Sameer A. Ansari

Treatment of carotid cavernous fistulas

Opinion statementThe treatment of a carotid cavernous fistula (CCF) depends on the severity of the clinical symptoms, its angiographic characteristics, and the risk it presents for intracranial hemorrhage. In most instances, endovascular treatment is preferred.High-flow direct CCFs usually are traumatic or are caused by rupture of a cavernous aneurysm into the sinus, but a small percentage can be spontaneous. They usually present with sudden development of a clinical triad: exophthalmos, bruit, and conjunctival chemosis. All direct CCFs should receive treatment, because they carry a high probability of intracranial hemorrhage or neurologic deterioration.Low-flow indirect or dural CCFs, either incidental or with minimal symptoms, are not associated with significant risk of intracranial hemorrhage. The accepted practice is to treat ocular symptoms conservatively with medical management or manual carotid compression. If the patient cannot tolerate the symptoms, or if signs of ocular morbidity occur, endovascular treatment is offered.The first treatment option should be endovascular embolization with a combination of detachable balloons, coils, stents, or liquid embolic agents. The procedure can be performed from either an arterial or venous approach. Use of these materials and techniques can yield a high cure rate with minimal complications.If the patient is not amenable to embolization or if the embolization fails, then surgery (surgical ligation of the internal carotid artery or packing of the cavernous sinus) should be offered.Stereotactic radiosurgery may be an elective treatment for low-flow CCFs, but it has no role in the treatment of high-flow CCFs.

Usefulness of percutaneously injected ethylene-vinyl alcohol copolymer in conjunction with standard endovascular embolization techniques for preoperative devascularization of hypervascular head and neck tumors: Technique, initial experience, and correlation with surgical observations

BACKGROUND AND PURPOSE: Few reports have described the embolization of head and neck lesions by using direct percutaneous techniques. We report our preliminary experience in the direct percutaneous embolization of hypervascular head and neck tumors by using Onyx in conjunction with standard endovascular embolization techniques. We describe the technical aspects of the procedure and its efficacy in reducing intraoperative blood loss. MATERIALS AND METHODS: We retrospectively studied 14 patients (3 females and 11 males; mean age, 33.4 years; range, 11–56 years) with 15 hypervascular tumors of the head and neck that underwent direct percutaneous embolization with Onyx in conjunction with particulate embolization. Nine paragangliomas and 6 JNAs underwent treatment. Documented blood loss was obtained from operative reports in these 15 patients with surgical resection performed 24–48 hours after the embolization. RESULTS: Intratumoral penetration with progressive blood flow stasis was achieved during each injection. A mean of 3.1 needles (20-gauge, 3.5-inch spinal needle) were placed percutaneously into the lesion (range, 1–6). The mean intraoperative blood loss was 780 mL (range, <50–2200 mL). Near total angiographic devascularization was achieved in 13 of 15 tumors. There were no local complications or neurologic deficits from the percutaneous access or embolization of these hypervascular tumors. CONCLUSIONS: In this study, the use of percutaneous injected Onyx in conjunction with standard endovascular embolization techniques in patients with hypervascular head and neck tumors seemed to enhance the ability to devascularize these tumors before operative removal.

Acute Life-Threatening Hemorrhage in Patients with Head and Neck Cancer Presenting with Carotid Blowout Syndrome: Follow-Up Results after Initial Hemostasis with Covered-Stent Placement

BACKGROUND AND PURPOSE: CSP in patients with HNC presenting with CBS can provide immediate hemostasis to prevent exsanguination. We evaluated the safety and efficacy of CSP to control acute life-threatening hemorrhage in patients with HNC presenting with CBS. MATERIALS AND METHODS: We retrospectively reviewed 10 patients (7 men, 3 women; mean age, 59 years) with HNC presenting with acute life-threatening hemorrhage from CBS that was treated with CSP. We studied patient demographics, presentations, procedures, initial and delayed complications, and technical and clinical outcomes on follow-up. RESULTS: All patients achieved immediate hemostasis following CSP. Periprocedural complications consisted of groin hematomas (n = 2), acute limb ischemia requiring thrombectomy, and an asymptomatic temporal lobe hemorrhage. Imaging and clinical follow-up were available for a mean of 17.7 months (range, 1–60 months). Two patients remained asymptomatic with a patent stent and no evidence of rebleeding at 17 and 21 months, respectively. Recurrent hemorrhages requiring retreatment were encountered in 3 patients secondary to stent infections (30%) at mean duration of 8 months. Neurologic morbidity resulted from stent thrombosis and stroke at 8 months in a single patient. Mortality was unrelated to CSP but was a result of palliative hospice care (n = 3) at a mean of 2 months or natural disease progression (n = 1) with documented patency of the stent at 6 months. CONCLUSIONS: Acute life-threatening hemorrhage from CBS related to advanced HNC can be safely and effectively treated with CSP. However, potential delayed ischemic or infectious complications are common in the exposed or infected neck.

Successful transarterial embolization of a barrow type D dural carotid-cavernous fistula with ethylene vinyl alcohol copolymer (Onyx)

Endovascular occlusion via the transvenous route is the favored treatment method for dural carotid-cavernous fistulas (CCFs). Ethylene vinyl alcohol copolymer (Onyx), recently approved for treatment of arteriovenous malformations, has advantages over conventional liquid embolic agents in its nonadhesive nature, which allows for longer injections with decreased risk of catheter retention. We report the use of Onyx in the successful transarterial embolization of a dural CCF fed by arterial branches of the internal and external carotid arteries (Barrow type D) after multiple failed attempts to access the cavernous sinus transvenously. Transarterial Onyx embolization could be a valuable option in transarterial treatment of CCFs when venous access is difficult.

Embolization of Vascular Tumors of the Head and Neck

Juvenile nasopharyngeal angiofibromas and paragangliomas are the most common hypervascular tumors of the head and neck that require embolization as an adjunct to surgery. A detailed understanding of the functional vascular anatomy of the external carotid artery is necessary for safe and effective endovascular therapy. Embolization, using a transarterial technique and particulate agents, a direct puncture technique and liquid embolic agents, or both techniques may allow for complete devascularization of hypervascular tumors of the head and neck. Effective embolization of these tumors results in a significant reduction of blood loss during surgery and allows for complete resection of the tumors. Use of meticulous technique and a thorough knowledge of functional anatomy of the head and neck vasculature are essential.

Safety of Intravenous Thrombolytic Use in Four Emergency Departments Without Acute Stroke Teams

OBJECTIVESnThe objective was to evaluate safety of intravenous (IV) tissue plasminogen activator (tPA) delivered without dedicated thrombolytic stroke teams.nnnMETHODSnThis was a retrospective, observational study of patients treated between 1996 and 2005 at four southeastern Michigan hospital emergency departments (EDs) with a prospectively defined comparison to the National Institute of Neurological Disorders and Stroke (NINDS) tPA stroke study cohort. Main outcome measures were mortality, intracerebral hemorrhage (ICH), systemic hemorrhage, neurologic recovery, and guideline violations.nnnRESULTSnA total of 273 consecutive stroke patients were treated by 95 emergency physicians (EPs) using guidelines and local neurology resources. One-year mortality was 27.8%. Unadjusted Cox model relative risk (RR) of mortality compared to the NINDS tPA treatment and placebo groups was 1.20 (95% confidence interval [CI] = 0.87 to 1.64) and 1.04 (95% CI = 0.76 to 1.41), respectively. The rate of significant ICH by computed tomography (CT) criteria was 6.6% (odds ratio [OR] = 1.03, 95% CI = 0.56 to 1.90 compared to the NINDS tPA treatment group). The proportions of symptomatic ICH by two other prespecified sets of clinical criteria were 4.8 and 7.0%. The rate of any ICH within 36 hours of treatment was 9.9% (RR = 0.94, 95% CI = 0.58 to 1.51 compared to the NINDS tPA group). The occurrence of major systemic hemorrhage (requiring transfusion) was 1.1%. Functional recovery by the modified Rankin Scale score (mRS = 0 to 2) at discharge occurred in 38% of patients with a premorbid disability mRS < 2. Guideline deviations occurred in the ED in 26% of patients and in 25% of patients following admission.nnnCONCLUSIONSnIn these EDs there was no evidence of increased risk with respect to mortality, ICH, systemic hemorrhage, or worsened functional outcome when tPA was administered without dedicated thrombolytic stroke teams. Additional effort is needed to improve guideline compliance.

Cervical Dissections: Diagnosis, Management, and Endovascular Treatment

Cervical arterial dissections and dissecting aneurysms are relatively rare pathologies, but can be associated with significant morbidity from ischemic complications. We review the challenges in diagnosing cervical arterial dissections, their unique clinical presentations and imaging characteristics. Although the majority of cervical dissections heal spontaneously with medical management, we discuss the specific indications for surgical or endovascular treatment to prevent thromboembolic complications. Furthermore, we provide a detailed technical review on endovascular stent reconstruction, the primary interventional option for symptomatic cervical dissections and dissecting aneurysms refractory to medical management.

Delayed Development of Brain Abscesses Following Stent-Graft Placement in a Head and Neck Cancer Patient Presenting with Carotid Blowout Syndrome

We describe the delayed development of intracranial abscesses following emergent treatment with a covered stent-graft for carotid blowout syndrome (CBS) in a patient with head and neck cancer. The patient presented with hemoptysis and frank arterial bleeding through the tracheostomy site. A self-expandable stent-graft was deployed across a small pseudoaneurysm arising from the right common carotid artery (RCCA) and resulted in immediate hemostasis. Three months later, the patient suffered a recurrent hemorrhage. CT of the neck demonstrated periluminal fluid around the caudal aspect of the stent-graft with intraluminal thrombus and a small pseudoaneurysm. Subsequently, the patient underwent a balloon test occlusion study and endovascular sacrifice of the RCCA and right internal carotid artery. MRI of the brain demonstrated at least four ring-enhancing lesions within the right cerebral hemisphere consistent with intracranial abscesses that resolved with broad-spectrum antibiotic coverage.

Role of perfusion imaging in differentiating multifocal vasospasm-related ischemia versus thromboembolic stroke in a setting of cocaine abuse.

Cerebrovascular complications related to cocaine abuse are reaching epidemic proportions. Contemporary treatments for acute stroke have made it essential to gather all possible diagnostic information before proceeding with intervention. We describe a cocaine abuser who presented with acute right sided neurological deficits and deteriorating mental status. An MRI demonstrated right sided acute and chronic infarcts in the border zones of the right anterior cerebral arteries (ACA) and middle cerebral arteries (MCAs). Subsequent CT angiography (CTA)/CT perfusion (CTP) identified multifocal cerebral vasospasm of the bilateral ACAs and MCAs, preserved cerebral blood volume (CBV) and decreased cerebral blood flow (CBF) in bilateral frontoparietal regions. Early diagnosis of multifocal vasospasm related ischemia directed appropriate therapy and excluded thrombolytic intervention. After 3 weeks, patients presenting symptoms gradually resolved. We report a unique case of cocaine induced multifocal vasospasm exhibiting late (>3 weeks) reversibility of focal neurological deficits. Furthermore, we illustrate the benefits of CTA/CTP imaging in the setting of cocaine abuse, differentiating multifocal vasospasm induced hypoperfusion/ischemia from focal thromboembolic ischemia/infarct and allowing for appropriate medical management in the crucial hyperacute setting.

Hemostasis and obliteration of mandibular arteriovenous malformation through direct hydroxyapatite cement injection into the molar cavity

A mandibular arteriovenous malformation (AVM) presented with massive molar socket bleeding and was emergently treated by tooth extraction and partial resection of the surrounding alveolar bone. To achieve hemostasis, the resultant cavity was filled with hydroxyapatite bone cement. Not only was hemostasis and alveolar reconstruction achieved, but follow-up angiography demonstrated venous outlet occlusion and retrograde AVM thrombosis requiring no further treatment.