6%). By contrast, 16 aneurysms (94.1%) were occluded at the last angiographic follow-up, one aneurysm (5.9%) was still filling. CONCLUSION: An FDS seems effective, safe, and extremely attractive in treating remnant and recurrent intracranial aneurysms treated surgically.

Endovascular treatment modalities for basilar artery fenestration aneurysms: experience of two centers and literature review

Background/aim: The aim of this study is to present our experience on various endovascular treatment modalities of basilar fenestration aneurysms and reviewing our findings together with literature data. Materials and methods: A total of 26 basilar artery fenestration (BAF) aneurysms in 24 patients were endovascularly treated in two different neurointerventional radiology clinics. All patients had been evaluated with computed tomography (CT), CT angiography, and digital subtraction angiography before the procedure. Results: Aneurysms of all patients were successfully occluded (technical success rate 100%). Procedure-related complications were seen in two patients. Our comprehensive literature research revealed that studies related with the topic are composed mostly of case reports. In the literature, a total of 113 BAF aneurysms of 101 patients had been treated endovascularly in 46 studies between 1993 and 2019. Success rate of the treatment was reported as 97%, clinical success rate as 91%, and complication rate as 8.8%, while these rates are 100%, 92%, and 7.6% in our study, respectively. Conclusion: Although the number of cases is low in our study, to our knowledge, it is the widest series in the literature until today. Our results demonstrate that BAF aneurysms can be treated successfully and safely with different endovascular techniques, with more stent use in recent years.

Flow-diverting stent and delayed intracranial bleeding: the case for discussing acquired von Willebrand disease.

A unique feature of the flow-diverting stent (FDS) has rendered it useful in the endovascular treatment of selected intracranial aneurysms for the last decade. Delayed aneurysmal rupture and intracranial parenchymal bleeding are two leading hemorrhagic complications after FDS. It has recently been shown for the first time that there is a relationship between FDS and reduced level of vWF activity in patients undergoing endovascular cerebral aneurysm treatment. Here, the current literature is reviewed in the context of this novel finding to propose an illustrative scenario that conceptually links implantation of FDS to delayed intracranial bleeding, through the mechanism of shear-induced activation of vWF. In this scenario, after FDS implantation, sustained release of activated vWF in association with platelets plays a pivotal role in the mechanisms of delayed intracranial hemorrhages.

A rare cause of ischemic stroke in childhood: spontaneous long segment intracranial dissection.

Craniocervical arterial dissection is an important cause of arterial ischemic stroke in children. Recognition of dissections is of particular importance both in determining the risk of recurrence and in bringing about different treatment alternatives. We report a 10-year-old girl who presented with acute ischemic stroke due to spontaneous long segment dissection involving the parasellar internal carotid artery up to the distal M1 portion of the middle cerebral artery. Three-dimensional digital subtraction angiography with flat panel detector revealed the presence of major vessels originating from both true and false lumens and had a critical role in the treatment decision of the case.

Aggregometry Response to Half-dose Prasugrel in Flow-diverting Stent Implantation.

PURPOSE: The aim of this study was to determine whether half-dose loading (30 mg) of prasugrel is sufficient to achieve adequate platelet inhibition, and whether such a loading dose of prasugrel together with aspirin followed by a 10 mg/day prasugrel maintenance, could serve as a first-line antiplatelet strategy for patients undergoing flow-diverting stent (FDS) implantation. METHODS: Data from a group of consecutive patients treated for intracranial aneurysm with FDS were retrospectively collected. Platelet P2Y12 receptor responsiveness was assessed by a rapid platelet function test just prior to the procedure. All ischemic and hemorrhagic complications as well as morbidity and mortality rates were documented. RESULTS: A total of 138 patients with 153 aneurysms (32 were symptomatic and 121 were incidental) underwent FDS treatment in a total of 147 loading sessions. Adequate platelet inhibition was obtained in 136/138 (98.5%) patients and 145/147 (98.6%) loading sessions. Overall, there was one case of (hemorrhagic) mortality (0.7%), one of (ischemic) morbidity (0.7%), one of symptomatic (hemorrhagic) clinical complications without permanent deficits (0.7%), and six transient ischemic attacks (4.1%). The 6­month control angiography, available for all patients, revealed a 95.4% aneurysm occlusion rate. CONCLUSION: Half-dose (30 mg) prasugrel loading results in effective platelet P2Y12 receptor inhibition in more than 98% of patients. Dual antiaggregant loading with half dose prasugrel followed by prasugrel maintenance as a first-line therapy appears to be feasible in patients treated with FDS implantation for intracranial aneurysm.

Dual-Lumen Balloon Catheter Technique for Onyx Embolization of Spinal Dural Arteriovenous Fistula.

Spinal dural arteriovenous fistula (SDAVF) is the most common type of spinal vascular malformation. The main purpose of endovascular treatment is to occlude the fistula site and the proximal part of the draining vein. However, this is not always possible because of the difficulty of selective catheterization in patients with tortuous feeding arteries, as well as the risk of reflux of the liquid embolic agent. Herein, we present three cases in which a dual-lumen balloon catheter together with a liquid embolic agent was used to occlude the SDAVF. Complete and persistent occlusion was confirmed by magnetic resonance images taken at 6 months after the treatment. Using the dual-lumen balloon catheter technique in cases of long and tortuous feeder arteries supplying the SDAVF can result in safe and successful embolization.

Eagle Syndrome Presenting with Neurological Symptoms.

AIM: Eagle syndrome is a rare entity that causes recurrent throat pain, neck pain, dysphagia, or facial pain due to an elongated styloid process or calcified stylohyoid ligament. Clinical findings related to lower cranial nerve compression have also been reported. In some cases, it is reported that carotid artery compression or dissection can be seen due to elongated styloid process and this is called carotid artery syndrome. Carotid artery compression causes flow reduction and carotidynia or neurological symptoms can be seen. Dural sinuses and the jugular vein can be compressed. Eagle syndrome with neurological symptoms has been rarely reported. MATERIAL AND METHODS: The data of 5 patients (aged between 22 and 68 years), who presented to the hospital with various neurological symptoms, were retrospectively reviewed. Each patient underwent computed tomography (CT) that revealed a long styloid process. RESULTS: An elongated styloid process caused neurological symptoms. Two patients had venous compression by the styloid process and the other patients had transient ischemic attacks due to internal carotid artery compression by the styloid process. Only one patient underwent surgical removal. All patients" outcomes were good after treatment and no symptoms remained. CONCLUSION: Eagle syndrome may be presented with neurological symptoms. It should be kept in mind in the differential diagnosis of patients who have neurological symptoms without any objective etiological factors. To the best of our knowledge, Eagle syndrome with arterial and venous compression due to elongated styloid process has not been previously presented in the literature.

Endovascular Management of Iatrogenic Vascular Injury in the Craniocervical Region.

AIM: To evaluate iatrogenic vascular injuries in the craniocervical region and their endovascular management. MATERIAL AND METHODS: Twenty-one patients (9 women, 12 men) with a mean age of 53.6 years (range 16-87 years), who underwent endovascular embolization for iatrogenic vascular injury in the craniocervical region between December 2000 and October 2015, were included in this retrospective study. Types of iatrogenic injuries, etiologies that caused these injuries and details of endovascular managements were reported. RESULTS: The etiologies of the vascular injuries were as follows: transsphenoidal surgery (n=9), skull-base surgery (n=2), cholesteatoma surgery (n=1), tracheostomy (n=2), central venous catheterization (n=2), oropharyngeal tumor operation (n=1), endovascular treatment of internal carotid artery (ICA) stenosis (n=1), suprasellar epidermoid tumor operation (n=1), sphenoid sinus tumor surgery (n=1), and speech prosthesis device placement (n=1). The types of vascular injuries diagnosed at the time of angiography were; 2 occlusions, 2 stenoses, 2 dissections, 1 carotid cavernous fistula, 8 artery rupture with extravasation, and 9 pseudoaneurysms. Endovascular management of these vascular injuries were; parent artery occlusion (PAO) (n=15), aneurysm occlusion (n=3), covered stent (n=1) and conservative management (n=2). All patients except two were successfully treated. No patient had bleeding within a 30-day period after angiography. Long-term follow-up was available in all patients without occurrence of re-bleeding. One patient died due to complications related to primary vascular injury. CONCLUSION: Although iatrogenic vascular injuries are rare, early diagnosis and management may be lifesaving. Endovascular techniques are reliable and safe in most of the patients.

Iatrogenic Vascular Injuries Due to Spinal Surgeries: Endovascular Perspective.

AIM: Iatrogenic vascular injuries due to spinal surgeries are rare but serious complications. Surgical management of these injuries is challenging with high morbidity rates. In this study we aim to present the results of endovascular management of iatrogenic vascular injuries due to spinal surgeries. MATERIAL AND METHODS: We retrospectively reviewed 11 patients (5 male, 6 female) who had vascular injuries due to cervical and lumbar spinal surgeries. Clinical findings were bleeding (n=5), leg edema (n=6) and right heart failure with severe dyspnea (n=1). The age range of the patients were between 42-67 (mean: 57.1). Six patients were reviewed with imaging before the procedures and the rest of the patients (n=5) were directly referred to the angiography unit for diagnosis and possible endovascular treatment. RESULTS: The types of surgeries were; cervical surgery (n=5) and lumbar disc operation (n=6). The type of vascular injuries were; vertebral artery stenosis (n=1), vertebral artery pseudoaneurysm (n=3), vertebral artery occlusion (n=1) and iliac arteriovenous fistula (n=6). The type of endovascular treatments were; parent artery occlusion (PAO) (n=2), covered stent graft implantation (n=6) and intrasaccular coil embolization of pseudoaneurysm (n=1). The remaining 2 patients were managed conservatively. No major complications or mortality occured during endovascular interventions. No bleeding or ischemia occured in the follow-up period. CONCLUSION: Iatrogenic vascular injuries due to spinal surgeries are rare but serious complications. Endovascular interventions are safe and effective in the diagnosis and treatment of such vascular injuries.

A Case of Pseudoaneurysm of the Internal Carotid Artery Following Endoscopic Endonasal Pituitary Surgery: Endovascular Treatment with Flow-Diverting Stent Implantation.

Internal carotid artery (ICA) pseudoaneurysm is a rare complication of endoscopic endonasal surgery occurring in 0.4-1.1% of cases. Pseudoaneurysms can subsequently result in other complications, such as subarachnoid hemorrhage, epistaxis, and caroticocavernous fistula with resultant death or permanent neurologic deficit. In this case, we illustrate endovascular treatment with a flow-diverting stent for an ICA pseudoaneurysm after endoscopic endonasal surgery for a pituitary adenoma in a 56-year-old male. Surgery was complicated by excessive intraoperative bleeding and emergent CT angiography confirmed an iatrogenic pseudoaneurysm on the anteromedial surface of the ICA. The pseudoaneurysm was treated endovascularly with flow-diverting stent implantation only. Follow-up CT angiography after three months demonstrated occlusion of the pseudoaneurysm.

Ischemia-Modified Albumin as a Marker of Acute Coronary Syndrome: The Case for Revising the Concept of "N-Terminal Modification" to "Fatty Acid Occupation" of Albumin.

Ischemia-modified albumin (IMA) is assumed "N-terminal modified" albumin which is generated immediately following myocardial ischemia. The diagnosis of IMA is based on reduced cobalt binding affinity to albumin which is attributed mainly to incapability of cobalt to bind at albumin's modified N-terminus. Although the albumin cobalt binding test was accepted as a potentially powerful marker for discriminating acute coronary syndrome from nonischemic chest pain, its usefulness has been brought into question in recent years. Patients with acutely ischemic myocardium exhibit a rapid increase in serum levels of fatty acids (FAs). Almost all released FAs are strongly bound to albumin which create conformational changes in the protein with resultant reduced cobalt binding affinity. There is a clear metabolic and temporal relationship between IMA measured via albumin cobalt binding testing and serum levels of FAs. In line with what has been suggested recently in the literature, we conclude that a shift from the concept of "N-terminal modified" to "FA-occupied" albumin is required, as this better describes IMA in patients with acute coronary syndrome. We also offer "oxidation modified albumin, OMA," which is conceptually different from the "FA-occupied" IMA, to describe modification of albumin in chronic disease associated with increased oxidative stress.

Endovascular treatment of intracranial infectious aneurysms.

INTRODUCTION: Intracranial infectious aneurysm (IIA) accounts for less than 5% of all intracranial aneurysms. The aim of this study was to evaluate the role of endovascular treatment for IIA. METHODS: During a 14-year period, 15 patients (age range, 2-68 years; mean, 42.8 years) with 17 aneurysms were diagnosed with IIA and treated via an endovascular route at our institution. The IIA diagnosis was based on clinical and laboratory findings of infection, echocardiography results, and digital subtraction angiography that were collected retrospectively. All patients were clinically and radiologically followed. The modified Rankin scale was used to evaluate clinical outcome. RESULTS: Among 15 patients, 12 presented with ruptured aneurysms (7 intraparenchymal hematoma, 4 subarachnoid hemorrhage, 1 subdural hematoma), 2 with cerebral infarcts, and 1 with pansinusitis and epidural abscess. All but one aneurysm were distally located in intracranial circulation, 14 were in anterior, and the remaining 3 were in posterior circulation. The final diagnosis was based on aneurysm morphology, location, and clinical laboratory findings. Endovascular treatment was scheduled initially for all IIAs; 13 of 17 IIAs underwent endovascular parent vessel occlusion, 3 underwent spontaneous parent vessel occlusion while waiting for intervention, and the remaining patient was treated by intrasaccular coil occlusion. There were no instances of perioperative neurological complications. Late clinical and radiological outcomes included absence of endovascular treatment related to mortality and aneurysm recurrence. CONCLUSION: Endovascular treatment may be performed safely at the time of diagnosis for at least symptomatic IIAs under the protective effect of antibiotic treatment.

Imaging findings and endovascular management of iatrogenic hepatic arterial injuries.

Iatrogenic hepatic arterial injuries (IHAIs) include pseudoaneurysm, extravasation, arteriovenous fistula, arteriobiliary fistula, and dissection. IHAIs are usually demonstrated following percutaneous transhepatic biliary drainage, percutaneous liver biopsy, liver surgery, chemoembolization, radioembolization, and endoscopic retrograde cholangiopancreatography. The latency period between the intervention and diagnosis varies. The most common symptom is hemorrhage, and the most common lesion is pseudoaneurysm. Computed tomography angiography (CTA) is mostly performed prior to angiography, and IHAIs are demonstrated on CTA in most of the patients. Patients with IHAI are mostly treated by coils, but some patients may be treated by liquid embolic materials or stent-grafts. CTA can also be used in the follow-up period. Endovascular treatment is a safe and minimally invasive treatment option with high success rates.

Assessment of the Circle of Willis with Cranial Tomography Angiography.

BACKGROUND: The circle of Willis is a major collateral pathway important in ischemic conditions. The aim of our study was to assess the structural characteristics of the circle of Willis within the Turkish adult population, along with variations and arteries involved in the measurement of diameters and lengths on cranial computed tomography angiography (CTA). MATERIAL AND METHODS: One hundred adult patients who underwent CTA images were evaluated retrospectively. RESULTS: Results of the study revealed 82% adult, 17% fetal, and 1% transitional configurations. A complete polygonal structure was observed in 28% of cases. Variations of the circle of Willis were more common in the posterior portion. Hypoplasia was found to be the most common variation and was observed as a maximum in the posterior communicating artery (AComP). CONCLUSIONS: The patency and size of arteries in the circle of Willis are important in occlusive cerebrovascular diseases and cerebrovascular surgery. Although CTA is an easily accessible non-invasive clinical method for demonstrating the vascular structure, CTA should be evaluated taking into account image resolution quality and difficulties in the identification of small vessels.

Endovascular management of iatrogenic renal arterial lesions and clinical outcomes.

PURPOSE: We aimed to evaluate iatrogenic renal arterial lesions, including pseudoaneurysm, arteriovenous fistula, and arteriocaliceal fistula, their management by endovascular embolization, and the clinical results. METHODS: Fifty-five patients (forty males, fifteen females) with a median age of 40 years (range, 8-85 years), who underwent endovascular embolization of iatrogenic renal arterial lesions between March 2003 and December 2013 were included in this retrospective study. Types of iatrogenic lesions and details of embolization procedures were reported. Estimated glomerular filtration rate (eGFR), renal function tests, hemoglobin, and hematocrit levels before and after embolization were recorded and compared. RESULTS: Median follow-up was 24 months. We identified 53 pseudoaneurysms, 30 arteriovenous fistulas, and 11 arteriocaliceal fistulas in 55 patients, after percutaneous nephrolithotomy (n=26), renal biopsy (n=21), nephrostomy (n=3), renal surgery (n=3), and extracorporeal shock wave lithotripsy (n=2). Median number of pseudoaneurysms was 1 (range, 1-4) with a median size of 7 mm (range, 1.5-35 mm). Fifty-one patients underwent coil embolization. Median number of coils was 5 (range, 2-21) and median renal parenchymal loss was 5% (range, 1%-50%). There were no significant differences between pre- and postoperative eGFR and serum parameters. CONCLUSION: Iatrogenic renal arterial lesion can be a life threatening condition. Superselective coil embolization is a safe, minimally invasive treatment option with minimal renal parenchymal loss and without significant change in renal function.

The incidence of contrast medium-induced nephropathy following endovascular aortic aneurysm repair: assessment of risk factors.

PURPOSE: The aim of the study was to investigate the incidence of contrast medium-induced nephropathy (CIN) and risk factors for CIN following endovascular abdominal aortic aneurysm repair or thoracic endovascular aortic aneurysm repair. MATERIALS AND METHODS: After exclusion criteria, 139 (121 males, 18 females) patients aged 20-86 (median 65.5) years who underwent endovascular aortic aneurysm repair between January 2002 and September 2013 were included in this retrospective study. CIN, with ≥25% increase in serum creatinine levels within 3 days after contrast medium administration, was compared to the patients' demographics, risk factors, type and complexity of the endovascular operation, parameters regarding to the contrast medium, preoperative estimated glomerular filtration rate (eGFR), and preoperative and early postoperative serum parameters. Statistical analyses were performed with Kolmogorov-Smirnov, χ (2) and Student's t tests. RESULTS: CIN, detected in 39 of 139 patients (28%), was correlated with preoperative eGFR <60 ml/min/1.73 m(2) (P = 0.04) and high preoperative and postoperative serum urea and creatinine levels. Postoperative serum urea levels (P < 0.001) were significant in multivariate analysis. CONCLUSION: In patients undergoing endovascular aortic aneurysm repair, CIN was correlated with preoperative and postoperative renal impairment, while it was not correlated with the contrast medium dose.

Tailoring platelet inhibition according to multiple electrode aggregometry decreases the rate of thrombotic complications after intracranial flow-diverting stent implantation.

BACKGROUND AND PURPOSE: Pretreatment with dual antiaggregant drugs is accepted as a standard step in intracranial stent implantation. The aim of this study was to determine whether tailored antiaggregant medication based on platelet reactivity testing with multiple electrode aggregometry (Multiplate) yields superior outcomes after intracranial flow-diverting stent (FDS) implantation compared with standard clopidogrel treatment. METHODS: We retrospectively analyzed the following data from 100 consecutive patients: endovascular procedure characteristics, antiaggregant medications, procedural variables, and perioperative complications after FDS implantation for intracranial aneurysm. Patients were divided into two groups: uniform treatment with clopidogrel (untailored, early phase) and tailored treatment based on the results of aggregometry (late phase). Statistical comparisons included the Fisher exact test to compare categorical variables between the standard and aggregometry groups and the Mann-Whitney U test to compare ADP test values within the aggregometry group between groups receiving tailored or untailored treatment. RESULTS: In the aggregometry group (68 patients, 71 procedures) there were 17 (25%) clopidogrel-resistant patients, according to a cut-off value of 468 area under the aggregation curve; 12 underwent FDS implantation under tailored antiaggregant medication. In the standard treatment group (32 patients, 33 procedures) there were 3 (9.1%) spontaneous thrombotic events and 1 (3.3%) technical hemorrhagic complication. In the aggregometry group there were 2 (2.8%) spontaneous hemorrhagic events and 1 (1.4%) technical ischemic complication. In the aggregometry group, thrombotic complications and morbidity were lower than in the standard (no test) group (p<0.03). CONCLUSIONS: Tailoring platelet reactivity according to multiple electrode aggregometry decreases the rate of thrombotic complications after intracranial FDS implantation.